Light water-cooled reactors

Note that the only other plutonium production site in the U.S. was at Richland, Wa.shington where graphite-reflected light water cooled reactors were used. 

Oka, Y. Physics of supercritical-pressure light water cooled reactors. Proc. 1998 Frederic Joliot Summer School in Reactor Physics, Caderache, France, and references cited herein, 1998 240-259 pp. 

AR405 1.133 Loose-part detection program for the primary system of light-water-cooled reactors... 

Uranium enrichment and fuel fabrication For light-water-moderated and light-water-cooled reactors (LWRs) and for advanced gas-cooled graphite moderated reactors (AGRs), the uranium processed at the mills needs to be enriched in the hssile isotope Enrichments of 2-5% are required. Before the enrichment, the uranium oxide (UsOg) must be converted to uranium tetra-fluoride (UF4) and then to uranium hexa-fluoride (UFg). 

The Initial brief for the study was that It should consider only civil engineering aspects of nuclear power plants based on gas cooled reactor systems. The brief, however, was extended to Include an assessment of the civil engineering aspects of decommissioning light water cooled reactor systems, particularly the pressurised water reactor. 

DECOMMISSIONING OF LIGHT WATER COOLED REACTOR SYSTEMS... 

Regulatory Guide 1.133, Rev. 1, "Loose-Part Detection Program for the Primary System of Light-Water-Cooled Reactors", U.S. Nuclear Regulatory Commission, May 1981. 

ANSI/ANS 4.5, "Criteria for Accident Monitoring Functions in Light-Water-Cooled Reactors", December 1980. 

HWLWR Heavy Water Moderated, Light Water Cooled Reactor... 

When a nitrogen atom freshly produced by a nuclear reaction is broken away from an H2O molecule, the thermalized nitrogen atom may react with various radicals, ions and molecules in the immediately surrounding area of the aqueous phase. In a high radiation field, such as exists in the core of a light-water cooled reactor, the principal reaction partners will be the products of water radiolysis. In earlier laboratory studies (Schleiffer and Adloff, 1964) the following chemical forms and distribution of N produced in pure water were identified ... 

There are 11 concepts of small reactors without on-site refuelling that are currently being developed at different stages in the Russian Federation. Six of them are light water cooled reactors the UNITHERM (ANNEX II), the ELENA (ANNEX III), the VBER-150 (ANNEX IV), the ABV (ANNEX V), the KLT-20 (ANNEX VI), and the VKR-MT (ANNEX X). In addition, there is one small gas cooled fast reactor concept which is the BGR-300 (ANNEX Xm) two sodium cooled reactor concepts the MBRU-12 (ANNEX XVI), and the BN GT-300 (ANNEX XVItl) and one lead-bismuth cooled small reactor design, the SVBR-75/100 (ANNEX XIX). Finally, there is one non-conventional reactor concept the MARS (ANNEX XXVIII). 

There are 6 concepts of small reactors without on-site refuelling that are currently being developed at early stages in the United States of America. Two of them are light water cooled reactors, the MASLWR (ANNEX I) and the AFPR (ANNEX XI). There is one lead-bismuth cooled reactor concept, the ENHS (ANNEX XX). Finally, three lead cooled reactor concepts form the so-called STAR reactor family. These are the SSTAR (ANNEX XXII), the STAR-LM (ANNEX XXIII), and the STAR-H2 (ANNEX XXIV). 

The use of micro fuel elements is being considered for WER-1000 reactors [X-2] and for a direct-flow light water cooled reactor with superheated steam at core outlet, a concept developed by the Pacific Northwest National Laboratory (PNNL, USA). However, both these reactors are not SMRs. The Fixed Bed Nuclear Reactor (FBNR) described in this report incorporates certain design approaches that could be of relevance to the VKR-MT. 

X-5] GRISHANIN, E.I., DENISOV, E.E., LIUBIN, A.YA., FALKOVSKY L.N.,. Mathematical model for calculation of coolant parameters in fuel assembly of light water cooled reactor with micro fuel elements. Tyazheloye Mashinostroyenie, No. 9, 11-20 (1995, in Russian). 

Oka, Y., Mori, H. (Eds.), 2014. Supercritical-Pressure Light Water Cooled Reactors. Springer, Tokyo, ISBN 978-4-431-55024-2. 

Figure 4.1 Schematic of the high-performance light water-cooled reactor (HPLWR) core design concept [8].

Y. Oka, S. Koshizuka, Y. Ishiwatari, A. Yamaji, Super Light Water Reactors and Super Fast Reactors Supercritical-pressure Light Water Cooled Reactors, Springer, New York, 2010. 

Beyond the present use of generation II-III light water-cooled reactors (LWRs), it is essential to develop the Generation IV breakthrough technologies listed below ... 

Figure 16.3 The vertical bars display the temperature interval between the onset of interstitial migration and the onset of vacancy migration in several pure metals and ceramics [7]. The horizontal bars show the approximate operating temperatures for structural materials in the cores of current light water-cooled reactor (LWR) power plants and proposed Generation IV sodium-cooled fast reactors (SFRs).

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