Radioactivity density measurement device null for radioactive waste enclosing container

摘要

PURPOSE: To obtain a measuring apparatus of activity concentration for a radioactive waste container which can measure the activity concentration of radioactive waste precisely and correctly irrespective of an activity concentration distribution. ;CONSTITUTION: In this measuring apparatus, a Ge detector 27 equipped with collimators 28 and 29 and a plurality of radiation intensity detectors 26 are disposed outside a radioactive waste container 21 so that they can be rotated and moved up and down in relation to this container 21, and each of the detectors 26 detects a radiation count rate signal for each unit of a virtual segment of a prescribed length in the height direction and for each unit of a necessary angle in the direction of rotation. A weight measuring device is provided and a computer 37 computing the average density of a radioactivity filled region from a determined net weight and the radiation count rate signal on the assumption that the capacity of the radioactivity filled region is fixed ' provided. By this computer 37, the amount of radioactivity in the vertical segment of the container 21 is calculated by executing computation for correction of absorption of γ rays of a substance in the container 21, and the amount of the radioactivity in the container 21 is determined by integrating the calculated amount of the radioactivity.;COPYRIGHT: (C)1994,JPO&Japio