Biological treatment processes (humana, 2008)

Biological Treatment Processes
Humana Press
Handbook of Environmental Engineering Series
Volume 1: Air Pollution Control Engineering. L. K. Wang, N. C. Pereira, and Y. T. Hung (eds.) 504 pp.
(2004)
Volume 2: Advanced Air and Noise Pollution Control. L. K. Wang, N. C. Pereira, and Y. T. Hung (eds.)
526 pp. (2005)
Volume 3: Physicochemical Treatment Processes. L. K. Wang, Y. T. Hung, and N. K. Shammas (eds.)
723 pp. (2005)
Volume 4: Advanced Physicochemical Treatment Processes. L. K. Wang, Y. T. Hung, and N. K.
Shammas (eds.) 690 pp. (2006)
Volume 5: Advanced Physicochemical Treatment Technologies. L. K. Wang, Y. T. Hung, and N. K.
Shammas (eds.) 710 pp. (2007)
Volume 6: Biosolids Treatment Processes. L. K. Wang, N. K. Shammas, and Y. T. Hung (eds.) 820 pp.
(2007)
Volume 7: Biosolids Engineering and Management. L. K. Wang, N. K. Shammas, and Y. T. Hung (eds.)
800 pp. (2008)
Volume 8: Biological Treatment Processes. L. K. Wang, N. C. Pereira, Y. T. Hung, and N. K. Shammas
(eds.) 818 pp. (2009)
Volume 9: Advanced Biological Treatment Processes. L. K. Wang, N. K. Shammas, and Y. T. Hung
(eds.) (2009)
Volume 10: Environmental Biotechnology. L. K. Wang, J. H. Tay, V. Ivanov, and Y. T. Hung (eds.)
(2009)
Volume 11: Environmental Bioengineering. L. K. Wang, J. H. Tay, S. T. Tay, and Y. T. Hung (eds.)
(2009)
VOLUME 8
HANDBOOK OF ENVIRONMENTAL ENGINEERING
Biological Treatment
Processes
Edited by

Lawrence K. Wang, PhD, PE, DEE
Lenox Institute of Water Technology, Lenox, MA
Krofta Engineering Corporation, Lenox, MA
Zorex Corporation, Newtonville, NY
Norman C. Pereira, PhD
Monsanto Company
St. Louis, MO (Retired)
Yung-Tse Hung, PhD, PE, DEE
Department of Civil and Environmental Engineering
Cleveland State University, Cleveland, OH
Consulting Editor
Nazih K. Shammas, PhD
Lenox Institute of Water Technology, Lenox, MA
Krofta Engineering Corporation, Lenox, MA
Editors
Lawrence K. Wang Yung-Tse Hung
Dean & Director (retired), Professor, Department of Civil
Lenox Institute of Water Technology and Environmental Engineering
Assistant to the President (retired), Cleveland State University
Krofta Engineering Corporation 16945 Deerfield Drive, Strongsville, OH 44136, USA
Vice President (retired),
Zorex Corporation
1 Dawn Drive, Latham, NY 12110 USA


Norman C. Pereira
14620 Mill Spring Ct.
Chesterfield, MO 63017

Consulting Editor

Nazih K. Shammas
Professor and Environmental Engineering Consultant
Ex-Dean and Director, Lenox Institute of Water Technology
Advisor, Krofta Engineering Corporation
35 Flintstone Drive
Pittsfield, MA 01201 USA


ISBN 978-1-58829-163-9 e-ISBN 978-1-60327-156-1
DOI: 10.1007/978-1-60327-156-1
Library of Congress Control Number: 2008922724
c
 2009 Humana Press, a part of Springer Science+Business Media, LLC
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Preface
The past thirty years have seen the emergence of a growing desire worldwide that
positive actions be taken to restore and protect the environment from the degrading
effects of all forms of pollution – air, water, soil, and noise. Since pollution is a direct or

indirect consequence of waste, the seemingly idealistic demand for “zero discharge”
can be construed as an unrealistic demand for zero waste. However, as long as
waste continues to exist, we can only attempt to abate the subsequent pollution by
converting it to a less noxious form. Three major questions usually arise when a
particular type of pollution has been identified: (1) How serious is the pollution?
(2) Is the technology to abate it available? and (3) Do the costs of abatement justify
the degree of abatement achieved? This book is one of the volumes of the Handbook
of Environmental Engineering series. The principal intention of this series is to help
readers formulate answers to the last two questions above.
The traditional approach of applying tried-and-true solutions to specific pollution
problems has been a major contributing factor to the success of environmental engi-
neering, and has accounted in large measure for the establishment of a “methodology
of pollution control.” However, the realization of the ever-increasing complexity and
interrelated nature of current environmental problems renders it imperative that
intelligent planning of pollution abatement systems be undertaken. Prerequisite to
such planning is an understanding of the performance, potential, and limitations of
the various methods of pollution abatement available for environmental scientists
and engineers. In this series of handbooks, we will review at a tutorial level a broad
spectrum of engineering systems (processes, operations, and methods) currently
being utilized, or of potential utility, for pollution abatement. We believe that the
unified interdisciplinary approach presented in these handbooks is a logical step in
the evolution of environmental engineering.
Treatment of the various engineering systems presented will show how an engi-
neering formulation of the subject flows naturally from the fundamental principles
and theories of chemistry, microbiology, physics, and mathematics. This emphasis on
fundamental science recognizes that engineering practice has in recent years become
more firmly based on scientific principles rather than on its earlier dependency on
empirical accumulation of facts. It is not intended, though, to neglect empiricism
where such data lead quickly to the most economic design; certain engineering
systems are not readily amenable to fundamental scientific analysis, and in these

instances we have resorted to less science in favor of more art and empiricism.
Since an environmental engineer must understand science within the context of
application, we first present the development of the scientific basis of a particular
subject, followed by exposition of the pertinent design concepts and operations,
v
vi Preface
and detailed explanations of their applications to environmental quality control or
remediation. Throughout the series, methods of practical design and calculation are
illustrated by numerical examples. These examples clearly demonstrate how orga-
nized, analytical reasoning leads to the most direct and clear solutions. Wherever
possible, pertinent cost data have been provided.
Our treatment of pollution-abatement engineering is offered in the belief that the
trained engineer should more firmly understand fundamental principles, be more
aware of the similarities and/or differences among many of the engineering systems,
and exhibit greater flexibility and originality in the definition and innovative solution
of environmental pollution problems. In short, the environmental engineer should by
conviction and practice be more readily adaptable to change and progress.
Coverage of the unusually broad field of environmental engineering has
demanded an expertise that could only be provided through multiple authorships.
Each author (or group of authors) was permitted to employ, within reasonable limits,
the customary personal style in organizing and presenting a particular subject area;
consequently, it has been difficult to treat all subject material in a homogeneous
manner. Moreover, owing to limitations of space, some of the authors’ favored topics
could not be treated in great detail, and many less important topics had to be merely
mentioned or commented on briefly. All authors have provided an excellent list of
references at the end of each chapter for the benefit of interested readers. As each
chapter is meant to be self-contained, some mild repetition among the various texts
was unavoidable. In each case, all omissions or repetitions are the responsibility of the
editors and not the individual authors. With the current trend toward metrication, the
question of using a consistent system of units has been a problem. Wherever possible,

the authors have used the British system (fps) along with the metric equivalent (mks,
cgs, or SIU) or vice versa. The editors sincerely hope that this duplicity of units’ usage
will prove to be useful rather than being disruptive to the readers.
The goals of the Handbook of Environmental Engineering series are: (1) to cover entire
environmental fields, including air and noise pollution control, solid waste process-
ing and resource recovery, physicochemical treatment processes, biological treat-
ment processes, biosolids management, water resources, natural control processes,
radioactive waste disposal and thermal pollution control; and (2) to employ a multi-
media approach to environmental pollution control since air, water, soil and energy
are all interrelated.
As can be seen from the above handbook coverage, no consideration is given
to pollution by type of industry, or to the abatement of specific pollutants. Rather,
the organization of the handbook series has been based on the three basic forms in
which pollutants and waste are manifested: gas, solid, and liquid. In addition, noise
pollution control is included in the handbook series.
This particular book Volume 8, Biological Treatment Processes, is a sister book to
Volume 9, Advanced Biological Treatment Processes. Both books have been designed
to serve as comprehensive biological treatment textbooks as well as wide-ranging
reference books. We hope and expect they will prove of equal high value to advanced
Preface vii
undergraduate and graduate students, to designers of water and wastewater
treatment systems, and to scientists and researchers. The editors welcome comments
from readers in all of these categories.
This book Volume 8, Biological Treatment Processes, covers the subjects, of funda-
mental biological concepts, wastewater land application subsurface application, sub-
merged aeration, surface aeration, spray aeration, activated sludge processes, pure
oxygen activated sludge process, waste stabilization ponds, lagoons, trickling filters,
rotating biological contactors, sequencing bath reactors, oxidation ditch, biological
nitrification, denitrification, anaerobic digestion, aerobic digestion, composting, ver-
micomposting, odor control and VOC control. The sister book Volume 9, Advanced

Biological Treatment Processes, covers the subjects of biological process kinetics,
vertical shaft bioreactors, aerobic granulation technology, membrane bioreactors, SBR
nutrient removal, simultaneous nitrification and denitrification, single-sludge nutri-
ent removal system, nitrogen removal process selection, column bioreactor, upflow
sludge blanket filtration, anaerobic lagoons, storage ponds, vertical shaft digestion,
flotation, biofiltration, biosolids land application, deep-well injection, natural biolog-
ical processes, emerging suspended growth biological processes, emerging attached
growth biological processes and environmental engineering conversion factors.
The editors are pleased to acknowledge the encouragement and support received
from their colleagues and the publisher during the conceptual stages of this endeavor.
We wish to thank the contributing authors for their time and effort, and for having
patiently borne our reviews and numerous queries and comments. We are very
grateful to our respective families for their patience and understanding during some
rather trying times. The editors are especially indebted to Dr. Nazih K. Shammas of
the Lenox Institute of Water Technology, Massachusetts, for his services as Consulting
Editor of this Volume.
Lawrence K. Wang, Lenox, MA
Norman C. Pereira, St. Louis, MO
Yung-Tse Hung, Cleveland, OH
Contents
Preface v
Contributors xxi
1. Fundamental Concepts for Environmental Processes
Mary Lou Bungay and Henry R. Bungay 1
1. Introduction 1
2. The Cell 2
3. Biochemistry 3
3.1. Important Compounds 3
3.2. Photosynthesis 8
3.3. Chemosynthesis 9

3.4. Respiration 9
3.5. Nutrition 11
4. Microbiology 12
4.1. Bacteria 12
4.2. Archaea 13
4.3. Algae 13
4.4. Protozoa 13
4.5. Fungi 14
4.6. Viruses 15
4.7. Other 15
5. Ecology 15
5.1. Structure of the Ecosystem 16
5.2. Biogeochemical Cycles 17
5.3. Interspecies Relationships 18
5.4. Population Dynamics 19
6. Physical and Biological Factors in Waste Treatment Ecosystems 21
6.1. Chemical Composition of the Medium 21
6.2. Indices of Pollution 22
6.3. Flow Rates and Concentration 23
6.4. Surfaces and Substrata 23
6.5. Nutritional Shifts 23
6.6. Biological Interactions 24
6.7. Ecological Succession 25
7. Conclusions 26
References 27
2. Treatment by Application Onto Land
Donald B. Aulenbach and Nicholas L. Clesceri 29
1. Introduction 29
1.1. Scope 29
1.2. Philosophy 30

2. Types 32
2.1. Surface Spreading 32
2.2. Slow Rate 32
ix
x Contents
2.3. Rapid Infiltration—Percolation 35
2.4. Vegetative Cover vs. Bare Ground 36
2.5. Final Residence of Liquid 37
2.6. Chlorination 37
3. Processes 37
3.1. Physical 38
3.2. Physical-Chemical 40
3.3. Chemical 41
3.4. Biological 42
3.5. Process Applications 45
4. Design 52
4.1. Preliminary Studies 52
4.2. Application Rates 53
4.3. Distribution Facilities 53
4.4. Monitoring 54
5. Evaluation 55
5.1. Effectiveness 55
5.2. Applicability 56
5.3. Cost 57
5.4. Ease of Design for Various Conditions 58
Nomenclature 69
References 69
3. Treatment by Subsurface Application
Nicholas L. Clesceri, Donald B. Aulenbach, and James F. Roetzer 75
1. Introduction 75

2. Theory 76
2.1. Pretreatment in a Tank 76
2.2. Subsurface Disposal 79
3. Design 88
3.1. General Considerations 89
3.2. Septic Tank Design 90
3.3. Aerobic Tank Design 91
3.4. Conventional Tile Field 92
3.5. Aerobic Tile Field 96
3.6. Seepage Pit 99
3.7. Institutional and Multiple Dwelling Systems 100
3.8. Construction 101
4. State of the Art 101
4.1. Tank Treatment 101
4.2. Effluent Disposal 102
4.3. Nutrient Removal 102
4.4. Innovative Design 103
4.5. Maintenance 103
4.6. Restoration 104
5. Conclusions 105
6. Cost Estimation 105
7. Sample Design Problems 106
Nomenclature 109
References 109
Appendix 112
Contents xi
4. Submerged Aeration
Jerry R. Taricska, Jerry Y. C. Huang, J. Paul Chen,
Yung-Tse Hung, and Shuai-Wen Zou 113
1. Introduction 113

2. Aeration Performance Evaluation 114
2.1. Hydraulic Regimes of Performance Evaluation 115
2.2. Means of Deoxygenation 116
2.3. Oxygen Saturation Concentration 117
2.4. Data Analysis and Interpretation 119
3. Submerged Aeration Systems 123
3.1. System Components 123
3.2. Major Types of Submerged Aerators 125
4. Design Applications 133
4.1. Types of Design Problems 133
4.2. Case Study Example 134
5. Recent Development in Submerged Aeration 139
Nomenclature 145
References 147
5. Surface and Spray Aeration
Jerry R. Taricska, J. Paul Chen, Yung-Tse Hung,
Lawrance K. Wang, and Shuai-Wen Zou 151
1. Introduction 151
2. Fundamental Concepts 152
2.1. Equilibrium 152
2.2. Gas Solubility 153
2.3. Molecular Diffusion 155
2.4. Turbulent Mixing 156
2.5. Air-Water Interface 157
3. Theories of Gas Transfer 157
3.1. Mass Transfer Equation 157
3.2. Two-Film Theory 158
3.3. Penetration Model 160
3.4. Film-Penetration Model 161
3.5. Surface Renewal-Damped Eddy Diffusion Model 162

3.6. Turbulent Diffusion Model 163
3.7. Other Models 163
3.8. Comparison of Gas Transfer Coefficients 163
3.9. Gas-Liquid Relation 164
4. Aeration Equation 165
4.1. Significance of the Aeration Equation 165
4.2. Influencing Factors 166
4.3. Natural Reaeration 167
5. Surface Aeration 173
5.1. Introduction 173
5.2. Types of Surface Aerators 174
5.3. Techniques for Surface Aerator Performance Test 175
5.4. Surface Aerator Design 180
5.5. Artificial Instream Aeration 180
xii Contents
6. Spray Aeration 184
6.1. Introduction 184
6.2. Types of Spray Aerators 185
6.3. Spray Aeration Applications 188
6.4. Spray Aerator Design 190
7. Recent Development in Surface and Spray Aeration 196
Nomenclature 201
References 203
6. Activated Sludge Processes
Lawrence K. Wang, Zucheng Wu, and Nazih K. Shammas 207
1. Concepts and Physical Behavior 208
1.1. Definition of Process 208
1.2. Principles of Biological Oxidation 209
1.3. Energy Flow 214
1.4. Synthesis and Respiration 216

2. System Variables and Control 217
2.1. Kinetics of Sludge Growth, and Substrate Removal 218
2.2. Process Variables, Interactions and their Significance in Process Operation and Performance 222
2.3. Aeration Requirements 226
2.4. Temperature Effect 227
3. System Modifications and Design Criteria 228
3.1. Conventional Activated Sludge Process 228
3.2. Step Aeration Process 230
3.3. Complete Mix Process 230
3.4. Extended Aeration Process 231
3.5. Contact Stabilization Process 231
3.6. Kraus Process 233
3.7. Design Criteria 233
3.8. Other Processes 237
4. Computer Aid in Process Design and Operation 238
4.1. Prediction of Performance 238
4.2. Computer Program for Process Design 241
4.3. Computer Aid in Process Operation 242
5. Practice and Problems in Process Control 245
5.1. Wasting Sludge, Feedback and Feed Forward Control 245
5.2. Bulking of Sludge and Rising of Sludge 247
6. Capital and Operating Cost 248
6.1. Traditional Cost Estimates 249
6.2. Worksheet for Cost Estimates 251
6.3. Improvements of Cost Estimation Techniques 251
7. Important Developments 253
7.1. High Rate Adsorption-Biooxidation Process 253
7.2. Carrier-Activated Sludge Processes 254
7.3. Secondary Flotation Process 263
7.4. Nitrification and Denitrification 264

7.5. Membrane Bioreactor 265
7.6. Reduction of Excess Sludge 266
8. Design Examples 266
Acknowledgement 270
Nomenclature 270
Definition of Terms; Casso Program 272
References 272
Appendices 279
Contents xiii
7. Pure Oxygen Activated Sludge Process
Nazih K. Shammas and Lawrence K. Wang 283
1. Introduction 283
2. Pure Oxygen Activated Sludge, Covered 284
2.1. Process Description 284
2.2. Applications 285
2.3. Design Criteria 286
2.4. Performance 286
2.5. Energy Requirements 287
2.6. Costs 288
3. Pure Oxygen Activated Sludge, Uncovered 289
3.1. Description 289
3.2. Applications 291
3.3. Design Criteria 291
3.4. Performance 291
3.5. Energy Requirements 291
3.6. Costs 293
4. Design Considerations 294
4.1. Input Data 294
4.2. Design Parameters 295
4.3. Design Procedure 295

4.4. Output Data 304
5. Design Example 304
Nomenclature 310
References 311
Appendix 314
8. Waste Stabilization Ponds and Lagoons
Nazih K. Shammas, Lawrence K. Wang, and Zucheng Wu 315
1. Concepts and Physical Behavior 316
1.1. Pond Ecology and Process Reactions 316
1.2. Biology of Stabilization Ponds 323
1.3. Classification of Stabilization Ponds 326
2. System Variables and Control 327
2.1. Kinetics of Substrate Removal 327
2.2. Oxygen Supply 331
2.3. Temperature Effect 334
2.4. Detention Time 335
3. Design Criteria 336
3.1. Design Parameters 336
3.2. Inlet Structures 336
3.3. Outlet Structures 336
3.4. Transfer Pipes 338
3.5. Berm Design 338
3.6. Bottom Preparation 339
4. Practice and Problems in Process Control 339
4.1. Staging of Ponds 339
4.2. Pond Recirculation 339
4.3. Pond Mixing and Aeration 340
4.4. Odor Control 342
4.5. Algae Removal 343
4.6. Insect Control 343

5. Capital and Operating Costs 345
xiv Contents
6. Developments in Ponds Applications 349
6.1. Nutrient Removal and Controlled Eutrophication 349
6.2. Integrated Anaerobic-Facultative-Aerobic Pond Systems 350
6.3. Activated Sludge Process Integration 352
6.4. Integrated Duckweed and Stabilization Pond 352
6.5. Deep Self-regeneration and Anoxic Waste Stabilization Ponds 353
6.6. Algae and Phosphorus Removal by Induced Air Flotation 354
6.7. Combination with Constructed Wetlands 355
6.8. Synopsis of Major Developments 356
7. Examples of Process Design 356
Acknowledgement 363
Nomenclature 364
References 365
Appendix 370
9. Trickling Filters
Lawrence K. Wang, Zucheng Wu, and Nazih K. Shammas 371
1. Introduction 372
1.1. Process Description of Attached Growth Systems 372
1.2. Historical Development and Applicability of Attached Growth Systems 374
1.3. Microbiology and Ecology 376
2. Theories and Mechanisms 378
2.1. Transfer of Oxygen in Slime Layer and Liquid Film 378
2.2. Transfer of Substrate in Liquid Film and Slime Layer 379
3. Types of Trickling Filters 381
3.1. General Description 381
3.2. Low-Rate, High-Rate, and Super-Rate Filters 381
3.3. Single- and Multi-Stage Trickling Filter Plants 386
4. Performance Models and Design Procedures 387

4.1. National Research Council Models 387
4.2. Velz Model 389
4.3. Upper Mississippi River – Great Lakes Board Model 389
4.4. Howland Models 390
4.5. Eckenfelder Models 390
4.6. Galler and Gotaas Model 391
4.7. Biofilm Model 392
4.8. US Army Design Formulas 392
4.9. US Environmental Protection Agency Model 393
5. Design and Construction Considerations 394
6. Process Control Considerations 395
7. Energy Considerations 398
8. Application, Performance, and Reliability 399
9. Limitations and Environmental Impact 399
10. Recent Development of Trickling Filters 400
10.1. Treatment of Toxic and Volatile Organic Contaminants 400
10.2. Metals and Biological Nitrogen Removal 400
10.3. Structure of Biofilms and Characterization of Filter 401
10.4. Upgrading and Retrofitting 402
11. Design Examples 403
Acknowledgement 427
Nomenclature 427
References 428
Contents xv
10. Rotating Biological Contactors
Lawrence K. Wang, Zucheng Wu, and Nazih K. Shammas 435
1. Introduction 435
2. Factors Affecting Performance and Design 437
2.1. Microorganisms and Environmental Factors 437
2.2. Media Selection and Arrangement 437

2.3. Loadings and Hydraulic Parameters 438
3. Performance Models and Design Procedures 439
3.1. US Environmental Protection Agency Model 439
3.2. Modified US Environmental Protection Agency Model 439
3.3. Manufacturer’s Design Procedures 440
4. Process Control Considerations 442
5. Application, Performance and Reliability 445
6. Limitations and Environmental Impact 446
7. Recent Developments in RBC 446
7.1. Biodegradation of Hydrocarbon 446
7.2. Bioremediation of Heavy Metals 446
7.3. Denitrification 447
7.4. Improvement of RBC Design 447
7.5. Domestic Wastewater Treatment and Purification 448
8. Design Examples 448
Acknowledgement 456
Nomenclature 456
References 456
11. Sequencing Batch Reactors
Lawrence K. Wang and Yang Li 459
1. Historical Development and General Process Descriptions 460
1.1. All Sequencing Batch Reactor Processes 460
1.2. Physicochemical SBR Process Involving Sedimentation Clarification 460
1.3. Aerobic-Anoxic Biological SBR Process Involving Sedimentation Clarification 460
1.4. Aerobic-Anoxic Biological DAF-SBR Process Involving Flotation Clarification 461
1.5. Physicochemical DAF-SBR Process Involving Flotation Clarification 462
1.6. Biological Membrane-Bioreactor-(MBR-SBR) Process 462
1.7. Biological Anaerobic SBR Process 462
1.8. Biofilm SBR Process 463
1.9. Solid Waste SBR Digestion Process 463

1.10. Ion Exchange-SBR Process 464
1.11. GAC-SBR Processes 464
1.12. PAC-SBR and PACT-SBR Processes 465
1.13. VSB-SBR and VSD-SBR Processes 465
1.14. Physicochemical Membrane-SBR Process 466
1.15. Biosolids SBR Digestion Process 466
2. Traditional SBR Process Systems 466
2.1. Traditional SBR Process Description 466
2.2. Traditional SBR Compared to Other Biological Treatment Systems 467
3. Principles and Operation of Traditional SBR Process 469
3.1. Process Principles 469
3.2. Operational Phases 469
3.3. Food to Microorganism Ratio (F:M) 471
xvi Contents
4. Process Applications 472
4.1. BOD Reduction 472
4.2. Nitrogen Removal 472
4.3. Phosphorus Removal 473
4.4. Municipal Domestic Applications 473
4.5. Industrial Applications 474
5. Process Design 474
5.1. Flow and Cycle Time 474
5.2. Process Phase Design 474
5.3. Process Modifications 478
5.4. Decanter System Design 478
5.5. Skimming System Design 481
5.6. Energy Input Optimization 481
5.7. Three Design Steps 482
6. Summary and Conclusions 482
6.1. General Summary 482

6.2. Performance Evaluation 483
6.3. Cost Evaluation 485
6.4. Operation Evaluation 485
6.5. Online Information 487
7. Design Examples 487
Nomenclature 508
References 508
12. Oxidation Ditch
Nazih K. Shammas and Lawrence K. Wang 513
1. Introduction 514
2. Process Description 514
3. Applicability 516
4. Advantages and Disadvantages 516
5. Design Criteria 517
5.1. Solids Retention Time (SRT) 517
5.2. BOD Loading 517
5.3. Hydraulic Retention Time 517
6. Performance 518
6.1. Casa Grande Water Reclamation Facility 518
6.2. Edgartown, Massachusetts WWTP 518
7. Package Oxidation Ditch Plants 519
7.1. Description 519
7.2. Applicability 520
7.3. Advantages and Disadvantages 520
7.4. Design Criteria 520
7.5. Performance 521
7.6. Costs 522
8. Operation and Maintenance 522
8.1. Residuals Generated 522
8.2. Operating Parameters 522

9. Design Considerations 522
9.1. Input Data 522
9.2. Design Parameters 523
9.3. Design Procedure 523
9.4. Output Data 526
10. Costs 527
11. Design Example 530
Contents xvii
Nomenclature 534
References 535
Appendix 538
13. Biological Nitrification and Denitrification Processes
Yue-Mei Lin, Joo-Hwa Tay, Yu Liu, and Yung-Tse Hung 539
1. Introduction 539
2. Fundamentals of Nitrification 540
2.1. Stoichiometry 540
2.2. Metabolism 541
2.3. Methods for Nitrifier Identification 543
2.4. Nitrification Kinetics 546
2.5. Factors Affecting Nitrification 547
3. Fundamentals of Denitrification Process 550
3.1. Microbiology 550
3.2. Stoichiometry 551
3.3. Metabolisms 551
3.4. Methods for Identifying Denitrifiers 553
3.5. Procedures for Measuring Denitrification 554
3.6. Denitrification Kinetics 554
3.7. Factors Influencing Denitrification 554
4. Modeling of Nitrification and Denitrification 556
4.1. Suspended-Growth Models 556

4.2. Fixed-Growth Models 557
5. Biological Nitrification and Denitrification Processes 557
5.1. Nitrification Processes 558
5.2. Biological Denitrification Process 562
6. Commercialized Nitrogen Removal Processes 566
7. New Biology for Nitrogen Removal 568
7.1. Nitrite Route 568
7.2. Aerobic Denitrification 568
7.3. Autotrophic Denitrification 569
7.4. Heterotrophic Nitrification 569
7.5. Anaerobic Ammonium Oxidation (Anammox) 570
7.6. New Metabolisms 571
8. New Findings of Bacteria for Nitrogen Removal 573
9. Design Example 573
Nomenclature 578
References 580
14. Anaerobic Digestion
Jerry R. Taricska, David A. Long, J. Paul Chen, Yung-Tse Hung,
and Shuai-Wen Zou 589
1. Introduction 589
2. Theory 591
2.1. Nature of Organic Wastes 591
2.2. Biochemistry and Microbiology of the Anaerobic Process 591
2.3. Reactor Configurations 593
2.4. Organic Loading Parameters 595
2.5. Time and Temperature Relationships 596
2.6. Nutrient Requirements 597
2.7. Gas Production and Use 598
xviii Contents
3. Design Practice 599

3.1. Anaerobic Treatability Studies 599
3.2. Anaerobic Reactor Design and Sizing 601
3.3. Tank Construction and System Components 604
3.4. System Equipment and Appurtenances 605
3.5. Gas Use 615
3.6. Sludge Pumping and Piping Considerations 615
4. Management of Digestion 616
4.1. Control of Sludge Feed 616
4.2. Withdrawal of Sludge and Supernatant 616
4.3. Maintenance of Reactor Stability 617
4.4. Digester Performance Criteria 617
5. Capital and Operating Costs 618
5.1. General 618
5.2. Items Included in Cost Estimates 618
6. Design Examples 619
6.1. Example Using Standards Design 619
6.2. Example Using Solids Loading Factor 621
6.3. Example Using Modified Anaerobic Contact Process 624
7. Recent Development in Anaerobic Process 625
Nomenclature 631
References 631
15. Aerobic Digestion
Nazih K. Shammas and Lawrence K. Wang 635
1. Introduction 636
2. Process Description 636
2.1. Microbiology 636
2.2. Advantages 637
2.3. Disadvantages 637
3. Process Variations 637
3.1. Conventional Semi-Batch Operation 637

3.2. Conventional Continuous Operation 638
3.3. Autothermal Thermophilic Aerobic Digestion (Using Air) 638
3.4. Autothermal Thermophilic Aerobic Digestion (Using Oxygen) 639
4. Design Considerations 640
4.1. Temperature 640
4.2. Solids Reduction 640
4.3. Oxygen Requirements 642
4.4. Mixing 643
4.5. pH Reduction 643
4.6. Dewatering 643
5. Process Performance 644
5.1. Total Volatile Solids Reduction 644
5.2. Supernatant Quality 644
6. Process Design 645
6.1. Input Data 645
6.2. Design Parameters 646
6.3. Design Procedure 646
6.4. Output Data 649
7. Cost 649
7.1. Capital Cost 649
7.2. Operation and Maintenance Cost 650
Contents xix
8. Recent Developments and Summary 651
8.1. Recent Developments 651
8.2. Summary 652
9. Design Examples 653
Nomenclature 660
References 661
Appendix 667
16. Biosolids Composting

Nazih K. Shammas and Lawrence K. Wang 669
1. Introduction 670
2. Applicability and Environmental Impact 671
3. Compost Quality 674
4. Process Description 675
4.1. Moisture 676
4.2. Temperature 677
4.3. pH 678
4.4. Nutrient Concentration 678
4.5. Oxygen Supply 678
5. Design Criteria and Procedures 678
5.1. Compost Processes with no External Bulking Agent 681
5.2. Compost Processes Using External Bulking Agent 683
6. Windrow Process 684
6.1. Methodology and Design 684
6.2. Energy Requirements 687
6.3. Public Health and Environmental Impacts 687
7. Aerated Static Pile Process 689
7.1. Process Description 689
7.2. Individual Aerated Piles 690
7.3. Extended Aerated Piles 691
7.4. Oxygen Supply 692
7.5. Bulking Agent 692
7.6. Energy Requirements 693
7.7. Public Health and Environmental Impacts 693
8. In-Vessel Composting System 694
8.1. Process Description 694
8.2. Advantages and Disadvantages 698
8.3. Applicability 699
9. Costs 700

10. Design Examples 701
10.1. Design Example 1-Windrow Process 701
10.2. Design Example 2-Extended Aerated Pile System 704
Nomenclature 709
References 709
Appendix 714
17. Vermicomposting Process
Lawrence K. Wang, Yung-Tse Hung, and Kathleen Hung Li 715
1. Introduction 715
1.1. Summary 715
1.2. Process Description 716
2. Technology Development 716
xx Contents
3. Problems and Technology Breakthrough 720
3.1. Introduction 720
3.2. Problems 720
3.3. Progress in Vermicomposting outside the U.S.A 722
4. Pioneers, Current Status and Resources 723
4.1. Pioneers and Current Status 723
4.2. Resources 725
5. Process Design Considerations 726
5.1. Process Adoption and Advantages 726
5.2. Process Operation and Troubleshooting 726
5.3. Process Limitations 727
5.4. Process Design Criteria 728
6. Process Application Examples 728
7. Future Development and Direction 729
References 729
18. Biological Odor and VOC Control Process
Gregory T. Kleinheinz and Phillip C. Wright 733

1. Introduction 733
2. Types of Biological Air Treatment Systems 735
2.1. General Descriptions 735
2.2. Novel or Emerging Designs 736
3. Operational Considerations 739
3.1. General Operational Considerations 739
3.2. Biofilter Media 741
3.3. Microbiological Considerations 743
3.4. Chemical Considerations 744
3.5. Comparison to Competing Technologies 746
4. Design Considerations/Parameters 747
4.1. Pre-design 747
4.2. Packing 747
5. Case Studies 748
5.1. High Concentration 2-Propanol (IPA) and Acetone 748
5.2. General Odor Control at a Municipal Wastewater Treatment Facility 748
6. Process Control and Monitoring 754
7. Limitations of the Technology 755
8. Conclusions 755
Nomenclature 756
References 756
Appendix: Conversion Factors for Environmental Engineers
Lawrence K. Wang 759
Index 805
Contributors
DONALD B. AULENBACH, PhD, PE, DEE • Professor, Lenox Institute of Water Technology,
Lenox, MA and Emeritus Professor, Rensselaer Polytechnic Institute, Troy, NY
M
ARY LOU BUNGAY, M.S • Rensselaer Polytechnic Institute, Troy, NY
H

ENRY R. BUNGAY, PhD • Professor, Department of Chemical Engineering, Rensselaer
Polytechnic Institute, Troy, NY
J. P
AUL CHEN, PhD • Associate Professor, Department of Chemical and Biomolecular
Engineering, National University of Singapore, Singapore
NICHOLAS L. CLESCERI, PhD • Emeritus Professor, Department of Civil and Environ-
mental Engineering, Rensselaer Polytechnic Institute, Bolton Landing, NY
J
ERRY Y. C. HUANG, PhD, PE • President, Huang & Associates, Carmichael, CA
Y
UNG-TSE HUNG, PhD, PE, DEE • Professor, Department of Civil and Environmental
Engineering, Cleveland State University, Cleveland, OH
G
REGORY T. KLEINHEINZ, PhD • Assistant Professor, Department of Biology and Micro-
biology, University of Wisconsin – Oshkosh, Oshkosh, WI
KATHLEEN HUNG LI, MS • Senior Technical Writer, NEC Unified Solutions, Inc., Irving,
TX
Y
AN LI, PE, MS • Senior Sanitary Engineer, State of Rhode Island, Office of Waste Manage-
ment, Department of Environmental Management, Providence, RI
YUE-MEI LIN • Research Scholar, School of Civil and Environmental Engineering,
Nanyang Technological University, Singapore
Y
U LIU, PhD • Assistant Professor, School of Civil and Environmental Engineering,
Nanyang Technological University, Singapore
DAVID A. LONG, PhD • Emeritus Professor, Department of Civil Engineering, Pennsylva-
nia State University, University Park, PA
N
ORMAN C. PEREIRA, PhD • Monsanto Company (retired), St. Louis, MO
J

AMES F. ROETZER, PhD • Alternative Environmental Strategies, LLC, Williamsville, NY
NAZIH K. SHAMMAS, PhD • Professor and Environmental Engineering Consultant, Ex-
Dean and Director, Lenox Institute of Water Technology, Lenox, MA and Krofta Engi-
neering Corporation, Lenox, MA
J
ERRY R. TARICSKA, PhD, PE, DEE • Senior Environmental Engineer/Associate, Hole
Montes, Inc., Naples, FL
JOO-HWA TAY , PhD, PE • Professor and Division Head, School of Civil and Environmental
Engineering, Nanyang Technological University, Singapore
xxi
xxii Contributors
L
AWRENCE K. WANG, PhD, PE, DEE • Ex-Dean and Director, Lenox Institute of Water
Technology, Lenox, MA; Assistant to the President (retired) Krofta Engineering Corpora-
tion, Lenox, MA and VP, Zorex Corporation, Newtonville, NY
P
HILLIP C. WRIGHT, PhD • Reader in Chemical Engineering and EPSRC Advanced
Research Fellow, Department of Mechanical and Chemical Engineering, Heriot-Watt
University, Riccarton Edinburgh, Scotland
Z
UCHENG WU, PhD • Professor, Department of Environmental Engineering, Zhejiang
University, Hangzhou, China
SHUAI-WEN ZOU, M. Eng • Research Scholar, Department of Chemical and Biomolecular
Engineering, National University of Singapore, Singapore
1
Fundamental Concepts for Environmental Processes
Mary Lou Bungay and Henry R. Bungay
CONTENTS
INTRODUCTION
THE CELL

BIOCHEMISTRY
MICROBIOLOGY
ECOLOGY
PHYSICAL AND BIOLOGICAL FACTORS IN WASTE TREATMENT
ECOSYSTEMS
CONCLUSIONS
REFERENCES
Abstract Living microorganisms consume organic material in wastes, and use its energy
to sustain normal activities, to grow, and to reproduce. A biological process, either natural
or artificial, involves biochemical reactions, nutrient balance, microbial population balance,
and waste disposal. This chapter introduces biological concepts for environmental control
processes. The specific topics covered include: cellular interactions, biochemistry, photo-
synthesis, chemosynthesis, respiration, microbiology, ecology, ecosystem, waste treatment,
pollution indices, and biological interactions.
Key Words Biological process
r
cell
r
biochemistry
r
photosynthesis
r
chemosynthesis
r
respira-
tion
r
environmental microbiology
r
ecology

r
waste treatment
r
ecosystems.
1. INTRODUCTION
Sound foundations with understanding of reactions and processes are essential to envi-
ronmental scientists and engineers for determining the fate of pollutants that reach natural
systems and for the improvement of waste treatment. Most of the economically effective
methods for destroying wastes use normal cellular processes for breakdown of many types
From: Handbook of Environmental Engineering, Volume 8: Biological Treatment Processes
Edited by: L. K. Wang et al.
c
 The Humana Press, Totowa, NJ
1
2 M. L. Bungay and H. R. Bungay
of organic wastes. Concepts from biochemistry and biology that are introduced in this chapter
apply to specific treatment processes covered in subsequent chapters.
Living cells consume organic material and use its energy to sustain normal activity, to
grow, and to reproduce. Some of the cells’ wastes—water, carbon dioxide, and minerals—
are environmentally acceptable. The cellular mass, however, is itself pollutional because its
discharge into streams and lakes would provide nutrients for microorganisms that consume
oxygen; thus fish could suffocate. Biological waste treatment usually strives to produce a
minimal amount of cellular material that is easily collectible for disposal.
Proper regard for basic scientific principles provides a basis for achieving high efficiency
for treatment processes. Although understanding is incomplete because of the great complex-
ity of bioprocesses containing ill-defined nutrients and many different organisms, there have
been practical results in terms of design and processing through considering biochemistry and
biology.
2. THE CELL
In a scientific context, life is most adequately described in terms of activity. An entity that

is organized so as to maintain a definite structure, respond to stimuli, grow, reproduce its own
kind, and acquire the energy needed for all of these activities is generally regarded as a living
organism. The cell is the structural and functional unit of life. In multicellular organisms, cells
are often highly specialized and function in cooperation with other specialized cells. But many
organisms are, in fact, free-living single cells.
Although cells differ in size, shape, and specialization, all have the same basic structure.
Every cell is composed of cytoplasm, a colloidal system of large organic molecules integrated
with a complex solution of smaller organic molecules and inorganic salts. The cytoplasm is
bounded by a semielastic, selectively permeable cell membrane that controls the movement of
molecules into and out of the cell. Threadlike chromosomes suspended in the cytoplasm bear a
linear arrangement of genes. Information carried on the genes controls every cellular activity,
and, as the units of heredity, genes determine the characteristics of cells from one generation
to the next.
In most cells, the chromosomes are surrounded by a cell membrane to form a conspicuous
nucleus. A number of other organized intracellular structures serve as specialized sites for
cellular activities. Certain cells of green plants, for example, contain chloroplasts that play
an essential role in photosynthesis. Chlorophyll and other associated photosynthetic pigments
are contained within the layered membranous structure of the chloroplast. Cells that possess
organized nuclei are eukaryotic.
In bacteria, archea, and cyanobacteria (formerly called blue-green algae) the chromo-
somes are not surrounded by a membrane, and there is little apparent subcellular orga-
nization. The chlorophyll of cyanobacteria is associated with loosely arranged mem-
branes within the cytoplasm; bacterial chlorophyll, when present, is located in vesicular
chromatophores. Because they lack a discrete nucleus, these organisms are said to be
prokaryotic.
Fundamental Concepts 3
Many cells are surrounded by an outer covering external to the cell membrane. Plant cells,
bacteria, and blue-green algae are protected by rigid cell walls. Certain algae and protozoa are
surrounded by siliceous shells.
The distinctive and sometimes elaborate shape exhibited by many unicellular organisms is

an inherited characteristic. However, evidence gathered in the culture of isolated cells suggests
that in multicellular organisms, cell shape is environmentally determined.
The smallest known cell, pleuropneumonia-like organism (PPLO) is approximately
0.1 micron (µm) in diameter, and the largest, the ostrich egg is about 150 mm in diameter.
Most cells, however, have diameters of 0.5 to 40 µm. Because all of the substances required
by the cell must enter through the surface membrane, one of the most important limitations
to cell size is the ratio of surface to volume. The ease with which a given substance passes
through the membrane, its rate of diffusion through the cytoplasm, and the rate at which it
is used by the cell have a bearing on cell size. Another important factor in cell size is the
proximity of the genes, which continuously monitor cellular activity; as cell size increases,
interaction with remote parts of the cell diminishes.
3. BIOCHEMISTRY
3.1. Important Compounds
Despite the obvious diversity of living forms, there is a surprising consistency in the
chemical nature of all living things. The main categories of biochemicals in virtually every
living system are carbohydrates, lipids, proteins, and nucleic acids.
Carbohydrates are composed of carbon, hydrogen, and oxygen, commonly in a ratio of
1:2:1 (C
n
H
2n
O
n
). Carbohydrates that will not form simpler compounds upon the addition
of water (hydrolysis) are called simple sugars, or monosaccharides. Simple sugars contain
from three to seven carbons; the most common sugar is glucose, a six-carbon molecule. With
the removal of a molecule of water (condensation), two simple sugars may combine to form
a disaccharide. For example, the disaccharide maltose contains two molecules of glucose
(Figure 1.1); the condensation of glucose and fructose, another six-carbon sugar, produces
sucrose, or cane sugar.

In the same manner a large number of monosaccharide units may be joined to form
polysaccharides such as starch, glycogen, or cellulose (Figure 1.2). Starch and glycogen are
energy storage compounds. Cellulose is a major structural material in plants.
Lipids are also made up of carbon, hydrogen, and oxygen. Fats are a very common form
of lipid composed of a molecule of glycerol and three fatty acid molecules. Fatty acids
are characterized by a long carbon chain and, like all organic acids, by a carboxyl group,
COOH. Figure 1.3 shows the general configuration of a triglyceride in which R, R
′
, and R
′′
represent the carbon chains of three different fatty acids.
Palmitic and oleic acids are examples of two common fatty acids (Figure 1.4). Naturally
occurring fats are mixtures of compounds of glycerol with several different fatty acids. Fats
serve as storage compounds for reserve energy.