Scribd
Upload
31 views12 pages

Group 2 Presentation

The document presents a presentation on Material and Energy Balance for ACCE 151, submitted to S.M. Fazle Rabbi at BSMRSTU. It includes calculations for combustion processes involving natural gas and coal, detailing the theoretical and actual air-fuel ratios and flue gas compositions. Group members are listed, and specific problems related to combustion efficiency and air requirements are solved.

Uploaded by

Tulmi Rajbanshi
Copyright
© © All Rights Reserved
We take content rights seriously. If you suspect this is your content, claim it here.
Available Formats
Download as PDF, TXT or read online on Scribd
31 views12 pages

Group 2 Presentation

The document presents a presentation on Material and Energy Balance for ACCE 151, submitted to S.M. Fazle Rabbi at BSMRSTU. It includes calculations for combustion processes involving natural gas and coal, detailing the theoretical and actual air-fuel ratios and flue gas compositions. Group members are listed, and specific problems related to combustion efficiency and air requirements are solved.

Uploaded by

Tulmi Rajbanshi
Copyright
© © All Rights Reserved
We take content rights seriously. If you suspect this is your content, claim it here.
Available Formats
Download as PDF, TXT or read online on Scribd
You are on page 1/ 12

(B S M R S T U)

PRESENTATION ON
ACCE 151: Material and Energy Balance

Submitted to:
S.M. FAZLE RABBI
Lecturer, Department of ACCE
BSMRSTU, Gopalganj

1
Group Members

MD. RASHEDUZZAMAN NUR HIMEL HASAN


ID NO 21ACE009 ID NO 21ACE013

TULMI RAJBANSHI MD FAHMID ISLAM


ID NO 21ACE010 ID NO 21ACE014

NIKHILESH BHOWMICK MD. JAWED KABIR


ID NO 21ACE011 ID NO 21ACE015

MD. ALI AREMAN TOOHA MD. ABU HASAN


ID NO 21ACE012 ID NO 21ACE016

2
Problem 3: To ensure complete combustion, 20 percent excess air is supplied to a
furnace burning natural gas. The gas composition (by volume) is methane 95 percent,
ethane 5 percent. Calculate the moles of air required per mole of fuel.

Solution :

(95%) CH4+ 2O2 CO2 + 2H2O

Theoretical required to burn =

= 190 mole O2

(5%) C2H6+ O2 2CO2 + 3H2O

Theoretical O2 required to burn C2H6 =

= 17.5 mole O2

3
Total theoretical O2 required = (190 +17.5) mole O2
= 207.5 mole O2

Theoretical air required =

= 987.5 mole air

 (moles air)fed required = 1185.24

4
5
Problem 4: A coal with dry, ash-free composition of 0.87 C, 0.09 H2 , 0.02 S and 0.02 O2
is burned with 25% excess air. The as-fired ash and moisture contents are 6% and 4%,
respectively.
(a) What are the stoichiometric and actual air-fuel ratios?
(b) What are the flue gas composition ?

Solution : (a)

Basis: 100 kg coal

Therefore, Moisture= 100  4% = 4 Kg


Ash content = 100  6% = 6 Kg

Ash and moisture free coal = 100-(6+4) = 90 Kg

Amount of carbon = 90  0.87 = 78.3 Kg; C + O2 CO2


Amount of hydrogen = 90  0.03 = 8.1 Kg; 2H2+ O2 H2O
Amount of sulfur = 90  0.02 = 1.8 Kg; S+ O2 SO2
Amount of oxygen = 90  0.02 = 1.8 Kg;

6
Theoretically, O2 required for 100 Kg = (208.8 + 64.8 + 1.8 – 1.8) = 273.6 Kg

 Theoretically, air required =

= 1190.16 Kg air

 Stoichiometric air to fuel ratio = 1190.16 : 100


= 11.9 : 1

7
 Actual air to fuel ratio = 1487.7 : 100
= 14.877 : 1
= 14.88 : 1

8
Solution : (b)

Coal CO2 (q1)


SO2(q2)
ash(q3) Flue gas
25% excess air H2O(q4)
(N2+O2) N2(q6)
O2(q5)

As information given, ash in flue gas, q3 = 100  6% = 6 Kg

For complete combustion, calculations:-


Form (a), amount of C = 78.3 Kg
 CO2 in flue gas, q1 = 78.3  = 287.1 Kg

Form (a), amount of S = 1.8 Kg


 SO2 in flue gas, q2 = 1.8  = 3.6 Kg

9
Form (a), amount of H = 8.1 Kg
 H2O in flue gas, q4 = (8.1  ) + 4  Form (a), Moisture of coal 4 Kg 
= 76.9 Kg

Form (a), air fed = 1487.7 Kg

 N2 fed = N2 in flue gas, q6 =

=1376.53 Kg N2
From (a),
theoretical O2 required = 273.6 Kg O2

 O2 fed =

= 342.17 Kg O2

O2 in flue gas, q5 = (342.17 – 273.6) Kg O2


= 68.57 Kg O2

10
Calculating composition of flue gas

Component Amount (Kg) in flue gas Composition in flue gas


CO2 287.1 0.158
SO2 3.6 0.002
ash 6 0.003
H2O 76.9 0.042
O2 68.57 0.038
N2 1376.53 0.757
Total = 1818.7

11
12

You might also like