Advanced and High-Temperature Gas-Cooled Reactors [antikvár]

FOREWORD Gas-cooled graphite-moderated reactors using natural uránium fuel are well established in the production of electricity on an industrial scale. Theyhave provided the basic technology for the development of the advanced gas-cooled reactor, which uses slightly enriched uránium dioxidé elad in stainless steel and shows a considerable improvement in terms of economics. An AGR prototype plánt has operated very satisfactorily since early 1963 and commercial stations totalling 3700 MW(e) are now under construction in the United Kingdom. A further advance is represented by the high-temperature gas-cooled reactor using coated-partiele fuel and hélium as the coolant. Two reactors using prismatic fuel and one using the pebble-bed concept have satisfactorily demonstrated the new techno-logical features of these systems and the first commercial station is already being built. The HTR offers good fuel utilization, high thermal efficiency, and low fuel inventory, and can use several alternative fuel cycles, princi-pally the 235U/thorium-cycle and the low-enrichment uránium cycle. The system has considerable scope for further development, particularly in the use of a closed-cycle gas turbine, and much of the technology will be applicable to gas-cooled fast breeder reactors. The Symposium on Advanced and High-Temperature Gas-cooled Reactors, organized by the International Atomic Energy Agency in co-operation with the Government of the Federal Republic of Germany, and held in Jíilich on 21-25 October 1968, gave an opportunity to review available experience with such plants; new and advanced designs; develop-ments intechnology, fueland materials; fuelcycles; safety; and economics and potential. The wide interest in the meeting and its timeliness were evidenced by the fact that there were over 350 participants representing 24 countries and seven international organizations. The final session ofthe Symposium took the form of a panel discussion on the future prospects of these reactors. It was pointed out that the AGR had opened the way to úrban siting because of its safety features, particularly the use of a prestressed concrete pressure vessel. The HTR should allow similar flexibility in siting, while its ability to change from one type of fuel cycle to another could be an important asset. It was agreed that, in the near term, these reactors must compete against the water reactors for a suitable share of the expanding nuclear power markét. In the longer term, studies indicated that the HTR could offer competition to the fast breeders, but would alsó be an excellent supplement to them. In presenting these proceedings, which include 52 papers and a record of the discussions, the Agency wishes to thank the authors, session chairmen, members of the panel and participants, all of whom contributed to the success of the Symposium. Special thanks are due to the staff of the Kernforschungsanlage Jülich for their most valuable assistance in organizing the meeting.