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New edition covers the latest practices, regulations, andalternative disinfectants Since the publication of the Fourth Edition of White'sHandbook of Chlorination and Alternative Disinfectants morethan ten years ago, the water industry has made substantialadvances in their understanding and application of chlorine,hypochlorite, and alternative disinfectants for water andwastewater treatment. This Fifth Edition, with its extensiveupdates and revisions, reflects the current state of the science aswell as the latest practices. Balancing theory with practice, the Fifth Edition coverssuch important topics as: * Advances in the use of UV and ozone as disinfectants * Alternative disinfectants such as chlorine dioxide, iodine, andbromine-related products * Advanced oxidation processes for drinking water and wastewatertreatment * New developments and information for the production and handlingof chlorine * Latest regulations governing the use of differentdisinfectants For each disinfectant, the book explains its chemistry,effectiveness, dosing, equipment, and system design requirements.Moreover, the advantages and disadvantages of each disinfectant areclearly set forth. References at the end of each chapter guidereaders to the primary literature for further investigation. Authored and reviewed by leading experts in the field of waterand wastewater treatment, this Fifth Edition remains anideal reference for utilities, regulators, engineers, and plantoperators who need current information on the disinfection ofpotable water, wastewater, industrial water, and swimmingpools.

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CONTENTS

Preface

Authors

List of Contributors and Reviewers

List of Abbreviations

Acknowledgments

1 Chlorine: History, Manufacture, Properties, Hazards, and Uses

Historical Background

Manufacture of Chlorine

Electrolytic Cell Development

Other Chlorine Manufacturing Processes

Impurities in the Manufacture of Chlorine

Physical and Chemical Properties of Chlorine

Hazards from Chlorine Vapor and Liquid

Chlorine Leaks

Calculating Chlorine Leak Rates

Summary

USEPA Risk Management Programs (RMPs)

Chlorine Transport Accidents

Notable Consumer Accidents

Production and Uses of Chlorine

References

2 Chemistry of Aqueous Chlorine

Dissolution and Hydrolysis of Chlorine

Dissociation of Hypochlorous Acid

Chlorine Speciation in Concentrated Solutions

Hypochlorite Solutions

Oxidation States of Chlorine

Free, Combined, and Available Chlorine

Chlorine and Nitrogenous Compounds

The Chemistry of Chlorine in Seawater

Oxidation–Reduction Reactions of Chlorine Compounds

ORP Measurements

Reactions of Chlorine with Selected Constituents

Chlorine Demand

Germicidal Significance of Chlorine Residuals

References

3 Determination of Chlorine Residuals in Water and Wastewater Treatment

Historical Background

General Considerations

Amperometric Titration

DPD Method

FACTS (Syringaldazine) Method

Iodometric Method I

Iodometric Method II (Wastewater)

Iodometric Electrode Method

Leuco Crystal Violet (LCV) Method

Methyl Orange (MO) Method

Orthotolidine Method

References

4 Chlorination of Potable Water

Microbes in Water Supplies

Waterborne Diseases

Chlorine as a Disinfectant

Disinfection Requirements under (Provisions of the) Safe Drinking Water Act (SDWA)

Disinfection of Drinking Water with Clorine

Disinfection with Chloramines

Distribution System

Disinfection of New Infrastructure

Other Uses of Chlorine in Water Treatment

Chlorination in the United Kingdom

Chlorination in Germany

Treatment Strategies

Acknowledgments

References

5 Chlorination of Wastewater

Introduction

Odor Control

Chlorine and Biological Treatment

Other Uses of Chlorine in Wastewater Treatment

Industrial Waste Treatment Applications Using Chlorine

References

6 Disinfection of Wastewater

Introduction

Viruses

Methods of Wastewater Disinfection

Chemistry of Wastewater Disinfection by Chlorine

Formation of DBPS

Other Disinfection Considerations

Wastewater Reuse

References

7 Chlorine Contact Basin Design

Introduction

Design Elements

References

8 Chlorine Feed Systems

Cylinders

Ton Containers

Tank Trucks/Tank Cars

Storage Tanks

Liquid Chlorine Feed

Appurtenances

Chlorine Feeders and Eductors

Reference

9 Hypochlorination — Sodium Hypochlorite

Background and History of Hypochlorites

Sodium Hypochlorite

Degradation

Impact on Treatment Process

Tank Selection

Transfer and Feed Equipment

Sodium Hypochlorite Piping

Sodium Hypochlorite Valves

Sodium Hypochlorite Facility Layouts

Calcium Hypochlorite

Lithium Hypochlorite

References

10 On-Site Sodium Hypochlorite Generation System

Historical Background1

Raw Material Quality

On-Site Generation of Sodium Hypochlorite

System Components

On-Site Sodium Hypochlorite Generation System Design

System Manufacturers

References

11 Dechlorination

Introduction

Sulfur Dioxide

Sulfite Compounds

Other Dechlorination Chemicals

Dechlorination Facility Design

References

12 Process Controls for Chlorination and Dechlorination

Introduction

Background

Online Analytical Measurements

Online Analyzers for Chlorination

Online Process Control Overview

Chlorination Process Control

Dechlorination

Online Analyzers for Dechlorination

Blending Chemistry with Process Control

Control System O&M

Record Keeping and Regulatory Issues

References

13 Operation and Maintenance

General

Chlorine Gas Systems

Sodium Hypochlorite Systems

Dechlorination Gas Systems

Dechlorination Liquid Systems

Operator Training and Safety

Storage Systems

Regulatory Requirements

14 Chlorine Dioxide

Introduction

Chemical and Biologic Properties

Equipment and Generation

Use in Drinking Water and Wastewater Disinfection

Other Disinfection Applications

Other Uses for Chlorine Dioxide in Water Treatment

Analytic Methods for Chlorine Dioxide and its Oxychlorine By-Products

Health and Safety

Regulatory Issues

Summary

Acknowledgments

References

15 Ozone

Introduction

History and Application

Chemical Properties

Inorganic Compound Treatment

Organic Compounds

Disinfection

Ozone DBPS

Use in Water and Wastewater Treatment

Equipment and Generation

Process Calculations

Quench Chemicals

Analytical Methods

Health and Safety

Regulatory Issues

References

16 Bromine, Bromine Chloride, BCDMH, and Iodine

Bromine (Br2)

Use of Bromine in Water Treatment Processes

Bromides: On-Site Generation of Br2

Bromine Chloride (BrCl)

BCDMH

Iodine (I2)

Summary

References

17 Ultraviolet Light

Introduction

Chemical and Biological Properties

Guidelines

UV Equipment

Water Quality Issues

UV System Sizing Tools

Operation and Maintenance Activities

Troubleshooting Strategies

Health and Safety for Water And Wastewater UV Systems

References

18 Advanced Oxidation Processes

Introduction

Chemistry of AOPs

Uses in Drinking Water and Wastewater Treatment

Factors Affecting System Performance

Regulations

Equipment and Generation

References

Appendix

Index

Copyright © 2010 by John Wiley & Sons, Inc. All rights reserved.

Published by John Wiley & Sons, Inc., Hoboken, New JerseyPublished simultaneously in Canada

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Library of Congress Cataloging-in-Publication Data:

White’s handbook of chlorination and alternative disinfectants. – 5th ed./Black & Veatch Corporation.p. cm.Rev. ed. of: Handbook of chlorination and alternative disinfectants/Geo. Clifford White. 4th ed. 1999.Includes bibliographical references and index.ISBN 978-0-470-18098-3 (cloth)1. Water–Purification–Chlorination. 2. Sewage–Purification–Chlorination.3. Water–Purification–Disinfection. I. White, George Clifford. Handbook of chlorination and alternative disinfectants. II. Black & Veatch. III. Title. IV. Title: Handbook of chlorination and alternative disinfectants.TD462.W47 2010628.1'662–dc222009022484

This Fifth Edition of the Handbook of Chlorination and Alternative Disinfectants is dedicated to George Clifford White for his lifetime commitment to the disinfection industry.

PREFACE

Over the years, the science and practice of disinfection has provided innumerable health benefits, although the general public is unaware of many of them. With the recognition of infectious organisms such as Cryptosporidium in our raw water supplies, along with the detrimental chronic health effects associated with disinfection by-products, it is critical to balance the extent of their inactivation with the concentrations of disinfection by-products. Many water and wastewater utilities are implementing the use of multiple disinfectants in order to optimize the results while minimizing unwanted side effects.

The four previous editions of this handbook have proven to be a valuable resource to countless utilities, regulators, engineers, and operators for information on disinfection of potable water, wastewater, industrial water, and swimming pools. George Clifford White’s efforts in compiling these editions are invaluable; and much of the information he has gathered is included in this current edition; some of it is retained solely to provide a historical perspective.

Since the publication of the fourth edition, the water industry has gained a substantial amount of experience with chlorine, hypochlorite, and alternative disinfectants through research, development, and regulation. Consequently, this handbook has been extensively revised and updated to reflect the most current understanding and practices. The reader will find substantial and important information not only on chlorination but also on alternative disinfectants such as ozone, chlorine dioxide, bromine-related products, and ultraviolet light. In addition, the global focus on reuse to address the issue of water scarcity has elevated the use of advanced oxidation practices, and that chapter has therefore been updated to reflect today’s environment.

Each chapter has been prepared by experts and reviewed by their peers in an effort to impart accurate, complete, and current knowledge on the subject being discussed. Black & Veatch considers it a privilege to present this updated resource on chlorination and alternative disinfectants for the water and wastewater industries.

It is our intention that this handbook continue to be the disinfection reference of choice for designers, operator, engineers, students, and regulators.

CINDY WALLIS- LAGEBlack & VeatchEditor

AUTHORS

Chapter 1 Chlorine: History, Manufacture, Properties, Hazards, and Uses

Leland L. Harms, PhD, P.E., Black & Veatch (Retired)

Walter J. O’Brien, ScD, P.E., Black & Veatch (Retired)

Chapter 2 Chemistry of Aqueous Chlorine

Stephen J. Randtke, PhD, P.E., University of Kansas

Chapter 3 Determination of Chlorine Residuals in Water and Wastewater Treatment

Stephen J. Randtke, PhD, P.E., University of Kansas

Chapter 4 Chlorination of Potable Water

Holly Shorney-Darby, PhD, P.E., Black & Veatch

Leland L. Harms, PhD, P.E., Black & Veatch (Retired)

Chapter 5 Chlorination of Wastewater

Edmund A. Kobylinski, P.E., Black & Veatch

Alok Bhandari, PhD, P.E., Iowa State University

Chapter 6 Disinfection of Wastewater

Edmund A. Kobylinski, P.E., Black & Veatch

Alok Bhandari, PhD, P.E., Iowa State University

Chapter 7 Chlorine Contact Basin Design

Neil S. Massart, P.E., Black & Veatch

Trevor H. Cooke, P.E., Black & Veatch

Chapter 8 Chlorine Feed Systems

Edward D. Vogt, P.E., Black & Veatch

Chapter 9 Hypochlorination-Sodium Hypochlorite

Kenneth A. Lewis, P.E., Black & Veatch

Chapter 10 On-Site Sodium Hypochlorite Generation Systems

Erin R. Briggeman, P.E., Black & Veatch

Chapter 11 Dechlorination

Neil S. Massart, P.E., Black & Veatch

Ladan Holakoo, PhD, P.E., P.Eng., Black & Veatch

Chapter 12 Process Controls for Chlorination and Dechlorination

Edmund A. Kobylinski, P.E., Black & Veatch

Timothy A. Holmes, P.E., Black & Veatch

Chapter 13 Operations & Maintenance

Neil S. Massart, P.E., Black & Veatch

Chapter 14 Chlorine Dioxide

Robert C. Hoehn, PhD, Professor Emeritus, Virginia Polytechnic Institute & State University

Holly Shorney-Darby, PhD, P.E., Black & Veatch

Jeff Neemann, P.E., Black & Veatch

Chapter 15 Ozone

Nick L. Burns, P.E., Black & Veatch

Chapter 16 Bromine, Bromine Chloride, BCDMH, and Iodine

Gary L. Hunter, P.E., Black & Veatch

Hua Jiang, PhD, P.E., Black & Veatch

Chapter 17 Ultraviolet Light

Gary L. Hunter, P.E., Black & Veatch

Bryan R. Townsend, Black & Veatch

Chapter 18 Advanced Oxidation Processes

Rick Bond, P.E., Black & Veatch

LIST OF CONTRIBUTORS AND REVIEWERS

MARC-OLIVIER BUFFLE, PhD, Sustainable Asset Management AG, Chapter 18

MICHAEL F. COUGHLIN, PhD, Johnson Diversey, Chapter 14

DOUG ELDER, P.E., Black & Veatch, Chapter 7

WILLIAM FEHRMAN, Severn Trent Services, Chapter 8

DAVID H. FRIESS, Black & Veatch, Chapter 13

ALBERTO GARIBI, Siemens Water Tech., Chapter 10

JULIA V. GASS, P.E., Black & Veatch, Chapter 15

DON GATES, PhD, Consultant, Chap ter 14

DAN C. GAY, P.E., Black & Veatch, Chapter 9

ALI GITI, Severn Trent Services, Chapter 10

GILBERT GORDON, PhD, Professor Emeritus, Miami University, Ohio, Chapters 2 and 3

LELAND L. HARMS, PhD, P.E., Black & Veatch (Retired), Chapter 2

ROBERT A. HULSEY, P.E., Black & Veatch, Chapter 15

SAMUEL JEYANAYAGAM, PhD, P.E., DEE, Malcolm Pirnie, Chapters 5, 6 and 17

KARL G. LINDEN, PhD, University of Colorado, Chapter 17

DAN W. MEYER, P.E., Black & Veatch, Chapter 1

ROGER D. MILLER, Layne Christensen Company, Chapter 4

JEFF NEEMANN, P.E., Black & Veatch, Chapter 15

GARY W. NEUN, Black & Veatch, Chapter 13

GUSTAVO FM QUEIROZ, P.E., Black & Veatch, Chapter 10

KERWIN L. RAKNESS, Process Applications, Inc., Chapter 15

STEPHEN J. RANDTKE, PhD, P.E., University of Kansas, Chapter 4

DON D. RATNAYAKA, CEng, Black & Veatch, Chapters 4 and 14

ANDREW R. SHAW, P.E., Black & Veatch, Chapters 3 and 12

HOLLY SHORNEY-DARBY, PhD, P.E., Black & Veatch, Chapter 2

EDWARD D. VOGT, P.E., Black & Veatch, Chapters 9, 10 and 11

ELLIOTT WHITBY, PhD, Calgon Carbon Corp., Chapter 17

TIMOTHY J. WHITE, P.E., Black & Veatch, Chapter 4

LIST OF ABBREVIATIONS

ACalternating currentACCAmerican Chemical Council; automatic control centerACGIHAmerican Conference of Governmental Industrial HygienistsAIHAAmerican Industrial Hygiene AssociationANSIAmerican National Standards InstituteAOBammonia oxidizing bacteriaAOCassimilable organic carbonAOPadvanced oxidation processAOXPadvanced oxidation processASanalog subsystemATEXexplosive atmosphere directive (UK)AWTadvanced wastewater treatmentAWWAAmerican Water Works AssociationAwwaRFAmerican Water Works Association Research FoundationBACbiological activated carbonBDOCbiodegradable dissolved organic carbonBFbaffling factorBOCABuilding Officials and Code Administrators, InternationalBODbiochemical oxygen demandB-PbreakpointCAcellulose acetateCAAchloracetic acidCACcombined available control systemCANUTECCanadian Transport Emergency CentreCCCScentral computer control systemCFDcomputational fluid dynamicsCHEMTRECChemical Transportation Emergency CenterCIChlorine InstituteCODchemical oxygen demandCOMAHcontrol of major accident hazard (U.K.)CPchloropicrinCPRVchlorine pressure-reducing valveCRCcombined residual chlorineCScontrol systemCSBChemical Safety and Hazard Investigation Board (U.S.)CSOcombined sewer overflowCTchlorine residual x contact timeCTCcentral terminal controlD/DBPRDisinfectants/Disinfection Byproducts RuleDBPdisinfection byproductDCdirect currentDEdiatomaceous earthDIWdeionized waterDNAdeoxyribonucleic acidDOdissolved oxygenDOCdissolved organic carbonDOTDepartment of TransportationDPDdiethyl-p-phenylenediamineDPHDepartment of Public HealthDPPdifferential pulse polarographyDSAdimensionally stable anodesDXAAsdihaloacetic acidsEBCTempty bed contact timeEDelectrodialysisEDCendocrine disrupting compoundEDPethyl dibromideEESemergency service specialistEFVexcess flow valveEPAEnvironmental Protection Agency (also USEPA)EPDMethylene propylene diene monomerEPSextracellular polymer substancesERPGEmergency Response Planning GuidelinesFACfree available chlorineFACTSfree available chlorine test – syringaldazineFASferrous ammonium sulfateFCfecal coliformFIAflow injection analysisFPAflavor profile analysisFRCfree residual chlorineFRPfiberglass-reinforced plasticGACgranular activated carbonGOXgaseous oxygenGUDIgroundwater under the direct influenceGWRGroundwater RuleHAAhaloacetic acidHAA5five regulated HAAsHANhalo acetonitrileHFFhollow fine fiberHPCheterotrophic plate countHRThydraulic retention timeHSEHealth and Safety Executive (U.K.)ICion chromatographyICRInformation Collection RuleIDLHimmediate danger to life and healthIESWTRInterim Enhanced Surface Water Treatment RuleIFCIInternational Fire Code InstituteIXion exchangeLCRLead and Copper RuleLOXliquid oxygenLSLlower sensitivity limitLT1ESWTRLong-term 1 Enhanced Surface Water Treatment RuleLT2ESWTRLong term 2 Enhanced Surface Water Treatment RuleMCAManufacturing Chemists AssociationMCLmaximum contaminant levelMCLGmaximum contaminant level goalMDLmethod detection limitMFmicrofiltrationMFImodified fouling indexMIB2-methylisoborneolMLVSSmixed liquor volatile suspended solidsMPNmost probable numberMRDLGmaximum residual disinfectant level goalMSDSmaterial safety data sheetsMWCminimum water columnMWDmaximum water depth; Metropolitan Water District; minimum water depthNDMAN-nitrosodimethylamineNFnanofiltrationNFPANational Fire Protection AssociationNMWnominal molecular weightNOBnitrite-oxidizing bacteriaNOMnatural organic matterNPDESNational Pollutant Discharge Elimination SystemNSFNational Sanitation FoundationNTSBNational Transportation Safety BoardORPoxidation-reduction potentialOSHAOccupational Safety and Health AdministrationOTorthotolidineOTAorthotolidine-arsenitePACpowdered activated carbonPAOphenylarsine oxidePCprogrammable controllerPCBpolychlorinated biphenylPCSprocess control softwarePDWFpeak dry weather flowPFUplaque-forming unitPICSprocess instrument control systemPLCprogrammable logic controllerPPCPpharmaceutical and personal care productPSApressure swing adsorptionPSMprocess safety managementPSSpoint summation sourcePSUpower supply unitPTFEpolytetrafluoroethylenePVCpolyvinyl chlorideRAArunning annual averageRASreturn activated sludgeRCPreinforced concrete pipeRMPrisk management programRMPPrisk management protection planROreverse osmosisRSIRailway Supply InstituteRTKright-to-knowRTUremote terminal unitSCFshort circuiting factorSDHsuccinic dehydrogenaseSDIsilt density indexSDWASafe Drinking Water ActSETIQSistema de Emergencies en Transporte para la Industria QuimicaSFPCStandard Fire Prevention AssociationSHMPsodium hexametaphosphateSLSsodium lauryl sulfateSMCLsecondary maximum contaminant levelsSOCsynthetic organic compoundSPCstandard plate countSSsuspended solidsSTELshort-term exposure limitSWspiral woundSWTRSurface Water Treatment RuleTCtotal coliformTCAtrichloroacetic acidTCEtrichloroethyleneTCEPtris (2-chloroetlyl) phosphateTDDtriple distilled deionizedTDHtotal dehydrogenase; total dynamic headTDStotal dissolved solidsTFCthin-film compositeTHMtrihalomethanesTHMFPtrihalomethane formation potentialTLVthreshold limit valueTOCtotal organic carbonTONthreshold odor numberTOXtotal organic halidesTRANSSCAERTransportation Community Awareness and Emergency ResponseTRCtotal residual chlorineTSStotal suspended solidsTTCEtetrachloroethyleneTTHMtotal trihalomethaneTWAtime weighted averageUBCUniform Building CodeUFultrafiltrationUFCUniform Fire CodeUPUnion PacificUSEPAUnited States Environmental Protection Agency (also EPA)USGSUnited States Geological ServiceUVultravioletUVAultraviolet absorbance at 254 nmVOCvolatile organic carbon/compoundVSAvacuum swing adsorptionWEFWater Environment FederationWPCFWater Pollution Control FederationWTPwater treatment plantWWTPwastewater treatment plant

ACKNOWLEDGMENTS

We give special thanks to Alan Ingham and Dan Wright for assistance with graphic arts. We are also grateful for the assistance and compilation efforts of Rhonda Hoyt.

1

Chlorine: History, Manufacture, Properties, Hazards, and Uses

HISTORICAL BACKGROUND

Elemental Chlorine

Chlorine is an element of the halogen family, but it is never found uncombined in nature. It is estimated to account for 0.15% of the earth’s crust in the form of soluble chlorides, such as common salt (NaCl), carnallite (KMgCl3 · 6H2O), and sylvite (KCl). In nature, it exists only as the negative chloride ion with a valence of −1. Because its properties in the gaseous, liquid, and aqueous states differ widely, each phase will be discussed separately.

Chlorine Gas

Medieval Arab chemist Geber must have known this element (ca. 720–810). Chlorine was discovered, in its gaseous state, in 1774 by Karl W. Scheele, a Swedish chemist, when he heated manganese dioxide with hydrochloric acid.1

(1.1)

Scheele called the gas he discovered “dephlogisticated muriatic acid” on the theory that manganese had displaced “phlogiston” (as hydrogen was then called) from the muriatic acid (HCl). Scheele also observed that the gas was soluble in water, that it had a permanent bleaching effect on paper, vegetables, and flowers, and that it acted on metals and oxides of metals.

During the decade following Scheele’s discovery, Lavoisier attacked and, after a memorable struggle, completely upset the phlogiston theory of Scheele. Lavoisier was of the opinion that all acids contained oxygen. Berthollet found that a solution of Scheele’s gas in water, when exposed to sunlight, gives off oxygen and leaves behind muriatic acid. Considering this residue proof of Lavoisier’s theory, Berthollet called it oxygenated muriatic acid.2 However, Humphry Davy was unable to decompose Scheele’s gas. On July 12, 1810, before the Royal Society of London, he declared the gas to be an element, in which muriatic acid is combined with hydrogen. Therefore, Lavoisier’s theory that all acids contain oxygen had to be discarded. Davy proposed to name the gas “chlorine” from the Greek chloros, variously translated “green,” “greenish yellow,” or “yellowish green,” in allusion to its color.

Pelletier in 1785 and Karsten in 1786 succeeded in producing yellow crystals of chlorine hydrate by cooling Scheele’s gas in the presence of moisture. From this, they inferred that it was not an element. In 1810, Davy proved that the crystals could not be formed by cooling the gas even to −40 °F in the absence of moisture. It is now known that these crystals are in fact chlorine hydrate (Cl2 · 8H2O) and will form under standard conditions with chlorine gas in the presence of moisture and at a temperature of at least 49.3 °F.

Chlorine Liquid

In 1805, Thomas Northmore noted that Scheele’s gas became a yellowish amber liquid under pressure, and upon release of the pressure it volatilized rapidly and violently into a green gas. He further noted that it had a pungent odor and caused severe damage to machinery.

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