Reduction of the source term of an assumed criticality accident in a fuel fabrication facility with solution system. (15th December 2021)

• Record Type: Journal Article
• Authors: Fukaya, Yuji; Goto, Minoru
• Is Part Of: Annals of nuclear energy. Volume 164(2021)
• Publication Date: 2021-12-15
• Subjects: Criticality accident -- Environmental impact assessment -- Source term -- Fuel fabrication facility -- Public exposure; Nuclear energy -- Periodicals; Nuclear engineering -- Periodicals; 621.4805
• DOI: 10.1016/j.anucene.2021.108617
• Languages: English
• ISSNs: 0306-4549

Abstract

Highlights: A mechanism of criticality accident in a fuel solution system is investigated. A fission number determined by radiation decomposition hydrogen gas is proposed. The efficiency is confirmed by an environmental impact assessment. Abstract: A reasonable source term of a hypothetical criticality accident in a fuel fabrication facility with a solution system has been proposed. The public exposure must not exceed the limitation of 5 mSv during an accident. Then, we proposed as a reasonable source term of the first burst peak due to the hydrogen gas generation by radiation decomposition of water. With the criticality control system composed of the Criticality Accident Alarm System (CAAS) and a soluble neutron absorber, safety is ensured by the reduced fission number. We confirmed the effect by environmental impact assessment during a criticality accident by using the site condition of a fuel fabrication facility in Tokai-mura, Japan. As a result, the public exposure was reduced at a site boundary from 68 mSv to 0.6 mSv which is under the current regulatory guideline.