Authors & Affiliations
Skobeev D.A., Legkikh A.Yu.
A.I. Leypunsky Institute for Physics and Power Engineering, Obninsk, Russia
Legkikh A.Yu. – — Leading Researcher, Cand. Sci. (Tech.), A.I. Leypunsky Institute for Physics and Power Engineering.
One of the tasks of ensuring safety when using a heavy liquid-metal coolant (HLMC) in nuclear reactors of a new generation is the need to remove hydrogen from the gas volume of the circulation circuits with HLMC. The main sources of hydrogen supply to the gas systems of reactor plants are the technological measures for hydrogen purification of the first circuit and the interaction of TWMT with water vapor at steam generator leaks. One of the main reasons for the need to remove hydrogen from the shielding gas of the first circuit of the reactor with HLMC is hydrogen safety. In the case of a beyond design basis accident with a depressurization of the first circuit, there is a possibility of air entering the gas-oxygen loop and forming a "rattling mixture". In the reactor with HLMC, an oxygen-free gas medium (argon, helium) is used as protective gas, which makes it impossible to use existing hydrogen removal devices used at operating nuclear power plants. A traditional way to reduce the concentration of hydrogen in an inert protective gas in research stands and nuclear submarines with HLMC is to repeatedly replace the gas or vacuum the gas system and then fill it with an inert gas. In the developed reactor plants with HLMC, such a method of reducing the hydrogen concentration is not expedient due to the large volumes of protective gas and the radiation safety standards. A promising method of hydrogen removal in the reactor with HLMC is the process of removal (afterburning) of hydrogen with metal oxides. This paper describes the proposed method for the removal of hydrogen by metal oxides and presents the methods and results of studies of the kinetics of the hydrogen removal process using granulated lead oxide. In the paper presented are the various methods of maintaining specified HLMC oxygen potential and approaches to their implementation based on the experience gained in operating various experimental facilities and power plants located in the research institutes of the Russian Federation.
heavy liquid metal coolant, hydrogen, hydrogen afterburner, remove, kinetics, topochemical reactions, nuclear reactor, constant of the reaction rate, gas mixture, recovery rate
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