Method and arrangement for detecting leaks of nuclear fuel

摘要

Method and arrangement for detecting leaks of nuclear fuel in a nuclear reactor with a reactor core in the form of at least one fuel cartridge 2 which is lowered in water and comprises a number of fuel rods. Gas and/or water samples are taken in the vicinity of the fuel cartridge while measures are taken in order to force fission products out of fuel rods. A sample which has been taken is pumped up and supplied to a gas separator 7 comprising a gas space 8 and a water reservoir 9 and in which the gas space is separated from the water reservoir by means of a water lock 10. The water is finely distributed for supply to the gas space, and gas released from the sample is mixed with gas present in the gas space and the gas circuit 12 connected to the gas space. The gas mixture obtained is pumped to a measuring chamber 13 and is analysed for the presence of gaseous fission products. Degassed water is conducted to the water reservoir and is analysed for the presence of water- soluble fission products.