COAL GASIFICATION

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COAL GASIFICATION GASIFICATION ONLY REASONABLE
WHEN PLANT IS INTEGRATED SOME PROCESSES ARE
COMMERCIAL H2S REMOVAL BY THE CLAUS
PROCESS H2S O2 H2O SO2 H2S SO2 S
H2O
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Energy Content Summary.
Type Btu/SCF
Producer Gas 90-120
Water Gas 341
Low-Btu 150
Intermediate-Btu 260-300
SNG 950
Methane 1054
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Probable Uses.

• Low-Btu gas
• Local electrical power generation
• Cannot be used for home or commercial heating
• Intermediate-Btu gas
• Electrical power generation
• Feed stock for chemicals
• Town gas
• High-Btu gas. Same as natural gas

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Selection of a Gasifier

• Type of bed
• Operating pressure
• Slagging, non-slagging
• Lurgi (fixed bed, high P, non-slagging)
• Koppers-Totzek (entrained bed, low P,
• slagging)
• Wellman-Galusha (fixed, low P, non-slagging)
• Winkler (fluidized, low P, non-slagging)

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CO2
25,303 TPD _at_ 8,920 Btu/lb FEED COAL
H2SCO2
SULFUR PLANT
ELEMENTAL SULFUR 128 LTPD
GAS LIQUOR
COAL PREPARATION
OXYGEN-BLOWN COAL GASIFIERS
SCRUBBING AND COOLING
CRUDE GAS SHIFT CONVERSION H2OCOH2CO2
RECTISOL GAS PURIFICATION
COMPRESSION AND DEHYDRATION
METHANATION 3H2COCH4H2O
TARRY GAS LIQUOR
OXYGEN
PIPELINE GAS 290 MMSCFD _at_ 950 Btu/Scf
OILY GAS LIQUOR
N2
STEAM
GAS LIQUOR SEPARATION AND EFFLUENT WATER TREATMENT
STEAM AND POWER PLANT
COAL FINES
OXYGEN PLANT
RECLAIMED WATER TO PLANT USE
NAPHTHA
ELECTRIC POWER TO PLANT USE
AIR
COAL TAR
TOTAL LIQUIDS 8940 BBLS/day
COAL OIL
PHENOLS
155 tons/day
AMMONIA
Figure 7-6. Pipeline gas from coal via Lurgi
pressure gasification.
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Figure 7-11. The Texaco gasifier (also Shell,
Eastman)
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System for In-Situ Gasification of Coal
From Wiser, 2000
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Financial Dilemma

• Synthetic natural gas cost
• - gt10.00/106 Btu
• Investment
• - 75 x 1012 Btu/year plant, 30 year life
• - 8 billion
• Benchmark is cost of oil and gas energy sources
• - Need a floor on the price of energy over a
  long time frame