Page 13 - Biomass Gasification, Pyrolysis And Torrefaction Practical Design and Theory

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9.4 Effect of Operating Parameters on SCW Gasification 327
9.4.1 Reactor Temperature 327
9.4.2 Catalysts 329
9.4.3 Residence Time 330
9.4.4 Solid Concentration in Feedstock 330
9.4.5 Heating Rate 331
9.4.6 Feed Particle Size 331
9.4.7 Pressure 333
9.4.8 Reactor Type 333
9.5 Application of Biomass Conversion in SCWG 333
9.5.1 Energy Conversion 334
9.5.2 Waste Remediation 335
9.5.3 Chemical Production 335
9.6 Reaction Kinetics 336
9.7 Reactor Design 337
9.7.1 Reactor Temperature 337
9.7.2 Catalyst Selection 338
9.7.3 Reactor Size 338
9.7.4 Heat-Recovery Heat-Exchanger Design 339
9.7.5 Carbon Combustion System 341
9.7.6 Design of Gas Liquid Separator System 343
9.7.7 Biomass Feed System 347
9.8 Corrosion 348
9.8.1 Mechanism of Corrosion 348
9.8.2 Prevention of Corrosion 349
9.9 Energy Conversion Efficiency 351
9.10 Major Challenges 351
Symbols and Nomenclature 352
10. Biomass Cofiring and Torrefaction 353

10.1 Introduction 353
10.2 Benefits and Shortcomings of Biomass Cofiring 354
10.3 Emission Reduction Through Biomass Cofiring 355
10.3.1 CO 2 Reduction 357
10.4 Carbon Capture and Storage (CCS) versus Biomass Firing 357
10.5 Cofiring Options 359
10.5.1 Direct Cofiring of Raw or Torrefied Biomass 359
10.5.2 Gasification Cofiring 361
10.5.3 Parallel Cofiring 361
10.6 Operating Problems of Biomass Cofiring 362
10.6.1 Combustion Issues 363
10.6.2 Fuel Preparation 363
10.6.3 Storage 364
10.6.4 Fouling, Agglomeration, and Corrosion 364
10.6.5 Biomass Variability 365
10.6.6 Capacity Reduction 366
10.6.7 Safety Issue 366