1、ANSI/AWWA B408-18(Revision of ANSI/AWWA B408-10)AWWA StandardSMLiquid Polyaluminum ChlorideEffective date: May 1, 2018.First edition approved by AWWA Board of Directors Jan. 31, 1993.This edition approved Jan. 20, 2018.Approved by American National Standards Institute Sept. 28, 2017.Copyright 2018 A
2、merican Water Works Association. All Rights Reserved. iiAWWA StandardThis 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 normally contain
3、ed 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 publication of a standard does not constitute endorsement of any product or pro
4、duct 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 code of any governmental authority. AWWA standards are intended to represent a cons
5、ensus of the water industry that the product described will provide satisfactory service. When AWWA revises or withdraws this standard, an official notice of action will be placed in the Official Notice section of Journal - American Water Works Association. The action becomes effective on the first
6、day of the month following the month of Journal AWWA publication of the official notice.American National StandardAn American National Standard implies a consensus of those substantially concerned with its scope and provisions. An American National Standard is intended as a guide to aid the manufact
7、urer, the consumer, and the general public. The existence of an American National Standard does not in any respect preclude anyone, whether that person has approved the standard or not, from manufacturing, marketing, purchasing, or using products, processes, or procedures not conforming to the stand
8、ard. 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 encouraged to state on their own responsibility in advertising and promotional materials or on tags or
9、labels that the goods are produced in conformity with particular American National Standards.Caution notiCe: The American National Standards Institute (ANSI) approval date on the front cover of this standard indicates completion of the ANSI approval process. This American National Standard may be re
10、vised 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 Standards may receive current information on all standards by calling or writing the Am
11、erican National Standards Institute, 25 West 43rd Street, Fourth Floor, New York, NY 10036; 212.642.4900; or e-mailing infoansi.org.ISBN-13, print: 978-1-62576-286-3 eISBN-13, electronic: 978-1-61300-467-8DOI: http:/dx.doi.org/10.12999/AWWA.B408.18All rights reserved. No part of this publication may
12、 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 of the publisher.Copyright 2018 by Ameri
13、can Water Works Association Printed in USACopyright 2018 American Water Works Association. All Rights Reserved. iiiCommittee PersonnelThe AWWA Standards Committee on Iron Salts, Aluminum Salts, and Related Coagulant Aids, which reviewed and approved this standard, had the following personnel at the
14、time of approval:Glenn R. Evers, ChairJan J. Pavlicek, Vice-ChairGeneral Interest MembersK.-K. Au, FMC Global Peroxychem, Naperville, Ill. B. Bickerton, CBCL Limited, Halifax, N.S., Canada N.J. Edman,*Standards Group Liaison, AWWA, Denver, Colo. J.D. Edwards, Westerville, Ohio G.R. Evers, IS2 LLC, H
15、ockessin, Del. J.J. Gemin, AECOM, Kitchener, Ont., Canada P.H. Hargette, Black spillage may cause a fire or liberate dangerous gases.3. Sodium chloride solution, standard, 0.05N. Dry approximately 3.1 g ofsodium chloride in a weighing dish in an oven at 105110C for 2 h. Cool the crystals to room tem
16、perature in a desiccator.Weigh 2.9221 g of the dried sodium chloride to the nearest 0.0001 g in a tared weighing bottle. Using a water-wash bottle, quantitatively transfer the crystals through a powder funnel into a 1,000-mL volumetric flask. Add about 150 mL deionized water and swirl to dissolve th
17、e crystals. Dilute to the mark at 20C with deionized water and mix thoroughly. Store the solution in a polyethylene bottle.4. Iron indicator solution. To a 1,500-mL beaker add 62 g ferric ammoniumsulfate, FeNH4(SO4)212H2O, and 500 mL of deionized water. Stir until the crystals are dissolved. Add 438
18、 mL concentrated nitric acid and mix. Store the solution in a polyethylene bottle.5. Potassium thiocyanate solution, 0.05N. Weigh 4.86 g potassiumthiocyanate to the nearest 0.01 g in a tared weighing bottle. Quantitatively transfer the crystals through a powder funnel into a 1,000-mL volumetric flas
19、k. Add about 250 mL deionized water and swirl to dissolve the crystals. Dilute to the mark with deionized water and mix thoroughly. Store the solution in a polyethylene bottle.Copyright 2018 American Water Works Association. All Rights Reserved. LIQUID POLYALUMINUM CHLORIDE 136. Benzyl alcohol. Disp
20、ense from an amber-glass dropping bottle.Caution: Benzyl alcohol vapor is irritating to the eyes, nose, and throat; the liquid can burn skin and eyes and also may be readily absorbed through the skin. It is combustible. Keep the reagent away from heat or flame.7. Silver nitrate solution, standard 0.
21、05N. Weigh 8.495 g silver nitrate tothe nearest 0.001 g in a tared weighing bottle. Quantitatively transfer the crystals through a powder funnel into a 1,000-mL volumetric flask. Add about 250 mL deionized water and swirl to dissolve the crystals. Dilute to the mark with deionized water and mix thor
22、oughly. Store the solution in a tightly stoppered amber-glass bottle. Standardize the solution as follows:a. Pipette 25.0 mL of the standard 0.05N sodium chloride solutioninto each of three 500-mL glass-stoppered Erlenmeyer flasks. Determine the temperature of the sodium chloride solution and correc
23、t the volume pipetted to 20C (Sec. 5.7.5Item 3 and Table 2). Carry each flask through the remaining steps of the procedure.Table 2 Temperature corrections for volumetric solutionsTemperature mL Correction per mL Used* FactorC N/20 or lesssolutionsN/10solutionsN/1solutionsN/20 or lesssolutionsN/10sol
24、utionsN/1solutions15 +0.0008 +0.0008 +0.0011 1.0008 1.0008 1.001116 +0.0006 +0.0007 +0.0009 1.0006 1.0007 1.000917 +0.0005 +0.0005 +0.0007 1.0005 1.0005 1.000718 +0.0003 +0.0004 +0.0005 1.0003 1.0004 1.000519 +0.0002 +0.0002 +0.0003 1.0002 1.0002 1.000320 0.0000 0.0000 0.0000 1.0000 1.0000 1.000021
25、0.0002 0.0002 0.0003 0.9998 0.9998 0.999722 0.0004 0.0004 0.0005 0.9996 0.9996 0.999523 0.0006 0.0006 0.0008 0.9994 0.9994 0.999224 0.0008 0.0009 0.0012 0.9992 0.9991 0.998825 0.0010 0.0011 0.0015 0.9990 0.9989 0.998526 0.0013 0.0013 0.0018 0.9987 0.9987 0.998227 0.0015 0.0016 0.0022 0.9985 0.9984 0
26、.997828 0.0018 0.0019 0.0025 0.9982 0.9981 0.997529 0.0020 0.0021 0.0029 0.9980 0.9979 0.997130 0.0023 0.0024 0.0033 0.9977 0.9976 0.9967* Apply correction to mL used to obtain corrected volume, or multiply factor by mL used to obtain corrected volume.Multiply factor by mL used to obtain corrected v
27、olume.Copyright 2018 American Water Works Association. All Rights Reserved. 14 AWWA B408-18b. Add 100 mL deionized water and 5 mL iron indicator solution. Swirlto mix. Using a 50-mL class A burette, add 27.0 mL of the silver nitrate solution being standardized while swirling vigorously. Record the e
28、xact volume of the silver nitrate solution added to the nearest 0.01 mL, determine its temperature, and correct the volume to 20C (Sec. 5.7.5Item 3 and Table 2).c. Add 10 drops benzyl alcohol, stopper the flask, and shake it vigorouslyfor 30 s. Place a 500-mL Erlenmeyer flask beneath a long-stem fun
29、nel fitted with Whatman 42 or equivalent filter paper. Transfer the contents from the stoppered flask to the funnel. Rinse this flask with about 5 mL of deionized water, stopper the flask, and thoroughly shake the rinse water around in the flask. Transfer the rinse water to the filter. Repeat the ri
30、nsing and the transfer of the rinse water. A complete transfer of the precipitate to the filter is not necessary. Wash the precipitate on the filter twice with cold water and collect the washings with the filtrate. Using a class A burette, slowly and while constantly swirling, titrate the combined f
31、iltrate, rinse water, and washings with 0.05N potassium thiocyanate solution until a faint red color persists.(Eq 7)d. Determine the factor F2as follows: Add about 9 mL of the silver nitratesolution from the 50-mL burette to a 250-mL Erlenmeyer flask. Add 100 mL water and 5 mL iron indicator solutio
32、n. Swirl to mix. Titrate slowly with the KSCN solution from the 10-mL burette while swirling constantly until a faint reddish color persists.e. Average the three results.f. Restandardize monthly.(Eq 8)g. Repeat the determination and use the average factor rounded off to thenearest 0.001-mL AgNO3/mL
33、KSCN. Determine F2each time a new KSCN or AgNO3solution is prepared.5.7.2 Apparatus.1. Analytical balance accurate to 0.0001 g.2. Weighing dish.3. Drying oven.normality of AgNOmL NaCl at 20 C) (0.0500)(mL AgNO a33=(tt 20 C) (mL KSCN )2 FF23mL AgNOmL KSCN=Copyright 2018 American Water Works Associati
34、on. All Rights Reserved. LIQUID POLYALUMINUM CHLORIDE 154. Desiccator.5. 1,500-mL beaker.6. 1,000-mL volumetric flask.7. 500-mL Erlenmeyer flask with stoppers.8. 50-mL class A burette.9. 50-mL pipette.10. 250-mL Erlenmeyer flask.11. 250-mL beaker.12. 100-mL volumetric flask.5.7.3 Procedure.Note: Ani
35、ons, such as bromide, iodide, ferricyanide, ferrocyanide, andthiocyanate, which form silver salts that are less soluble than silver chloride in dilute nitric acid solution, are also titrated and give rise to positive interference. None of these anions is expected to be present in the sample in signi
36、ficant amounts.Bivalent mercury causes negative interference by forming a stable complex with thiocyanate ion.1. Weigh 4 g of the sample to the nearest 0.001 g in a 250-mL beaker. Diluteto about 50 mL with deionized water. Acidify with 5 mL concentrated nitric acid and boil for 5 min. Cool and trans
37、fer the sample to a 100-mL volumetric flask and dilute to volume. Pipette 10.00 mL of this solution to a 500-mL glass-stoppered Erlenmeyer flask and dilute to about 150 mL with deionized water.2. Add 5 mL iron indicator solution to the flask. Swirl to mix.3. From a zeroed 10-mL class A burette, add
38、1.0 mL 0.05N potassiumthiocyanate solution and swirl to mix. Do not rezero this burette; the titration with thiocyanate solution will continue in Sec. 5.7.3(Item 8).4. Fill and zero a 50-mL class A burette with standard 0.05N silver nitratesolution. Titrate slowly while swirling vigorously until the
39、 red color is completely discharged. Add an additional 2 mL standard 0.05N silver nitrate solution. Record the exact volume of silver nitrate solution to the nearest 0.01 mL.5. Add 10 drops benzyl alcohol, stopper the flask, and shake it vigorouslyfor 30 s (see note, Sec. 5.5.3).6. Place a 500-mL Er
40、lenmeyer flask beneath a long-stem funnel fitted withWhatman 42 or equivalent filter paper.7. Transfer the contents from the stoppered flask to the funnel. Rinse thisflask and thoroughly shake the rinse water around in the flask. Transfer the rinse water to the filter. Repeat the rinsing and the tra
41、nsfer of the rinse water. A complete Copyright 2018 American Water Works Association. All Rights Reserved. 16 AWWA B408-18transfer of the precipitate to the filter is not necessary. Wash the precipitate on the filter twice with cold water and collect the washings with the filtrate.8. Using the 10-mL
42、 burette from which KSCN was added inSec. 5.7.3(Item 3), slowly and with constant swirling titrate (without rezeroing) the filtrate with 0.05N potassium thiocyanate solution until a faint red color persists (see notes, Sec. 5.7.5).5.7.4 Calculation.(Eq 9)5.7.5 Notes and temperature corrections for v
43、olumetric solutions.1. Shaking with benzyl alcohol facilitates filtration by coagulating theprecipitate.2. A back-titration of at least 0.5 mL KSCN solution is necessary to ensurethat an adequate excess of silver nitrate solution is present to completely precipitate the chloride present in the sampl
44、e.3. When volumetric solutions are standardized at 20C, titrations shouldbe made at this temperature or corrections applied to reduce the volume of the solution used in titrations to 20C.Sec. 5.8 Notice of NonconformanceIf the liquid PACl product delivered to the purchaser does not meet the chemical
45、, physical, safety, or security requirements of this standard, the purchaser shall provide a notice of nonconformance to the supplier within 10 days after receipt of the shipment at the point of destination. The results of the purchasers tests shall prevail unless the supplier notifies the purchaser
46、 within 5 days after receipt of the notice of nonconformance that a retest is desired. On receipt of the request for a retest, the purchaser shall forward to the supplier one of the sealed samples taken in accordance with Sec. 5.1. If the results obtained by the supplier on retesting do not agree wi
47、th the test results obtained by the purchaser, the other sealed sample shall be forwarded, unopened, for analysis to a referee laboratory agreed on by both parties. The results of the referee analysis shall be accepted as final.Material not complying with the requirements of this standard and the purchasers documents may be rejected. Replacement and retesting shall be accomplished in accordance with the purchasers documents.chloride, as percent Cl mL AgNO) (mL KSCN ) (32=( F NN of AgNO )(3.545)grams of sample 10/1003Copyright 2018 American Water Works Association. All Rights Reserved.
