Annual report on the effluent control of low level liquid waste in Nuclear Fuel Cycle Engineering Laboratories FY2017

Nakano, Masanao; Fujita, Hiroki; Mizutani, Tomoko; Nagaoka, Mika; Inoue, Kazumi; Koike, Yuko; Yamada, Ryohei; Yoshii, Hideki*; Hiyama, Yoshinori*; Otani, Kazunori*; et al.

JAEA-Review 2018-028, 120 Pages, 2019/02

JAEA-Review-2018-028.pdf:2.69MB

Based on the regulations (the safety regulation of Tokai Reprocessing Plant, the safety regulation of nuclear fuel material usage facilities, the radiation safety rule, the regulation about prevention from radiation hazards due to radioisotopes, which are related with the nuclear regulatory acts, the local agreement concerning with safety and environment conservation around nuclear facilities, the water pollution control law, and by law of Ibaraki Prefecture), the effluent control of liquid waste discharged from the Nuclear Fuel Cycle Engineering Laboratories of Japan Atomic Energy Agency has been performed. This report describes the effluent control results of the liquid waste in the fiscal year 2017. In this period, the concentrations and the quantities of the radioactivity in liquid waste discharged from the reprocessing plant, the plutonium fuel fabrication facilities, and the other nuclear fuel material usage facilities were much lower than the limits authorized by the above regulations.

Conceptual design study toward the demonstration reactor of JSFR

Sakai, Takaaki; Kotake, Shoji; Aoto, Kazumi; Ito, Takaya*; Kamishima, Yoshio*; Oshima, Jun*

Proceedings of 2010 International Congress on Advances in Nuclear Power Plants (ICAPP '10) (CD-ROM), p.521 - 530, 2010/06

JAEA is now conducting "Fast Reactor Cycle Technology Development (FaCT)" project for the commercialization before 2050s. A demonstration reactor of Japan Sodium-cooled Fast Reactor (JSFR) is planned to start operation around 2025. In the FaCT project, conceptual design study on the demonstration reactor has been performed since 2007 to determine the referential reactor specifications for the next stage design work from 2011 for the licensing and construction. Plant performance as a demonstration reactor for the 1.5 GWe commercial reactor JSFR is being compared between 750 MWe and 500 MWe plant designs. By using the results of conceptual design study, output power will be determined during year of 2010. In this paper, current status of the conceptual design study will be summarized with related research and developments on plant technologies.

Conceptual design for Japan Sodium-cooled Fast Reactor, 1; Current status of system design for JSFR

Uto, Nariaki; Sakai, Takaaki; Mihara, Takatsugu; Toda, Mikio*; Kotake, Shoji; Aoto, Kazumi

Proceedings of 2009 International Congress on Advances in Nuclear Power Plants (ICAPP '09) (CD-ROM), p.9298_1 - 9298_11, 2009/05

A conceptual design for JSFR and developments of innovative technologies are implemented. A compact RV has been designed to enhance the economy. The regarding development results have been reflected to the RV design. An innovative CV design has been implemented with elemental tests to reduce the construction cost. SASS and the NC DHRS have been designed to enhance the safety, with the irradiation data acquired in Joyo and the development of a 3-dimensional thermal-hydraulic evaluation method. An approach for ISI/R has been provided to be applicable for FR characteristics, and the developmental studies on innovative inspection technologies have been progressed. Other technologies including double-walled pipes with short elbows, a pump-integrated IHX are also being developed. These results, together with a preliminary conceptual design study on a demonstrative reactor for JSFR, will be utilized as resources in 2010 to determine which innovative technologies should be adopted.

Visualization of grease fluidity in a ball bearing using neutron imaging technology

Sakai, Kazumi*; Ogata, Rui*; Kimura, Nobuharu*; Matsumoto, Yoshihiro*; Kurita, Keisuke

no journal, , 

Neutron imaging technique was applied to visualize grease fluidity in bearings which determines the bearing torque property. Two types of lithium (Li) greases with different thickeners were used in this study. The Li complex grease was superior in lowering bearing torque related to energy-saving performance. After bearing rotations, neutron radiography and computed tomography measurements of the greases distributed in the bearings were performed. Adhesion of the Li complex grease to bearing balls was quite limited, and most of the grease stayed on cage surfaces between the balls; adhesion of single Li soap grease to bearing balls was remarkable. The neutron radiography with bearing rotations was also conducted to capture the moment of the grease flow. The observation with bearing rotations revealed that single Li soap grease flows gradually not from the beginning of bearing rotations. Based on these results, the lubrication mechanisms will be proposed.

An Experimental study on grease fluidity in a ball bearing using neutron imaging technology

Sakai, Kazumi*; Ogata, Rui*; Yamada, Shuhei*; Kimura, Nobuharu*; Matsumoto, Yoshihiro*; Kurita, Keisuke

no journal, , 

Rolling element bearings with grease lubrication are widely used for axis rotations in motors. Unlike liquid lubricants, the fluidity of semisolid greases in bearings plays an important role in bearing performances. The fluidity is often described as channeling and churning states. The states are well known, however, cannot be seen from outside bearings. Therefore, visualizations of greases in bearings are beneficial to understand the grease fluidity, however, methods for non-destructive observations of the inside of bearings are limited. The neutron imaging technology was applied for non-destructive observation of the grease fluidity inside a ball bearing in this study. The technology is based on a characteristic that neutron passes through heavy elements and interacts to light elements. In other words, neutron can identify lubricants with light elements inside the bearing with heavy elements.