PHYSICAL–CHEMICAL TREATMENT OF WATER AND WASTEWATER CRC PRESS Boca Raton London New York Washington, D.C. PHYSICAL–CHEMICAL TREATMENT OF WATER AND WASTEWATER Arcadio P. Sincero Sr., D.Sc., P.E. Morgan State University Baltimore, Maryland Gregoria A. Sincero, M. Eng., P.E. Department of the Environment State of Maryland This book contains information obtained from authentic and highly regarded sources. Reprinted material is quoted with permission, and sources are indicated. A wide variety of references are listed. Reasonable efforts have been made to publish reliable data and information, but the author and the publisher cannot assume responsibility for the validity of all materials or for the consequences of their use. Neither this book nor any part may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, microfilming, and recording, or by any information storage or retrieval system, without prior permission in writing from the publisher. The consent of CRC Press LLC does not extend to copying for general distribution, for promotion, for creating new works, or for resale. Specific permission must be obtained in writing from CRC Press LLC for such copying. Direct all inquiries to CRC Press LLC, 2000 N.W. Corporate Blvd., Boca Raton, Florida 33431. Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation, without intent to infringe. Visit the CRC Press Web site at www.crcpress.com © 2003 by A. P. Sincero and G. A. Sincero Co-published by IWA Publishing, Alliance House, 12 Caxton Street, London, SW1H 0QS, UK Tel. +44 (0) 20 7654 5500, Fax +44 (0) 20 7654 5555 publications@iwap.co.uk www.iwapublishing.com ISBN 1-84339-028-0 No claim to original U.S. Government works International Standard Book Number 1-58716-124-9 Library of Congress Card Number 2002023757 Printed in the United States of America 1 2 3 4 5 6 7 8 9 0 Printed on acid-free paper Library of Congress Cataloging-in-Publication Data Sincero, Arcadio P. (Arcadio Pacquiao) Physical–chemical treatment of water and wastewater / Arcadio Pacquiao Sincero, Sr., Gregoria Alivio Sincero. p. cm. Includes bibliographical references and index. ISBN 1-58716-124-9 (alk. paper) 1. Water—Purification. 2. Sewage—Purification. I. Sincero, Gregoria A. (Gregoria Alivio) II. Title TD430 .S47 2002 628.1 ′ 62—dc21 2002023757 TX249_Frame_CFM.fm Page 4 Wednesday, June 19, 2002 1:28 PM Preface This textbook is intended for undergraduate students in their junior and senior years in environmental, civil, and chemical engineering, and students in other disciplines who are required to take the course in physical–chemical treatment of water and wastewater. This book is also intended for graduate students in the aforementioned disciplines as well as practicing professionals in the field of environmental engi- neering. These professionals include plant personnel involved in the treatment of water and wastewater, consulting engineers, public works engineers, environmental engineers, civil engineers, chemical engineers, etc. They are normally employed in consulting firms, city and county public works departments, and engineering depart- ments of industries, and in various water and wastewater treatment plants in cities, municipalities, and industries. These professionals are also likely to be employed in government agencies such as the U.S. Environmental Protection Agency, and state agencies such as the Maryland Department of the Environment. The prerequisites for this textbook are general chemistry, mathematics up to calculus, and fluid mechanics. In very few instances, an elementary knowledge of calculus is used, but mostly the mathematical treatment makes intensive use of algebra. The entire contents of this book could be conveniently covered in two semesters at three credits per semester. For schools offering only one course in physical–chemical treatment of water and wastewater, this book gives the instructor the liberty of picking the particular topics required in a given curriculum design. After the student has been introduced to the preliminary topics of water and wastewater characterization, quantitation, and population projection, this book covers the unit operations and unit processes in the physical–chemical treatment of water and wastewater. The unit operations cover flow measurements and flow and quality equalization; pumping; screening, sedimentation, and flotation; mixing and floccu- lation; conventional filtration; advanced filtration and carbon adsorption; and aeration, absorption, and stripping. The unit processes cover water softening, water stabiliza- tion, coagulation, removal of iron and manganese, removal of phosphorus, removal of nitrogen, ion exchange, and disinfection. The requirements for the treatment of water and wastewater are driven by the Safe Drinking Water Act and Clean Water Act, which add more stringent require- ments from one amendment to the next. For example, the act relating to drinking water quality, known as the Interstate Quarantine Act of 1893, started with only the promulgation of a regulation prohibiting the use of the common cup. At present, the Safe Drinking Water Act requires the setting of drinking water regulations for some 83 contaminants. The act relating to water quality started with the prohibition of obstructions in harbors as embodied in the Rivers and Harbors Act of 1899. At present, the Clean Water Act requires that discharges into receiving streams meet water quality standards; in fact, regulations such as those in Maryland have an TX249_Frame_CFM.fm Page 5 Friday, June 14, 2002 4:51 PM © 2003 by A. P. Sincero and G. A. Sincero antidegradation policy. In recent years, problems with Cryptosporidium parvum and Giardia lamblia have come to the fore. Toxic substances are being produced by industries every day which could end up in the community water supply. These acts are technology forcing, which means that as we continue to discover more of the harmful effects of pollutants on public health and welfare and the environment, advanced technology will continue to be developed to meet the needs of treatment. The discipline of environmental engineering has mostly been based on empirical knowledge, and environmental engineering textbooks until recently have been writ- ten in a descriptive manner. In the past, the rule of thumb was all that was necessary. Meeting the above and similar challenges, however, would require more than just empirical knowledge and would require stepping up into the next level of sophisti- cation in treatment technology. For this reason, this textbook is not only descriptive but is also analytical in nature. It is hoped that sound concepts and principles will be added to the already existing large body of empirical knowledge in the discipline. These authors believe that achieving the next generation of treatment requirements would require the next level of sophistication in technology. To this end, a textbook written to address the issue would have to be analytical in nature, in addition to adequately describing the various unit operations and processes. This book teaches both principles and design. Principles are enunciated in the simplest way possible. Equations presented are first derived, except those that are obtained empirically. Statements such as “It can be shown…” are not used in this book. These authors believe in imparting the principles and concepts of the subject matter, which may not be done by using “it-can-be-shown” statements. At the end of each chapter, where appropriate, are numerous problems that can be worked out by the students and assigned as homework by the instructor. The question of determining the correct design flows needs to be addressed. Any unit can be designed once the flow has been determined, but how was the flow determined in the first place? Methods of determining the various design flows are discussed in this book. These methods include the determination of the average daily flow rate, maximum daily flow rate, peak hourly flow rate, minimum daily flow rate, minimum hourly flow rate, sustained high flow rate, and sustained low flow rate. What is really meant when a certain unit is said to be designed for the average flow or for the peak flow or for any flow? The answer to this question is not as easy as it may seem. This book uses the concept of the probability distribution to derive these flows. On the other hand, the loss through a filter bed may need to be determined or a deep-well pump may need to be specified. The quantity of sludge for disposal produced from a water softening process may also be calculated. This book uses fluid mechanics and chemistry without restraint to answer these design problems. Equivalents and equivalent mass are two troublesome and confusing concepts. If the chemistry and environmental engineering literature were reviewed, these subjects would be found to be not well explained. Equivalents and equivalent mass in a unified fashion are explained herein using the concept of the reference species. Throughout the unit processes section of this book, reference species as a method is applied. Related to equivalents and equivalent mass is the dilemma of expressing concentrations in terms of calcium carbonate. Why, for example, is the concentration TX249_Frame_CFM.fm Page 6 Friday, June 14, 2002 4:51 PM © 2003 by A. P. Sincero and G. A. Sincero of acidity expressed in terms of calcium carbonate when calcium carbonate is basic and acidity is acidic? This apparent contradiction is addressed in this book. As in any other textbook, some omissions and additions may have produced some error in this book. The authors would be very grateful if the reader would bring them to our attention. TX249_Frame_CFM.fm Page 7 Friday, June 14, 2002 4:51 PM © 2003 by A. P. Sincero and G. A. Sincero Acknowledgments First, I acknowledge Dr. Joseph L. Eckenrode, former Publisher, Environmental Science & Technology, Technomic Publishing Company, Inc. Dr. Eckenrode was very thorough in determining the quality, timeliness, and necessity of the manuscript. It was only when he was completely satisfied through the strict peer review process that he decided to negotiate for a contract to publish the book. Additionally, I acknowledge Brian Kenet and Sara Seltzer Kreisman at CRC Press. This book was written during my tenure at Morgan State University. I acknowl- edge the administrators of this fine institution, in particular, Dr. Earl S. Richardson, President; Dr. Clara I. Adams, Vice President for Academic Affairs; Dr. Eugene M DeLoatch, Dean of the School of Engineering; and Dr. Reginald L. Amory, Chairman of the Department of Civil Engineering. I make special mention of my colleague, Dr. Robert Johnson, who was the acting Chairman of the Department of Civil Engineering when I came on board. I also acknowledge my colleagues in the department: Dr. Donald Helm, Prof. A. Bert Davy, Dr. Indranil Goswami, Dr. Jiang Li, Dr. Iheanyi Eronini, Dr. Gbekeloluwa B. Oguntimein, Prof. Charles Oluokun, and Prof. Neal Willoughby. This acknowledgment would not be complete if I did not mention my advisor in doctoral studies and three of my former professors at the Asian Institute of Technology (A.I.T.) in Bangkok, Thailand. Dr. Bruce A. Bell was my advisor at the George Washington University where I earned my doctorate in Environmental–Civil Engineering. Dr. Roscoe F. Ward, Dr. Rolf T. Skrinde, and Prof. Mainwaring B. Pescod were my former professors at A.I.T., where I earned my Masters in Environmental– Civil Engineering. I acknowledge and thank my wife, Gregoria, for contributing Chapter 2 (Con- stituents of Water and Wastewater) and Chapter 7 (Conventional Filtration). I also acknowledge my son, Roscoe, for contributing Chapter 17 (Disinfection). Gregoria also contributed a chapter on solid waste management when I wrote my first book Environmental Engineering: A Design Approach . This book was published by Pren- tice Hall and is being adopted as a textbook by several universities here and abroad. This book has been recommended as a material for review in obtaining the Diplomate in Environmental Engineering from the Academy of Environmental Engineers. Lastly, I dedicate this book to members of my family: Gregoria, my wife; Roscoe and Arcadio Jr., my sons; the late Gaudiosa Pacquiao Sincero, my mother; Santiago Encarguiz Sincero, my father; and the late Aguido and the late Teodora Managase Alivio, my father-in-law and my mother-in-law, respectively. I also dedicate this book to my brother Meliton and to his wife Nena; to my sister Anelda and to her husband Isidro; to my other sister Feliza and to her husband Martin; and to my brother-in-law Col. Miguel M. Alivio, MD and to his wife Isabel. My thoughts also go to my other brothers-in-law: the late Tolentino and his late wife Mary, Maximino TX249_Frame_CFM.fm Page 9 Friday, June 14, 2002 4:51 PM © 2003 by A. P. Sincero and G. A. Sincero and his wife Juanita, Restituto and his wife Ignacia, the late Anselmo and his wife Silvina, and to my sisters-in-law: the late Basilides and her late husband Dr. Alfonso Madarang, Clarita and her late husband Elpidio Zamora, Luz and her husband Perpetuo Apale, and Estelita. Arcadio P. Sincero Morgan State University TX249_Frame_CFM.fm Page 10 Friday, June 14, 2002 4:51 PM © 2003 by A. P. Sincero and G. A. Sincero About the Authors Arcadio P. Sincero is Associate Professor of Civil Engineering at Morgan State University, Baltimore, MD. He was also a former professor at the Cebu Institute of Technology, Philippines. He holds a Bachelor’s degree in Chemical Engineering from the Cebu Institute of Technology, a Master’s degree in Environmental–Civil Engineering from the Asian Institute of Technology, Bangkok, and a Doctor of Science degree in Environmental–Civil Engineering from the George Washington University. He is a registered Professional Engineer in the Commonwealth of Penn- sylvania and in the State of Maryland and was a registered Professional Chemical Engineer in the Philippines. He is a member of the American Society of Civil Engi- neers, a member of the American Institute of Chemical Engineers, a member of the Water Environment Federation, a member of the American Association of University Professors, and a member of the American Society of Engineering Education. Dr. Sincero has a wide variety of practical experiences. He was a shift supervisor in a copper ore processing plant and a production foreman in a corn starch processing plant in the Philippines. He was CPM (Critical Path Method) Planner in a construc- tion management firm and Public Works Engineer in the City of Baltimore. In the State of Maryland, he was Public Health Engineer in the Bureau of Air Quality and Noise Control, Department of Health and Mental Hygiene; Water Resources Engi- neer in the Water Resources Administration, Department of Natural Resources; Water Resources Engineer in the Office of Environmental Programs, Department of Health and Mental Hygiene; Water Resources Engineer in the Water Management Admin- istration, Maryland Department of the Environment. For his positions with the State of Maryland, Dr. Sincero had been Chief of his divisions starting in 1978. His last position in the State was Chief of Permits Division of the Construction Grants and Permits Program, Water Management Administration, Maryland Department of the Environment. These practical experiences have allowed Dr. Sincero to gain a wide range of environmental engineering and regulatory experiences: air, water, solid waste, and environmental quality modeling. Gregoria A. Sincero is a senior level Water Resources Engineer at the Maryland Department of the Environment. She was also a former professor at the Cebu Institute of Technology, Philippines. She holds a Bachelor’s degree in Chemical Engineering from the Cebu Institute of Technology and a Master’s degree in Environmental–Civil Engineering from the Asian Institute of Technology, Bangkok, Thailand. She is a registered Professional Environmental Engineer in the Commonwealth of Pennsyl- vania and was a registered Professional Chemical Engineer in the Philippines. She is a member of the American Institute of Chemical Engineers. Mrs. Sincero has practical experiences both in engineering and in governmental regulations. She was Senior Chemist/Microbiologist in the Ashburton Filters of TX249_Frame_CFM.fm Page 11 Friday, June 14, 2002 4:51 PM © 2003 by A. P. Sincero and G. A. Sincero Baltimore City. In the State of Maryland, she was Water Resource Engineer in the Water Resources Administration, Department of Natural Resources and Water Resources Engineer in the Office of Environmental Programs, Department of Health and Mental Hygiene, before joining her present position in 1988 at MDE. At MDE, she is a senior project manager reviewing engineering plans and specifications and inspecting construction of refuse disposal facilities such as landfills, incinerators, transfer stations, and processing facilities. Also, she has experiences in modeling of surface waters, groundwaters, and air and statistical evaluation of groundwater and drinking water data using EPA’s Gritstat software. TX249_Frame_CFM.fm Page 12 Friday, June 14, 2002 4:51 PM © 2003 by A. P. Sincero and G. A. Sincero [...]... applied to water and wastewater in which no chemical changes occur We also define chemical treatment of water and wastewater as a process applied to water and wastewater in which chemical changes occur Gleaning from these definitions of physical and chemical treatments, in the overall sense, physical chemical treatment of water and wastewater is a process applied to water and wastewater in which chemical. .. Processes of Water and Wastewater Treatment Chapter 10 Water Softening 10. 1 10. 2 10. 3 10. 4 10. 5 10. 6 10. 7 Hard Waters Types of Hardness Plant Types for Hardness Removal The Equivalent CaCO3 Concentration Softening of Calcium Hardness Softening of Magnesium Hardness Lime–Soda Process 10. 7.1 Calculation of Stoichiometric Lime Required in the Lime–Soda Process 10. 7.2 Key to Understanding Subscripts 10. 7.3... Amendments Clean Water Act of 1977 Municipal Wastewater Treatment Construction Grants Amendments Water Quality Act of 1987 Public Law P L 8 0- 8 45 (June 30, 1948) P L 8 4-6 60 (July 9, 1956) P.L 8 7-8 8 P.L 8 9-2 34 P.L 8 9-7 53 P.L 9 1-2 24, Part I P.L 9 2-5 00 P.L 9 5-2 17 P.L 9 7-1 17 P.L 10 0- 4 control the continuing pollution of the environment In the United States, the passage of the Rivers and Harbors Act of 1899 may... Chemistry and Fluid Mechanics.” © 200 3 by A P Sincero and G A Sincero TX249_Frame_Intro Page 3 Friday, June 14, 200 2 1:45 PM Introduction This book is titled Physical Chemical Treatment of Water and Wastewater This chapter begins by defining wastewater and physical chemical treatment of water and wastewater and treats briefly the coverage It also addresses the unit operations and unit processes In addition,... Calculation of Stoichiometric Soda Ash Required 10. 7.4 Calculation of Solids Produced 10. 8 Order of Removal 10. 9 Role of CO2 in Removal 10. 10 Excess Lime Treatment and Optimum Operational pH 10. 11 Summary of Chemical Requirements and Solids Produced 10. 12 Sludge Volume Production 10. 13 Chemical Species in the Treated Water 10. 13.1 Limits of Technology 2+ 10. 13.2 Concentration of Ca 2+ 10. 13.3 Concentration of. .. is analytical and therefore requires the use of pertinent chemistry, mathematics, and fluid mechanics Relevant prerequisite topics are discussed in this part Part I, Characteristics of Water and Wastewater, covers the chapters on quantity and constituent physical and chemical characteristics of water and wastewater Part II, Unit Operations of Water and Wastewater Treatment, includes the chapters on flow... become a waste water On the other hand, to become a sewage, it is enough that water becomes polluted whether or not it had been used When one uses the word wastewater, however, the meaning of the two words is blended such that they now often mean the same thing Wastewater equals sewage PHYSICAL CHEMICAL TREATMENT OF WATER AND WASTEWATER What is physical chemical treatment of water and wastewater? The dictionary... June 14, 200 2 1:45 PM 6 Physical Chemical Treatment of Water and Wastewater COVERAGE This book is divided into four general parts and addresses important topics on the physical chemical treatment of water and wastewater The “first” part is titled Background Prerequisites Its contents are not really physical chemical treatment but just background knowledge to comfortably understand the method of approach... of water and wastewater treatment plants and the requirements of their levels of performance are mostly driven by government laws and regulations For example, the Clean Water Act mandates construction of wastewater treatment facilities that, at least, must produce the secondary level of treatment The Safe Water Drinking Water Act also requires performance of treatment plants that produce drinking water. .. Mg − 10. 13.4 Concentration of HCO 3 2− 10. 13.5 Concentration of CO 3 + 10. 13.6 Concentration of Na 10. 14 Relationships of the Fractional Removals 10. 15 Notes on Equivalent Masses 10. 16 Typical Design Parameters and Criteria 10. 17 Split Treatment 10. 18 Use of Alkalinity in Water Softening Calculations Glossary © 200 3 by A P Sincero and G A Sincero TX249_Frame_CFM.fm Page 20 Friday, June 14, 200 2 4:51 . PHYSICAL CHEMICAL TREATMENT OF WATER AND WASTEWATER CRC PRESS Boca Raton London New York Washington, D.C. PHYSICAL CHEMICAL TREATMENT OF WATER AND WASTEWATER Arcadio P. Sincero. Page 13 Friday, June 14, 200 2 4:51 PM © 200 3 by A. P. Sincero and G. A. Sincero PART I Characteristics of Water and Wastewater Chapter 1 Quantity of Water and Wastewater 1.1 Probability Distribution. and Wastewater Treatment Chapter 10 Water Softening 10. 1 Hard Waters 10. 2 Types of Hardness 10. 3 Plant Types for Hardness Removal 10. 4 The Equivalent CaCO 3 Concentration 10. 5 Softening