Sodium safety issues in nuclear power plants
Giovanni Manzini
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Abstract
The international nuclear power community has proposed six new Generation IV nuclear reactor designs for use later this century. These include reactors cooled by gas, lead and water, as well as high molten salt reactors and the SFR (Sodium-cooled Fast Reactor) [1] (Figure ). To support the development of these innovative reactors, a wideranging research and development programs are now under way. A number of technology goals lie on the research -for example, improving nuclear safety and reliability; sustainability and minimizing waste; and reducing the cost of building and running nuclear plants. The SFR, in particular, is a fast-neutron spectrum one with a closed fuel cycle for efficient conversion of fertile uranium and management of actinides. The SFR reactor uses a fast neutron spectrum and liquid sodium as coolant to remove the heat from the core. In effects, the liquid sodium is an excellent cooling agent, mainly because of his its good heat transfer capabilities, low melting point (97.8 °C at p= 1 atm) and large margins to the boiling point (883 °C, at p= 1 atm) at ambient pressure and also low viscosity. The SFR can increase the efficiency of uranium usage by breeding plutonium and it is designed to allow any transuranic isotope to be consumed (and in some cases used as fuel). In practice, due to the its fast neutron spectra, SFR has the capability to utilize almost all of Energia & Ricerca LA TERMOTECNICA luglio/agosto 2012
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