Safety conditions for the RBMK-1000 reactor with full unloading of fuel from the active zone after the final stop of the NPP

The article discusses approaches to ensuring the safety of the RBMK-1000 reactor during its decommissioning, including the complete removal of fuel from the reactor core. The article outlines the principles of safety based on regulatory requirements and the need to ensure critical safety functions for a permanently shut down reactor. The authors analyze the limits and conditions of safe operation, taking into account the specific characteristics of the reactor's operational state during its decommissioning. The expediency of automating the functions of analyzing the readings of neutron flux sensors, diagnosing the available reserves up to their sensitivity thresholds, and generating recommendations for repositioning the sensors within a separate system of information support for personnel at the stage of unloading nuclear fuel from the reactor core has been noted. The safety conditions for the RBMK-1000 reactor presented in the article, which involve the complete unloading of nuclear fuel from the core, can be used as a basis for developing a method for building an information support system for RBMK-1000 reactor units during their preparation for decommissioning.

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