O. V. Balan, L. I. Pavlovsky, V. M. Rudko, S. G. Brylka, S. S. Pidbereznyi
Institute for Safety Problems of Nuclear Power Plants, NAS of Ukraine, 36a, Kirovа st., Chornobyl, 07270, Ukraine
DOI: doi.org/10.31717/2311-8253.25.2.8
Abstract
The paper presents proposals for the technology of dismantling debris on the deck of the Deaerator Platform (DP), including the necessary equipment required for these operations. It is emphasized that dismantling debris within the scope of unstable structures removal is among the most challenging tasks in the implementation of this project. The main reason is the presence of numerous sources of ionizing radiation that differ in type, size, and intensity within the dismantling zone. This leads to technological challenges primarily related to ensuring radiation safety. The application of technologies based on the use of systems, mechanisms, and devices that allow for the complete elimination or significant minimization of personnel involvement in these operations is required. The main methods for using remotely controlled mechanisms, necessary both for debris dismantling and for subsequent waste handling, have been formulated. A basic flowchart of waste handling during debris dismantling on the DP deck has been developed, taking into account the sequence of dismantling activities. It is noted that operations involving large-sized reinforced concrete radiation-contaminated structures (CRCS) can be performed at the New Safe Confinement (NSC) temporary storage site, followed by transportation outside the NSC for disposal in near-surface storage facilities. Handling of loose radioactive waste (RW), as well as CRCS with above-standard radiation indicators (after conversion to a loose form), is carried out in the Process Building (PB), with subsequent transfer outside the NSC for containerized storage. It is emphasized that the experience gained from performing debris dismantling and waste-handling operations can be applied in the future and should be taken into account when planning the removal of fuel-containing materials (FCM) and other accumulations of materials and structures currently located at the upper, intermediate, and lower levels of the Shelter object.
Keywords: New Safe Confinement, Shelter Object, unstable structures, reusable container, main crane system, mobile instrumental platform, remotely controlled mechanism, radioactive waste management.
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