Biomass Conversion Processes for Energy and Fuels

I. Biomass Sources.- 1. Residues and Wastes.- 1. Introduction.- 2. Municipal Solid Wastes.- 2.1. Quantity.- 2.2. Characteristics.- 2.3. Fuel Value.- 2.4. Upgrading the Fuel Value.- 3. Municipal Sewage Sludges.- 3.1. Types.- 3.2. Quantities.- 3.3. Characteristics.- 3.4. Utilization of Sludges.- 4. Animal Wastes.- 4.1. Quantity and Quality.- 4.2. Utilization.- 5. Crop Residues.- 5.1. Types.- 5.2. Quantity.- 5.3. Quality.- 5.4. Seasonality of Generation.- 5.5. Location of Residues.- 5.6. Other Factors.- 6. Industrial Wastes.- 7. Forest Products.- 7.1. Logging Residues.- 7.2. Residues from Wood Product Manufacturing.- 7.3. Residues from Pulp and Paper Manufacture.- References.- 2. Agricultural and Forestry Residues.- 1. Introduction.- 2. Methods of Data Analysis.- 2.1. Species Selected for Study and Analytical Rationale.- 2.2. Sources of Information.- 3. Chemical Quality of Agricultural and Forestry Residues.- 4. Estimates of Agricultural and Forestry Residues.- 4.1. Regional Distribution.- 4.2. Seasonal Availability.- References.- 3. Aquatic Biomass.- 1. Introduction.- 2. Algal Biomass.- 2.1. Yield.- 2.2. Feasibility of Culture Systems.- 3. Aquatic Macrophyte Biomass.- 3.1. Yield of Selected Species.- 3.2. Yield of Marsh Communities.- 3.3. Energy Equivalents and Nutrient Contents.- 4. Discussion.- References.- 4. Marine Biomass.- 1. Introduction.- 2. Biological Characteristics of Marine Plants.- 3. Geographical Distribution of Marine Plants.- 4. Primary Production.- 4.1. Fundamental Considerations.- 4.2. Geographical Distribution of Primary Production.- 4.3. Some Highly Productive Plants.- 5. Chemical Properties of Marine Plants.- 5.1. Inorganic Chemistry.- 5.2. Organic Chemistry.- 5.3. Energy Content.- 6. Commercial Culture and Cultivation.- 7. Utilization of Marine Plants.- 8. Relationship of Primary Production and Chemical Composition to Marine Energy Crops.- 8.1. Preprocessing.- 8.2. Processing Byproducts.- 8.3. Potential Energy Yield.- References.- 5. Silvicultural Energy Farms.- 1. Introduction.- 2. The Silvicultural Energy Farm Concept.- 3. Conceptual Design and Operation of the Silvicultural Energy Farm.- 3.1. Energy Farm Design Parameters and Layout.- 3.2. Energy Farm Operational and Cost Data.- 3.2.1. Energy Farm Installation.- 3.2.1a. Land Acquisition.- 3.2.1b. Land Preparation.- 3.2.1c. Work Roads.- 3.2.1d. Irrigation Systems.- 3.2.1e. Planting.- 3.2.2. Energy Farm Operation.- 3.2.2a. Irrigation.- 3.2.2b. Fertilization.- 3.2.2c. Weed Control.- 3.2.2d. Harvesting.- 3.2.2e. Transportation.- 3.2.2f. Maintenance.- 3.2.2g. Support Costs.- 4. Biomass Production Economics.- 4.1. Biomass Production Costs.- 4.2. Production Costs Components.- 5. Energy Balance for Biomass Production.- 6. The Potential of Silvicultural Energy Farming.- 7. Conclusions.- References.- II. Conversion Processes.- Section A. Direct Combustion Processes.- 6. Basic Principles of Direct Combustion.- 1. Introduction.- 2. Composition.- 2.1. Moisture Content.- 2.2. Ash Content.- 2.3. Organic Content.- 3. Pyrolysis and Heat of Combustion of Biomass and Its Components.- 4. Combustion Process.- References.- 7. The Andco-Torrax System.- 1. Introduction.- 2. Description of Process.- 2.1. Gasifier.- 2.2. Fuel Gas System.- 2.3. Integrated Complete Combustion System.- 2.3.1. Gasifier.- 2.3.2. Secondary Combustion Chamber.- 2.3.3. Regenerative Towers.- 2.3.4. Waste Heat Boiler.- 2.3.5. Gas Cleaning System.- 3. Review of Plant Operations.- 3.1. Demonstration Plant.- 3.2. Commercial Plants.- 4. Heat and Mass Balances.- 5. Some Applications of the Process.- 5.1. Tires, Waste Rubber, and MSW.- 5.2. Sewage Sludge and MSW.- References.- Section B. Thermochemical Processes.- 8. Basic Principles of Thermochemical Conversion.- 1. Introduction.- 2. Kinetics and Thermodynamics Framework.- 2.1. Heating Values.- 2.2. Standard States.- 2.3. Enthalpy Tables.- 3. Gasification of Biomass.- 3.1. Types of Gasification Technologies.- 3.2. Governing Equations.- 3.3. Downstream Processing.- 3.3.1. Gas Purification.- 3.3.2. Shift Conversion.- 3.3.3. Additional Processing.- 3.3.3a. Substitute Natural Gas (SNG).- 3.3.3b. Methanol.- 3.3.3c. Ammonia.- 4. Liquefaction of Biomass.- 4.1. Types of Liquefaction Technologies.- 4.2. Governing Equations.- 4.3. Parallel or Downstream Processing.- 4.3.1. Gasification and Recycle.- 4.3.2. Solids Removal.- 4.3.3. Liquid Recovery/Drying.- References.- 9. The Occidental Flash Pyrolysis Process.- 1. Introduction.- 2. Process Description.- 2.1. Front End System.- 2.2. Pyrolysis System.- 3. Material and Energy Balances.- 4. Product Characterization.- 4.1. Pyrolytic Oil.- 4.2. Glass.- 4.3. Ferrous Metal.- 4.4. Aluminum.- 5. Further Applications.- 5.1. Solid Refuse Derived Fuel.- 5.2. Flash Pyrolysis of Industrial Wastes.- 5.3. Gasification.- References.- 10. Carboxylolysis of Biomass.- 1. Basic Process Description.- 1.1. Feedstock Applicability.- 1.2. Potential Products.- 2. Background.- 2.1. Albany PDU Design and Construction.- 2.2. PDU Operational Results.- 2.3. Supporting Research.- 3. Conceptual Process Description.- 3.1. Reactor.- 3.2. Product Separation.- 3.3. Gasification.- 3.4. Design Basis.- 3.5. Conceptual Plant and Equipment Description.- 3.5.1. Wood Preparation.- 3.5.2. Syngas Production.- 3.5.3. Reaction Process.- 3.5.4. Product Separation.- 3.5.5. Plant Balance.- 4. Process Efficiency.- 5. Conceptual Economics.- References.- 11. The Tech-Air Pyrolysis Process.- 1. Introduction.- 2. Bench-Scale Reactor.- 3. Prototype Plant.- 4. Pilot Plant.- 5. Demonstration Plant.- 6. Process Description.- 7. Product Yields.- 8. Product Characteristics.- 9. Product Uses.- 10. Process Efficiency.- References.- 12. The Purox Process.- 1. Introduction.- 2. Description of Process.- 2.1. Preprocessing Plant.- 2.2. The Basic Process.- 2.3. Purox Gasification Scheme.- 2.4. Gas Cleaning.- 2.5. Wastewater Treatment.- 2.6. Oxygen Plant.- 2.7. Gas Compression and Drying.- 2.8. Process Equipment.- 3. Performance.- 4. Case History.- 5. Economics.- 5.1. Construction and Operating Costs.- 5.2. Product Cost Analysis.- 6. Applications of Purox Fuel Gas.- References.- Suggested Reading.- 13. Gasification.- 1. Introduction.- 2. Types of Gasifiers.- 2.1. Fixed Bed.- 2.2. Fluidized Bed.- 2.3. Entrained Bed.- 3. Fuels for Gasifiers.- 4. Thermochemistry.- 5. Design Considerations.- 6. Performance Characteristics.- 7. Combustion Characteristics.- 8. Ancillary Equipment.- 9. Utilization of Biomass Fuel.- References.- Suggested Reading.- 14. The Syngas Recycle Process.- 1. The Concept.- 2. Experimental Basis for the Process.- 3. Reactor Design Considerations.- 4. Material Balance.- 5. Integrated Process Flowsheet.- 6. Process Energy and Material Balances.- References.- Section C. Biochemical Conversion Processes.- 15. Basic Principles of Bioconversions in Anaerobic Digestion and Methanogenesis.- 1. Introduction.- 2. Stages of the Fermentation.- 2.1. Two-Stage Scheme.- 2.2. Three-Stage Scheme.- 2.3. Metabolic Groups Involved in Partial Methane Fermentation.- 3. The Methanogens.- 3.1. Physiology.- 3.2. Phylogeny and Taxonomy.- 3.3. Substrates.- 4. The Fermentative Bacteria.- 4.1. Fermentation of Polysaccharides.- 4.2. First Site of H2 Regulation.- 4.3. Fermentation of Other Complex Substrates.- 5. The H2-Producing Acetogenic Bacteria.- 5.1. Ethanol and Lactate Fermentations.- 5.2. Fatty Acid-Oxidizing, H2-Producing Bacteria.- 5.3. Second Site of H2 Regulation.- 6. Stoichiometry, Kinetics, Environmental and Nutrient Parameters of Fermentation.- 6.1. Stoichiometry.- 6.2. Kinetic Factors Influencing Efficiency.- 6.2.1. Effect of Retention Time (RT).- 6.2.2. Rate-Limiting Step.- 6.2.3. Effect of Volumetric Organic Loading Rate.- 6.3. Nutrient and Environmental Requirements.- 7. Summary.- References.- 16. Design of Small-Scale Biogas Plants.- 1. Introduction.- 2. Biomass Conversion to Methane.- 2.1. The Biogasification Process.- 2.2. Large-Scale Commercial Endeavors.- 2.3. Potential for Small-Scale Facilities.- 3. Small-Scale Biogas-Processing Facilities.- 3.1. Biogas Plants for Dairies and Farms.- 3.2. Pollution-Control Advantages.- 3.3. Development of Small-Scale Biogas Plants.- 4. Biogas Plant Design and Construction.- 4.1. Process Flow Description.- 4.2. Methane Storage System.- 4.3. Fertilizer Production.- 5. Economic Feasibility and Marketability.- References.- 17. Anaerobic Digestion of Kelp.- 1. Introduction.- 2. Characteristics of Kelp Feeds.- 3. Biomethanogenesis of Kelp.- 3.1. Performance Parameters.- 3.1.1. Gas Production.- 3.1.2. Conversion of Organic Matter.- 3.2. Maximum Theoretical Yields and Heat of Reaction.- 3.3. Bench-Scale Digestion Studies.- 3.3.1. Organic Composition of Feeds.- 3.3.2. Potential Nutrient Limitation.- 3.3.3. Inoculum.- 3.3.4. Temperature.- 3.3.5. Inhibitory Substances in Feed.- 3.3.6. Hydraulic Retention Time (HRT).- 3.3.7. Feed Concentration.- 3.3.8. Particle Size.- 3.3.9. Mixing.- 3.3.10. Feeding Frequency.- 3.3.11. Catabolite Repression.- 3.4. Component and Energy Balance for Biomethanation of Raw Kelp.- 4. Summary.- References.- 18. Basic Principles of Ethanol Fermentation.- 1. Introduction.- 2. Why Microbes Produce Ethanol?.- 3. Substrates for Ethanol Production.- 4. Substrate Preparation.- 5. Substrate Metabolism.- 6. Effect of Microorganisms on Ethanol Production.- 7. Effect of Fermentation Parameters.- 8. Fermentation Systems.- 9. Conclusions.- References.- 19. Ethanol Production by Fermentation.- 1. Introduction.- 2. Feedstock Selection.- 2.1. Pretreatment Design.- 2.2. Pretreatment Costs.- 2.3. Feedstock Price.- 2.4. By-Product Credit.- 2.5. Waste Treatment.- 3. Process Description.- 3.1. Feedstock Preparation.- 3.1.1. Physical Reduction.- 3.1.2. Substrate Hydrolysis.- 3.1.3. Feedstock Sterilization.- 3.1.4. Concentration Adjustment.- 3.2. Ethanol Fermentation.- 3.2.1. Batch Fermentation.- 3.2.2. Continuous Fermentation.- 3.2.3. Yeast Supply.- 3.3. Ethanol Recovery.- 3.3.1. Stillage Separation.- 3.3.2. Anhydrous Distillation.- 3.3.3. Product Specifications.- 3.4. By-Product Recovery.- 4. Conversion Efficiency.- 4.1. Independent Plant.- 4.2. Integrated Plant.- 5. Energy Efficiency.- 6. Conclusion.- References.- III.Technical and Economic Considerations.- 20. Technical Considerations of Biomass Conversion Processes.- 1. Material Balances.- 1.1. Basic Equations and Guidelines.- 1.1.1. System Boundaries; Choosing a Basis; Composition Data.- 1.1.2. Chemical Reactions and Yields.- 1.1.3. Units.- 1.2. Applications to Conversion Processes.- 1.2.1. Air-Blown Gasifier.- 1.2.2. Pyrolysis-Gasification Reactor.- 1.2.3. Pyrolysis of Wood.- 2. Energy Balances.- 2.1. Basic Equations and Guidelines.- 2.1.1. Calculation of Enthalpy Changes.- 2.1.2. Simplified Forms of the Energy Balance Equation.- 2.2. Applications to Conversion Processes.- 2.2.1. Pyrolysis of Wood.- 2.2.2. Pyrolysis-Gasification Reactor.- 3. Evaluation of Process Efficiency.- 3.1. Criteria.- 3.2. Thermal or Energy Efficiency.- 3.3. Thermodynamic Efficiency.- 3.4. Recommendations.- References.- 21. Economic Considerations of Biomass Conversion Processes.- 1. Introduction.- 1.1. Level of Estimating the Desired Precision.- 1.2. Assumed Study Purpose and Conditions.- 2. General Guidelines.- 2.1. Analysis Uniformity.- 2.2. Life Cycle Costing.- 2.3. Money Time Value.- 3. Capital Investment Economics.- 3.1. Plant General Facilities.- 3.2. Plant Utilities.- 3.3. Land Investment.- 3.4. Working Capital.- 3.5. Organization and Start-Up Costs.- 3.6. Depreciable Investment.- 3.7. Plant On-Stream Factor.- 3.8. Conversion Plant Capacities.- 4. Feedstock Prices.- 5. Operating and Maintenance Costs.- 6. Calculation of Revenue Requirements.- 6.1. Revenue Required—Non Regulated Industry.- 6.2. Revenue Required—Regulated Industry.- References.