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JAEA Reports

Study on the evaluation method to determine the radioactivity concentration waste generated from post-irradiation examination facilities

Hoshino, Yuzuru; Sakamoto, Yoshiaki; Muroi, Masayuki*; Mukai, Satoru*

JAEA-Technology 2015-015, 96 Pages, 2015/07

JAEA-Technology-2015-015.pdf:20.34MB

In order to dispose of the radioactive waste which generates from post-irradiation examination (PIE) facilities, the common evaluation method of radioactivity in wastes from PIE should be established by the actual data such as radioactivity values and the theoretical calculation. In this study, the radioactivity concentrations of 17 nuclides (H-3, C-14, Co-60, Ni-63, Sr-90, Tc-99, Cs-137, Eu-154, U-234, U-235, U-238, Pu-238, Pu-239, Pu-240, Pu-241, Am-241, Cm-244) in combustible wastes stored in NUCLEAR DEVELOPMENT CORPORATION were measured from 3 samples and the radioactivity was calculated by ORIGEN-2 based on initial contents and operation record of the spent fuel. From the comparison of the obtained data by the radiological measurement with the calculated values, the subject to be solved for establishment of the radioactivity evaluation method for PIE was extracted.

Journal Articles

Verification tests on nondestructive assay for $$^{238}$$U content in uranium-contaminated waste drums using $$gamma$$ method

Yokoyama, Kaoru; Sugitsue, Noritake; Muroi, Masayuki*; Suzuki, Yasuo*

Radioisotopes, 62(1), p.1 - 17, 2013/01

Radioactive waste generated from nuclear fuel facilities must have the acceptance criterion of disposal. Although the $$gamma$$ ray measurement technique is expected as the measurement technique, the correction for the influences of the heterogeneous waste distribution was needed. Therefore, the computational technique using the $$gamma$$ ray of two energies emitted from $$^{238}$$U progeny nuclide ($$^{rm 234m}$$Pa) was developed, and verified the validity with simulated waste. As a result, the relative error was less than 20%, and detection limit was 1.2 Bq/g.

JAEA Reports

Measurements of Distribution Coefficient for Sn, Pb, Th on Sand Stone and Tuff in Saline Type Groundwater

Nakazawa, Toshiyuki*; Okada, Kenichi*; Muroi, Masayuki*; Shibata, Masahiro; Suyama, Tadahiro*; Sasamoto, Hiroshi

JNC TN8400 2003-039, 44 Pages, 2004/02

JNC-TN8400-2003-039.pdf:2.91MB

We carried out the batch sorption experiments for Sn, Pb and Th in saline type groundwater to obtain the distribution coefficient (Kd) data that were lack in the JNC sorption database. As the results, the following data were obtained. Sn: in artificial sea water, Kd=1 m3/kg on sand stone, Pb: in artificial sea water, Kd=2 m3/kg on sand stone and Kd=4-10 m3/kg on tuff, Th: in artificial sea water, Kd=1-8 m3/kg on sand stone, in artificial sea water with high carbonate concentration, Kd=0 m3/kg on sand stone.

JAEA Reports

Study on solubility and leaching property of Iodine-129 waste-forms for geological disposal

Ueda, Shinzo*; *; *; Muroi, Masayuki*; *; Izumi, Jun*; *

JNC TJ8400 2001-025, 125 Pages, 2001/03

JNC-TJ8400-2001-025.pdf:8.46MB

As concern the study on the property of Iodine-129 waste-forms, the solubilities of iodine-sodalite and tourmaline and leachabilities of hidroxy-apatite and fluoro-apatite were measured last year. The results in this year are summarized as follows. (1)Solubility and Leachability of lodine-sodalite were measured under the condition of Leachabilities and solubilities of the synthesized iodine-sodalite were measured by means of a long-term leach test in the solution with chloride ions and high pH (12.5). The measured solubilities were within a range of 10$$^{-5}$$ - 10$$^{-4}$$ M. It showed a tendency to increase with increasing temperature. The lieachabilities showed a tendency to decrease as time passed, and were within a range of 10$$^{-9}$$ - 10$$^{-8}$$ g/cm$$^{2}$$/d(10$$^{-6}$$ - 10$$^{-5}$$ m/y). After the leach test, the solid phases were analyzed and the alternation was not observed. It was confirmed by the experiments that the sodalite waste form had a certain capability to contain iodine even though the chloride ion existence. (2)Leaching property of high density apatite sample The following results were obtained by the manufacture examination of high density apatite sample and leaching experiments; (a)As a manufacture technology for apatite molding body, Plasma-hotpress technology was applied. To the porosity which aims 5%, the porosity of hydroxyapatite and fluoroapatite was under 2%. (b)Ca and P leaching concentration from hydroxyapatite reached 10$$^{-6}$$ M order, which was same order solubility estimated by PHREEQE code. From this test results, it was indicated that apatite material has a possibility for a waste of low-Leachability and high density performance.

JAEA Reports

Study on development of a geological disposal technology integration system

Ishihara, Yoshinao*; Matsuoka, Fushiki*; Sagawa, Hiroshi*; Kawahara, Kenichi*; Kataoka, Shinichi*; Shinohara, Yoshinori*; Muroi, Masayuki*; Tsuchiya, Makoto*; Tsujimoto, Keiichi*; Ohashi, Toyo*

JNC TJ8400 2001-011, 259 Pages, 2001/03

JNC-TJ8400-2001-011.pdf:0.99MB

In this study, the basic design study on integrated computer system has been carried out in order to develop the integrated methodologies for future research and development activities of geological disposal system. The key conclusions are summarized as follows: (1) As the result of the investigation of work items and associated flow of information (data) between items in the second progress report by JNC, the interaction matrix and work flow chart have been identified in order to specify the basic configuration of the integrated computer system. In addition, the model chain and the structure of data relation between the repository design study and safety assessment study have been summarized. (2)We organized and examined the system factor and the information process flow in the design, safety analysis, and geological environment study based on the 2000 Report by JNC. Then we analyzed the workflow of geological disposal business when a specific site for a repository is fixed to obtain the system factor and the information process flow. We consider the fracture/porous media, site location (land/under the sea), and long-term stability of the crust (upheaval/sink) as the key factors in examining the workflow of geological disposal business. Then we organized the information change between the design and other study in geological disposal based on the 2000 Report by JNC. We examined the ideal workflow in which the design, safety analysis, and geologic environment study of geological disposal are closely coupled. We examined the scientific and technical base of the knowledge base (the system factor and the information process flow) which is derived from the above to construct the hierarchical structure of the knowledge base for geological disposal. (3)As the result of the interaction matrix and work flow chart for the R&D activities, the conceptual design and the function diagram on the integrated computer system has been proposed. (4)We examined the plan to ...

JAEA Reports

Modelling of the interaction of bentonite with hyperalkaline fluids

Muroi, Masayuki*

JNC TJ8400 2000-042, 127 Pages, 2000/02

JNC-TJ8400-2000-042.pdf:3.26MB

Hyperalkaline pore water of cementitious material used in TRU waste repository would react with bentonite and cause the increased porosity and the loss of the swelling and sorption ability. This work is a modelling study on bentonite-cement pore water. The possible extent of reaction between bentonite and cement pore water was simulated using the PRECIP reaction-transport code. Three cement pore fluid compositions (leachates 1,2 and 3) were reacted with a 1-D, 1m flowpath of bentonite (+ sand) at 25 and 70$$^{circ}$$C. Key minerals were allowed to dissolve and precipitate using kinetic reaction mechanism. Leachate 1 was the most aggressive fluid (highest pH, Na and K), and leachate 3 (1owest pH, Na and Ca) the least aggressive. Simulation with leachate 1 showed total removal of primary bentonite minerals up to 60 cm from the contact with cement after $$sim$$1000 years. The maximum porosity increase observed was in leachate 1(up to 80-90%) over a narrow zone 1-2 cm. Simulations with all fluids showed total filling of pore with CSH minerals in a zone very close to the interface with the cement, whereas zeolites and sheet silicates formed far away. For a given leachate composition, there was little difference in the profiles at the two temperatures studied. It was suggested that bentonite alteration was not sensitive to the kinetic parameters over the conditions studied. The conceptual model chosen for the modelling study assumed that there was an unlimited amount of cement pore fluid available for reaction with bentonite so that the results of the simulations represent a conservative (pessimistic) estimate. There were a number of uncertainties associated with the modelling which relate to assumptions concerning: the kinetic mechanisms for dissolution and growth of minerals at elevated pH; evolving surface areas of minerals with time; thermodynamic data for CSH minerals, zeolites and aqueous species at high pH; the synergy between changing porosity and fluid ...

JAEA Reports

Modelling of the interaction of bentonite with hyperalkaline fluids

Muroi, Masayuki*

JNC TJ8400 2000-041, 11 Pages, 2000/02

JNC-TJ8400-2000-041.pdf:0.39MB

Hyperalkaline pore water of cementitious material used in TRU waste repository would react with bentonite and cause the increased porosity and the loss of the swelling and sorption ability. This work is a modelling study on bentonite-cement pore water. The possible extent of reaction between bentonite and cement pore water was simulated using the PRECIP reaction-transport code. Three cement pore fluid compositions (leachates 1,2 and 3) were reacted with a 1-D, 1m flowpath of bentonite (+ sand) at 25 and 70$$^{circ}$$C. Key minerals were allowed to dissolve and precipitate using kinetic reaction mechanism. Leachate 1 was the most aggressive fluid (highest pH, Na and K), and leachate 3 (lowest pH, Na and Ca) the least aggressive. Simulation with leachate 1 showed total removal of primary bentonite minerals up to 60 cm from the contact with cement after $$sim$$1000 years. The maximum porosity increase observed was in leachate 1(up to 80-90%) over a narrow zone 1-2 cm. Simulations with all fluids showed total filling of pore with CSH minerals in a zone very close to the interface with the cement, whereas zeolites and sheet silicates formed far away. For a given leachate composition, there was little difference in the profiles at the two temperatures studied. It was suggested that bentonite alteration was not sensitive to the kinetic parameters over the conditions studied. The conceptual model chosen for the modelling study assumed that there was an unlimited amount of cement pore fluid available for reaction with bentonite so that the results of the simulations represent a conservative (pessimistic) estimate.There were a number of uncertainties associated with the modelling which relate to assumptions concerning: the kinetic mechanisms for dissolution and growth of minerals at elevated pH; evolving surface areas of minerals with time; thermodynamic data for CSH minerals, zeolites and aqueous species at high pH; the synergy between changing porosity and fluid ...

JAEA Reports

None

Muroi, Masayuki*

PNC TJ1211 95-005, 244 Pages, 1995/02

PNC-TJ1211-95-005.pdf:7.17MB

1) P. Fletcher, G. Sposito, The Chemical Modelling of Clay/Electrolyte Interactionsor Montmorillonite, The Mineralogical Society, 24, 375-391 (1989) 2) H. Wanner, Moding Interaction of Deep Groundwaters with Bentonite and Radio nuclide Speciation, Nuear Technology, 9, 338-347 (1987) 3) H. Wanner, The NEA Thermochemical Data Base Prect, Radiochimica Acta 44/45, 325-239 (1988) 4)H. Wanner, Y. Albinsson, O. Karannla, E. Wieland, P. Wersin, L. Charlet, The Acid/Base Chemistry of Montmorillonite, Radchimica Acta 66/67, 157-162 (1994) 5) B. Allard, Sorption of actinides in granitic ck, KBS Report, 82-21 (1982) 6) H. Wanner, P. Wersin, N. Sierro, Thermodynamic modeing of bentonite-ground-water interaction and implications for near field chemistry a repository for spent fuel, KBS Report, 92-37 (1992) 7) H. Wanner, Y. Albinsson, Wieland, Project Caesium-An ion exchange model for the prediction of distribution cfficients of caesium in bentonite, KBS Report, 94-10 (1994) 8) E. Wieland, H

JAEA Reports

None

*; Maekawa, Kazuhiko*; Muroi, Masayuki*

PNC TJ4211 88-009, 242 Pages, 1988/12

PNC-TJ4211-88-009.pdf:16.83MB

None

JAEA Reports

None

Muroi, Masayuki*; *; *

PNC TJ4211 88-003VOL2, 67 Pages, 1988/03

PNC-TJ4211-88-003VOL2.pdf:10.01MB

None

Oral presentation

The Sorption of ISA on OPC paste

Nakazawa, Toshiyuki*; Muroi, Masayuki*; Honda, Akira

no journal, , 

no abstracts in English

Oral presentation

Development of the volume reduction treatment system of radioactive waste by the ultra-high frequency induction furnace, 4; Outline of the demonstration system

Yamaguchi, Hiromi; Miyamoto, Yasuaki; Sakakibara, Tetsuro; Hanamoto, Yukio; Aoyama, Yoshio; Sasaki, Nao*; Nishikawa, Tsutomu*; Murata, Minoru*; Muroi, Masayuki*; Park, J.*; et al.

no journal, , 

no abstracts in English

Oral presentation

Development of the volume reduction treatment system of radioactive waste by the ultra-high frequency induction furnace,5; Demonstration experiment, Melting performance verification

Yamaguchi, Hiromi; Miyamoto, Yasuaki; Sakakibara, Tetsuro; Hanamoto, Yukio; Aoyama, Yoshio; Sasaki, Nao*; Nishikawa, Tsutomu*; Murata, Minoru*; Muroi, Masayuki*; Park, J.*; et al.

no journal, , 

no abstracts in English

Oral presentation

Development of the volume reduction treatment system of radioactive waste by the ultra-high frequency induction furnace,6; Demonstration experiment, Non-radioactive tracer experiment

Aoyama, Yoshio; Yamaguchi, Hiromi; Miyamoto, Yasuaki; Sakakibara, Tetsuro; Hanamoto, Yukio; Sasaki, Nao*; Nishikawa, Tsutomu*; Murata, Minoru*; Muroi, Masayuki*; Park, J.*; et al.

no journal, , 

no abstracts in English

Oral presentation

Measurement technology of uranium quantity in radioactive waste, 3; Validation by numerical simulation and experiment

Zaima, Naoki; Sugitsue, Noritake; Takahashi, Nobuo; Yokoyama, Kaoru; Suzuki, Yasuo*; Muroi, Masayuki*

no journal, , 

no abstracts in English

Oral presentation

Measurement technology of uranium quantity in radioactive waste, 2; Development of mathematical scheme

Yokoyama, Kaoru; Zaima, Naoki; Takahashi, Nobuo; Sugitsue, Noritake; Suzuki, Yasuo*; Muroi, Masayuki*

no journal, , 

We have developed a new analysis method on measuring radioactivity of uranium ($$^{238}$$U) filled in waste drums using passive $$gamma$$ ray measurement. We proposed a new evaluation function which gives a unique relation between source positions and $$gamma$$ ray count rate.

Oral presentation

Measurement technology of uranium quantity in radioactive waste, 2; 3D measurement technique for make density uniform

Yokoyama, Kaoru; Zaima, Naoki; Takahashi, Nobuo; Sugitsue, Noritake; Suzuki, Yasuo*; Muroi, Masayuki*

no journal, , 

For determining radioactivity ($$^{238}$$U) of waste drums using $$gamma$$ ray measurement, we derived the geometric mean of measurements at various positions on spherical surface surrounding the waste drum to create the approximately homogeneous waste density.

Oral presentation

Measurement technology of uranium quantity in radioactive waste, 1; Feasibility study for measurement method of uranium quantity in radioactive waste with complexity and high density

Sugitsue, Noritake; Yokoyama, Kaoru; Zaima, Naoki; Takahashi, Nobuo; Suzuki, Yasuo*; Muroi, Masayuki*

no journal, , 

A simple evaluation of the coverage of the computing model was done. The density of waste and the radiation source distribution were calculated as a parameter. As a result, It has been understood that the application of the computing model is difficult in the ingot of the metal including the uranium.

Oral presentation

Measurement technology of uranium quantity in uranium waste, 3; Evaluation of relative error and detection limit using simulated waste

Yokoyama, Kaoru; Sugitsue, Noritake; Suzuki, Yasuo*; Muroi, Masayuki*; Nakatsuka, Yoshiaki; Ishii, Kazuto*

no journal, , 

The computational technique using the $$gamma$$ ray of two energies emitted from $$^{238}$$U progeny nuclide ($$^{rm 234m}$$Pa) was developed to determine uranium quantity in heterogeneous waste. In this study, the relative error and detection limit evaluation results using the simulated wastes are reported.

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