Present state of partitioning and transmutation of long-lived nuclides, 1; Significance of partitioning and transmutation and partitioning and transmutation systems

Minato, Kazuo; Tsujimoto, Kazufumi; Tanabe, Hiromi*; Fujimura, Koji*

Nihon Genshiryoku Gakkai-Shi ATOMO, 59(8), p.475 - 479, 2017/08

no abstracts in English

Development of a fast reactor for minor actinides transmutation, 1; Overview and method development

Takeda, Toshikazu*; Usami, Shin; Fujimura, Koji*; Takakuwa, Masayuki*

Proceedings of 21st International Conference & Exhibition; Nuclear Fuel Cycle for a Low-Carbon Future (GLOBAL 2015) (USB Flash Drive), p.560 - 566, 2015/09

The Ministry of Education, Culture, Sports, Science and Technology in Japan has launched a national project entitled "technology development for the environmental burden reduction" in 2013. The present study is one of the studies adopted as the national project. The objective of the study is the efficient and safe transmutation and volume reduction of minor actinides with long-lived radioactivity and high decay heat contained in high level radioactive wastes by using sodium cooled fast reactors. We are developing MA transmutation core concepts which harmonize efficient MA transmutation with core safety. To accurately design the core concepts we have improved calculation methods for estimating the transmutation rate of individual MA nuclides, and estimating and reducing uncertainty of MA transmutation. The overview of the present project is first described. The method improvement is presented with numerical results for a minor-actinide transmutation fast reactor.

Method development and reactor physics data evaluation for improving prediction accuracy of fast reactors' minor actinides transmutation performance

Takeda, Toshikazu*; Hazama, Taira; Fujimura, Koji*; Sawada, Shusaku*

Proceedings of International Conference on the Physics of Reactors; The Role of Reactor Physics toward a Sustainable Future (PHYSOR 2014) (CD-ROM), 15 Pages, 2014/09

A national project started in 2013 in Japan entitled "technology development for the environmental burden reduction". The present study is one of the studies adopted as the national project. We are aiming to develop MA transmutation core concepts harmonizing MA transmutation performance with core safety and to improve design accuracy related to MA transmutation performance. To validate and improve design accuracy of the high safety and high MA transmutation performance of SFR cores, we develop methods for calculating the transmutation rate of individual MA nuclides and estimating uncertainty of MA transmutation by using burnup sensitivity. Also we develop reliable reactor physics database to reduce the uncertainty of MA transmutation calculations. The overall consistency of the measured data is investigated by evaluating the usefulness of conventional static data as well as those related to MA transmutation obtained from various facilities like Monju, Joyo, FCA, BFS and PFR.

Comparison between TRU burning reactors and commercial fast reactor

Fujimura, Koji*; Sanda, Toshio*; Ogawa, Takashi*

JNC TJ9400 2001-015, 85 Pages, 2001/03

JNC-TJ9400-2001-015.pdf:2.4MB

Research and development for stabilizing or shortening the radioactive wastes included in spent nuclear fuel are widely conducted in view point of reducing the environmental impact. Especially it is effective way to irradiate and transmute long-lived TRU by fast reactors. Two types of loading way were previously proposed. The former is loading relatively small amount of TRU in all commercial fast reactors and the latter is loading large amount of TRU in a few TRU burning reactors. This study has been intended to contribute to the feasibility studies on commercialized fast reactor cycle system. The transmutation and nuclear characteristics of TRU burning reactors were evaluated and compared with those of conventional transmutation system using commercial type fast reactor based upon the investigation of technical information about TRU burning reactors. Major results are summarized as follows. (1) Investigation of technical information about TRU burning reactors. Based on published reports and papers, technical information about TRU burning reactor concepts and transmutation system using conventional commercial type fast reactors were investigated. Transmutation and nuclear characteristics or R&D issue were investigated based on these results. (a) Homogeneously loading of about 5wt% MAs on core fuels in the conventional commercial type fast reactor may not cause significant impact on the nuclear core characteristics. Transmutation of MAs being produced in about five fast reactors generating the same output is feasible. (b) The helium cooled MA burning fast reactor core concept propose by JAERI attains criticality using particle type nitride fuels which contain more than 60 wt% MA. This reactor could transmute MAs being produced in more than ten 1000 MWe-LWRs. (c)Ultra-long life core concepts attaining more than 30 years operation without refueling by utilizing MA's nuclear characteristics as burnable absorber and fertile nuclides were proposed. (d)Those ...

Study on the minor actinide transmutation utilizing Monju data, 2; Study on the MA transmutation core concept

Fujimura, Koji*; Oki, Shigeo; Takeda, Toshikazu*

no journal, , 

no abstracts in English

Study on the minor actinide transmutation utilizing Monju data, 6; Conceptual design study on the homogeneous MA loaded core concept

Fujimura, Koji*; Ogawa, Takashi*; Oki, Shigeo; Takeda, Toshikazu*

no journal, , 

no abstracts in English

Study on the minor actinide transmutation utilizing Monju data, 12; MA transmutation representative reactor core

Fujimura, Koji*; Shirakura, Shota*; Oki, Shigeo; Takeda, Toshikazu*

no journal, , 

no abstracts in English