1、Science and TechnologyAWWA unites the entire water community by developing and distributing authoritative scientific and technologicalknowledge. Through its members, AWWA develops industry standards for products and processes that advance publichealth and safety. AWWA also provides quality improveme
2、nt programs for water and wastewater utilities.Water Chlorination/Chloramination Practices and PrinciplesAWWA MANUAL M20Second EditionMANUAL OF WATER SUPPLY PRACTICESM20, Second EditionWater Chlorination/Chloramination Practices and PrinciplesCopyright 2006 American Water Works AssociationAll rights
3、 reserved. No part of this publication may be reproduced or transmitted in any form or by anymeans, electronic or mechanical, including photocopy, recording, or any information or retrieval system,except in the form of brief excerpts or quotations for review purposes, without the written permission
4、ofthe publisher.DisclaimerThe authors, contributors, editors, and publisher do not assume responsibility for the validity of thecontents or any consequences of their use. In no event will AWWA be liable for direct, indirect, special,incidental, or consequential damages arising out of the use of info
5、rmation presented in this book. Inparticular, AWWA will not be responsible for any costs, including, but not limited to, those incurred asa result of lost revenue. In no event shall AWWAs liability exceed the amount paid for the purchase ofthis book.Project Manager: Mary Kay KozyraProduction Editor:
6、 Carol StearnsManuals Coordinator: Beth BehnerLibrary of Congress Cataloging-in-Publication DataWater Chlorination/chloramination practices and principlesp. cm. - (AWWA manual ; M20)Rev. ed. of: Water chlorination principles and practices. 1973.ISBN 1-58321-408-91. Water-Purification-Chlorination. 2
7、. Water-Purification-Chloramination. I.American Water Works Association. II. Water chlorination principles and practices. III. SeriesTD491.A49 no. M20 2006TD462628.1 s-dc22628.1662 2005057037Printed in the United States of AmericaAmerican Water Works Association6666 West Quincy AvenueDenver, CO 8023
8、5ISBN 1-58321-408-9 Printed on recycled paperContentsiiiFigures, vTables, ixForeword, xiAcknowledgments, xiiiChapter 1History of Chlorination and Chloramination. 1Origin of Water Disinfection, 1Rationale of Water Disinfection, 2Evolution of Chlorination Materials, 3Evolution of Chlorination Control
9、Practices, 3Discovery of Trihalomethanes, 4Historical Development of Chloramine, 4Evolution of Chloramination Materials, 5Evolution of Chloramination Control Practices, 5Disinfection Regulations in the United States, 6International Disinfection Regulations, 6The Future, 6References, 7Additional Sour
10、ces of Information, 7Chapter 2Properties of Chlorination Chemicals 9Chlorine Gas, 9Sodium Hypochlorite, 12Ammonia Gas, 15Ammonia Solutions, 16References, 17Additional Sources of Information, 17Chapter 3 Chlorination Water Chemistry and Disinfection Mechanisms.19Chlorination Chemistry, 19Disinfection
11、 Mechanism, 25Disinfection Methods, 27References, 30Additional Sources of Information, 30Chapter 4 Chlorine and Ammonia: Handling, Storage, Feed Equipment, and Systems 31Gas Chlorination Facilities, 31Handling and Storing Chlorine Gas, 32Feeding Chlorine Gas, 36Liquid Hypochlorite Facilities, 50Ammo
12、nia Gas (Anhydrous Ammonia) Facilities, 56Aqua Ammonia Facilities, 58Common Facilities for Liquid Chemicals, 60Ancillary Equipment, 61References, 69ivChapter 5Chlorine and Ammonia Safety 71Safety-Related Chemical and Physical PropertiesChlorine, 71Medical Aspects and First AidChlorine, 84Sodium Hypo
13、chlorite Safety Considerations, 86Ammonia Gas Safety Considerations, 90Aqua Ammonia (Ammonium Hydroxide) Safety Considerations, 93Chlorine and Ammonia Facility Requirements, 94References, 96Additonal Sources of Information, 96Chapter 6Chlorine/Chloramine Disinfection Strategies 97Microbial/Disinfect
14、ion By-products Dilemma, 97Optimizing the Chlorination/Chloramination Disinfection Process, 104Distribution System Chlorination (Booster or Secondary Chlorination), 112Treatment Plant Chlorination/Chloramination Strategies, 116References, 120Additional Sources of Information, 121Appendix ADechlorina
15、tion. 123Dechlorination Practices, 124Chemical Feed Techniques, 131References, 136Appendix B CT Values for Inactivation of Giardia and Viruses by Free Chlorine and Other Disinfectants. 137Appendix CChlorine Residual Test Methods 143Purpose of Test, 143List of Simplified Methods, 144Simplified Proced
16、ures, 144References, 154Appendix DDisinfection (Chlorination) of Facilities. 155List of AWWA Manuals, 157Index, 159vFigures1-1 US typhoid mortality and disease rates, 22-1 Vapor pressure of liquid chlorine, 102-2 Volumetemperature relation of liquid chlorine in a container loaded to its authorized l
17、imit, 113-1 Hypochlorous acid/hypochlorite distribution versus pH, 203-2 Breakpoint curve, 233-3 Disinfection versus free available chlorine residuals. Time scale is for 99.6 to 100 percent kill. Temperature was in the range of 20 to 29C, with pH as indicated, 293-4 Disinfection versus free availabl
18、e chlorine residuals. Time scale is for 99.6 to 100 percent kill. Temperature was in the range of 0 to 5C, with pH as indicated, 294-1 Chlorine cylinder, 324-2 Chlorine ton container, 324-3 Chlorine ton container truck, 324-4 Chlorine tank car, 334-5 Lifting beam with motorized hoist for ton contain
19、ers, 344-6 Ton containers stored on trunnions, 354-7 Chlorination feed equipment located in a separate room, 354-8 Two-cylinder scale, 364-9 Portable beam scale, 374-10 Combination trunnion and scale for a ton container, 374-11 Standard cylinder valves: poured-type fusible plug and screw-type fusibl
20、e plug, 384-12 Standard ton container valve, 384-13 Auxiliary tank valve connected directly to container valve, 394-14 Chemical induction mixers use a high-speed impeller to create a vacuum to draw the chemical, gas, or liquid into intimate contact with water to be treated. Some mixers have an open
21、impeller design and some are closed, 40vi4-15 Compound-loop control, 464-16 Perforated diffuser for pipelines larger than 3 ft (0.9 m) in diameter, 474-17 Chlorine scrubber test process flow and instrumentation diagram, 484-18 Chlorine scrubber system, 494-19 Example of total cylinder containment, 5
22、04-20 Chemical feed pump hydraulic drive, 514-21 On-site hypochlorite flow diagram, 524-22 On-site hypochlorite generation systems use only salt, water, and electric power to generate sodium hypochlorite, 544-23 Ammonia vacuum-feed systems with antipluggage options, 574-24 Truck delivery methods, 59
23、4-25 Typical horizontal aqua ammonia storage tank, 604-26 Automatic chlorine residual analyzer, 624-27 Automatic switchover unit, 644-28 Typical installation of switchover system, 644-29 Liquid chlorine changeover system, 654-30 Chlorine/ammonia vaporizer, 664-31 Chlorine vaporizer, 674-32 Propeller
24、 mixer in open channel flow showing location of baffles, 685-1 Air pack with positive-pressure mask, 755-2 Chlorine Institute emergency kit B, 836-1 Number of regulated contaminants, 1036-2 Impact of L/ W on T10/T ratio, 1056-3 Effect of perforated baffles on the T10/ T ratio of circular clearwells,
25、 1066-4 Examples of poor baffling conditions in basins, 1066-5 Examples of average baffling conditions in basins, 1076-6 Examples of superior baffling conditions in basins, 107vii6-7 Common chlorination points in a conventional filtration plant, 1116-8 Network map with potential booster chlorination
26、 locations, 1136-9 Breakpoint chlorination curve, 1146-10 Booster chlorination breakpoint curve, 1 hr incubation, 1146-11 Blend-residual curve for San Joaquin Reservoir chlorinated effluent and diemer chlorinated effluent (5 min contact time), 1156-12 Conventional treatment, surface water, 1176-13 D
27、irect and in-line filtration treatment, surface water, 1186-14 Dissolved air flotation/filtration treatment, surface water, 1186-15 Typical chlorinator deep-well installation showing booster pump, 1196-16 Zebra mussel sightings distribution as of 2004, 120A-1 “Bazooka” venturi dechlorination feeder,
28、 133A-2 Mat for dechlorination of trenches during main breaks, 134A-3 Diffuser for dechlorination of hydrant or blowoff waters, 134This page intentionally blank.ixTables1-1 Utilities with long experience of chloramines use, 52-1 Physical properties of chlorine, 112-2 Primary factors affecting sodium
29、 hypochlorite stability, 132-3 Half-life values of liquid bleach: varying temperature, pH, and concentration, 142-4 Physical properties of ammonia, 162-5 Properties of aqueous (aqua) ammonia, 30 percent by weight, 163-1 Chlorination disinfection by-products, 243-2 Common disinfection methods, 275-1
30、Chlorine exposure levels and effects on humans, 735-2 Summary of PPE recommendations for tasks involving potential exposure to gaseous or liquid chlorine, 785-3 Recommended criteria to evaluate selected PPE components for tasks involving liquid or gaseous chlorine, 785-4 Hazard summary for a hypothe
31、tical water system, 805-5 Typical emergency action checklist, 825-6 Summary of Hazmat responders training requirements, 835-7 Summary of PPE recommendations for tasks involving potential exposure to 320 percent sodium hypochlorite below 100F, 895-8 Recommended criteria to evaluate PPE components for
32、 tasks involving 320 percent sodium hypochlorite, 905-9 Physiological effects of ammonia, 916-1 Surface Water Treatment Rule disinfection requirements, 1046-2 Baffling classifications, 108A-1 Nonchemical dechlorination methods, 125A-2 Comparison of dechlorination agents, 126A-3 Dechlorination chemic
33、al reactions with free chlorine, 127xA-4 Dechlorination chemical reactions with chloramines, 128C-1 Calibrating comparator standard using potassium permanganate, 146C-2 Dilution table for various strengths of residual chlorine, 150C-3 Calculating free available chlorine from amperometric titration r
34、esults, 150C-4 Calculating free available chlorine from titration results, 153ForewordxiThis publication is the second edition of the American Water Works Association(AWWA) Manual M20; the original manual was titled Water Chlorination. This man-ual provides information on chlorination and chloramina
35、tion practices for the disinfec-tion of drinking water. It does not cover the use of chlorine as an oxidant or as adisinfectant for pipeline and appurtenances.The first edition was published in 1973 and was prepared to accompany anAWWA workshop on chlorination, which was part of a comprehensive oper
36、atorstraining program developed by an AWWA ad hoc committee and the AWWA Officeof Education.Major portions of the second edition have been adapted from two AWWA publica-tions: Water Treatment, second edition, Principles and Practices of Water Supply Oper-ations; and the Chlorination/Chloramination H
37、andbook by G.F. Connell. In addition,significant contributions were obtained (with permission) from publications of theChlorine Institute, the US Environmental Protection Agency, the Awwa ResearchFoundation, and the Handbook of Chlorination and Alternative Disinfectants, fourthedition, by Geo. Cliff
38、ord White. AWWA thanks the authors and publishers of theseresources for the use of their materials.This page intentionally blank.AcknowledgmentsxiiiA working group was formed to develop this edition of AWWA Manual M20, WaterChlorination/Chloramination Practices and Principles. The working group, whi
39、ch con-sists of experts in various areas of chlorination, was authorized by the AWWA Disin-fectants Standards Committee (213). It is due to their efforts that the first edition,published in 1973, was revised. Manual Workgroup MembersW.B. Huebner, U.S. Filter/Wallace (2) as “high-test calciumhypochlo
40、rite”; and (3) as chlorine bleach solutions (not to be confused with elementalliquid chlorine or with water solutions of chlorine gas).EVOLUTION OF CHLORINATION CONTROL PRACTICES_Improvements in chlorine disinfection materials and in chemical feeders substantiallycontributed to the popularity and wi
41、despread adoption of water chlorination. Origi-nally disinfection dosages were based largely on the application of fixed amounts ofchlorine. Soon it became apparent that provisions were not being made for the effectsof variations in water quality and the fluctuation in chlorine demand.Gradually, the
42、 concept of varying chlorine dosage on the basis of residual chlo-rine was established, and iodometric methods for qualitative and quantitative assayof residual chlorine were developed. The use of orthotolidine as a qualitative indicatorof residual chlorine was proposed in 1909, and later its use wa
43、s extended quantita-tively by the development of colorimetric standards. Between 1917 and 1919, chlorinedisinfection was established on a scientific basis when the suitability and reliability ofthe orthotolidine test for even the smallest water supplies were demonstrated. Sincethen, a better underst
44、anding of water chlorination processes has brought many refine-ments in that test and in the development of other tests, such as the orthotolidine-arsenitecolorimetric test to distinguish forms of residual chlorine, amperometric differential4 WATER CHLORINATION/CHLORAMINATION PRACTICES AND PRINCIPLE
45、Stitration, and various other differential chemical tests for available chlorine. In recentyears, the use of orthotolidine reagent has been discontinued in favor of the safer andmore stable N,N-diethyl-p-phenylenediamine (DPD) method. DPD is commonly usedboth for color comparison and titrimetric chl
46、orine testing.DISCOVERY OF TRIHALOMETHANES _As chlorination processes gained further acceptance, new discoveries were limited torefinements in the existing methods and chemistry (Connell 1996). It wasnt until the1970s that trace organic chlorination by-products were discovered. In Holland, Rookident
47、ified that the reaction of chlorine with organic materials dissolved in water pro-duced a class of compounds called trihalomethanes (THMs) (Connell 1996). Theorganics, usually humic and fulvic acids that originate in decaying vegetativegrowths, can be found in agricultural runoffs, aquifers, and nat
48、ural vegetation.The THMs were identified as possible cancer-causing agents, and their discoveryin drinking water raised concerns about chlorination. Research began on the nature ofthe reactions that produce THMs, the concentrations of THMs considered unaccept-able in drinking water, and methods to r
49、educe or prevent their formation. The greatrush of scientific work produced sufficient data to lead regulatory bodies in Europeand North America to set acceptable THM concentration levels in finished water andto determine ways to minimize THM formation in existing plants.HISTORICAL DEVELOPMENT OF CHLORAMINE_It is likely that chloramines formed accidentally in wastewater and in waters contain-ing natural ammonia for some time before this reaction was characterized. In theearly 1900s, the chlorine-ammonia combination rece
