Pressurized heavy water reactors

There are various types of nuclear power reactors, including boiling water reactors (BWR) and pressurized water reactors (PLWR or LWR), which are both light-water reactor (LWR) designs and are cooled and moderated by water. There also are pressurized heavy-water reactor (PHWR or HWR) designs. 

Pressurized filters, 11 324 Pressurized heavy water reactors (PHWRs), 24 758... 

Pressurized heavy-water reactor (PHWR) % 5 UO2 pellets (natural U) Zircaloy DnO D2O 280- 310 8 11 700 -800 8-10... 

Radioactive waste treatment applications have been reported [3-9] for the laundry wastes from nuclear power plants and mixed laboratory wastes. Another interesting application of reverse osmosis process is in decontamination of boric acid wastes from pressurized heavy water reactors (PHWRs), which allows for the recovery of boric acid, by using the fact that the latter is relatively undissociated and hence wdl pass with water through the membrane while most of the radioactivity is retained [10]. Reverse osmosis was evaluated for treating fuel storage pool water, and for low-level liquid effluents from reprocessing plants. 

Heavy water is not only the most important component, but also the major cost contributor to the nuclear power program, which utilizes pressurized heavy water reactors. 

Strokes CL, Buxbaum RE. Analysis of palladium coatings to remove hydrogen isotopes firom zirconium fuel rods in Canada deuterium uranium-pressurized heavy water reactors thermal and neutron diffusion effeds. Nud Technol. 1992 98 207. 

Pressurized heavy water reactor high-level waste... 

One of the technical problems of ranoval of tritium is its low concentration in technological and waste streams. In heavy water reactor moderator (pressurized heavy water reactor [PHWR]), the ratio of DTO to D2O is 10 , and in water... 

AR104 Aeeident analysis for nuelear power plants with pressurized heavy water reactors. No. 29, 19 November 2003. 

Consistent with these publications, the IAEA in 2002 issued a detailed report on Accident Analysis for Nuclear Power Plants (Safety Reports Series No. 23) that provides practical guidance for performing accident analysis. That report covers the steps required for accident analyses, i.e. selection of initiating events and acceptance criteria, selection of computer codes and modelling assumptions, preparation of input data and presentation of the calculation results. It also discusses aspects that need to be considered to ensure that the final accident analysis is of acceptable quality. Separate IAEA Safety Reports deal with specific features of individual reactor types, such as pressurized water reactors, boiling water reactors, pressurized heavy water reactors and RBMKs. 

Pressurized heavy water reactor "CANDU" (PHWR) Canada 33 18 Natural UO2 Heavy water Heavy water... 

PRESSURIZED HEAVY WATER REACTOR PHWR-500 SYSTEM DESCRIPTION AND DEVELOPMENT STATUS... 

The Atomic Energy Establishment was set up at Trombay, near Mumbai, in 1957 and renamed as Bhaba Atomic Research Centre (BARC) ten years later. Plans for building the first Pressurized Heavy Water Reactor (PHWR) were finalized in 1964, and fhis prototype, Rawatbhata-1, which had Canada s Douglas Point reactor as a reference unit, was built as a collaborative venture between Atomic Energy of Canada Ltd and NPCIL. It started up in 1972 and was duplicated. Subsequent indigenous PHWR development has been based on these units. 

The PHWR 300 of KWU is a pressurized heavy water reactor of the pressure vessel type with the following main characteristics ... 

Due to the low bum-up of the fuel firom the pressurized heavy water reactors, storage in transport containers has been chosen. Design studies for reinforced concrete casks with stainless steel lining indicate cost of around US 45 per kg uranium. At present pools and concrete silos assure the interim at-reactor storage. If rq>rocessing is decided, then the plant would also be installed in the proximity of the disposal site to minmiize risks and costs of transportation. 

A notable exception is provided by national experience of India, a developing country that is successfully ongoing with operation and construction of new nuclear power plants with the domestically produced pressurized heavy water reactors of 209 and 490 MW(e) net capacity. 

Most studies of the time evolution of the fuel cycle and the evolving mix of reactor types during future decades have been based on global (or national) nuclear energy demand scenario analyses which, up to now, have assumed the use of traditional reactor types, such as LWRs, pressurized heavy water reactors (PHWRs), and fast breeder reactors (FBRs). Possible implications of small reactors without on-site refuelling on the transition timing and strategy have not yet been assessed extensively. 

Figure VIII-1 shows a simplified schematic diagram of the nuclear steam supply system with the Package-Reactor. The concept resembles a calandria-type pressurized heavy water reactor (e.g., the FUGEN advanced thermal reactor (ATR) or CANDU reactors) since all these employ pressure tubes. But the Package-Reactor is somewhat different from the ATR or the CANDU. The Package-Reactor employs natural circulation with two-phase flow for core cooling and has no recirculation pumps. The height of the pressure tubes of the cassettes is required to be as low as possible to attain a compact unit. Two-phase flow with high void fractions similar to BWRs is adopted to attain natural circulation with a cassette height of 6 m and a fuel rod length of 3.65 m.

The use of programmable electronic systems is finding increasing use in Indian nuclear power plants. This paper reviews the evolution of the control instrumentation system in Indian pressurized heavy water reactors and highlights the areas where programmable electronic and computer based systems are used as well as details the plans for the future. 

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