Data acquisition related to improving operability of ROVs for the retrieval of HASWS stored waste

Tameta, Yuito; Sano, Kyohei; Takano, Yugo*; Yamamoto, Masahiko; Nakazaki, Katsutoshi; Akiyama, Kazuki

JAEA-Technology 2026-004, 27 Pages, 2026/05

JAEA-Technology-2026-004.pdf:3.18MB

At the High Active Solid Waste Storage (HASWS) of Tokai Reprocessing Plant, high active solid waste generated from the reprocessing process is stored. In the wet cell, hull cans containing fuel cladding tubes (hulls) and end pieces are stored, along with used filters and contaminated equipment. It is being considered that utilizes a small underwater remotely operated vehicle (ROV) along with a lifter for recovering and transporting objects from the seafloor for the retrieval of the waste stored in the HASWS. Mock-up tests were conducted in FY2022 and FY2023 to verify the feasibility of retrieving waste using the ROV and the lifter. In this study, to achieve safer and more reliable waste retrieval, improvements were made to each component, including the ROV cable, waste gripping grab, lifting hook, lifter, and ROV monitoring camera, and data were collected to evaluate operational performance. For the ROV cable, attaching a float to the rear section of the ROV cable to reduce its weight facilitated forward-tilt operation and improved the ROV's attitude stability during wire-cutting. For the waste gripping grab, attaching a jig to the tips of the grab of the lifter (grabtype) enhanced the gripping stability of the hull can. For the lifting hook, setting the ring diameter of the lifter (hook-type) to 15 cm shortened the time required for grasping and improved accessibility to the hook. For the lifter, using lifters with modified internal structures enabled fine air-volume adjustment and reduced blockage of air passages, thereby improving the stability of air supply and exhaust. For the ROV monitoring camera, adding a light near the ROV monitoring camera in a dark environment ensured sufficient cell illumination and enhanced cable visibility.

Fast Reactor Cycle Technology Development Project (FaCT Project); A Design study on an engineering-scale hot test facility (Interim report)

Nakamura, Hirofumi; Nagai, Toshihisa; Suto, Toshiyuki; Kosaka, Ichiro; Nakazaki, Katsutoshi; Suto, Shinya; Nakamura, Tomotaka; Nakabayashi, Hiroki; Hayashi, Naoto; Sumida, Daisaku

JAEA-Technology 2008-077, 276 Pages, 2008/12

JAEA-Technology-2008-077.pdf:25.66MB

Japan Atomic Energy Agency (JAEA) has been conducting "Fast Reactor Cycle Technology Development Project (FaCT Project)" for the purposes of researching and developing the technologies for the fast breeder reactor cycle commercialization since Japanese fiscal year (JFY) 2007. Based on the above R&D program for reprocessing system, the engineering-scale hot test would provide demonstration data on the specification, operation and maintenance of the adapted innovative technologies, system and plant. And more, these results would be fed to the design of the demonstration facility planning on the FaCT project road map. This report is the interim report of design studies about the engineering-scale hot test facility and includes not only design of the equipment and facility, but also consideration for design principle, requirements and facility basic planning.

Development of the measurement technology of inside melter, 2

Nakazaki, Katsutoshi; Takaya, Akikazu; Kato, Junya; Kobayashi, Masahiro; Matsumura, Tadayuki; Niitsuma, Koichi; Fujiwara, Koji

no journal, , 

no abstracts in English

Development of advanced vitrification melter, 16; Examination on the discharge of particulate in vitrified waste

Nakazaki, Katsutoshi; Morikawa, Yo; Yamashita, Teruo; Sasage, Kenichi; Nakajima, Masayoshi

no journal, , 

no abstracts in English

Development of advanced vitrification melter, 15; Evaluation of temperature of wall by the small scale melter

Yamashita, Teruo; Masaki, Toshio; Nakajima, Masayoshi; Nakazaki, Katsutoshi; Toyoshima, Mikihiro

no journal, , 

no abstracts in English