Wastewater Treatment Plant Design Handbook

WASTEWATER TREATMENT PLANT DESIGN HANDBOOK

2012 Water Environment Federation 601 Wythe Street Alexandria, VA 22314-1994 USA

Wastewater Treatment Plant Design Handbook Copyright © 2012 by the Water Environment Federation. All Rights Reserved. Permission to copy must be obtained from WEF. Water Environment Research, WEF, and WEFTEC are registered trademarks of the Water Environment Federation®. ISBN 978-1-57278-271-6

IMPORTANT NOTICE The material presented in this publication has been prepared in accordance with generally recognized engineering principles and practices and is for general information only. This information should not be used without first securing competent advice with respect to its suitability for any general or specific application. The contents of this publication are not intended to be a standard of the Water Environment Federation® (WEF) and are not intended for use as a reference in purchase specifications, contracts, regulations, statutes, or any other legal document. No reference made in this publication to any specific method, product, process, or service constitutes or implies an endorsement, recommendation, or warranty thereof by WEF. WEF makes no representation or warranty of any kind, whether expressed or implied, concerning the accuracy, product, or process discussed in this publication and assumes no liability. Anyone using this information assumes all liability arising from such use, including but not limited to infringement of any patent or patents.

About WEF Formed in 1928, the Water Environment Federation® (WEF®) is a not-for-profit technical and educational organization with members from varied disciplines who work towards WEF’s vision to preserve and enhance the global water environment. For information on membership, publications, and conferences, contact Water Environment Federation 601 Wythe Street Alexandria, VA 22314-1994 USA (703) 684-2400 http://www.wef.org

Prepared by the Wastewater Treatment Plant Design Handbook Task Force of the Water Environment Federation Hannah T. Wilner, P.E., Chair James S. Bays Lucas Botero, P.E., BCEE Peter Burrowes, P.Eng. Mary Kay Camarillo, Ph.D., P.E. Peter V. Cavagnaro, P.E., BCEE Rhodes R. Copithorn, P.E., BCEE Timur Deniz, Ph.D., P.E. Leon S. Downing, Ph.D., P.E. Sarah Hubbell Thomas E. Jenkins, P.E. Samuel S. Jeyanayagam, Ph.D., P.E., BCEE Kenneth Knickerbocker, P.E., R.L.S. Terry L. Krause, P.E., BCEE

Ting Lu, Ph.D. Eric Lynne Maritza A. Macias-Corral, Ph.D. William C. McConnell, P.E. Heather M. Phillips, P.E. Christopher Pizarro Joseph C. Reichenberger, P.E., BCEE Nalin Sahni, E.I., LEED Green Assoc. Julian Sandino, P.E., Ph.D. Paul J. Schuler, P.E. Stephanie L. Spalding, P.E. K.C. “Kumar” Upendrakumar, P.E., BCEE Thor Young, P.E., BCEE

Under the Direction of the Municipal Design Subcommittee of the Technical Practice Committee 2012 Water Environment Federation 601 Wythe Street Alexandria, VA 22314–1994 USA http://www.wef.org

Manuals of Practice of the Water Environment Federation® The WEF Technical Practice Committee (formerly the Committee on Sewage and Industrial Wastes Practice of the Federation of Sewage and Industrial Wastes Associations) was created by the Federation Board of Control on October 11, 1941. The primary function of the Committee is to originate and produce, through appropriate subcommittees, special publications dealing with technical aspects of the broad interests of the Federation. These publications are intended to provide background information through a review of technical practices and detailed procedures that research and experience have shown to be functional and practical. Water Environment Federation Technical Practice Committee Control Group Jeanette Brown, P.E., BCEE, D. WRE, Chair Eric Rothstein, Vice-Chair, Publications Stacy J. Passaro, P.E., BCEE, Vice-Chair, Distance Learning R. Fernandez, Past Chair J. Bannen P. A. Bizier, P.E., BCEE K. D. Conway, P.E. R. Copithorn S. V. Dailey, P.E. E. M. Harold, P.E. M. Hines R. L. Horres D. Morgan C. A. Pomeroy, Ph.D., P.E. R. Pope A. T. Sandy K. Schnaars A. R. Shaw, P.E. J. Swift A. K. Umble, Ph.D., P.E., BCEE

Contents List of Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii List of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xv Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xix

Chapter 1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1.0

OVERVIEW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

2.0

REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Chapter 2

Raw Wastewater Characterization and Hydraulics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

1.0

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

2.0

RAW WASTEWATER CHARACTERIZATION . . . . . . . . . . . . . . . . . . . . . 4 2.1

Flow Projections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

2.2

Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

3.0

PLANT HYDRAULICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

4.0

REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Chapter 3

Preliminary Treatment . . . . . . . . . . . . . . . . . . . . . . . 13

1.0

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

2.0

SCREENING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 2.1

Screen Sizes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

2.2

Types of Screens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

3.0

GRIT REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

4.0

SEPTAGE ACCEPTANCE AND PRETREATMENT . . . . . . . . . . . . . . . . 16

5.0

EQUALIZATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

6.0

REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Chapter 4

Primary Treatment . . . . . . . . . . . . . . . . . . . . . . . . . . 21

1.0

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

2.0

SEDIMENTATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 vii

viii

Contents 3.0

HIGH-RATE CLARIFICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

4.0

FINE SCREENS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

5.0

PRIMARY SLUDGE AND SCUM COLLECTION AND REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

6.0

REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Chapter 5

Biofilm Reactor Technology and Design . . . . . . . 31

1.0

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

2.0

MOVING BED BIOFILM REACTORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

3.0

BIOLOGICALLY ACTIVE FILTERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

4.0

EXPANDED AND FLUIDIZED BED BIOFILM REACTORS . . . . . . . . . 37

5.0

ROTATING BIOLOGICAL CONTACTORS . . . . . . . . . . . . . . . . . . . . . . . 40

6.0

TRICKLING FILTERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

7.0

EMERGING BIOFILM REACTORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

8.0

REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Chapter 6

Suspended Growth Biological Treatment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

1.0

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

2.0

PROCESS CONFIGURATIONS AND TYPES . . . . . . . . . . . . . . . . . . . . . . 48

3.0

PROCESS DESIGN FOR CARBON OXIDATION AND NITRIFICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

4.0

3.1

Carbon Oxidation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

3.2

Nitrification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

PROCESS DESIGN FOR NUTRIENT CONTROL . . . . . . . . . . . . . . . . . . 52 4.1

Enhanced Biological Phosphorus Removal Processes . . . . . . . . . 52

4.2

Nitrogen Removal Processes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

4.3

Phosphorus and Nitrogen Removal Processes . . . . . . . . . . . . . . . 57

4.4

External Carbon Addition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

5.0

ANAEROBIC TREATMENT OF WASTEWATER . . . . . . . . . . . . . . . . . . . 60

6.0

MEMBRANE BIOREACTORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

7.0

OXYGEN-TRANSFER SYSTEMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

8.0

SECONDARY CLARIFICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

9.0

REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

10.0

SUGGESTED READINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

Contents

Chapter 7

Integrated Biological Treatment. . . . . . . . . . . . . . . 73

1.0

INTRODUCTION TO INTEGRATED BIOLOGICAL TREATMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

2.0

OVERVIEW OF INTEGRATED BIOLOGICAL TREATMENT SYSTEMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 2.1

Trickling Filter Solids Contact . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

2.2

Roughing Filter Activated Sludge . . . . . . . . . . . . . . . . . . . . . . . . . . 77

2.3

Activated Biofilter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

2.4

Biofilter Activated Sludge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

2.5

Trickling Filter Activated Sludge . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

2.6

Integrated Fixed-Film Activated Sludge . . . . . . . . . . . . . . . . . . . . 78

3.0

DESIGN OF CONVENTIONAL INTEGRATED BIOLOGICAL TREATMENT SYSTEMS . . . . . . . . . . . . . . . . . . . . . . . . . . 78

4.0

DESIGN OF INTEGRATED FIXED-FILM ACTIVATED SLUDGE SYSTEMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

5.0

4.1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78

4.2

Parameters Influencing Organics Removal in the Biofilm of Integrated Fixed-Film Activated Sludge Systems . . . . . . . . . . 80

4.3

Parameters Influencing Removals in the Mixed Liquor Suspended Solids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80

4.4

Empirical Design Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80

4.5

Process Kinetics Design Method (Biofilm Rate Model) . . . . . . . . 81 4.5.1

Define Range of Flux Rates . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

4.5.2

Quantify Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

4.5.3

Select Flux Rates Based on Location along Aerobic Zone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82

4.5.4

Additional Analysis To Finalize a Design . . . . . . . . . . . . . . . . 82

REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82

Chapter 8

Physical and Chemical Processes for Advanced Wastewater Treatment. . . . . . . . . . . . . . 83

1.0

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

2.0

SECONDARY EFFLUENT FILTRATION . . . . . . . . . . . . . . . . . . . . . . . . . 84 2.1

Depth Filtration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84

2.2

Compressible Medium Filtration . . . . . . . . . . . . . . . . . . . . . . . . . . 85

2.3

Disc Filtration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

ix

x

Contents 3.0

ACTIVATED CARBON ADSORPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . 87

4.0

CHEMICAL TREATMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88 4.1

Phosphorus Precipitation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

4.2

pH Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

4.3

Rapid Mixing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

4.4

Chemical Feed Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

5.0

MEMBRANE PROCESSES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93

6.0

AIR STRIPPING FOR AMMONIA REMOVAL . . . . . . . . . . . . . . . . . . . . . 95

7.0

AMMONIA REMOVAL BY BREAKPOINT CHLORINATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95

8.0

EFFLUENT REOXYGENATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95

9.0

REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

Chapter 9

Sidestream Treatment. . . . . . . . . . . . . . . . . . . . . . . . 99

1.0

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99

2.0

SIDESTREAM NITROGEN AND PHOSPHORUS REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102

3.0

REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

4.0

SUGGESTED READINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105

Chapter 10

Natural Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

1.0

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

2.0

SOIL ABSORPTION SYSTEMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108

3.0

POND SYSTEMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108

4.0

LAND TREATMENT SYSTEMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108

5.0

FLOATING AQUATIC PLANT SYSTEMS . . . . . . . . . . . . . . . . . . . . . . . 109

6.0

CONSTRUCTED WETLANDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111

7.0

REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111

Chapter 11

Disinfection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113

1.0

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113

2.0

CHLORINATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115

3.0

DECHLORINATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

4.0

ULTRAVIOLET DISINFECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

5.0

OZONE DISINFECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122

Contents 6.0

OTHER DISINFECTION METHODS . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123

7.0

REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123

Chapter 12

Solids Management, Storage, and Transport . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125

1.0

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125

2.0

SOLIDS MANAGEMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126

3.0

4.0

5.0

2.1

Regulations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126

2.2

Solids Quantities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128

2.3

Solids Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128

2.4

Pretreatment Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128

SOLIDS STORAGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128 3.1

Liquid Residuals and Biosolids . . . . . . . . . . . . . . . . . . . . . . . . . . . 128

3.2

Dewatered Cake . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129

3.3

Dried Solids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129

SOLIDS TRANSPORT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130 4.1

Liquid Residuals and Biosolids . . . . . . . . . . . . . . . . . . . . . . . . . . . 130

4.2

Dewatered Cake and Dried Solids . . . . . . . . . . . . . . . . . . . . . . . . 130

REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131

Chapter 13

Chemical Conditioning . . . . . . . . . . . . . . . . . . . . . 133

1.0

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133

2.0

INORGANIC CHEMICALS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134

3.0

ORGANIC POLYMERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134

4.0

REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137

Chapter 14

Solids Thickening. . . . . . . . . . . . . . . . . . . . . . . . . . 139

1.0

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139

2.0

GRAVITY THICKENER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140

3.0

DISSOLVED AIR FLOTATION THICKENER . . . . . . . . . . . . . . . . . . . . . 140

4.0

CENTRIFUGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142

5.0

GRAVITY BELT THICKENER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142

6.0

ROTARY DRUM THICKENER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145

7.0

COMPARISON OF THICKENING METHODS . . . . . . . . . . . . . . . . . . . 146

8.0

REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147

xi

xii

Contents

Chapter 15 1.0

Dewatering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149 1.1

Objectives of Dewatering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149

1.2

Key Process Performance Parameters . . . . . . . . . . . . . . . . . . . . . 150

2.0

CENTRIFUGES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150

3.0

BELT PRESSES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151

4.0

RECESSED-PLATE FILTER PRESSES . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153

5.0

DRYING BEDS AND LAGOONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155

6.0

ROTARY PRESSES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155

7.0

SCREW PRESSES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161

8.0

REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161

Chapter 16

Stabilization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163

1.0

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163

2.0

ANAEROBIC DIGESTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163

3.0

AEROBIC DIGESTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169

4.0

COMPOSTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172

5.0

ALKALINE STABILIZATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176

6.0

REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176

Chapter 17

Thermal Processing . . . . . . . . . . . . . . . . . . . . . . . . 179

1.0

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179

2.0

DESIGN CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183

3.0

REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183

Chapter 18

Odor Control and Air Emissions . . . . . . . . . . . . . 185

1.0

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185

2.0

DESIGN CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 188

3.0

REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 188

List of Figures 2.1

Typical hydraulic profile for influent pumping and primary treatment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

2.2

Typical hydraulic profile for an activated sludge plant . . . . . . . . . . . . . . . 9

2.3

Typical hydraulic profile for a trickling filter plant . . . . . . . . . . . . . . . . . 10

3.1

Types of grit removal chambers—(a) horizontal flow, (b) aerated, and (c) vortex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

3.2

Two equalization schemes—(a) in-line equalization and (b) side-line equalization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

4.1

Types of clarifiers—(a) rectangular with chain and flight-type collector, (b) circular, (c) stacked, and (d) plate and tube . . . . . . . . . . . . 25

6.1

Nomenclature for activated sludge flow sheet (volatile and nonvolatile represent organic and inorganic solids, respectively) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

6.2

Typical concentration patterns observed in a generic EBPR system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

6.3

Schematic illustrations of several types of anaerobic reactor configurations—(a) upflow sludge blanket, (b) biofilm fluidized bed, (c) expanded granular sludge bed, (d) anaerobic baffled reactor, (e) internal circulation, and (f) anaerobic hybrid reactor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

7.1

Combined process operations—(a) activated biofilter, (b) trickling filter–solids contact and roughing filter–activated sludge, (c) biofilter–activated sludge, and (d) trickling filter–activated sludge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

8.1

Typical phosphorus reduction with alum . . . . . . . . . . . . . . . . . . . . . . . . . 88

8.2

Membrane size comparison with wastewater constituents . . . . . . . . . . 93

9.1

Conceptual mass balance and sidestream sources for a typical wastewater treatment plant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100

11.1

Percentage of hypochlorous acid with respect to pH and temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118

15.1

Belt filter press schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152 xiii

List of Tables 2.1

Daily quantity of waste discharged by individuals on a dry-weight basis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

2.2

Typical composition of untreated domestic wastewater . . . . . . . . . . . . . . 7

2.3

Pump classification and applications in the wastewater industry . . . . . 11

3.1

Types of screens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

3.2

Headloss equations for screens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

3.3

Types of grit chambers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

3.4

Typical domestic septage characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . 18

4.1

Primary sludge characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

4.2

Types of sedimentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

4.3

Design considerations for sedimentation systems . . . . . . . . . . . . . . . . . . 27

4.4

High-rate clarification methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

4.5

Sludge and scum collection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

4.6

Sludge characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

5.1

Design criteria for denitrifying fluidized bed biofilm reactors . . . . . . . . 40

5.2

Design criteria for rotating biological contactors . . . . . . . . . . . . . . . . . . . 41

5.3

Typical operating criteria for various trickling filters . . . . . . . . . . . . . . . 43

6.1

Operational characteristics of activated sludge processes . . . . . . . . . . . . 49

6.2

Design equations for carbon oxidation . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

6.3

Design equations for nitrification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

6.4

Design parameters for activated sludge processes . . . . . . . . . . . . . . . . . . 54

6.5

Advantages and limitations of EBPR processes . . . . . . . . . . . . . . . . . . . . 56

6.6

Typical design parameters for commonly used biological phosphorus removal processes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

6.7

Suspended growth processes for nitrogen removal . . . . . . . . . . . . . . . . . 58

6.8

Combined phosphorus and nitrogen removal processes . . . . . . . . . . . . 59

6.9

Advantages and disadvantages of anaerobic treatment . . . . . . . . . . . . . 60

6.10

Recommended hydraulic detention times for UASB reactors treating domestic wastewater . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62 xv

xvi

List of Tables 6.11

Summary of the main hydraulic criteria for the design of UASB reactors treating domestic wastewater . . . . . . . . . . . . . . . . . . . . . . 62

6.12

Other design criteria for UASB reactors treating domestic wastewater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

6.13

Advantages and disadvantages of MBR systems compared to conventional activated sludge systems . . . . . . . . . . . . . . . . . . . . . . . . . 64

6.14

Typical design and operational data for MBR systems . . . . . . . . . . . . . . 65

6.15

Typical municipal MBR effluent quality . . . . . . . . . . . . . . . . . . . . . . . . . . 65

6.16

Characteristics of aeration equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

6.17

Air supply and aeration system design criteria . . . . . . . . . . . . . . . . . . . . 68

6.18

Factors that affect clarifier performance . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

6.19

Design considerations for secondary clarifiers . . . . . . . . . . . . . . . . . . . . . 70

7.1

General design criteria for IBT processes . . . . . . . . . . . . . . . . . . . . . . . . . . 79

7.2

Biofilm specific surface area for various types of media . . . . . . . . . . . . . 80

8.1

Typical filtration rates for various depth filtration technologies . . . . . . 85

8.2

Design velocities and flow volumes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

8.3

Typical carbon dosages for various column wastewater influents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87

8.4

Types of chemical feeders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92

8.5

Comparison of membrane processes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94

8.6

Summary of pretreatment alternatives for reverse osmosis membrane process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

9.1

Checklist for mainstream treatment of sidestreams . . . . . . . . . . . . . . . . 101

9.2

Sludge processing sidestream characteristics . . . . . . . . . . . . . . . . . . . . . 102

9.3

Sidestream treatment processes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103

10.1

Soil absorption systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108

10.2

Types of pond systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109

10.3

Types of land treatment systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110

11.1

Comparison of important properties for common disinfectants . . . . . 114

11.2

Equations used to express the rate of kill of microorganisms under different conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116

11.3

Chlorine dosages for proper disinfection of wastewater effluents . . . . . 117

11.4

Typical operational characteristics for UV lamps . . . . . . . . . . . . . . . . . . 120

11.5

Ozone dosages for proper disinfection of wastewater effluents based on a 15-minute contact time . . . . . . . . . . . . . . . . . . . . . . 123

12.1

Pathogen treatment processes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127

List of Tables 12.2

Sludge pump applications by principle . . . . . . . . . . . . . . . . . . . . . . . . . . 131

13.1

Typical dosages of ferric chloride and lime for dewatering wastewater solids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135

13.2.

Typical polymer dosages for thickening and dewatering . . . . . . . . . . . 136

14.1

Typical gravity thickener underflow characteristics . . . . . . . . . . . . . . . 141

14.2

Typical solids loadings for DAF thickeners . . . . . . . . . . . . . . . . . . . . . . . 142

14.3

Reported operational results for horizontal solid-bowl centrifuges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143

14.4

Typical gravity belt thickener performance . . . . . . . . . . . . . . . . . . . . . . . 144

14.5

Typical rotary drum thickener performance . . . . . . . . . . . . . . . . . . . . . . 145

14.6

Advantages and disadvantages of thickening methods . . . . . . . . . . . . 146

15.1

Typical dewatering performance data for solid-bowl centrifuges for various types of sludge and biosolids . . . . . . . . . . . . . . 151

15.2

Typical performance data for a belt filter press . . . . . . . . . . . . . . . . . . . . 153

15.3

Typical filter press dewatering performance for fixed volume press . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154

15.4

Design criteria for sand drying beds using anaerobically digested sludge without chemical conditioning . . . . . . . . . . . . . . . . . . . 156

15.5

Rotary press dewatering performance . . . . . . . . . . . . . . . . . . . . . . . . . . . 157

15.6

Installation operational performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157

15.7

Screw press operational results summary . . . . . . . . . . . . . . . . . . . . . . . . 158

16.1

Comparison of stabilization processes . . . . . . . . . . . . . . . . . . . . . . . . . . . 164

16.2

Typical design and operating parameters for anaerobic digestion of wastewater solids in high-rate digesters . . . . . . . . . . . . . . 167

16.3

Components of the anaerobic digester system . . . . . . . . . . . . . . . . . . . . 169

16.4

Typical design and operating parameters for aerobic digestion of wastewater solids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170

16.5

Class B biosolids criteria that a conventional mesophilic aerobic digestion system typically is designed to meet . . . . . . . . . . . . . 172

16.6

Key advantages and disadvantages of composting systems . . . . . . . . 173

16.7

Materials balance for 1 dry ton of biosolids in aerated static-pile composting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174

16.8

Typical advanced alkaline stabilization design criteria . . . . . . . . . . . . . 175

17.1

Thermal processing technologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181

17.2

Design considerations for thermal processing . . . . . . . . . . . . . . . . . . . . 183

18.1

Odor and air emissions control technologies . . . . . . . . . . . . . . . . . . . . . 186

xvii

Preface This handbook is intended to complement several recognized wastewater treatment design references. It facilitates access to those design guides by providing concise information from them and enabling the reader to quickly locate additional information by following direct references. This handbook is organized similarly to the Design of Municipal Wastewater Treatment Plants (Water Environment Federation Manual of Practice No. 8; 5th Edition; 2009) publication so that cross references may be more easily found. This reference is written for students and design professionals familiar with wastewater treatment concepts, the design process, plant operations, and the regulatory basis of water pollution control. It is not intended to be a primer for either the inexperienced or the generalist but still a tool for them as well, allowing them to quickly identify where they can find more information for unfamiliar subjects. As such, the authors of this handbook are industry professionals who have used their experience as both students and design professionals to identify the most critical information to present in tables and figures. It is highly recommended that the reader does not rely solely on information, such as design criteria, identified by this handbook as it is not inclusive. A thorough understanding of the principles behind these summary chapters is necessary for the correct application and use of all information contained in this handbook. This publication was produced under the direction of Hannah T. Wilner, P.E., Chair. The principal authors of this publication are as follows: Chapter 1 Chapter 2 Chapter 3 Chapter 4 Chapter 5 Chapter 6 Chapter 7 Chapter 8 Chapter 9 Chapter 10

Hannah T. Wilner, P.E. Hannah T. Wilner, P.E. Hannah T. Wilner, P.E. Hannah T. Wilner, P.E. Sarah Hubbell Stephanie L. Spalding, P.E. Sarah Hubbell Eric Lynne Stephanie L. Spalding, P.E. Hannah T. Wilner, P.E. xix

xx

Preface Chapter 11 Chapter 12 Chapter 13 Chapter 14 Chapter 15 Chapter 16 Chapter 17 Chapter 18

Eric Lynne Sarah Hubbell Hannah T. Wilner, P.E. Eric Lynne Eric Lynne Stephanie L. Spalding, P.E. Hannah T. Wilner, P.E. Hannah T. Wilner, P.E.

Authors’ and reviewers’ efforts were supported by the following organizations: Black & Veatch Corporation, Kansas City, Missouri CDM Smith, Cambridge, Massachusetts CH2M HILL, Chicago, Illinois; Cincinnati and Columbus, Ohio; Englewood, Colorado; Overland Park, Kansas; Tampa, Florida; and Kitchener, Ontario, Canada Donohue and Associates, Sheboygan, Wisconsin Entex Technologies Inc., Chapel Hill, North Carolina GE Power & Water, Portland, Oregon GHD, Bowie, Maryland Hatch Mott MacDonald, Millburn, New Jersey JenTech Inc., Milwaukee, Wisconsin Johnson Controls, Inc., Milwaukee, Wisconsin Loyola Marymount University, Los Angeles, California Malcolm Pirnie, the Water Division of ARCADIS, Newport News, Virginia Metropolitan Sewer District of Greater Cincinnati, Cincinnati, Ohio Molzen Corbin, Albuquerque, New Mexico University of the Pacific, Stockton, California Veolia Water North America, Indianapolis, Indiana Wood, Patel & Assoc., Phoenix, Arizona