Liquid metal coolants

These meters have been very useful for handling liquid metal coolants where the conductivity is high though they have now been developed for liquids such as tap water which have a poor conductivity. Designs are now available for all sizes of tubes, and the instrument is particularly suitable for pharmaceutical and biological purposes where contamination of the fluid must be avoided. 

Nuclear and magneto-hydrodynamic electric power generation systems have been produced on a scale which could lead to industrial production, but to-date technical problems, mainly connected with corrosion of the containing materials, has hampered full-scale development. In the case of nuclear power, the proposed fast reactor, which uses fast neutron fission in a small nuclear fuel element, by comparison with fuel rods in thermal neutron reactors, requires a more rapid heat removal than is possible by water cooling, and a liquid sodium-potassium alloy has been used in the development of a near-industrial generator. The fuel container is a vanadium sheath with a niobium outer cladding, since this has a low fast neutron capture cross-section and a low rate of corrosion by the liquid metal coolant. The liquid metal coolant is transported from the fuel to the turbine generating the electric power in stainless steel... 

UNLOADING, STORAGE AND SUBSEQUENT MANAGEMENT OE SPENT NUCLEAR EUEL OE LIQUID-METAL-COOLANT REACTORS ACTUAL STATUS AND PROBLEMS... 

The paper addresses the aetual status and the main problems of unloading, storage and subsequent management of Spent Nuelear Fuel (SNF) of Russian Nuclear Submarines (NSs) with lead-bismuth Liquid-Metal Coolant (LMC) in the primary circuit. On this basis some topical tasks related to analysis of the sources of potential radiation releases and risk assessment are formulated and discussed. 

Land-based Stands-prototypes of Power Reaetor Installations (PRI) of Liquid-Metal Coolant (LMC) NSs... 

Ignatiev, C., Pankratov, D., Toshinskiy G., et al. (2004) Nuclear and Radiation Safety during Spent Nuclear Fuel Storage of Land-based Stands Prototypes of Naval Liquid-metal Coolant Power Reactor Installations - Final Report under the ISTC Project 2710p between the Russian Research Center Institute for Physics and Power Engineering (RRC IPPE) and the Brookhaven National Laboratory of the US Department of Energy, Obninsk (in Russian). 

Proceedings of the Conference Heavy Liquid-metal Coolants in Nuclear Technologies v. 1, pp. 80-83, Obninsk (in Russian). 

Spent removable parts (SRP) imloading from reactor vessels with liquid metal coolant (LMC) was carried out in the period from 1966 to 1990. The unloaded SRP s were assumed to be held in the storage facility for a short period of time to be followed by their shipment for reprocessing. Currently each unloaded SRP is being stored in the clean (non-radioactive), frozen lead-bismuth alloy in special steel containers located inside concrete pits. The storage time has not been specified yet. 

However so far the problem of storage of non-reprocessible fuel (e.g., SNF of liquid-metal-coolant reactors) has been neither raised nor properly formulated yet. The presence of non-reprocessible SFAs at CMBs should be also considered imder this problem. 

From the above table it follows that major works in different areas are to be performed in Gremikha including -management of SNF of Nuclear Submarines (NSs) with Liquid-Metal Coolant (LMC) reactors and WER -management of Solid and Liquid Radioactive Waste (SRW and LRW) -removal of SNF and Spent Removable Units (SRUs) to Mayak for reprocessing -rehabilitation of buildings, constructions, terrestrial and aquatic systems. 

In compliance with the closed fuel cycle concept accepted in Russia, SNF imloaded from Nuclear Submarines (NSs) with water-cooled reactors (WER) as well as SNF of nuclear icebreakers are forwarded to PA Mayak for reprocessing, fuel of liquid-metal coolant reactors, zirconimn-cladding fuel and damaged Spent Fuel... 

Erdman, C.A., Reynolds, A.B., Radionuclide behaviour during normal operation of liquid-metal-coolant fast breeder reactors. Part I Production. Nucl. Safety, 16 (1975) 43. 

The central cylindrical section surrounded by magnetic field coils will be long, possibly as long as 100 meters. The surface of the cylinder will be fabricated with channels to carry the liquid metal coolant. Each end of the cylindrical section would be fitted with an electrostatic/ magnetic end cap to prevent excess leakage of the plasma from the ends. The magnetic field used to confine the plasma would rely on superconducting coils to minimize the power required to sustain the confinement fields. 

Data on the properties of lithium alloys as liquid metal coolants have not been reviewed by the authors. However, with this approach, it may be possible to make use of lithium s excellent physical properties and overcome some of its adverse chemical properties. 

Based on its physical properties alone, lithium metal would appear to have no equal as a liquid metal coolant. However, because of corrosion caused at elevated temperatures by impurities in commercially available lithium and by the metal iself, lithium has found only experimental use as a liquid metal coolant. 

However, given that there is now this tendency for countries to have their own viewpoint and their own preferred option evolutionary sodium-cooled LMFR models or an innovative one with new coolant (gas, steam, other than sodium liquid metal coolants), it is essential to clarify as far as possible the scientific issues related to the different innovative options and to exchange information on advances in development of traditional and innovative fast reactors. 

F.A. KOZLOV, et al., Liquid Metal Coolants for Nuclear Power , Moscow, Energoatomizdat, 1983 (Rus). 

P.L. KIRILLOV, N.B. DENISKINA, "Themophysical Properties of Liquid Metal Coolants. Tables and Correlations". Review FEI-0291. Obninsk, IPPE, 2000 (Rus). 

Market values of the aforementioned liquid metal coolants are summarized in Table 4.5. 

TABLE 4.5. MARKET VALUE OF LIQUID METAL COOLANTS (US /tonnes)... 

In order to predict the direction of corrosion and mass transfer, it is essential to have data on thermodynamic properties of chemical compositions and steel components as a function of temperature. If the liquid metal is flowing at high velocity, the material is subject to erosion. Formation of the film (consisting of both steel and liquid metal coolant components) on the structural metal surface is another type of corrosion, since this is not protective film. Due to the difference in chemical activity between sodium and lead, technologies of these coolants are quite different, although some methods share a number of common features. 

The principle solutions ensuring high corrosion resistance of structural materials in heavy liquid metal coolant were found using oxygen dissolved in the coolant. It has been shown as a result of long-term studies that this corrosion resistance essentially depends on concentration of dissolved oxygen. 

Yu. F. BALANDIN, V. G. MARKOV, Materials for Systems with Liquid Metal Coolants , Moscow, Atomizdat, 1961 (Rus). 

P.L. KIRILLOV, Report presented to Int. Conf Heavy Liquid Metal Coolants , Obninsk, Russia, Oct. 5-9, 1998. 

A. V. ZHUKOV, et al, Thermohydraulic Design of Fast Reactor Fuel Subassemblies with Liquid Metal Coolant , Moscow, Energoatomizdat, 1985. 

In the summary [7.4] it was concluded that the sodium coolant appears to be the most appropriate for realisation of the non-waste goal among three liquid metal coolants considered . 

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