Uranium-based TRU multi-recycling with thermal neutron HTGR to reduce environmental burden and threat of nuclear proliferation

Fukaya, Yuji; Goto, Minoru; Ohashi, Hirofumi; Yan, X.; Nishihara, Tetsuo; Tsubata, Yasuhiro; Matsumura, Tatsuro

Journal of Nuclear Science and Technology, 55(11), p.1275 - 1290, 2018/11

AA2017-0752.pdf:1.25MB

https://doi.org/10.1080/00223131.2018.1492983

To reduce environmental burden and thread of nuclear proliferation, multi-recycling fuel cycle with High Temperature Gas-cooled Reactor (HTGR) has been investigated. Those problems are solved by incinerating TRans Uranium (TRU) nuclides, which is composed of plutonium and Minor Actinoide (MA), and there is concept to realize TRU incineration by multi-recycling with Fast Breeder Reactor (FBR). In this study, multi-recycling is realized even with thermal reactor by feeding fissile uranium from outside of the fuel cycle instead of breeding fissile nuclide. In this fuel cycle, recovered uranium by reprocessing and natural uranium are enriched and mixed with recovered TRU by reprocessing and partitioning to fabricate fresh fuels. The fuel cycle was designed for a Gas Turbine High Temperature Reactor (GTHTR300), whose thermal power is 600 MW, including conceptual design of uranium enrichment facility. Reprocessing is assumed as existing Plutonium Uranium Redox EXtraction (PUREX) with four-group partitioning technology. As a result, it was found that the TRU nuclides excluding neptunium can be recycled by the proposed cycle. The duration of potential toxicity decaying to natural uranium level can be reduced to approximately 300 years, and the footprint of repository for High Level Waste (HLW) can be reduced by 99.7% compared with GTHTR300 using existing reprocessing and disposal technology. Suppress plutonium is not generated from this cycle. Moreover, incineration of TRU from Light Water Reactor (LWR) cycle can be performed in this cycle.

Optimization of disposal method and scenario to reduce high level waste volume and repository footprint for HTGR

Fukaya, Yuji; Goto, Minoru; Ohashi, Hirofumi; Nishihara, Tetsuo; Tsubata, Yasuhiro; Matsumura, Tatsuro

Annals of Nuclear Energy, 116, p.224 - 234, 2018/06

AA2017-0381.pdf:0.87MB

https://doi.org/10.1016/j.anucene.2018.02.031

Optimization of disposal method and scenario to reduce volume of High Level Waste (HLW) and the footprint in a geological repository for High Temperature Gas-cooled Reactor (HTGR) has been performed. It was found that HTGR has great advantages to reducing HLW volume and its footprint, which are high burn-up, high thermal efficiency and pin-in-block type fuel, compared with those of LWR and has potential to reduce those more in the previous study. In this study, the scenario is optimized, and the geological repository layout is designed with the horizontal emplacement based on the KBS-3H concept instead of the vertical emplacement based on KBS-3V concept employed in the previous study. As a result, for direct disposal, the repository footprint can be reduced by 20 % by employing the horizontal without change of the scenario. By extending 40 years for cooling time before disposal, the footprint can be reduced by 50 %. For disposal with reprocessing, the number of canister generation can be reduced by 20 % by extending cooling time of 1.5 years between the discharge and reprocessing. The footprint per electricity generation can be reduced by 80 % by extending 40 years before disposal. Moreover, by employing four-group partitioning technology without transmutation, the footprint can be reduced by 90 % with cooling time of 150 years.

Report of lower end plug welding, and test and inspection for the JOYO 6th refueling core fuel assembly

Kajiyama, Tadashi; Numata, Kazuaki; Otani, Seiji; *; *; Goto, Tatsuro*; Takahashi, Hideki*

JNC TN8440 2000-010, 45 Pages, 2000/02

JNC-TN8440-2000-010.pdf:1.45MB

This report describes about procedure and consequence of the welding process of the cladding tube and the lower end plug, the process of the test and inspection and the process of shipment for the 6th refueling core fuel assembly (46 fuel assemblies) of the experimental fast reactor JOYO. These works were carried out on July, 1996 from January, 1993 in Tamatukuri inspection branch of quality assurance section, technical administration division, plutonium fuel center. The 6th refueling core fuel assemblies are two kinds of the fuel assembly (1) and (2). The material of the lower end plug and the cladding tube used for the fuel assembly (1) is the type 316 stainless steel grade (here in after referred to as SUS316 grade) and austenitic stainless steel of high nickel content (here in after referred to as PNC 1520). That material used for the fuel assembly (2) is all SUS316 grade. The result of welding and the inspection is shown in the following table.

An investigation report on the defective occurrence of the lower end plug welded section for JOYO MK-III.; An investigation result about the inclusion occurrence

Kajiyama, Tadashi; Numata, Kazuaki; Otani, Seiji; Goto, Tatsuro*; Takahashi, Hideki*

JNC TN8430 2000-007, 44 Pages, 2000/02

JNC-TN8430-2000-007.pdf:5.32MB

Fabrication of the cladding tube with the lower end plug for the core fuel assembly of the experimental fast reactor JOYO and the proto-type fast breeder reactor MONJU has been performed by Tamatsukuri inspection branch of quality assurance section, Technical administration division, Plutonium fuel center since 1989. The fabrication process of the cladding tube with the lower end plug consists of numbering process of fuel element number to the lower end plug, welding process of the lower end plug and the cladding tube, and inspection process after welding (visual inspection, dimensional inspection and X-ray radiography). The processing of cladding tube with the lower end plug which is used for the initial loading core fuel assembly of JOYO MK-III has been carried out from August to May in 1996. The many tungsten inclusions were observed by X-ray radiography in the welds of the cladding tube with the lower end plug that were fabricated in the fourth fabrication campaign performed from July to August in 1996. The investigation of the causes was carried out about the welding process of the cladding tube and the lower end plug based on the fabrication record. The following three items were confirmed as a result. (1)As for the ingredients of inclusions observed by the X-ray radiography, it was proved by EPMA(Electron Probe X-ray Micro-analyzer) analysis that it was the same as the tungsten electrode. (2)Cracks, chips and consumption were observed in the tip of the electrodes used for welding of the lower end plug. And, cracks and chips were observed in the electrodes as well which hadn't been used. (3)It was proved that the tip of the electrode was exhausted remarkably when the distance between the tip of the electrode and the welding section became less than 0.08mm. (here in after to as the distance between the electrodes) Based on the above result, examination of reappearance for the inclusion generation was performed simulating the shape of cracks and chips ...

None

*; Kawata, Tomio*; Kaneda, Kenichiro; *; Goto, Tatsuro*; *

PNC TN841 84-67, 187 Pages, 1984/04

PNC-TN841-84-67.pdf:10.68MB

no abstracts in English

Simultaneous measurement of fission and capture cross sections for minor actinide nuclei

Tamura, Nobuyuki; Nishio, Katsuhisa; Hirose, Kentaro; Nishinaka, Ichiro; Makii, Hiroyuki; Kimura, Atsushi; Ota, Shuya*; Andreyev, A. N.; Vermeulen, M.*; Gillespire, S.*; et al.

no journal, , 

no abstracts in English