AWWA 20657-2009 Chemical Feed Field Guide for Treatment Plant Operators Calculations and Systems.pdf

1、 #MBOL1BHFChemical Feed Field Guide for Treatment Plant OperatorsCalculations and Systemsby William C. Lauer, Michael G. Barsotti, and David K. HardyChemical Feed Field Guide for Treatment Plant Operators: Calculations and SystemsCopyright 2009 American Water Works AssociationAWWA Publications Manag

2、er: Gay Porter De NileonSenior Technical Editor: Melissa Valentine Technical Editor/Project Manager: Martha Ripley GrayProduction Editor: Cheryl ArmstrongCover Art: Daniel FeldmanAll rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic

3、 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.DisclaimerThe authors, contributors, editors, and publisher do not assume responsibility for

4、 the validity of the content 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 information presented in this book. In particular, AWWA will not be responsible for any costs, including, but n

5、ot limited to, those incurred as a result of lost revenue. In no event shall AWWAs liability exceed the amount paid for the purchase of this book.6666 West Quincy AvenueDenver, CO 80235-3098303.794.7711Library of Congress Cataloging-in-Publication DataLauer, Bill.Chemical feed field guide for treatm

6、ent plant operators : calculations and systems / William C. Lauer, Michael G. Barsotti, David K. Hardy.p. cm.Includes bibliographical references and index.ISBN-13: 978-1-58321-588-3ISBN-10: 1-58321-588-31. Drinking water-Purification-Materials. 2. Drinking water-Purification-Mathematics. 3. Feedstoc

7、k. 4. Materials handling-Mathematics. 5. Engineering mathematics-Formulae. 6. Chemical process control. I. Barsotti, Michael G. II. Hardy, David K. III. Title.TD451.L38 2008628.166-dc222008044305iiiTable of ContentsList of Figures vList of Tables viiAbout the Authors ixForeword xiAcknowledgments xii

8、iChemical Feed Quality Control Chapter 1. 1Quality Control Leads to Quality Assurance 1Chemical Selection and Dosage Determination 3Chemical Purchasing Specifications 5Storage Considerations Affecting Chemical Feed 9Feed Equipment Calibration or Verification 9Feed Rate Adjustment and Equipment Accur

9、acy 10Chemical Inventory Control 12Chemical Addition and Mixing 12Chemical Feed Locations and Timing 13Quality Control at Each Step 13Chemical FeedCommon System Components 1Chapter 2. 5Conveyance 15Dispersion 18Dosage Control 23Chemical Feed of GasesEquipment and Systems 2Chapter 3. 7Chemical Detail

10、s 27Delivery and Handling 31Chemical Feeders 31Gas Feed Systems 33Feeding Gases in Water Treatment 38Chemical Feed of GasesCalculations and Examples 3Chapter 4. 9Gas Feed Directly into the Water Flow 39Ozone Feed Calculations 42Oxygen Feed System Calculation Examples 43Air Feed System Calculation Ex

11、amples 44Chlorine Dioxide Feed Calculations 46Chlorine and Sodium Chlorite Feed Calculators 48Dry Chemical Feeders and Systems 5Chapter 5. 5Chemical Storage and Handling 59Chemical Feeders 60ivCalibration Devices 62Solution Systems 64Dry Chemical FeedCalculations and Examples 6Chapter 6. 7Full-Stren

12、gth Chemical Feed Calculations 67Percent Active Ingredient Chemical Feed Calculations 68Solution Preparation Using Dry Chemicals: Batch Preparation Calculations 70Chemical Usage and Inventory Control 72Liquid Chemical Feed Equipment and Systems 7Chapter 7. 5Chemical Receiving and Storage 76Liquid Ch

13、emical Feed Equipment 77Liquid Chemical Feed Systems 81On-Site Hypochlorite Generation and Feed Systems 84Polymer Feed Systems 85Metering Pump Calibration 89Feeding Liquid Chemicals in Water Treatment 93Liquid Chemical FeedCalculations and Examples 9Chapter 8. 5Direct Feed Calculations 95Diluted Che

14、mical Feed Calculations 97Relationship of Density to Specific Gravity 99Chemical Feed Rate Calculation Examples 102Calculation Starting with Different Units 103Inventory Management for Liquid Chemicals 104Chemical Feed in Dilution Tank Systems (Two-Tank Systems) 107Appendix A: Chemical Specification

15、 Example Language 111Appendix B: Conversion Factors 115Conversion of US Customary Units 115Metric Conversions 119Appendix C: Density Tables For Common Liquid Chemicals 125Appendix D: Calculator Derivations 135Gas Chemical Feed Calculators 135Dry Chemical Feed Calculators 141Liquid Chemical Feed Calc

16、ulators 142Appendix E: Atomic Weights of Elements 147References 151vList of FiguresFigure 1-1 Conventional water treatment plant with typical chemical addition locations 3Figure 1-2 Locked chemical fill station 7Figure 1-3 Reading a hydrometer 8Figure 1-4 Chemical feeder calibration chart 11Figure 2

17、-1 Chemical feed system, common components 15Figure 2-2 Liquid chemical gravity feed system 16Figure 2-3 Liquid chemical feed system using dilution water 17Figure 2-4 Venturi injector 18Figure 2-5 Perforated pipe diffuser 19Figure 2-6 Simple pipe diffuser made from Schedule 80 PVC 19Figure 2-7 Open

18、channel diffuser 19Figure 2-8 Multiple blade mechanical mixer 20Figure 2-9 In-line mechanical mixer 21Figure 2-10 Single-blade mechanical mixer 21Figure 2-11 Types of chemical mixers: (a) pump diffusion, (b) static, (c) venturi 22Figure 2-12 Computer SCADA control screens 23Figure 2-13 Large control

19、 center for public utilities 23Figure 2-14 Flow pacing (feedforward) control system 25Figure 2-15 MicroTSCM streaming current analyzer 26Figure 3-1 Chlorine cylinder connection illustration 31Figure 3-2 Cabinet chlorinator 32Figure 3-3 Rotameter close-up 33Figure 3-4 150-lb cylinder chlorination sys

20、tem 33Figure 3-5 Cylinder-mounted chlorinator 34Figure 3-6 Well chlorination system 34Figure 3-7 Cylinder mounted automatic switchover system 35Figure 3-8 Chlorination storage and feed room 35Figure 3-9 Ozone generator 37Figure 3-10 Ozone system 37Figure 3-11 Chlorine dioxide generation system; Chlo

21、rine gas/chlorite solution 38Figure 5-1 Typical dry chemical feed system 60Figure 5-2 Typical quicklime feed system 60Figure 5-3 Dry chemical storage tank 61Figure 5-4 Permanganate drum hopper 62Figure 5-5 Volumetric feeder 63Figure 5-6 Gravimetric feeder 63Figure 5-7 Calibration chart (example 5-1)

22、 66Figure 5-8 Dry chemical (polymer) solution system 67Figure 7-1 Typical liquid chemical feed system 78Figure 7-2 Metering pump flow compared to centrifugal pump 80viFigure 7-3 Piston pump 80Figure 7-4 Diaphragm pump 81Figure 7-5 Gear pump 81Figure 7-6 Chemical metering pump installation with pulsa

23、tion dampener 82Figure 7-7 Liquid chemical feed systems 83Figure 7-8 Chemical dilution tank 84Figure 7-9 On-site hypochlorite generation system 85Figure 7-10 On-site hypochlorite generator system 86Figure 7-11 Metering pump calibration chamber installation 92Figure 7-12 Calibrating a metering pump 9

24、3Figure 7-13 Metering pump with calibration chamber 93Figure 7-14 Alum pump calibration chart 95Figure 8-1 Chemical usage deducted from storage (example) 109viiList of TablesTable 1-1 Common chemicals used in water treatment 2Table 1-2 Examples of specific gravity requirements for common liquid chem

25、icals 8Table 1-3 Common water treatment chemicals with storage issues 9Table 3-1 Common gases used in water treatment 28Table 4-1 Flow conversions 43Table 4-2 Feed rate conversions 44Table 4-3 Chlorine dioxide feed (for 1 mg/L dosage) 49Table 5-1 Common dry chemicals used in water treatment 58Table

26、5-2 Calibration results (example 5-1) 65Table 6-1 Dry chemical amount (lb) to prepare solutions 73Table 6-2 Dry chemical amount (kg) to prepare solutions 73Table 6-3 Reorder trigger inventory amountdays of inventory for amount in pounds (lb) or tons 76Table 7-1 Common liquid chemicals used in water

27、treatment 77Table 7-2 Liquid water treatment chemicalsspecial storage considerations (examples) 79Table 7-3 Pump rate conversion 94Table 8-1 Conversion factors for common feed rate units 98Table 8-2 Chemical feed daily usage conversion factors 107Table 8-3 Liquid chemical usage and deduction from st

28、orage example 108Table C-1 Properties of liquid alum 127Table C-2 Densities and weight equivalents of standard alum solutions 128Table C-3 Temperature corrections for standard alum solutions (specific gravity over 1.28) 130Table C-4 Sodium hypochlorite specific gravity table 132Table C-5 Percent hyd

29、rofluosilicic acid (H2SiF6) vs. density chart 60C 132Table C-6 Densities of pure (salt free) caustic soda solution (volumetric units) at 20C (68F) 133Table C-7 Specific gravity, boiling points, and freezing points of various aqua ammonia solutions 135Table D-1 Ozone dosage calculation spreadsheet ex

30、ample: oxygen feed 138Table D-2 Ozone dosage calculation spreadsheet example: air feed 140viiiixAbout the AuthorsWilliam C. LauerWilliam C. Lauer is senior technical services engineer for the American Water Works Association (AWWA). Mr. Lauer has written and edited more than a dozen books and 50 art

31、icles and technical publications covering all aspects of the drinking water industry, including water quality, treatment, reuse, distribution system operation, management, and desalting. He is a recognized technical expert in the field and has consulted for NASA, US En-vironmental Protection Agency,

32、 the Government of Singapore, several ma-jor engineering design and construction firms, and many others in his more than 30 years in the drinking water supply field.Michael G. BarsottiMichael G. Barsotti is director of water quality and production for Cham-plain Water District in northwestern Vermon

33、t. Mr. Barsotti has written several papers addressing treatment facility optimization and has actively served the Partnership for Safe Water Program and the AWWA New Eng-land Water Works Filtration Committee. In addition, Mr. Barsotti has served several years as a state regulator. He has more than 2

34、2 years experience in drinking water treatment plant operations and water quality management. David K. HardyDavid K. Hardy is manager of the Utah Valley Water Treatment Plant for the Central Utah Water Conservancy District. David has been involved in the operations of water treatment plants since 19

35、85. He served as a plant operator for 12 years and treatment plant manager for the past 11 years. He considers his most important title to be “operator” and continues to operate the plant, with frequency, to “feed his roots.” His strengths are in his knowl-edge of process control and treatment plant

36、 optimization. The Utah Valley Plant and staff are recipients of the Partnership for Safe Water Phase IV Award of Excellence.xiForewordThis chemical feed operators field guide is one of the “Field Guide” se-ries of books published by the American Water Works Association (AWWA). These books are meant

37、 to be small, practical, how-to publications on specific subjects of importance to drinking water system operating personnel. These books omit most of the theory and background that have led to the use of the procedures described in the guides. This fundamental information is found in other AWWA pub

38、lications and is referenced in the field guides. This field guide, like the other books in this series, provides the infor-mation needed to do the work. Useful tables and easy-to-follow illustrations help system operators perform the chemical feed procedures described in the references. Field guides

39、 get straight to the point and provide the neces-sary information to perform the most common procedures. This approach leads the operator to the most useful solutions without needlessly complicat-ing the issue with every possibility.There are several special notes included throughout the book. Look

40、for “Ops Tips” and the “Table Tamer” in callouts and text boxes for some help with important points and how to use some of the tables. There are also many “calculators” that help plug in the numbers needed to calculate a value.“Calculators” provide easy-to-use, plug-in-the-numbers equations and exam

41、ples that are used to give quick results. The conversion factors and other constants have been combined so that the equation is greatly simpli-fied. The derivation of the formula is not given, just the result. More detail about the source of the constants shown for the calculators is shown in Ap-pen

42、dix D.Ops TipOperator Tips point out important points in the text. Table TamerIllustrates how to use some of the more complicated tables.xiiUse calculator cX-xCalculation result and units of measure= Constant Insert known value needed for the calculationSource water quality differences and treatment

43、 processes control the optimum chemical treatment at a given location. Accurately and precisely feeding water treatment chemicals is critical to production of high quality drinking water. The authors hope this information is helpful and is used to supplement hands-on training and thus becomes an ind

44、ispensable compan-ion for water treatment plant operations personnel.William C. LauerMichael G. BarsottiDavid K. HardyxiiiAcknowledgmentsThe authors wish to thank the following reviewers who provided the benefit of their experience to enhance this publication. William Soucie, Central Lake County Joi

45、nt Action Water Agency, Lake Bluff, Ill.David Tuck, Greenwood Commissioners of Public Works, Green-wood, S.C.Specific advice was provided regarding ozone feed calculations by Kerwin Rakness (Process Applications Incorporated). Suggestions and comments on chlorine dioxide feed were provided by Kevin

46、Gertig and Grant Jones (both with the City of Fort Collins, Colo.).Thank you also to the publication department at AWWA. The professionalism of our editors, Martha Ripley Gray and Melissa Valentine, greatly enhanced the quality of this field guide.11Chapter Chemical Feed Quality ControlWater treatme

47、nt plants use chemicals to remove contaminants, improve taste and appearance, and satisfy regulatory requirements. Accurate delivery of these chemicals to the point of application is critical to maintain and assess plant performance, to control the cost of treatment, and to predict the need for more

48、 supplies.Many chemicals are used in water treatment. Table 1-1 lists the most common chemicals. The table groups chemicals by the most prevalent use, although some chemicals are used for several purposes.Many chemical feed locations exist in a treatment plant. Rapid dispersion of coagulants occurs

49、in the rapid mix chamber. Polymer filter aids are added just prior to filtration or even on top of the fil-ters. Injecting disinfection chemicals after filtration reduces unde-sirable by-products. Stabilization of the water provides corrosion control as the water enters the distribution system (Figure 1-1). A careful match of the feed location with the correct chemical leads to peak treatment plant performance.Quality Control Leads to Quality AssuranceDr