Lead-bismuth transfer behavior preliminary test in liquid sodium. Effect of test temperature and amount of lead-bismuth on reaction behavior

The simplified secondary sodium cooling system, in which utilized lead-bismuth eutectic is utilized as an intermediate coolant has been selected as one of candidate system for the 'Feasibility Studies on Commercialized Fast Reactor System (Phase I)'. The purpose of this study for the 'FS (Phase II)' is to understand transfer behavior of lead-bismuth in liquid sodium by experiment. The experiments which trickles liquid lead-bismuth into liquid sodium are carried out of under various test temperature and amount of lead-bismuth. The effects of test temperature and amount of lead-bismuth on reaction behavior of sodium and lead-bismuth are clarified from the experimental results. The obtained results from experiments are as follows. (1) The experiment under lower test temperature takes longer time for reaction between sodium and lead-bismuth than that under higher test temperature. It means that test temperature affects the reaction behavior between sodium and lead-bismuth. (2) The amount and kind of reaction products which are formed by reaction between sodium and lead-bismuth depend on an amount of dropping lead-bismuth. (3) Reaction heat obtained from the experiments is similar to estimated reaction heat using formation enthalpy of BiNa3 which is one of dominant reaction products. (author)