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International Nuclear Fuel Cycle Evaluation Working Group 1 Sub Group D Heavy Water Availability

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International Nuclear Fuel Cycle Evaluation Working Group 1 Sub Group D Heavy Water Availability INFCE International Nuclear Fuel INFCE/DEP/WC.1/9 Cycle Evaluation TOPICAL AND, WORKING PAPERS ON HEAVY WATER msqUTHEWENTS AND AVAILABILITY INPCB/DBP/WGI/9 INFCE WORKING GROUP 1 TOPICAL AMD WORKING PAPERS ON HEAVY MATER REQUIREMENTS AND AVAILABILITY Working Group 1, through Sub-Group ID, collected topical papers and prepared working papers related to heavy water renuirements, production technology and availability of production capacity* These papers were then used by Sub-Group ID to prepare a report on the subject cf heavy water requirements and availabilty. The final report of Sub-Group ID, together with the background papers used in its preparation, have been collected and consolidated into this single document, for the convenience of the participants in INFCE and those seeking background information to the Working Group 1 Pinal Report* The documents included in this document are listed below* 1* Heavy Water Requirements and Availability, Co-Chairmen/WGl/32( D) Final Report from Sub-Group ID, September 1979* 2. Technological Infra-Structure for Heavy Co-Chairmen /WGl/ll(D) Water Plants, 16 October 1978. 3* Considerations Governing Heavy Water Plant Co-Chairmen /WGl/l9(D) Siting, June 1978. 4* Hydrogen and Methane Availability, Co-Chai rmen/WGl/44(D) September 1978. 5« Economics of Heavy Water Production, Co-Chairmen /WGl/52(D) 16 October 1973. 6* Processes for Heavy Water Production, Co-Chai rmen/WGl/56(D) 16 October 1978. 7. Monothermal, Water-Fed Heavy Water Process Co-Chairmen/WGl/71(D) Based on the Ammonia/Hydrogen Isotopic Exchange, April 1979» 8* Production Strategies to Meet Demand Co-Chairmen/wai/7?(D) Projections, 1979* 9* Further Note on Hydrogen Availability, Co-Chairmen/WGl/lJ(D) 19 October 1978. 10. Deuterium Sources, Production Technologies, Co-Chairmen/WGl/li(D) Technical Infrastructure Required and Siting Considerations (for Heavy Water Production), March 1979. 11. The"Independent UHDE Heavy Water Process, Co-Chai rmen/WOl/76(D) April 1979. CO-CHAIRMEN/WG.1/32(D) PINAL REPORT HEAVY WATER REQUIREMENTS AND AVAILABILITY, Prepared by INFCE Sub-Group ID 1979 October i CONTENTS Summary 1. Introduction 1.1 Participation in Study 1.2 Work Program and Organization of Work 1.3 Sub-Group ID Meetings 2. Heavy Water Demand Projections 2.1 Outline of Methodology for Reactor Capacity Projections 2.2 Outline of Methodology for Heavy Water Demand Projections 2.3 Demand Projections 3. Production Strategies to Meet Demand Projections 3.1 Upper and Lower Demand Limits 3.2 Demand Variability 3.3 Production Programs 3.3.1 Lead Tines 3.3.2 Self-Sufficiency 3.3.3 Heavy Water Plant Sizes 3.3.4 International Collaboration 4. Deuterium Sources 4.1 Water 4.2 Hyd rocarbons 4.3 Hydrogen 5. Heavy Water Production Technology 5.1 General Characteristics Common to All Processes 5.2 Commercial Heavy Water Processes 5.2.1 Water Distillation 5.2.2 Hydrogen Distillation 5.2.3 Electrolysis of Water 5.2.4 Chemical Exchange Processes 5.3 Hydrogen Sulflde-Water Process 5.* Ammonia-Hydrogen Process 5.5 Outlook for New and Improved Process Technology 5.5.1 Technology Developed to the Point of Demonstration 5.5.2 Technology Requiring Some Additional Development 5.5.3 Futuristic Technology 6. Industrial Infrastructure Required for Production Program 6.1 General Considerations 6.2 CS Process 6.^ Hydrogen-Fed Processes 6.4 Final Enrichment and Upgrading 11 CONTESTS (CONT'D) Heavy Water Plant Siting Considerations 7.1 Availability of Deuterium Source 7.2 Environmental Impact Considerations 7.3 Energy Supply Considerations Economic Factors Governing Heavy Hater Production Costs 8.1 Heavy Hater Market Structure 8.2 Cost Considerations 8.3 Pricing of Heavy Water Safeguards Considerations Summary of Findings References Tables Figures Appendices - iii - LIST OF TABLES Table 1 - Projected Nuclear Capacity by Reactor Type. Illustrative Single-Type Reactor Strategies, High Growth Case Table 2 - Projected Nuclear Capacity by Reactor Type, Illustrative Single-Type Reactor Strategies, Low Growth Case Table 3 - Projected Nuclear Capacity by Reactor Type, Illustrative Mixed Reactor Strategies Table 4 - Projected Heavy Water Requirement for Illustrative Single- Type Reactor Strategies, High Growth Case Table 5 - Projected Heavy Water Requirement for Illustrative Single- Type Reactor Strategies, Low Growth Case Table 6 - Projected Heavy Water Requirement for Illustrative Mixed Reactor Strategies Table 7 - Current Heavy Water Plant Capacity Table 8 - Some Heavy Water Processes Which Have Been Employed or Studied LIST OF FIGURES Figure 1 - Cumulative Heavy Water Requirement, High Growth Case Figure 2 - Cumulative Heavy Water Requirement, Low Growth Case Figure 3 - Annual Heavy Water Requirement, High Growth Case Figure 4 - Annual Heavy Water Requirement, Low Growth Case Figure 5 - Separation Factors for Chemical Exchange Processes Figure 6 - Simplified Monothermal Flowsheet With Gas Feed Figure 7 - Simplified Dual Temperature Flowsheet With Llq-iid Feed Figure 8 - Simplified GS Flowsheet With Two Stages and Gas Interstage Connections LIST OF APPENDICES Appendix 1 - List of WG ID Reports and Minutes of Meetings Appendix 2 - Questionnaire on Heavy Water Program Appendix 3 - List of WG ID Meetings - 1 - SUMMARY The heavy water demand projections based on the work of Sub-Group 1A/2A are presented. The projections are a reflection of a) national responses to a questionnaire on planned nuclear programs up to the year 2000 and on studies by the World Energy Conference and the Nuclear Energy Agency for the period 2000 to 2025. b) postulated scenarios or strategies regarding the mix of the various reactor types. These strategies are meant to be illustrative rather than predictive. Strategies involving rapid penetration of the HWR give rise to the largest heavy water requirements. Depending on the economic growth rate, these (cumulative) requirements are from 425 to 800 Gg by 2010 and 1150 to 2700 Gg by 2050. An annual requirement of 9 Gg/a in the year 2000 for the low growth case expands to 60 Gg/a by 2025. For the high growth case the annual requirement grows from 14 Gg/a to 155 Gg/a' in the same time period. For the so-called "mixed strategy" wherein the HWR captures an increasing share of the nuclear market after 2000 (approaching 40% by the year 2025), the heavy water demands are considerably less. For example, the cumulative requirement would expand smoothly from 25 Gg in 1990 through 450 Gg in 201C to 1200 Gg in 2025 for the high growth case. For the low growth case the corresponding requirements are 20, 250 and 550 Gg, respectively* Mixed strategies wherein the HWR captures a nuclear market share approaching 10% in the post-2000 period give rise to modest heavy water demands. For example, the cumulative demand grows to 300 Gg by 2025 for the high growth case and to 150 Gg for the low growth case. - 2 - Strategies involving increasing predominance of the LWR give rise to. minimum heavy water requirements. Sapid penetration of fast breeder reactors would result in heavy water requirements between those of the LWR- predominant situation and those of the mixed strategies wherein the HWR captures a market share approaching 10Z in the post-2000 period. For strategies involving rapid penetration of the HWR the period 2000-2005 is a time of particularly rapid growth in heavy water requirements. To service the growing requirements during this period 20 to 40 new production plants per year, each producing 400 Mg/a, would be required. Clearly, such a program would require good coordination of financial, technical and human resources. The heavy water requirement is more sensitive to the reactor mix than is the case for the requirement for fuel and enrichment services. The major reasons for this are firstly, only the HWR requires heavy water whereas all reactors require fuel and, secondly, the fuel and enrichment requirements depend on the total capacity of reactors in operation while the heavy water requirement depends on the rate at which the total capacity is being augmented through HWR additions. Addition rate is of course more variable than total- installed capacity. It takes less time to build a heavy water production facility than a nuclear power station. Since it is unlikely, however, that a heavy water plant committed at the same time as a HWR could produce all of the heavy water required for the initial reactor charge, advance planning of heavy water supplies to meet projected requirements Is necessary. - 3 - There appears to be little need at present for special institutional arrangements of an international nature to secure future world heavy water requirements• The main reserves of deuteriua are water and hydrocarbons. Hydrogen, which is produced from water and/or hydrocarbons is an intermediate from which deuterium can be extracted* The natural concentration of deuterium in most hydrogeneous substances is between 130 x 10~° and 150 x 10~6 atoms of deuterium per atom of hydrogen. The world's natural water systems constitute a virtually inexhaustible supply of deuterium at low concentration. Extraction from these water bodies of the quantities of deuterium which would be required for the most ambitious world HWR program conceivable would not have any measurable effect on the concentration that remains* While no economically feasible technology for extracting deuterium directly from hydrocarbons has yet been demonstrated, projected oil and gas recovery rates through to 2025 could easily enable all deuterium requirements to be met* Projected hydrogen availability is capable of supporting all heavy watar requirements of some reactor strategies* Heavy water production plants are generally large and both capital and energy intensive* This is a consequence of the fact that deuterium in the feed is present in very low concentration, hence large amounts of material must be processed, and because Isotope separation requires a large number of separative elements* - 4 - Deuterium separation technology currently available generally employs isotope exchange or distillation.
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