Understanding Water Quality Management - Technology and Applications

199 Pages·2004·5.571 MB·English

by  Eckenfelder, W. Wesley, Hansard, William Ney

Understanding
Water Quality Management
TECHNOLOGY AND APPLICATIONS
W. Wesley Eckenfelder
Brown & Caldwell, Inc.
William Ney Hansard
EMSI Solutions, Inc.
Understanding Water Quality Management
DEStechPublications, Inc.
1148 Elizabeth Avenue #2
Lancaster, Pennsylvania 17601 U.S.A.
Copyright © 2004 by DEStechPublications, Inc.
All Rights Reserved
Chapter photographs from USEPA National Water
Quality Inventory reports 1992–2000.
No part of this publication may be reproduced, stored in a
retrieval system, or transmitted, in any form or by any means,
electronic, mechanical, photocopying, recording, or otherwise,
without the prior written permission of the publisher.
Printed in the United States of America
10 9 8 7 6 5 4 3 2 1
Entry under main title:
Understanding Water Quality Management: Technology and Applications
ADEStechPublications book
Bibliography: p. 175
Includes index p. 177
ISBN: 1-932078-21-5
Foreword
LAWYERSwhopracticeintheenvironmentalfieldfaceadoublechallenge.
Notonlyarethelawsandrulesmind-bogglingintheircomplexity,butthe
underlyingsubjectmatterisdominatedbyconceptsfrombiology,chemistry,
statisticsandengineering.Whiletheenvironmentisaveryemotionalandeven
moralissueformostofus,tobeeffectiveinthearea,asonepractitionerputit,
you need a good engineer, not a poet.
Andyetmanylawyers,andothers,whoworkonenvironmentalissuesspent
more time in college studying poetry than science. To help bridge this gap, I
developed and now edit the Environmental Science Deskbook, published by
ThomsonWest.Thisbooktakesthebasicscientificandtechnicalconceptsthat
aremostpervasiveinenvironmentallawandregulationandexplainsthemin
plain English. (Seewww.westgroup.com).
When I was looking for prospective authors to write sections on surface
water quality and wastewater treatment, my first call went to my friend and
colleagueBillHansard.NotonlydidIknowandrespecthiswork,Ialsoknew
he could lead me to the acknowledged father of industrial wastewater
treatment, Wes Eckenfelder.
Thisbookisanexpandedversionofthosesections.Inadditiontoprovidinga
clear and comprehensive overview of water quality issues and the various
mechanismsforwastewatertreatment,thebookcontainsentirelynewsections
onlandtreatmentandwasteminimization—theultimatesolutiontowastewater
problems. It strikes a rare balance in being accessible to the non-technical
reader and informative to technical audiences.
I highly recommend this book.
JAMESW. CONRAD, JR.
Counsel
American Chemistry Council
xi
Preface
OVERthepastdecadetherehasbeenincreasedawarenessoftheimportance
of water quality. Many municipalities and industrial facilities have
upgraded or installed new technologies to meet the demand for clean water.
Advancesinwaterqualityscienceshowthatfurtherimprovementsareneeded
to ensure a plentiful water supply and to protect the natural environment.
Waterqualitymanagementisacomplexfieldthatrequiresparticipationby
manydiversedisciplines.Peoplefromallwalksoflife,includinggovernment
workers, attorneys, engineers, scientists, business managers, educators,
economists,politicians,environmentaladvocatesandthegeneralpublicneed
to know more about water quality management.
This volume has been prepared to provide an understanding of the basic
concepts and principles of managing surface water and industrial wastewater
quality.
Many universities currently offer introductory courses in environmental
management,primarilyforenvironmentalprofessionals.Thisbookrepresents
a primary text for courses in water pollution.
It is our hope that this volume will provide a greater understanding of the
challenges facing, and the solutions to, effective water pollution control.
xiii
Table of Contents
Foreword xi
Preface xiii
Acknowledgements xv
CHAPTER 1: SURFACE WATER QUALITY AND
AQUATIC ECOSYSTEMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
1.1 Progress in Water Quality 1
1.2 Leading Sources of Water Quality Impairment 2
1.3 Pollutant Loadings to Receiving Streams:
Total Maximum Daily Load (TMDL) Program 3
1.4 General Characteristics of Aquatic Ecosystems 5
CHAPTER 2: POLLUTANT CATEGORIES AND EFFECTS
ON SURFACE WATERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
2.1 Leading Causes of Water Quality Impairment 15
2.2 Pollution of Surface Waters 15
CHAPTER 3: CLASSIFICATION AND MEASUREMENT
OF POLLUTANTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
3.1 Conventional Pollutants 31
3.2 Other Pollutants 33
CHAPTER 4: WASTEWATER PRE-TREATMENT
TECHNOLOGIES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
4.1 Wastewater Treatment Unit Operations 41
4.2 Screening and Grit Removal 43
4.3 Equalization 44
vii
viii Table of Contents
4.4 Primary Clarification 47
4.5 Neutralization 48
4.6 Oil Removal 49
4.7 Flotation 54
CHAPTER 5: BIOLOGICAL TREATMENT
TECHNOLOGIES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57
5.1 Activated Sludge Treatment 60
5.2 Other Suspended Growth Biological
Treatment Systems 70
5.3 Attached Growth Systems 75
5.4 Anaerobic Biological Treatment Systems 76
CHAPTER 6: PHYSICAL/CHEMICAL TREATMENT
TECHNOLOGIES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .87
6.1 Activated Carbon Adsorption 87
6.2 Ion Exchange Systems 92
6.3 Stripping 95
6.4 Coagulation and Flocculation 99
6.5 Heavy Metals Removal 104
6.6 Chemical Oxidation and Reduction 106
6.7 Hydrothermal Oxidation 108
CHAPTER 7: PHYSICAL SEPARATION
TECHNOLOGIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .111
7.1 Filtration 111
7.2 Membrane Technologies 113
CHAPTER 8: DISINFECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . .121
CHAPTER 9: NUTRIENT REMOVAL. . . . . . . . . . . . . . . . . . . . . . . .125
9.1 Phosphorus Removal 125
9.2 Nitrogen Removal 128
CHAPTER 10: SLUDGE HANDLING AND DISPOSAL . . . . . . . . .133
10.1 Types of Sludges 135
10.2 Sludge Thickening 135
10.3 Sludge Dewatering 137
10.4 Sludge Disposal 141
Table of Contents ix
CHAPTER 11: LAND TREATMENT. . . . . . . . . . . . . . . . . . . . . . . . .147
11.1 Spray Irrigation and Overland Flow Systems 147
11.2 Wastewater Characteristics and Design Considerations 149
CHAPTER 12: WASTE MINIMIZATION AND
WATER REUSE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .153
12.1 Waste Minimization Techniques 153
12.2 Waste Minimization Assessment 154
12.3 Pollution Reduction Methods 154
12.4 Case Histories and Examples 157
12.5 Recycle/Reuse and Treatment Cost Considerations 161
CHAPTER 13: ECONOMICS OF WASTEWATER
TREATMENT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .165
13.1 Capital Cost Estimates 165
13.2 Operation and Maintenance Cost Estimates 168
13.3 Present Value Cost Analysis 168
References 173
Bibliography 175
Index 177
About the Authors 192
CHAPTER 1
Surface Water Quality and
Aquatic Ecosystems
1.1 PROGRESS IN WATER QUALITY
INthe1970s,muchofLakeEriewaslittlemorethanaeutrophiedcesspool.
Agricultural runoff and organic and nutrient loadings from untreated or
partiallytreatedsewageandindustrialwastecauseddissolvedoxygenlevelsin
thelaketodrop,introducedtoxiceffects,andstimulatedanexplosioninalgal
growth, leading to eutrophication and strangulation of the lake’s aquatic
ecosystems. In the early 1970s, anglers could only catch “trash” fish such as
carp and eel in many sections of the lake, and much of the lake was posted
against swimming due to the presence of pathogens and toxic chemicals.
Around the same time, the Cuyahoga River in Ohio caught fire due to
pollution from chemical plants and refineries. The Kanawha River at
Charleston,WestVirginiawasessentiallyanopenchemicalsewerintheearly
1970s. Severely mutated fish and other aquatic organisms were frequently
found.Polychlorinatedbiphenyls(PCBs)werefoundinpolarbearfleshinthe
Arctic Circle and in mothers’ milk in the United States. The pesticide DDT
weakenedeggshellsinthebrownpelican,baldeagle,andotherbirdsfeedingat
the top of their food chain, and threatened them with extinction.
Loss of habitat and the effects of pollution have significantly endangered
America’saquaticwildlife.IntheIllinoisRiver,forexample,approximately66
percent of the indigenous fish species have vanished because of water
pollution. In Muscle Shoals, Alabama, 30 of 63 mussel species disappeared
aftertheconstructionofamajordam.IntheChesapeakeBay,fishandshellfish
harvestshavebeenoffdramaticallysincethe1960s—a96percentdeclinefor
hickory shad catches alone.
As governmental regulation has clamped down on point sources of water
pollution, significant progress towards recovery has been made. Yet, much
remains to be done.
Everytwoyears,EPAsubmitsitsNationalWaterQualityInventoryreportto
1
2 SURFACE WATER QUALITY AND AQUATIC ECOSYSTEMS
TABLE 1.1. Summary of Quality of Assessed Rivers,
Lakes and Estuaries [1].
Good but
Amount Good Threatened Polluted
Assessed (% of (% of (% of
Total Size (% of Total) Assessed) Assessed) Assessed)
Rivers and 3,692,830 699,946 367,129 59.504 269,258
Streams (miles) (19%) (53%) (8%) (39%)
Lakes, Ponds and 40,603,893 17,339,080 8,026,988 1,348,903 7,702,370
Reservoirs (acres) (43%) (47%) (8%) (45%)
Estuaries (square 87,369 31,072 13,850 1,023 15,676
miles) (36%) (45%) (<4%) (51%)
Congress.Thisreportsummarizeswaterqualitydatacollectedbyall50states,
Interstate Water Commissions, American Indian Tribes, and the District of
Columbia. By 2000, government agencies had surveyed approximately
700,000milesofriversandstreams(approximately19percentofthenation’s
total);17,339,080acresoflakes(43%ofthetotal);and31,072squaremilesof
estuaries (36% of the total).
Table 1.1 summarizes some of the results of EPA’s 2000 National Water
Quality Inventory [1], and indicates whether the surface waters surveyed
supporttheirintendeduses.Ascanbeseenfromthistable,only53percentof
the nation’s rivers and streams, 47 percent of lakes, and only 45 percent of
estuariessurveyedareconsideredtobeofgoodquality,supportingmostorall
of the water quality needs and objectives.
1.2 LEADING SOURCES OF WATER QUALITY IMPAIRMENT
Table 1.2, reproduced from the 2000 National Water Quality Inventory,
summarizestheleadingcausesandsourcesofwaterqualityimpairmentinthe
United States today.
The public has the general impression that industrial plants are the major
cause of water pollution. Thus, many people are surprised to find that the
current leading causes of surface water pollution are from agriculture,
municipalwastewaterpointsources,hydrologicmodification(channelization,
flowregulationanddredging),andurbanrunoff/stormsewers.Thisisbecause
industrial wastewater point sources of pollution are now treated prior to
discharge,dueprimarilytoenforcementoftheCleanWaterAct.Priortothat
act, this was not the case.
Laterchaptersofthisbookdescribethevarioustechnologiesthathavebeen
drivenbytheCleanWaterAct’smassiveregulatoryregimeforpointsources.
This regime will continue to impose more stringent limits as the technology
Pollutant Loadings to Receiving Streams 3
TABLE 1.2. Leading Causes and Sources* of Impairment in Assessed
Rivers, Lakes and Estuaries [1].
Lakes, Ponds, and
Rivers and Streams Reservoirs Estuaries
Causes Pathogens (Bacteria) Nutrients Metals (Primarily
mercury)
Siltation Metals (Primarily mercury) Pesticides
(Sedimentation)
Habitat Alterations Siltation (Sedimentation) Oxygen-Depleting
Substances
Sources Agriculture Agriculture Municipal Point
Hydrologic Modification Hydrologic Modification Sources
Urban Runoff/Storm
Habitat Modification Urban Runoff/Storm Sewers
Sewers Industrial Discharges
*Excluding unknown, natural, and “other” sources.
continuestoadvance.Buttheresultswillyielddecliningreturns,particularly
compared to the significant problems currently caused by agricultural and
urbannon-pointsourcerunoff.Manyofthetechniquesthatwillberequiredto
remedythesechallengingproblemsaremuchsimpler,technicallyspeaking,but
far more challenging politically to impose. Nonetheless, this difficult work
mustbecontinuedtobringallofthenations’waterwaystothedesiredlevelof
quality.
1.3 POLLUTANT LOADINGS TO RECEIVING STREAMS:
TOTAL MAXIMUM DAILY LOAD (TMDL) PROGRAM
Section303(d)oftheCleanWaterAct(CWA)requireseachstatetoidentify
thesectionsoflakes,riversandstreamsthatareimpaired;i.e.,theydonotmeet
atleastonewaterqualitystandardestablishedforthem.(Itdoesnotnecessarily
meanthatthepollutionissobadthatitrepresentsathreattohumanhealthora
serious threat to the environment.) The states are then required to establish a
totalmaximumdailyload(TMDL)foreachpollutantaffectingeachimpaired
aquatic ecosystem.
ATMDListheamountofapollutantthatawaterbodycanreceiveinaday
andstillmeetwaterqualitystandards.TheTMDLhasbeentermeda“pollution
budget.” The TMDL is a calculated amount that must account for seasonal
variability in water quality, and include a margin of safety to ensure that the
waterbodycanmeetthewaterqualitystandardsthestatehasdesignated.By
establishing TMDLs, it is believed, states and communities can identify the
causesandsourcesofthespecificpollutantsimpairingeachwatersystem,and
develop plans to stop the pollution.