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In German Zinc and Lead Production FINAL DRAFT Report on Best Available Techniques (BAT) in German Zinc and Lead Production FINAL DRAFT Deutsch-Französisches Institut für Umweltforschung (DFIU) French-German Institute for Environmental Research University of Karlsruhe (TH) o. Prof. Dr. O. Rentz Dipl.-Ing. Stephan Hähre, Dr. Frank Schultmann Karlsruhe, February 1999 On behalf of the German Federal Environmental Agency, Berlin (UBA) in the frame of the Research Project 109 05 006 Contents 3 Contents PREFACE.............................................................................................................................................................13 1 GENERAL INFORMATION.......................................................................................................................... 15 1.1 PRODUCTION AND USE OF ZINC AND LEAD ................................................................................................... 15 1.1.1 Zinc ..................................................................................................................................................... 15 1.1.2 Lead .................................................................................................................................................... 16 1.2 FIRST INDICATION OF ENVIRONMENTAL CONCERNS REGARDING THE PRODUCTION OF ZINC AND LEAD ........ 19 1.2.1 Emissions into the atmosphere............................................................................................................ 19 1.2.2 Potential releases into water............................................................................................................... 21 1.2.3 Solid materials generated ................................................................................................................... 21 2 APPLIED PROCESS TECHNOLOGY AND ABATEMENT TECHNIQUES IN GERMAN ZINC AND LEAD PRODUCTION........................................................................................................................................ 23 2.1 INTRODUCTION AND SCOPE OF THE STUDY................................................................................................... 23 2.2 BASIC DESCRIPTION OF ZINC AND LEAD PRODUCTION .................................................................................. 24 2.2.1 Zinc production................................................................................................................................... 24 2.2.1.1 Hydrometallurgical zinc production ............................................................................................................. 25 2.2.1.1.1 General process description.................................................................................................................. 25 2.2.1.1.2 Main outputs and environmental concerns of the hydrometallurgical zinc production processes ........ 27 2.2.1.2 Pyrometallurgical zinc production ................................................................................................................ 29 2.2.1.2.1 Imperial Smelting Process .................................................................................................................... 29 2.2.1.2.2 Waelz kiln process................................................................................................................................ 34 2.2.1.2.3 Reduction in vertical retorts (New Jersey retort process route) ............................................................ 36 2.2.1.2.4 Fuming plant......................................................................................................................................... 37 2.2.1.2.5 Melting of metallic raw materials ......................................................................................................... 37 2.2.1.2.6 Refining of crude zinc .......................................................................................................................... 38 2.2.1.3 Zinc production plants in Germany............................................................................................................... 38 2.2.2 Lead production.................................................................................................................................. 41 2.2.2.1 Lead-containing raw materials...................................................................................................................... 41 2.2.2.2 Sinter plant - blast furnace route for lead production.................................................................................... 42 2.2.2.3 New direct smelting processes for lead production....................................................................................... 44 2.2.2.4 Lead production from secondary raw material.............................................................................................. 45 2.2.2.4.1 Preparation of battery and scrap materials............................................................................................ 46 2.2.2.4.2 Smelting furnaces ................................................................................................................................. 47 2.2.2.5 Lead refining................................................................................................................................................. 48 2.2.2.6 Main outputs and environmental concerns of lead production plants........................................................... 49 2.2.2.6.1 New direct smelting plants (QSL process, Sirosmelt Process) ............................................................. 50 2.2.2.6.2 Rotary and shaft furnace process plants using exclusively secondary raw materials ............................ 52 2.2.2.6.3 Refining of lead bullion from primary and secondary plants................................................................ 54 2.2.2.7 Lead production plants in Germany.............................................................................................................. 54 3 PROCESS TECHNOLOGY, ABATEMENT TECHNIQUES AND PRESENT CONSUMPTION/EMISSION LEVELS IN GERMAN ZINC AND LEAD PRODUCTION ...................... 57 3.1 ZINC PRODUCTION IN GERMANY.................................................................................................................. 57 3.1.1 Hydrometallurgical zinc production plants in Germany .................................................................... 57 3.1.1.1 Zinc electrolysis plant Z1.............................................................................................................................. 57 3.1.1.1.1 General information.............................................................................................................................. 57 3.1.1.1.2 Description of the main process units and environmental techniques .................................................. 59 3.1.1.1.3 Summarised data on outputs and environmental concerns ................................................................... 62 3.1.1.2 Zinc electrolysis plant Z2.............................................................................................................................. 63 4 Contents 3.1.1.2.1 General information.............................................................................................................................. 63 3.1.1.2.2 Description of the main process units and environmental techniques .................................................. 64 3.1.1.2.3 Summarised data on outputs and environmental concerns ................................................................... 69 3.1.2 Pyrometallurgical zinc production in Germany ................................................................................. 70 3.1.2.1 Imperial Smelting Process (ISP) plant Z3..................................................................................................... 70 3.1.2.1.1 General information.............................................................................................................................. 70 3.1.2.1.2 Description of the main process units and environmental techniques .................................................. 71 3.1.2.1.3 Summarised data on outputs and environmental concerns ................................................................... 76 3.1.2.2 Waelz plants operated in Germany (plants Z4, Z5, Z7) ................................................................................ 78 3.1.2.2.1 General information.............................................................................................................................. 78 3.1.2.2.2 Description of the main process units and environmental techniques .................................................. 81 3.1.2.2.3 Summarised data on outputs and environmental concerns ................................................................... 88 3.1.2.3 New-Jersey retort plant Z6............................................................................................................................ 89 3.1.2.3.1 General information.............................................................................................................................. 89 3.1.2.3.2 Description of the main process units and environmental techniques .................................................. 90 3.1.2.3.3 Summarised data on outputs and environmental concerns ................................................................... 92 3.1.2.4 Secondary zinc and zinc alloy production by remelting processes
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