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View Table of Contents (PDF) PROCESS ECONOMICS PROGRAM SRI INTERNATIONAL Menlo Park, California 94025 Abstract Proceee Economic Program Report No. 61 D CHLORINE (June 1992) Chloralkali producers around the world - in the major industrialized countries in particular - are pondering the balance between sagging demand for chlorine and strong demand for caustic soda. The former is caused by increasing environmental pressure in the following major sectors: l Dioxin generated during pulp bleaching with chlorine has forced the pulp and paper indus- try to switch from chemical bleaching to chemi-thermal mechanical bleaching, replacing chlorine with hydrogen peroxide. l Serious depletion of ozone layers has caused the major industrialized countries to totally phase out CFC production by 1995-l 996,4 to 5 years ahead of the deadline set by the 1990 internationally approved Montreal Protocol. l Laws in Western Europe have been proposed to restrict the use of PVC for food and non- food packaging. This report, a supplement to PEP Report 61 C issued in December 1962, presents a compre- hensive review of technology and economics for the production of primary chlorine by electrolysis of brine in the membrane cell, diaphragm cell, or mercury cell processes, and production of secondary chlorine by catalytic oxidation as well as electrolysis of HCI. Also presented are preliminary eco- nomicsfor process conversion and retrofit from either mercury cells or diaphragm cells to membrane cells. PEP’92 YRC Report No. 61 D CHLORINE SUPPLEMENT D by YU-REN CHIN with contributions by CHEE-HORNG CHANG MING-KUNG SHEN June 1992 A private report by the Menlo Park, California 94025 For detailedmarketing data and information, the reader is referred to one of the SRI programs specializing in marketing research. The CHEMCAL ECONOMCS HANDBOOK Program cwers most major chemicals and chemical products produced in the United States and the WORLD PETROC#EM/CALS Program covers major hydrocarbons and their derivativeson a worldwide basis. In addition, the SRI D/RECTORY OF CHEMICAL PRODUCERS services provide detailed lists of chemical producers by company, product, and plant for the United States, Western Europe, Canada, and East Asia. 1 INTRODUCTION........................................................ l-l 2 SUMMARY ............................................................ 2-l GENERAL ASPECTS .................................................... 2-l CHLORINE MANUFACTURING TECHNOLOGY. .............................. 2-l Technology For Primary Chlorine. ...................................... 2-l Membrane Cell T-logy ....................................... 2-2 Diaphragm Cell Technology ....................................... 2-3 Mercury Cell Technology .......................................... 2-3 Conversion and Retroflt ........................................... 2-4 Technology For Secondary Chlorine .................................... 2-4 ECONOMICS OF CHLORINE PRODUCTlON ................................ 2-5 Primary Chlorine Production .......................................... 2-5 Secondary Chlorine Production ........................................ 2-6 3 INDUSTRYSTATUS ..................................................... 3-l CHLORINESUPPLY .................................................... 3-1 Chloralkali Production in the United States .............................. 3-2 Chloralkall Production in Western Europe ............................... 3-3 Chloralkall Production in Japan ....................................... 3-3 Chloralkali Production in Canada ...................................... 3-3 Chloralkali Production In Other Regions ................................. 3-3 CHLORINE DEMAND ................................................... 3-32 Chloralkali Demand in the United States ................................ 3-32 Chloralkali Demand in Western Europe ................................. 3-32 Chloralkall Demand in Japan ......................................... 3-33 Chloralkali Demand in Canada ........................................ 3-33 Chloralkali Demand in Other Regions ................................... 3-34 4 REVIEW OF TECHNOLOGY FOR ELECTROLYSIS OF SALT ................... 4-l CHEMISTRY ........................................................... 4-l QUALITYOFBRINE .................................................... 4-3 - iii - CONTENTS(Continued) 4 REVIEWOF TECHNOLOGYFOR ELECTROLYSISOF SALT(Concluded) ELECTRODES ......................................................... 4-4 Anodes ........................................................... 4-4 Cathodes ......................................................... 4-5 DIAPHRAGM PROCESSES .............................................. 4-8 Diaphragms ....................................................... 4-7 Diaphragm Electrolyzer .............................................. 4-7 MEMBRANE PROCESSES ............................................... 4-8 Composition of Membrane ........................................... 4-8 Mamfaclureof Membranes ........................................... 4-9 Properties and Performance of Membranes .............................. 4-10 CommercialMembranes ............................................. 4-11 Struclure of Membrane Electrolyzers ................................... 4-12 PowerConsumption ................................................. 4-17 Commercial Membrane Electrolyzers ................................... 4-28 OPERARON OF MEMBRANE ELECTROLYZERS ............................. 4-25 MERCURY CELL PROCESSES ........................................... 4-28 Commercial Mercury Electrolyzers ..................................... 4-28 CAUSTIC SODA ....................................................... 4-27 CHLORINE ............................................................ 4-28 SMALL ELECTROLYTICCELLS ........................................... 4-28 OTHER ELECTROLYTICCELLS ........................................... 4-28 6 ECONOMICS OF ELECTROLYTlCPROCESSES FOR CHLORINE.............. 5-l MEMBRANE CELL PROCESS ............................................ 5-l Process Description ................................................. 5-2 BrInePurification ................................................ 5-2 Electrolysis ..................................................... 5-4 Caustic Soda Concentration ....................................... 5-4 ChlorIneRecovery ............................................... 5-5 Hydrogen Chloride Formation ...................................... 5-5 Hydrogen Recwery .............................................. 5-5 -iv- CONTENTS(Continued) 5 ECONOMICS OF ELECTROL~C PROCESSESFOR CHLORINE(Concluded) Process Discussion ................................................. 5-13 CostEstimates ..................................................... 5-14 DIAPHRAGM CELL PROCESS ............................................ 5-24 Cost Estimates ..................................................... 5-24 MERCURY CELL PROCESS .............................................. 5-33 CostEstimates.. ................................................... 5-33 ECONOMICCOMPARISON .............................................. 5-42 6 CONVERSIONOR RETROFITOF ELECTROLYTICCELLS . 6-l REViRN OF PATENTS ................................................... 6-2 EFFECTS OF CONVERSION OR REiROFiT ON PLANT OPERATIONS ........... 6-3 Brine Purification ................................................... 6-4 Rectifier/Transformer System .......................................... 6-4 CellRoom ......................................................... 6-4 CirculationSystem .................................................. 6-5 Dechlorination of Anolyte ............................................. 6-5 Caustic Concentration ............................................... 6-5 Chlorine and Hydrogen Recovery ...................................... 6-6 Off-siteStorage .................................................... 6-6 ECONOMICS OF PROCESS CONVERSION, RETROFTT,OR COMBINATIONS ..... 6-6 Case 1: Conversion of Diaphragm Cells to Membrane Cells ................ 6-6 ProcessConversion ............................................. 6-7 EconomicsofConversion ......................................... 6-6 Case 2: Retrofitting a Diaphragm Cell Process to a Membrane Cell Process ... 6-13 ProcessRetrofit ................................................. 6-13 Economicsof Retrofit ............................................ 6-13 Case 3: Conversion of Mercury Cells to Membrane Cells ................... 6-20 ProcessConversion ............................................. 6-20 - Economicsof Conversion ......................................... 6-20 Case 4: Combination of Diaphragm Cells with Membrane Cells ............. 6-26 Diaphragm/Membrane Combination System .......................... 6-26 0 Economics of Diaphragm/Membrane Combination System .............. 6-27 -V- CONTENTS(Concluded) 6 CONVERSIONOR RETROFITOF ELECTROLYnCCELL (Concluded) Case 5: Combination of Mercury Cdls with Membrane Cells ................ 6-32 Mercury/Membrane Combination System ............................ 6-32 Economics of Mercury/Membrane Combination System ................ 6-33 7 CHLORINE RECOVERYFROM HYDROGENCHmRIDE , . 7-l OXYCHLORINATION . 7-l HCI ELECTROLYSIS . 7-l CATALynC OXlDATtON OF HCI . 7-4 8 ECONOMICS OF PROCESSES FOR RECOVERYOF CHU)RINE FROM HCI .... 6-l CHUJRINE FROM HCI BY OXlDATtON WlTH A CHROMIUM OXIDE CATALYST ... 6-l Process Description ................................................... 6-l Hydrogen Chloride Purification and Oxidation
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