1、 AWWA Standard SM Quicklime and Hydrated Lime Effective date: Aug. 1, 2013. First edition approved by AWWA Board of Directors Sept. 28, 1954. This edition approved June 9, 2013. Approved by American National Standards Institute May 31, 2013. ANSI/AWWA B202-13 (Revision of ANSI/AWWA B202-07) Copyrigh
2、t 2013 American Water Works Association. All Rights Reserved. ii AWWA Standard This document is an American Water Works Association (AWWA) standard. It is not a specification. AWWA standards describe minimum requirements and do not contain all of the engineering and administrative information normal
3、ly contained in specifications. The AWWA standards usually contain options that must be evaluated by the user of the standard. Until each optional feature is specified by the user, the product or service is not fully defined. AWWA pub- lication of a standard does not constitute endorsement of any pr
4、oduct or product type, nor does AWWA test, certify, or approve any product. The use of AWWA standards is entirely voluntary. This standard does not supersede or take precedence over or displace any applicable law, regulation, or codes of any governmental authority. AWWA standards are intended to rep
5、resent a consensus of the water supply industry that the product described will provide satisfactory service. When AWWA revises or withdraws this standard, an official notice of action will be placed on the first page of the Official Notice section of Journal - American Water Works Association. The
6、action becomes effective on the first day of the month following the month of Journal - American Water Works Association publication of the official notice. American National Standard An American National Standard implies a consensus of those substantially concerned with its scope and provisions. An
7、 American National Standard is intended as a guide to aid the manufacturer, the consumer, and the general public. The existence of an American National Standard does not in any respect preclude anyone, whether that person has ap - proved the standard or not, from manufacturing, marketing, purchasing
8、, or using products, processes, or procedures not conforming to the standard. American National Standards are subject to periodic review, and users are cautioned to obtain the latest editions. Producers of goods made in conformity with an American National Standard are encour - aged to state on thei
9、r own responsibility in advertising and promotional materials or on tags or labels that the goods are produced in conformity with particular American National Standards. Caution n oti Ce : The American National Standards Institute (ANSI) approval date on the front cover of this standard indicates co
10、mpletion of the ANSI approval process. This American National Standard may be revised or withdrawn at any time. ANSI procedures require that action be taken to reaffirm, revise, or withdraw this standard no later than five years from the date of ANSI approval. Purchasers of American National Standar
11、ds may receive current information on all standards by calling or writing the American National Standards Institute, 25 West 43rd Street, Fourth Floor, New York, NY 10036; (212) 642-4900, or emailing infoansi.org. ISBN-13, print: 978-1-58321-957-7 eISBN-13, electronic: 978-1-61300-240-7 All rights r
12、eserved. No part of this publication may be reproduced or transmitted in any form or by any means, 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
13、of the publisher. Copyright 2013 by American Water Works Association Printed in USA Copyright 2013 American Water Works Association. All Rights Reserved. iii The AWWA Standards Committee on Softening and Conditioning Chemicals, which reviewed and approved this standard, had the following personnel a
14、t the time of approval: Clyde R. Dugan, Chair General Interest Members W.J. Conlon, Parsons, Brinckerhoff Inc., Tampa, Fla. (AWWA) T.O. Crowley, Lees Summit, Mo. (AWWA) R. Casale,* Standards Council Liaison, American Water, Voorhees, N.J. (AWWA) S.J. Posavec,* Standards Group Liaison, AWWA, Denver,
15、Colo. (AWWA) B.H. Wilder, Daytona Beach, Fla. (AWWA) M.H. Winegard, Wheaton, Ill. (AWWA) Producer Members R.A. Brandau, General Chemical, Richmond, Va. (AWWA) D. Burnett, Burnett Inc., Campobello, S.C. (AWWA) J.M. Shepard, Middletown, Del. (AWWA) User Members I. Alvarez, John Preston Water Plant, Hi
16、aleah, Fla. (AWWA) C.R. Dugan, East Lansing Meridian Water Jan. 30, 1977; Jan. 30, 1983; June 19, 1988; June 6, 1993; Jan. 20, 2002, and Jan. 21, 2007. This edition of B202 was approved on June 9, 2013. I.C. Acceptance. In May 1985, the US Environmental Protection Agency (USEPA) entered into a coope
17、rative agreement with a consortium led by NSF International (NSF) to develop voluntary third-party consensus standards and a certification program for direct and indirect drinking water additives. Other members of the original consortium included the American Water Works Association Research Foundat
18、ion (AwwaRF, now Water Research Foundation) and the Conference of State Health and Environmental Managers (COSHEM). The American Water Works Association and the Association of State Drinking Water Administrators (ASDWA) joined later. In the United States, authority to regulate products for use in, o
19、r in contact with, drinking water rests with individual states. Local agencies may choose to impose requirements more stringent than those required by the state. To evaluate the health effects of products and drinking water additives from such products, state and local agencies may use various refer
20、ences, including two standards developed under the * American National Standards Institute, 25 West 43rd Street, Fourth Floor, New York, NY 10036. Persons outside the United States should contact the appropriate authority having jurisdiction. Copyright 2013 American Water Works Association. All Righ
21、ts Reserved. viii direction of NSF, NSF*/ANSI 60, Drinking Water Treatment ChemicalsHealth Effects, and NSF/ANSI 61, Drinking Water System ComponentsHealth Effects. Various certification organizations may be involved in certifying products in accor- dance with NSF/ANSI 60. Individual states or local
22、 agencies have authority to accept or accredit certification organizations within their jurisdiction. Accreditation of certi- fication organizations may vary from jurisdiction to jurisdiction. Annex A, “Toxicology Review and Evaluation Procedures,” to NSF/ANSI 60 does not stipulate a maximum allowab
23、le level (MAL) of a contaminant for substances not regulated by a USEPA final maximum contaminant level (MCL). The MALs of an unspecified list of “unregulated contaminants” are based on toxicity testing guidelines (noncarcinogens) and risk characterization methodology (carcinogens). Use of Annex A p
24、rocedures may not always be identical, depending on the certifier. ANSI/AWWA B202 addresses additives requirements in Sec. 4.3 of the standard. The transfer of contaminants from chemicals to processed water or to residual solids is becoming a problem of great concern. The language in Sec. 4.3.2 is a
25、 recommenda- tion only for direct additives used in the treatment of potable water to be certified by an accredited certification organization in accordance with NSF/ANSI 60, Drinking Water Treatment ChemicalsHealth Effects. However, users of the standard may opt to make this certification a require
26、ment for the product. Users of this standard should also consult the appropriate state or local agency having jurisdiction in order to 1. Determine additives requirements, including applicable standards. 2. Determine the status of certifications by parties offering to certify products for contact wi
27、th, or treatment of, drinking water. 3. Determine current information on product certification. II. Special Issues. II.A. Calcium Oxide. The amount of available calcium oxide (CaO) varies in limes. Many methods are available for evaluating the available CaO in lime. Some give consistently low result
28、s, some are rather time-consuming, and some do not give reproducible results. The method included in this standard is reasonably rapid and reproducible and gives results that are consistent with the available CaO content obtained in use in water treatment. Other methods may be used. The method of an
29、alysis for available CaO content presented in this standard has been found by many users to be satisfactory as a basis for the purchase of lime for water treatment. Usable results will be obtained by this method only if the acid is carefully * NSF International, 789 N. Dixboro Road, Ann Arbor, MI 48
30、105. Copyright 2013 American Water Works Association. All Rights Reserved. ix standardized according to the instructions in this standard and only if the procedure for the specified test is followed in exact detail. Some water utility personnel still believe that a better evaluation of lime can be m
31、ade and that more accurate results can be obtained by determining total CaO. In addition to available CaO, such an analysis determines CaO present as calcium car- bonatea factor of little importance in water treatment. For those who prefer the total CaO method, and for those who wish to make a compl
32、ete analysis, the methods outlined in ASTM* C25, Standard Test Methods for Chemical Analysis of Limestone, Quicklime, and Hydrated Lime, are recommended. The amount of available CaO varies in limes from different geographic regions. Factors such as source of rock, manufacturing conditions, type of k
33、iln, type of fuel, and even personnel have an effect on product quality. II.B. Lime. A lime that slakes at a rate consistent with plant equipment is more economical to use and less difficult to handle. A slaking-rate test to determine the reactivity of lime is included in this standard. This procedu
34、re was devised to control the variables that occur in the test, thus improving the reproducibility of results. The results of the slaking-rate test on a given quicklime should be correlated with the performance of the lime in the slaker. The slaking requirement for the lime can then be specified. Be
35、cause most modern lime-slaking equipment contains devices for the removal of grit, sand, pebbles, and other coarse inert material and because overloading of the grit- removing devices is undesirable, a test for insoluble matter is provided in this standard. II.C. Magnesium and Insoluble Material. Th
36、is standard sets no limit on magnesium because keeping the available CaO content within the specified limit should address any excess magnesium problem adequately. No provision is made for high-magnesium lime for the specific reason that such lime is not suited for water treatment. Although insolubl
37、e matter (iron and aluminum) can cause turbidity when lime is applied to filtered water or to a water supply not to be filtered, no limit is set for these constituents because turbidity problems can be overcome by adding the lime as a saturated solution. If such a procedure is impractical, individua
38、l treatment plants may need to set up limits for total insoluble matter, iron, and aluminum when purchasing lime. This condition occurs so rarely that a provision for it in this standard is unwarranted. The test for insolubles included in this standard determines only those insolubles that are coars
39、e enough to be retained in the slaker or grit remover. Likewise, * ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. Copyright 2013 American Water Works Association. All Rights Reserved. x no mention is made of the character of insoluble matter, assuming that its composition wi
40、ll not affect the application of lime if done using a dry-feed machine. II.D. Size and Marking. Sizes of lime are established in the standard to meet the requirements of various types of feed equipment. Alternatively, purchasers may set size requirements to meet specific conditions. A change in size
41、 requirements should be made only after consultation with the manufacturer of the feed equipment being used. The standard also does not require the date of manufacture to be stamped on the bags in which the hydrated lime is shipped; it is assumed that the material will be delivered to the point of u
42、se in a condition to be handled readily in a dry-feed machine. II.E. Purchase Basis. This standard describes only limes composed mainly of calcium oxide or calcium hydroxide. Special limes, such as dolomitic limes for the removal of silica, are not included. Thus, for the purchase of lime of a diffe
43、rent chemical composition, the purchaser must provide specifications describing the kind of material desired. For lime of any type, the purchaser may specify the method of manufacture to be used in making the lime. Lime should be purchased according to the following industry-recommended guidelines:
44、1. Quicklime. In general, quicklime contains about 90 percent available CaO in the material provided, although greater or lower percentages of available CaO can be used. The quicklime should slake satisfactorily, based on the systems design. Satisfactory “quick-slaking” lime will usually produce a t
45、emperature rise of 40C (72F) in 3 min, and the slaking reaction will be complete in 10 min or less when the lime is tested according to Sec. 5.4 of this standard. Satisfactory quicklime for water treatment will slake without production of objec- tionable amounts of insoluble material. 2. Hydrated li
46、me. In general, hydrated lime contains 68 percent available CaO (which is equivalent to 89.8 percent calcium hydroxide) content in the material provided, although higher or lower percentages of available CaO can be used. II.F. Sampling. Production-statistical process control testing is being used in
47、creasingly as a substitute for per-load sampling and testing and may be used as an alternative. Current good laboratory practices require documentation of the handling of all samples from the time they are first collected until they are introduced as evidence in possible legal proceedings. Chain-of-custody procedures are followed to maintain and document control of sample possession. An in-depth discussion of chain-of-custody Copyright 2013 American Water Works Association. All Rights Reserved.
