Light-water nuclear reactor

As seen from (2.56), separative work has the dimension of mass, and can be thought of as the mass flow rate multiplied by the time required to yield a given quantity of product. The cost of isotope sq>aration is obtained by assigning a value to one separative work mass unit (kgSW or SWU). A 1 GWe nuclear light water reactor station requires about 180 X 10 SWU in initial fueling and then 70 — 90 X 10 SWU for an annu reload. 

The objective of this paper is to discuss the safety issues associated with the immobilization of excess weapons plutonium in ceramic form in the United States. The U.S. government has recommended a dual-track approach to dispose of excess weapons plutonium. According to this approach, about 33 metric tons of pure Pu will be fabricated into mixed oxide (MOX) fuels which will be burned in commercial nuclear light water reactors and up to 17 metric tons of impure Pu will be immobilized into ceramic form which will be permanently disposed of in a geologic repository. It should be noted that a portion of the 33 metric tons of pure Pu may also be immobilized into ceramic form depending on the future decision of the U.S. government. 

An Aging Failure Survey of LWR Safely Systems and Components Nuclear 4 Tables of component failures per years of service Light Water Reactor Safety System Components 93. 

Characteristics of Pipe System Failures in Light Water Reactors Nuclear Approximately 100 records of pipe failure rates in a wide variety of failure modes Nuclear Power Plant Piping 114. 

Mixed oxide fuel is not appropriate for all nuclear reactors. Plutonium requires faster neutrons in order to operate in a sustained chain reaction. Light-water reactors operate in a highly moderated environment. 

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. 

The phrase "nuclear power" covers a number of technologies for producing electric power other than by burning a fossil fuel. Nuclear fission in pressurized water-moderated reactors—light water reactors— represents the enrrent teehnology for nuclear power. Down the line are fast breeder reactors. On the distant horizon is nnclear fusion. 

Jones, O. C., Jr., and S. G. Bankoff, 1977, Two-Phase Flow in Light Water Reactors, Proc. Symp. on Thermal and Hydraulic Aspects of Nuclear Reactors, ASME, Atlanta GA. (3)... 

The nuclear plants now operating in the U.S. are light water reactors, which use water as both a moderator and coolant. These are sometimes called Generation II reactors. In these Generation II Pressurized Water Reactors, the water circulates through the core where it is heated by the nuclear chain reaction. The hot water is turned into steam at a steam generator and the steam is used by a turbine generator to produce electric power. 

LDH LEU LIBD LAW LET LILW LIP LLNL LLW LMA LMFBR LOI LREE L/S LTA LWR Layered double hydroxide Low enriched uranium Laser-induced breakdown detection Low-activity waste Linear energy transfer Low- and intermediate-level nuclear waste Lead-iron phosphate Lawrence Livermore National Laboratory Low-level nuclear waste Law of mass action Liquid-metal-cooled fast-breeder reactor Loss on ignition Light rare earth elements (La-Sm) Liquid-to-solid ratio (leachates) Low-temperature ashing Light water reactor... 

The basic design of most nuclear reactors is similar, but several types of reactors are used throughout the world. In the United States most reactors use plain water as the coolant. Reactors using ordinary water are called light water reactors. Light water reactors can be pressurized to approximately 150 atmospheres to keep the primary coolant in the liquid phase at temperatures of approximately 300°C. The heat from the pressurized water is used to heat secondary water to generate steam. In a boiling water reactor, water in the core is allowed to boil. The steam produced powers the turbines directly. Heavy water reactors use water in... 

Although there have been comparatively few gas-cooled reactors installed for generating commercial nuclear electric power, the concept has a number of operating advantages over light-water reactors and could play an important role in the reactor designs for the next century. 

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