| abstract |
(57) [Summary] [PROBLEMS] To surely detect leakage of a partition wall of a multiple pipe. SOLUTION: High-pressure cooling water Wa flows in an inner pipe 1a of a multiple pipe 1, and low-pressure cooling water Wb flows between an inner pipe 1a and an outer pipe 1b. When Kr is added to the high-pressure cooling water Wa by the addition pipe 11 in the case where the leakage portion 2 exists in the inner pipe (partition wall) 1a, Kr enters the low-pressure cooling water Wb through the leakage portion 2. The low-pressure cooling water Wb is sampled by the sampling pipe 12 and sent to the stripping tower 20. In the stripping tower 20, the Kr gas separated by the gas-liquid separation action is mixed with the He gas. The He gas mixed with the Kr gas is analyzed by the mass spectrometer with gas chromatography 44, and if Kr is detected, it can be determined that the leak portion 2 exists. |