[2D13-17] Decommissioning Technology for Fukushima 2

[2D14] Development for Dust Evaluation Method during Fuel Debris Retrieval Operations

(1)Overview of the Plan as well as the Examination of dust evaluation test system

*Yasuhiro Yuguchi^1,2, Chiaki Shimoda^1,2, Jun Suzuki^1,2, Kenji Kurihara^1,2 (1. IRID, 2. TOSHIBA ESS)

Keywords:Decommissioning, Fuel debris, Dust, Cutting, Particle size distribution, Fuel debris retrieval

During the fuel debris retrieval operations at the Fukushima Daiichi Nuclear Power Plant, dust particles in various sizes spread around a point where fuel debris is cut and handled by the remotely operated tools in the Primary Containment Vessel (PCV). It is required to develop a dust diffusion evaluation and prevention system in order to reduce radiation exposure to the public and workers. The purpose for this study is to evaluate the dust transfer rates from a cutting point to the air or to containment water as well as decontamination factors applied to the cutting tools. The overview of the development plan, including the dust diffusion prevention systems for the cutting tools, and the examination of dust evaluation test system in consideration of fuel debris mockup specimens are presented.