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Umino, Yoshinori; Kato, Keisuke; Tanigawa, Masafumi; Kobayashi, Daisuke; Obu, Tomoyuki; Kimura, Yuichi*; Nemoto, Ryo*; Tajiri, Kazuma*
Nihon Hozen Gakkai Dai-19-Kai Gakujutsu Koenkai Yoshishu, p.33 - 36, 2023/08
In the basic laboratory of the Plutonium Conversion Development Facility in Tokai Reprocessing Plant, tests had been conducted to obtain effective data for manufacturing mixed plutonium and uranium oxide powder by irradiating a mixture of plutonium and uranium solution with microwaves. The test has already been completed, and we are currently dismantling and removing equipment. In this paper, techniques related to equipment renewal, dismantling and removal works inside the glove-box are discussed.
Rodriguez, D.; Tanigawa, Masafumi; Seya, Michio; Nakamura, Hironobu
Proceedings of IAEA Symposium on International Safeguards; Building Future Safeguards Capabilities (Internet), 6 Pages, 2018/11
-ray pipe-monitoring capabilities for real-time process monitoring safeguards applications in reprocessing facilitiesRodriguez, D.; Tanigawa, Masafumi; Nishimura, Kazuaki; Mukai, Yasunobu; Nakamura, Hironobu; Kurita, Tsutomu; Takamine, Jun; Suzuki, Satoshi*; Sekine, Megumi; Rossi, F.; et al.
Journal of Nuclear Science and Technology, 55(7), p.792 - 804, 2018/07
Times Cited Count：0 Percentile：0.01(Nuclear Science & Technology)Nuclear material in reprocessing facilities is safeguarded by random sample verification with additional continuous monitoring applied to solution masses and volume in important tanks to maintain continuity-of-knowledge of process operation. Measuring the unique rays of each solution as the material flows through pipes connecting all tanks and process apparatuses could potentially improve process monitoring by verifying the compositions in real time. We tested this ray pipe-monitoring method using plutonium-nitrate solution transferred between tanks at the PCDF-TRP. The rays were measured using a lanthanum-bromide detector with a list-mode data acquisition system to obtain both time and energy of -ray. The analysis and results of this measurement demonstrate an ability to determine isotopic composition, process timing, flow rate, and volume of solution flowing through pipes, introducing a viable capability for process monitoring safeguards verification.
-ray pipe monitoring for comprehensive safeguards process monitoring of reprocessing facilitiesRodriguez, D.; Tanigawa, Masafumi; Mukai, Yasunobu; Isomae, Hidemi; Nakamura, Hironobu; Rossi, F.; Koizumi, Mitsuo; Seya, Michio
Proceedings of INMM 58th Annual Meeting (Internet), 9 Pages, 2017/07
Safegaurding nuclear material at reprocessing facilities utilizes sampling to verify the quantity and process monitoring to maintain continuity-of-knowledge to reduce re-verification. Solution Monitoring and Measurement Systems that determine the solution density and volume are installed at solution tanks, though this only provides indirect verification. To offset this safeguards limitation we propose measuring rays from solutions passing through the pipes and at the tanks to provide improved continuous monitoring and direct verification. This can provide both real-time flow measurements and Pu isotopic composition quantification through passive nondestructive assay. This concept was tested by recent experimental studies performed at the Japan Atomic Energy Agency's Plutonium Conversion Development Facility of flowing Pu-nitrate rays. This presentation will describe the concept details and analysis of using ray pipe monitoring as a capability for real-time safeguards verification.
Takahashi, Naoki; Suzuki, Soju; Saito, Hiroto; Ueno, Takashi; Abe, Sadayoshi; Yamanaka, Atsushi; Tanigawa, Masafumi; Nakamura, Daishi; Sasaki, Shunichi; Mine, Tadaharu
Nihon Genshiryoku Gakkai Homu Peji (Internet), 20 Pages, 2017/05
no abstracts in English
He replacement technologies; Development of HLNB counterTanigawa, Masafumi; Mukai, Yasunobu; Nakamura, Hironobu; Kurita, Tsutomu; Henzlova, D.*; Menlove, H. O.*
Dai-37-Kai Kaku Busshitsu Kanri Gakkai Nihon Shibu Nenji Taikai Rombunshu (CD-ROM), 9 Pages, 2017/02
no abstracts in English
Sekine, Megumi; Matsuki, Takuya; Suzuki, Satoshi; Tanigawa, Masafumi; Yasuda, Takeshi; Yamanaka, Atsushi; Tsutagi, Koichi; Nakamura, Hironobu; Tomikawa, Hirofumi; LaFleur, A. M.*; et al.
EUR-28795-EN (Internet), p.788 - 796, 2017/00
The IAEA has proposed in its long-term R&D plan, the development of technology to enable real-time flow measurement of nuclear material as a part of an advanced approach to effective and efficient safeguards for reprocessing facilities. To address this, JAEA has designed and developed a neutron coincidence based nondestructive assay system to monitor Pu directly in solutions which is after purification process and contains very little fission products (FPs). A new detector to enable monitoring of Pu in solutions with numerous FPs is being developed as a joint research program with U.S. DOE at the High Active Liquid Waste (HALW) Storage Facility in Tokai Reprocessing Plant. As the first step, the design information of HALW tank was investigated and samples of HALW was taken and analyzed for Pu concentration and isotope composition, density, content of dominant nuclides emitting ray or neutron, etc. in order to develop a Monte Carlo N-Particle Transport Code (MCNP) of the HALW tank. In addition, ray source spectra simulated by Particle and Heavy Ion Transport code System (PHITS) was developed by extracting peaks from the analysis data with germanium detector. These outputs are used for the fundamental data in the MCNP model which is then used to evaluate the type of detector, shielding design and measurement positions. In order to evaluate available radiations to measure outside the cell wall, continuous ray and neutron measurement were carried out and the results were compared to the simulation results. The measurement results showed that there are no FP peaks above 3 MeV. This paper presents an overview of the research plan, characteristics of HALW, development of source term for MCNP, simulation of radiation dose from the HALW tank and radiation measurement results at outside of cell wall.
He-alternative HLNC-type counter; High Level Neutron counter-Boron (HLNB)Henzlova, D.*; Menlove, H. O.*; Tanigawa, Masafumi; Mukai, Yasunobu; Nakamura, Hironobu
EUR-28795-EN (Internet), p.313 - 323, 2017/00
Facing the depletion of He gas supply and the continuing uncertainty of options for future resupply, Los Alamos National Laboratory (LANL) designed and built a He free full scale thermal neutron coincidence counter based on boron-lined parallel-plate proportional technology. The counter was designed as a direct alternative to High Level Neutron Coincidence counter (HLNC-II). This paper provides a summary of performance evaluation of HLNB under realistic field conditions at Plutonium Conversion Development Facility (PCDF) of Japan Atomic Energy Agency (JAEA). The field test included a range of small to large mass MOX materials that represent realistic process samples and provided key insight on and validation of the feasibility of HLNB as a safeguards instrument in realistic facility environment. In particular, the results of verification measurements demonstrate that HLNB is capable to satisfy ITV expected for HLNC-II-type counter of 2.1% in 300s measurement time.
Matsuki, Takuya; Masui, Kenji; Sekine, Megumi; Tanigawa, Masafumi; Yasuda, Takeshi; Tsutagi, Koichi; Ishiyama, Koichi; Nishida, Naoki; Horigome, Kazushi; Mukai, Yasunobu; et al.
Proceedings of INMM 57th Annual Meeting (Internet), 9 Pages, 2016/07
The International Atomic Energy Agency (IAEA) has proposed in its long-term research and development (R&D) plan, development of a real-time measurement technology to monitor and verify nuclear material movement continuously as part of an advanced approach to effectively and efficiently conduct safeguards for reprocessing facilities. Since the Tokai Reprocessing Plant (TRP) has solutions containing both Pu and fission products (FP), a new detector development project to monitor Pu with FP is being carried out from 2015 to 2017. This project is mainly conducted in the High Active Liquid Waste Storage (HALWS) in the TRP. For the first step of this project, as the confirmation of composition of high active liquid waste (HALW) to evaluate neutron/-ray emitted from solution in the selected HALW tank which has the most amount of Pu in HALW tanks at the TRP, we took HALW sample and conducted -ray spectrum measurement for HALW. As a study of detector setting location, to survey the available neutron/-ray (i.e. intensity) at the outside surface of the cell where HALW tank is located, we implemented continuous measurement by neutron/-ray detector. In this paper, we report three -ray peaks related with 
Pu and 
Pu measured in the composition research of HALW, which is needed to identify Pu amount by the new detector that we are developing and the result of radiation measurement on the surface of the cell.
Sekine, Megumi; Matsuki, Takuya; Tanigawa, Masafumi; Tsutagi, Koichi; Mukai, Yasunobu; Shimizu, Yasuyuki; Nakamura, Hironobu; Tomikawa, Hirofumi
Proceedings of INMM 57th Annual Meeting (Internet), 9 Pages, 2016/07
The International Atomic Energy Agency (IAEA) has proposed in its long-term research and development plan, development of a real-time measurement technology to monitor and verify nuclear material movement continuously as part of an advanced approach to effectively and efficiently conduct safeguards for reprocessing facilities. In the reprocessing plant, since solutions containing both Pu and FP exist, a new detector development project to monitor Pu with FP is being carried out from 2015 to 2017. This project is mainly conducted in the High Active Liquid Waste Storage (HALWS) in Tokai Reprocessing Plant (TRP). In this paper, an overview of the technology development, simulation results of preliminary evaluation of the characteristics of radiation emitted from the HALW tank at TRP, and the future research plan are presented.
Tanigawa, Masafumi; Mukai, Yasunobu; Tobita, Hiroshi; Kurata, Noritaka*; Kobayashi, Nozomi*; Takase, Misao*; Makino, Risa; Ozu, Akira; Nakamura, Hironobu; Kurita, Tsutomu; et al.
56th Annual Meeting of the Institute of Nuclear Materials Management (INMM 2015), Vol.1, p.693 - 701, 2016/00
no abstracts in English
He Alternative Neutron Detectors (ASAS), 1; Design and fabrication of ASAS detectorOzu, Akira; Tobita, Hiroshi; Kureta, Masatoshi; Tanigawa, Masafumi; Mukai, Yasunobu; Nakamichi, Hideo; Nakamura, Hironobu; Kurita, Tsutomu; Seya, Michio
Kaku Busshitsu Kanri Gakkai (INMM) Nihon Shibu Dai-36-Kai Nenji Taikai Rombunshu (Internet), 9 Pages, 2015/12
Against the background of the serious shortage of He gas, the Japan Atomic Energy Agency (JAEA) has newly developed an alternative ZnS ceramic scintillation neutron detector for the safeguards, with the support of the government (MEXT). A demonstrator of plutonium inventory sample assay system (ASAS) has been also developed as an alternative HLNCC (High Level Neutron Coincidence Counter). The results from numerical simulations using Monte-Carlo code MCNPX showed that the fundamental performances of ASAS equipped with the 24 alternative neutron detectors, such as neutron detection efficiency and die-away time, equal to or higher than those of conventional HLNCC could be obtained. Here we present the inner mechanical structure of ASAS, together with the results of the simulating design.
He Alternative Neutron Detectors (ASAS), 2; Results of ASAS measurement testTanigawa, Masafumi; Mukai, Yasunobu; Kurita, Tsutomu; Makino, Risa; Nakamura, Hironobu; Tobita, Hiroshi; Ozu, Akira; Kureta, Masatoshi; Seya, Michio
Kaku Busshitsu Kanri Gakkai (INMM) Nihon Shibu Dai-36-Kai Nenji Taikai Rombunshu (Internet), 9 Pages, 2015/12
Against the background of the serious shortage of He gas, design and development of a new detector equipped ZnS/
B
O
ceramic scintillation neutron detectors in JAEA, with the support of the government (the Ministry of Education, Culture, Sports, Science & Technology). The design of the alternative He detector is referred from INVS (INVentory Sample assay system (HLNCC (High Level Neutron Coincidence Counter) type)) which is being used for the verification of MOX powder etc. and is named it as ASAS (Alternative Sample Assay System). In order to prove the Pu quantitative performance as an alternative technology, several measurement tests and comparison test with INVS were conducted using ASAS. In these tests, evaluation of fundamental performance (counting efficiency and die-away time) and uncertainty evaluations were implemented. As a result, although fundamental performance of ASAS was not achieved to the one of INVS, we could confirm that ASAS has almost the same Pu quantitative performance including measurement uncertainty as that of INVS.
Mukai, Yasunobu; Nakamura, Hironobu; Tanigawa, Masafumi; Nakamichi, Hideo; Umino, Yoshinori; Fujisaku, Sakae; Kimura, Takashi; Kurita, Tsutomu
Kaku Busshitsu Kanri Gakkai (INMM) Nihon Shibu Dai-36-Kai Nenji Taikai Rombunshu (Internet), 9 Pages, 2015/12
When the unauthorized removal of nuclear materials (NM) from glovebox (GB) by an insider happens, it needs to be detected and reported immediately. In this time, for utilization of the security counterplan, the feasibility of a new detection concept for the unauthorized removal was investigated with implementation of several experiments considering actual GB operation. In general, the detection method using radiation monitor is thought of easily. However, it is very difficult to distinguish between authorized NM movement during operation and the unauthorized removal. To solve this subject, JAEA focused on negative pressure monitoring of GB, and investigated a new detection concept combining the neutron and negative pressure monitoring. As a result of the experiments in small-scale GB, it was revealed that this new concept had the capability to detect the unauthorized removal and to alarm to central alarm station rapidly, and had the possibility to enhance the effectiveness of the current physical protection measures.
Nakamura, Hironobu; Tanigawa, Masafumi; Mukai, Yasunobu; Nakamichi, Hideo; Umino, Yoshinori; Fujisaku, Sakae; Kimura, Takashi; Kurita, Tsutomu
Proceedings of INMM 56th Annual Meeting (Internet), 8 Pages, 2015/07
In the MOX handling facilities, many types and amount of nuclear materials (NM) that are relatively easy to access are used in a GB. In order to prevent unauthorized removal of NM from the GB by an insider, based on the Japanese regulation which was referred from INFCIRC/225 Rev.5, the 2 person rule are being introduced at the area where NM handling GB are installed. As an example of usage of the security counterplan for the detection of unauthorized removal of NM, a new proposal of detection concept for the unauthorized removal by operators were investigated with implementation of several experiments considering actual GB operation. In general, it is considered that normal concept is to use radiation monitor ( or neutron) to detect the event by checking the variation of monitoring data. However, it is thought that distinguish between authorized NM movement during operation and the unauthorized removal (sample bag-out from GB) is very difficult. To solve this subject, JAEA studied and proposes a new concept about negative pressure monitoring in the GB in addition to the radiation monitoring. It is thought that the hybrid monitoring concept between pressure and radiation provides the detection alarm for it with central alarm station (CAS) accurately and rapidly with high integrity, and helps to complement current 2 person rule.
Tanigawa, Masafumi; Kato, Yoshiyuki; Kurita, Tsutomu; Kusano, keiichi*; Otaka, Akihiro*; Nakamichi, Hideo*
no journal, ,
no abstracts in English
Tanigawa, Masafumi; Kato, Yoshiyuki; Kurita, Tsutomu; Komatsuzaki, Mai*; Otaka, Akihiro*; Nakamichi, Hideo*
no journal, ,
no abstracts in English
Kato, Yoshiyuki; Tanigawa, Masafumi; Takahashi, Naoki; Kurita, Tsutomu
no journal, ,
Plutonium nitrate and uranyl nitrate mixed solution is co-converted to MOX powder by the microwave heating method developed by JAEA. The appropriate placement in the microwave oven of the specimen is very important to improve the energy-saving performance in this conversion process. However, much labor is required to perform the plutonium nitrate and uranyl nitrate mixed solution heating examination by the microwave and the electromagnetic field analysis in the microwave oven. Therefore an electrical characteristic carried out a heating examination using the similar nitric acid solution with plutonium nitrate and nitric acid uranyl solution. Furthermore, the electromagnetism properties in the oven tried an application by a height pattern theory used for an antenna circuit. The experimental results could almost be explained by the numerical analyses.
Takeda, Nobukazu; Noguchi, Yuto; Maruyama, Takahito; Inoue, Ryuichi; Komai, Masafumi; Kozaka, Hiroshi; Tanigawa, Hisashi; Kakudate, Satoshi
no journal, ,
In general, nuclear fusion device requires remote maintenance system to avoid human access because of -ray emitted from structural material, which is activated by neutron of fusion reaction. The remote maintenance system was first introduced in the Joint European Torus (JET) which was constructed in UK based on international cooperation in Europe. The JET used so-called "Boom type" remote handling system which introduces articulated arm from a port. The arm is supported from the port with canti-levered and therefore the capacity is relatively low: 300 kg in JET. On the contrary, the ITER uses different type of remote handling system. The JT-60SA, which is under construction in Japan, also considers remote maintenance. This paper describes outline of remote maintenance systems for the international fusion experimental reactor, ITER.
Tanigawa, Masafumi; Kato, Yoshiyuki; Isomae, Hidemi; Komatsuzaki, Mai*; Yoshino, Masanori*
no journal, ,
no abstracts in English
