DEVELOPMENT OF SWEEP GAS SENSOR WITH PROTON CONDUCTION

To obtain engineering data for a design of a fusion blanket, a program in which a mock-up simulating a blanket structure is irradiated is pr oceeded in the JMTR (Japan Materials Tasting Reactor) project.(1) It i s indispensable for this irradiation test to purge the tritium produce d in the mock-up by the sweep gas and to measure the tritium concentra tion in the sweep gas on line. However, the bad effects such as tritiu m adsorption on the inner surface of the pipe and tritium diffusion fr om the pipe are apprehended, because the distance between the mock-up and an ionization chamber is about 20m long. Therefore, it is necessar y to develop a sweep gas sensor which can measure the tritium concentr ation in the mockup directly without the above apprehension. A sweep g as sensor had been fabricated on trial and several performance tests w ere carried out. From the results of the tests, it was found that this sensor could be used at the atmosphere of high temperature of 600-700 degrees C and had good response.