Introduction ................................................... ix
1 The Nature of Coal ........................................... 1
The Geologic Origin of Coal .................................. 1
Coal Analysis and Classification ............................. 2
Coal Rank .................................................... 4
Ash Thermal Properties ....................................... 5
Coal as a Porous Material .................................... 9
Spontaneous Combustion ...................................... 10
Reserves, Resources, and Production ......................... 11
2 Non-gasification Uses of Coal ............................... 17
Home Heating and Cooking vs. Industrial Use ................. 17
Coal Combustion Pollutants .................................. 17
Pulverized Coal Combustion .................................. 19
Supercritical Pulverized Coal Combustion .................... 20
Carbon Capture with Pulverized Coal Combustion Plants ....... 21
Oxy-combustion .............................................. 24
Sargas ...................................................... 27
Coal-to-liquids ............................................. 28
3 Gasification Fundamentals ................................... 35
Process Goals ............................................... 35
Devolatization .............................................. 36
Reactions with Oxygen ....................................... 38
Char Reactions .............................................. 38
Additional Gas Phase Reactions .............................. 39
Slagging .................................................... 39
Balancing Coal, Oxygen and Water Feeds ...................... 39
Air Versus Oxygen Feed ...................................... 41
Estimating Syngas Composition from Equilibrium
Calculations ................................................ 41
Reaction Rates .............................................. 46
Fluidization Regimes ........................................ 64
Computational Fluid Dynamic Models .......................... 67
In Summary .................................................. 68
4 Gasifiers ................................................... 73
Overview .................................................... 73
Moving Bed Gasifiers: The Lurgi Gasifier .................... 73
BGL Gasifier ................................................ 75
Fluidized Bed Gasifiers: The Winkler Gasifier ............... 77
High Temperature Winkler Gasifier ........................... 79
U-Gas Gasifier .............................................. 79
Foster-Wheeler Partial Gasifier ............................. 79
KBR Transport Gasifier ...................................... 80
Entrained Flow Gasifiers: The GE Gasifier ................... 83
ConocoPhillips E-Gas Gasifier ............................... 88
Shell Gasifier .............................................. 90
Siemens Gasifier ............................................ 91
Mitsubishi Heavy Industries (MHI) Gasifier .................. 92
Pratt and Whitney Rocketdyne (PWR) Gasifier ................. 93
Less Conventional Gasifiers: The Alter NRG Plasma
Gasification System ......................................... 96
5 Underground Coal Gasification .............................. 101
Underground Gasification Concept ........................... 101
Motivation ................................................. 102
Connections between Injection and Production Wells ......... 102
Process Control and Modeling ............................... 103
Water Contamination ........................................ 107
UCG-recoverable Coal ....................................... 108
GasTech Process and Economic Study ......................... 108
6 Sulfur Recovery ............................................ 113
Coal Combustion ............................................ 113
Sulfur Compounds in Syngas ................................. 114
COS Hydrolysis ............................................. 114
Water Quench/Water Condensation ............................ 115
Acid Gas Removal Processes ................................. 116
Physical Solvent: Rectisol Process ......................... 117
Physical Solvent: Selexol .................................. 122
Chemical Solvents: Amines .................................. 124
Chemical Solvents: Benfield Process ........................ 126
Chemical Solvents: Aqueous Ammonia ......................... 127
Solid Adsorbents for Sulfur Removal ........................ 128
Elemental Sulfur: Claus Process ............................ 130
Shell Claus Offgas Treatment (SCOT) Process ................ 131
Sulfuric and Phosphoric Acid ............................... 132
Co-sequestration of CO2 and H2S ............................ 134
7 Hydrogen Production and Integrated Gasification Combined
Cycle (IGCC) ............................................... 137
Need for Increasing H2 Content ............................. 137
Water Gas Shift in the Catalytic Temperature Range ......... 138
Hydrogen for Ammonia Synthesis ............................. 139
Iron-Based HT Shift Catalyst ............................... 140
LT Shift Catalyst .......................................... 142
Sour Gas Shift ............................................. 142
Steam-Iron Process ......................................... 143
Hydrogen for Ammonia Synthesis: Removal of Residual
Impurities ................................................. 145
Dehydration ................................................ 146
Hydrogen for Proton Exchange Membrane Fuel Cells ........... 146
Hydrogen for Petroleum Refining ............................ 148
Combined cycle plants for power production, NGCC and
IGCC ....................................................... 149
Natural Gas Combined Cycle (NGCC) .......................... 151
Integrated Gasification Combined Cycle (IGCC) .............. 152
Combining IGCC and Oxy-Combustion .......................... 154
Methanol, SNG, and Fischer-Tropsch Synthesis ............... 155
8 Hydrogen Adsorption and Storage ............................ 157
Xin Hu, Maohong Fan, Brian Francis Towler, Maciej Radosz,
David A. Bell, Ovid Augustus Plumb
Introduction ............................................... 157
Physisorption of Hydrogen .................................. 158
Chemisorption of Hydrogen .................................. 210
Hydrogen Storage in Pure And Reduced Microporous and
Mesoporous Ti Oxides ....................................... 230
9 Mercury Removal ............................................ 247
Rodolfo Monterroso, Maohong Fan, Morris Argyle
Introduction ............................................... 248
Mercury Species in Coal Combustion ......................... 250
Summary of Technologies for Mercury Removal ................ 252
Flue Gas Components that Affect Mercury Sorption ........... 282
Summary .................................................... 288
10 CO2 Sorption ............................................... 293
Soonchul Kwon, Maohong Fan, Herbert F.M. DaCosta,
Armistead G. Russell, Kathryn A. Berchtold, Manvendra
K. Dubey
Introduction ............................................... 293
Sorption-based CO2 Separation Processes .................... 296
Adsorbent Performance for CO2 Capture ...................... 301
CO2 Capture Development Strategies ......................... 333
11 Ammonia and Derivatives .................................... 341
Historical Background ...................................... 341
Feedstocks for Ammonia Synthesis ........................... 342
Ammonia Synthesis Equilibria and the Synthesis Loop ........ 342
Ammonia Synthesis Catalysts ................................ 344
Ammonia Synthesis Kinetics ................................. 345
Ammonia as Nitrogen Fertilizer ............................. 347
Ammonia as a Transportation Fuel ........................... 348
Urea ....................................................... 348
Nitric Acid and Ammonium Nitrate ........................... 349
Future of Nitrogen Fertilizers ............................. 350
12 Methanol and Derivatives ................................... 353
Reaction Chemistry and Catalysts ........................... 353
Methanol Synthesis Equilibria .............................. 354
Methanol Synthesis Flowsheet ............................... 356
Methanol Synthesis Kinetics ................................ 357
Methanol as a Transportation Fuel .......................... 359
Dimethyl Ether ............................................. 359
Two Pot Synthesis of DME ................................... 360
One Pot Synthesis of DME ................................... 361
DME to Hydrocarbons: ExxonMobil MTG Process ................ 365
Methanol to Hydrocarbons: UOP/HYDRO MTO Process ............ 368
Methanol and DME to Hydrocarbons: Future Prospects ......... 370
13 Substitute Natural Gas and Fischer-Tropsch Synthesis ....... 373
Overview ................................................... 373
Substitute Natural Gas ..................................... 373
SNG Processes .............................................. 375
Competition Between Coal Gasification and Natural Gas ...... 377
SNG as a Carrier of Coal Energy ............................ 378
SNG Versus Synthetic Liquid Hydrocarbons ................... 378
Fischer-Tropsch History .................................... 379
Fischer-Tropsch Chemistry .................................. 379
FT reactor design .......................................... 381
Refining Fischer-Tropsch Fluids ............................ 385
FT Economics ............................................... 389
Index ......................................................... 393
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