[2N04-06] Decommissioning of Reprocessing Plant, and Transport Package

10:35 AM - 10:50 AM JST(1:35 AM - 1:50 AM UTC)

[2N05] Flush-out for Tokai Reprocessing Plant decommissioning(4) Removal of the U solution

*masayuki ohuchi¹, yoshiyuki kishi¹, hiroyasu isobe¹, takeshi yasuda¹, yuji yada¹, shohei suzuki¹, hayate tokoro¹, shota kusaka¹, keita shoji¹, hirotaka samoto¹ (1. Japan Atomic Energy Agency)

Keywords:

Tokai Reprocessing Plant,decommissioning,Flush-out,U solution

Tokai Reprocessing Plant (TRP) retained nuclear materials such as spent fuel sheared powder, plutonium solution, and uranium solution due to TRP shift to decommissioning in anticipation of resuming reprocessing. Flush-out to sequentially remove these nuclear fuel materials was required for future decommissioning of equipment.U solution was denitrified to UO₃ powder as the final stage of flush-out, stored in the uranium storage. We performed inspections and training, simultaneously transferring technical knowledge to young engineers. Safe and stable processing was achieved by establishing conditions that could treat lower-concentration U solution and prevent nozzle clogging. Additionally, by denitrifying the diluted U solution in the feed tank, the washing waste was significantly reduced. Through these efforts, flush-out for TRP was successfully completed.