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JAEA Reports

Waste liquid treatment for uranium liquid waste containing impurities

Sato, Yoshiyuki; Aono, Ryuji; Haraga, Tomoko; Ishimori, Kenichiro; Kameo, Yutaka

JAEA-Testing 2019-003, 20 Pages, 2019/12

JAEA-Testing-2019-003.pdf:2.08MB

In the Radioactive Waste Management Technology Section, the radioactive liquid waste generated in the test using natural uranium in the past has been stored based on the contents of permission. Although we decided to perform solidification treatment in order to reduce the risk in storage, no rational treatment method has been established so far. Therefore, we examined adsorption treatment of natural uranium using uranium adsorbent (Tannix), and finally stabilized treatment by cement solidification. The treatment methods and findings obtained for a series of operations in waste liquid treatment are summarized in this report for reference when treating similar liquid waste.

Journal Articles

Thermodynamic interpretation of uranium(IV/VI) solubility in the presence of $$alpha$$-isosaccharinic acid

Kobayashi, Taishi*; Sasaki, Takayuki*; Kitamura, Akira

Journal of Chemical Thermodynamics, 138, p.151 - 158, 2019/11

 Times Cited Count:0 Percentile:100(Thermodynamics)

The effect of $$alpha$$-isosaccharinic acid (ISA) on the solubility and redox of tetravalent and hexavalent uranium (U(IV), U(VI)) was investigated in the hydrogen ion concentration (pH$$_{c}$$) range of 6$$sim$$13 and at total ISA concentration ([ISA]$$_{rm tot}$$) = 10$$^{-4}$$$$sim$$10$$^{-1.2}$$ mol/dm$$^{3}$$. The dependence of U(IV) solubility on pH$$_{c}$$ and [ISA]$$_{rm tot}$$ suggested the existence of U(OH)$$_{4}$$(ISA)$$_{2}$$$$^{2-}$$ as a dominant species within the investigated pH$$_{c}$$ range of 6$$sim$$12. For the U(VI)-ISA system, UO$$_{2}$$(OH)$$_{3}$$(ISA)$$_{2}$$$$^{2-}$$ was suggested as a dominant species at pH$$_{c}$$ 7$$sim$$13. The formation constants of the U(IV)-ISA and U(VI)-ISA complexes were determined by least-squares fitting of the solubility data. The solubility of U(IV) and U(VI) in the presence of ISA and its effect on the redox behavior were thermodynamically interpreted based on the obtained constants.

Journal Articles

Uranium waste engineering research at the Ningyo-Toge Environmental Engineering Center of JAEA

Umezawa, Katsuhiro; Morimoto, Yasuyuki; Nakayama, Takuya; Nakagiri, Toshio

Proceedings of 27th International Conference on Nuclear Engineering (ICONE-27) (Internet), 6 Pages, 2019/05

In December 2016, the Ningyo-toge Environmental Engineering Center of Japan Atomic Energy Agency (JAEA Ningyo-toge) announced new concept of "Uranium and Environmental Research Platform". As part of the concept, uranium waste engineering research are now undergoing. The objective of the research is to establish the processing technology for safely and reasonable disposal of uranium waste. In particular, estimation of the amount of uranium and harmful substances and development of technologies to reduce their concentration in the waste to the permissive level for the disposal in shallow ground disposal are needed. We are now developing the technologies to reduce the concentration of uranium and harmful substances shown below. (1) Survey on uranium inventory. Uranium waste is now stored in 10-odd thousands of 200 L drums. We are surveying amount and chemical form of uranium in the drums. (2) Development of decontamination technology of metal and concrete waste. We are investigating decontamination methods for metals and concrete contaminated with uranium. (3) Development of technologies to remove, detoxify and fix the harmful substances. We are surveying the types and amounts of harmful substances in waste. In addition, we are investigating the method to remove, detoxify, and fix harmful substances. (4) Measurement technology of uranium radioactivity. We are investigating and examining ways to improve the quantitative accuracy of measurement and shorten the measurement time. (5) Development of uranium removal technology from sludge. We are investigating new processing method to remove uranium from sludge which is applicable for several kind of sludge. The results of these technological developments and environmental research will be reflected to "small-scale field test" and "disposal demonstration test" which are planned for demonstration of the uranium waste disposal technology.

JAEA Reports

Update of JAEA-TDB; Update of thermodynamic data for zirconium and those for isosaccahrinate, tentative selection of thermodynamic data for ternary M$$^{2+}$$-UO$$_{2}$$$$^{2+}$$-CO$$_{3}$$$$^{2-}$$ system and integration with JAEA's thermodynamic database for geochemical calculations

Kitamura, Akira

JAEA-Data/Code 2018-018, 103 Pages, 2019/03

JAEA-Data-Code-2018-018.pdf:5.66MB
JAEA-Data-Code-2018-018-appendix1(DVD-ROM).zip:0.14MB
JAEA-Data-Code-2018-018-appendix2(DVD-ROM).zip:0.15MB
JAEA-Data-Code-2018-018-appendix3(DVD-ROM).zip:0.19MB

The latest available thermodynamic data were critically reviewed and the selected values were included into the JAEA-TDB for performance assessment of geological disposal of high-level radioactive and TRU wastes. This critical review specifically addressed thermodynamic data for (1) a zirconium-hydroxide system through comparison of thermodynamic data selected by the Nuclear Energy Agency within the Organisation for Economic Co-operation and Development (OECD/NEA), (2) complexation of metal ions with isosaccharinic acid based on the latest review papers. Furthermore, the author performed (3) tentative selection of thermodynamic data on ternary complexes among alkaline-earth metal, uranyl and carbonate ions, and (4) integration with the latest version of JAEA's thermodynamic database for geochemical calculations. The internal consistency of the selected data was checked by the author. Text files of the updated and integrated thermodynamic database have been prepared for geochemical calculation programs of PHREEQC and Geochemist's Workbench.

Journal Articles

Magnetic and electrical properties of the ternary compound U$$_2$$Ir$$_3$$Si$$_5$$ with one-dimensional uranium zigzag chains

Li, D. X.*; Honda, Fuminori*; Miyake, Atsushi*; Homma, Yoshiya*; Haga, Yoshinori; Nakamura, Ai*; Shimizu, Yusei*; Maurya, A.*; Sato, Yoshiki*; Tokunaga, Masashi*; et al.

Physical Review B, 99(5), p.054408_1 - 054408_9, 2019/02

 Times Cited Count:0 Percentile:100(Materials Science, Multidisciplinary)

JAEA Reports

Calculations of Tritium Recoil Release from Li and U Impurities in Neutron Reflectors (Joint research)

Ishitsuka, Etsuo; Kenzhina, I.*; Okumura, Keisuke; Ho, H. Q.; Takemoto, Noriyuki; Chikhray, Y.*

JAEA-Technology 2018-010, 33 Pages, 2018/11

JAEA-Technology-2018-010.pdf:2.58MB

As a part of study on the mechanism of tritium release to the primary coolant in research and testing reactors, tritium recoil release rate from Li and U impurities in the neutron reflector made by beryllium, aluminum and graphite were calculated by PHITS code. On the other hand, the tritium production from Li and U impurities in beryllium neutron reflectors for JMTR and JRR-3M were calculated by MCNP6 and ORIGEN2 code. By using both results, the amount of recoiled tritium from beryllium neutron reflectors were estimated. It is clear that the amount of recoiled tritium from Li and U impurities in beryllium neutron reflectors are negligible, and 2 and 5 orders smaller than that from beryllium itself, respectively.

Journal Articles

Spectroscopic measurements of L X-rays with a TES microcalorimeter for a non-destructive assay of transuranium elements

Nakamura, Keisuke; Morishita, Yuki; Takasaki, Koji; Maehata, Keisuke*; Sugimoto, Tetsuya*; Kiguchi, Yu*; Iyomoto, Naoko*; Mitsuda, Kazuhisa*

Journal of Low Temperature Physics, 193(3-4), p.314 - 320, 2018/11

 Times Cited Count:0 Percentile:100(Physics, Applied)

Journal Articles

Retention of uranium in cement systems; Effects of cement degradation and complexing ligands

Ochs, M.*; Vriens, B.*; Tachi, Yukio

Progress in Nuclear Science and Technology (Internet), 5, p.208 - 212, 2018/11

The clean-up activities related to the accident at the Fukushima Nuclear Power Plant give rise to several types of wastes containing cementitious materials, such as concrete. Further, the use of cement-based barriers may be considered, due to their favorable and stable chemical properties, including their ability to sorb or incorporate radionuclides. Wastes from Fukushima are expected to contain substances that can have perturbing effects on retention, especially organic complexing substances, boron, and chloride salts. The present study focuses on a methodology for quantifying the retention behaviour of UVI) and U(IV) in cement materials of different degradation and in the presence of organics, boron, and salts on the basis of available literature information. A stepwise approach is proposed and illustrated for Kd setting for U(VI) and U(IV).

Journal Articles

Study on criticality in natural barrier for disposal of fuel debris from Fukushima Daiichi NPS

Shimada, Taro; Takubo, Kazuya*; Takeda, Seiji; Yamaguchi, Tetsuji

Progress in Nuclear Science and Technology (Internet), 5, p.183 - 187, 2018/11

After fuel debris is removed from the reactor containment vessel at Fukushima Daiichi NPS (1F) and collected in waste containers in the future, the waste containers will be disposed at a deep geological repository. The uranium inventory and uranium-235 ($$^{235}$$U) enrichment of the fuel debris are larger than those of high-level vitrified wastes which are produced from liquid waste during reprocessing of spent nuclear fuels. Therefore, there is a possibility not to be excluded that a criticality occurs in the geological media where the uranium precipitates at the far-field from the repository, after the uranium located in the repository is dissolved by groundwater. In this study, we calculated the quantity of uranium precipitated at the natural barrier, and studied dimension of uranium deposited in the natural barrier and carried out the criticality analysis.

Journal Articles

Magnetization study on the Ising ferromagnet URhGe with high-precision angle-resolved magnetic field near the hard axis

Nakamura, Shota*; Sakakibara, Toshiro*; Shimizu, Yusei*; Kittaka, Shunichiro*; Kono, Yohei*; Haga, Yoshinori; Pospisil, J.; Yamamoto, Etsuji

Progress in Nuclear Science and Technology (Internet), 5, p.123 - 127, 2018/11

Journal Articles

Anomalous Hall effect in a triangular-lattice antiferromagnet UNi$$_4$$B

Oyamada, Akira*; Inohara, Takao*; Yamamoto, Etsuji; Haga, Yoshinori

Progress in Nuclear Science and Technology (Internet), 5, p.128 - 131, 2018/11

Journal Articles

Crystal structure and magnetic properties of new ternary uranium compound U$$_3$$TiBi$$_9$$

Motoyama, Gaku*; Haga, Yoshinori; Yamaguchi, Akira*; Kawasaki, Ikuto*; Sumiyama, Akihiko*; Yamamura, Tomoo*

Progress in Nuclear Science and Technology (Internet), 5, p.157 - 160, 2018/11

Journal Articles

Continuous liquid-liquid extraction of uranium from uranium-containing wastewater using an organic phase-refining-type emulsion flow extractor

Nagano, Tetsushi; Naganawa, Hirochika; Suzuki, Hideya; Toshimitsu, Masaaki*; Mitamura, Hisayoshi*; Yanase, Nobuyuki*; Grambow, B.

Analytical Sciences, 34(9), p.1099 - 1102, 2018/09

 Times Cited Count:4 Percentile:49.45(Chemistry, Analytical)

A previously reported emulsion flow (EF) extraction system does not include a device for refining used solvent. Therefore, the processing of large quantities of wastewater by using the EF extractor alone could lead to the accumulation of wastewater components into the solvent and diminished extraction performance. In the present study, we have developed a solvent-washing-type EF system, which is equipped with a unit for washing used solvent to prevent accumulation, and successfully applied it for treating uranium-containing wastewater.

Journal Articles

Crystallographic, magnetic, thermal, and electric transport properties in UPtIn single crystal

Matsumoto, Yuji*; Haga, Yoshinori; Tateiwa, Naoyuki; Yamamoto, Etsuji; Fisk, Z.*

Journal of the Physical Society of Japan, 87(2), p.024706_1 - 024706_4, 2018/02

 Times Cited Count:0 Percentile:100(Physics, Multidisciplinary)

Journal Articles

Lead void reactivity worth in two critical assembly cores with differing uranium enrichments

Fukushima, Masahiro; Goda, J.*; Bounds, J.*; Cutler, T.*; Grove, T.*; Hutchinson, J.*; James, M.*; McKenzie, G.*; Sanchez, R.*; Oizumi, Akito; et al.

Nuclear Science and Engineering, 189, p.93 - 99, 2018/01

 Times Cited Count:3 Percentile:20.13(Nuclear Science & Technology)

To validate lead (Pb) nuclear cross sections, a series of integral experiments to measure lead void reactivity worths was conducted in a high-enriched uranium (HEU)/Pb system and a low enriched uranium (LEU)/Pb system using the Comet Critical Assembly at NCERC. The critical experiments were designed to provide complementary data sets having different sensitivities to scattering cross sections of lead. The larger amount of the $$^{238}$$U present in the LEU/Pb core increases the neutron importance above 1 MeV compared with the HEU/Pb core. Since removal of lead from the core shifts the neutron spectrum to the higher energy region, positive lead void reactivity worths were observed in the LEU/Pb core while negative values were observed in the HEU/Pb core. Experimental analyses for the lead void reactivity worths were performed with the Monte Carlo calculation code MCNP6.1 together with nuclear data libraries, JENDL 4.0 and ENDF/B VII.1. The calculation values were found to overestimate the experimental ones for the HEU/Pb core while being consistent for the LEU/Pb core.

Journal Articles

Effects of $$gamma$$-ray polarization in NRF-based nondestructive assay of nuclear materials

Omer, M.; Hajima, Ryoichi*; Shizuma, Toshiyuki*; Koizumi, Mitsuo

Proceedings of INMM 58th Annual Meeting (Internet), 7 Pages, 2017/07

Nuclear resonance fluorescence (NRF) is a process in which the electric and/or the magnetic dipole excitations of the nucleus take place. Since these excitations are unique signatures of each nucleus, the NRF provides a practical tool for a non-destructive detection and assay of nuclear materials. Using a polarized $$gamma$$-ray beam, distinguishing the nature of the excitation is straightforward. At a scattering angle of 90$$^{circ}$$, the electric dipole excitations are radiated normal to the polarization plane whereas the magnetic dipole excitations are radiated in the same plane as the incident beam polarization. By contrast, other $$gamma$$-ray interactions with the atom may exhibit different responses regarding the polarization of the incident beam. For example, the elastic scattering is expected to give approximately 60% lower yield in the direction of the incident beam polarization than the other direction. This fact significantly affects the sensitivity of the NRF technique because it is not possible to separate the NRF and the elastic scattering on the basis of the photon energy. We report the results of a photon scattering experiment on $$^{238}$$U using a 100% linearly polarized $$gamma$$-ray beam with an energy of 2.04 MeV. We demonstrate how the elastic scattering responds to the polarization of the incident beam. Accordingly, we are able to resolve the effects of the polarization of incident photon in an NRF measurement.

Journal Articles

Effect of pressure on magnetism of UIrGe

Pospisil, J.; Gochi, Jun*; Haga, Yoshinori; Honda, Fuminori*; Uwatoko, Yoshiya*; Tateiwa, Naoyuki; Kambe, Shinsaku; Nagasaki, Shoko*; Homma, Yoshiya*; Yamamoto, Etsuji

Journal of the Physical Society of Japan, 86(4), p.044709_1 - 044709_6, 2017/04

 Times Cited Count:5 Percentile:34.19(Physics, Multidisciplinary)

Journal Articles

Switching of magnetic ground states across the UIr$$_{1-x}$$Rh$$_x$$Ge alloy system

Pospisil, J.; Haga, Yoshinori; Kambe, Shinsaku; Tokunaga, Yo; Tateiwa, Naoyuki; Aoki, Dai*; Honda, Fuminori*; Nakamura, Ai*; Homma, Yoshiya*; Yamamoto, Etsuji; et al.

Physical Review B, 95(15), p.155138_1 - 155138_15, 2017/04

 Times Cited Count:9 Percentile:30.41(Materials Science, Multidisciplinary)

Journal Articles

Uranium particle identification with SEM-EDX for isotopic analysis by secondary ion mass spectrometry

Esaka, Fumitaka; Magara, Masaaki

Mass Spectrometry Letters, 7(2), p.41 - 44, 2016/06

Secondary ion mass spectrometry (SIMS) is a promising tool to measure isotope ratios of individual uranium particles in environmental samples for nuclear safeguards. However, the analysis requires prior identification of a small number of uranium particles that coexist with a large number of other particles without uranium. In the present study, this identification was performed by scanning electron microscopy -energy dispersive X-ray analysis with automated particle search mode. The analytical results for an environmental sample taken at a nuclear facility indicated that the observation of backscattered electron images with $$times$$ 1000 magnification was appropriate to efficiently identify uranium particles. Lower magnification (less than $$times$$ 500) made it difficult to detect smaller particles of approximately 1 $$mu$$m diameter.

JAEA Reports

Measurement of uranium spectrum using laser induced breakdown spectroscopy; High resolution spectroscopy (470-670 nm)

Akaoka, Katsuaki; Oba, Masaki; Miyabe, Masabumi; Otobe, Haruyoshi; Wakaida, Ikuo

JAEA-Research 2016-005, 40 Pages, 2016/05

JAEA-Research-2016-005.pdf:1.82MB

Laser Induced Breakdown Spectroscopy (LIBS) method is an attractive technique because real-time, in-situ and remote elemental analysis is possible without any sample preparation. The LIBS technique can be applied for analyzing elemental composition of samples under severe environments such as the estimation of impurities in the next generation nuclear fuel material containing minor actinide (MA) and the detection of fuel debris in the post-accident nuclear core reactor of TEPCO Fukushima Daiichi Nuclear Power Plant. For applying LIBS to the analysis of nuclear fuel materials, it is indispensable to identify the emission spectrum and its intensity on impurities intermingled within complex emission spectra of matrix elements such as uranium (U) and plutonium (Pu). In the present study, an echelle spectrometer with a resolving power of 50,000 was employed to identify spectra of natural uranium of wavelength ranging from 470 to 670 nm. The 173 atomic spectra and 119 ionic spectra can be identified. We have confirmed that the measured wavelength and oscillator strength of spectra are consistent with published values.

346 (Records 1-20 displayed on this page)