Liquid metal cooled reactors

It should be mentioned that boiling within a liquid metal-cooled reactor (such as a sodium-cooled reactor) is an accident condition and may give rise to rapid fuel failure. In designing a reactor core, on the other hand, sodium boiling should... 

Step by step solution to the project on long-term storage of spent fuel from nuclear submarines with heavy liquid metal cooled reactors... 

The first three submarine reactors disposed of in this way seems have originated from a Hotel, a November and a Yankee class submarine, all of early designs, and they had all suffered either a criticality or a loss-of-cooling accident. They were all provided with two pressurized water reactors. The submarine was the Project 645 submarine with a November class hull, which was provided with two liquid-metal cooled reactors. It had suffered a loss-of-cooling accident in one of its reactors [4]. 

There are many different types of reactors. In the United States, the majority of the reactors are pressurized water reactors with graphite moderators. The Canadians built the CANDU reactor using heavy water as both moderator and coolant. Naval ship reactors are graphite moderated liquid metal cooled reactors. The detailed differences between the reactor types will not be examined, but the operating principal common to all will be discussed. 

LMFRs(liquid metal cooled reactor) have been under development for more than 50 years. Twenty LMFRs have been constructed and operated. Five prototype and demonstration LMFRs (BN-350/Kazakstan, Phenix/France, Protot3q)e Fast Reactor/UK, BN-600/Russian Federation, Super Phenix/France) with electrical output ranging from 250 to 1200 MW(e) and large scale (400 MW(th)) experimental fast flux test reactor FFTF/USA have gained nearly 110 reactor-years. In total, LMFRs have gained nearly 310 reactor-years of operation. 

The USA/GE advanced liquid metal cooled reactor (ALMR) was designed to provide high reliability for the key safety functions, including reactor shutdown, heat removal, and containment. These functions can be achieved by passive means (thermal expansion, temperature effects on neutron absorption, natural circulation of the sodium coolant, and natural air circulation). 

Liquid metal cooled reactors (LMR) have been under development for more than 40 years, and several have been built and operated on commercial power grids. Sodium has been generally used as the coolant in these systems, and experience with this technology has been mixed. Sodium leaks have been the most notable technical issue, and the fact that sodium is very chemically reactive with air and water has contributed to most of the concerns about LMRs. The technolo is clearly still developmental even though there is considerable valuable experience. 

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. 

ALMR advanced liquid-metal (-cooled) reactor... 

Passive safety systems similar to gas-cooled and liquid-metal-cooled reactors engineered in the 1980s and 1990s, especially the Super Power Reactor Inherently Safe Module (S-PRISM) design developed by General Electric (GE). ... 

The concept of a liquid metal-cooled reactor dates back to the genesis of nuclear energy. The first nuclear reactor to generate electricity was the liquid sodium-potassium-cooled fast reactor Experimental Breeder Reactor-1 (EBR-1) [5]. EBR-Fs successor, the sodium-cooled fast reactor (SFR) EBR-11 operated successfully for over 30 years, producing 20 MW of electricity via a sodium-steam power cycle [6]. 

W. Kwant and C. E. Boardman, PRISM—Liquid Metal Cooled Reactor Plant Design and Performance, Nucl. Eng. Des., 136, 111, 1992. 

Chapters 6 through 8 give an introductory look at the liquid metal cooled reactor system, the molten salt reactor, and also the small modular reactor systems. Chapter 9 introduces the Gen IV reactor design concepts that have been developed by the United States Department of Energy (USDOE). 

In light water reactors, the radionuclides are exclusively deposited into the surface oxide layers of the piping, components, etc., while the base materials (with the exception of the materials inside the reactor pressure vessel which are neutron-activated) are free of radioactivity. This fact is a fundamental difference from reactors that operate at higher temperatures (e. g. liquid-metal cooled reactors), where the deposited radionuclides are able to diffuse into the base material to a significant... 

TABLE 5. LIQUID METAL COOLED REACTORS (a) Sodium cooled... 

Table 3 lists technical specifications for small autonomous reactors Table 4 contains specifications for water cooled reactors Table 5 gives data for liquid metal cooled reactors and Table 6 presents the characteristics for high temperature lead, gas, or molten salt cooled reactors. 

TABLE 7. LIQUID METAL COOLED REACTOR CONCEPTS WITH NEARER-TERM DEPLOYMENT POTENTIAL... 

Of all small reactors without on-site refuelling in this report, about half are liquid metal cooled reactors with fast neutron spectrum they include the following concepts (see Table 5) ... 

Slightly over a third of the concepts represent thermal spectrum water cooled fuelled reactors designed to operate in a once-through fuel cycle. Slightly under half of the concepts are fast spectrum liquid metal cooled reactors, in most cases providing for the operation in a closed fuel cycle. 

BROWN, N. W., et al.. Liquid metal cooled reactors and fuel cycles for international security, ICONE-11 (Proc. 11 Int. Conf. on Nuclear Engineering, Tokyo, Japan, 2003), ASME. 

SUPER-SAFE, SMALL AND SIMPLE LIQUID METAL COOLED REACTOR (4S-LMR, CRIEPI DESIGN)... 

The Central Research Institute of Electric Power Industry (CRIEPI, Japan) is developing a small-sized Super-Safe, Small and Simple liquid metal cooled reactor (4S-LMR), which is a sodium cooled nuclear reactor of 50 MW(e) being designed for use as a distributed energy source with multi-purpose applications. Design development for the 4S-LMR is performed jointly with the Toshiba Corporation (Japan). 

XVm-11] INTERNATIONAL ATOMIC ENERGY AGENCY, Status of Liquid Metal Cooled Reactor Technology, IAEA-TECDOC-1083, Vienna (April 1999). 

GREENSPAN, E., ELIAS, E., KASTENBERG, W.E., STONE, N., Nonproliferation liquid metal cooled reactors for developing countries. Center for Nuclear and Toxic Waste Management, University of California, CNTWM 98-2 (Feb. 15, 1998). 

The LFR system provides for ambient pressure single-phase primary coolant natural circulation heat transport and removal of core power under all operational and postulated accident conditions. The high boiling temperature of the Pb coolant enables heat transport by natural circulation of the primary coolant at significantly higher temperatures than with traditional liquid metal cooled reactors. External natural convection driven passive air-cooling of the guard/containment vessel is always in effect and removes power at decay heat levels. 

XXII-17] GYOREY, G.L., HARDY, R.W., MAGEE, P.M., Safety design for the advanced liquid-metal-cooled reactor. Nuclear Safety, Technical Progress Journal, Oak Ridge National Laboratory, USA, Vol. 31, p. 323 (1990). 

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