Soran University

Faculty of Engineering- Chemical Department

Membrane Filtration Separation

Supervisor:_ mr. Ali Husain

Prepared by:_ Abdulla omer

Membrane filtration separation:

Membrane filtration process is a physical separation method characterized by the ability to

separate molecules of different sizes and characteristics. Its driving force is the difference in
pressure between the two sides of a special membrane. Membrane technology enables you to
bring down overall production costs, and boost product quality at the same time. Membrane
filtration can be a very efficient and economical way of separating components that are
suspended or dissolved in a liquid. The membrane is a physical barrier that allows certain
compounds to pass through, depending on their physical and/or chemical properties. Membranes
commonly consist of a porous support layer with a thin dense layer on top that forms the actual
membrane.also two types of filtration process are possible :

1- Cross-flow filtration
2- Dead-end filtration

Cross-flow filtration VS Dead-end filtration:

Membrane filtration can be either dead-end filtration or cross-flow filtration.Cross-flow
filtration provides significant built-in advantages over dead-end filtration.Because the liquids
being processed flow continuously across the membrane, there is no filter cake that can lead to
fouling and uneven flow.This makes it possible to operate a continuous, automated filtration
process that results in a consistent, controllable product quality. No filter aids are needed, and the
membranes have an extended lifetime. Almost all industrial membrane filtration is carried out as
cross-flow filtration, where the liquid being filtered flows parallel to the membrane at high
velocity and under pressure.

Fig-1- Cross-flow filtration VS Dead-end filtration

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Main parameters of filtration:
"the filtrate flow rate QF is the flow crossing the membrane, expressed in m3/s or in lit/hour
(l/h)." the permeate flux J is equal to QF/S, permeate flow per unit area of membrane, generally
expressed in l/hm2. "the mean trans membrane pressure (ptm) is given by
Ptm= (pa+pr)/2-pf
where pa is feed pressure, pr retentate pressure at membrane exit and the filtrate pressure. "the
sieving coefficient S of membrane is given by :

S=Cf/Cr’

where CF is the permeate concentration and Cr that of retentate. the rejection rate is S=1-S; it is
complete if S=0 or R=l. For a membrane with uniform pores, there is no rejection (R=O) for
solutes with diameter smaller than pores diameter and R will be equal to 1 for solutes with larger
diameters than pores. In fact, since pores are not uniform, it frequently happens that solutes will
only pass through larger pores and their rejection will be partial, with R<l.
Membranes are characterized by their hydraulic permeability Lp= J /ptm where J is the pure
water flux. Permeability units are m/(Pa s) or 1/(hm2 bar). This permeability depends upon
diameter and pores density as well as membrane thickness. Membrane resistance Rm (m-1) is
given by Rm = and, unlike hydraulic permeability, depends upon fluid viscosity.

types of membrane filtration:

There are four commonly accepted categories of membranes. These are defined on the basis of
the size of material they are required to
separate from the feed liquid. The membrane types are known as

1- reverse osmosis
2- nano filtration
3- ultrafiltration
4- microfiltration

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1-Reverse Osmos

Overview: Fig-2-RO Membrane

Reverse Osmosis Plant is widely used for removal of dissolve chemical impurities from brackish
& seawater. Reverse osmosis is the process of forcing a solvent from a region of high dissolve
solids concentration through a membrane to a region of low dissolve solids concentration by
applying a pressure in excess of the osmotic pressure. The semi permeable membranes used for
reverse osmosis have a dense polymer barrier layer in which separation takes place.
Shubham RO Plants are designed for a variety of industrial & commercial applications requiring
high quality equipment with a fast delivery and competitive price. These pre-engineered, pre-
assembled and factory tested units minimize installation and start-up time. With simple utility
connections and easy to set up controls, the unit is ready for quick on-line service. The control
system is an advanced microprocessor based system that is very easy to use.
Shubham RO Plants are available in flow rates from 0.25 M3/hr. to 100 M3/hr. Using high
quality 4 and 8 inch semipermeable membrane and equipments for variety of applications.

Working Principal:
Reverse osmosis is water purification process in which pre-treated & filtered water is connected
to the high-pressure pump where pressure is developed and fed to the RO membranes. Reverse
Osmosis membranes work on the Cross flow Filtration method where the salts get rejected
partially and deliver pure water. Purified water is referred to as product and waste water is
referred to as concentrate or reject. The percent of water delivered as product is called the
recovery. The ratio of recovery& output parameters depend upon the feed water quality, type of
membrane ,temperature and total RO unit design considerations.

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 Table -1-Technical Specifications:

Salient features:

• TFC RO Membranes ensure optimum water quality

• High pressure 316 stainless steel vertical multistage feed pump
• ASME Code FRP, RO pressure vessels with pressure relief protection
• UPVC low pressure feed, product and reject piping, 316L stainless steel high pressure piping
• Epoxy coated carbon steel / SS frames
• Dry contacts are provided for chemical feed, pre-treatment equipment, storage tank levels, and
pressure switches
• All alarm and shut down conditions are indicated on the control interface.

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Advantages:

• User-friendly programmable controls

• High quality components ensure continuous, reliable operation
• Pre-engineered systems mean easy installation
• Clean-in-place connections maximize system availability
• Compact footprint saves valuable floor space
• Quick equipment delivery keeps project moving fast
• Easy to install and operate.
• Produces high quality Water
• Variety of cost effective standard models.

Application:

• Boiler water Treatment

• Cooling Tower Water Treatment
• Process Water
• Drinking Water
• Horticulture for high end crop
• Dialysis
• Laboratories
• Water For injection (WFI)

• Water for electrical conductor circuits

• Wastewater recycling
• Zero Liquid discharge system

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2-Ultra filtration:

Fig-3- Ultra filtration membrane

Overview:
Ultrafiltration (UF) is an important purification technology used for the production of high-
purity water in the many industries. When strategically combined with other purification
technologies in a complete water & Wastewater system. UF membranes used to remove high
molecular-weight substances, colloidal materials, silt, turbidity, organic / inorganic polymeric
molecules, algae, particulate matters, suspended solids and all microorganisms from Water &
Wastewater. Shubham UF Plants are designed for a variety of industrial & commercial
applications requiring high quality equipment with a fast delivery and competitive price. These
pre-engineered, pre-assembled and factory tested units minimize installation and start-up time.
With simple utility connections and easy to set up controls, the unit is ready for quick on-line
service. The control system is an advanced microprocessor based system that is very easy to use.
Shubham UF Plants are available in flow rates from 0.25 M3/hr. to 100 M3/hr. Using high
quality Hollow fiber UF membrane and equipment for variety of applications.

Working Principle :
Ultra filtration is a unique pressure-driven physical separation process in which the water is
passed through porous (partially permeable) membranes with pore sizes in the range of 0.1 to
0.01 micron .These membranes are in the form of long hollow fibers. The result is high pure
water free from physical and biological contaminations.
Ultra filtration is not fundamentally different from microfiltration or nano filtration, except in
terms of the size of the molecules it retains. Ultra filtration is applied in cross-flow or dead-end
mode and separation in ultra-filtration undergoes concentration polarization.

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 table-2-Technical Specification:

Salient Features

Salient Features:
• Low fouling Hydrophilic UF membrane
• Excellent filter performance with high flux
• High removal efficiency of bacteria and viruses
• Periodically back washed and air scoured for consistent performance
• Simple, vertical, modular design allows low cost, compact systems
• Fully automated control system for backwashing process
• Advanced custom designed Control Cubicle
• Stainless / carbon steel equipment frame
• Permeate, back pulse pumps, membrane aeration blowers and associated valving mounted on
equipment frame
• Control panel with standard PLC and HMI interface mounted on equipment frame.
• High end electrical actuated operating valves.

• All alarm and shut down conditions are indicated on the control interface.

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Advantages:

• User-friendly programmable controls

• High quality components ensure continuous, reliable operation
• Pre-engineered & factory tested systems mean easy installation
• CEB (Chemical enhance backwash) connections maximize system availability
• Compact footprint saves valuable floor space
• Quick equipment delivery keeps project moving fast
• Produces high quality Water.
• Easily integrated into an existing facility
• Requires minimal operator supervision
• Most comprehensive cleaning capability ensures peak system performance
• Ideal for direct reuse

Application:

• Pre & Post Treatment for RO Plant

• Cooling Tower make up & blow down Water Treatment
• Drinking Water
• Water for injection (WFI)
• Wastewater recycling
• Zero Liquid Discharge system
• Tertiary Treatment
• River Water Treatment
• Colloidal silica removal
• Heavy metal removal

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3-Nano filtration membrane:

fig- 4-nanofiltration membrane

Overview:
Nanofiltration is a separation process characterized by organic, thin-film composite membranes
with a pore size range of 0.1 to 10nm. Unlike reverse osmosis (RO) membranes, which reject all
solutes, NF membranes can operate at lower pressures and offer selective solute rejection based
on both size and charge.

Advantages:

 There are no chemicals that are used, and that means that no chemicals will be disposed of to
the environment.
 Viruses, organic elements, and valence ions are removed from the hard water.
 It is an effective way of softening the hard water.
 The membrane has very tiny holes therefore ,most molecules cannot go through.

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Technical features:
1- Filled membrane element which adopts imported organic membrane, combined with the
technology requirements and user specific needs and choose different configurations of film
form, to ensure that the sBSWtem of different membrane element intercept performance,
membrane flux and membrane of a complete set of stability and reliability of the sBSWtem
operation.
2-With low operating pressure, the filter membrane sBSWtem can realize the desalination and
concentration of materials, and the production cycle is short, the desalination is relatively
complete, the products are high purity and good quality stability.
3-According to the specific needs of customers, the membrane components can be recovered
through the liquid through liquid, and the membrane elements can be restored to the best
performance of the membrane elements through professional cleaning, and fully realize the
economic performance of the membrane equipment.
4-Cardiac process remain the state of the normal temperature, and no phase transition process,
the effective components in material without any adverse effects, especially suitable for the
processing of heat sensitive material,
5-Due to the absence of phase change in the sBSWtem process, the sBSWtem is alwaBSW in
constant temperature thus the energy consumption is low and the running cost is low.
6-Has high degree of process integration, rational layout, to realize automatic control, the
important process parameters on-line monitoring.

Applications:
Nanofiltration membranes are a relatively recent development, and offer greater selectivity of
ions vs. reverse osmosis membranes that reject all ion species in a feed stream. This unique
characteristic provides flexibility in separation process development that can greatly impact
performance and profitability, especially for industrial applications .Here are some common
applications of Synder’s NF membrane technology:

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 Dairy:
1-Lactose and whey demineralization in dairy processing
2-Lactose and whey concentration

Industrial/Waste water Treatment:

1- Removal of natural organic matter in water and wastewater treatment
2- Reduction of hardness in water purification
3- Sulfate removal from seawater and chemical processes
4- Desalting of process streams in various industries

4-Microfiltration membrane:

Fig-5-microfiltration membrane

Overview:

Microfiltration is a low pressure separation process utilizing membranes with very open pore
structures. Microfiltration filters can be made with both organic materials, such as polymer based
membranes, as well as inorganic materials, such as ceramic or stainless steel. In selecting the
appropriate membrane, spiral-wound polymeric microfiltration filters are often the starting point
for consideration, based on spiral MF’s balance of durability, membrane area per unit, and
significantly lower membrane unit cost, and equipment capital cost vs. ceramic and stainless
options.

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 How does MF work?:
MF Physicallyseparate solids from liquid streams based on the principle of size- exclusion. As a feed
stream is passed through the MF membrane, any solids that are too large to pass through the membrane's
pores are retained, while any liquid or small particles are permitted to flow through. In either MF, the
portion of the feed stream that has passed through the filter membrane is referred to as the filtrate or
permeate, while the remainder is known as the retentate. Depending upon the industrial application at
hand, the filtrate and/or retentate may each be directed to other systems, as appropriate, for waste
treatment, or purification through RO.

Advantages:
1-Low operating pressure required
2- Low energy consumption for semi dead-end set-up,
3- filtration or reverse osmosis;
4- Few manual actions required;
5-Relatively cheap;
6- No energy-consuming phase transfer needed, such
7- evaporation techniques
8- Quality of the produced permeate is not determined by the management.

Applications:
Microfiltration is a physical separation process that removes contaminants such as suspended
solids, fats, and microbes from process fluids. Microfiltration may also be used in combination
with other membrane technologies such as reverse osmosis, nanofiltration, and ultrafiltration.
Common applications of Synder’s MF membrane technology include:

Dairy:
 Fat / microbial removal in Whey Protein Concentrate / Isolate
 Casein / Whey fractionation
 Clarification of fermentation broths
 Microbial removal, clarification

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 Food/Beverage:
 Plant extract clarification
 Gelatin clarification
 Wine clarification
 Corn wet milling
Industrial/Waste water Treatment
 Industrial process waste water treatment

Table-3-comparision between types of membrane filtration

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Referinces:

1-van der Bruggen B, Vandecasteela C, van Gestel T, Doyen W, Leysen R (2003) A review of
pressure driven membrane processes in wastewater treatment and drinking water production.
Environ Prog 22:46–56Google Scholar

2-Eykamp W (1995) Chapter 1: microfiltration and ultrafiltration. In: Noble RD, Stern SA (ed)
Membrane separation technology. Principles and application. Elsevier Science B.V 1–43Google
Scholar

3-Reneker DH, Chun I (1996) Nano metre diameter fibres of polymer, produced by electros
pinning. Nanotechnology 7:216–223Google Scholar

4-Bonnélye V., Guey L., Del Castillo J., Desalination, Volume 222, Issues 1-3, 1 March 2008,
Pages 59-65, 2008

5-EIPPCB, Reference Document on BAT in Common Waste Water and Waste Gas Treatment /
Management Systems in the Chemical Sector, draft February 2009 (revision upon release)

6-Mulder M.,Basic Principles of Membrane Technology, Kluwer Academic Publishers,

Dordrecht (NL), 1996.

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