Peach bottom reactor

The HTGR designed by the General Atomic Company and constructed at Peach Bottom, Pennsylvania, U.S.A., was a 40 MW(e) experimental power plant which was similar in many respects to the Dragon reactor. Peach Bottom started commercial operation on June 1, 1967, and ceased operation on October 31, 1974 [36]. The major performance parameters of the Peach Bottom Reactor are shown in Table 8. 

Table 8. The major performance parameters of the Peach Bottom Reactor [29]...

The fuel for the Peach Bottom reactor consisted of a uranium-thorium dicarbide kernel, overcoated with pyrolytic carbon and silicon carbide which were dispersed in carbon compacts (see Section 5), and encased in graphite sleeves [37]. There were 804 fuel elements oriented vertically in the reactor core. Helium coolant flowed upward through the tricusp-shaped coolant channels between the fuel elements. A small helium purge stream was diverted through the top of each element and flowed downward through the element to purge any fission products leaking from the fuel compacts to the helium purification system. The Peach... 

The LS-VHTR uses the same type of coated-particle graphite-matrix fuel that has been successfully used in high-temperature gas-cooled reactors such as the Peach Bottom Reactor, the Fort St. Viain Reactor (FSVR), the Arbeitsgemeinshaft Versuchsreaktor (AVR), and the Thorium High-Temperature Reactor (THTR). At this time, graphite-based fuels have been demonstrated to be compatible with only two coolants helium and fluoride salts. 

Experiments on simple pyrolytic-graphite-coated particles in the GAIL-III B fuel element showed that Xe having a half-life of 100 hr, for example, was held up sufficiently long for about 99 % of the decay to occur within the fuel element, even after an exposure corresponding to 3 years with an 80% load factor in the Peach Bottom reactor (41). The release fraction for this isotope was, then, about 10 at the end of the fuel exposure life. Release fractions for Kr , Kr , and Kr , for example, having half-lives in the neighborhood of 1 hr, were about 10 at the end of the fuel exposure. The measurements showed that the release fractions increased approximately linearly with exposure. 

In the Peach Bottom reactor, the release of fission products to the main coolant is further limited by the low-permeability graphite sleeve. The maximum helium permeability of this sleeve is 3 x 10 cm /sec, whereas the effective permeability to the heavier gaseous fission products at operating conditions is less than 1 x 10 cm /sec. The retention properties of the sleeve are such that the fission-product release fraction through the sleeve is of the order of 10 to 10 . Hence, the overall release fractions for the Xe and Kr isotopes having half-lives less than about 100 hr are well below 10 ... 

Experience of the Th -U cycle was first obtained in the Indian Point boiling water reactor, where the first core, loaded in 1962, contained pellets of urania-thoria mixture. The main interest, however, has centered on its use in the high-temperature gas-cooled reactor (HTGR), and thorium has been employed as fertile material both in the prismatic fuel elements of the Dragon reactor in the United Kingdom and the Peach Bottom reactor in the United States, and in the spherical elements of the pebble-bed AVR in West Germany. There is also a possibility of adopting the thorium cycle in the... 

Malinauskus, A.P., de Nordwall, H.J., Dyer, F.F., Wichner, R.P., Martin, W.J. and Kolb, J.O., Fission product behavior during operation of the second Peach Bottom core. In Proceeding of the Symposium on Gas-Cooled Reactors with Emphasis on Advanced Systems, Vol. 1, IAEA-SM-200/50, IAEA, Vienna, 1976, pp. 237 249. 

H. 1 Design of Reaction Engineering Experiment 953 H.2 Effective Lubricant Design 953 H.3 Peach Bottom Nuclear Reactor 953 ... 

MW-d/tonne. In-pile loop tests of a full-diameter Peach Bottom element showed satisfactory behavior after an exposure approximating that specified for the reactor. Capsule tests on triplex-coated particles have been carried to 200,000 MW-d/tonne at 1370°C with no significant damage to the particles 40). 

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