[2C06-09] TRU Waste

[2C06] Research and development of TRU waste package

(1)Overview

*Naoki Fujii¹, Hitoshi Owada¹, Noriyuki Maruyama¹, Hiroyuki Sakamoto¹, Hiroshi Sekiguchi¹ (1. RWMC)

Keywords:TRU Waste, Waste Package, Remote welding, Stress corrosion cracking, Waste Package Infill, Hydrogen Gas Generation

In the geological disposal of TRU waste, it is assumed that the waste package containing the waste and filler in a metal container will be collected and disposed of in a large cross-section disposal tunnel. In a series of studies, we developed the waste package shown in NUMO Pre-siting SDM-based Safety Case, unlike the waste package without a lid shown in the Second TRU Report. The package encloses waste in a metal container and has the ability to confine radioactive substances from operation to several hundred years after closure. This overview mainly introduces problems and approaches in the production process. In welding and encapsulation of metal containers, it is a problem to establish a remote welding technology capable of reducing residual stress that causes stress corrosion cracking, and to reduce the thermal effect on waste during welding and post-weld heat treatment. On the other hand, it is a problem to make the filler in the waste package by showing the specifications that can suppress the generation of hydrogen gas due to the radiolysis of the cement-based material.