Light Water Cooled Reactor Systems

1 In so far as gas cooled reactor systems are concerned, detailed recommendations in respect of further work are as follows  

2 As far as light water cooled reator systems are concerned the recommendations made in 2.4.1 (a), (b), (c), (d) and (e) apply in principle with respect to demolition and removal of the primary shield wall. In addition it is recommended that work be done to assess the feasibility of constructing the inner part of the primary shield wall to contain water tanks. 

3 For both reactor systems there are three simple measures which 

Involve no great design innovation but which could significantly aid the decommissioning process and it is recommended that these measures be adopted. These are to ensure that as many as 

3 In the meantime, however, the literature pointed to several features whose consideration for nuclear power plants being designed now, or in the immediate future, could aid their decommissioning and dismantling. 

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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... 

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

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. 

Y. Oka, S. Koshizuka, T. Jevremovic, Y. Ohno and K. Kitoh, Direct-Cycle Supercritical-Pressure, Light-Water-Cooled Reactors for Improving Economy and Plutonium Utilization, Proc. Global95, International Conference on Evaluation of Emerging Nuclear Fuel Cycle Systems, Versailles, France, September 11-14, 1995, 930-937 (1995)... 

The Hanford N Reactor. The Hanford N reactor was built in 1964 for purposes of plutonium production during the Cold War. It used graphite as moderator, pierced by over 1000 Zircaloy 2 tubes. These pressure tubes contained slightly enriched uranium fuel cooled by high temperature light water. The reactor also provided 800 MWe to the Washington PubHc Power Supply System. This reactor was shut down in 1992 because of age and concern for safety. The similarity to the Chemobyl-type reactors played a role in the decision. 

Water Reactors. After pressure to design Hanford eased, Wigner and his group turned to examination of other combinations of moderators, coolants, and fuel. The most thoroughly studied were the light-water cooled and moderated, and the heavy-water moderated systems. 

This order applies to all varieties of reactors including, but not limited to light water moderated reactors, heavy water moderated reactors, liquid metal cooled reactors, gas cooled reactors and short-pulse transient reactors. Space reactor power and propulsion systems and critical facilities require special design criteria. Attachment 4 is reserved for Nuclear Safety Design for critical facilities and space reactors. 

AR386 1.110 Cost-benefit analysis for radwaste systems for light-water-cooled nuclear power reactors... 

Uchida, H., Oyama, A. and Togo, Y. (1964) Evaluation of post-incident cooling systems of light water power reactors , A/Conf. 28/P/436, Geneva 1964 Conference on Peaceful Uses of Atomic Energy, UNO, Geneva, 1964. 

These three main lines, as defined by their primary coolant are water cooled, gas cooled, and liquid metal cooled. Water cooled reactors can be fiirther categorized as heavy water or light water moderated reactors. The design approach for a given system can be substantially different from another system within the same technology line. The small and medium reactor area has to deal with all technological lines and all varying approaches. The relevant reactor information for the purpose of this TECDOC has been divided into six parts ... 

CFR 50.44, "Standards for Combustible Gas Control System in Light-Water-Cooled Power Reactors , Office of the Federal Register, National Archives and Records Administration. 

The PSRD is an indirect cycle light water cooled tank-type small reactor with an integral design of the primary circuit. Steam generator is located inside the reactor vessel. The PSRD is designed to achieve system simplification, resulting in the reduction of costs for construction, operation and maintenance. The assessments of the plant economy are... 

CIRENE is a reactor concept belonging to the family of the heavy water moderated and boiling light water cooled systems. 

Acceptance Criteria for Emergency Core Cooling Systems for Light Water Cooled Nuclear Power Reactors, Title 10 Code of Federal Regulations Part 51.46, U.S. Atomic Energy Commission, Federal Register (January 4, 1974). 

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