Gasification (eBook)

Front cover 1
copyright 5
Contents 6
Preface 8
COMPANION WEBSITE 10
TERMINOLOGY 10
ACKNOWLEDGMENTS 11
1. Introduction 12
1.1 HISTORICAL DEVELOPMENT OF GASIFICATION 12
1.2 GASIFICATION TODAY 16
2. The Thermodynamics of Gasification 20
2.1 REACTIONS 21
2.2 THERMODYNAMIC MODELING OF GASIFICATION 24
2.2.1 Basic Data 25
2.2.2 Equations 27
2.2.3 Variables 28
2.3 DEDUCTIONS FROM THE THERMODYNAMIC MODEL 28
2.3.1 Effect of Pressure 28
2.3.2 Effect of Temperature 30
2.3.3 Fuel Footprint 31
2.3.4 Surprises in Calculations 34
2.4 OPTIMIZING PROCESS CONDITIONS 34
2.4.1 Process Indicators 35
2.4.2 Optimum Operating Point 36
3. The Kinetics of Gasification and Reactor Theory 40
3.1 KINETICS 40
3.1.1 Devolatilization 41
3.1.2 Volatiles Combustion 42
3.1.3 Char Gasification 43
3.2 REACTOR THEORY 46
3.3 APPLICATIONS TO REACTOR DESIGN 49
3.3.1 Modeling 49
4. Feedstocks and Feedstock Characteristics 52
4.1 COALS AND COKE 52
4.1.1 Formation of Coal 53
4.1.2 Coal Analysis 53
4.1.3 Other Minerals in Coal 58
4.1.4 Other Properties 59
4.1.5 Ash Properties 60
4.1.6 Coke 64
4.1.7 Petroleum Coke 64
4.2 LIQUID AND GASEOUS FEEDSTOCKS 64
4.2.1 Refinery Residues 64
4.2.2 Other Liquid Feedstocks 74
4.2.3 Natural Gas 77
4.2.4 Other Gaseous Feedstocks 78
4.3 BIOMASS 78
4.3.1 Properties of Biomass 79
4.3.2 Black Liquor 81
4.3.3 Biomass Production 83
4.3.4 Development Potential 84
4.4 WASTES 87
4.4.1 Solid Waste 87
4.4.2 Liquid Wastes 89
5. Gasification Processes 96
5.1 MOVING- BED PROCESSES 98
5.1.1 The Lurgi Dry Ash Process 99
5.1.2 British Gas/ Lurgi ( BGL) Slagging Gasifier 105
5.1.3 Ruhr 100 108
5.2 FLUID- BED GASIFIERS 109
5.2.1 Common Issues 110
5.2.2 The Winkler Process 112
5.2.3 The High- Temperature Winkler ( HTW) Process 114
5.2.4 Circulating Fluid- Bed ( CFB) Processes 116
5.2.5 The KBR Transport Gasifier 116
5.2.6 Agglomerating Fluid- Bed Processes 118
5.2.7 Development Potential 119
5.3 ENTRAINED- FLOW GASIFIERS 120
5.3.1 General Considerations 124
5.3.2 The Koppers- Totzek Atmospheric Process 128
5.3.3 Shell Coal Gasification Process ( SCGP) and Prenflo Process 129
5.3.4 The Noell Process 131
5.3.5 The Texaco Process 133
5.3.6 The E- Gas Process 136
5.3.7 The CCP Gasifier 137
5.3.8 The EAGLE Gasifier 139
5.4 OIL GASIFICATION AND PARTIAL OXIDATION OF NATURAL GAS 139
5.4.1 The Texaco Gasification Process 140
5.4.2 The Shell Gasification Process ( SGP) 144
5.4.3 Lurgi’s Multipurpose Gasification Process ( MPG) 151
5.4.4 New Developments 153
5.4.5 Process Safety 157
5.5 BIOMASS GASIFICATION 158
5.5.1 Fluid- Bed Processes 159
5.5.2 Twin Fluid- Bed Steam Gasification 161
5.5.3 Pyrolysis Processes 164
5.5.4 Other Processes 166
5.6 GASIFICATION OF WASTES 166
5.6.1 Coal Gasifiers in Waste Service 167
5.6.2 Purpose Developed Processes 168
5.7 BLACK LIQUOR GASIFICATION 170
5.7.1 The Chemrec Process 170
5.7.2 MTCI "Pulse Enhanced" Steam Reformer 171
5.8 MISCELLANEOUS PROCESSES 172
5.8.1 In situ Gasification 172
5.8.2 Molten Iron Processes 173
5.8.3 Plasma Gasification 173
5.8.4 Hydrogasification 173
6. Practical Issues 182
6.1 EFFECT OF PRESSURE 182
6.2 PRESSURIZATION OF COAL 184
6.2.1 Dry- Coal Feeding with Lock Hoppers 184
6.2.2 Pumping Coal as a Coal- Water Slurry 188
6.2.3 Wet Lock Hoppers 190
6.2.4 Tall Hoppers for Pressurizing 191
6.2.5 Miscellaneous Methods of Pressurizing 193
6.3 COAL SIZING AND DRYING 194
6.3.1 Coal Sizing 194
6.3.2 Coal Drying 194
6.4 REACTOR DESIGN 195
6.4.1 Reactor Embodiment 195
6.4.2 Reactor Containment and Heat Loss 196
6.5 BURNERS 202
6.6 SYNTHESIS GAS COOLING 203
6.6.1 Quenching 204
6.6.2 Synthesis Gas Coolers 207
6.6.3 Syngas Cooling in Oil Service 208
6.7 PARTICULATE REMOVAL 211
6.7.1 Dry Solids Removal 211
6.7.2 Wet Solids Removal 212
6.8 PROCESS MEASUREMENT 212
6.8.1 Gasification Temperature Measurement 212
6.8.2 Temperature Control 215
6.8.3 Gas Analysis 215
6.9 TRACE COMPONENTS OF RAW SYNTHESIS GAS 219
6.9.1 Sulfur Compounds 219
6.9.2 Nitrogen Compounds 220
6.9.3 Chlorine Compounds 223
6.9.4 Unsaturated Hydrocarbons 223
6.9.5 Oxygen 223
6.9.6 Formic Acid 224
6.9.7 Carbon 224
6.9.8 Metal Carbonyls 225
6.9.9 Mercury 228
6.9.10 Arsenic 229
6.10 CHOICE OF OXIDANT 230
6.10.1 Effect of Oxidant on the Gasification Process 230
6.10.2 Equipment Sizing and Gas Flow Rate 232
6.10.3 Parasitic Power 233
6.10.4 Deductions 234
6.11 CORROSION ASPECTS 234
6.11.1 Sulfur 234
6.11.2 Hydrogen 235
6.11.3 Chlorides 235
6.11.4 Metal Dusting 236
7. Applications 242
7.1 CHEMICALS 242
7.1.1 Ammonia 243
7.1.2 Methanol 250
7.1.3 Hydrogen 254
7.1.4 Carbon Monoxide and Oxo- Alcohols 260
7.2 SYNFUELS 263
7.2.1 Gas to Liquids 265
7.2.2 SNG from Coal 269
7.3 POWER 270
7.3.1 Comparison with Combustion 271
7.3.2 State- of- the- Art IGCC 278
7.3.3 Advanced Cycles 281
7.3.4 Flue Gas Treatment 289
7.3.5 Miscellaneous 298
7.3.6 Energy Storage 298
8. Auxiliary Technologies 304
8.1 OXYGEN SUPPLY 304
8.1.1 Technologies 304
8.1.2 Pipeline and Other Supply Possibilities 308
8.2 SYNTHESIS GAS TREATING 309
8.2.1 Selection Criteria 309
8.2.2 Absorption Systems 311
8.2.3 Adsorption Systems 320
8.2.4 Membrane Systems 323
8.2.5 Further Developments 326
8.2.6 Biomass Syngas Treating 326
8.3 CO SHIFT 326
8.3.1 Clean Gas Shift 327
8.3.2 Raw Gas Shift 328
8.4 SULFUR RECOVERY 329
8.4.1 The Claus Process 329
8.4.2 Tail Gas Treatment 332
8.4.3 Integration in an IGCC 334
8.4.4 Sulfuric Acid 334
9. Economics, Environmental, and Safety Issues 340
9.1 ECONOMICS 340
9.2 ENVIRONMENTAL ISSUES 346
9.2.1 Gaseous Effluents 347
9.2.2 Greenhouse Gases 350
9.2.3 Liquid Effluents 355
9.2.4 Solid Effluents 356
9.2.5 Waste Gasification 358
9.3 SAFETY 358
9.3.1 Start- Up 359
9.3.2 Shutdown 359
9.3.3 Spontaneous Combustion 359
9.3.4 Toxic and Asphyxiating Materials 360
9.3.5 Oxygen 360
10. Gasification and the Future 366
Appendix A: Companion Website 370
Appendix B: Conversion Factors 372
Appendix C: Emissions Conversion Factors 378
Appendix D: Guidelines for Reporting Operating Statistics for Gasification Facilities 380
Appendix E: Basis for Calculations 384
Nomenclature 386
List of Names and Abbreviations 388
Index 392