Preface xvii Contributors xxi 1 Fundamentals of Biological Processes for Wastewater Treatment 1 Jianlong Wang 1.1 Introduction, 1 1.2 Overview of Biological Wastewater Treatment, 2 1.2.1 The Objective of Biological Wastewater Treatment, 2 1.2.2 Roles of Microorganisms in Wastewater Treatment, 3 1.2.3 Types of Biological Wastewater Treatment Processes, 4 1.3 Classification of Microorganisms, 4 1.3.1 By the Sources of Carbon and Energy, 4 1.3.2 By Temperature Range, 6 1.3.3 Microorganism Types in Biological Wastewater Treatment, 7 1.4 Some Important Microorganisms in Wastewater Treatment, 8 1.4.1 Bacteria, 8 1.4.2 Fungi, 12 1.4.3 Algae, 15 1.4.4 Protozoans, 16 1.4.5 Rotifers and Crustaceans, 18 1.4.6 Viruses, 20 1.5 Measurement of Microbial Biomass, 21 1.5.1 Total Number of Microbial Cells, 21 1.5.2 Measurement of Viable Microbes on Solid Growth Media, 22 1.5.3 Measurement of Active Cells in Environmental Samples, 23 1.5.4 Determination of Cellular Biochemical Compounds, 24 1.5.5 Evaluation of Microbial Biodiversity by Molecular Techniques, 24 1.6 Microbial Nutrition, 24 1.6.1 Microbial Chemical Composition, 25 1.6.2 Macronutrients, 27 1.6.3 Micronutrients, 28 1.6.4 Growth Factor, 29 1.6.5 Microbial Empirical Formula, 31 1.7 Microbial Metabolism, 31 1.7.1 Catabolic Metabolic Pathways, 32 1.7.2 Anabolic Metabolic Pathway, 38 1.7.3 Biomass Synthesis Yields, 39 1.7.4 Coupling Energy-Synthesis Metabolism, 41 1.8 Functions of Biological Wastewater Treatment, 42 1.8.1 Aerobic Biological Oxidation, 42 1.8.2 Biological Nutrients Removal, 45 1.8.3 Anaerobic Biological Oxidation, 50 1.8.4 Biological Removal of Toxic Organic Compounds and Heavy Metals, 55 1.8.5 Removal of Pathogens and Parasites, 58 1.9 Activated Sludge Process, 59 1.9.1 Basic Process, 60 1.9.2 Microbiology of Activated Sludge, 61 1.9.3 Biochemistry of Activated Sludge, 66 1.9.4 Main Problems in the Activated Sludge Process, 67 1.10 Suspended- and Attached-Growth Processes, 69 1.10.1 Suspended-Growth Processes, 69 1.10.2 Attached-Growth Processes, 70 1.10.3 Hybrid Systems, 71 1.10.4 Comparison Between Suspended- and Attached-Growth Systems, 72 1.11 Sludge Production, Treatment and Disposal, 74 1.11.1 Sludge Production, 74 1.11.2 Sludge Treatment Processes, 76 1.11.3 Sludge Disposal and Application, 78 References, 79 2 Sludge Production: Quantification and Prediction for Urban Treatment Plants and Assessment of Strategies for Sludge Reduction 81 Mathieu Spe´randio, Etienne Paul, Yolaine Bessie`re, and Yu Liu 2.1 Introduction, 81 2.2 Sludge Fractionation and Origin, 82 2.2.1 Sludge Composition, 82 2.2.2 Wastewater Characteristics, 83 2.3 Quantification of Excess Sludge Production, 88 2.3.1 Primary Treatment, 88 2.3.2 Activated Sludge Process, 90 2.3.3 Phosphorus Removal (Biological and Physicochemical), 97 2.4 Practical Evaluation of Sludge Production, 99 2.4.1 Sludge Production Yield Variability with Domestic Wastewater, 99 2.4.2 Influence of Sludge Age: Experimental Data Versus Models, 100 2.4.3 ISS Entrapment in the Sludge, 103 2.4.4 Example of Sludge Production for a Different Case Study, 104 2.5 Strategies for Excess Sludge Reduction, 106 2.5.1 Classification of Strategies, 106 2.5.2 Increasing the Sludge Age, 107 2.5.3 Model-Based Evaluation of Advanced ESR Strategies, 109 2.6 Conclusions, 111 2.7 Nomenclature, 112 References, 114 3 Characterization of Municipal Wastewater and Sludge 117 Etienne Paul, Xavier Lefebvre, Mathieu Sperandio, Dominique Lefebvre, and Yu Liu 3.1 Introduction, 117 3.2 Definitions, 119 3.3 Wastewater and Sludge Composition and Fractionation, 120 3.3.1 Wastewater COD Fractions, 121 3.3.2 WAS COD Fractions, 122 3.3.3 ADS Organic Fractions, 122 3.4 Physical Fractionation, 123 3.4.1 Physical State of Wastewater Organic Matter, 123 3.4.2 Methods for Physical Fractionation of Wastewater Components, 123 3.5 Biodegradation Assays for Wastewater and Sludge Characterization, 124 3.5.1 Background, 124 3.5.2 Methods Based on Substrate Depletion, 125 3.5.3 Methods Based on Respirometry, 125 3.5.4 Anaerobic Biodegradation Assays, 128 3.6 Application to Wastewater COD Fractionation, 131 3.6.1 Global Picture of Fractionation Methods and Wastewater COD Fractions, 131 3.6.2 Application of Physical Separation for Characterization of Wastewater COD Fractions, 132 3.6.3 Biodegradable COD Fraction, 133 3.6.4 Relation Between Physical and Biological Properties of Organic Fractions, 136 3.6.5 Unbiodegradable Particulate COD Fractions, 137 3.7 Assessment of the Characteristics of Sludge and Disintegrated Sludge, 143 3.7.1 Physical Fractionation of COD Released from Sludge Disintegration Treatment, 143 3.7.2 Biological Fractionation of COD Released from Sludge Disintegration Treatment, 145 3.7.3 Biodegradability of WAS in Anaerobic Digestion, 145 3.7.4 Unbiodegradable COD in Anaerobic Digestion, 146 3.8 Nomenclature, 147 References, 149 4 Oxic-Settling-Anaerobic Process for Enhanced Microbial Decay 155 Qingliang Zhao and Jianfang Wang 4.1 Introduction, 155 4.2 Description of the Oxic-Settling-Anaerobic Process, 156 4.2.1 Oxic-Settling-Anaerobic Process, 156 4.2.2 Characteristics of the OSA Process, 157 4.3 Effects of an Anaerobic Sludge Tank on the Performance of an OSA System, 158 4.3.1 Fate of Sludge Anaerobic Exposure in an OSA System, 158 4.3.2 Effect of Sludge Anaerobic Exposure on Biomass Activity, 160 4.4 Sludge Production in an OSA System, 161 4.5 Performance of an OSA System, 162 4.5.1 Organic and Nutrient Removal, 162 4.5.2 Sludge Settleability, 163 4.6 Important Influence Factors, 164 4.6.1 Influence of the ORP on Sludge Production, 164 4.6.2 Influence of the ORP on Performance of an OSA System, 164 4.6.3 Influence of SAET on Sludge Production, 166 4.6.4 Influence of SAET on the Performance of an OSA System, 166 4.7 Possible Sludge Reduction in the OSA Process, 166 4.7.1 Slow Growers, 167 4.7.2 Energy Uncoupling Metabolism, 167 4.7.3 Sludge Endogenous Decay, 169 4.8 Microbial Community in an OSA System, 171 4.8.1 Staining Analysis, 172 4.8.2 FISH Analysis, 173 4.9 Cost and Energy Evaluation, 174 4.10 Evaluation of the OSA Process, 175 4.11 Process Development, 176 4.11.1 Sludge Decay Combined with Other Sludge Reduction Mechanisms, 176 4.11.2 Improved Efficiency in Sludge Anaerobic Digestion, 177 4.11.3 Combined Minimization of Excess Sludge with Nutrient Removal, 178 References, 179 5 Energy Uncoupling for Sludge Minimization: Pros and Cons 183 Bo Jiang, Yu Liu, and Etienne Paul 5.1 Introduction, 183 5.2 Overview of Adenosine Triphosphate Synthesis, 184 5.2.1 Electron Transport System, 184 5.2.2 Mechanisms of Oxidative Phosphorylation, 185 5.3 Control of ATP Synthesis, 187 5.3.1 Diversion of PMF from ATP Synthesis to Other Physiological Activities, 187 5.3.2 Inhibition of Oxidative Phosphorylation, 187 5.3.3 Uncoupling of Electron Transport and Oxidative Phosphorylation, 188 5.4 Energy Uncoupling for Sludge Reduction, 189 5.4.1 Chemical Uncouplers Used for Sludge Reduction, 189 5.4.2 Uncoupling Activity, 198 5.5 Modeling of Uncoupling Effect on Sludge Production, 200 5.6 Sideeffects of Chemical Uncouplers, 202 5.7 Full-Scale Application, 204 References, 204 6 Reduction of Excess Sludge Production Using Ozonation or Chlorination: Performance and Mechanisms of Action 209 Etienne Paul, Qi-Shan Liu, and Yu Liu 6.1 Introduction, 209 6.2 Significant Operational Results for ESP Reduction with Ozone, 210 6.2.1 Options for Combining Ozonation and Biological Treatment, 210 6.2.2 ESP Reduction Performance, 212 6.2.3 Assessing Ozone Efficiency for Mineral ESP Reduction, 215 6.3 Side Effects of Sludge Ozonation, 216 6.3.1 Outlet SS and COD, 216 6.3.2 N Removal, 218 6.4 Cost Assessment, 221 6.5 Effect of Ozone on Sludge, 222 6.5.1 Synergy Between Ozonation and Biological Treatment, 222 6.5.2 Some Fundamentals of Ozone Transfer, 222 6.5.3 Sludge Composition, 224 6.5.4 Effect of Ozone on Activated Sludge: Batch Tests, 226 6.5.5 Effect of Ozone on Biomass Activity, 228 6.5.6 Competition for Ozone in Mixed Liquor, 231 6.6 Modeling Ozonation Effect, 233 6.7 Remarks on Sludge Ozonation, 236 6.8 Chlorination in Water and Wastewater Treatment, 236 6.8.1 Introduction, 236 6.8.2 Chlorination-Assisted Biological Process for Sludge Reduction, 237 6.8.3 Effect of Chlorine Dosage on Sludge Reduction, 239 6.8.4 Chlorine Requirement, 240 6.9 Nomenclature, 242 References, 244 7 High-Dissolved-Oxygen Biological Process for Sludge Reduction 249 Zhi-Wu Wang 7.1 Introduction, 249 7.2 Mechanism of High-Dissolved-Oxygen Reduced Sludge Production, 251 7.2.1 High-Dissolved-Oxygen Decreased Specific Loading Rate, 251 7.2.2 High-Dissolved-Oxygen Uncoupled Microbial Metabolism Pathway, 252 7.2.3 High-Dissolved-Oxygen Shifted Microbial Population, 254 7.3 Limits of High-Dissolved-Oxygen Process for Reduced Sludge Production, 255 References, 256 8 Minimizing Excess Sludge Production Through Membrane Bioreactors and Integrated Processes 261 Philip Chuen-Yung Wong 8.1 Introduction, 261 8.2 Mass Balances, 262 8.3 Integrated Processes Based on Lysis-Cryptic Growth, 266 8.3.1 Mass Balance Incorporating Sludge Disintegration and Solubilization, 268 8.3.2 Thermal and Thermal-Alkaline Treatment, 274 8.3.3 Ozonation, 276 8.3.4 Sonication, 279 8.4 Predation, 283 8.5 Summary and Concluding Remarks, 285 References, 286 9 Microbial Fuel Cell Technology for Sustainable Treatment of Organic Wastes and Electrical Energy Recovery 291 Shi-Jie You, Nan-Qi Ren, and Qing-Liang Zhao 9.1 Introduction, 291 9.2 Fundamentals, Evaluation, and Design of MFCs, 293 9.2.1 Principles, 293 9.2.2 Performance Evaluation, 293 9.2.3 MFC Configurations, 294 9.3 Performance of Anodes, 295 9.3.1 Electrode Materials, 295 9.3.2 Microbial Electron Transfer, 296 9.3.3 Electron Donors, 298 9.4 Cathode Performances, 299 9.4.1 Electron Acceptors, 300 9.4.2 Electrochemical Fundamentals of the Oxygen Reduction Reaction, 302 9.4.3 Air-Cathode Structure and Function, 303 9.4.4 Electrocatalyst, 304 9.5 Separator, 306 9.6 pH Gradient and Buffer, 307 9.7 Applications of MFC-Based Technology, 309 9.7.1 Biosensors, 309 9.7.2 Hydrogen Production, 310 9.7.3 Desalination, 310 9.7.4 Hydrogen Peroxide Synthesis, 312 9.7.5 Environmental Remediation, 312 9.8 Conclusions and Remarks, 314 References, 315 10 Anaerobic Digestion of Sewage Sludge 319 Kuan-Yeow Show, Duu-Jong Lee, and Joo-Hwa Tay 10.1 Introduction, 319 10.2 Principles of Anaerobic Digestion, 320 10.2.1 Hydrolysis and Acidogenesis, 321 10.2.2 Methane Formation, 323 10.3 Environmental Requirements and Control, 324 10.3.1 pH, 324 10.3.2 Alkalinity, 325 10.3.3 Temperature, 326 10.3.4 Nutrients, 326 10.3.5 Toxicity, 327 10.4 Design Considerations for Anaerobic Sludge Digestion, 329 10.4.1 Hydraulic Detention Time, 329 10.4.2 Solids Loading, 330 10.4.3 Temperature, 331 10.4.4 Mixing, 331 10.5 Component Design of Anaerobic Digester Systems, 331 10.5.1 Tank Configurations, 331 10.5.2 Temperature Control, 333 10.5.3 Sludge Heating, 333 10.5.4 Auxiliary Mixing, 334 10.6 Reactor Configurations, 336 10.6.1 Conventional Anaerobic Digesters, 336 10.6.2 Anaerobic Contact Processes, 338 10.6.3 Other Types of Configurations, 340 10.7 Advantages and Limitations of Anaerobic Sludge Digestion, 343 10.8 Summary and New Horizons, 344 References, 345 11 Mechanical Pretreatment-Assisted Biological Processes 349 He´le`ne Carre`re, Damien J. Batstone, and Etienne Paul 11.1 Introduction, 349 11.2 Mechanisms of Mechanical Pretreatment, 350 11.2.1 From Sludge Disintegration to Cell Lysis and Chemical Transformation, 350 11.2.2 Specific Energy, 350 11.2.3 Sonication, 351 11.2.4 Grinding, 353 11.2.5 Shear-Based Methods: High-Pressure and Collision Plate Homogenization, 353 11.2.6 Lysis Centrifuge, 353 11.3 Impacts of Treatment: Rate vs. Extent of Degradability, 353 11.3.1 Grinding, 354 11.3.2 Ultrasonication, 354 11.4 Equipment for Mechanical Pretreatment, 354 11.4.1 Sonication, 355 11.4.2 Grinding, 357 11.4.3 Shear-Based Methods: High-Pressure and Collision Plate Homogenization, 358 11.4.4 Lysis Centrifuge, 359 11.5 Side Effects, 359 11.6 Mechanical Treatment Combined with Activated Sludge, 360 11.7 Mechanical Treatment Combined with Anaerobic Digestion, 361 11.7.1 Performances, 361 11.7.2 Dewaterability, 363 11.7.3 Full-Scale Performance and Market Penetration, 364 11.7.4 Energy Balance, 365 11.7.5 Nutrient Release and Recovery/Removal, 366 11.8 Conclusion, 367 References, 368 12 Thermal Methods to Enhance Biological Treatment Processes 373 Etienne Paul, He´le`ne Carre`re, and Damien J. Batstone 12.1 Introduction, 373 12.2 Mechanisms, 374 12.2.1 Effects of Heating on Cells, 374 12.2.2 Effect of Heating on Sludge, 376 12.2.3 Mechanisms of Thermal Pretreatment, 388 12.3 Devices for Thermal Treatment, 388 12.3.1 Low-Temperature Pretreatment, 389 12.3.2 High-Temperature Pretreatment, 390 12.4 Applications of Thermal Treatment, 390 12.4.1 Thermal Treatment Combined with Activated Sludge, 390 12.4.2 Thermal Pretreatment to Anaerobic Digestion, 394 12.5 Conclusions, 398 References, 399 13 Combustion, Pyrolysis, and Gasification of Sewage Sludge for Energy Recovery 405 Yong-Qiang Liu, Joo-Hwa Tay, and Yu Liu 13.1 Introduction, 405 13.2 Characteristics and Dewatering of Sewage Sludge, 406 13.3 Energy Recovery from Sludge, 408 13.3.1 Incineration, 408 13.3.2 Pyrolysis and Gasification, 416 13.3.3 Wet Oxidation, 419 13.3.4 Thermal Plasma Pyrolysis and Gasification, 420 References, 421 14 Aerobic Granular Sludge Technology for Wastewater Treatment 429 Bing-Jie Ni and Han-Qing Yu 14.1 Introduction, 429 14.2 Technological Starting Points: Cultivating Aerobic Granules, 431 14.2.1 Substrate Composition, 431 14.2.2 Organic Loading Rate, 433 14.2.3 Seed Sludge, 433 14.2.4 Reactor Configuration, 433 14.2.5 Operational Parameters, 434 14.3 Mechanisms of the Aerobic Granulation Process, 436 14.3.1 Granulation Steps, 436 14.3.2 Selective Pressure, 437 14.4 Characterization of Aerobic Granular Sludge, 438 14.4.1 Biomass Yield and Sludge Reduction, 438 14.4.2 Formation and Consumption of Microbial Products, 440 14.4.3 Microbial Structure and Diversity, 441 14.4.4 Physicochemical Characteristics, 442 14.5 Modeling Granule-Based SBR for Wastewater Treatment, 447 14.5.1 Nutrient Removal in Granule-Based SBRs, 447 14.5.2 Multiscale Modeling of Granule-Based SBR, 450 14.6 Bioremediation of Wastewaters with Aerobic Granular Sludge Technology, 452 14.6.1 Organic Wastewater Treatment, 452 14.6.2 Biological Nutrient Removal, 452 14.6.3 Domestic Wastewater Treatment, 454 14.6.4 Xenobiotic Contaminant Bioremediation, 454 14.6.5 Removal of Heavy Metals or Dyes, 455 14.7 Remarks, 456 References, 457 15 Biodegradable Bioplastics from Fermented Sludge, Wastes, and Effluents 465 Etienne Paul, Elisabeth Neuhauser, and Yu Liu 15.1 Introduction, 465 15.1.1 Context of Poly(hydroxyalkanoate) Production from Sludge and Effluents, 465 15.1.2 Industrial Context for PHA Production, 467 15.2 PHA Structure, 469 15.3 Microbiology for PHA Production, 469 15.4 Metabolism of PHA Production, 471 15.4.1 PHB Metabolism, 472 15.4.2 Metabolism for Other PHA Production, 475 15.4.3 Nutrient Limitations, 476 15.4.4 PHA Metabolism in Mixed Cultures, 477 15.4.5 Effect of Substrate in Mixed Cultures, 478 15.5 PHA Kinetics, 479 15.6 PHA Storage to Minimize Excess Sludge Production in Wastewater Treatment Plants, 481 15.7 Choice of Process and Reactor Design for PHA Production, 482 15.7.1 Criteria, 482 15.7.2 Anaerobic–Aerobic Process, 483 15.7.3 Aerobic Dynamic Feeding Process, 485 15.7.4 Fed-Batch Process Under Nutrient Growth Limitation, 486 15.8 Culture Selection and Enrichment Strategies, 487 15.9 PHA Quality and Recovery, 489 15.10 Industrial Developments, 490 References, 492 Index 499

A comprehensive guide to sludge management, reuse, and disposal When wastewater is treated, reducing organic material to carbon dioxide, water, and bacterial cells—the cells are disposed of, producing a semisolid and nutrient-rich byproduct called sludge. The expansion in global population and industrial activity has turned the production of excess sludge into an international environmental challenge, with the ultimate disposal of excess sludge now one of the most expensive problems faced by wastewater facilities. Written by two leading environmental engineers, Biological Sludge Minimization and Biomaterials/Bioenergy Recovery Technologies offers a comprehensive look at cutting-edge techniques for reducing sludge production, converting sludge into a value-added material, recovering useful resources from sludge, and sludge incineration. Reflecting the impact of new stringent environmental legislation, this book offers a frank appraisal of how sludge can be realistically managed, covering key concerns and the latest tools: Fundamentals of biological processes for wastewater treatment, wastewater microbiology, and microbial metabolism, essential to understanding how sludge is producedPrediction of primary sludge and waste-activated sludge production, among the chief design and operational challenges of a wastewater treatment plantTechnologies for sludge reduction, with a focus on reducing microbial growth yield as well as enhancing sludge disintegrationThe use of anerobic digestion of sewage sludge for biogas recovery, in terms of process fundamentals, design, and operationThe use of the microbial fuel cell (MFC) system for the sustainable treatment of organic wastes and electrical energy recovery