METHOD FOR DETECTING NUCLEAR FUEL FRAGMENTS AND DETERMINING THEIR PARAMETERS IN NUCLEAR REACTOR GRAPHITE BLOCKS Russian patent published in 2023 - IPC G21C17/00 G01T1/167 

FIELD: nuclear facilities.

SUBSTANCE: invention relates to a method for detecting nuclear fuel fragments and determining their parameters in a graphite block of a nuclear reactor. The method includes measuring the intensity of gamma radiation and radiation of thermal and epithermal neutrons from the characterized graphite block, as well as estimating the size, shape and location of nuclear fuel fragments based on the analysis of experimental and calculated results using preliminary verified programs and constants. If the intensity values of gamma radiation of the fission product 137Cs and neutron radiation, measured during the extraction of the graphite block from the masonry by gamma and neutron radiation detectors installed in the internal axial hole of the capture of the graphite block, exceed the characteristic values of the background from the graphite block without fuel fragments, further measurements are done. Taking into account the received data, the graphite blocks are sorted at the containerization stage.

EFFECT: detecting, determining the mass of residual fragments of nuclear fuel in graphite blocks removed from the masonry of a nuclear reactor during dismantling.

1 cl, 8 dwg