1. Mamoon Asif || Zubia Saleem|| Mubeen Kamran
Project Supervisor: Dr. Arshad Hussain
Department of Chemical Engineering. SCME (NUST), Islamabad
Abstract
As Pakistan is moving deeper into the
clutches of energy and natural gas cri-
sis, it has become crucial to search for
new sources to meet our increasing de-
mands. Coal is believed to be the future
energy carrier for the world; however,
due to environmental hazards the pro-
duction of electricity from coal is not
being commercialized on a large scale.
Integrated Gasification Combined Cycle
(IGCC) process is the solution for this
problem. Lignite is the most abundant
coal present in Pakistan which has a
very lower heating value. To utilize the
full capacity of lignite, the coal-water
slurry feed is converted into Coal-CO2
Slurry by the PHICCOS Process. This
process increases the Net IGCC and Cold
Gas Efficiency by 15%. IGCC uses the Pre-
Combustion Technique to remove CO2
hence protecting the environment.
Motivation
 Coal is an alternative source for electricity
production and with igcc less harm is done
to the environment as copared to the con-
ventional gasification processes.
 Entrained Flow Gasification is Environmen-
tal Friendly.
 IGCC reduces the waste (clean and healthy
Pakistan)
Chemistry of Gasification
C + 0.5O2 →CO
C + H2O →CO + H2
C + 2H2 →CH4
CH4 +1.5O2 →CO + 2H2O
CO + H2O→CO2 + H2
CO + 0.5O2 →CO2
S + H2 →H2S
S + O2→SO2
CO + H2S →COS + H2
N2 + 3H2 →2 NH3
Selection Criteria
Entrained Flow Gasifier
Material Input
Coal-CO2 Slurry (kmol/ 10846.02
Oxygen Rich Stream 1677.63
Steam (kmol/hr) 524.63
Total 13048.28
Energy Input
Materials Energy (kcal)
Coal (CV) 3 x108
Enthalpy of steam in gasifier 2.735 x 106
Sensible Heat of CO2 3.35 x 107
Total Energy of the input Feed 3.36 x 108
Thermal Efficiency 77%
Cold Gas Efficiency 74.4%
Hot Gas Efficiency 97.2%
Syngas Composition
Composition Mol %
CO 6.68
CO2 32.3
O2 13.7
N2 0.448
H2 38.5
CH4 1.52
H2S 0.025
COS 0.1362
SO2 0.17
NH3 0.2605
H2O 5.86
Total 100
Selected Processes
SECTION UNIT KEY FOCUS METHOD ASSISTANCE
Entrained Flow Gasifi-
er
Process To convert the Coal-CO2 Slurry into
syngas and slag
Gasification Flame Fired
Air Separation Unit Operation To separate air into N2 and O2 to ensure
supply into Entrained Flow Gasifier and
Combustor
Cryogenic Distillation Carbon Molecular Sieves
Shift Conversion Process Convert CO to CO2 and maximum hy-
drogen production
Catalytic Shift Conversion Iron Oxide Catalyst,
Copper Oxide Catalyst, Steam
CO2 and H2 S Removal
(AGR)
Process To reduce concentration of CO2 and
H2S is also removed.
Absorption SELEXOL Solvent
COS Hydrolysis Process Conversion of COS to H2S and CO2 Catalytic Bed Reactor Catalyst
(Nickel Based)
Combustor Process To combust the clean syngas in order
to run the gas turbine
Complete Combustion Clean Syngas as fuel
Process Flow Diagram
Results & Analysis
Cost Estimation
The major advantages of this project scheme
are the efficient production of power using
environmentally harm-free processes by re-
ducing the emissions of sulfur dioxide, par-
ticulates and carbon dioxide and efficient
utilization of recovered heat from syngas
cooling system and minimal waste produc-
tion as the by-products are marketable.
Conclusions
References
1) SIMULATION AND ECONOMIC EVALUATION OF COAL
GASIFICATION WITH SETS REFORMING PROCESS FOR POW-
ER PRODUCTION by Zachary Hoffman
2) Technical Documentation: Integrated Gasification Com-
bined Cycle Systems (IGCC) with Carbon Capture and Storage
(CCS) Authors Edward S. Rubin, Michael B. Berkenpas, H.
Christopher Frey, Chao Chen, Sean T. McCoy, and Constance
EQUIPMENT COST (K$)
Entrained Flow Gasifier 23000.11
ASU & Compressor 4000.68
HTSC 27.4
LTSC 13.682
AGR (Absorber) 4064
Convective Cooler 9661.7
Process Condensate Han-
dling Section
16708.05
Energy Output
Materials Energy (Kcal)
Syngas (CV) 250 x 106
Enthalpy of H2 O 8.81 x 106
Sensible heat of Syngas 67.7 x 106
Heat Loss 9.49
Total Output of Energy (KW) 3.36 x 108
Material Output
Slag ((kmol/hr) 170.196
Syngas (kmol/hr) 12877.844
Total 13048.04
•Feed rate of 10,846 kmol/hr (80%-20%)
Coal-CO2 slurry results in a production
of 267 mw Power.
•The CO2 that has been sequestered from
the process is used in the preparation of
CO2-Coal Slurry hence optimizing the
process.
•Pre-Combustion technique is more effi-
cient than Post-combustion since CO2 is
at high partial pressure and is easily re-
movable.
•Entrained flow gasifier is the ideal
choice for this gasification since the
temperature is above ash slagging tem-
perature and proper mechanism is avail-
able for ash removal. Moreover, it can
gasify all types of coal regardless of
coal rank, caking characteristics or
coal fines’ amount.
 Net Efficiency of the plant calculated
is about 66% which is enough to meet
the desired electricity needs.
 Capital cost is high but due to the
modifications done and also less mar-
ginal cost the process becomes feasible.
Power Production Using Syngas From Coal-Water Slurry
Calorifiic value of coal
HHV (kJ/kg) 14551.161
LHV (kJ/kg) 12689.798
Net Plant Effi-
ciency 66%