i

ii

UNIVERSITY OF JORDAN

FACULTY OF ENGINEERING AND TECHNOLOGY

DEPT.OF CHEMICAL ENGINEERING

PRODUCTION OF N-OCTANE

Done by:

Name ID Number
Fadi Droubi 0180782
Farah NoorAldeen Abu Gharbieh 0190719
Haneen Mohammad Alqatateshah 0194253
Rana Bassam Abu Al Soud 0196932
Tuqa Zeyad Ahmad 0198309
iii

EXECUTIVE SUMMARY: -
This project's primary goal was to produce (54,431) tons of n-octane annually. N-octane is a
hydrocarbon molecule made up of a chain of eight carbon atoms (C) joined by single bonds and
eighteen hydrogen atoms (H) that fill up all available valence bonds. The numerous applications
and domains in which n-octane is employed provide a rationale for choosing it over other
chemicals such as Fuel Component, Solvent (Laboratory Solvent, Industrial Solvents), and
Chemical Intermediate. The synthesis process for manufacturing n-octane from ethylene and iso-
butane is commonly used zeolite as a catalyst. The flow diagrams HYSSES simulation. Three main
equipment make up this process: the reactor, the phase separator, and the distillation columns.
Process variables such as flow rates, temperature, and pressure of each stream were determined by
applying material and energy balances.

This report contained a thorough material and energy balance as well as a complete design of the
principal pieces of equipment, including the heat exchangers, reactor, tower, flash drum, and
pump, Process control is important to ensure that process variability is controlled within
specifically defined boundaries, and derived from current product and process understanding, to
guarantee quality of the product, the section on safety and environmental problems looked at and
analyzed the material safety data sheet, the NEPA hazard rating diamond, the risks and material
operability, and the safety of the equipment. The site location is chosen based on various aspects
that impact the plant project's profitability, the N-octane production plant will be in Saudi Arabia
specifically in Yanbu.

Through studying the economic analysis of our plant and assuming that the life of the plant is valid
for 10 years we found using the CAPCOST program that the Payback period is three years and six
months, after that period the process will start earning money until the 10 years, Discounted Cash
Flow Rate of Return (9.82%).
iv

Acknowledgement

Dear Chemical Engineering Department Faculty,

As our academic journey concludes, we extend heartfelt gratitude for your invaluable guidance
during our senior project.

Your commitment to excellence and mentorship has been instrumental in our growth, illuminating
paths of inquiry and innovation. Your unwavering support has bolstered our confidence and
propelled us toward success.

Thank you for imparting not only knowledge but also values of integrity and perseverance. Your
influence will resonate in our professional pursuits and character development.

We would also like to extend our deepest appreciation to our parents for their unwavering
support and encouragement. Their belief in us has been a source of strength throughout this
journey.

Dr.Ali Al-Matar, your impact on our lives is immeasurable, and for that, we are profoundly
grateful. Thank you for being a guiding light, a source of wisdom, and a beacon of encouragement
throughout our senior project.

Lastly, we acknowledge the resilience and spirit of the people of Gaza. Their perseverance in the
face of adversity has been a source of inspiration for us, reminding us of the importance of
determination and hope.

With deepest appreciation and admiration,

Fadi Droubi

Farah NoorAldeen Abu Gharbieh

Haneen Mohammad Alqatateshah

Rana Bassam Abu Al Soud

Tuqa Zeyad Ahmad

v

NOMENCLATURE

Symbol Abbreviation Unit

A Area m2
Ac Total column cross sectional area m2
Ad Downcomer area m2
Ah Area of the hole m2
B Bottom flow rate from distillation Kmol/h
BFD Block flow diagram -
CP Heat capacity $
CGR Grassroots cost $
CTM Total module cost $
CBM Total bare module cost $
CP Purchased equipment cost $
COM Cost of manufacturing $
Cost of manufacturing without
COMD $
depreciation
CRM Cost of raw material $/kg
COL Cost of operating labor $
CWT Cost of waste treatment $
CUT Cost of utility $
D Diameter m
Dd Bundle diameter mm
Di Tube inside diameter mm
Do Tube outside diameter m
Ds Diameter of shell m
EAOC Equivalent annualized operating cost $/yr
EP Potential energy kw
EK Kinetic energy kw
F Feed molar flowrate Kmol/h
vi

FC Flow controller -
FCI Fixed Capital Investment -
𝑯 Enthalpy kJ/kmol
H Height m
HAZOP Hazard and Operability Analysis -
K Ratio of equilibrium gas constant -
L Length m
L Liquid mass flowrate Kg/s
LC Level controller -
LT Level transmitter -
M Number of mole mol
m mass kg
MW Molecular wight Kg/kmol
Nact Actual number of trays -
Nmin Minimum number of trays -
NOL Number of operators per shift Operators/shift
Nopt Optimum number of trays -
Nt Number of tubes -
P Pressure bar
PC Pressure controller -
PFD Process Flow Diagram -
Pt Tube pitch -
Q Volumetric flow rate m3/h
QC Condense heat duty kw
QR Reboiler heat duty kw
R Universal Gas Constant Jol/mol.k
R Revenue -
Rmin Minimum reflux ratio -
Rop The optimum reflux ratio -
O
T Temperature C or K
vii

TS Tray spacing mm
u Velocity m/s
U The overall heat transfer coefficient W/m2 /C
Uf Flooding velocity based on net active area m/s
Uh Minimum vapor velocity through the holes m/s
V Volume m3
W Weight Catalyst kg
X Conversion of Reactor %
XD Distillate mass fraction -
XF Feed mass fraction -
ZI Feed Mole fraction of component i -

GREEK SYMBOLS

Symbol Abbreviation Unit

𝝆 Density Kg/m3
µ Viscosity Kg/m.s
𝜺 Efficiency -
𝛕 Residence time min
𝛏̇ Extent of reaction Kmol/h
𝛔 Surface tension dyne/cm
𝝅 Pi -
𝜶 Relative volatility -
viii

Table of Contents:
1 CHAPTER 1: INTRODUCTION .......................................................................................................1
1.1 Background of n-Octane .............................................................................................................. 1
1.2 Physical and chemical properties of n-Octane ............................................................................. 2
1.3 Historical background of n-Octane .............................................................................................. 3
1.4 Uses and Application of n-Octane ............................................................................................... 4
1.5 Sources ......................................................................................................................................... 5
1.6 Environment impact of n-Octane ................................................................................................. 6
1.7 Raw materials ............................................................................................................................... 8
1.7.1 Iso-butane ................................................................................................................................. 8
1.7.2 Ethylene ................................................................................................................................... 9
1.8 Market study of n-Octane:.......................................................................................................... 11
2 CHAPTER 2: PROCESS SELECTION AND DESCRIPTION..................................................................15
2.1 Production of Octane from Ethylene and Iso-butane (alkylation): ............................................ 15
2.2 High-Octane Gasoline Production from Catalytic Naphtha Reforming: ................................... 16
2.3 The Fischer-Tropsch: ................................................................................................................. 17
2.4 Production of n-octane from biomass ........................................................................................ 18
2.5 Conclusion .................................................................................................................................. 18
2.6 PROCESS DESCRIPTION........................................................................................................ 18
2.7 Flow diagrams. ........................................................................................................................... 20
2.7.1 Input-Output diagram.............................................................................................................20
2.7.2 Block flow diagram (BFD) ....................................................................................................21
2.7.3 Process flow diagram (PFD) ..................................................................................................22
2.7.4 Process flow tables ................................................................................................................23
3 CHAPTER 3: MATERIALS BALANCE ............................................................................................. 25
3.1 Mixer (MIX-101) material balance ............................................................................................ 26
3.2 Plug flow reactor (R-101) material balance ............................................................................... 28
3.3 Flash Drum (V -101) material balance ....................................................................................... 30
3.4 Distillation Column (T -101) material balance .......................................................................... 33
3.5 Result for all Stream Flowrates: ................................................................................................. 35
3.5.1 Hand Calculation ...................................................................................................................35
3.5.2 HYSYS Calculation ...............................................................................................................36
3.5.3 Error between Scaled Hand Calculation and HYSYS Calculation ........................................37
ix

4 Chapter 4:Process Energy Balance ............................................................................................. 39

4.1 Process Energy Balance ............................................................................................................. 39
4.2 Plug flow Reactor (R-101) Energy Balance ............................................................................... 40
4.3 Distillation Column (T-101) energy balance ............................................................................. 43
4.4 Compressor (C-101) energy balance .......................................................................................... 45
4.5 Compressor (C-102) energy balance .......................................................................................... 46
4.6 Pump (P-101) energy balance .................................................................................................... 47
4.7 Heater (E-101) energy balance ................................................................................................... 48
4.8 Heater (E-102) energy balance ................................................................................................... 49
4.9 Heater ( E-105) energy balance .................................................................................................. 50
4.10 Heater (E-106) energy balance ................................................................................................... 52
4.11 Cooler (E-103) energy balance: ................................................................................................. 53
4.12 Cooler (E-104) energy balance: ................................................................................................. 54
4.13 Result of Energy Balance: .......................................................................................................... 56
5 CHAPTER 5: EQUIPMENT DESIGN .............................................................................................. 57
5.1 DESIGN OF REACTOR(R-101): .............................................................................................. 57
5.2 DESIGN OF DISTILLATION (T-101): .................................................................................... 64
5.3 Pumps and Compressors Design: ............................................................................................... 76
5.4 Design of flash drum: ................................................................................................................. 78
5.5 Design of thermosyphon reboiler:.............................................................................................. 81
5.6 Design of Heat Exchanger: ........................................................................................................ 85
5.6.1 Shell and tube heat-exchanger design:...................................................................................85
5.6.2 Double pipe design procedure: ..............................................................................................96
5.6.3 Summary table for HE design:.............................................................................................105
6 CHAPTER 6: ECONOMIC ANALYSIS AND COST ESTIMATION.................................................................... 106
6.1 FIXED CAPITAL INVESTMENT COST: ............................................................................. 106
6.2 GRASS ROOTS AND TOTAL MODULE COST: ................................................................. 109
6.3 COST OF MANUFACTURING: ............................................................................................ 110
6.3.1 FIXED CAPITAL INVESTMENT (FCI): ............................................................................111
6.3.2 Cost of Operating Labor (Col): ............................................................................................111
6.3.3 COST OF UTILITY (CUT):..................................................................................................113
6.3.4 COST OF MATERIALS: ....................................................................................................114
6.4 EQUIVALENT ANNUALIZED OPERATING COST (EAOC): ........................................... 115
6.5 REVENUE ESTIMATE .......................................................................................................... 116
x

6.6 PROFITABILITY ANALYSIS ............................................................................................... 116

6.6.1 CASH FLOW DIAGRAMS ................................................................................................116
7 CHAPTER 7: PROCESS CONTROL ..................................................................................................... 119
7.1 Compressor Control Loop: ....................................................................................................... 119
7.2 Flash Drum Control Loop: ....................................................................................................... 120
7.3 Reactor Control Loop ............................................................................................................... 121
7.4 Heat exchanger control loop .................................................................................................... 122
7.5 Distillation control loop ........................................................................................................... 123
7.6 Pump control loop .................................................................................................................... 124
8 CHAPTER 8: SAFETY AND ENVIROMRNTAL ASPECT .................................................................. 125
8.1 INTRODUCTION .................................................................................................................... 125
8.1.1 GENERAL PLANT SAFETY AND PERSONAL PROTECTIVE EQUIPMENT ..................................126
8.1.2 NFPA FIRE DIAMONDS AND SDS .................................................................................135
8.2 HAZARDOUS MATERIAL.................................................................................................... 138
8.2.1 Exposure and Health Effects of Materials............................................................................138
8.3 Equipment Safety ..................................................................................................................... 139
8.4 Hazard and Operability Study (HAZOP) ................................................................................. 142
8.4.1 What is HAZOP? ...................................................................................................................142
8.4.2 Objective of HAZOP Study: ..................................................................................................142
8.4.3 HAZOP Analysis: ...................................................................................................................143
8.5 Hazard Environmental Impact Assessment.............................................................................. 144
8.5.1 Introduction of Environmental Impact Assessment ............................................................144
8.5.2 Materials Leaving the Process and Their Impact on the Environment................................145
9 Chapter 9: Plant layout and site location ................................................................................. 148
9.1 Plant layout:.............................................................................................................................. 148
9.1.1 The main factors to be considered are: ................................................................................148
9.1.2 Why we need 3D plant representation? ...............................................................................149
9.1.3 The main principles for a plant layout: ................................................................................150
9.1.4 The minimum spacing between equipment’s ......................................................................150
9.2 Plant and site location: ............................................................................................................. 150
9.2.1 Main factors to be considered for plant and site location ....................................................152
9.2.2 Site Location Selected for N-OCTANE Production ............................................................153
10 CONCLUSION AND RECOMMENDATIONS ............................................................................ 155
References ..................................................................................................................................... 156
xi

Chapter 1................................................................................................................................................ 156

chapter 2................................................................................................................................................. 158
Chapter 3 & 4......................................................................................................................................... 159
Chapter 5................................................................................................................................................ 159
Chapter 6................................................................................................................................................ 159
Chapter 7................................................................................................................................................ 159
Chapter 8................................................................................................................................................ 160
Chapter 9................................................................................................................................................ 160
Appendix A: Equipment design ....................................................................................................... 161
Appendix B: Safety and environmental aspect. ............................................................................... 167
xii

LIST OF FIGURES:

Figure 1-1 molecular formula of iso-butane ..................................................................................................... 8

Figure 1-2: ethylene molecular formula ........................................................................................................... 9
Figure 1-3: N-octane global market ............................................................................................................... 12
Figure 1-4: N-octane market share. ................................................................................................................ 13
Figure 2-1: Pyramid of process diagram. ....................................................................................................... 20
Figure 2-2:Input-Output diagram. .................................................................................................................. 20
Figure 2-3: Block flow diagram ..................................................................................................................... 21
Figure 2-4: Process flow diagram. ................................................................................................................. 22
Figure 3-1: PFD. ........................................................................................................................................... 26
Figure 3-2: Mixer (MIX-101) ........................................................................................................................ 26
Figure 3-3: Plug flow reactor (R-101) ............................................................................................................ 28
Figure 3-4: Flash drum (V-101) ..................................................................................................................... 30
Figure 3-5: Distillation column (T-101) ......................................................................................................... 33
Figure 4-1: PFD ............................................................................................................................................ 39
Figure 4-2:Plug flow reactor (R-101)............................................................................................................. 40
Figure 4-3: Distillation column (T-101) ......................................................................................................... 43
Figure 4-4: Compressor (C-101) .................................................................................................................... 45
Figure 4-5: Compressor (C-102) .................................................................................................................... 46
Figure 4-6: Pump (P-101) .............................................................................................................................. 47
Figure 4-7: Heater (E-101) ............................................................................................................................ 48
Figure 4-8: Heater (E-102) ............................................................................................................................ 49
Figure 4-9: Heater (E-105) ............................................................................................................................ 50
Figure 4-10: Heater (E-106) .......................................................................................................................... 52
Figure 4-11: Cooler (E-103) .......................................................................................................................... 53
Figure 4-12: Cooler (E-104) .......................................................................................................................... 54
Figure 5-1 Distillation column (T-101) ............................................................................................................ 64
Figure 5-2 Distillation footprint ..................................................................................................................... 75
Figure 5-3 Flash Drum .................................................................................................................................. 78
Figure 5-4 Flash drum design ........................................................................................................................ 80
xiii

Figure 5-5 Thermosyphon reboiler ................................................................................................................ 81

Figure 5-6 Shell and Tube heat-exchanger ..................................................................................................... 85
Figure 5-7 Tube sheets for Shell and tube HE ................................................................................................ 86
Figure 5-8 baffles for shell and tube HE ........................................................................................................ 86
Figure 5-9 Double pipe HE............................................................................................................................ 96
Figure 6-1 Distribution of Equipment cost in N-octane process .................................................................... 109
Figure 6-2 Distribution of utility in N-octane process .................................................................................. 114
Figure 6-3 Discounted cash flow diagram .................................................................................................... 120
Figure 6-4 Non-discounted cash flow diagram ............................................................................................. 120
Figure 7-1 Compressor control loop ............................................................................................................ 119
Figure 7-2 Flash drum control loop.............................................................................................................. 120
Figure 7-3 : Reactor Control Loop ............................................................................................................... 121
Figure 7-4 Heat exchanger control loop ....................................................................................................... 122
Figure 7-5 Distillation control loop............................................................................................................... 123
Figure 7-6 Pump control loop ...................................................................................................................... 124
Figure 7-7 Pump control loop ...................................................................................................................... 124
Figure 8-1 Hard Hat (PPE) ............................................................................................................................ 126
Figure 8-2 Leggings, foot guard and safety shoes (PPE) ................................................................................ 127
Figure 8-3 Earplugs, Earmuffs, and other protection (PPE) ........................................................................... 128
Figure 8-4 Hand and arm protection ............................................................................................................ 129
Figure 8-5 eye protection and safety ........................................................................................................... 129
Figure 8-6 Surgical face mask....................................................................................................................... 130
Figure 8-7 Respirators ................................................................................................................................. 131
Figure 8-8 Face shield .................................................................................................................................. 132
Figure 8-9 Proximity sensors........................................................................................................................ 133
Figure 8-10 Body shield and protective clothing .......................................................................................... 134
Figure 8-11 NFPA rating explanation guide .................................................................................................. 135
Figure 9-1 Site layout .................................................................................................................................. 153
Figure 9-2:Plant location ............................................................................................................................. 154
xiv

LIST OF TABLES:

Table 1-1 Physical and chemical properties of N-octane .................................................................................. 2

Table 1-2: Physical properties of iso-butane .................................................................................................... 8
Table 1-3 physical properties of ethylene ....................................................................................................... 10
Table 2-1: Physical properties of ethylene ..................................................................................................... 23
Table 2-2: Physical properties of ethylene ..................................................................................................... 24
Table 3-1: Input-Output flowrates for (R-101) ............................................................................................... 29
Table 3-2: Material balance hand calculations for (V-101) ............................................................................. 31
Table 3-3: (V-101) Inputs .............................................................................................................................. 32
Table 3-4: The light and heavy key components ............................................................................................ 33
Table 3-5: Input-Output Molar flow for (T-101) ............................................................................................ 35
Table 3-6: Hand calculation summary for (MIX-101) and (R-101)................................................................. 35
Table 3-7: Hand calculations summary for (V-101) and (T-101) .................................................................... 36
Table 3-8: HYSYS Flowrates for (MIX-101) and (R-101) ............................................................................. 36
Table 3-9: HYSYS flow rates for (V-101) and (T-101) .................................................................................. 37
Table 3-10: Difference between scaled hand calculations and HYSYS calculation (%) .................................. 37
Table 4-1: CP Constent for components......................................................................................................... 40
Table 4-2: Cp values of each component [1] .................................................................................................. 41
Table 4-3: Results for Reactor Energy Balance .............................................................................................. 41
Table 4-4 : Heat Of Formation of each component [2] ................................................................................... 42
Table 4-5: Difference between scaled hand calculations and HYSYS calculation ........................................... 56
Table 5-1 Reactor Variables and design summary table ................................................................................. 57
Table 5-2 Physical properties for process stream............................................................................................ 58
Table 5-3 Physical properties for utility stream .............................................................................................. 58
Table 5-4 Default dimensions of the tube....................................................................................................... 59
Table 5-5 Towers design summary table ........................................................................................................ 75
Table 5-6 Pump and compressor summary..................................................................................................... 77
Table 5-7 Vessel design summary ................................................................................................................. 80
Table 5-8 Process stream physical properties ................................................................................................. 87
Table 5-9 Utility Stream physical properties .................................................................................................. 87
xv

Table 5-10 Specification sheet for E-101 ....................................................................................................... 99

Table 5-11 Specification sheet for E-102 ....................................................................................................... 94
Table 5-12 Specification sheet for E-103 ...................................................................................................... 95
Table 5-13 Process side physical properties for E-104 ................................................................................... 97
Table 5-14 Utility side physical properties for E-104 ..................................................................................... 97
Table 5-15Specification sheet for E-106 ...................................................................................................... 102
Table 5-16 Specification sheet for E-104 ..................................................................................................... 103
Table 5-17 Specification sheet for E-105 ..................................................................................................... 104
Table 5-18 Summary table for shell and tube HE ......................................................................................... 105
Table 5-19 Summary table for DP HE ......................................................................................................... 105
Table 6-1 Bare Module cost of equipment ................................................................................................... 108
Table 6-2 Nnp of non-particulate solid steps ................................................................................................ 111
Table 6-3 Cost of utility .............................................................................................................................. 113
Table 6-4 Cost of raw materials ................................................................................................................... 114
Table 6-5 Economic information calculated from given information ............................................................ 115
Table 6-6 product price ............................................................................................................................... 116
Table 6-7 Discounted profitabilty criterion .................................................................................................. 117
Table 6-8 Non-discounted Profitability criterion .......................................................................................... 117
Table 8-1 N-octane Information .................................................................................................................. 136
Table 8-2 N-octane NFPA's hazard diamond and its description. ................................................................. 136
Table 8-3 Ethylene Information ................................................................................................................... 136
Table 8-4 Ethylene NFPAS hazard and its description ................................................................................... 137
Table 8-5 iso-butane information ................................................................................................................. 137
Table 8-6 Iso-butane hazard diamond and its description ............................................................................ 138
Table 8-7 Example on HAZOP analysis ...................................................................................................... 143
Table 8-8 Control parameter ........................................................................................................................ 145
Table 9-1 Minimum space for major equipment .......................................................................................... 150
1

1 CHAPTER 1: INTRODUCTION
In this chapter we will discuss the definition of n-octane, properties of n-octane, uses and
application, historical back ground and the source of it.

1.1 BACKGROUND OF N-OCTANE

N-Octane, having the chemical formula 𝐶8 𝐻18, is an alkane group hydrocarbon, it is a boiling
point: (of 125-127) °C, a colorless liquid with a gasoline-like smell. Not as dense as water,
Produces irritating vapor.

Extremely flammable, readily condenses air into explosive combinations, unsuitable for oxidizing
agents, excellent solubility, or limitless miscibility with numerous organic solvents, including
(alcohols, ethers, esters, aromatics, and chlorinated hydrocarbons) but it is nearly insoluble in
water. [2]
Like other alkanes (paraffin, saturated hydrocarbons), works extremely well as a solvent for
nonpolar materials, including fats and oils. also it is used as inert solvent is specifically employed
in the pharmaceutical sector to wash, purify, and recrystallize active pharmaceutical components,
since octane does not disintegrate plastic, utilized in specialty adhesives for plastics and elastomers
(rubber), fuel quality can be determined using the octane number, in the petroleum industry, it
serves as an important chemical agent. , in addition, it is also used in the separation of
azeotropes.[1-3]
Although n-Octane has several applications, it also carries hazards much like other chemicals such
as (an irritant to the skin, eyes, and respiratory system, aspiration into the lungs may result from
consumption, lowering of consciousness may result from inhalation, headaches, blisters appear
after a five-hour cutaneous exposure).[3]
The group's modeling of oil refineries found that generating fuel with a higher octane would result
in a 6% rise in emissions from the refinery; nevertheless, this increase is small in comparison to
the overall emissions from fuel production.
2

1.2 PHYSICAL AND CHEMICAL PROPERTIES OF N-OCTANE

Table 1-1 Physical and chemical properties of N-octane

Molecular Formula C8 H18

Molar mass 114.23 g/mol.
Color / Form Colorless liquid
Odor Gasoline-like
Density 0.703 g/mL at 25 °C
Boiling Point 258.1 °F , 125.62 °C ,398.77at 760 mmHg
Melting Point -70.2 °F , -56.73 °C ,216.42 K
Flash Point 56 °F (13 °C)
Solubility in water 0.66 mg/L at 25 °C
Vapor pressure 14.1 mm Hg at 25 °C
Autoignition Temperature 428 F, 220 °C ,493.15 K
Viscosity 0.5151 cP at 25 °C
Refractive Index 1.3944 at 25 °C
1.3974 at 20 °C
Corrosivity Will attack some forms of plastics, rubber,
and coatings.
Heat of Vaporization 41.49 kJ/mol at 25 °C
Solubility Alcohols, ethers, esters, aromatics or
chlorinated hydrocarbons.
Surface Tension 21.14 mN/m at 25 °C
Decomposition When heated to decomposition it emits acrid
smoke and irritating fumes
Molecular Geometry Tetrahedral
Lone Pairs 0
Bond Pairs 25
LogP 5.15
3

1.3 HISTORICAL BACKGROUND OF N-OCTANE

The history of n-Octane production is closely tied to the evolution of the petroleum industry,
advancements in refining technology, and the need to meet the performance requirements of
internal combustion engines.

Early Petroleum Refining: In the late 19th century, the petroleum industry emerged, and early
refineries focused on separating crude oil into various fractions through distillation. Gasoline, a
byproduct of this process, was initially considered a waste product.

At the beginning of the 20th century, engine knocking was identified as an undesirable occurrence
during combustion in internal combustion engines. Researchers and engineers began investigating
the factors that contributed to this phenomenon. [5]

In the 1920s, Thomas Midgley Jr., an American chemist and engineer, conducted significant
research on knocking in engines. He discovered that adding certain chemicals to gasoline could
reduce knocking. Midgley and his team discovered tetraethyl lead (TEL) in 1921, which
effectively reduced knocking when added to gasoline. This led to the development of leaded
gasoline, which became widely used. [4]

In the 1930s the n-Octane rating system was introduced the initial method involved comparing the
knocking characteristics of a fuel to a mixture of iso-octane (high octane) and heptane (low octane).
The rating system compares a fuel's knocking characteristics to those of a mixture of octane and
heptane. Octane has a high resistance to knocking, while heptane has a low resistance. The
introduction of unleaded gasoline in the 1970s and 1980s was due to concerns about the
environmental and health impacts of leaded gasoline. [5]

This transition required improvements in refining processes and the development of additives to
achieve high octane ratings without the use of lead. Ongoing research and development in the
automotive and petroleum industries continue to explore ways to improve fuel efficiency, reduce
emissions, and enhance the performance of internal combustion engines.

Modern refining processes, such as hydrocracking and isomerization, have been developed to
produce higher-octane gasoline. These processes involve breaking down and rearranging
hydrocarbon molecules to achieve the desired chemical composition. [6]
4

Today, the octane rating remains a crucial factor in determining the quality of gasoline, with higher
octane fuels generally being associated with better performance in high-compression engines and
reduced knocking. The development of alternative fuels and engines, such as electric and
hydrogen-powered vehicles, is also influencing the future of automotive technology. [6]

Nowadays, Octane plays a major rule in several industries, like pharmaceutical, petrochemicals,
chemical and in Research and Development of other component.

1.4 USES AND APPLICATION OF N-OCTANE

n-Octane, a straight-chain alkane with the molecular formula C8H18, has several uses and
applications. Here are some of them:

Octane Rating Standard: n-Octane is a component of gasoline and is used as a reference standard
in the octane rating scale. The octane rating is a measure of a fuel's resistance to knocking or
pinging in internal combustion engines. The scale is set relative to a mixture of n-octane and iso-
octane, with n-octane assigned an octane rating of 0. [7]

Solvent: n-Octane is used as a solvent in various industries, including pharmaceuticals, paints, and
coatings. It is known for its ability to dissolve a wide range of substances and is often used in
laboratory settings for this purpose. [8]

Chemical Synthesis: n-Octane can be used as a reactant or solvent in certain chemical syntheses.
Its chemical properties make it suitable for specific reactions in organic chemistry.[9]

Extraction: In some processes, n-octane is used for the extraction of certain compounds, especially
in the isolation of natural products. Its ability to selectively extract certain substances from a
mixture makes it valuable in these applications.

Cleaning Agent: Due to its ability to dissolve oils and greases, n-octane is used as a cleaning agent
in industries where oil and grease removal is crucial. It is commonly used for cleaning equipment
and machinery.

Calibration Standard: In analytical chemistry, n-octane may be used as a calibration standard for
certain analytical instruments, particularly in gas chromatography.
5

Fuel Component: While n-octane itself is not a major component of gasoline, its properties
contribute to the overall characteristics of gasoline. Gasoline blends may contain different
hydrocarbons, including octane, to achieve desired fuel properties. [10]

It's important to handle n-octane and other hydrocarbons with care due to their flammable nature.
Additionally, in certain applications, regulatory guidelines may specify the use of substitutes or
alternative solvents for safety and environmental reasons.

1.5 SOURCES
Here are some of the sources of n-Octane:

Alkylation: Alkylation is a chemical reaction that combines two or more molecules of one
hydrocarbon (the alkylate) with one molecule of another hydrocarbon (the olefin) to produce a
new hydrocarbon with a higher-octane rating.

In the case of isobutane (the alkylate) and ethylene (light olefin), the alkylation reaction produces
n-octane as follows:

2 iso-butane + ethylene → n-octane

Petroleum: n-Octane is a component of crude oil and can be obtained through fractional
distillation. Fractional distillation is a process of separating a mixture of liquids into its individual
components based on their boiling points. N-octane has a boiling point of 125.6 °C, which is higher
than the boiling points of most other components of crude oil. This allows n-octane to be separated
from other components by heating the crude oil to a temperature above 125.6 °C. Once the crude
oil has been fractionated, the n-octane fraction can be further refined to produce a high-purity
product. This is done using a variety of processes, such as hydrogenation and adsorption.[13]

Natural Gas: n-Octane can also be obtained from natural gas through a process called gas-to-
liquids (GTL). GTL is a process of converting natural gas into liquid fuels. This is done by first
converting the natural gas into syngas, a mixture of carbon monoxide and hydrogen. The syngas
is then converted into liquid fuels using a variety of catalysts.

A number of different GTL processes have been developed, but most of them produce a mixture
of liquid hydrocarbons, including n-octane. The n-octane can be separated from the other
hydrocarbons using fractional distillation or other separation techniques. [14]
6

Biomass: n-Octane can be produced from biomass through a process called pyrolysis. Pyrolysis
is a process of heating biomass in the absence of oxygen to produce a variety of products, including
liquid fuels, gases.

The type of products produced by pyrolysis depends on the type of biomass used and the pyrolysis
temperature. For example, fast pyrolysis of biomass at high temperatures (400-600 °C) can
produce a liquid product called bio-oil. Bio-oil is a complex mixture of organic compounds,
including n-octane.

To produce n-Octane from bio-oil, the bio-oil must first be upgraded to remove impurities and to
improve its stability. This can be done using a variety of processes, such as hydrotreating and
catalytic cracking. [15]

Coal: n-Octane can also be produced from coal through a process called Fischer-Tropsch
synthesis. Fischer-Tropsch synthesis is a process of converting syngas into a variety of liquid
hydrocarbons, including n-octane.

Syngas can be produced from coal by gasification. Coal gasification is a process of heating coal in
the presence of oxygen and steam to produce a mixture of carbon monoxide and hydrogen.

The syngas is then converted into liquid hydrocarbons using a variety of Fischer-Tropsch catalysts.
The type of liquid hydrocarbons produced depends on the type of Fischer-Tropsch catalyst used
and the operating conditions.

Once the Fischer-Tropsch products have been cooled and condensed, they can be separated using
fractional distillation or other separation techniques. The n-octane fraction can then be further
refined to produce a high-purity product. [16]

1.6 ENVIRONMENT IMPACT OF N-OCTANE

n-Octane is a highly flammable liquid with vapors that are heavier than air. It can form explosive
mixtures with air and can travel to the source of ignition and flash back. Vapors may collect in low
or confined areas, such as sewers, basements, and tanks, creating a vapor explosion hazard. Runoff
to sewers may also create a fire or explosion hazard.[17]
7

1. Climate change: n-Octane is increased greenhouse gas emissions One of the primary
environmental impacts of octane is the increased greenhouse gas emissions that are associated with
its production and use. When octane is produced from crude oil, it requires a significant amount
of energy and resources. This process produces large amounts of carbon dioxide and other
greenhouse gases, which contribute to climate change. Additionally, when gasoline with high
levels of octane is burned in an engine, it produces more carbon dioxide emissions than gasoline
with lower levels of octane. This increased carbon dioxide output contributes to the overall
greenhouse gas emissions from transportation. .This contributes to climate change, which can lead
to more extreme weather events, rising sea levels, and other environmental problems.[18]

2. Air Pollution: In addition to greenhouse gas emissions, the production and use of octane also
contributes to air pollution. When gasoline is burned in an engine, it releases a number of pollutants
into the air, including nitrogen oxides, particulate matter, and volatile organic compounds. These
pollutants can have negative impacts on both human health and the environment. For example,
nitrogen oxides can contribute to the formation of smog, which can be harmful to human health,
N-octane is a volatile organic compound (VOC), which means that it can evaporate easily and
enter the atmosphere. VOCs contribute to the formation of ground-level ozone, a major component
of smog. Ozone can irritate the lungs and worsen asthma symptoms. It can also damage plants and
trees.[18]

3.Water pollution: n-Octane is toxic to aquatic life and can pollute lakes, rivers, and streams. It
can also contaminate groundwater.[18]

4.Health hazards: A skin, eye, and respiratory tract irritant, Ingestion can cause aspiration into
the lungs; Inhalation may cause lowering of consciousness Inhalation of vapor may cause
giddiness, vertigo, headache, anesthetic stupor, and convulsions; Five hour dermal exposure causes
blisters but no anesthesia, skin irritant, Inhalation may cause drowsiness or dizziness, An aspiration
hazard by ingestion (may cause lung injury).And chronic (long-term) health effects can occur at
some time after exposure to Octane and can last for months or years. like, Cancer Hazard.[19]
8

1.7 RAW MATERIALS

1.7.1 ISO-BUTANE
Definition:

Isobutane, also known as i-butane, 2-methylpropane, or methylpropane, is a chemical compound

with the molecular formula HC(CH3)3. It is an isomer of butane, meaning that it has the same
chemical formula as butane but a different structure. Isobutane is the simplest alkane with a tertiary
carbon atom, which means that it has three other carbon atoms bonded to it.[20]

Figure 1-1 Molecular formula of iso-butane

Physical properties:

Table 1-2: Physical properties of iso-butane

State Colorless gas

odor odorless

Molecular formula HC(CH3)3

Molecular mass 58.12 g/mol

Melting point -159.6 °C

Boiling point -11.7 °C

Density 0.551 g/cm³ (liquid at -11.7 °C)

Solubility in water: Slightly soluble

9

Chemical properties:
-Isobutane is a flammable gas.
-Isobutane is a non-toxic gas at low concentrations, but it can be irritating to the eyes and nose at
high concentrations.
-Isobutane is a relatively unreactive gas, but it can be converted to other chemicals, such as
isobutylene and isooctane, through catalytic reactions.[20,21]
Sources:
Isobutane is a natural gas liquid (NGL) that is produced during the extraction of natural gas from
underground reservoirs. It is also a byproduct of petroleum refining.[22,23]

1.7.2 ETHYLENE
Definition: Ethylene, also known as ethene, is a chemical compound with the molecular formula
C2H4. It is a colorless, flammable gas with a faint "sweet and musky" odor when pure. It is the
simplest alkene (a hydrocarbon with carbon–carbon double bonds). And it's also considered as
Light olefins.

Figure 1-2: Ethylene molecular formula

10

Physical properties:

Table 1-3 Physical properties of ethylene

State Colorless gas

odor sweet and musky odor when pure
Molecular formula C2H4
Molecular mass 28.05 g/mol
Melting point -169.2 °C
Boiling point -103.7 °C
Density 1.178 g/cm³ (liquid at -103.7 °C)
Solubility in water Slightly soluble
Chemical properties:
-Ethylene is a highly reactive gas. It is readily oxidized to form carbon dioxide and water.
-Ethylene is also a polymerizable gas, meaning that it can be converted to polyethylene, a common
plastic.
-Ethylene is a plant hormone that plays a role in fruit ripening and other plant growth processes.
Sources:
Petroleum: is a byproduct of petroleum refining and can be extracted from naphtha and other light
hydrocarbons through catalytic cracking and other processes.
Natural gas: Ethylene can also be produced from natural gas through a process called steam
cracking. Steam cracking is a process of heating natural gas to high temperatures in the presence
of steam to produce ethylene and other light hydrocarbons.[24-26]
11

1.8 MARKET STUDY OF N-OCTANE:

According to the International Energy Agency (IEA), global n-octane production in 2022 was
approximately 20 million tons. The top producers of n-octane in 2022 were:

United States: 5.5 million tons

China: 4.5 million tons

Russia: 3.5 million tons

Saudi Arabia: 2.5 million tons

India: 2 million tons

The IEA also forecasts that global n-Octane demand will grow at an average annual rate of 1.5%
from 2022 to 2030, driven by increasing gasoline demand in emerging markets and the use of n-
octane as a feedstock for petrochemicals.

The IEA report also highlights the following trends in n-Octane production:

-The United States is expected to remain the world's largest n-octane producer through 2030, but
its share of global production is expected to decline from 28% in 2022 to 25% in 2030.

-China's n-Octane production is expected to grow at an average annual rate of 2.5% from 2022 to
2030, driven by increasing gasoline demand in the country.

-Russia's n-Octane production is expected to decline at an average annual rate of 1% from 2022 to
2030, due to sanctions imposed on the country.

-Saudi Arabia's n-Octane production is expected to grow at an average annual rate of 2% from
2022 to 2030, driven by the country's plans to expand its refining capacity.

The global demand for n-Octane is expected to grow at an average annual rate of 1.5% from 2022
to 2030, according to the International Energy Agency (IEA). This means that global n-Octane
production will need to increase by approximately 300,000 tons per year to meet the growing
demand.
12

In 2022, global n-Octane production was approximately 20 million tons. Therefore, global n-
Octane production should reach approximately 23 million tons by 2030 in order to meet the
growing demand.

However, it is important to note that this is just a forecast. The actual amount of n-Octane that is
produced each year will depend on a number of factors, including the global economic outlook,
the price of oil, and the development of new technologies for producing n-Octane from renewable
feedstock's.

Figure 1-3: N-octane global market

Here are some of the factors that could drive growth in the global demand for n-Octane:

-Increasing gasoline demand in emerging markets.

-The use of n-octane as a feedstock for petrochemicals.

-The development of new technologies for producing n-octane from renewable feedstock.

Here are some of the factors that could constrain growth in the global demand for n-Octane:

-A decline in the global economy.

13

-A rise in the price of oil.

-The development of new gasoline additives that do not require n-octane.

Overall, the global demand for n-Octane is expected to grow in the coming years. This will require
an increase in global n-octane production. However, the actual amount of n-octane that is produced
each year will depend on a number of factors.

Figure 1-4: N-octane market share.

Global n-Octane production in 2022 was approximately 20 million tons.

Through research, we found that it is an approximate average for factories producing n-Octane
between (50 - 100). [27]

The production capacity for n-octane in our project:

𝟐𝟎 𝐦𝐢𝐥𝐥𝐢𝐨𝐧 𝐭𝐨𝐧𝐬
= 𝟐𝟎𝟎𝟎𝟎𝟎 𝒕𝒐𝒏𝒔/𝒚𝒆𝒂𝒓
𝟏𝟎𝟎

= 𝟐𝟎𝟕𝟏𝟏. 𝟗𝟖 𝒌𝒈/𝒉

𝒌𝒈 𝒌𝒈
= 𝟐𝟎𝟕𝟏𝟏. 𝟗𝟖 ∗ 𝟎. 𝟑 = 𝟔𝟐𝟏𝟑. 𝟓𝟗𝟒
𝒉 𝒉
14

Our plant cover 30% of approximate average for factories producing n-octane, So that the amount
of n-octane production needed is 6213.594 kg/h which is equal 54,471 ton/year.
15

2 CHAPTER 2: PROCESS SELECTION AND

DESCRIPTION
Process selection in chemical engineering is a crucial step in the design of a chemical plant. It
involves choosing the most efficient and cost-effective way to convert raw materials into desired
products. N-octane can be produced by many methods, therefore it's important to choose the
process wisely. In this chapter, a comparison between different alternatives of N-octane production
was made. There for the process description with flow diagrams (input output diagram, block flow,
and process flow diagrams), HYSES simulation was used.

2.1 PRODUCTION OF OCTANE FROM ETHYLENE AND ISO-

BUTANE (ALKYLATION):
Definition:

A process for generating high-octane alkylate from ethylene and isobutane involves their reaction
under catalytic conversion conditions. Ethylene and isobutane undergo contact with two distinct
catalytic materials: one facilitating ethylene dimerization and the other enabling alkylation. These
catalytic materials are separate entities. The outcome of this reaction is the retrieval of high-octane
alkylate resulting from the interaction of ethylene and isobutane in the presence of the two catalytic
materials.

Advantages:

1. Control ver Octane Rating: One of the significant advantages of this method is that it allows for
precise control over the octane rating of the final product. This is crucial for producing high-octane
gasoline, which is in demand for high-performance engines and compliance with environmental
standards.

2. High-Octane Yield: The production process from ethylene and isobutane is known for producing
high-octane components, making it a preferred method for enhancing the octane rating of gasoline.

3. Utilization of Isobutane: Isobutane, a byproduct of the oil and gas industry, is used as a feedstock
in this process, which can help manage excess isobutane production and reduce waste.
16

4. Customization: Producers can customize the octane blend to meet specific market demands,
allowing flexibility in catering to various gasoline formulations.

5. In the case of Jordan, the most viable option for producing n-octane is likely to be the alkylation
of isobutane process. This is because Jordan has a relatively abundant supply of isobutane, which
is produced as a byproduct of the oil refining process.

Disadvantages:

1. Requires an alkylation catalyst, which can be corrosive and hazardous

2. Can be sensitive to catalyst deactivation

2.2 HIGH-OCTANE GASOLINE PRODUCTION FROM

CATALYTIC NAPHTHA REFORMING:
Definition:

Catalytic reforming is a process used to convert low-octane naphthas into high-octane gasoline
blending components called reformates. Reforming is the total effect of several reactions that occur
simultaneously including cracking, polymerization, dehydrogenation, and isomerization.

Disadvantages:

1. Limited Control Over Octane Rating: Unlike the synthetic production method, naphtha
reforming may provide less precise control over the octane rating of the final product, which can
impact its application in certain markets.

2. Economic Sensitivity: The economic viability of this method can be sensitive to market
conditions, including changes in crude oil prices, demand for high-octane gasoline, and regulatory
changes.

3. Safety Hazards: Operating at high temperatures and pressures poses safety risks, and there's a
potential for accidents or equipment failures.
17

4. Complexity: Catalytic naphtha reforming is a complex process, requiring skilled operators and
a well-maintained infrastructure.

5. Catalyst Deactivation: The catalyst used in the process can become deactivated over time due
to various contaminants and coke buildup, necessitating frequent regeneration or replacement. [1-
3]

2.3 THE FISCHER-TROPSCH:

Definition:

The Fischer-Tropsch process is a catalytic chemical reaction used to convert carbon monoxide
(CO) and hydrogen (H2) gases into hydrocarbons. The Fischer-Tropsch (FT) process is not
commonly used for the direct production of octane. Octane is a specific hydrocarbon compound
used to increase the octane rating of gasoline, and its production usually involves different
methods, such as the production of octane from ethylene and

isobutane, as previously discussed.

Alkylation of isobutane is better than Fischer-Tropsch to produce n-octane because of the

following reasons:

1. Higher yield of n-octane: The alkylation of isobutane produces a higher yield of noctane than
the Fischer-Tropsch process.

2. Better selectivity: The alkylation of isobutane is more selective for the production of n-octane
than the Fischer-Tropsch process. The Fischer-Tropsch process produces a mixture of
hydrocarbons, and n-octane is only one of the components of the mixture.

3. Lower cost: The alkylation of isobutane is a less expensive process than the FischerTropsch
process.

4. More mature technology: The alkylation of isobutane is a more mature technology than the
Fischer-Tropsch process. This means that there is more experience with the alkylation of isobutane
and that the technology is more reliable.[4-6]
18

2.4 PRODUCTION OF N-OCTANE FROM BIOMASS

Biomass can be used to produce n-octane through a variety of processes, including:

1. Pyrolysis: Biomass is heated in the absence of oxygen to produce a liquid bio-oil. Bio-oil
can then be upgraded to n-octane through catalytic cracking or other processes.
2. Fermentation: Biomass is fermented by microorganisms to produce a mixture of alcohols
and other organic compounds. These compounds can then be used to produce n-octane
through a variety of processes.

Disadvantages:

1-High cost: Biomass is currently more expensive than fossil fuels, so n-octane produced from
biomass is also more expensive.

2-Low yields: The conversion of biomass to n-octane is not very efficient, so the yields are low.

3-Energy-intensive processes: The processes used to produce n-octane from biomass are energy-
intensive, so they have a high environmental impact. [7-11]

2.5 CONCLUSION
After research and through the information described above, we selected production of n octane
from ethylene and isobutane. studying advantages and disadvantages for each method this method
to use it.

2.6 PROCESS DESCRIPTION

The liquid isobutane feed stream (No. 1) at -11.99°C and 100 kPa is pressurized with pump (P-
101) to 500 kPa, then fed to a heater (E-101) to increase its temperature to 200°C the outlet from
heater stream (No. 3) . The ethylene gas feed stream (No. 4) at 25°C and 100 kPa. Then ethylene
stream is pressurized with a compressor (C-101) to 500 kPa and fed to heater (E-102) to increase
its temperature to 200°C. The outlet stream (No. 6) from heater (E-102) is then mixed with stream
(No. 3) and two recycled streams (No. 17) and (No. 20) are also introduced into the mixer. The
19

outlet stream from mixer stream (No. 7) is introduced into an iso thermal, isobaric plug flow reactor
(R-101), operating at 199.6°C and 500 kPa, achieving an 88.12% conversion of isobutane.

Reactions Involved:

2 𝐶2𝐻4 (𝑒𝑡ℎ𝑦𝑙𝑒𝑛𝑒) + 𝐶4𝐻10(𝑖 − 𝑏𝑢𝑡𝑎𝑛𝑒) → 𝐶8𝐻18(𝑛 − O𝑐𝑡𝑎𝑛𝑒)

The reactor effluents are cooled from 199.6°C and fed to phase separator (V-101) at 56.67°C and
100 kPa to separate the gases mixture stream (No. 11) from the liquid mixture stream (No. 12).
The separated gas stream (No. 11) is recycled back to the mixer after being pressurized by a
compressor(C-102) from 100 kPa to 500 kPa and heated by a heater (E-106) to 200°C. Stream
(No. 12) contains (isobutane, ethylene, and n-octane) is introduced into cooler (E-104) to decrease
the temperature from 56.67°C to 44.86°C bubble point temperature before being introduced into
a distillation column (T-101). The distillation column separates the light key component (ethylene)
at the top and the heavy component (n-octane) at the bottom. The top stream (D) in distillation is
recycled back to the mixer after being heated by a heater (E-105) to 200°C.
20

2.7 FLOW DIAGRAMS.

Figure 2-1: Pyramid of process diagram.

2.7.1 INPUT-OUTPUT DIAGRAM

In this diagram we will represent only the reactants and products streams of the reaction:

Figure 2-2: Input-Output diagram.

21

2.7.2 BLOCK FLOW DIAGRAM (BFD)

A block flow diagram should include major process steps and connections between them,
representing the overall flow of materials or information within a system or process. It provides a
simplified visual representation to understand the sequence of operations and interactions in a
system.

Figure 2-3: Block flow diagram

22

2.7.3 PROCESS FLOW DIAGRAM (PFD)

A process flow diagram should depict the sequence of steps in a process, including inputs, outputs, decision points, and connections
between activities, providing a visual representation of the workflow for analysis and optimization. It should be clear, concise, and
organized, with annotations to explain key elements and their relationships. [12]

Figure 2-4: Process flow diagram.

23

2.7.4 PROCESS FLOW TABLES

Table 2-1: Physical properties of ethylene

Component/Stream S1 S2 S3 S4 S5 S6 S7 S8 S9

Vapour Fraction 0.00 0.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00

Temperature -11.99 -11.72 200.00 25.00 151.31 200.00 199.55 199.60 196.09

Pressure 100.00 500.00 500.00 100.00 500.00 500.00 500.00 500.00 100.00

Molar Flow 53.45 53.45 53.45 106.90 106.90 106.90 210.35 103.48 103.48

Mass Flow 3106.73 3106.73 3106.73 2998.95 2998.95 2998.95 8114.84 8114.86 8114.86

Liquid Volume Flow 5.53 5.53 5.53 7.83 7.83 7.83 17.63 12.94 12.94

Component Flow (kmol/h)

Ethylene 0 0 0 1 1 1 0.69 0.37 0.37

Iso-butane 1 1 1 0 0 0 0.29 0.07 0.07
n-octane 0 0 0 0 0 0 0.02 0.56 0.56
24

Table 2-2: Physical properties of ethylene

Component/Stream S10 S11 S12 S13 S14 S15 S16 S17 S18

Vapour Fraction 0.47 1.00 0.00 0.00 0.00 0.00 1.00 1.00 1.00
Temperature 56.67 56.67 56.67 -41.85 194.53 44.86 200.00 200.00 143.47
Pressure 100.00 100.00 100.00 500.00 500.00 100.00 500.00 500.00 500.00
Molar Flow 103.48 48.51 54.97 1.53 53.44 54.97 1.53 1.53 48.51

Mass Flow 8114.86 1939.35 6175.51 71.40 6104.11 6175.51 71.40 71.48 1939.35

Liquid Volume Flow 12.94 4.14 8.79 0.14 8.65 8.79 0.14 0.14 4.14

Component Flow (kmol/h)

Ethylene 0.37 0.78 0.01 0.38 0.00 0.01 0.38 0.38 0.78
Iso-butane 0.07 0.13 0.02 0.62 0.00 0.02 0.62 0.62 0.13
n-octane 0.56 0.09 0.97 0.00 1.00 0.97 0.00 0.00 0.09
25

3 CHAPTER 3: MATERIALS BALANCE

A basic framework for studying and understanding the movement of materials via processes is
provided by the material balance. It is essential to chemical engineering, environmental
engineering, and other related fields because it allows engineers to measure the amount of
compounds entering a system and their accumulation over time. Through the use of mass
conservation concepts. Which states that while material can be transformed between its basic
phases, it cannot be generated or destroyed.

Any process's general conservation equation can be expressed as:

𝑴𝒂𝒕𝒆𝒓𝒊𝒂𝒍 𝒊𝒏 + 𝑮𝒆𝒏𝒆𝒓𝒂𝒕𝒊𝒐𝒏 – 𝑴𝒂𝒕𝒆𝒓𝒊𝒂𝒍 𝒐𝒖𝒕 − 𝑪𝒐𝒏𝒔𝒖𝒎𝒑𝒕𝒊𝒐𝒏 = 𝒂𝒄𝒄𝒖𝒎𝒖𝒍𝒂𝒕𝒊𝒐𝒏

The accumulation term for a process at a steady state is zero. When a chemical reaction occurs, a
certain chemical species may accumulate or be consumed.

The reaction is:

2C2H4 (ethylene) + C4H10 (i-butane) →C8H18 (n-octane)

We assume a Feed of 210.4kmol/h:

26

Figure 3-1: PFD.

3.1 MIXER (MIX-101) MATERIAL BALANCE

Figure 3-2: Mixer (MIX-101)

O.M.B (overall material balance)

Mass in =Mass out

m3+m6+ m17+m20=m7

3107+2999+71.48+1938= 8115.48 kg/h

Iso butane balance

27

xi3*m3+xi6 *m6 + xi17*m17+xi20 *m20= xi7*m7

1*3107+0*2999+0.7714*71.48+0.1873*1938= xi7*8115.48

xi7= 3525.127/8115.48

xi7=0.43437

Ethylene balance

xE3*m3+xE6 *m6 + xE17*m17+xE20 *m20= xE7*m7

0*3107+1*2999+0.2284*71.48+0.5458*1938= xE7*8115.48

xE7= 4073.08/8115.48 xE7= 0.5018

Octane balance

xO3*m3+xO6 *m6 + xO17*m17+xO20 *m20= xO7*m7

0*3107+0*2999+0.0002*71.48+0.2669*1938= xO7*8115.48

xO7=517.266/8115.48

xO7=0.06373
28

3.2 PLUG FLOW REACTOR (R-101) MATERIAL BALANCE

Figure 3-3: Plug flow reactor (R-101)

Assumptions: molar flow rate for (ethylene =145.1835 kmol/h, iso-butane=60.6148 kmol/h, n-
octane=4.5272 kmol/h) and single pass conversion for iso-butane = 88.12%

Calculating the molar flow rate of iso-butane in stream 8:

𝐹𝑖𝑛(𝐼𝑠𝑜−𝑏𝑢𝑡𝑎𝑛𝑒) −𝐹𝑜𝑢𝑡(𝐼𝑠𝑜−𝑏𝑢𝑡𝑎𝑛𝑒)
Conversion = 𝐹𝑖𝑛(𝐼𝑠𝑜−𝑏𝑢𝑡𝑎𝑛𝑒)

60.6418−𝐹𝑜𝑢𝑡(𝐼𝑠𝑜−𝑏𝑢𝑡𝑎𝑛𝑒 )
0.8812 = 60.6418

𝐹𝑜𝑢𝑡(𝐼𝑠𝑜−𝑏𝑢𝑡𝑎𝑛𝑒 ) = 7.204𝑘𝑚𝑜𝑙/ℎ

Calculating the extent of the reaction:

𝐹 −𝐹𝑖𝑛,𝑖𝑠𝑜−𝑏𝑢𝑡𝑎𝑛𝑒
ξ̇ = 𝑜𝑢𝑡,𝑖𝑠𝑜−𝑏𝑢𝑡𝑎𝑛𝑒
𝒱 𝑖𝑠𝑜−𝑏𝑢𝑡𝑎𝑛𝑒

7.20−60.64
= = 53.44 Kmole /h
−1
29

Calculating the molar flow rates for ethylene and m-octane in stream 8:

𝐹 −𝐹 Where 𝜐 is the
ξ̇ = 𝑜𝑢𝑡,𝑒𝑡ℎ𝑒𝑙𝑦𝑛𝑒 𝑖𝑛,𝑒𝑡ℎ𝑦𝑙𝑒𝑛𝑒
𝒱𝑒𝑡ℎ𝑦𝑙𝑒𝑛𝑒 stoic.coeff

𝐹𝑜𝑢𝑡(𝑒𝑡ℎ𝑦𝑙𝑒𝑛𝑒)−145
53.44 = = 38.12 𝑘𝑚𝑜𝑙/ℎ
−2

𝐹 −𝐹𝑖𝑛,𝑛−𝑜𝑐𝑡𝑎𝑛𝑒
ξ̇ = 𝑜𝑢𝑡,𝑛−𝑜𝑐𝑡𝑎𝑛𝑒
𝒱𝑛−𝑜𝑐𝑡𝑎𝑛𝑒

𝐹𝑜𝑢𝑡(𝑛−𝑜𝑐𝑡𝑎𝑛𝑒)−4.5272
53.44 = = 57.9672 𝑘𝑚𝑜𝑙/ℎ
1

Table 3-1: Input-Output flowrates for (R-101)

S.no/Component Mole Flow Ethylene Iso-butane N-Octane

7 (kmol/h) 210.4 145.1835 60.6148 4.5272
8 (kmol/h) 103.2912 38.12 7.204 57.6972
30

3.3 FLASH DRUM (V -101) MATERIAL BALANCE

Figure 3-4: Flash drum (V-101)

The Rachford - Rice Equation for Flash Calculation:

Feed Information Temperature (56.67 Cͦ), Pressure (100 kpa), Molar flow (103.5 kmole
/h),𝑧𝑒𝑡ℎ𝑦𝑙𝑒𝑛𝑒 = 0.3702, 𝑧𝑖𝑠𝑜_𝑏𝑢𝑡𝑎𝑛𝑒 = 0.0696 , 𝑧𝑛_𝑜𝑐𝑡𝑎𝑛𝑒 =0.5602 .

Total Material Balance:

F = L +V

Component Material Balance:

F𝑧𝑖 =L𝑥𝑖 +V𝑦𝑖

Equilibrium Relationship:

𝑦𝑖 = 𝑘𝑖 𝑥𝑖

By Substituting Equilibrium Relationship in Component Material Balance:

F𝑧𝑖 =L𝑥𝑖 +V(𝑘𝑖 𝑥𝑖 )

F 𝑧𝑖 = 𝑥𝑖 (L + V𝑘𝑖 )
F𝑧𝑖
𝑥𝑖 =
L + V𝑘𝑖
31

By Substituting Total Material Balance in Component Material Balance (L = F -V):

F𝑧𝑖
𝑥𝑖 =
(F − V) + V𝑘𝑖

𝑧𝑖
𝑥𝑖 =
V V
(1 − 𝐹 ) + 𝐹 𝑘𝑖
𝑧𝑖
𝑥𝑖 =
V
(𝑘
𝐹 𝑖 − 1) + 1
𝑘𝑖 𝑧𝑖
𝑦𝑖 =
V
(𝑘
𝐹 𝑖 − 1) + 1
∑ 𝑦𝑖 =1 , ∑ 𝑥𝑖 =1
𝑧𝑖 (𝑘𝑖 −1)
∑ 𝑦𝑖 − ∑ 𝑥𝑖 = ∑ V =0
(𝑘𝑖−1)+1
𝐹

𝑧𝑖 (𝑘𝑖 −1) V
∑V Non linear algebraic equation with one variable vapor fraction (𝐹 ) , through the solver
(𝑘𝑖 −1)+1
𝐹

in excel, this type of equation can be solved.

Table 3-2: Material balance hand calculations for (V-101)

Component Zi A B C Pi(mmhg) Pi(Kpa)

Ethylene 0.3702 6.74755 584.999 255 74228.0302 9872.328
Iso-butane 0.0696 6.74809 882.816 240 5920.23799 787.39165
N-octane 0.5602 6.92377 1355.12 209.52 68.0722641 9.0536111
𝑧𝑖 ∗ 𝑝𝑖 𝑧𝑖 /𝑝𝑖
𝑘𝑖 ki-1 zi*(ki-1) f xi yi
3654.735831 3.7E-05
98.7233 97.7233 36.1771583 0.77383 0.00792 0.78175
54.80245906 8.8E-05
7.87392 6.87392 0.47842459 0.11342 0.0165 0.12992
5.07183295 0.06188
0.09054 -0.9095 -0.5094817 -0.8873 0.97558 0.08833
32

Through this calculation vapor fraction (0.468).

V
Vapor Fraction ( ) = 0.468 , F = 103.5, Vapor =0.468*103.5 = 48.438 kmole /h.
𝐹

Liquid = F – V =103.5 – 48.438 = 55.062 kmole /h.

Table 3-3: (V-101) Inputs

Component Feed Vapor Liquid

Ethylene 38.31 37.87 0.44

Iso-butane 7.2 6.29 0.909
N-octane 57.96 4.28 53.72
33

3.4 DISTILLATION COLUMN (T -101) MATERIAL BALANCE

Figure 3-5: Distillation column (T-101)

The light and heavy key components are determined according to boiling point:

Table 3-4: The light and heavy key components

Lighter than light key
Ethylene B.P=-103.7 C
(LLK)
Iso-butane B.P=-11.7 Light key (LK)
n-Octane B.P=125 Heavy key (HK)

Feed Information Temperature (44.86 Cͦ) , Pressure (100 kpa ) , Molar flow (54.97 kmol /h) ,
𝑧𝑒𝑡ℎ𝑦𝑙𝑒𝑛𝑒 = 0.01058, 𝑧𝑖𝑠𝑜_𝑏𝑢𝑡𝑎𝑛𝑒 = 0.01733, 𝑧𝑛_𝑜𝑐𝑡𝑎𝑛𝑒 = 0.97208

Overall material balance:

𝐹 =𝐵+𝐷

Component material balance:

𝐹𝑧 = 𝐵 𝑥𝑏 + 𝐷 𝑥𝑑
34

from this we get this formula :

𝑧 − 𝑥𝑑
𝐵= ×𝐹
𝑥𝑏 − 𝑥𝑑

𝐷 =𝐹−𝐵

Assumption:

Mole fraction of n-Octane in the bottom, Xb=0.9999

Mole fraction of n-Octane in the distillate, Xd =0.0001

Solving equation to find D and B

𝐵𝑂 = 𝐹𝑂𝑋𝑂𝑏

𝐵𝑂 = 53.4334 ∗ 0.9999 = 53.4281 kmol/h

𝐵𝐼 = 𝐹𝑋𝐼𝑏

𝐵𝐼 = 53.4334 ∗ 0.0001 = 0.005343 𝑘𝑚𝑜𝑙/ℎ

𝐵 = 𝐵𝐼 + 𝐵𝑂

𝐵 = 53.4281 + 0.005343 = 53.43349 𝑘𝑚𝑜𝑙/ℎ

𝐷 =𝐹−𝐵

𝐷 = 54.968 − 53.433 = 1.5345 𝑘𝑚𝑜𝑙/ℎ

𝐷𝐼 = 𝐹𝐼 − 𝐵𝐼

𝐷𝐼 = 0.9526 − 0.005343 = 0.947275 𝑘𝑚𝑜𝑙/ℎ

𝑋𝐸𝐹 ∗ 𝐹 = 𝑋𝐸𝐷 ∗ 𝐷

0.58191494 = 𝑋𝐸𝐷 ∗ 1.5345

𝑋𝐸𝐷 = 0.37921

𝐷𝐸 = 0.37921 ∗ 1.5345 = 0.5819 𝑘𝑚𝑜𝑙/ℎ

35

𝐷𝑂 = 0.0001 ∗ 1.5345 = 0.000153 𝑘𝑚𝑜𝑙/ℎ

Table 3-5: Input-Output Molar flow for (T-101)

S.no/Component Mole Flow Ethylene Iso-butane N-Octane

13 (kmol/h) 54.968 0.5819 0.9526 53.4334
D (kmol/h) 1.5345 0.5819 0.9472 0.000153
B (kmol/h) 53.43349 0 0.0053 53.42814

3.5 RESULT FOR ALL STREAM FLOWRATES:

3.5.1 HAND CALCULATION

Table 3-6: Hand calculation summary for (MIX-101) and (R-101)

Component/S.no Mixer (MIX-101) Reactor (R-101)

Kmol/h

3 6 17 20 7 8

Ethylene 0 106.916 0.582043 37.70982 145.2081 38.12

Iso-butane 53.458 0 0.948737 6.245482 60.65258 7.204

N-Octane 0 0 0.000153 4.528164 4.528317 57.6972

Total flowrate 53.458 106.916 1.530933 48.48346 210.389 103.2912

36

Table 3-7: Hand calculations summary for (V-101) and (T-101)

Distillation Column
Flash Drum (V-101)
Component/S.no (T-101)

10 11 12 13 D B

Ethylene 38.3096 37.86654 0.436015 0.5819 0.5819 0

Iso-butane 7.2048 6.293138 0.908536 0.9526 0.9472 0.0053

N-Octane 57.964 4.278303 53.71746 53.4334 0.000153 53.42814

Total flowreate 103.5 48.438 55.062 54.968 1.5345 53.43349

3.5.2 HYSYS CALCULATION

Table 3-8: HYSYS Flowrates for (MIX-101) and (R-101)

Component/S.no Mixer (MIX-100) Reactor (R-101)

Kmol/h

3 6 17 20 7 8

Ethylene 0 106.9 0.5819 37.701 145.1835 38.3096

Iso-butane 53.45 0 0.9486 6.2431 60.6418 7.2048

N-Octane 0 0 0.0001529 4.5270 4.5272 57.6941

Total flowrate 53.45 106.9 1.531 48.47 210.3524 103.4786

37

Table 3-9: HYSYS flow rates for (V-101) and (T-101)

Distillation Column
Flash Drum (V-101)
Component/S.no (T-101)

10 11 12 13 15 14

Ethylene 38.3096 37.7277 0.5819 0.5819 0.5819 0

Iso-butane 7.2048 6.2522 0.9526 0.9526 0.9473 0.0053

N-Octane 57.9641 4.5306 53.4335 53.4334 0.0001529 53.43

Total flowreate 103.4786 48.5105 55.062 54.968 1.5293 53.4387

3.5.3 ERROR BETWEEN SCALED HAND CALCULATION AND HYSYS

CALCULATION
Table 3-10: Difference between scaled hand calculations and HYSYS calculation (%)

Component/S.no Mixer (MIX-100) Reactor (R-101)

Kmol/h

3 6 17 20 7 8

Ethylene 0 0.0150 0.0246 0.0234 0.0169 0.4949

Iso-butane 0.0150 0 0.0144 0.0382 0.0178 0.0111

N-Octane 0 0 0.0654 0.0257 0.0247 0.0054

Total flowrate 0.0150 0.0150 0.0044 0.0278 0.0174 0.1811

38

Distillation Column
Flash Drum (V-101)
Component/S.no (T-101)

10 11 12 13 15 14

Ethylene 0.0000 0.3680 25.0705 0.0000 0.0000 0

Iso-butane 0.0000 0.6548 4.6257 0.0000 0.0106 0.0000

N-Octane 0.0002 5.5687 0.5314 0.0000 0.0654 0.0035

Total flowreate 0.0207 0.1495 0.0000 0.0000 0.3400 0.0097

39

4 CHAPTER 4:PROCESS ENERGY BALANCE

An essential part of engineering studies is the energy balance, which offers a methodical way to
understand how energy is transferred, converted, and used in different systems. This chapter
examines the conservation of energy principle, which has its roots in the first rule of
thermodynamics and states that energy can only be changed from one form to another. Engineers
can improve system performance, increase energy efficiency, and create sustainable solutions for
a variety of engineering problems by utilizing the concepts of energy balance.

4.1 PROCESS ENERGY BALANCE

The main energy balance equation for steady state systems is given by the following equation:

𝑄̇ − 𝑊̇ = ∆𝐻̇ + ∆𝐾̇𝑒 + ∆𝑃̇𝑒

Where:

𝑄̇: Heat duty rate (kJ/h)

Ẇ: Work rate done by system (kJ/h)

∆𝐻̇: Enthalpy change rate (kJ/h)

∆𝐾̇𝑒: Kinetic energy change rate (kJ/h)

∆𝑃̇𝑒: Potential energy change rate (kJ/h)

Figure 4-1: PFD

40

4.2 PLUG FLOW REACTOR (R-101) ENERGY BALANCE

A reactor in this process is iso-thermal reactor the inlet temperature equals the outlet temperature
(199.6 Cͦ), and constant pressure (500 Kpa), the type of this reactor is a Plug Flow Reactor (PFR)
, no phase change all component in gas phase .

Figure 4-2: Plug flow reactor (R-101)

Table 4-1: CP Constent for components.

COMPONENT A B C D E
ISO-BUTANE 6.772 0.34147 -0.00010271 -3.6849E-08 2.0429E-11
EYHYLENE 32.083 -0.014831 0.00024774 -2.3766E-07 6.8274E-11
N-OCTANE 29.053 0.58016 -0.000057103 -1.9548E-07 7.6614E-11

To calculate cp for each component this form must be use (this form for gas component):

Cp = A +BT+C𝑇2 +D𝑇3 +E𝑇4

Cp of iso-butane at (298) K:

= 6.772 +0.34147*(298)+ -0.00010271*(2982 )+ -3.6849E-08*(2983 )+ 2.0429E-11*(2984 )

= 98.59495043 Joule /(mole .k)

NOTE : 𝑻𝒊𝒏 =𝑻𝒐𝒖𝒕 =T =472.6 K

41

Table 4-2: Cp values of each component [1]

COMPONENT Cp at 𝑻𝒓𝒆𝒇 (298 K) Cp at 𝑻𝒎𝒊𝒅 (385.3K) Cp at T (472.6)
KJ /(Kmole .K) KJ /(Kmole .K) KJ /(Kmole .K)

ISO-BUTANE 98.59495043 121.4349374 142.3398604

EYHYLENE 43.91274672 51.05764926 58.72633697
N-OCTANE 192.3007918 234.6183903 273.6705473

To calculate H (enthalpy) use Simpsons rule to solve integration term:

𝐻1 = 𝐻4 , 𝐻3 = 𝐻6 , 𝐻2 = 𝐻5
T
H = ∫T cp dT
ref

T h
∫T cp dT = 3 [cp(𝑇𝑟𝑒𝑓 )+4cp(𝑇𝑚𝑖𝑑 )+cp(T)]
ref

𝑇−𝑇𝑟𝑒𝑓 472.6−298
h= = = 87 .3 K
2 2

87.3
𝐻1 = [98.59+4*121.43+142.34]
3

𝐻1 =21146.23 KJ/(Kmole .h)

Table 4-3: Results for Reactor Energy Balance

COMPONEN 𝑭𝒊𝒏 ̂𝒊𝒏
𝑯 𝑭𝒊𝒏 ∗ 𝑯𝒊𝒏 𝑭𝒐𝒖𝒕 ̂
𝑯𝒐𝒖𝒕 𝑭𝒐𝒖𝒕 ∗ 𝑯𝒐𝒖𝒕
Kmole /h KJ/(Kmole .h) KJ/h Kmole /h KJ/(Kmole.h) KJ/h
ISO-BUTANE 60.64 21146.23 1282344.4 7.20 21146.23 152356.12
EYHYLENE 145.18 8929.91 1296475.0 38.31 8929.91 342101.91
N-OCTANE 4.52718 40869.35 185023.07 57.96 40869.35 2368960.2

Q̇ - 𝑊̇ 𝑠 = ∆Ḣ+ ∆𝐸̇ 𝐾 +∆𝐸̇ 𝑃

𝑊̇ 𝑠 = 0 ( NO moving parts ) , ∆𝐸̇ 𝑃 = 0 (horizontal unit ) , ∆𝐸̇ 𝐾 = 0 (no change in velocity ) .

Q̇ ≈ ∆Ḣ

̂
∆Ḣ = ξ̇ ∆H
̇ 𝑟𝑥𝑛 +∑ 𝐹𝑜𝑢𝑡 𝐻
̂ ̂
𝑜𝑢𝑡 -∑ 𝐹𝑖𝑛 𝐻𝑖𝑛
42

𝐹 −𝐹𝑖𝑛,𝑖𝑠𝑜−𝑏𝑢𝑡𝑎𝑛𝑒
ξ̇ = 𝑜𝑢𝑡,𝑖𝑠𝑜−𝑏𝑢𝑡𝑎𝑛𝑒
𝒱 𝑖𝑠𝑜−𝑏𝑢𝑡𝑎𝑛𝑒

7.20−60.64
= = 53.44 Kmole /h
−1

Table 4-4 : Heat Of Formation of each component [2]

COMPONEN Heat of formation |𝓥|
(KJ/Kmole)
ISO-BUTANE -134.5 *103 1
EYHYLENE 52.28*103 2
N-OCTANE -208.4*103 1

̂ ̂
̇ 𝑟𝑥𝑛 = ∑𝑃𝑟𝑜𝑑𝑢𝑐𝑡𝑠 |𝒱| ∆H
∆H ̂
̇ 𝑓𝑖 - ∑𝑅𝑒𝑎𝑐𝑡𝑎𝑛𝑡𝑠 |𝒱| ∆H
̇ 𝑓𝑖

= -208.4*103- (2*52.28*103 +-134.5 *103 ) = -178460 KJ/Kmole

∑ 𝐹𝑖𝑛 𝐻̂
𝑖𝑛 = 2763842.578 KJ/h

̂
∑ 𝐹𝑜𝑢𝑡 𝐻𝑜𝑢𝑡 =2863418.263 KJ/h

̂
∆Ḣ = ξ̇ ∆H
̇ 𝑟𝑥𝑛 +∑ 𝐹𝑜𝑢𝑡 𝐻
̂ ̂
𝑜𝑢𝑡 -∑ 𝐹𝑖𝑛 𝐻𝑖𝑛

(53.44)*(-178460) + (2863418.263) – (2763842.578)

∆Ḣ = -2622 KW.

43

4.3 DISTILLATION COLUMN (T-101) ENERGY BALANCE

Figure 4-3: Distillation column (T-101)

𝐹ℎ𝐹 + 𝑄𝐶 + 𝑄𝑅 = 𝐷ℎ𝐷 + 𝐵ℎ𝐵

Reboiler (Q-RE): -

𝐾𝐽
𝑄𝑅 ( ) = 𝑚 ∗ 𝐶𝑝 ∗ (𝑇𝑜𝑢𝑡 − 𝑇𝑖𝑛 )
ℎ𝑟

𝑘𝑗 𝑘𝑔 𝑘𝑗
𝑄𝑅 ( ) = 6104 ∗ 2.6759 (194.5 − 44.86)𝐶°
ℎ𝑟 ℎ𝑟 𝑘𝑔. 𝐶°

𝑘𝑗
𝑄𝑅 = 2.44 ∗ 106
ℎ𝑟

𝑄𝑅 = 6.73 ∗ 102 KW
44

Condenser (Q-CON): -

𝐹ℎ𝐹 + 𝑄𝐶 + 𝑄𝑅 = 𝐷ℎ𝐷 + 𝐵ℎ𝐵

𝑄𝐶 = 𝐷ℎ𝐷 + 𝐵ℎ𝐵 − 𝑄𝑅− 𝐹ℎ𝐹

Right side of the equation:

𝑘𝑚𝑜𝑙 𝑘𝑚𝑜𝑙 𝑘𝑗
𝐹 = 54.968 = 0.01526890 , ℎ𝐹 = −239764.27
ℎ𝑟 𝑠 𝑘𝑚𝑜𝑙

𝑄𝐹 = 𝐹ℎ𝐹 = −3660.935614 KW

Left side of the equation:

𝑘𝑚𝑜𝑙 𝑘𝑚𝑜𝑙 𝑘𝑗
𝐷 = 1.5293 = 0.000424817 , ℎ𝐷 = −86489 ∗ 104
ℎ𝑟 𝑠 𝑘𝑚𝑜𝑙

𝑄𝐷 = 𝐷ℎ𝐷 = −36.74178837 KW

𝑘𝑚𝑜𝑙 𝑘𝑚𝑜𝑙 𝑘𝑗
𝐵 = 53.4387 = 0.014844078 , ℎ𝐵 = −199584.46
ℎ𝑟 𝑠 𝑘𝑚𝑜𝑙

𝑄𝐵 = 𝐵ℎ𝐵 = −2962.647389 KW

𝐷ℎ𝐷 + 𝐵ℎ𝐵 = −3 ∗ 103 𝐾𝑊

𝑄𝐹 = 𝐹ℎ𝐹 = −3660.935614 KW

𝑄𝑅 = 6.73 ∗ 102 KW

Solving equation

𝑄𝐶 = 𝐷ℎ𝐷 + 𝐵ℎ𝐵 − 𝑄𝑅− 𝐹ℎ𝐹

𝑄𝐶 = −17.8536 KW
45

4.4 COMPRESSOR (C-101) ENERGY BALANCE

Figure 4-4: Compressor (C-101)

Qͦ -Wͦ = ∆Hͦ +∆𝐸𝑘 +∆𝐸𝑝

ASSUMPTION
1-Adiabatic (Qͦ=0)
2- No vertical displacement (∆𝐸𝑝 =0)
3- The system is stationary (∆𝐸𝑘 =0)

mͦ =106.9 ℎ , 𝑐𝑝4 at (𝑇4 =25c) =1.574

𝐾𝑔 𝐾𝐽 𝐾𝐽 𝐾𝐽
, 𝑐𝑝5 at (𝑇5 =151.3c) =1.961 𝐾𝑔.𝑐 , 𝑐𝑝 = 1.7675 𝐾𝑔.𝑐 from
𝐾𝑔.𝑐

HYSYS.

Calculation of work:
𝑝2 𝑎
−1
Theoretical reversible adiabatic power = mͦ𝑍1 R𝑇1
𝑝1
𝑎
(𝐾−1)
Where 𝑇1 is inlet temperature, R = Gas Constant, 𝑍1 =compressibility, m = molar flow rate, a =
𝐾
(1.21−1)
= =0.174
1.21
𝑝2 𝑎
−1
Work = (mͦ𝑍1 R𝑇1
𝑝1
𝑎
)/efficiency
50.174
−1
=0.0297*0.99145 ∗8.314*298* 1
0.174

=135.505/0.75 =180.67KW
46

4.5 COMPRESSOR (C-102) ENERGY BALANCE

Figure 4-5: Compressor (C-102)

Qͦ -Wͦ = ∆Hͦ +∆𝐸𝑘 +∆𝐸𝑝

ASSUMPTION
1-Adiabatic (Qͦ=0)
2- No vertical displacement (∆𝐸𝑝 =0)
3- The system is stationary (∆𝐸𝑘 =0)

mͦ =48.51 ℎ , 𝑐𝑝4 at (𝑇4 =56.67c) =1.736

𝐾𝑔 𝐾𝐽 𝐾𝐽
, 𝑐𝑝5 at (𝑇5 =143.5c) =2.075 ,
𝐾𝑔.𝑐 𝐾𝑔.𝑐

𝐾𝐽
𝑐𝑝 = 1.9055 𝐾𝑔.𝑐 .

Calculation of work:
𝑝2 𝑎
−1
Theoretical reversible adiabatic power = mͦ𝑍1 R𝑇1
𝑝1
where 𝑇1 is inlet temperature, R = Gas Constant,
𝑎
(𝐾−1) (1.134−1)
𝑍1 = compressibility, m = molar flow rate, a = = =0.1182
𝐾 1.134
𝑝2 𝑎
−1
Work = (mͦ𝑍1 R𝑇1
𝑝1
𝑎
)/efficiency
50.1182
−1
=0.0135*0.977 ∗8.314*338.67* 1
0.1182

=65.8344/0.75 =87.779KW
47

4.6 PUMP (P-101) ENERGY BALANCE

Figure 4-6: Pump (P-101)

Given:

Mass flow =3107 kg/h, Efficiency𝜀 = 0.75, density of liquid=594.1𝑘𝑔/𝑚3 , 𝑃1 = 100𝐾𝑝𝑎, 𝑃2 =

500𝐾𝑝𝑎. ∆𝑃 = 500 − 100 = 400𝑘𝑝𝑎 = 4𝑏𝑎𝑟

Calculating the pump power:

𝑚3
∆𝑃(𝑏𝑎𝑟) ∗ 𝑓𝑙𝑜𝑤(min)
𝑃𝑜𝑤𝑒𝑟(𝐾𝑊) = 1.67 ∗
𝜀

Volumetric flowrate = (3107)/(60)/(594.1) = 0.08716 m3/min

𝑚3
4 ∗ 0.08716 (min)
𝑃𝑜𝑤𝑒𝑟(𝐾𝑊) = 1.67 ∗ = 0.7763𝐾𝑊
0.75
48

4.7 HEATER (E-101) ENERGY BALANCE

Figure 4-7: Heater (E-101)

Qͦ -Wͦ = ∆Hͦ +∆𝐸𝑘 +∆𝐸𝑝

ASSUMPTION:

1. The energy is not transferred across the boundary by a moving part.

(e.g., Piston, impeller, rotor), then Ws = 0.

2. The inflow and outflow streams are of the same velocity, then 𝛥EK=0.

3. There is no large vertical distance between the inlets and outlets of a system, then 𝛥Ep =0

4. Then the equation becomes: ∆𝑯=Q

Calculation of heat flow Q:

Temperature changes, there is phase change, calculating the heat duty:

𝐻𝑖𝑛 = −1.593 ∗ 105 𝐾𝑗⁄𝐾𝑔𝑚𝑜𝑙𝑒 𝐻𝑢𝑡 = −1.139 ∗ 105 𝐾𝑗⁄𝐾𝑔𝑚𝑜𝑙𝑒

𝑚 = 53.4 𝑘𝑔𝑚𝑜𝑙𝑒/ℎ𝑟

𝐐 = ∆𝑯

𝑲𝑱
𝑸( ) = 𝒎 ∗ (𝑯𝒐𝒖𝒕 − 𝑯𝒊𝒏 )
𝒉𝒓
49

𝑘𝑗 𝑘𝑔𝑚𝑜𝑙
𝑄( ) = 53,45 ∗ (−1.139 ∗ 105 + 1.593 ∗ 105 )𝐾𝑗/𝐾𝑔𝑚𝑜𝑙𝑒
ℎ𝑟 ℎ𝑟

𝑄 =674.1 KW

4.8 HEATER (E-102) ENERGY BALANCE

Figure 4-8: Heater (E-102)

Qͦ -Wͦ = ∆Hͦ +∆𝐸𝑘 +∆𝐸𝑝

ASSUMPTION:

1. The energy is not transferred across the boundary by a moving part.

(e.g., Piston, impeller, rotor), then Ws = 0.
2. The inflow and outflow streams are of the same velocity, then 𝛥EK=0.
3. There is no large vertical distance between the inlets and outlets of a system, then 𝛥Ep
=0
4. Then the equation becomes: ∆𝑯=Q

Calculation of heat flow Q:

Temperature changes, there is no phase change, calculating the heat duty:

𝑇𝑖𝑛 = 151.3𝐶° 𝑇𝑜𝑢𝑡 = 200𝐶°

50

𝑚 = 106.9 𝑘𝑔𝑚𝑜𝑙𝑒/ℎ𝑟

𝑘𝑗
𝐶𝑝 = 57.115
𝑘𝑔𝑚𝑜𝑙𝑒. 𝐶°

𝐐 = ∆𝑯

𝑲𝑱
𝑸( ) = 𝒎 ∗ 𝑪𝒑 ∗ (𝑻𝒐𝒖𝒕 − 𝑻𝒊𝒏 )
𝒉𝒓

𝑘𝑗 𝑘𝑔𝑚𝑜𝑙 𝑘𝑗
𝑄( ) = 106.9 ∗ 57.115 (200 − 151.13)𝐶°
ℎ𝑟 ℎ𝑟 𝑘𝑔𝑚𝑜𝑙𝑒. 𝐶°

𝑄 = 82.88𝐾𝑊

4.9 HEATER ( E-105) ENERGY BALANCE

Figure 4-9: Heater (E-105)

Qͦ -Wͦ = ∆Hͦ +∆𝐸𝑘 +∆𝐸𝑝

ASSUMPTION:

1. The energy is not transferred across the boundary by a moving part.

(e.g., Piston, impeller, rotor), then Ws = 0.
2. The inflow and outflow streams are of the same velocity, then 𝛥EK=0.
3. There is no large vertical distance between the inlets and outlets of a system, then 𝛥Ep
=0
4. Then the equation becomes: ∆𝑯=Q
51

• Calculation of heat flow Q :

• Temperature changes , there is phase change, calculating the heat duty:

𝐻𝑖𝑛 =-86488.4𝐾𝑗⁄𝐾𝑔𝑚𝑜𝑙𝑒 𝐻𝑜𝑢𝑡 =-47399.3𝐾𝑗⁄𝐾𝑔𝑚𝑜𝑙𝑒

𝑚 = 1.529 𝑘𝑔𝑚𝑜𝑙𝑒/ℎ𝑟

𝐐 = ∆𝑯

𝑲𝑱
𝑸( ) = 𝒎 ∗ (𝑯𝒐𝒖𝒕 − 𝑯𝒊𝒏 )
𝒉𝒓

𝑘𝑗 𝑘𝑔𝑚𝑜𝑙
𝑄( ) = 1.529 ∗ (−47399.3 + 86488.4)𝐾𝑗/𝐾𝑔𝑚𝑜𝑙𝑒
ℎ𝑟 ℎ𝑟

𝑄 =16.602 KW
52

4.10 HEATER (E-106) ENERGY BALANCE

Figure 4-10: Heater (E-106)

Qͦ -Wͦ = ∆Hͦ +∆𝐸𝑘 +∆𝐸𝑝

ASSUMPTION:

1. The energy is not transferred across the boundary by a moving part.

(e.g., Piston, impeller, rotor), then Ws = 0.
2. The inflow and outflow streams are of the same velocity, then 𝛥EK=0.
3. There is no large vertical distance between the inlets and outlets of a system, then 𝛥Ep
=0
4. Then the equation becomes: ∆𝑯=Q

• Calculation of heat flow Q :

• Temperature changes , there is no phase change, calculating the heat duty:

𝑇𝑖𝑛 = 143.5𝐶° 𝑇𝑜𝑢𝑡 = 200𝐶°

𝑚 = 48.51 𝑘𝑔𝑚𝑜𝑙𝑒/ℎ𝑟

𝑘𝑗
𝐶𝑝 = 87.005
𝑘𝑔𝑚𝑜𝑙𝑒. 𝐶°

𝐐 = ∆𝑯

𝑲𝑱
𝑸( ) = 𝒎 ∗ 𝑪𝒑 ∗ (𝑻𝒐𝒖𝒕 − 𝑻𝒊𝒏 )
𝒉𝒓
53

𝑘𝑗 𝑘𝑔𝑚𝑜𝑙 𝑘𝑗
𝑄( ) = 48.51 ∗ 87.005 (200 − 143.5)𝐶°
ℎ𝑟 ℎ𝑟 𝑘𝑔𝑚𝑜𝑙𝑒. 𝐶°

𝑄 =66.24 KW

4.11 COOLER (E-103) ENERGY BALANCE:

Figure 4-11: Cooler (E-103)

Qͦ -Wͦ = ∆Hͦ +∆𝐸𝑘 +∆𝐸𝑝

ASSUMPTION:
1. The energy is not transferred across the boundary by a moving part.
2. (e.g., Piston, impeller, rotor), then Ws = 0.
3. The inflow and outflow streams are of the same velocity, then 𝛥EK=0.
4. There is no large vertical distance between the inlets and outlets of a system, then 𝛥Ep
=0
5. Then the equation becomes: 𝑄= Qc

Calculation of heat flow Q:

Temperature changes, phase change, latent heat can’t be neglected and calculate heat duty:
𝑇𝑖𝑛 = 196.1𝐶° 𝑇𝑜𝑡 = 56.67𝐶°

𝑛 = 103.5 𝑘𝑚𝑜𝑙/ℎ𝑟
54

𝑘𝑗
𝑚𝑜𝑙𝑎𝑟 𝑒𝑛𝑡ℎ𝑎𝑙𝑝𝑦 = 43090 ∗ 𝑓𝑟𝑜𝑚 𝐻𝑌𝑆𝑌𝑆
𝑘𝑚𝑜𝑙
𝑘𝑗
𝑄𝑐 (ℎ𝑟) = 𝑛 × 𝑚𝑜𝑙𝑎𝑟 𝑒𝑛𝑡ℎ𝑎𝑙𝑝𝑦 =103.5* 43090 = 4459815

Q =1238.84KW

4.12 COOLER (E-104) ENERGY BALANCE:

Figure 4-12: Cooler (E-104)

Qͦ -Wͦ = ∆Hͦ +∆𝐸𝑘 +∆𝐸𝑝

ASSUMPTION:
1. The energy is not transferred across the boundary by a moving part.
2. (e.g., Piston, impeller, rotor), then Ws = 0.
3. The inflow and outflow streams are of the same velocity, then 𝛥EK=0.
4. There is no large vertical distance between the inlets and outlets of a system, then 𝛥Ep
=0
5. Then the equation becomes: ∆𝑯=Q

Calculation of heat flow Q:

Temperature changes only, no phase change, latent heat can be neglected and calculate heat duty:
𝑇𝑖𝑛 = 56.67𝐶° 𝑇𝑜𝑢𝑡 = 44.86𝐶°

𝑚 = 6176𝑘𝑔/ℎ𝑟
55

𝑘𝑗
𝐶𝑝 = 2.2495
𝑘𝑔. 𝐶°

𝐐 = ∆𝑯

𝑲𝑱
𝑸( ) = 𝒎 ∗ 𝑪𝒑 ∗ (𝑻𝒐𝒖𝒕 − 𝑻𝒊𝒏 )
𝒉𝒓

𝑘𝑗 𝑘𝑗
𝑄( ) = 6176 ∗ 2.2495 (44.86 − 56.67)𝐶°
ℎ𝑟 𝑘𝑔. 𝐶°

𝑄 =45.6537KW
56

4.13 RESULT OF ENERGY BALANCE:

Error between Scaled Hand Calculation and HYSYS Calculation

Table 4-5: Difference between scaled hand calculations and HYSYS calculation

Error between
Equipment By Hand By HYSYS Hand and HYSYS
%

P-101 Power (KW) 0.7763 0.7746 0.219468

C-101 Work (KW) 180.67 181.6 0.51211

0.014837
E-101 Q (KW) 674.1 674

0.379476
E-102 Q (KW) 82.88 82.57

0.37994
R-101 Q (KW) -2622 -2632

0.01312
E-103 Q (KW) 1238.84 1239

66.24 65.02 1.876346

E-106 Q (KW)

C-102 Work (KW) 87.779 85.79 2.318452

45.65 45.59 0.139619

E-104 Q (KW)

E-105 Q (KW) 16.602 16.61 0.04811

Q-Reboiler QR (KW) 673 679.4 0.94201

Q-Condenser QC (KW) -17.8536 -17.86 0.03583

57

5 CHAPTER 5: EQUIPMENT DESIGN

It has been clarified into greater detail regarding the design of the machinery needed to perform
the duties of these process units, or unit activities, through the process flow diagram of production
of n-octane, the n-octane production process went through many uints. A design for these units
will be presented in this chapter (Heat exchangers, Reactor, Tower, Flash drum, Pump and
compressors).

5.1 DESIGN OF REACTOR(R-101):

Production of n-octane is produced from iso-butane and ethylene according to the following
equation:

2C2H4 (ethylene) +C4H10 (i-butane) →C8H18 (n-octane)

The type of reactor used is packed bed catalytic reactor, which is treated as a heat exchanger shell
and tube to maintain iso thermal , cold water was chosen to cool the reactor (this reaction is
exothermic reaction ) , catalyst used that suits the operational conditions of the reactor is zeolite .
x
dx
Wcatalyst = Fi−butane ∫
−ri−butane
0

Using the Aspen Hysys software, it is possible to find the appropriate size that achieves the desired
conversion of iso-butane (88.12%), while maintaining the operational conditions of the reactor.

Table 5-1 Reactor Variables and design summary table

Parameter Value Units

Temperature 200 Cͦ
Pressure 500 Kpa
Orientation Vertical
MOC C.S.
Volume 2.75 𝑚3
Length of tube 4.18 m
58

Number of tubes 50 tube

Diameter of the shell 1.148 m
Weight of catalyst 4675 Kg
• The weight of catalyst obtained by this equation :

Wcatalyst = Vr ∗ ρbulk

Kg
= 2.75m3 *1700m3 = 4675Kg

Table 5-2 Physical properties for process stream

Property Inlet Mean outlet

T(Cͦ) 200 200 200
𝑐𝑝 (Kj/Kg. Cͦ) 2.29 2.37 2.45
Thermal conductivity(W/m. Cͦ) 0.039 0.033 0.0288
3
Density (Kg/𝑚 ) 5.01 8.92 12.84
Viscosity (mN.s/𝑚 2 ) 0.015 0.012 0.0104
Table 5-3 Physical properties for utility stream

Property Inlet Mean outlet

T(Cͦ) 30 37.5 45
𝑐𝑝 (Kj/Kg. Cͦ) 4.13 4.17 4.2
Thermal conductivity(W/m. Cͦ) 0.613 0.622 0.631
3
Density (Kg/𝑚 ) 989 982 974
Viscosity (mN.s/𝑚 2 ) 0.82 0.72 0.61

• The mass of cooling water is found by :

Q = m ∗ cp ∗ (Tout − Tin )

Q
m=
cp ∗ (Tout − Tin )

2621.47
m= = 41.9Kg/s
4.17 ∗ (45 − 30)
59

• The Log-mean temperature difference (LMTD) is calculated by this way , because the
reactor is under iso thermal conditions, there is no difference in choosing counter or co -
current :
∆T1 = 200 − 45 = 155 Cͦ
∆T2 = 200 − 30 = 170Cͦ

∆T2 − ∆T1 170 − 155

∆TLMTD = = = 162.3Cͦ
∆T 170
In (∆T2 ) In ( )
1 155

• Assume an initial value of (U ) Through table 12.1 in the book (Chemical Engineering
volume 6 ) in this reactor organic solvents as hot fluid and water as cold fluid U=250
(W/(m2 ∗ K)) [1]
• Calculating the area of heat transfer from equation :
Q 2621.47 ∗ 103
A= = = 65 m2
U ∗ LMTD 250 ∗ 162.3
Tube SIDE CALCULATION

Table 5-4 Default dimensions of the tube

Tube outer diameter (m) 0.1

Tube inner diameter(m) 0.094

Tube length(m) 4.18

Pitch/dia𝑝𝑡 1.25 (Triangular)

• Area of single tube :

Asingle tube = π ∗ Dout ∗ L = π ∗ 100 ∗ 10−3 ∗ 4.18 = 1.31m2

• The number of tubes inside this reactor is calculated by dividing the total area by the area
of single tube :
60

total area 65
Ntubes = = = 50 tubes
area of single tube 1.31

• For one passe, tubes per pass same number of tubes (50 tubes).

• Tube cross-sectional area :

π
= 4 ∗ (inert diameter)2

π
= 4 ∗ (0.094)2= 0.0069m2

• Area per pass same :

= 0.0069*50 =0.34 m2

Tube side heat transfer coefficient :

• Volumetric flowrate
m 2
inlet
= density = 8.9 = 0.224 m3 /s

• Tube side velocity

voulmetric flow 0.224
= = = 0.65 m/s
area per pass 0.34

• Reynold’s number:
utube ∗din ∗ρ
Re = μ

0.65 ∗ 0.094 ∗ 8.9

Re = = 42,841
0.0126 ∗ 10−3

• Prandtl number:
cp ∗ μ 2.37 ∗ 103 ∗ 0.012 ∗ 10−3
𝑃r = = = 0.88
k 0.033
• Nusselts number :
= jh ∗ Re ∗ Pr 0.33
61

jh = 0.0185
• Value 𝑗ℎ from Figure 12.23 tube -side heat -transfer factor 1 in the book (Chemical
Engineering volume 6 )[2]
= jh ∗ Re ∗ Pr 0.33

=0.0185*42,841 ∗ 0.880.33=762.65

• Heat transfer coefficient :

Nu∗k 762.65∗0.033 W
ht = = =275.6C∗m2
din 0.094

Shell side calculations :

• The bundle diameter (𝐷𝑏𝑢𝑛𝑑𝑙𝑒 ):
Ntubes 1
Dbundle = dout ∗ ( )N1
K1
50 1
Dbundle = 100 ∗ ( )2.142 = 1.06 m
0.319
• Shell diameter :
(Was used pull-through floating head tubes)
Shell clearance = 90 mm from figure above [3]
Shell diameter:
= bundle diameter + shell clearance = 1060+ 100 =1160 mm [1.16m]
Shell side heat transfer coefficient :
Baffle spacing:
𝐷𝑠ℎ𝑒𝑙𝑙 1.16
= = = 0.232𝑚
5 5
• Area of cross-flow for the hypothetical row of tubes at the shell equator :
pt = 1.25 ∗ dout = 1.25 ∗ 100 = 125m
(pt − dout )
Ashell = ∗ Ds ∗ baffle spacing
pt
(125 − 100)
Ashell = ∗ 1.16 ∗ 0.232 = 0.053m2
125
62

• Equivalent diameter (hydraulic diameter) For an equilateral triangular pitch arrangement:

1.1
𝐷𝑒 = ( ) ∗ 𝑝𝑡 2 − 0.917 ∗ 𝑑𝑜 2 = 0.071𝑚
𝑑𝑜

• Volumetric flowrate
m 41.9
inlet
= density = 981.7 = 0.0426m3 /s

• Shell side velocity

𝑣𝑜𝑢𝑙𝑚𝑒𝑡𝑟𝑖𝑐 𝑓𝑙𝑜𝑤 0.0426
= = = 0.808 𝑚/𝑠
𝐴𝑠ℎ𝑒𝑙𝑙 0.053

• Reynold’s number:

ushell ∗ de ∗ ρ
Re =
μ

0.808 ∗ 0.071 ∗ 981.7

Re = = 78762.45
0.715 ∗ 10−3

• Prandtl number:
cp ∗ μ 4.17 ∗ 103 ∗ 0.715 ∗ 10−3
Pr = = = 4.79
k 0.622

• Nusselts number :
= jh ∗ Re ∗ Pr 0.33
jh = 0.0025
• Value 𝑗ℎ from Figure 12.29 shell -side heat -transfer factor ,segmental baffles (25%) in
the book (Chemical Engineering volume 6 )[2]
= jh ∗ Re ∗ Pr 0.33

= 0.0025*78762.45 ∗ 4.790.33=330.28
63

• Heat transfer coefficient :

Nu∗k 330.28∗0.622 W
hs = = =2895.65C∗m2
de 0.071

• The fouling factors:

• For the process side (tube) 0.0002 𝑚2 . 𝑘/𝑤 and utility (shell) side 0.0013 𝑚2 . 𝑘/𝑤 .
• The overall heat transfer coefficient , using carbon steel K =0.55 :
1 1 1 do − di
= + +
U hs ht 1000 ∗ k
1 1 1 100−94
= 2895.65 + 275.6 + 1000∗55 = 0.00408
U

U = 244.9 w/ m2 . c
Urequired − Uestimated
error% =
Urequired

250−244.9
error% = = 2%
250
64

5.2 DESIGN OF DISTILLATION (T-101):

A distillation column is a commonly employed device in chemical industries for separating
components within a mixture. It operates on the principle of exploiting the differing volatilities of
components to separate them according to their boiling points. Designing such a column can be
intricate, requiring a blend of theoretical computations, practical correlations, and engineering
expertise.

Figure 5-1 Distillation column (T-101)

Designing a distillation column is achieved by the following steps applied on (T-101):

• Step 1: Obtain the composition in the feed, the bottom, and the top of the distillation
column from mass balance.
65

• Step 2: Choose the light key component (LK) and the heavy key component (HK) based
on the boiling point, then obtain K value for (LK) and (HK) in the top and the bottom, then
calculate the relative volatility for the top and the bottom.

𝐾(𝐿𝑘)
𝛼 𝑡𝑜𝑝 𝑜𝑟 𝑏𝑜𝑡𝑡𝑜𝑚 =
𝐾(𝐻𝑘)

8.024
𝛼𝑡𝑜𝑝 = = 8.03
0.9993

0.0657
𝛼𝑏𝑜𝑡𝑡𝑜𝑚 = = 1072.8
6.1 ∗ 10−5

Where:

K(LK): The vapor liquid-equilibrium constant for the light key components.

K(HK): The vapor liquid-equilibrium constant for the heavy key components.

• Step 3: Calculate the average relative volatility by the geometric mean of the relative
volatility at the top and the bottom of the column.

2
𝛼 𝑎𝑣𝑔 = √ 𝛼𝐿,𝐷 ∗ 𝛼𝐿,𝐵

2
𝛼𝑎𝑣𝑔 = √8.03 ∗ 1072.8 = 92.814

• Step 4: Determine the minimum reflux ratio in multicomponent distillations.

Rmin =0.3

• Step 5: determine the minimum number of theoretical stages using The Fenske equation.
66

𝑥 𝑥
log ((𝑥 𝐿𝐷 ) ∗ ( 𝑥𝐻𝐵 ))
𝐻𝐷 𝐿𝐵
𝑁𝑚𝑖𝑛 =
log(𝛼𝐿,𝑎𝑣𝑔 )

0.6194 0.9999
log ((0.0001) ∗ (0.0001))
𝑁𝑚𝑖𝑛 = = 3.96
log 92.814

Where:

Nmin: The minimum number of stages

: The mole fraction of the light key component in the distillate.

: The mole fraction of the heavy key component in the distillate.

: The mole fraction of the heavy key component in the bottom.

: The mole fraction of the light key component in the bottom.

𝛼𝑎𝑣𝑔: The average relative volatility of the light key.

• Step 6: Calculate the actual number of stages by Gilliland equation.

𝑁 − 𝑁𝑚𝑖𝑛 𝑅 − 𝑅𝑚𝑖𝑛
=
𝑁+2 𝑅+1

𝑁 − 3.96 0.9 − 0.3

=
𝑁+2 0.9 + 1

N=6.71

Where:

Nmin: Minimum number of stages.

N: Actual number of stages.

67

R: Reflux ratio.

Rmin: Minimum Reflux ratio

• Step 7: Determine the feed-point location by an alternative approach, which is to use the
empirical equation given by Kirkbride.
2
Nr 𝐵 𝑥 𝑥
Log [ ] = 0.206 Log [( ) ( 𝑓,𝐻𝐾 ) ( 𝑏 ,𝐿𝐾 ) ]
Ns D 𝑥𝑓,𝐿𝐾 𝑥𝑏,𝐻𝐾

Nr 53.43 0.9721 0.0001 2

Log [ ] = 0.206 Log [( )( )( ) ]
Ns 1.5 0.0173 0.999

Nr
[ ] = 5.6028
Ns

Ntheortical = Nr + N𝑠

Nr + N𝑠=6

Nr=5.091 (feed point)

Ns=0.908

Where:

Nr: Number of stages above the feed, including any partial condenser.

Ns: Number of stages below the feed, including the reboiler.

B: Molar flow bottom product.

D: Molar flow top product.

𝑥F, HK: Mole fraction of the heavy key in the feed.

𝑥F, LK: Mole fraction of the light key in the feed.

𝑥B, LK: Mole fraction of the light key if in the bottom product.

𝑥D, HK: Mole fraction of the heavy key in the top product.
68

Step 8: Determine the column diameter.

The diameter of a tray column is mainly based on tray spacing, and the vapor load inside the
column and the velocity of vapor.

The actual velocity of vapor inside the column can be estimated by estimated by Fair’s correlation:

2 𝜌𝑙 − 𝜌𝑣
𝑢𝑎𝑐𝑡 = 𝐹𝑓 × uma𝑥 = 𝐹𝑆𝑇 ∗ 𝑐𝑓 ∗ √
𝜌𝑣

2 593.5−8.216
𝑢𝑎𝑐𝑡 rectifing = 0.9213 ∗ 0.38 ∗ √ 8.216
=2.956

2 535.9 − 17.47
𝑢𝑎𝑐𝑡 stripping = 0.794 ∗ 0.0403 ∗ √ = 0.1746
17.74

Where:

Ff: is the flooding capacity factor.

𝐹𝑆𝑇: is the surface tension factor.

Cf: is the flooding capacity factor of Fair.

𝐹𝑆𝑇 can be calculated by:

𝜎 0.2
𝐹𝑆𝑇 = ( )
0.02

13.28 0.2
𝐹𝑆𝑇 ,𝑟ectifyin𝑔 =( ) = 0.921
0.02

6.343 0.2
𝐹𝑆𝑇 ,𝑠𝑡𝑟𝑖𝑝𝑝𝑖𝑛𝑔 =( ) = 0.7947
0.02
69

Where: is the liquid surface tension in N/m.

The flooding capacity factor 𝐶𝑓 can be calculated from:

𝑙𝑜𝑔10 𝐶𝑓 = −0.94506 − 0.70234𝑙𝑜𝑔10 ∗ 𝐹𝐿𝑉 − .022618(𝑙𝑜𝑔10 ∗ 𝐹𝐿𝑉 )2

For rectifying

𝑙𝑜𝑔10 𝐶𝑓 = −0.94506 − 0.70234𝑙𝑜𝑔10 ∗ 0.0557 − .022618(𝑙𝑜𝑔10 ∗ 0.0557)2

𝐶𝑓 , rectifying = 0.38

For stripping

𝑙𝑜𝑔10 𝐶𝑓 = −0.94506 − 0.70234𝑙𝑜𝑔10 ∗ 3.5 − .022618(𝑙𝑜𝑔10 ∗ 3.5)2

𝐶𝑓 , stripping = 0.0403

Where:

FLV: the flow parameter

FLV is the flow parameter which can be calculated from:

𝐿 𝜌𝑣
𝐹𝐿𝑉 = ∗√
𝑣 𝜌𝐿

1.376 8.216
𝐹𝐿𝑉 ,𝑟𝑒𝑐𝑡𝑖𝑓𝑖𝑛𝑔 = ∗ √593.5 =0.0557
2.91

56.344 17.47
𝐹𝐿𝑉 ,𝑠𝑡𝑟𝑖𝑝𝑖𝑛𝑔 = ∗ √535.9 =3.5
2.91

Where: L and V are the flow rates of liquid and vapor inside the column respectively.
70

It is calculated at two points, one in the stripping section and the other in the rectifying section.
According to the continuity equation

4𝑣
𝐷𝑐 = √
0.9 ∗ 𝜋 ∗ 𝜌𝑣 ∗ 𝑢𝑎𝑐𝑡

4∗2.91
𝐷𝑐 , 𝑟𝑒𝑐𝑡𝑖𝑓𝑖𝑛𝑔 = √0.9∗𝜋∗8.216∗2.956 =0.41

4∗2.91
𝐷𝑐 , 𝑠𝑡𝑟𝑖𝑝𝑝𝑖𝑛𝑔 = √0.9∗𝜋∗17.47∗0.1747 =1.16

• Step 9: Determine the column height.

Height = (number of trays − reboiler or condenser)(TS) + 1.2 + 1.8

Height = (7 − 0)(0.6) + 1.2 + 1.8 = 7 m

• Step 10: Determine the tray specifications.

A number of empirical equations are used to determine certain areas in tray design:

π
𝐴𝐶 = Dc 2
4
π
𝐴𝐶 = (1.53)2 = 2.359
4

𝐴𝑑 = 0.12𝐴𝐶

𝐴𝑑 = 0.12 ∗ 2.359 = 0.283

𝐴𝑛 = 𝐴𝐶 − 𝐴𝑑

𝐴𝑛 = 2.359 − 0.283 = 2.0767

71

𝐴𝑎 = 𝐴𝐶 − 2𝐴𝑑

𝐴𝑎 = 2.359 − 2 ∗ 0.283 = 1.793

𝐴ℎ = 0.1𝐴𝑎

𝐴ℎ = 0.1 ∗ 1.793 = 0.1793

Where:

𝐴𝐶 is the total column cross-sectional area.

𝐴𝑑 is the cross-sectional area of downcomer.
𝐴𝑛 is the net area available for vapor-liquid disengagement.
𝐴𝑎 is the active area for single pass trays.
𝐴ℎ is the total area of all active holes.
𝐴𝑑 0.283
∗ 100% = ∗ 100% = 11.99%
𝐴𝐶 2.359

From Figure 11.31 vol.6 obtain 𝐿w/𝐷c, where 𝐿w is the length of the weir and 𝐷𝐶 is the
diameter of the column:
𝐿𝑊
= 0.75
𝐷𝐶

Then, calculate the weir length from the following equation:

𝐿𝑊
𝐿𝑊 = ∗ 𝐷𝐶
𝐷𝐶

𝐿𝑊 = 0.75 ∗ 1.53 = 1.3

Where: 𝑙𝑤 is the weir length. Plate thickness and hole size:

Plate thickness has standard values based on the material used to construct the plate, for carbon
steel, typical plates of 5 mm thickness are used, for stainless steel a thickness of 3 mm is common.

Hole sizes usually vary from 2.5 to 12 mm, where 5 or 6 mm is a preferred size.
72

Check weeping:

Weeping refers to the lower limit of the operating range where vapor flow is so slow that it cannot
hold the liquid from leaking through the holes. As entrainment, weeping is not desirable since it
lowers the efficiency of the plate.

𝐾2 is a constant that can be obtained from figure 11.30, after calculating (hw+how) to calculate
the minimum vapor velocity.

1.7115 2
ℎ𝑜𝑤 𝑚𝑎𝑥 = 750 𝑥 ( )3 = 15.22
1.3 ∗ 681.3

1.2 2
ℎ𝑜𝑤 𝑚𝑖𝑛 = 750 𝑥 ( )3 = 12.7569
1.3 ∗ 681.3

ℎ𝑜𝑤 = ℎ𝑜𝑤 𝑚𝑎𝑥 + ℎ𝑜𝑤 𝑚𝑖𝑛 = 27.98

𝐾2 = 28.5

The minimum vapor velocity that can hold liquid from weeping is given by:

[𝐾2 − 0.9 ∗ (25.4 − 𝑑ℎ )]

ữℎ =
𝜌𝑣 0.5

Where:

ữℎ: Is the minimum vapor velocity based on hole area in m/s.

𝑑ℎ: Is the hole diameter in mm.

[28.5 − 0.9 ∗ (25.4 − 6)]

ữℎ = = 8.867
1.550.5

• Step 11: The pressure drop is an important parameter that affects the overall efficiency of
the tray. It can be calculated using flow through orifices equations:

𝑢ℎ 2 𝜌𝑣
ℎ𝑑 = 51( )
𝐶0 𝜌𝐿

Where:

𝑢ℎ : Is the velocity of vapor through the holes in m/s.

73

𝐶0: Is the orifice correlation, and it can be obtained from Figure (5-7) below after calculating
the following parameter:

𝐴ℎ 0.1793
∗ 100% = ∗ 100% = 10
𝐴𝑎 1.793

from figure 𝐶0 assume plate thickness / hole diameter =1.2

𝐶0 = 0.88

8.867 2 1.55
ℎ𝑑 = 51( ) = 11.78 𝑚𝑚
0.88 681.3

Estimating the residual head as a function of liquid surface tension, froth density, and froth
height has been proposed. The following simple equation proposed can be used:

12.5 ∗ 103
ℎ𝑟 = = 18.347
681.3

The total plate drop is given by:

ℎ𝑡 = ℎ𝑑 + (ℎ𝑤 + ℎ𝑜𝑤 ) + ℎ𝑟 =

ℎ𝑡 = 11.78 + 27.98 + 18.347 = 58.109 𝑚𝑚

Pressure drop across trays can be calculated by:

∆𝑃𝑡 = 9.81 × 10−3 × 51.54 × 681.3 = 344.49 𝑝𝑎

𝑇ℎ𝑒 𝑐𝑜𝑙𝑢𝑚𝑛 𝑝𝑟𝑒𝑠𝑠𝑢𝑟𝑒 = 𝑝𝑝 × 𝑁𝑎𝑐𝑡𝑢𝑎=344.49 × 7= 2411.49 pa

• Step 12: Check the downcomer liquid backup

ℎ𝑎𝑝 = 27.98 − 10 = 17.98

Where: is ℎ𝑎𝑝 height of the bottom edge of the apron above the plate.

The clearance area under the downcomer is given by:

74

𝐴𝑎𝑝 = ℎ𝑎𝑝 × 10−3 𝐿𝑤

𝐴𝑎𝑝 = 17.98 × 10−3 × 0.87 = 0.01566 𝑚2

The main resistance to flow will be caused by the constriction at the downcomer outlet, and
the head loss in the downcomer can be estimated using the following equation:

𝐿𝑤𝑑 2
ℎ𝑑𝑐 = 166( )
𝜌𝐿 𝐴𝑎𝑝

2
1.715
ℎ𝑑𝑐 = 166 ( ) = ℎ𝑑𝑐 = 4.294 mm
681.3 × 0.01566

Calculate the back-up in downcomer using the following equation, and if ℎ𝑏 < 0.5 (𝑝𝑙𝑎𝑡𝑒
𝑠𝑝𝑎𝑐𝑖𝑛𝑔 + ℎ𝑤), the plate spacing is accepted.

ℎ𝑏 = ℎ𝑑𝑐 + ℎ𝑡 + ℎ𝑜𝑤 + ℎ𝑤

ℎ𝑏 = 4.294 + 58.109 + 27.98 = 90.38 𝑚𝑚

Check residence time:

ℎ𝑏 𝐴𝑑 𝜌𝐿 (90.38 + 0.1269 + 681.3) ∗ 10−3

𝜏𝑟 = = = 4.5575 𝑠
𝐿𝑚𝑎𝑥 1.7155

4.5575 > 3 , 𝑖𝑡 𝑖𝑠 𝑠𝑎𝑡𝑖𝑠𝑓𝑎𝑐𝑡𝑜𝑟𝑦.

Therefore, the spacing is acceptable since:

27.98
0.5 ∗ (0.6 + ) = 0.313
1000

0.313 < 0.5 𝑠𝑜 𝑝𝑙𝑎𝑡𝑒 𝑠𝑝𝑎𝑐𝑖𝑛𝑔 𝑖𝑠 𝑎𝑐𝑐𝑒𝑝𝑡𝑎𝑏𝑙𝑒

75

Table 5-5 Towers design summary table

Tower T-101
Temperature (℃) -41.85
Pressure (bar) 5
Orientation Vertical
MOC CS
Size
Volume (m3) 7.618
Height/Length (m) 7.2
Diameter 1.16
Internals 7 316SS sieve trays, 0.6 m tray
spacing

Figure 5-2 Distillation footprint

Figure 5-2: Distillation Footprint
76

5.3 PUMPS AND COMPRESSORS DESIGN:

Mass flow =3107 kg/h, Efficiency𝜀 = 0.75, density of liquid= 594.1𝑘𝑔/𝑚3 , 𝑃1 = 100𝐾𝑝𝑎, 𝑃2 =
500𝐾𝑝𝑎. ∆𝑃 = 500 − 100 = 400𝑘𝑝𝑎 = 4𝑏𝑎𝑟

∆p (pa)
Head (m) =
ρg

kg
400 × 103
Head (m) = m ∗ s 2 = 68.66811327 m
kg m
594.4 3 ∗ 9.8 2
m s

Calculating the pump power:

m3
∆P(bar) ∗ flow(min)
Power(KW) = 1.67 ∗
ε

Volumetric flowrate = (3107)/(60)/(594.4) = 0.087119 m3/min

m3
4 ∗ 0.087119 (min)
Power(KW) = 1.67 ∗ = 0.7759KW
0.75

Calculating the work of compressor:

γ
p2 γ−1
γ p1 −1
Work Compressor = mZ1 RT1
γ − 1 p2 a − 1
p1
a
 77

Table 5-6 Pump and compressor summary

Pumps /Compressor P-101 A/B C-101 A/B C-102 A/B

Temperature (C) -11.72 151.3 143.5

Flow (kg/h) 3107 2999 1939

Fluid Density (kg/m^3) 594.4 4.017 5.907

Power/Duty (KW) 0.7759 180.67 87.779

Inlet Pressure (bar) 1 1 1

Outlet Pressure (bar) 5 5 5

Efficiency 75% 75% 75%

Type/Drive Centrifugal /Electric Centrifugal /Electric Centrifugal /Electric

78

5.4 DESIGN OF FLASH DRUM:

Figure 5-3 Flash Drum

Uperm = 0.07√((𝝆𝒍 − 𝝆𝒗)/𝝆𝒗)

Uperm: settling velocity, m/s

𝑘𝑔
𝜌𝑙: 𝑙𝑖𝑞𝑢𝑖𝑑 𝑑𝑒𝑛𝑠𝑖𝑡𝑦
𝑚3
𝑘𝑔
𝜌𝑣: 𝑣𝑎𝑝𝑜𝑟 𝑑𝑒𝑛𝑠𝑖𝑡𝑦
𝑚3

If a demister pad is not used, the value of UT obtained from the previous equation should be
multiplied by a factor of 0.15 to provide a margin of safety and to allow for flow surges.

Uperm = 0.07√((671.1 − 1.472)/1.472) =1.5m/s

Ua=0.15 x 1.5= 0.225 m/s.

The most economical length to diameter ratio will depend on the operating pressure:
79

our process operating at 1 bar, so the Length-Diameter ratio (Lv/Dv) will be 3:

For preliminary designs, set the liquid height at half the vessel diameter:

𝐷𝑣
ℎ𝑣 =
2

Cross-sectional area for vapor flow:

𝜋(𝐷𝑣)2
(Av) = 0.5 ∗ = 0.393Dv2 m2
4

Vapor velocity:
𝜌𝑣
𝐴𝑣
= 0.366/0.393Dv2= 0.93Dv-2

Vapor residence time required for the droplets to settle to liquid surface:

ℎ𝑣 0.5𝐷𝑣
= = 2.2𝐷𝑣
𝑈𝑎 0.225

Actual residence time D vessel length/vapor velocity:

𝐿𝑣 3𝐷𝑣
= = 3.2 𝐷𝑣 3
𝑈𝑣 0.93(𝐷𝑣)−2

For satisfactory separation required residence time D actual.

2.2𝐷𝑣 = 3.2𝐷𝑣 3 𝐷𝑣 = 0.83𝑚 say 0.92 m (3 ft, standard pipe size)

Liquid hold-up time:

Liquid volumetric flow rate = 2.56 x 10-3

Liquid cross-sectional area:

𝜋𝐷2
D = 0.5 = 0.332m2
4

Length:
80

Lv = 3 x 0.92 = 2.76 m

Hold-up volume =2.76 x 0.332 = 0.92 m3

Hold-up time:

Liquid volume/liquid flowrate = 0.92/ 2.56 x 10-3 = 359.4 s = ~6 min

Figure 5-4 Flash drum design

Table 5-7 Vessel design summary

V-100 Vessel
56.76 Temperature, C
100 Pressure, bar
Vertical Orientation
C.s MOC
Size Unit
0.92 Volume m^3
2.76 Height/Length, m
0.92 Diameter, m
- Internals
81

5.5 Design of thermosyphon reboiler:

Figure 5-5 Thermosyphon reboiler

Vertical Thermosyphon, one by bass, the liquid which is to be boiled usually flows through the
tube side. The heating fluid usually passed through the shell side.

Exchanger duty:

Q = 674.9 KW/m2

Maximum heat flux U max = 37900W/m2

Heat transfer area required:

A = Q/U max = 674.9 x 103/37900 = 17.8 m2

Exchanger layout and piping dimensions: 𝑑◦ =30 𝑚𝑚=0.03, 𝑑𝑖 =25 𝑚𝑚=0.025 𝑚, 𝐿 =2.44 𝑚

A tube = π x Din x L = 3.14 X 0.025 X 2.44 = 0.191 m2

Number of Tubes = A/A tube = 17.8/0.191 = 92.97+~ 93 tube

V = 0.42, L = 1.26, F = 1.68

82

𝐹 1.86
ρe = 𝑉 𝐿 = 0.42 1.26 = 4.9 kg/m2
(ρ𝑉)+(ρl) (1.18)+( 703 )

The cross-sectional area of tube and bundle:

𝜋 𝜋
Ac = 4 𝐷𝑖𝑛 2 = = 4 ∗ 0.0252 = 0.0005 m2

Ab = N tube x Ac = 93 x 0.0005 = 0.0465 m2

Mass flux:

ṁ
G = 𝐴𝑏 = 1.68/ 0.0465 = 36.13 kg/m2. S

Homogenous velocity at exit:

𝐺 36.13
υH = ρe = = 7.38 m/s
4.9
ρe∗υH∗𝐷𝑖 4.9 𝑥 7.38 x 0.025
Re = = = 1807.043
µ 0.0005

From figure: jf = 0.0075

Friction pressure drop at exit:

𝐿 υH2 2.44 7.382

∆Pe= 8𝑗𝑓 𝑥 (𝐷𝑖) 𝑥 (ρe 𝑥 ) = 8 𝑥 0.0075 𝑥 (0.025) 𝑥 (4.9 𝑥 ) = 780.4985 pa/m
2 2

Homogenous velocity in liquid phase at entry:

𝐺 36.13
u L = 𝜌𝐿 = 703
= 0.051409 m/s

𝜌𝑙∗𝑢𝑙∗𝐷𝑖 703∗0.0514∗0.025
Re = = = 1771.611
µ𝑙 0.0005

Jf = 0.007

𝐿 υl2 2.44 0.05142

∆Pl = 8𝑗𝑓𝑥 (𝐷𝑖) 𝑥 (ρl x ) = 8 𝑥 0.007 𝑥 (0.025) 𝑥 (703 𝑥 ) =5.077 pa/m
2 2

Pressure drop over tube from the mean friction pressure drop:

∆Pl+∆Pe 5.077+780.49
∆P mean = == = 392.788 Pa/m
2 2
83

∆P tube = ∆P mean x L = 392.788 x 2.44 = 958.4027 Pa/m

Static pressure in tubes:

𝑔∗𝐿 𝑣𝑜
∆Ps = 𝑣𝑜−𝑣𝑖 ln ( 𝑣𝑖 ) = 598.0298 Pa

Total pressure drop:

∆P tot = ∆Ps +∆P tube = 1556.432 Pa

Available head:

Available head= g x L x ρl = 9.81 x 2.44 x 703 = 16827.29 Pa

The nucleate boiling heat transfer coefficient:

5 0.17 5 1.7
hnb = 0.104 𝑥 ((24.86)0.69) 𝑥 ((37900)0.7) 𝑥 (1.8 𝑥 ((24.86) ) + 4 𝑥 ((24.86) ) +

5 10
10 𝑥 ((24.86) ))

hnb = 2498.968 W/m2. K

Fc = 100 *from chart

Heat transfer coefficient at inlet of tube for liquid:

ρ ul Di 703∗0.0514∗0.025
Re = = = 546.14
μ 0.0005

Jh = 0.025, Pr = 2.2

ℎ𝑖 𝐷𝑖
Nu = = 𝑗ℎ 𝑋 𝑅𝑒𝑋𝑝𝑟 0.33 = 17.7
𝑘𝑓

𝑁𝑢 𝑘𝑓 17.7∗ 0.08
ℎ𝑖 = = = 56.64 W/m2. K
𝐷𝑖 0.025

Mean transfer coefficient between inlet and outlet tubes:

V 0.9
1 F ρl 0.5
=( V ) ( ) =9
Xtt 1−( F ) ρv

fc = 100
84

Rel *fc1.25 = 560232.6

from figure fs= 0.2

hcp = hi x fc + hnb x fs = 56.64 x 100 + 2498.968 8 x 0.2 = 6167.319 W/m2. K

ℎ𝑖+ℎ𝑐𝑝
h avg = = 3111.997 W/m2. K
2

Overall coefficient:

1 1 1 1 1
= havg + hsteam = 3111.997 + 8000 = 0.000446
U

U = 2240.459 W/m2. K

∆T = 25

𝑈𝑚𝑎𝑥 37900
Ureq = = = 1516 W/m2. K
∆𝑇 25

𝑈𝑟𝑒𝑞 − 𝑈
%𝑒𝑟𝑟𝑜𝑟 = = 47.8%
𝑈𝑟𝑒𝑞

So, the area available in the proposed design is more than adequate and will take care of any
fouling. But we need more iterations to reduce the error.
85

5.6 DESIGN OF HEAT EXCHANGER:

For this design we are going to use both double-pipe and shell and tube HE with the details of their
design.

5.6.1 Shell and tube heat-exchanger design:

For E-103, E-101 and E-102 since we have a large duty (larger than 500) and phase change
happened there are so many advantages for using this type of HE such as:

1- Can handle high temperature and pressure

2- High heat transfer rate efficiency
3- Can be constructed from a wide range of materials.
4- Cleaned quickly.
5- Well-established design procedures.
A shell-and-tube exchanger consists of a bundle of tubes contained in a cylindrical shell.

Figure 5-6 Shell and Tube heat-exchanger

Tube sheets can be fixed or removeable and they are used to fix the tubes and to prevent fluids
mixing.
86

Figure 5-7 Tube sheets for Shell and tube HE

Alse Shell and tube HE contains baffles and baffles are number of circular discs installed in the
shell side of the HE. And they help the tube bundle to withstand vibrations and bending. Since
25% baffle cut is the most used we going to use it for all our designs.

Figure 5-8 Baffles for shell and tube HE

Design procedure for E-101:

• Step 1: Collection of the physical properties of the cold fluid and the hot fluid that enters
the heat exchanger, for the hot fluid we are using high pressure steam. The steam will be
in the annulus side and the process stream will be in the tube side (using T1 in appendixA)
87

Table 5-8 Process stream physical properties

Tube side Inlet Mean Outlet Unit

T -11.7212 94.139423 200 C
Cp 2.141695 2.3074207 2.473146348 kJ/kg.C
thermal 9.77E-02 0.0664519 3.52E-02 W/m.C
conductivity
density 594.4081 301.02435 7.640557674 kg/m3
viscosity 0.244226 0.1282641 1.23E-02 mN.s/m2

Table 5-9 Utility Stream physical properties

Shell side Inlet Mean Outlet Unit

T 250 250 250 C
Cp 4.2876 4.63225 4.9769 kJ/kg.C
thermal 0.0453 0.32575 0.6062 W/m.C
conductivity
density 22.6365 400.6037 778.5709 kg/m3
viscosity 0.01945 0.061175 0.1029 mN.s/m2

We have heat duty of Q=674.0149 KW and and mass flow rate for the shell side equal to m =
0.86298 kg/s.

• Step 2: After gathering all the physical properties data we need to find the mass flow rate
for the tube side (cooling water):

𝑄 = 𝑚 ∗ 𝑑ℎ𝑣

Dhv = latent heat of vaporization

𝑄 674.0149 𝑘𝑔
𝑚= = = 0.405588
𝑑ℎ𝑣 1661.82 𝑠

• Step 3: We need to find the Log-mean temperature difference (LMTD). For a counter flow
heat exchanger.
88

∆𝑇2 = 250 + 11.7 = 261.72 C

∆𝑇1 = 250 − 50 = 50𝐶 C

∆𝑇2 − ∆𝑇1 261.72 − 50

∆𝑇𝐿𝑀𝑇𝐷 = = = 127.9 𝐶
∆𝑇2 261.72
𝐼𝑛 (∆𝑇 ) 𝐼𝑛 ( )
1 50

• Step 4: determining an initial Value of U, since we have organic solvents as hot fluid and
water as cold fluid we can esitamte and initial value of
U=291 (𝑊/(𝑚2 ∗ 𝐾)) (Using table T2 in appendix A)

• Step 6: Calculating the area of heat transfer from equation

𝑄 674.0149 ∗ 1000
𝐴= = = 18.98𝑚2 = 19𝑚2
𝑈 ∗ 𝐿𝑀𝑇𝐷 500 ∗ 127.9

• Step 7: Assuming the inner and outer diameter and the length of tube to calculate the area
for one tube.
We're going to use ¾ in (19.05 mm) tube OD and employ triangular tubes with a 23.81
mm pitch (pitch/dia. D 1.25)
(They the most common and widely used) from this data we can get the tube ID = 14.83
mm and length 4.88 m long (using figure C3 in appendix A)

𝑎𝑟𝑒𝑎 𝑜𝑓 𝑠𝑖𝑛𝑔𝑙𝑒 𝑡𝑢𝑏𝑒 (𝐴𝑠𝑖𝑛𝑔𝑙𝑒 𝑡𝑢𝑏𝑒 ) = 𝜋 ∗ 𝐷𝑜𝑢𝑡 ∗ 𝐿 = 𝜋 ∗ 19.05 ∗ 10−3 ∗ 4.88

= 0.292055𝑚2

• Step 8: estimating the number of tubes and the diameter bundle and area per pass:
𝑡𝑜𝑡𝑎𝑙 𝑎𝑟𝑒𝑎 19
𝑁𝑡𝑢𝑏𝑒𝑠 = = = 64 𝑡𝑢𝑏𝑒𝑠
𝑎𝑟𝑒𝑎 𝑜𝑓 𝑠𝑖𝑛𝑔𝑙𝑒 𝑡𝑢𝑏𝑒 0.292055
89

So, for 4 passes, tubes per pass N= 64/4 = 16 tubes

𝜋
Tube cross-sectional area = 4 ∗ (𝑖𝑛𝑒𝑟𝑡 𝑑𝑖𝑎𝑚𝑒𝑡𝑒𝑟)2
𝜋
∗ (14.83 ∗ 10−3 )2= 0.000173 𝑚2
4

So area per pass=0.000173*16 = 0.002764 𝑚2

Now we estimate the bundle diameter (𝐷𝑏𝑢𝑛𝑑𝑙𝑒 ):

No.passes 1 2 4 6 8
K1 0.319 0.249 0.175 0.0743 0.0365
N1 2.142 2.207 2.285 2.499 2.675

Since we proved earlier we will need 4 passes and we going to use these values for K1
and N1:
𝑁𝑡𝑢𝑏𝑒𝑠 1
𝐷𝑏𝑢𝑛𝑑𝑙𝑒 = 𝐷𝑜𝑢𝑡 ∗ ( )𝑁1
𝐾1
64 1
𝐷𝑏𝑢𝑛𝑑𝑙𝑒 = 19.05 ∗ 10−3 ∗ ( )2.285 = 0.25𝑚
0.175

• Step 9: After estimating the tube bundle from the previous equation, the shell side
diameter must be estimated, and Figure below shows the shell diameter obtained from
tubes bundle diameter. We going to use pull-through floating head tubes.
(Using figure C4 in appendix A)

Shell clearance = 88mm from figure above

Shell diameter = bundle diameter + shell clearance = 252.1264 + 88 =340 mm

We need to calculate tube side heat transfer coefficient

• Step 10: We need Reynold’s number:

90

𝑉𝑡𝑢𝑏𝑒 ∗ 𝐷𝑖𝑛 ∗ 𝑑𝑒𝑛𝑠𝑖𝑡𝑦

𝑅𝑒 =
𝑣𝑖𝑠𝑐𝑜𝑠𝑖𝑡𝑦

We need to find the velocity inside the tube:

𝑚 0,86298
𝑖𝑛𝑙𝑒𝑡
Volumetric flowrate = 𝑑𝑒𝑛𝑠𝑖𝑡𝑦 = 301.02435 = 0.002867 𝑚3 /𝑠

𝑣𝑜𝑢𝑙𝑚𝑒𝑡𝑟𝑖𝑐 𝑓𝑙𝑜𝑤 0.002687

Tube side velocity = = = 1.037306 𝑚/𝑠
𝑎𝑟𝑒𝑎 𝑝𝑒𝑟 𝑝𝑎𝑠𝑠 0.002764

1.037306 ∗ (14.83 ∗ 10−3) ∗ 301.02435

𝑅𝑒 = = 3.61 ∗ 104
0.1282641

• Step 11: Now we need to calculate prandlt number:

𝐶𝑝 ∗ 𝑢 2.307421 ∗ 10−3 ∗ 0.128264 ∗ 103
𝑃𝑟 = = = 4.45374
𝑘 0.066452

• Step 12: Considered the heat transfer factor from this Figure to calculate the Nusselt's
number. (Using figure C5 in appendix A)

L 4.88
= = 329.0627
Di 14.83 ∗ 10−3
From above figure the 𝑗ℎ = 0.0035
𝑁𝑢𝑠𝑠𝑒𝑙𝑡𝑠 𝑛𝑢𝑚𝑏𝑒𝑟 = 𝑗ℎ ∗ 𝑅𝑒 ∗ 𝑃𝑟 0.33 = 0.0036 ∗ 3.61 ∗ 104 ∗ 4.453740.33 = 212.777

• Step 13: calculating the heat transfer coefficient for the tube:
𝑁𝑢 ∗ 𝑘 212.777 ∗ 0.066452 𝑊
ℎ= = = 953.4374
𝐷𝑖𝑛 14.83 ∗ 10−3 𝐶 ∗ 𝑚2

Now we need to calculate the shell side HTC:

• Step 14: we need to calculate the area of the shell

𝐷𝑠ℎ𝑒𝑙𝑙 340
𝐵𝑎𝑓𝑓𝑙𝑒 𝑠𝑝𝑎𝑐𝑖𝑛𝑔 = = = 68.02549
5 5
91

(𝐷𝑖𝑎 − 𝐷𝑜𝑢𝑡 )
𝐴𝑠ℎ𝑒𝑙𝑙 = ∗ 𝐷𝑠 ∗ 𝑏𝑎𝑓𝑓𝑙𝑒 𝑠𝑝𝑎𝑐𝑖𝑛𝑔
𝐷𝑖𝑎
(23.81 − 19.05)
𝐴𝑠ℎ𝑒𝑙𝑙 = ∗ 340 ∗ 68.02 = 4627.467𝑚𝑚2
23.81

• Step 15: Calculate the shell-side equivalent diameter (hydraulic diameter) for an
equilateral triangular pitch arrangement.
1.1
𝐷𝑒 = ( ) ∗ 𝐷𝐼𝑎 2 − 0.917 ∗ 𝐷𝑜𝑢𝑡 2 = 13.52 𝑚𝑚
𝐷𝑖𝑎

• Step 16: the shell side velocity estimated from these equations:
𝑚𝑎𝑠𝑠 𝑓𝑙𝑜𝑤 𝑟𝑎𝑡𝑒 0.405588 𝑚3
𝑉= = = 0.001012
𝑑𝑒𝑛𝑠𝑖𝑡𝑦 400.6037 𝑠
𝑣𝑠ℎ𝑒𝑙𝑙 0.001012
Velocity in shell = = 0.21879𝑚/𝑠
𝐴𝑠ℎ𝑒𝑙𝑙 0.004627

• Step 17: Calculate Reynolds number for the shell side

𝑉𝑠ℎ𝑒𝑙𝑙 ∗ 𝐷𝑒𝑞 ∗ 𝑑𝑒𝑛𝑠𝑖𝑡𝑦 0.21879 ∗ (13.52 ∗ 10−3 ) ∗ 400.6037
𝑅𝑒 = = −3
= 1.94 ∗ 104
𝑣𝑖𝑠𝑐𝑜𝑠𝑖𝑡𝑦 0.061175 ∗ 10

• Step 18: calculate Pr:

𝐶𝑝 ∗ 𝑢
𝑃𝑟 = = 0.869924
𝑘

Now for the commonly used 25% cut. (using figure C6 in Appendix A)

𝑁𝑢𝑠𝑠𝑒𝑙𝑡𝑠 𝑛𝑢𝑚𝑏𝑒𝑟 = 𝑗ℎ ∗ 𝑅𝑒 ∗ 𝑃𝑟 0.33 = (0.0043) ∗ (1.94 ∗ 104 ) ∗ 0.860.33 = 79.58834

• Step 19: calculate the heat transfer coefficient

𝑁𝑢 ∗ 𝑘 𝑊
ℎ= = 1916
𝐷𝑒 𝐶 ∗ 𝑚2
92

• Step 20: determine the fouling factors:

For the process side (tube) 0.0002 m2.k/w and utility (shell) side 0.0013 m2.k/w

• STEP 21: calculating the overall heat transfer coefficient

Using carbon steel K =0.55
1 1 1 Dout Dout Dout
= + +( ∗ (In ( )+ ) ∗ Rfu + Rfp =282.4239
Ucalculated hshell htube 2∗k Din Din

Error%= 2% (acceptable)

• Step 22: calculating the pressure drop:

Where ∆𝑃𝑡 tube-side pressure drop, N/m2 (Pa),

𝑁𝑝 number of tube-side passes,
𝑢𝑡 tube-side velocity, m/s,
For tube side (jf=0.0031 using figure in appendix C7)
∆𝑃𝑡 = 18416.29 𝑝𝑎 = 0.18463𝑏𝑎𝑟
𝑃 = 5𝑏𝑎𝑟 𝑓𝑜𝑟 𝑡𝑢𝑏𝑒

𝑝(𝑔𝑎𝑢𝑔𝑒) = 5 − 1.01 = 3.9

0.046194
= 0.046194 < 0.1 (𝑎𝑐𝑐𝑒𝑝𝑡𝑎𝑏𝑙𝑒)
3.9
For shell side (jf = 0.04 using figure in appendix C6)

∆𝑃𝑡 = 3286𝑝𝑎 = 0.032861𝑏𝑎𝑟

𝑃 = 5𝑏𝑎𝑟 𝑓𝑜𝑟 𝑡𝑢𝑏𝑒

𝑝(𝑔𝑎𝑢𝑔𝑒) = 46.9 − 1.01 = 3.9

0.03286
= 0.000716 < 0.5 (𝑎𝑐𝑐𝑒𝑝𝑡𝑎𝑏𝑙𝑒)
3.9
93

HEAT EXCHANGER SPECIFICATION SHEET

EQUIPMENT NAME AND TYPE: Shell and tube heat exchanger (E-101)

SERVICE: Heater

FLUID PROPERTIES DATA: SHELLSIDE TUBESIDE

FLUID STATE vapor liquid
TEMPERATURE IN (OC) 250 -11.7212
TEMPERATURE OUT (OC) 250 200
DENSITY (KG/M3) 400.6037 301.0244
VISCOSITY (CP) 0.061175 0.128264
LATENT HEAT (KJ/KG) 1661.82 -
CP (KJ/KG.C) 4.63225 2.307421
THERMAL CONDUCTIVITY (W/M.C) 0.32575 0.066452
PRESSURE (BAR) 5 46.9

PROCES

S DATA: SHELLSIDE TUBESIDE

HEAT DUTY (KW) 674.0149 -
FLOW RATE (KG/S) 0.405566 0.86298
FOULING FACTOR (M2.K/W) 0,0013 0.0002
PRESSURE DROP (bar) 0.032861 0.184163
TUBE VELOCITY (M/S) - 1.383075
U ASSUMED (W/M2.K) 291 -
U CALULCATED (W/M2.K) 288.5 -
ERROR% 0.83% -

CONSTRUCTION DATA:
HEAT TRANSFER AREA (M2): 20
NUMBER OF TUBES/SHELL: 72/1
AREA OF ONE TUBE (M2): 0.292055
TUBE OUTSIDE DIAMETER (MM): 19.05
TUBE INSIDE DIAMETER (MM): 14.83
TUBE LENGTH (METER): 4.88
TUBE MATERIAL AND TYPE: Carbon steel/Pull through floating head
NUMBER OF TUBE PASSES/SHELL: 6
TUBE PITCH AND ORIENTATION: TRIANGULAR PITCH
SHELL MATERIAL: Carbon steel.
BAFFLE SPACING (MM): 77.5
AREA OF THE SHELL (M2): 0.006
Table 5-10 Specification sheet for (E-101)
94

HEAT EXCHANGER SPECIFICATION SHEET

EQUIPMENT NAME AND TYPE: Shell and tube heat exchanger (E-102)

SERVICE: Heater

FLUID PROPERTIES DATA: SHELLSIDE TUBESIDE

FLUID STATE vapor vapor
TEMPERATURE IN (OC) 250 151.3
TEMPERATURE OUT (OC) 250 200
DENSITY (KG/M3) 400.6037 3.804003
VISCOSITY (CP) 0.061175 0.15247
LATENT HEAT (KJ/KG) 1661.82 -
CP (KJ/KG.C) 4.63225 2.019037
THERMAL CONDUCTIVITY (W/M.C) 0.32575 0.038968
PRESSURE (BAR) 46.9 5

PROCESS DATA: SHELLSIDE TUBESIDE

HEAT DUTY (KW) 82.56972 -
FLOW RATE (KG/S) 0.049686 0.83304
FOULING FACTOR (M2.K/W) 0,0013 0.0002
PRESSURE DROP (bar) 1.17E-05 0.022576
TUBE VELOCITY (M/S) - 9.792669036
U ASSUMED (W/M2.K) 94.2 -
U CALULCATED (W/M2.K) 95.10 -
ERROR% 1.35% -

CONSTRUCTION DATA:
HEAT TRANSFER AREA (M2): 14
NUMBER OF TUBES/SHELL: 52/1
AREA OF ONE TUBE (M2): 0.287455728
TUBE OUTSIDE DIAMETER (MM): 50
TUBE INSIDE DIAMETER (MM): 46.8
TUBE LENGTH (METER): 1.38
TUBE MATERIA and TPYE: Carbon steel/Pull through floating bed
NUMBER OF TUBE PASSES/SHELL: 4
TUBE PITCH AND ORIENTATION: TRIANGULAR PITCH
SHELL MATERIAL: Carbon steel.
BAFFLE SPACING (MM): 139.05
AREA OF THE SHELL (M2): 0.019336
Table 5-11 Specification sheet for E-102
95

HEAT EXCHANGER SPECIFICATION SHEET

EQUIPMENT NAME AND TYPE: Shell and tube heat exchanger (E-103)

SERVICE: Cooler

FLUID PROPERTIES DATA: SHELLSIDE TUBESIDE

FLUID STATE liquid vapor
TEMPERATURE IN (OC) 30 196.87
TEMPERATURE OUT (OC) 45 56.671
DENSITY (KG/M3) 981.7855 4.075952
VISCOSITY (CP) 0.715553 0.102702
LATENT HEAT (KJ/KG) - -
CP (KJ/KG.C) 4.17071 2.264115
THERMAL CONDUCTIVITY (W/M.C) 0.622506 0.051272
PRESSURE (BAR) 4.2 1

PROCESS DATA: SHELLSIDE TUBESIDE

HEAT DUTY (KW) 1238.82 -
FLOW RATE (KG/S) 19.80191 2.25412
FOULING FACTOR (M2.K/W) 0.0002 0.0002
PRESSURE DROP (bar) - -
TUBE VELOCITY (M/S) - 10.04
U ASSUMED (W/M2.K) 129. -
U CALULCATED (W/M2.K) 127.44 -
ERROR% 1.62% -

CONSTRUCTION DATA:
HEAT TRANSFER AREA (M2): 147
NUMBER OF TUBES/SHELL: 256/1
AREA OF ONE TUBE (M2): 0.574911456
TUBE OUTSIDE DIAMETER (MM): 25
TUBE INSIDE DIAMETER (MM): 23.4
TUBE LENGTH (METER): 7.32
TUBE MATERIA and TPYE: Carbon steel/Packed bed
NUMBER OF TUBE PASSES/SHELL: 2
TUBE PITCH AND ORIENTATION: TRIANGULAR PITCH
SHELL MATERIAL: Carbon steel.
BAFFLE SPACING (MM): 123.4075666
AREA OF THE SHELL (M2): 0.015229
Table 5-12 Specification sheet for E-103
96

5.6.2 DOUBLE PIPE DESIGN PROCEDURE:

For E-104 , E-105 and E-106 we're going to use double pipe heat exchanger. A Double Pipe Heat
Exchanger, also known as a hairpin or jacketed pipe exchanger, consists of two concentric pipes.

• Design: It features an inner pipe within an outer pipe, creating an annular space for fluid
flow. The inner pipe serves as a conductive barrier for heat transfer between two fluids,
one flowing inside and the other around it.
• Operation: These exchangers can operate co-currently or counter-currently, with the latter
being more common to maximize heat exchange efficiency.
• Construction: The outer pipe is typically bare, while the inner pipe may have longitudinal
fins to increase the heat transfer surface area. The U-shape bend allows for thermal
expansion.
• Applications: Double pipe heat exchangers are versatile and used in various industries like
oil and gas, pharmaceuticals, and HVAC due to their compact design and modularity.
• Efficiency: The design is particularly beneficial for fluids with low heat transfer
coefficients, such as gases.

Figure 5-9 Double pipe HE

97

Design procedure for E-104

• Step 1: Collection of the physical properties of the cold fluid and the hot fluid that enters the heat
exchanger, for the cold fluid we are using cooling waters since it's widely used as a coolant.
The cooling water will be in the annulus side and the process stream will be in the inner
side (Using T1 in appendix A)

Table 5-13 Process side physical properties for E-104

Inner side Inlet Mean Outlet Unit

T -41.8527694 79.07362 200 C
Cp 1.361237909 1.863733 2.366227335 kJ/kg.C
thermal
conductivity 0.112350716 0.074942 0.037532696 W/m.C
density 593.4965182 301.0263 8.556010672 kg/m3
viscosity 0.233964771 0.123947 0.013928232 mN.s/m2

Table 5-14 Utility side physical properties for E-104

Annulus side Inlet Mean Outlet Unit

T 250 250 250 C
Cp 4.2876 4.63225 4.9769 kJ/kg.C
thermal
conductivity 0.0453 0.32575 0.6062 W/m.C
density 22.6365 400.6037 778.5709 kg/m3
viscosity 0.01945 0.061175 0.1029 mN.s/m2

We have Q=16.605757 KW and dhv= 1661.82 kj/kg

𝑄 = 𝑚 ∗ 𝑑ℎ𝑣

Dhv = latent heat of vaporization

𝑄 16.605757 𝑘𝑔
𝑚= = = 0.00992509
𝑑ℎ𝑣 1661.82 𝑠
98

• Step 2: We need to find the Log-mean temperature difference (LMTD). For a counter flow
heat exchanger.

∆𝑇2 = 250 + 41.8 = 291.85 C

∆𝑇1 = 250 − 200 = 50𝐶 C

∆𝑇2 − ∆𝑇1 291.85 − 50

∆𝑇𝐿𝑀𝑇𝐷 = = = 137.08 𝐶
∆𝑇 291.85
𝐼𝑛 (∆𝑇2 ) 𝐼𝑛 ( )
1 50

• Step 3: determining the tube sizes for inner and shell pipe:

We're going to use inner pipe OD=25.4mm, Shell pipe OD=60.33mm, Inner pipe
ID=23.4mm and shell pipe ID = 58.33mm and thickness =2m (using T3 in Appendix A)

• Step 4: calculating the area for annulus and inner side:

For inner side

𝐷𝑒 = 𝐷𝑖

𝐷𝑖 2 0.02342
𝐴𝑓 = 𝜋 =𝜋 = 0.0004𝑚2
4 4

For annulus side

𝐷𝑒 = 𝐷1 − 𝐷𝑜 = 0.05833 − 0.0254 = 0.03293𝑚

𝐷12 − 𝐷𝑜2
𝐴𝑓 = 𝜋 = 0.002165523 𝑚2
4

Where,

Di : Inside Pipe Inner Diameter D1=outside pipe inner diamater

Do: Inside Pipe Outer Diameter

99

• Step 5: Calculate velocity (V), Reynolds No. (Re) and Prandtl No. (Pr) number for each
stream.

For inner

4 ∗ 𝑚̇
𝑅𝑒 = = 8706 (𝑡𝑢𝑟𝑏𝑙𝑒𝑛𝑡)
𝜋 ∗ 𝐷𝑖 ∗ 𝜇
𝑢
𝑃𝑟 = 𝐶𝑝 ∗ = 3.0824
𝑘

For annulus

4 ∗ 𝑚̇
𝑅𝑒 = = 2483.87 (𝑡𝑢𝑟𝑏𝑙𝑒𝑛𝑡)
𝜋 ∗ 𝐷𝑖 ∗ 𝜇

𝑃𝑟 = (𝐶𝑝 𝜇)/ (𝑘) = 0.86992

• Step 6: For Transient & Turbulent Flow (Re > 2300), Petukhov and Kirillov equation
modified by Gnielinski can be used.
𝑓 𝐷𝑒
( ) (𝑅𝑒 − 1000)𝑃𝑟 (1 + ) 2
8 𝐿
𝑁𝑢 = 3
𝑓 𝑃𝑟2
[1 + 12.7 (8) 0.5 ( 3 − 1)]

𝑓 = (0.782 ∗ 𝑙𝑛(𝑅𝑒) − 1.51) − 2

Where,

• L: Length of Double Pipe Exchanger

• μw : Viscosity of fluid at wall temperature

• Nu : Nusselts Number (h.De / k)

For inner ((Nu=423.04) and f=(0.019))

For Annulus ((Nu=551.29) and f=(0.036))

100

• Step 7: calculating heat transfer coefficient:

𝑛𝑢. 𝑘
ℎ=
𝐷

for inner h=575 W/m2.C

for annulus h=6809 W/m2.C

• step 8:calculating wall temperature.

𝑇𝑊 = (ℎ𝑖𝑡𝐴𝑣𝑒 + ℎ𝑜𝑇𝐴𝑣𝑒𝐷𝑜/𝐷𝑖)/(ℎ𝑖 + ℎ𝑜𝐷𝑜/𝐷𝑖) = 38.15

• Step 9: calculating the overall heat transfer coefficient:

𝐷𝑜
1 𝐷𝑜 𝑙𝑛 ( 𝐷𝑖 ) 1 𝐷𝑜
= . 𝐷𝑖 + 𝐷𝑜. + + 𝑅𝑖. + 𝑅𝑜 = 0.002𝑊/(𝑚. 𝑐)
𝑈 ℎ𝑖 2𝑘𝑡 ℎ𝑜 𝐷𝑖

• Step 10: calculate the area and length of the pipe:

𝐴𝑟𝑒𝑎 = 𝑄 / (𝑈 ∗ 𝐿𝑀𝑇𝐷 ) = 8.11𝑚2

𝐿 = 𝐴𝑟𝑒𝑎 / (𝜋 ∗ 𝐷𝑜) = 29𝑚

• Step 11 calculate number of hairpins:

𝐿 95
𝑁= = =3
32 𝑓𝑡 32
Where: 32 assume in hairpin.
• step 12: calculating the pressure drop using
𝒇 ∗ 𝑳 ∗ 𝑮𝟐
∆𝑷 =
𝟕. 𝟓 ∗ 𝟏𝟎𝟏𝟐 ∗ 𝑫𝒆 ∗ 𝑺𝑮
(f): is the friction factor for the annulus/inner side. f = 0.3673 * Re -0.2314
ΔP: Pressure Drop in PSI
SG: Specific Gravity of fluid (density of fluid/density of water at that temperature)
G: Mass Flux ( W / Af ) in (lb/h.ft²)
(De): is the equivalent diameter of the annulus/inner (In)
101

For inner
∆𝑃 = 0.008𝑝𝑎

For annulus

∆𝑃 = 0.000689𝑝𝑎
102

HEAT EXCHANGER SPECIFICATION SHEET

EQUIPMENT NAME AND TYPE: double pipe heat exchanger (E-106)

SERVICE: Heater

FLUID PROPERTIES DATA: ANNULUS SIDE INNER SIDE

FLUID STATE vapor vapor
TEMPERATURE IN (OC) 250 143.5
TEMPERATURE OUT (OC) 250 200
DENSITY (KG/M3) 400.6037 6.58209
VISCOSITY (CP) 0.061175 0.014532
LATENT HEAT (KJ/KG) 1661.82 -
CP (KJ/KG.C) 4.63225 2.176318
THERMAL CONDUCTIVITY (W/M.C) 0.32575 0.035455
PRESSURE (BAR) 46.9 5

PROCESS DATA: ANNULUS SIDE INNER SIDE

HEAT DUTY (KW) 65.0192 -
FLOW RATE (KG/S) 0.03912533 0.538708567
FOULING FACTOR (M2.K/W) 0.0013 0.0002
PRESSURE DROP (bar) - -
U CALULCATED (W/M2.K) 194.3826134 -

CONSTRUCTION DATA:
HEAT TRANSFER AREA (M2): 4.476390802
INNER PIPE OD (MM): 25.4
SHELL PIPE OD (MM): 60.33
INNER PIPE ID (MM): 23.4
SHELL PIPE ID (MM): 58.33
MATERIAL USED: Carbon steel
OVERALL LENGTH (M): 56

Table 5-15Specification sheet for E-106

103

HEAT EXCHANGER SPECIFICATION SHEET

EQUIPMENT NAME AND TYPE: double pipe heat exchanger (E-104)

SERVICE: Cooler

FLUID PROPERTIES DATA: SHELLSIDE INNER SIDE

FLUID STATE liquid liquid
TEMPERATURE IN (OC) 30 56.671
TEMPERATURE OUT (OC) 45 44.856
DENSITY (KG/M3) 981.7855 676.205
VISCOSITY (CP) 0.715553 0.379294
LATENT HEAT (KJ/KG) - -
CP (KJ/KG.C) 4.17071 2.249593
THERMAL CONDUCTIVITY (W/M.C) 0.622506 0.118155
PRESSURE (BAR) 4.2 1

PROCESS DATA: ANNULUS SIDE INNER SIDE

HEAT DUTY (KW) 45.59374362 -
FLOW RATE (KG/S) 0.728792616 1.715419343
FOULING FACTOR (M2.K/W) 0.0002 0.0002
PRESSURE DROP (bar) - -
TUBE VELOCITY (M/S) - -
U CALULCATED (W/M2.K) 425.826 -

CONSTRUCTION DATA:
HEAT TRANSFER AREA (M2): 8.11
INNER PIPE OD (MM): 88.9
SHELL PIPE OD (MM): 141.3
INNER PIPE ID (MM): 86.9
SHELL PIPE ID (MM): 139.3
MATERIAL USED: Carbon steel
OVERALL LENGTH (M): 29
Table 5-16 Specification sheet for E-104
104

HEAT EXCHANGER SPECIFICATION SHEET

EQUIPMENT NAME AND TYPE: double pipe heat exchanger (E-105)

SERVICE: Heater

FLUID PROPERTIES DATA: ANNULUS SIDE INNER SIDE

FLUID STATE vapor liquid
TEMPERATURE IN (OC) 250 -41.852
TEMPERATURE OUT (OC) 250 200
DENSITY (KG/M3) 400.6037 301.0263
VISCOSITY (CP) 0.061175 0.123947
LATENT HEAT (KJ/KG) 1661.82 -
CP (KJ/KG.C) 4.63225 1.863733
THERMAL CONDUCTIVITY (W/M.C) 0.32575 0.074942
PRESSURE (BAR) 4.2 1

PROCESS DATA: ANNULUS SIDE INNER SIDE

HEAT DUTY (KW) 16.60575152 -
FLOW RATE (KG/S) 0.00992 0.019833
FOULING FACTOR (M2.K/W) 0.0002 0.0002
PRESSURE DROP (bar) - -
U CALULCATED (W/M2.K) 30.87080501 -

CONSTRUCTION DATA:
HEAT TRANSFER AREA (M2): 3.9238630
INNER PIPE OD (MM): 25.4
SHELL PIPE OD (MM): 60.33
INNER PIPE ID (MM): 23.4
SHELL PIPE ID (MM): 58.33
MATERIAL USED: Carbon steel
OVERALL LENGTH (M): 49.17340215

Table 5-17 Specification sheet for E-105

105

5.6.3 SUMMARY TABLE FOR HE DESIGN:

Table 5-18 Summary table for shell and tube HE

Paramter E-101 E-102 E-103

Type Shell and tube Shell and tube Shell and tube

Heat duty (KW) 674.0149 82.569 1238.82

LMTD © 127.9 71.6 71.7
Tube side HTC 1094.687 246.6 138
(W/m2.C)

Shell side HTC 1717.29 209 6261

(W/m2.C)

OHTC (W/m2.C) 288.5153 95.5 127.9

Heat transfer area (m2) 20 14 147
PD tube/shell(bar) 0.184/0.0320 0.023/0.000017 0.35/0.074

Table 5-19 Summary table for DP HE AND Thermo syphon reboiler

Paramter E-104 E-105 E-106 Condenser Reboiler

Type DP DP DP DP Thermo
Syhon

Heat duty (KW) 45.59 16.605 65 17.85 675

LMTD © 13.2 137.7 74.7 11.5 -

Inner side HTC 575.2 160.6 3638.7 604.6 56.65

(W/m2.C)

OHTC (W/m2.C) 425.8 30.87 194.4 451.47 1516

Heat transfer area 8 4 4.5 3.44 17.8

(m2)
106

6 CHAPTER 6: ECONOMIC ANALYSIS AND COST

ESTIMATION.
Chemical processes serve the purpose of generating profit by transforming materials of low market
value into high-value products. To evaluate the profitability of a project, it is essential to estimate
the required investment and production costs. This chapter provides an initial cost estimation for
the production of N-Octane. The estimation process involves determining the fixed capital cost by
evaluating the cost of major equipment purchases, as well as estimating the manufacturing costs.
Additionally, a cash flow analysis is conducted both before and after energy integration. All these
steps were carried out using the CAPCOST program, which is a Microsoft Excel macro-enabled
file designed for calculating equipment costs, total plant cost, manufacturing expenses, and cash
flow analysis. The program was specifically developed to complement the textbook "Analysis,
Synthesis and Design of Chemical Processes" by Turton, Shaeiwitz, Bhattacharyya, and Whiting,
and it is available through Prentice Hall Publishing.

6.1 FIXED CAPITAL INVESTMENT COST:

The estimation of capital investment cost is a crucial aspect in the design of industrial plants. It
encompasses both fixed-capital investment and working capital investment. Fixed-capital
investment refers to the substantial amount of money required before an industrial plant can
commence operations. This investment is used to procure and install the necessary machinery and
equipment, as well as cover expenses related to land, building, and service facilities. On the other
hand, working capital investment is essential for day-to-day operations, including payment of
salaries, maintenance of raw materials and products, and handling other immediate cash
requirements.

The estimation of fixed capital investment takes into account various factors that influence the
purchased cost of equipment. These factors include the inflation rate (index CEPC), equipment
capacity, material of construction for each equipment (Fm), operating pressure (Fp), operating
temperature (FT), and bare module factor (FBM). To evaluate these factors, cost estimation is
performed using the CAPCOST Excel sheet.
107

The actual purchase cost of each equipment is referred to as the Bare Module Cost. This cost
includes both direct and indirect expenses. Direct costs encompass the equipment cost, materials
required for installation, and labor involved in the installation process. Indirect costs include
expenses such as freight, insurance, taxes, and construction costs. These costs are represented by
the Bare Module factor. The calculation of this cost is based on the index year 2023.
108

Table 6-1 Bare Module cost of equipment

Base Equipment Base Bare Module

Purchased Bare Module
Equipment Cost $ Cost $
Equipment Cost $ Cost $

Compressors
C-101 603,000 1,650,000 603,000 1,650,000
C-102 603,000 1,650,000 603,000 1,650,000
Drivers
D-101 185,000 278,000 185,000 278,000
D-102 107,000 161,000 107,000 161,000
Heat
Exchangers
E-101 38,800 125,000 36,900 121,000
E-102 45,400 137,000 37,800 125,000
E-103 54,900 181,000 54,900 181,000
E-104 7,230 23,800 7,230 23,800
E-105 6,230 20,500 6,230 20,500
E-106 6,660 21,600 6,500 21,400
Condenser 6,050 19,900 6,050 19,900
Reboiler 45,900 151,000 45,900 151,000
Pump
P-101 15,300 39,300 9,870 32,000
Tower
T-101 72,200 131,000 33,300 91,800
Mixer
MIXER 63,400 87,400 63,400 87,400
Reactor
R-101 43,600 143,000 43,600 143,000
Vessel
V-101 82,400 169,000 8,450 34,400
109

2% 2%
1% 2% Compressor
3%
Driver
14%
Exchangers
9% Pumps
67%
Tower
Mixer
Reactor
Vessel

Figure 6-1 Distribution of Equipment cost in N-octane process

6.2 GRASS ROOTS AND TOTAL MODULE COST:

Total module cost is the cost of making small to moderate expansion or modifications of an
existing plant. It is a function of bare module cost (CBM). And it is evaluated as:

CTM = 1.18 ∑CBM

Grass roots refers to a completely new facility in which the construction is on undeveloped land.
It. It depends on both total bare module cost at base conditions (CBMo) and total module cost (CTM)
and it can be estimated as:

CGR = CTM + 0.5 CBMo

By using CAPCOST, Grassroots cost estimated to be ($8,290,000) and total module cost
($5,890,000). Since we are constructing a new facility in this project, the fixed capital investment
will be equal to grassroots cost.
110

6.3 COST OF MANUFACTURING:

The cost of manufacturing encompasses both the expenses incurred in acquiring raw materials and
the expenses involved in transforming these materials into finished products. Numerous factors
play a role in determining the manufacturing cost of chemicals:

• DIRECT MANUFACTURING COSTS: Operating expenses that fluctuate in accordance

with the production rate encompass various elements, including but not limited to raw
materials, utilities, waste treatment, and labor costs associated with operations.

• FIXED MANUFACTURING COSTS: These expenses remain unaffected by fluctuations

in production volume and are incurred at fixed rates regardless of whether the facility is
operational. Examples include property taxes, insurance premiums, and depreciation costs.

• GENERAL EXPENSES: Costs associated with management level and administration

activities include management, sales, financing, and research functions.

The cost of manufacturing, (COMd), can be determined by the following equation:

C𝑂𝑀𝑑 = 0.18 𝐹𝐶𝐼 + 2.73 𝐶𝑂𝐿 + 1.23 (𝐶𝑈𝑇 + 𝐶𝑊𝑇 + 𝐶𝑅𝑀)

When the following costs are known:

1. Fixed capital investment (FCI)

2. Cost of operating labor (COL)

3. Cost of utilities (CUT)

4. Cost of waste treatment (CWT)

5. Cost of raw materials (CRM)

This equation does not include depreciation, because this term varies according to the used
depreciation method. More details about individual terms in the equation are discussed in the
following sub-sections.
111

6.3.1 FIXED CAPITAL INVESTMENT (FCI):

The FCI is estimated in section 9.2 without land and found to be ($8,290,000). The price of land is
assumed to be = $2,500,000.

6.3.2 COST OF OPERATING LABOR (COL):

Calculated using the following equations:

𝐍𝐎𝐋 = (𝟔. 𝟐𝟗 + 𝟑𝟏. 𝟕 𝐱 𝐩𝟐 + 𝟎. 𝟑𝟐𝐍𝐧𝐩)𝟎.𝟓

𝐍𝐎𝐋 : number of operator per shift

p: number of particulate solid steps

Nnp: number of non − particulate solid steps

Table 6-2 Nnp of non-particulate solid steps

Equipment NO. of Equipment 𝐍𝐧𝐩

Compressors 2 2
Exchangers 8 8
Heaters/ Furnaces 0 0
Reactors 1 1
Towers 1 1
Total 12

𝐍𝐨𝐥 = (𝟔. 𝟐𝟗 + 𝟑𝟏. 𝟕 𝐱 (𝟎)𝟐 + 𝟎. 𝟑𝟐(𝟏𝟐))𝟎.𝟓

𝐍𝐨𝐥 = 3 operators per shift

Number of Operators Per Shift (NOL):

112

1. Typical operator working hours: 49 weeks where 3 weeks' time off for vacation and sick leave.
2. Number of shifts / operator / year = 49 weeks/year ×5 shifts/week = 245 shifts.

3. Number of shifts required / year = 3 shifts/day ×365 day/year = 1095.

4. Number of operators required to provide this of shifts = [Number of shifts required / year] /
[Number of shifts / operator / year] =1095/245 = 4.5 operators per shift to run a chemical plant.

Operating labor = 𝑁𝑂𝐿 × 𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑜𝑝𝑒𝑟𝑎𝑡𝑜𝑟s

Operating labor = 2.93 x 4.5 = 13 operator/year

C𝑶𝑳 = 𝑂𝑝𝑒𝑟𝑎𝑡𝑖𝑛𝑔 𝑙𝑎𝑏𝑜𝑟 × 𝑌𝑒𝑎𝑟𝑙𝑦 𝑤𝑎𝑔𝑒

C𝑶 = 19,198.16$ x 13 = 249,276$

*Yearly wage in Saudi Arabia= 19,198 $/year.

113

6.3.3 COST OF UTILITY (CUT):

The costs of utilities required within the process, and they are directly influenced by the cost of
fuel. The estimated cost of utilities for the process are summarized in the following Table.

Table 6-3 Cost of utility

Equipment Utility Used Actual Usage Annual Utility Cost

C-101 NA
C-102 NA
D-101 Electricity 201 kilowatts $ 135,000
D-102 Electricity 97.6 kilowatts $ 65,700
E-101 High-Pressure Steam 2430 MJ/h $ 114,300
E-102 High-Pressure Steam 297 MJ/h $ 14,000
E-103 Cooling Water 4460 MJ/h $ 14,000
E-104 Cooling Water 164 MJ/h $ 520
E-105 High-Pressure Steam 59.8 MJ/h $ 2,815
E-106 High-Pressure Steam 234 MJ/h $ 11,020
Condenser Cooling Water 64.3 MJ/h $ 202
Reboiler High-Pressure Steam 2430 MJ/h $ 114,400
P-101 Electricity 0.901 kilowatts $ 580
R-101 Cooling Water -9439.2 MJ/h $ (29,693)
114

9%

40%
Electricity

51% High-Pressure Steam

Cooling Water

Figure 6-2 Distribution of utility in N-octane process

6.3.4 COST OF MATERIALS:

Raw materials costs make a considerable contribution to the cost of manufacturing and hence it is
essential to know the current raw material cost. The raw materials used for the n-octane production
process is ethylene and iso-butane. The cost of raw material from CAPCOST:

Annual cost of raw materials = 𝑤𝑜𝑟𝑘𝑖𝑛𝑔 ℎ𝑜𝑢𝑟𝑠 ∗ 𝑓𝑙𝑜𝑤 𝑟𝑎𝑡𝑒 ∗ 𝑚𝑎𝑡𝑒𝑟𝑖𝑎𝑙 𝑐𝑜𝑠𝑡 𝑝𝑒𝑟 𝐾𝐺

Working hours = 8000 h/yr

Table 6-4 Cost of raw materials

Material name Classification Flow rate (kg/h) Cost per KG ($) Total cost ($)

Iso-butane Raw material 3106.7278 0.691 17,856,246

Ethylene Raw material 2999 0.862 21,513,246

Zeolite Catalyst 1 5$ 40,000

The total raw material cost = 39,378,764$

115

The Cost of Manufacturing (𝐶𝑂𝑀𝑑 ) without depreciation and cost of land was calculated using
the following equation:

𝐶𝑂𝑀𝑑 = 1.23 [𝐶𝑅𝑀 + 𝐶𝑊𝑇 + 𝐶𝑈𝑇 ] + 2.76 COL + 0.18 FCIL

𝐶𝑂𝑀𝑑 = 1.23 ∗ [393,787,64 + 0 + 443,000] + 2.76 ∗ 268,773 + 0.18 ∗ 8,290,000

𝐶𝑂𝑀𝑑 = 51,214,784

Table 6-5 Economic information calculated from given information

CRM (Raw Materials Costs) 39,378,764$

CUT (Cost of Utilities) 443,000$
CWT (Waste Treatment Costs) -
COL (Cost of Operating Labor) 268,773$

6.4 EQUIVALENT ANNUALIZED OPERATING COST (EAOC):

Assuming that the interest rate in 10%, and the project lifetime of 10 is annualized and added to
the cost of manufacturing, then the Equivalent annualized operating cost (EAOC) is calculated by
the following equation:

𝐸𝐴𝑂𝐶 = 𝐹𝐶𝐼𝐿 × 𝐶𝑎𝑝𝑖𝑡𝑎𝑙 𝑅𝑒𝑐𝑜𝑣𝑒𝑟𝑦 𝐹𝑎𝑐𝑡𝑜𝑟 + 𝐶𝑂𝑀𝑑

0.1 ∗ (1 + 0.1)10
𝐸𝐴𝑂𝐶 = 8,290,000 ∗ + 51,214,784
0.1 ∗ (1 + 0.1)10 − 1

𝐸𝐴𝑂𝐶 = 483,115,46.45

Where

𝐹𝐶𝐼𝐿 : 𝐹𝑖𝑥𝑒𝑑 𝑐𝑎𝑝𝑖𝑡𝑎𝑙 𝑖𝑛𝑣𝑒𝑠𝑡𝑚𝑒𝑛𝑡 𝑤𝑖𝑡ℎ𝑜𝑢𝑡 𝑐𝑜𝑠𝑡 𝑜𝑓 𝑙𝑎𝑛𝑑.

𝐶𝑂𝑀𝑑 : 𝐶𝑜𝑠𝑡 𝑜𝑓 𝑚𝑎𝑛𝑢𝑓𝑎𝑐𝑡𝑢𝑟𝑖𝑛𝑔 𝑤𝑖𝑡ℎ𝑜𝑢𝑡 𝑑𝑒𝑝𝑟𝑒𝑐𝑖𝑎𝑡𝑖𝑜𝑛.

10: 𝐸𝑥𝑝𝑒𝑐𝑡𝑒𝑑 𝑙𝑖𝑓𝑒 𝑜𝑓 𝑡ℎ𝑒 𝑝𝑙𝑎𝑛𝑡.

0.1: 𝐹𝑟𝑎𝑐𝑡𝑖𝑜𝑛𝑎𝑙 𝑖𝑛𝑡𝑒𝑟𝑒𝑠𝑡 𝑟𝑎𝑡𝑒.

116

6.5 REVENUE ESTIMATE

Revenue is the total amount of money generated by a company from its normal business
operations, typically through the sale of goods and services to customers. Revenue is a key
indicator of a company's financial performance and its ability to generate sales.

Table 6-6 Product price

Product Price ($/kg) Flowrate (kg/h) Annual Cost

N-octane 2.10$ 6103.80 106,671,177$

According to CAPCOST software, the total revenue that is achieved from the n-octane production
is equal to

106,671,177 $

6.6 PROFITABILITY ANALYSIS

The assessment of how much profit may be made from a certain project is known as profitability.
Knowing if a project will be lucrative and how much money can be made is important before
investing in it. The three fundamental concepts of time, cash, and interest rate are employed to
evaluate the profitability analysis.

6.6.1 CASH FLOW DIAGRAMS

Cash flow is a tool used to represent the cost flow; which decreases and increasing through a
project life. There are two type of cash flow, discounted cash flow and undiscounted cash flow.

In discounted cash-flow rate of return the cost of capital can be taken as the average rate of return
for the company earns on its capital, or it can be designated as the minimum acceptable return for
the project. So, cash flows include initial investments, cost of manufacturing costs, project
earnings, and depreciations as well as the salvage value of equipment at the end of the project.
117

Table 6-7 Discounted profitabilty criterion

Net Present Value (millions) 214.99

Discounted Cash Flow Rate of Return 9.82%
Discounted Payback Period (years) 9.1

Figure 6-3 Discounted cash flow diagram

For the production of n-octane Discounted Profitability cash flow of a project through a project
life period of ten years. Which describes the profitability pattern of a project and gives the
breakeven at three years and six months.

Table 6-8 Non-discounted Profitability criterion

Cumulative Cash Position (millions) 437.63
Rate of Return on Investment 527.90%
Payback Period (years) 5.4
118

NON-DISCOUNTED CASH LOW DIAGRAM

470.00
Project value (million of dollers)

370.00

270.00

170.00

70.00

(30.00) 0 2 4 6 8 10 12 14
Project life (Years

Figure 6-4 Non -discounted cash flow diagram.

For the production of n-octane Non-Discounted Profitability cash flow of a project through a
project life period through ten years. Which describe a profitability pattern of project and give the
breakeven at two years and two months.
119

7 CHAPTER 7: PROCESS CONTROL

Control system engineering makes sure that increasing productivity and strengthening your
company's best practices are done strategically. Eliminating unnecessary manual controls and
lowering the possibility of costly human error are goals, a system of controls ought to be
assessed often to make sure the procedures are operating successfully, safely, and efficiently. This
method offers the greatest client service while abiding by industry norms.

7.1 COMPRESSOR CONTROL LOOP:

The most important variable to be controlled in a compressor is the pressure as it is a pressure
increasing device. The pressure is controlled by the rotation speed so we can variate the pressure
by varying the power of the turbine thus the rotation seed. And as a single phase compressor we
don’t need a temperature control loop.

Figure 7-1 Compressor control loop

120

7.2 FLASH DRUM CONTROL LOOP:

Any process containing vapor phase needs a pressure control loop due to the fatal effects that
variation of pressure can cause, and in our flash drum which it a phase separator the pressure can
affect the efficiency of the separation process. The second variable to be controlled is the liquid
level in drum to insure we have the best separation efficiency.

Figure 7-2 Flash drum control loop

121

7.3 REACTOR CONTROL LOOP

The reaction is highly exothermic and the reactor operates isothermally. So, the temperature inside
the reactor must be controlled to avoid a runaway. The temperature can be controlled by a cooling
jacket by varying the flow rate of inlet cooling water. A cascade control was used such that the
temperature controller provides a “remote” setpoint to the flow controller, which throttles the flow
control valve to achieve the desired rate of cooling water flow.

In addition, the reaction takes place in the gas phase, so the control loop on pressure must be set .

Figure 7-3 : Reactor Control Loop

122

7.4 HEAT EXCHANGER CONTROL LOOP

Heat exchanger’s main purpose is to heat up or cool down the fluids, and we need to control the
HE by regulate the amount of energy (Q) needed by controlling the amount of temperature out of
the system. By using control feed backward loop as shown. We use feed backward control because
it doesn’t require a perfect system design and it’s the most used control loop by a lot of companies
for HE. Its measures and control a controlled variable for our HE it’s the Temperature and it
changes the manipulated variable (Q) to match our T (set point)

Figure 7-4 Heat exchanger control loop

123

7.5 DISTILLATION CONTROL LOOP

Controlling a distillation column involves precise control over various factors like temperature,
pressure, flow rates, and levels to ensure optimal separation and production in chemical processes.
This control is essential for get product specifications efficiently.

Pressure control is use for safe operation, preventing issues like flooding or vaporization.

Temperature control enhances separation efficiency, ensuring higher purity product streams and
consistent quality. It also promotes energy efficiency, reduces equipment damage, and enhances
process stability, allowing quick adaptation to changing conditions.

Level control on each tray of the distillation column is crucial for optimizing separation efficiency
by managing liquid and vapor phase residence times effectively.

Implementing comprehensive control measures and safety systems ensures efficient separation and
safeguards the integrity of the distillation process.

Figure 7-5 Distillation control loop

124

7.6 PUMP CONTROL LOOP

A flow control pump control loop is a system that automatically maintains a desired flow rate of
liquid in a pipe. Here are the main components:

Controller: This device compares the measured flow rate (process variable) to the desired flow
rate (setpoint).

Control valve: By opening or closing the valve, the pressure drop across the valve is adjusted,
which in turn affects the flow rate.

This feedback loop ensures the pump maintains the desired flow rate within a specific range.

Figure
Figure7-6
7-7Pump controlloop
Pump control loop
125

8 CHAPTER 8: SAFETY AND ENVIROMRNTAL

ASPECT

8.1 INTRODUCTION
Environment, health, and safety (EHS) is a multidisciplinary field that focuses on the protection
of human health and the environment in various settings, including worksites, communities, and
public spaces. The main objectives of EHS are to identify and mitigate potential hazards, prevent
accidents and promote a safe and healthy living and working environment.

Government EHS departments, such as the Environmental Protection Agency (EPA) and
Occupational Safety and Health Administration (OSHA) in the US, deploy EHS regulations to
enforce adherence to standards that promote collective environmental protection, occupational
safety, and health and wellness. Similarly, international bodies like the International Organization
for Standardization (ISO) develop standards and provide certifications to entities that adhere to
those standards.

In some regions and contexts, EHS is referred to as HSE (Health, Safety and Environment) among
many other similar acronyms like EHS, SHE, OHS, WHS, QHSE, HSSE, and more, but these
likely refer to the same discipline.

EHS comprises three interrelated disciplines:

1. Environmental protection

This focuses on safeguarding the environment from pollution and degradation. It involves
monitoring and controlling factors such as air quality, water quality, soil contamination, and waste
management. Environmental management and protection measures aim to reduce the negative
impact of human activities, emissions and hazardous materials on ecosystems, wildlife and natural
resources.

2. Occupational safety

Workplace safety addresses the protection of workers' health and well-being in the workplace. It
involves identifying and mitigating potential hazards that can cause injuries, illnesses, or accidents
to employees. Occupational safety measures include providing appropriate personal protective
126

equipment (PPE), training employees on safety programs, conducting safety inspections, and
implementing safety procedures to create a working environment that adheres to safety
regulations. In 2021, 5,190 workers in the US suffered fatal work injuries, and EHS measures aim
to bring that number down.1

3. Health and wellness

This component focuses on promoting the overall health and well-being of stakeholders and
communities. It includes addressing public health concerns, conducting health risk assessments,
monitoring disease outbreaks and implementing health promotion program

8.1.1 GENERAL PLANT SAFETY AND PERSONAL PROTECTIVE EQUIPMENT

1. Hard Hats

Figure 8-1 Hard Hat (PPE)

Hard hats and bump caps provide adequate protection for industrial workers from head injuries
caused by fixed, falling, or flying objects. Protective hats must be penetration-, shock-, and water-
resistant as well as being slow-burning.

There are three industrial classes of hard hats:

• Class A: Provides impact and penetration resistance and some protection from electrical
hazards that may come with job tasks.
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• Class B: As well as providing impact and penetration resistance, Class B hard hats provide
the highest level of protection against electrical hazards, including high-voltage shock and
burn protection.

• Class C: Provides some impact protection but no protection from electrical hazards.

OSHA regulations also require employers to ensure that their employees cover and protect long
hair to prevent it from being caught in machinery.

When hard hats, industrial safety helmets, or other head protection PPE sustain damage or impact
— even if the damage is not visible to the human eye — it must be replaced.

2. Leggings, Foot Guards, and Safety Shoes

Figure 8-2 Leggings, foot guard and safety shoes (PPE)

Leggings, foot guards, safety shoes, and other forms of leg and foot protection help protect workers
from a range of workplace hazards including falling, rolling, or sharp objects; wet, slippery, and
hot surfaces; and electrical hazards.

This personal protective equipment includes:

• Protective leggings: Typically made from leather or aluminized rayon, protective leggings
are fitted with safety snaps for easy removal and serve to protect the wearer’s legs and feet.

• Metatarsal guards: This type of foot protection is strapped to the outside of the wearer’s
shoes to protect the instep.
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• Toe guards: Typically made from steel, aluminum, or plastic, these fit over the wearer’s
toes to protect from impact.

• Shin guards: These provide protection for the lower legs and feet.

• Safety boots or shoes: A range of special-purpose footwear such as electrically conductive

shoes, which protect against static electricity build-up, can be acquired by employers. Slip
resistant soles may also be best for wet or icy environments.

3. Ear Plugs, Earmuffs, and Other Hearing Protection

Figure 8-3 Earplugs, Earmuffs, and other protection

(PPE)

When worn correctly, ear plugs and earmuffs are used to protect workers from exposure to
excessive noise, which can lead to irreparable hearing damage and increased stress. In a workplace
where employees are consistently subjected to high levels of noise, workers should be fitted for
specially molded ear plugs. The louder and more constant the noise, the less time an employee
should be expected to work without adequate hearing protection.
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4. Hand and Arm Protection

Figure 8-4 Hand and arm protection

Gloves, finger guards, and arm coverings will protect employees from the skin damage caused by
cuts, chemical and thermal burns, and punctures. Depending on the nature of the employee’s work
and their risk of exposure, hand and arm protection can provide different levels of thermal
protection and cater to different grip requirements. Gloves might be made of leather, canvas, or
metal mesh; fabric; or chemical- and liquid-resistant materials. Insulating rubber can help protect
from electrical currents whereas insulated gloves can keep skin safe from extreme temperatures.

5. Eye Protection and Safety Glasses

Figure 8-5 Eye protection and safety

Protective eyewear is important in certain workplaces to shield employees’ eyes from flying
particles, hot liquids, molten metal, chemical gases, and harmful radiation. This eye protection
must fit closely and comfortably to the wearer’s face, be cleanable, and not restrict vision or
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movement. Eye protection includes safety goggles, safety glasses, welding shields, chemical
splash goggles, and laser safety goggles. These can also help protect eyes from being exposed to
potentially infectious materials and body fluids.

6. Surgical Face Masks

Figure 8-6 Surgical face mask

A surgical mask — often referred to as a face mask — is a loose-fitting, disposable device that
covers the wearer’s mouth and nose to create a physical barrier between them and people in their
immediate environment.

This PPE lessens safety risks and serves to protect the wearer from large particle droplets or
splatters that could contain potentially infectious material as well as reduce the saliva and
respiratory secretions the wearer passes on to others.
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7. Respirators

Figure 8-7 Respirators

Respirators are a form of respiratory protective equipment and have long been used in a
manufacturing setting to protect employees from inhaling air contaminated with harmful dust,
fumes, gases, or sprays. This type of breathing apparatus must fit closely to the face and cover the
nose and mouth to be effective.

N95 filtering facepiece respirators are most commonly used and recommended by OSHA. Once
manufactured, a sample from each batch is tested for flammability, breathing and splash resistance,
particle filtration efficiency, and bacteria filtration efficiency.

More recently, N95 respirators have become essential respiratory equipment in the fight against
COVID-19. When unavailable, more intricate alternatives such as powered air-purifying
respirators (PAPRs), supplied-air respirators (SARs), or high-efficiency particulate arrestance
(HEPA) can be used.
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8. Face Shields

Figure 8-8 Face shield

Face shields consist of a visor, a lightweight plastic or metal frame, and a suspension system that
attaches the shield to the head of the wearer. Providing full face protection, this PPE is typically
worn on top of masks or goggles to prevent the inhalation of toxic or harmful substances, body
fluids, or, as in the case of COVID-19, virus-carrying aerosol droplets.

Employers looking to source PPE, like face shields, for their workforce must thoroughly research
and evaluate prospective suppliers to reduce the risk of purchasing counterfeit PPE. In the wake
of COVID-19, several manufacturers have retrofitted their businesses to help meet the increasing
demand for PPE.

With this in mind, it’s more important than ever before to scrutinize PPE suppliers. Consult
government resource lists to find legitimate manufacturers, check supplier certifications, insist on
checking product samples for legitimacy and quality, and closely interrogate contracts.
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9. Proximity Sensors

Figure 8-9 Proximity sensors

Proximity sensors are a new addition to the list of PPE, with their development spurred by the
COVID-19 pandemic. With proper use, this device is typically used to indicate the proximity of a
user to a hazardous object but has been updated by product developers to help manufacturing
employees adhere to the six-foot separation guidelines. This is also a means to track exposure to
COVID-19 within the workplace.
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10. Body Shields and Protective Clothing

Figure 8-10 Body shield and protective clothing

In particularly hazardous conditions, workers might be required to protect their entire body. Body
protection comes in the form of jackets, aprons, lab coats, overalls, and full body suits. They are
made from a range of materials including fire-retardant wool or cotton, rubber, leather, and plastic.

Body protection of this kind must be carefully measured for each employee to ensure a proper fit.
Shields such as jackets or full suits can also double as high visibility clothing if employees are
working in poor weather or low light conditions. As for other types of PPE, safety harnesses are
another important item. These are built for workers who are in situations or environments where
there is a risk of falling.

Regardless of the type of industry, PPE (personal protective equipment) is an essential part of
maintaining a safe workspace.
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8.1.2 NFPA FIRE DIAMONDS AND SDS

NFPA diamond (National Fire Protection Association) is a standard system used for the
identification of the hazards of materials for emergency response. It is used mainly by emergency
personnel to quickly and easily identify the risks posed by hazardous materials. This also helped
determine what, if any, special equipment should be used, procedures followed, or precautions
taken during the initial stages of an emergency response.

The NFPA diamond provides a quick visual representation of the health hazards, flammability,
reactivity, and special hazards that a chemical may pose during a fire.

Figure 8-11 NFPA rating explanation guide

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1. N-octane

Table 8-1 N-octane Information

NIOSH Pocket Guide International Chem Safety Card

Octane OCTANE

CAS Number UN/NA Number DOT Hazard Label

111-65-9 1262 Flammable Liquid

Table 8-2 N-octane NFPA's hazard diamond and its description.

2. Ethylene

Table 8-3 Ethylene Information

NIOSH Pocket Guide International Chem Safety Card

None ETHYLENE

CAS Number UN/NA Number DOT Hazard Label

74-85-1 1962 Flammable Gas

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Table 8-4 Ethylene NFPAS hazard and its description

3. Iso-butane

Table 8-5 Iso-butane information

NIOSH Pocket Guide International Chem Safety Card

Isobutane ISOBUTANE

CAS Number UN/NA Number DOT Hazard Label

75-28-5 1969 Flammable Gas

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Table 8-6 Iso-butane hazard diamond and its description

8.2 HAZARDOUS MATERIAL

Hazardous material encompasses substances that possess the potential to cause harm to living
organisms or the environment, whether in solid, liquid, or gaseous form. These materials can pose
significant risks when inhaled, ingested, or absorbed, either independently or in combination with
other elements. Regulatory bodies such as the Environmental Protection Agency (EPA),
Occupational Safety and Health Administration (OSHA), and Department of Transportation
(DOT) enforce laws to ensure the safe production, handling, storage, transportation, and disposal
of hazardous materials, thereby safeguarding the well-being of workers and the environment.

8.2.1 EXPOSURE AND HEALTH EFFECTS OF MATERIALS

N-octane, iso-butane, and ethylene are widely used in various industrial processes. While they
offer significant utility, it's crucial to understand their potential hazards and associated health
effects:

N-octane: This hydrocarbon is a colorless liquid with a gasoline-like odor. Exposure to n-octane
vapor may result in respiratory irritation and central nervous system depression. In high
concentrations, it poses a risk of asphyxiation in confined spaces due to oxygen displacement.
Additionally, n-octane is highly flammable and may form explosive mixtures with air.
139

Iso-butane: As a flammable gas, iso-butane presents fire and explosion hazards if not handled
properly. Inhalation of iso-butane vapor can cause dizziness, drowsiness, and narcosis. In confined
spaces, it can displace oxygen, leading to suffocation. Adequate ventilation and proper storage
practices are essential to mitigate these risks.

Ethylene: A colorless gas with a faint, sweet odor, poses various hazards in industrial settings.
Prolonged exposure may lead to respiratory irritation, central nervous system depression, and
asphyxiation in confined spaces. Ethylene is highly flammable and can form explosive mixtures
with air. Additionally, skin contact may cause irritation and dermatitis. Strict handling protocols,
proper ventilation, use of personal protective equipment, and thorough training are essential to
minimize these risks and ensure personnel safety.

Given the hazardous nature of these materials, strict adherence to safety protocols, including the
use of personal protective equipment (PPE) and proper engineering controls, is imperative to
prevent accidents and protect human health and the environment.

8.3 EQUIPMENT SAFETY

In the process of producing n-octane from ethylene and iso-butane, various equipment must be
carefully managed to ensure safe operation and minimize hazards. Below are specific precautions
for each equipment:

1. Reactor

Using a fixed bed reactor to produce n-octane from ethylene and isobutane involves several
considerations for safety, efficiency, and product quality. Here are some things that might happen
in terms of safety:

Risk of Fire and Explosion: Both ethylene and isobutane are highly flammable gases. Any leakage
or malfunction in the reactor system could lead to the formation of explosive mixtures.
Implementing robust safety measures such as gas detectors, flame arrestors, and pressure relief
valves is crucial to mitigate this risk.

Temperature Control: The reaction to produce n-octane may be exothermic, meaning it releases
heat. Proper temperature control is essential to prevent runaway reactions and ensure the safety of
the reactor. Cooling systems such as heat exchangers or water jackets may be employed to maintain
the temperature within safe limits.
140

Material Selection: Choose corrosion-resistant materials for construction to prevent degradation

and hazards.

2. Distillation Column

In the safety of distillation column trays, several critical aspects must be addressed to ensure the
integrity of the process and the protection of personnel and assets.

Overpressure Protection: Preventing overpressure situations is often paramount as it can lead to

catastrophic equipment failure and pose significant risks to personnel and the environment.

Leak Prevention: Controlling leaks is crucial for maintaining the integrity of the system and
preventing the release of hazardous materials, which can lead to fires, explosions, or environmental
contamination.

Emergency Shutdown Procedures: Having effective procedures in place to safely shut down the
distillation column in emergencies can help mitigate risks and prevent escalation of incidents.

3. Vessel

For vessels like a flash drum where n-octane, isobutane, and ethylene are processed, material
selection is crucial to ensure safety, durability, and compatibility with the substances involved.

Pressure relief is often the most critical consideration. These vessels manage volatile substances
undergoing rapid phase separation, often leading to substantial pressure buildup if uncontrolled.
Reliable pressure relief devices are crucial to prevent overpressure situations, averting catastrophic
vessel failure or explosions. Adequate venting and ventilation are also essential, mitigating
pressure-related risks and ensuring safe operating conditions within the flash drum.

Overfilling: Overfilling can cause the vessel to fail or spill its contents, which can lead to
environmental damage, fires, or other safety hazards.

4. Compressor

• Constructed from materials resistant to corrosion and suitable for high-pressure operation.

• Equipped with safety features such as pressure relief valves and surge control systems.

• Regular maintenance to ensure seals and bearings are intact and functioning properly.
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• Vibration monitoring systems to detect abnormalities.

• Proper ventilation and cooling systems to prevent overheating.

5. Pump

Centrifugal pumps play a crucial role in industrial operations, but they do come with inherent
hazards that need careful management. Here's an expanded view of the hazards associated with
centrifugal pumps:

• Impeller Integrity: Monitor impeller condition to prevent breakage from corrosion or

fatigue.

• Electrical Hazards: Ensure proper electrical maintenance to prevent shocks or fires.

• Cavitation: Monitor inlet conditions to prevent damage from vapor bubbles.

• Environmental Contamination: Implement leak detection and containment to prevent

spills.

6. Heat Exchanger

Heat exchangers play a vital role in industrial processes, but they are not without their hazards.
Here's an overview of common hazards and safety precautions:

• Tube Corrosion: Monitor and prevent corrosion in heat exchanger tubes to avoid leaks or
ruptures.

• Scaling and Fouling: Implement cleaning procedures to prevent buildup of scale or fouling,
which can reduce heat transfer efficiency.

• Pressure Testing: Conduct regular pressure tests to ensure integrity and detect any leaks or
weaknesses.
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8.4 HAZARD AND OPERABILITY STUDY (HAZOP)

8.4.1 WHAT IS HAZOP?

The HAZOP technique is employed to pinpoint significant process hazards or operability concerns
associated with the process layout. Its objective is to recognize every possible deviation from the
intended design within the facility and to ascertain the potential abnormal factors and negative
outcomes resulting from such deviations. When examining a deviation, it is recommended to
contemplate the worst-case scenario, assuming the absence of any protective measures in the
facilities. Furthermore, the analysis should encompass the most severe consequences that may
arise.

8.4.2 OBJECTIVE OF HAZOP STUDY:

Safety Issues:

• To identifies scenarios that would lead to the release of hazardous or flammable materials
in the atmosphere.

• To chick the safety of the design.

• To improve the safety of an existing facility.

Operability Issues:

• To decide whether or where to build.

• To ensure long-term and trouble-free operation.

• To verify that safety instruments is working optimally.

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8.4.3 HAZOP ANALYSIS:

For this analysis, the relevant variables were Temperature, Pressure, Level, Charge composition,
Concentration, and Flow. The guide words applied were “More”, “Less”, and “None”.

Table 8-7 Example on HAZOP analysis

Case Deviation Causes Consequences Safeguard Recommendations

1 High flow Pumps or The pressure Flow control Making sure the
rate compressors will decrease valve to detect valves work and
operators set so the pumps and solve the system design can
the flow too and problem handle higher flow
high, they compressors rates than needed
may be hurry will need more
and don't pay power to reach
attention needed
pressure
2 Low Fouling or not The reaction Temperature Make sure to clean
temperature enough heat may not occur, control loop to the pipes regularly,
provided to or the phase solve the and the temperature
system separation problem transmitter works
efficiency will well
decrease
3 Low Deviation of Consume more Concentration Taking sample
separation feed power and time control valve every period of
efficiency concentration to get the as well as time to assure the
or higher or needed product temperature quality and hiring
lower and low-quality and pressure an expert team to
temperature product control valves operate the process
and pressure
4 No product Fail in valves Loss on money Temperature Regular chick on
or no reaction and delayed on control loops catalyst and the
occur in the the customers and catalyst reactor temperature
reactor duo to weight chick and the valve
no catalyst or
low
temperature
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8.5 HAZARD ENVIRONMENTAL IMPACT ASSESSMENT

8.5.1 INTRODUCTION OF ENVIRONMENTAL IMPACT ASSESSMENT

The Environmental Impact Assessment (EIA) is a systematic procedure that assesses the potential
environmental consequences of a proposed project or development. It considers the interconnected
socio-economic, cultural, and human-health impacts, encompassing both positive and negative
effects.
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8.5.2 MATERIALS LEAVING THE PROCESS AND THEIR IMPACT ON THE

ENVIRONMENT

N-octane:

Avoid dispersal of spilled material and runoff and contact with soil, waterways, drains and sewers.
Inform the relevant authorities if the product has caused environmental pollution (sewers,
waterways, soil, or air). Water polluting material. May be harmful to the environment if released
in large quantities.

Table 8-8 Control parameter

Long-term value: 2350 mg/m³, 500 ppm n-

PEL
Octane only

Long-term value: 350 mg/m³, 75 ppm Ceiling

REL
limit value: 1800* mg/m³, 385* ppm *15 min

TLV Long-term value: 1401 mg/m³, 300 ppm

Product/ingredient
Result Species Dose Exposure
name

LC50 Inhalation
Rat 25260 ppm 4 hours
Gas
N-Octane
LC50 Inhalation
Rat 118 g/m³ 4 hours
Vapor

LC50 - Oryzias latipes - 0,42 mg/l - 96,0 h

Toxicity to fish mortality
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static test EC50 - Daphnia magna (Water flea)

Toxicity to daphnia and other aquatic
- 0,38 mg/l - 48 h Remarks: (ECHA)
invertebrates

NOEC - Pseudokirchneriella subcapitata

Toxicity to algae Growth inhibition
(microalgae) - 5,8 mg/l - 72 h

LOEC - Oryzias latipes - 0,069 mg/l NOEC -

Toxicity to fish(Chronic toxicity)
Oryzias latipes - 0,028 mg/l

static test NOEC - Daphnia magna (Water

flea) - 0,17 mg/l - 21 d (OECD Test Guideline
Toxicity to daphnia and other aquatic
211) Remarks: (in analogy to similar
invertebrates(Chronic toxicity)
products)

Iso-Butane:

Permissible Limits:

Drinking Water: The Environmental Protection Agency (EPA) typically sets the maximum
contaminant level (MCL) for total VOCs in drinking water at around 5 parts per billion (ppb) or
lower.

Surface Water: To prevent environmental contamination, it is important to minimize

concentrations of iso-butane in surface water. However, the specific regulatory limits may vary
depending on local standards.

Soil: The regulatory limits for iso-butane in soil may not be widely established. In general, it is
recommended to keep soil contamination levels as low as possible to avoid any adverse effects on
human health and the environment.

Ambient Air: The EPA's National Ambient Air Quality Standard (NAAQS) for ozone, which is a
VOC precursor, is set at an average of 70 parts per billion (ppb) over an 8-hour period.
147

Workplace Exposure: The American Conference of Governmental Industrial Hygienists

(ACGIH) has established a Threshold Limit Value-Time-Weighted Average (TLV-TWA) of 800
ppm for butane isomers, including iso-butane, in workplace air.

Ethylene:

Permissible Limits:

Certainly, here are approximate ranges for acceptable thresholds of ethylene in different
environmental contexts:

Ambient Air Quality: Generally, concentrations are maintained below 100 ppb to prevent the
formation of ground-level ozone and minimize potential health impacts. However, specific
regulatory standards may establish lower limits in areas with sensitive ecosystems or high
population density.

Workplace Exposure: Occupational exposure limits (OELs) for ethylene in the workplace
typically range from 200 to 1,000 parts per million (ppm) as a time-weighted average (TWA) over
an 8-hour workday. Short-term exposure limits (STELs) may also be set, ranging from 1,000 to
2,000 ppm over a 15-minute period.

Soil and Water: Ethylene is generally not regulated in soil and water due to its gaseous nature and
low persistence in these environments. However, in the context of agricultural runoff or industrial
discharge, acceptable thresholds for ethylene may be indirectly regulated through broader
regulations on water and soil quality, particularly if its presence contributes to ecosystem
disruption or poses risks to human health

Environmental Release: Acceptable limits for ethylene emissions from industrial sources may be
regulated by environmental agencies, often through permits or emissions standards. These limits
can vary significantly depending on factors such as the industry sector, location, and size of the
facility.
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9 CHAPTER 9: PLANT LAYOUT AND SITE LOCATION

9.1 PLANT LAYOUT:

The main purpose of plant layout is to design and arrange the physical facilities of a manufacturing
plant in a way that optimizes efficiency, productivity, safety, and workflow. Effective plant layout
considers factors such as the flow of materials, equipment placement, space utilization, employee
movement, and safety regulations. A well-designed layout can minimize production bottlenecks,
reduce material handling costs, enhance communication and coordination among workers, and
ultimately improve overall operational performance.

9.1.1 THE MAIN FACTORS TO BE CONSIDERED ARE:

1. Space Utilization: Maximizing the efficient use of available space to accommodate
machinery, equipment, workstations, aisles, and storage areas while minimizing wasted
space.

2. Workflow and Material Flow: Designing the layout to ensure smooth and efficient flow
of materials, products, and information throughout the production process. This includes
minimizing travel distances, reducing congestion, and avoiding bottlenecks.

3. Flexibility and Expansion: Building flexibility into the layout to accommodate changes
in production processes, product lines, or volumes. Additionally, allowing for future
expansion or reconfiguration as business needs evolve.

4. Safety: Ensuring that the layout promotes a safe working environment by minimizing
hazards, providing clear pathways for emergency evacuation, and complying with safety
regulations and standards.

5. Accessibility and Ergonomics: Designing workstations and equipment placement to

optimize accessibility for workers and promote ergonomic principles to reduce the risk of
injuries and fatigue.
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6. Maintenance and Accessibility: Ensuring that machinery and equipment are easily
accessible for maintenance, repair, and cleaning, which helps minimize downtime and
extends equipment lifespan.

7. Communication and Supervision: Arranging work areas to facilitate effective

communication and supervision among workers, supervisors, and managers, fostering
collaboration and teamwork.

8. Utilities and Support Services: Planning for the efficient provision of utilities such as
electricity, water, and ventilation, as well as support services such as restrooms, break
areas, and storage for tools and supplies.

9. Cost Considerations: Balancing the need for an optimal layout with the associated costs
of construction, equipment installation, and ongoing operation, aiming to achieve the best
return on investment.

10. Regulatory Compliance: Ensuring that the layout complies with relevant building codes,
zoning regulations, environmental regulations, and industry standards.

9.1.2 WHY WE NEED 3D PLANT REPRESENTATION?

1. Seeing Everything Better: 3D models help us understand how the plant looks and works,
like looking at a miniature version of it. This makes it easier to plan and build things right.

2. Avoiding Crashes: 3D models can show if things might bump into each other in the plant,
like machines or people. This helps prevent accidents and saves money on fixing things
later.

3. Testing Ideas: Designers can use 3D models to try out different ways of arranging things
in the plant. This helps find the best way to make everything work smoothly.

4. Taking a Virtual Walk: You can explore a 3D model of the plant without actually being
there. This helps people understand how the plant works and what it's like before they start
working there.

5. Planning Fixes: 3D models show where everything is in the plant, so it's easier to plan
when and how to repair things. This saves time and keeps the plant running smoothly.
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9.1.3 THE MAIN PRINCIPLES FOR A PLANT LAYOUT:

1. Distance between major processing equipment in each section should be set based on safety
Considerations and maintenance.
2. Should be according to local and international safety standard

9.1.4 THE MINIMUM SPACING BETWEEN EQUIPMENT’S

The minimum spacing between equipment should be set early in the design. These distances are
set for safety purposes and should be set with both local and national codes in mind. A
comprehensive list of the recommended minimum distances between process equipment is given
by Bausbacher and Hunt. (M= the minimum space required)

Table 9-1 Minimum space for major equipment

Equipment Pumps Compressors Reactors Towers and exchangers

vessels

Pumps M 25 M M M

Compressors M 30 M M

Reactors M 15 M

Towers and M M
vessels

Exchangers M

9.2 PLANT AND SITE LOCATION:

1. Plant location refers to choosing the specific geographical area or region where a
manufacturing facility will be situated.
• Advantages:
❖ Proximity to Raw Materials: Locating the plant near raw material sources reduces
transportation costs and ensures a stable supply chain.
❖ Access to Labor: Choosing a location with a skilled labor force reduces recruitment
challenges and labor costs.
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❖ Market Access: Selecting a site close to target markets decreases transportation costs and
delivery times, enhancing competitiveness.
❖ Infrastructure Availability: Choosing an area with good infrastructure (roads, utilities, etc.)
facilitates smooth operations and logistics.
❖ Government Incentives: Governments may offer tax breaks or other incentives for locating
plants in certain regions, reducing operational costs.

• Disadvantages:
❖ Higher Land Costs: Prime locations may come with higher land prices, increasing initial
investment.
❖ Competition: Locating in industrial clusters may increase competition for resources and
skilled labor.
❖ Regulatory Compliance: Different regions may have varying regulations and
environmental standards, requiring additional compliance efforts.
❖ Distance from Markets: Choosing a remote location may increase transportation costs and
lead times for delivering products to customers.
❖ Natural Disasters: Some regions are prone to natural disasters such as earthquakes, floods,
or hurricanes, posing risks to the plant's operations.
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2. Site location: involves selecting the specific land within a chosen geographical area where
the manufacturing facility will be built.

• Advantages
❖ Optimal Layout: Choosing the right site allows for efficient layout design, minimizing
material handling costs and optimizing workflow.
❖ Expansion Potential: Choosing a site with room for future expansion allows for scalability
and long-term growth.

• Disadvantages:
❖ Site Preparation Costs: Some sites may require significant preparation, such as land
clearing, leveling, or infrastructure development, adding to upfront expenses.

❖ Security Risks: Sites located in high-crime areas or prone to security threats may require
additional measures to ensure the safety of employees and assets.

9.2.1 MAIN FACTORS TO BE CONSIDERED FOR PLANT AND SITE

LOCATION
❖ Marketing area
❖ Raw material supply
❖ Transport facilities.
❖ Availability of labor
❖ Availability of utilities (water, fuel, power)
❖ Availability of suitable land
❖ Environmental impact, and effluent disposal: have an impact on a certain industry in a
particular place. It increases the cost or expenses associated with treating the trash
generated by the operation.
❖ Local community considerations
❖ Climate
❖ Political and strategic considerations
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9.2.2 SITE LOCATION SELECTED FOR N-OCTANE PRODUCTION

The process to produce n-octane from ethylene and iso-butane is set in a plant layout using horizontal arrangement because it is easiest
to construct and has less pipe racking, however, it is more.
The chosen site is in Saudi Arabia Specifically Yanbu This is due to the presence of the Yanbu refinery, which is a source of raw materials
(ethylene and iso-butane), moreover this is due to the presence of the Yanbu refinery, which is a source of raw materials (ethylene and
iso-butane), moreover the lowest cost in utilities, where the process includes a lot of utilities.

Figure 9-1 Site layout

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Figure 9-2:Plant location

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10 CONCLUSION AND RECOMMENDATIONS

• A plant with a capacity of nearly 200,000 ton/yr. with purity 99.99 % is investigated in this
project.
• Two recycle streams estimated in N-octane production process recycle streams are critical
for enhancing efficiency, reducing waste, and optimizing resource utilization.
• Zeolite catalyst is used in the reactor at temperature 200 °C that gives a conversion of
88.12% to produce N-octane.
• Aspen Hysys software was used for simulating flow sheet and cross-checking of hand
calculation of material, and energy balances.
• An economic analysis for this process was done, using CAPCOST excel spreadsheet, and
the feasibility study of this project does give successful results.
• The profitability analysis showed that the conventional plant has a discounted payback
period DPBP about two year and six months.
• Calculating power generation and consumption in this plant shows that this process is a
power consumption process.
• Yanbu city in Saudi Arabia was chosen as location for this plant as it contain 3 refinery
plants which make it easier to get the raw materials.
• 3107 Kg/h iso-butane and 2999 kg/h ethylene will produce 6105 kg /h n-octane.
• Further environmental investigation should be performed with the purpose of making this
process friendlier to the environment.
• It's important to handle n-octane and other hydrocarbons with care due to their flammable
nature.
• N-Octane is toxic to aquatic life and can pollute lakes, rivers, and streams. It can also
contaminate groundwater.
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REFERENCES

CHAPTER 1
1. Geeksforgeeks (2023). N-octane. Retrieved November 12 ,2023 , from
https://www.geeksforgeeks.org/octane-formula-structure-properties-uses-sample-
questions/

2. Chemical book (2023).(N-OCTANE)Product Description. . Retrieved November 12

,2023, from
https://www.chemicalbook.com/ChemicalProductProperty_US_CB2124951.aspx#:~:text
=N%2DOCTANE%20Property&text=Boiling%20point%3A,127%20%C2%B0C(lit.)

3. Pubchem (2023).Octane. Retrieved November 12 ,2023 ,from

https://pubchem.ncbi.nlm.nih.gov/compound/Octane

4. Edgar, G., & Midgley, T. (1929). Knock and Octane Number of Motor Fuels. Industrial &
Engineering Chemistry, 21(8), 755–759.

5. ASTM D2699 - Standard Test Method for Research Octane Number of Spark-Ignition
Engine Fuel.

6. ASTM D2700 - Standard Test Method for Motor Octane Number of Spark-Ignition Engine
Fuel.

7. Handbook of Petrochemicals and Processes by Robert A. Meyers, ed., Marcel

Dekker, 2005

8. n-Octane product page, Haltermann Carless, https://www.haltermann-

carless.com/products/n-octane.

9. n-Octane Wikipedia article, https://en.wikipedia.org/wiki/N-octane.

10. Food Oils and Fats: Processing Technologies by Dr. N.D. Arora, CRC Press, 2019.
157

11. Handbook of Pharmaceutical Excipients by Raymond C. Rowe, Paul J. Sheskey, and

Marian E. Quinn, Pharmaceutical Press, 2009.

12. Pharmaceutical Solvents by Marc Rogge, Wiley-Blackwell, 2016.

13. James G. Speight. The Chemistry and Technology of Petroleum (5th Edition). Marcel
Dekker, 2007.

14. James G. Speight. The Chemistry and Technology of Natural Gas (2nd Edition). Marcel
Dekker, 2011.

15. Bridgwater, A. V. (2012). Fast pyrolysis of biomass: a review of the fundamentals,

technologies and products. Renewable and Sustainable Energy Reviews, 16(8), 5708-5738.

16. Dry, M. C. (2002). The Fischer-Tropsch process: 1950-2000. Catalysis Today, 71(3-4),
227-247.

17. Hazards - Octane (weebly.com)

18. https://fastercapital.com/content/Octane--The-Fuel-that-Drives
theWorld.html#Environmental-Impacts-of-Octane-and-Alternative-Options

19. https://pubchem.ncbi.nlm.nih.gov/compound/Octane#section=Hazards-Summary

20. https://en.wikipedia.org/wiki/Isobutane

21. https://www.britannica.com/science/isobutane

22. James G. Speight. The Chemistry and Technology of Natural Gas (2nd Edition). Marcel
Dekker, 2011.

23. James G. Speight. The Chemistry and Technology of Petroleum (5th Edition). Marcel
Dekker, 2007.

24. .https://en.wikipedia.org/wiki/Ethylene

25. .https://pubchem.ncbi.nlm.nih.gov/compound/Ethylene

26. https://www.britannica.com/science/ethylene

27. Global N-octane Market Research Report 2020-2024 | Market Research Reports® Inc.
158

CHAPTER 2
1. Speight, J. G. (2014). The Chemistry and Technology of Petroleum (Fifth Edition). CRC
Press.

2. Gary, J. H., & Handwerk, G. E. (1984). Petroleum Refining: Technology and Economics
(2nd Edition). Marcel Dekker.

3. "Alkylation of Butanes with Olefins" by R.A. Sheldon, in "Applied Catalysis B:

Environmental" (2002), 34, 165-170.

4. "Fischer-Tropsch Synthesis: A Review" by G.A. Olah, A.E. Goeppert, and G.K.S. Prakash,
in "Journal of Catalysis" (2009), 265, 503-519.

5. "Comparison of Alkylation and Fischer-Tropsch Processes for n-Octane Production" by

S.K. Sadhukhan, A.K. Dutta, and J.C. Ghosh, in "Energy" (2014), 65, 275-281.

6. "Environmental Assessment of Alkylation and Fischer-Tropsch Processes for n-Octane

Production" by M.G. Rasul, N.A. Khan, and M.R. Othman, in "Journal of Cleaner
Production" (2012), 29-30, 15-22.

7. "Biomass to n-octane: A review of technologies and challenges" by J.C. Serrano-Ruiz et

al. (2019)1-10

8. "Production of n-octane from bio-oil via catalytic cracking" by H. Wang et al. (2014)
11-20

9. "Fermentative production of n-octane from renewable feedstocks" by Z.J. Zhang et al.

(2016)21-30

10. "Economic analysis of n-octane production from biomass" by M.R. Eden et al. (2015) 31-
40

11. "Environmental assessment of n-octane production from biomass" by S.R. Raheem et al.
(2017) 41-50

12. Analysis Synthesis and Design of Chemical Processes, Fourth Edition

159

CHAPTER 3 & 4
1. Yaws , Carl.Chemical properties handbook :physical , thermodynamic ,environmental
,transport , safety,and health related properties for organic and in organic chemicals / Carl
L .Yaws .

2. Richard M.Felder and Ronald W.Rousseau , Elementary Principies of Chemical Processes

(Third Edition) .

3. Analysis Synthesis and Design of Chemical Processes, Fourth Edition

CHAPTER 5
1. https://cheguide.com/double_pipe.html
2. https://processecology.com/articles/the-step-by-step-guide-double-pipe-heat-exchanger-
design
3. Coulson & Richardson’s , chemical engineering design (volume 6).

CHAPTER 6
1. Zeolite Molecular Sieve Catalyst for Adsorption of Vocs From Vehicles - China Zeolite
13X and Molecular Sieve 13X (made-in-china.com)
2. https://www.imarcgroup.com/ethylene-pricing-report
3. https://medium.com/intratec-products-blog/butane-price-saudi-arabia-q1-2023-
c812dc0c508f

CHAPTER 7
1. https://hsewatch.com/nfpa-diamond/
2. https://www.thomasnet.com/insights/10-types-of-ppe-that-should-be-on-your-essential-
list-for-a-safe-industrial-workplace-checklist/
3. https://cameochemicals.noaa.gov/chemical/1240
4. https://cameochemicals.noaa.gov/chemical/8655
5. https://cameochemicals.noaa.gov/chemical/8744
160

CHAPTER 8
1. Dale E. Seborg ,Thomas F. Edgar, Duncan A. Mellichamp and Francis J. Doyle III,
process dynamics and control (4th edition)

CHAPTER 9
1. Richard Turton and Richard C. Bailie , Analysis Synthesis, and Design of Chemical
Processes (Fourth Edition)
161

APPENDIX A: EQUIPMENT DESIGN

Figures

C1

C2
162

C3

C4
163

C5

C6
164

C7
165

Tables

T1

T2
166

T3

T4
167

APPENDIX B: SAFETY AND ENVIRONMENTAL

ASPECT.
168
169
170

SDS (SAFETY DATA SHEET) Links

SDS N-octane

https://www.bing.com/ck/a?!&&p=5f0d34c0c21a8961JmltdHM9MTcxNTM4NTYwMCZpZ3V
pZD0yNjQ1MjBhNi05ZDQ1LTY0MTYtMGJjMS0zMzQwOWMyZTY1YjImaW5zaWQ9NTE
4OA&ptn=3&ver=2&hsh=3&fclid=264520a6-9d45-6416-0bc1-
33409c2e65b2&psq=sds+safety+dat+a+sheet+bn+octane+&u=a1aHR0cHM6Ly93d3cuZmlzaG
Vyc2NpLmNvbS9zdG9yZS9tc2RzP3BhcnROdW1iZXI9QUMzOTY5MDEwMDAmcHJvZHVj
dERlc2NyaXB0aW9uPU4tT0NUQU5FJnZlbmRvcklkPVZOMDAwMzIxMTkmY291bnRyeUN
vZGU9VVMmbGFuZ3VhZ2U9ZW4&ntb=1

SDS Iso -butane

https://www.bing.com/ck/a?!&&p=73c30d514faed90cJmltdHM9MTcxNTM4NTYwMCZpZ3V
pZD0yNjQ1MjBhNi05ZDQ1LTY0MTYtMGJjMS0zMzQwOWMyZTY1YjImaW5zaWQ9NTE
4OQ&ptn=3&ver=2&hsh=3&fclid=264520a6-9d45-6416-0bc1-
33409c2e65b2&psq=sds+safety+dat+a+sheet+iso+butane+&u=a1aHR0cHM6Ly93d3cubGluZG
UtZ2FzLm5vL25vL2ltYWdlcy9Jc29idXRhbmVfUjYwMEFfMS4xJTIwRU5OT190Y202Mzkt
NTk4MDI3LnBkZg&ntb=1

SDS Ethylene

https://www.bing.com/ck/a?!&&p=f9e8c1b0e1296df3JmltdHM9MTcxNTM4NTYwMCZpZ3V
pZD0yNjQ1MjBhNi05ZDQ1LTY0MTYtMGJjMS0zMzQwOWMyZTY1YjImaW5zaWQ9NTI
xNA&ptn=3&ver=2&hsh=3&fclid=264520a6-9d45-6416-0bc1-
33409c2e65b2&psq=sds+safety+dat+a+sheet+ethylene+&u=a1aHR0cHM6Ly93d3cuY2hlbWlj
YWxib29rLmNvbS9tc2RzL0VUSFlMRU5FLmh0bQ&ntb=1