Optimizing the Process for Chemically Decontaminating the Multiple Forced Circulation Circuit of Power Units Built around RBMK Reactors

摘要

It is shown that, when the multiple forced circulation circuit of power units built around RBMK-1000 reactors undergoes chemical decontamination in accordance with the standard procedure, the decontaminating solution is unnecessarily kept in circulation over the circuit for as long as a few days. A criterion is proposed that establishes the moment at which the process of transfer of loose deposits from the surfaces of equipment into the volume of coolant reaches completion. This allowed us to reduce the time taken for the circulation to proceed by an order of magnitude and to increase the amount of radionuclides removed from the multiple forced circulation circuit by a factor of 15 as compared with that removed when the standard procedure of chemical decontamination is carried out.