Handbook of Chlor-Alkali Technology

Handbook of Chlor-Alkali Technology

Volume I: Fundamentals

Thomas F. O'Brien Independent Consultant Media, Pennsylvania

Tilak V. Bommaraju Independent Consultant Grand Island, New York

and

Fumio Hine Professor Emeritus Nagoya Institute of Technology Nagoya, Japan

~Springer

Library of Congress Cataloging-in-Publication Data

O'Brien, Thomas, 1934-Handbook of chlor-alkali technology/Thomas F. O'Brien, Tilak V. Bommaraju, Fumio Hine.

p. em. Includes bibliographical references and index.

1. Chlorine industry-Handbooks, manuals, etc. 2. Alkali industry and trade-Handbooks, manuals, etc. 3.

Electrochemistry, Industrial-Handbooks, manuals, etc. I. Bommaraju, Tilak V. II. Hine, Fumio. III. Title.

TP245.C5034 2005 2004051611

ISBN 978-0-306-48623-4 ISBN 978-0-306-48624-1 ( eBook)

©2005 Springer Science+ Business Media, Inc. All rights reserved. This work may not be translated or copied in whole or in part without the written permission of the publisher (Springer Science+ Business Media, Inc., 233 Spring Street, New York, NY 10013,

USA), except for brief excerpts in connection with reviews or scholarly analysis. Use in connection with any form of information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar

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proprietary rights.

9 8 7 6 5 4 3 2 1

springeronline.com

Foreword

It is surprising that we had to wait so long for a new book that gives a comprehensive treatment of chlor-alkali manufacturing technology. Technologists are largely still mak­ing do with the classical book edited by Sconce, but that is more than thirty years old. At the time of its publication, metal anodes were just beginning to appear, and ion-exchange membrane technology was confined to laboratories. The various encyclopedias of indus­trial technology have more up-to-date information, but they are necessarily limited in their scope. Schmittinger recently provided an excellent shorter treatment of the broad field of chlorine technology and applications. After discussing electrolysis and the prin­cipal types of cell, this, too, gives rather brief coverage to brine and product processing. It then follows on with descriptions of the major derivatives and direct uses of chlorine and a discussion of environmental issues.

The last feature named above has relieved the authors of this work of the obligation to cover applications in any detail. Instead, they provide a concentrated treatment of all aspects of technology and handling directly related to the products of electrolysis. It cov­ers the field from a history of the industry, through the fundamentals of thermodynamics and electrochemistry, to the treatment and disposal of the waste products of manufac­ture. Membrane cells are considered the state of the art, but the book does not ignore mercury and diaphragm cells. They are considered both from a historical perspective and as examples of current technology that is still evolving and improving. Dear to the heart of a director of Euro Chlor, the book also pays special attention to safe handling of the products, the obligations of Responsible Care®, and process safety management.

Other major topics include corrosion, membranes, electrolyzer design, brine pre­paration and treatment, and the design and operation of processing facilities. Perhaps uniquely, the book also includes a chapter on plant commissioning. The coverage of membranes is both fundamental and applied. The underlying transport processes and practical experience with existing types of membrane both are covered. The same is true of electrolyzer design. The book explores the basic electrode processes and the funda­mentals of current distribution in electrolyzers as well as the characteristics of the leading cell designs. The chapter on brine production and treatment first covers the sources of salt and the techniques used to prepare brine. It then explains the mechanisms by which brine impurities affect cell performance and outlines the processes by which they can be removed or controlled. While pointing out the lack of fundamental science in much of

v

vi FOREWORD

the process, it describes the various unit operations phenomenologically and discusses methods for sizing equipment and choosing materials of construction. The chapter on processing and handling of products is similarly comprehensive. Again, it is good to see that the authors have included a lengthy discussion of safe methods and facilities for the handling of the products, particularly liquid chlorine. While the discussion of the various processing steps includes the topic of process control, there is also a separate chapter on instrumentation which is more hardware oriented.

Other chapters deal with utility systems, cell room design and arrangement (with an emphasis on direct current supply), alternative processes for the production of either chlorine or caustic without the other, the production of hypochlorite, industrial hygiene, and speculations on future developments in technology. There is an Appendix with selected physical property data.

The authors individually have extensive experience in chlor-alkali technology but with diverse backgrounds and fields of specialization. This allows them to achieve both the breadth and the depth which are offered here.

The work is divided into five volumes, successively treating fundamentals, brine preparation and treatment, production technology, support systems such as utilities and instrumentation, and ancillary topics. Anyone with interest in the large field of chlor­alkali manufacture and distribution, and indeed in industrial electrochemistry in general, will find something useful here. The work is recommended to students; chlor-alkali tech­nologists; electrochemists; engineers; and producers, shippers, packagers, distributors, and consumers of chlorine, caustic soda, and caustic potash.

This book is thoroughly up to date and should become the standard reference in its field.

Barrie S. Gilliatt Executive Director

Euro Chlor March, 2004

Preface

Despite commercial setbacks in recent years, the production of chlorine and alkalis still is of enormous importance, and chlorine and caustic soda both are among the ten largest­volume chemical products in the world. The number of final end uses for the products of a chlor-alkali plant perhaps cannot be matched by any other single plant.

There is no comprehensive modern treatment of the chlor-alkali manufacturing process. The authors therefore saw a need for a book on the subject, focusing on chlorine and the alkali products themselves and providing full detail on basic electrochemistry, thermodynamics, and the processing and handling of raw materials and products. Product applications are not covered in any detail. The anticipated audience includes students, electrochemists, all engineers and scientists involved in chlor-alkali technology, and those with a lively interest in an important segment of industry.

This work is divided into five volumes. Volume I contains introductory and historical information, followed by the fundamentals of electrochemistry pertinent to chlor-alkali cells. The topics addressed include thermodynamics, kinetics of electrode reactions and electrocatalysis, experimental techniques, energy consumption and its components, and the basic aspects of mercury, diaphragm, and membrane cells. The importance of brine purification, the influence of brine impurities on electrolysis, and the meth­ods used for their removal are presented in Volume II. This volume also discusses the three major processes used for electrolysis (diaphragm, mercury, and membrane cells) and offers comparisons of the individual cell technologies employed. Volume III covers the practical aspects of plant engineering and operation. Subject matter includes cell room design and engineering and the processing of chlorine, hydrogen, and caustic soda or potash. There is also an extensive discussion of the safe stor­age and handling of the products. Volume IV deals with support systems such as plant utilities and instrumentation hardware and systems. It also contains a chapter dedicated to the commissioning and operation of plants, with an emphasis on mem­brane cell rooms. Volume V rounds out the presentation by treating a variety of topics. These include the fundamentals of corrosion; alternative processes for chlorine and caustic, each without the other as co-product; the manufacture of hypochlorites; general safety information (chemical hazards, industrial hygiene, safety programs, waste disposal or minimization); and possible future technological developments in the industry. An Appendix gives some of the physical and chemical properties of relevant materials.

Particularly in Volumes II and III, we present examples and discuss specifics of design. These are not to be taken as recommendations for any particular apparatus or

vii

viii PREFACE

technology. They are offered knowing that many alternatives exist in practice and that some readers may have their own preferred solutions. The authors feel that it is better to provide some practical feel for students and technologists who are unfamiliar with the subject than it is to hesitate because others approaches exist.

The authors expect that the typical reader will most frequently consult individual sections of most interest to him or her. Relatively few will read all five volumes consec­utively. We have therefore not hesitated to repeat basic information in order to provide quicker understanding of the subject at hand. There are also many cross-references between sections. These will assist the reader seeking broader coverage.

The book does not cover first aid or medical practice, nor does it supply complete details on safe handling of materials. Readers must refer to the literature, material safety data sheets, suppliers, and users of the various chemicals and equipment that are dis­cussed. While there are summaries of material specifications and suggested analytical schedules, there is likewise not a section on analytical procedures.

Safety is of primary importance in manufacture of chemicals. This book therefore makes frequenfreference to good practice in design, construction, and operation of chlor­alkali plants. The authors frequently refer to the subject and to various safety codes. We note here that no one code or set of practices may be best in all circumstances, and we take no position in this matter. When specific practices are discussed, it is not to say that they are the best or the only way. Rather, they are offered as possible approaches to specific problems when their inclusion seems to add value to the work. They are not all-inclusive, and as time goes on some will be supplanted by new codes and regulations.

Every effort has been made in preparing these volumes to provide information that is accurate and that will be useful to those involved in the chlor-alkali industry. The publisher and the authors jointly and severally make no guarantee and assume no liability in connection with any of the aforesaid information.

A NOTE ON USAGE

Generally, this book uses metric units, and the authors assume that technologists every­where are familiar and comfortable with these units. Strict SI practice is not observed, some published data being kept in units that may be more familiar to those in the chlor-alkali industry.

The language and spelling are intended to be standard American, and Amer­ican usage (barring the use of metric units) prevails. Thus, an "electrolyser" is an "electrolyzer."

ACKNOWLEDGEMENTS

The authors wish to acknowledge first the sizable contributions of Thomas A. Weedon, Jr., oflnformation Technology, Inc., and Dr. Gary M. Shannon, ofiNEOS Chlor Limited, principal authors, respectively, of Chapters 11 and 13. John M. Lucas made important contributions to the sections on electrical systems.

Euro Chlor and The Chlorine Institute generously made many of their publications available to the authors, and both organizations also granted permission to reproduce or

PREFACE ix

adapt a number of their illustrations. Dr. Barrie S. Gilliatt of Euro Chlor also contributed the Foreword. The authors are grateful to Steve Fitzgerald of Occidental Chemical Cor­poration and Dr. Kenzo Yamaguchi of Chlorine Engineers Corporation for providing us with their endorsements of the book.

Other contributors of material or technical assistance included:

Robert A. Arnold, James town Chemical Steve Brien, Mary Blackburn, Chemical Marketing Associates, Inc Dr. Chao-Peng Chen, Headway Technology- A TDK group company Thomas F. Florkiewicz, Donald J. Groszek, Richard L. Romine and Charles D. Schultz,

ELTECH Systems Corporation David Francis, DE NORA ELETTRODI S.p.A., Brent Hardman and members of staff, Powell Fabrication and Manufacturing, Inc. Glenn M. Hymel, Occidental Chemical Corporation Adam Jacobsen, Dorr-Oliver EIMCO Dr. James T. Keating, E.l. duPont de Nemours and Co, Inc. Charles J. Kotzo and Norbert Eckert, Chemetics Library, University of Dortmund Dr. Eric Linak, SRI Consulting Dr. Benno Ltike and K. Sambamurty, Uhde GmbH A. Stuart Middleton, Agra Simons C. E. "Skip" Niman, Cargill Salt Company Dr. S. Sarangapani, ICET, Inc. Roger E. Shamel, Consulting Resources Corporation Janet L. White, USFilter Corporation Dr. James R. Wilson, FMC Corporation Dr. Kenzo Yamaguchi, Chlorine Engineers Corporation

Reviewers of the material included:

Dr. Harry S. Burney Jr., Dow Chemical Corporation Prof. Brian E. Conway, University of Ottawa Dr. Yoshio Harada, Mitsubishi Heavy Industries, Ltd. Glenn M. Hymel, Occidental Chemical Corporation Jeffrey Jones, INEOS Chlor Limited Dr. James T. Keating, Jeffrey L. Jones, Robert D. Theobald, E.I. duPont de

Nemours and Co, Inc. Thomas A. Liederbach, Electrode Corporation Thomas J. Navin, Consultant Masao Ohkubo, Sumitomo Chemical Company Dr. Francis Otto, Jr., Alfa Laval Biokinetics Richard L. Romine, Dr. Kenneth L. Hardee, ELTECH Systems Corporation Philip H. Sears, Chlorine Solutions LLC (ex Vulcan Chemical) Dr. Ian F. White, Advanced Optimax Consulting, Ltd. Dr. Harry C. Williford, Catalytic, Inc. Dr. Kenzo Yamaguchi, Chlorine Engineers Corporation

X PREFACE

The authors would like to thank Mike Smith for the excellent graphics and his patience in putting up with the constant changes. Finally, Tilak V. Bommaraju would like to acknowledge his wife, Savithri and his daughters, Sudha and Uma for their encouragement during the course of this effort, with special thanks to his daughter, Sudha, for her help in typing from hand written drafts and page-proofing.

Contents

Volume 1: Fundamentals

Chapter 1. Introduction

1.1. Purpose and Scope of the Book 1.2. Origin of the Importance of Chlorine and Caustic 1.3. End Uses of Chlorine

1.3.1. Organic Chemicals 1.3.2. Inorganic Chemicals

1.4. End Uses of Sodium Hydroxide 1.4.1. Organic Chemicals 1.4.2. Inorganic Chemicals

1.5. End Uses of Potassium Hydroxide References

Chapter 2. History of the Chlor-Alkali Industry

2.1. Diaphragm-Cell Technology Development 2.1.1. Vertical Diaphragm Cells 2.1.2. Developments in Anodes and Diaphragms 2.1.3. Diaphragm-Cell Technologies 2.1.4. Bipolar Diaphragm Cells

2.2. Mercury-Cell Technology 2.3. Membrane-Cell Technology 2.4. Caustic Soda

2.4.1. Lime Soda Process 2.4.2. Electrolytic Process

2.5. Future Developments References

Chapter 3. Overview ofthe Chlor-Alkali Industry

3 .1. Introduction 3.2. Overall Process

xi

1 2 4 4

11 11 14 15 15 16

17

18 22 24 26 27 28 31 34 35 35 35 35

37

37 37

xii

3.2.1. Electrolyzers 3.2.2. Chlorine Processing 3.2.3. Hydrogen Processing 3.2.4. Caustic Soda Process 3.2.5. Brine Process

3.3. Growth of the Chlor-Alkali Industry 3.3.1. World 3.3.2. United States 3.3.3. Chlor-Alkali Industry in Canada 3.3.4. Chlor-Alkali Industry in Mexico and Brazil 3.3.5. Chlor-Alkali Industry in Western Europe 3.3.6. Chlor-Alkali Industry in Eastern Europe 3.3.7. Chlor-Alkali Industry in The Middle East 3.3.8. Chlor-Alkali Industry in Japan 3.3.9. Chlor-Alkali Industry in Korea, Taiwan, China, and India 3.3.10. Chlorine and Caustic Prices

3.4. Environmental Considerations Affecting the Growth of the Chlor-Alkali Industry 3.4.1. Organic Chemicals 3.4.2. Inorganic Chemicals and Direct Application

CONTENTS

37 40 40 41 43 46 47 52 59 60 60 64 64 64 65 65

66 67 72

References 7 4

Chapter4. Chemistry and Electrochemistry of the Chlor-Alkali Process 75

4.1. Thermodynamics 4.1.1. Free Energy and Its Significance 4.1.2. Nernst Equation 4.1.3. Reversible Electrode Potentials 4.1.4. Thermodynamic Decomposition Voltage 4.1.5. Galvanic vs Electrolytic Cells 4.1.6. Measurement of Standard Single Electrode Reduction Potentials 4.1. 7. Standard Reference Electrodes

References 4.2. Kinetics

4.2.1. 4.2.2. 4.2.3. 4.2.4. 4.2.5.

References

Introduction Electrochemical Rate Equation Tafel Slope and Exchange Current Density Rate Equation Under Mass Transfer Control Electrocatalysis

4.3. Electrochemical Techniques 4.3.1. Introduction 4.3.2. Steady-State Techniques 4.3.3. Non-Steady-State Techniques 4.3.4. Supporting Techniques 4.3.5. Conductivity Measurements

References

75 75 78 81 89 89 90 92 94 95 95 96 99

104 107 125 127 127 128 142 150 150 160

CONTENTS

4.4. Energy Consumption

4.4.1. Faraday's Law

4.4.2. Energy Consumption Calculations

4.4.3. Current Efficiency

4.4.4. Cell Voltage and Its Components

References

4.5. Anodes

xiii

163

163

165

167

195

210

211

4.5.1. Introduction 211

4.5.2. Electrode Preparation 212

4.5.3. Other Patented Anode Compositions 213

4.5.4. Physical Characteristics and Morphology of Ru02 + Ti02-Based Electrodes 214

4.5.5. Electrochemical Behavior of Ru02 + Ti02-Based Coatings 217

4.5.6. Cell Performance Characteristics with RuOz + Ti02-Based Anodes 224

4.5.7. Anode Failure Mechanisms 224

4.5.8. Anode Structures 232

4.5.9. Anode Costs and Manufacturers 234

4.5.10. Alternate Anode Compositions

References

4.6. Cathodes

4.6.1. Introduction

4.6.2. Criteria for Low Overvoltage Hydrogen Cathode

4.6.3. Methods Employed to Realize High Surface Area

4.6.4. Cathode Materials and Compositions

4.6.5. HER Mechanisms on Low Overvoltage Cathodes

4.6.6. Cathode Deactivation

4.6.7. Current Status References

4. 7. Diaphragms

4. 7 .1. Introduction

4.7.2. Asbestos Diaphragms

4.7.3. Transport Characteristics of Diaphragms

4.7.4. Mass Transfer through Diaphragms

4.7.5. Modified Asbestos Diaphragms

4.7.6. Non-Asbestos Diaphragms

4. 7. 7. Diaphragm Deposition

4.7.8. Effect of Shutdowns on the Performance of Diaphragms

References

4.8. Ion-Exchange Membranes

4.8.1. Introduction

237

238

241

241

244

251

252

261

263

265 266

271

271

272

274

279

290

293

295

300

303

306

306

4.8.2. Chemical Structure and Synthesis of Perftuorinated Membranes 306

xiv

4.8.3. Physicochemical Properties 4.8.4. Transport Characteristics 4.8.5. Performance Characteristics of Membranes 4.8.6. Membrane Damage 4.8.7. Brine Purity Specifications 4.8.8. High Performance Membranes-New Developments

References 4.9. Amalgam Decomposition

4.9.1. Introduction 4.9.2. Design Aspects of the Amalgam Decomposer 4.9.3. Graphite Packings

References

Volume II: Brine Treatment and Cell Operation

Chapter 5. Chlor-Alkali Technologies

5 .1. Introduction 5.2. Cell Types-Bipolar and Monopolar

5 .2.1. Origin of Parasitic Currents 5.2.2. Modeling 5.2.3. Experimental Determination of Leakage Currents 5.2.4. Minimization of Leakage Currents

5.3. Mercury-Cell Technologies 5.3.1. DeNora Mercury Cells 5.3.2. Uhde Mercury Cells 5.3.3. Krebskosmo Mercury Cells 5.3.4. Olin Mercury Cells 5.3.5. Amalgam Decomposers

5.4. Diaphragm-Cell Technologies 5.4.1. Bipolar Filter-Press Cells 5.4.2. Vertical Diaphragm Cells

5.5. Membrane-Cell Technologies 5.5.1. Guidelines for Choosing Cell Technologies 5.5.2. Electrolyzer Technologies: General 5.5.3. Commercial Electrolyzers

References

Chapter 6. Process Overview

6.1. General Introduction 6.2. Brine Preparation and Treatment 6.3. Electrolysis

CONTENTS

310 323 341 350 352 355 370 375 375 378 386 386

387

387 388 391 394 397 398 398 400 402 403 403 404 405 405 408 413 413 426 426 439

443

443 443 446

CONTENTS

6.4. Product Recovery 6.4.1. Chlorine 6.4.2. Hydrogen 6.4.3. Caustic

6.5. Mass Balances 6.6. Process Design

6.6.1. Cell Room Operating Variables 6.6.2. Process Control 6.6.3. Cell-to-Cell Variation

References

Chapter7. Brine Preparation and Treatment

7.1. Sources of Salt 7.1.1. General 7.1.2. Rock Salt 7.1.3. Solar Salt 7.1.4. Other Sources 7.1.5. Refining of Salt 7.1.6. Potassium Chloride 7.1.7. Storage of Salt

7.2. Preparation of Brine 7.2.1. Salt Handling 7.2.2. Salt Dissolving

7.3. Brine Storage and Transfer 7.3.1. Storage of Brine 7.3.2. Transfer of Brine

7.4. The Role of Brine Purification 7.4.1. Composition of Salts and Brines 7.4.2. Effects of Brine Impurities

7.5. The Brine Treatment Process 7.5.1. Brine Specifications and Treatment Techniques 7.5.2. Chemical Treatment 7.5.3. Clarification and Thickening 7.5.4. Filtration 7.5.5. Ion Exchange 7.5.6. Acidification of Feed Brine 7.5.7. Control of Sulfates 7.5.8. Control of Other Brine Impurities 7.5.9. Removal of Dissolved Chlorine and Chlorate

References

Volume III: Facility Design and Product Handling

ChapterS. Cell-Room Design

8.1. Introduction

XV

449 449 451 451 453 458 458 459 463 464

465

465 465 466 469 475 478 487 492 495 495 509 525 525 527 529 529 529 543 543 545 564 587 606 626 634 649 665 696

705

705

xvi CONTENTS

8.2. Building Considerations 706 8.2.1. Outdoor vs Indoor Installation 706 8.2.2. Electrolyzer and Building Arrangements 706 8.2.3. Building Ventilation 712

8.3. Electrical Systems 713 8.3.1. Supply of Direct Current 713 8.3.2. Electrical Supply Efficiency 736

8.4. Cell-Room Auxiliaries 745 8.4.1. Piping 745 8.4.2. Cell-Room Process Control 749 8.4.3. Cell Renewal Activities 753

8.5. Cell-Room Hazards 755 8.5.1. Electrical Hazards 755 8.5.2. Chemical and Explosion Hazards 761

References 762

Chapter9. Product Handling 765

9.1. Chlorine 765 9.1.1. Introduction 765 9.1.2. Materials of Construction 767 9.1.3. Cooling 771 9.1.4. Drying 792 9.1.5. Mist Elimination 805 9.1.6. Compression 807 9.1.7. Liquefaction 829 9.1.8. Storage and Handling of Chlorine 847 9.1.9. Handling of Liquefaction Tail Gas 884 9.1.10. Safety Devices 895 9.1.11. Explosion Hazards 909 9.1.12. Evacuation and Sniff Systems 925

9.2. Hydrogen 927 9.2.1. Cathode Construction 927 9.2.2. Uses of Hydrogen 928 9.2.3. Compression 934 9.2.4. Cooling 936 9.2.5. Purification of Hydrogen 939 9.2.6. Hazards 943

9.3. Caustic Soda and Potash 944 9.3.1. Products of the Various Cells 944 9.3.2. Processing of Caustic Liquors 947 9.3.3. Evaporation 968 9.3.4. Purification of Caustic 983 9.3.5. Solid Caustic 987 9.3.6. Caustic Product Handling 990

9.4. Byproduct Utilization 995 9.4.1. Evaporator Salt 995 9.4.2. Sodium Sulfate 997

CONTENTS

9.4.3. 9.4.4.

References

Amalgam Calcium Carbonate

Volume IV: Plant Commissioning and Support Systems

Chapter 10. Chemical Engineering Principles

10.1. Introduction 10.2. Material and Energy Balance

10.2.1. Thermodynamics I 0.2.2. Energy Balance in Electrochemical Processes

References 10.3. Current Distribution

1 0.3.1. Primary Current Distribution 10.3.2. Secondary Current Distribution 10.3.3. Tertiary Current Distribution 10.3.4. Numerical Methods 10.3.5. Some Examples

References 10.4. Fluid Processing

1 0.4.1. Fluid Dynamics 10.4.2. Removal of Solids 10.4.3. Compression and Liquefaction

References 10.5. Transport Operations

I 0.5.1. Heat Transfer I 0.5.2. Gas Absorption I 0.5.3. Adsorption and Ion Exchange I 0.5.4. Distillation

References

Chapter 11. Instrumentation and Control Systems

11.1. Introduction 1 I. 1.1. General 11.1.2. Design Coordination 11.1.3. Control System Selection

11.2. Brine Systems 11.2.1. Modes of Control 11.2.2. Membrane-Cell Brine Systems

11.3. Chlorine Systems 11.3.1. Background 11.3.2. Operating Systems

xvii

1003 1006 1006

1013

1013 1013 1014 1023 1031 1031 1031 1036 1039 1040 1040 1047 1048 1048 1057 1058 1062 1062 1063 1067 1074 1081 1087

1089

1089 1089 1091 1092 1092 1092 1093 1113 1113 1113

xviii

11.4. Hydrogen Systems 11.4.1. Introduction 11.4.2. Membrane- and Mercury-Cell Hydrogen Systems 11.4.3. Diaphragm-Cell Hydrogen Systems

11.5. Caustic Systems 11.5.1. Mercury-Cell Caustic Systems 11.5.2. Diaphragm-Cell Caustic Systems 11.5 .3. Membrane-Cell Caustic Systems

11.6. Caustic Evaporation Systems 11.6.1. Membrane-Cell Caustic Evaporation 11.6.2. Diaphragm-Cell Caustic Evaporation

References

Chapter 12. Utilities

12.1. Introduction 12.2. Electricity 12.3. Steam and Condensate

12.3.1. Steam Systems 12.3.2. Steam Condensate 12.3.3. Cogeneration Systems

12.4. Water Systems 12.4.1. Sources of Water and General Plant Use 12.4.2. Water as Heat Sink 12.4.3. Purified Water

12.5. Air Systems 12.5.1. Plant or Utility Air 12.5.2. Purified Air 12.5.3. Nitrogen 12.5.4. Backup Systems

12.6. Vacuum Systems 12.6.1. Sources of Vacuum 12.6.2. Vapor Condensers 12.6.3. Process Control

12.7. Utility Piping and Connections 12.7.1. Utility Piping and Headers 12.7.2. Utility-Process Connections

References

Chapter 13. Plant Commissioning and Operation

13.1. Introduction 13.2. Commissioning Organization and Planning

13.2.1. Systems Approach and Personnel 13.2.2. Planning

CONTENTS

1134 1134 1135 1147 1149 1149 1151 1152 1159 1159 1166 1168

1169

1169 1170 1171 1171 1173 1174 1177 1177 1180 1191 1196 1196 1198 1201 1201 1201 1202 1208 1210 1211 1211 1212 1216

1217

1217 1218 1218 1219

CONTENTS xix

13.3. Training 1220 13.4. Documentation 1223

13.4.1. Operating Manual 1223 13.4.2. Maintenance Manual 1225 13.4.3. Analytical Manual 1225

13.5. General Precommissioning 1226 13.5.1. Flushing and Cleaning 1226 13.5.2. Pressure Testing 1227 13.5.3. Punch Lists 1229 13.5.4. Control Systems and Equipment Packages 1230

13.6. System Commissioning 1231 13.6.1. Commissioning Procedures 1232 13.6.2. General Notes on Commissioning of Instrumentation 1232 13.6.3. Brine System 1234 13.6.4. Catholyte System 1237 13.6.5. Chlorine System 1238 13.6.6. Hydrogen System 1243 13.6.7. Caustic Evaporation System 1244 13.6.8. Rectifier/Transformers 1247

13.7. Electrolyzer Assembly, Testing, and Installation 1247 13.7.1. Membrane Handling 1247 13.7.2. Membrane Installation 1249 13.7.3. Electrolyzer Testing 1253 13.7.4. Storage and Berthing 1254 13.7.5. Record Keeping 1255

13.8. Plant Operation 1256 13.8.1. Initial Plant Startup 1256 13.8.2. Normal Cell Room Operation 1261 13.8.3. Electrolyzer Shutdowns 1264 13.8.4. Normal Electrolyzer Startup 1267

13.9. Plant Performance Testing 1268 13.10. Cell Room Operating Specifications 1271

13.10.1. Product Quality 1271 13.10.2. Electrolyzer Voltage and Energy Consumption 1272 13.10.3. Membrane Operating Conditions 1273 13.10.4. Cell Room Material Specifications 1276 13.10.5. Sources and Effects of Impurities 1277 13.10.6. Cell Operating Conditions 1283

13.11. Routine Monitoring and Analysis 1286 13.11.1. Recording of Operating Parameters 1286 13.11.2. Analytical Program 1287 13.11.3. Current Efficiency Determination 1288 13.11.4. Voltage Monitoring 1290

13.12. Decommissioning of Mercury-Cell Plants 1290 References 1293

XX

Volume V: Corrosion, Environmental Issues, and Future Development

Chapter14. Corrosion

14.1. Introduction 14.2. Origin of Corrosion

14.2.1. Free Energy Considerations 14.2.2. Kinetics 14.2.3. Corrosion Prevention 14.2.4. Corrosion Rates

14.3. Manifestations of Corrosion 14.3.1. Uniform or General Corrosion 14.3.2. Galvanic or "Two-Metal" Corrosion 14.3.3. Crevice Corrosion 14.3.4. Pitting Corrosion 14.3.5. Intergranular Corrosion 14.3.6. Selective Leaching or Dealloying 14.3.7. Erosion Corrosion 14.3.8. Stress Corrosion 14.3.9. Corrosion Fatigue 14.3.10. High-Temperature Corrosion 14.3.11. Failure of Nonmetallic Materials

14.4. Material Selection 14.5. Corrosion In Chlor-Alkali Operations

14.5.1. General Aspects 14.5.2. Materials of Construction in Chlor-Alkali

Operation References

Chapter15. Alternative Processes

15.1. Introduction 15.2. Production of Chlorine without Caustic

15.2.1. Oxidation Processes 15.2.2. Electrochemical Methods for Producing Chlorine

15.3. Production of Hypochlorite 15.3.1. Electrochemical Production of Hypochlorite 15.3.2. Chemical Production of Hypochlorite 15.3.3. Miscellaneous Applications 15.3.4. Calcium Hypochlorite

15.4. Production of Caustic without Chlorine 15.4.1. Causticization of Soda Ash 15.4.2. Salt Splitting by Ion Exchange 15.4.3. Electrochemical Methods

References

CONTENTS

1295

1295 1297 1297 1303 1308 1311 1312 1313 1313 1314 1317 1318 1319 1319 1320 1323 1323 1325 1325 1328 1328

1328 1347

1349

1349 1351 1351 1361 1372 1373 1378 1388 1389 1389 1389 1392 1393 1396

CONTENTS xxi

Chapter16. Environmental Safety and Industrial Hygiene 1401

16.1. General Introduction 1401 16.2. Materials Hazards 1402

16.2.1. Chlorine and Hypochlorites 1403 16.2.2. Caustic Soda and Potash 1407 16.2.3. Hydrogen 1407 16.2.4. Hydrochloric Acid 1407 16.2.5. Sulfuric Acid 1408 16.2.6. Mercury 1408 16.2.7. Asbestos 1413 16.2.8. Nitrogen Trichloride 1415 16.2.9. Other Materials 1416

16.3. Process Hazards 1419 16.4. Prevention and Mitigation 1421

16.4.1. Safety Equipment 1421 16.4.2. Safety-Oriented Programs 1422 16.4.3. Mitigation of Effects of Release of Chlorine 1438

16.5. Waste Minimization and Disposal 1445 16.5.1. Solids 1445 16.5.2. Liquids 1448 16.5.3. Vapors and Gases 1451 16.5.4. Retired Brine Caverns 1452 16.5.5. Mercury-Containing Wastes 1452

References 1459

Chapter17. Future Developments 1463

17.1. Introduction 1463 17.2. Cell Operation 1464

17.2.1. Increased Current Density 1464 17.2.2. Depolarized Cathodes and Fuel Cells 1466 17.2.3. Membranes 1473

17.3. Auxiliary Operations 1474 17.3.1. Back-Pulse Filtration 1475 17.3.2. DC Power Supply 1477

17.4. Chlorine Processing 1478 17.4.1. Integrated Production of Ethylene Dichloride 1478 17.4.2. Chlorine Recovery 1478

17.5. Speculations 1480 17.5.1. Improved Electrodes 1480 17.5.2. Operation under Pressure 1480

References 1487

Appendix 1491

A. Universal Constants 1491

xxii CONTENTS

B. Conversion Factors 1491 c. Dimensionless Groups 1495 D. Nomenclature in Appendix C 1496 E. Correlations 1496 F. Sodium Chloride 1502 G. Potassium Chloride 1510 H. Sodium Hydroxide 1516 I. Potassium Hydroxide 1525 J. Chlorine 1532 K. Hydrogen 1539 L. Sulfuric Acid 1543 M. Hydrochloric Acid 1546 N. NaOH + NaCl Mixtures 1552 0. Bleach 1552 P. Sodium Carbonate 1553 Q. Water 1554 R. Miscellaneous 1556

Index 1561