フロン代替剤による活性炭フィルタの現場試験の経験

摘要

The activated carbon filters used in a nuclear power plant are subjected to in-place leak test prior to the plant start-up and also in the course of their annual periodic inspection. The method previously employed for the leak test was to feed a tracer gas, CFC R-112 in the upstream of a carbon filter and measure the gas concentration in both upstream and downstream of the filter. However, because CFC was a material causing the ozone layer destruction and so the production was decided to cease, substitute material for R-112 has been selected. This paper describes an outline of the conventional in-place leak test, using R-112, of activated carbon filters for a BWR nuclear power plant, the test equipment specially developed for applying the CFC substitute to the in-place leak test in the power plant, and the experiences of the test by means of the equipment.