DECONTAMINATION METHOD AND DEVICE FOR LIQUID METAL COOLED NUCLEAR REACTOR EQUIPMENT AND NUCLEAR REACTOR FACILITY EQUIPPED WITH THE DEVICE

摘要

PURPOSE:To remove contaminants on a surface of equipment uniformly and to leave no impurity in a coolant by raising a concentration of elements which accelarate a dissolving velocity of radioactive substances contained in a circulating liquid metal, when the equipment is decontaminated. CONSTITUTION:A lid of a dissolution tank 1 is opened and then an equipment 3 which is an object to be decontaminated, is soaked into a liquid Na 2 in the dissolution tank 1, and after that, the lid is put on the tank and an inert gas is filled to an upper space in the dissolution tank 1. Subsequently, each temperature of a heater 4 and a cooler 7 is set, respectively. Then, a pump 9 is actuated and therewith the liquid Na 2 which contains a high concentration oxygen is made to circulate through the dissolution tank 1, a piping, a concentration controller 6, another piping, a trap 21, a pump 9 and the dissolution tank 1 again, in series. With this procedure, a surface of the equipment dissolves out uniformly and radioactive corrosion products which thermally diffuse on the surface, dissolve into the liquid Na.