GRAPHITE STACK DISMANTLING APPROACHES UNDER DEMOLITION DECOMMISSIONING OPTION

“Demolition” decommissioning strategy is currently being followed up for RBMK, AMB and EGP-6 type uraniumgraphite commercial reactors. Nevertheless, practical experience on such reactor demolition, including graphite stack dismantlement, is not yet available. Technologies being developed to enable the dismantlement of nuclear power facilities should be primary based on optimization and feasibility principles. Given the existing setup, this requires that remote techniques are applied to the maximum extent possible. Under the Federal Targeted Program for Nuclear and Radiation Safety-2 (FTP NRS-2), JSC Pilot-Demonstration Center for Uranium-Graphite Nuclear Reactor Decommissioning has carried out R&Ds on the development of graphite stack dismantlement technology for the shutdown uranium-graphite commercial reactor ADE-5. The first stage of the project resulted in a flow sequence of operations and measures ensuring safety during the dismantlement of UGR metal structures located between the upper biological shielding and the graphite stack. Characteristics and the amounts of generated radioactive waste, personnel exposure and time have been evaluated. Engineering solutions on penetrating the upper biological shielding, dismantlement of reactor fuel channel elements, metal structures and graphite blocks in the stack’s upper layer have been developed.

Keywords: uranium-graphite reactor, graphite stack, dismantlement, metal structures, biological shield, technological sequence

Paderin E.S., Sheshin A.A., Orlov K.E. Graphite Stack Dismantling Approaches under “Demolition” Decommissioning Option. Radioactive Waste, 2019, no.3 (8), pp. 69—73.DOI: 10.25283/2587-9707-2019- 3-69-73. (in Russian).