Investigation and evaluation of sorption and diffusion data for sedimentary rocks and cementitious materials (Report on NUMO-JAEA collaborative research in FY2016-2017) (Joint research)

Hamamoto, Takafumi*; Matsubara, Ryuta*; Shibutani, Sanae*; Suyama, Tadahiro*; Tachi, Yukio

JAEA-Data/Code 2017-014, 31 Pages, 2018/03

JAEA-Data-Code-2017-014.pdf:2.1MB
JAEA-Data-Code-2017-014-appendix(CD-ROM).zip:0.61MB

NUMO and JAEA have developed the methodology of post-closure safety assessment for the geological disposal. For this purpose, NUMO and JAEA have conducted a collaborative research project for developing the safety assessment methodology based on international state of the art knowledge. The present report focuses on investigation of sorption and diffusion data reported and their QA evaluation for updating sorption and diffusion database (SDB and DDB) as the collaborative research project between NUMO and JAEA. This report includes sorption and diffusion data for mainly sedimentary rocks and cement materials. As a result, 1,746 sorption data from 19 references and 593 diffusion data from 25 references were extracted and prepared in the datasheet of SDB and DDB.

Sorption behavior of thorium onto montmorillonite and illite

Iida, Yoshihisa; Barr, L.; Yamaguchi, Tetsuji; Hemmi, Ko

Genshiryoku Bakkuendo Kenkyu (CD-ROM), 23(1), p.3 - 8, 2016/06

http://doi.org/10.3327/jnuce.23.1_3

Thorium (Th)-229 is one of the important radionuclides for the performance assessment calculations for high-level radioactive waste repositories. The sorption behavior of Th onto montmorillonite and illite were investigated by batch sorption experiments. Experiments were carried out under variable pH and carbonate concentrations. The sorbability of montmorillonite was higher than that of illite. Distribution coefficients, (m kg), decreased with increased carbonate concentrations and showed the minimal value at around pH 10. The sorption behaviors of Th were analyzed by the non-electrostatic surface complex model with PHREEQC computer program. The model calculations were able to explain the experimental results reasonably well. The decreases of was likely due to the stabilization of aqueous species by hydroxo-carbonate complexations in the solutions.

Distribution coefficients of iodine and tin on granodiorite and tuffaceous sandstone specimens

Hemmi, Ko; Yamaguchi, Tetsuji; Iida, Yoshihisa

Genshiryoku Bakkuendo Kenkyu (CD-ROM), 22(1), p.3 - 10, 2015/06

https://doi.org/10.3327/jnuce.22.3

Iodine and tin are important elements in performance assessment of geological disposal of radioactive wastes. Sorption experiments of iodine were carried out under varying nitrate concentration with a range of 0 to 5 mol dm at neutral pH range in order to determine the distribution coefficient of iodine was zero or non-zero value. The experimental results with estimated statistical errors showed non-zero values for tuffaceous sandstone except for NaNO concentration 0.5 mol dm. Non-zero values were also obtained under NaNO concentrations higher than 0.5 mol dm for granodiorite. Sorption experiments of tin were carried out at high pH range in order to check whether the distribution coefficient of tin decreases significantly with pH as a result of formation of anionic hydrolysis species of tin. The distribution coefficients of tin on granodiorite decreased from 9.7910 m kg at pH10.4 to 2.4610 m kg at pH12.4. The distribution coefficient of tin on tuffaceous sandstone was about one order of magnitude higher (about 210 m kg) than that of granodiorite at pH around 12.4.

Evaluation of uncertainty associated with parameters for long-term safety assessments of geological disposal

Yamaguchi, Tetsuji; Minase, Naofumi; Iida, Yoshihisa; Tanaka, Tadao; Nakayama, Shinichi

JAERI-Conf 2005-007, p.150 - 155, 2005/08

https://jopss.jaea.go.jp/pdfdata/JAERI-Conf-2005-007.pdf

no abstracts in English

The Evaluation of graft-adsorbent for removal of uranium from waste sludge

Seko, Noriaki; Tamada, Masao; Yoshii, Fumio

Nihon Genshiryoku Gakkai Wabun Rombunshi, 3(4), p.340 - 345, 2004/12

https://doi.org/10.3327/taesj2002.3.340

Fibrous adsorbents having chelate agent such as amidoxime (AN/MAA-ad), iminodiacetic acid (IDA-ad), and phosphoric acid (HMPA-ad) were prepared by radiation-induced graft polymerization. AN/MAA-ad was synthesized by co-grafting of acrylonitrile and methacrylic acid. Then the introduced functional group of CN was converted to the amidoxime with chemical treatment. Grafting of glycidyl methacrylate and chemically introducing the IDA group synthesized IDA-ad. HMPA-ad was directly synthesized by grafting of phosphoric acid monomer. The densities of the chelate agency were 3.5 mol/kg for AN/MAA-ad, 2.0 mol/kg for IDA-ad and 2.0 mol/kg for HMPA-ad after the grafting time of 2, 1.5 and 8 hours, respectively. HMPA-ad had 200 times higher distribution coefficient for uranium than that of a commercial adsorbent (Diaion-PK216) at pH 0.5. The distribution coefficient for AN/MAA-ad became 500 times higher than that of Diaion-CR11 more than pH 8. These chelate adsorbents are promising materials for removal of uranium from acid or alkali treated waste sludge contaminated uranium.

Applicability of sorption data determined by laboratory experiments for evaluation of strontium-85 mobility in subsurface field

Tanaka, Tadao; Mukai, Masayuki; Li, Z.*; Li, S.*

JAERI-Conf 2003-010, p.142 - 149, 2003/09

https://jopss.jaea.go.jp/pdfdata/JAERI-Conf-2003-010.pdf

An environmental migration test of Sr-85 was carried out in natural unsaturated loess zone at the field test site of China Institute for Radiation Protection, China, and the migratory mobility of Sr was observed during 2 years. As laboratory experiments, the migration experiment of Sr by a column system and the sorption experiment of Sr by a batch system were carried out by using the loess taken from the field test site. We discussed about applicability of sorption data determined from the laboratory experiments to evaluating the Sr migration behavior investigated at the field test site. The Sr migration behavior at the field test site could be expressed by the equilibrium sorption model using distribution coefficients determined from the laboratory experiments. This supports that the valid distribution coefficient for the evaluation of Sr migration in natural environment is predicted from the laboratory experiments.

Migration behavior of stable and radioactive strontium in natural aquifer

Tanaka, Tadao; Mukai, Masayuki; Maeda, Toshikatsu; Munakata, Masahiro; Matsumoto, Junko; Ogawa, Hiromichi; Bamba, Tsunetaka*; Wang, Z.*; Yang, Y.*; Zhao, Y.*

Proceedings of International Symposium on Radioecology and Environmental Dosimetry, p.179 - 184, 2003/00

Migration behaviors of stable strontium element and radioactive nuclide strontium 90 in natural aquifer were studied by a field test, which was performed in the aquifer loess zone at 30 m under the ground surface of the field test site of China Institute for Radiation Protection. The migration behavior of stable strontium was a little different from that of Sr. The difference was evaluated by applying the distribution coefficient considering Sr and coexistent ion concentrations. Migration behavior of radionuclide in natural environment has been generally demonstrated on field tests without radioactive tracers and/or large-scale column tests with radioactive tracers. Such tests seem to be valuable to improve reliability of the migratory evaluation.

The Sorption database of radionuclides for cementitious materials

Kato, Hiroshige*; Mine, Tatsuya*; Mihara, Morihiro; Oi, Takao; Honda, Akira

JNC TN8400 2001-029, 63 Pages, 2002/01

JNC-TN8400-2001-029.pdf:1.81MB

Cementitious materials will be used for the TRU waste repository as a component of engineered barrier system. The distribution coefficients which represent the retardation of radionuclides migration for the cementitious materials would be one of the important parameter for the safety assessment. The much information of radionuclide sorption onto the cementitious materials has been accumulated through the study in the world. Therefore it is necessary to compile the information and Kd of the radionuclides reported in previous studies. In this report, the Kd of the important radionuclides, such as C, Ni, Se, Sr, Zr, Nb, Mo, Tc, Sn, I, Cs, Sm, Pb, Ra, Ac, Th, Pa, U, Np, Pu, Am, Cm, for the cementitious materials were compiled as the Sorption Database (SDB). For radionuclides to be sensitive to the redox potential, e.g. Se, Tc, Pa, U, Pu and Np, some Kds measured under the controlled atmosphere had been reported, and few Kds measured under the controlled redox potential had been reported. For Se, Mo, Sm, Cm and Ac, the distribution coefficients had not been reported, therefore distribution coefficients of Se and Mo for OPC (Ordinary Portland Cement) pastes were measured by batch sorption experiments and these data were added into the SDB.

Measurement of distribution coefficients for uranium series radionuclides under shallow land environment condition, 1

Ishii, Tomoaki*; Inagawa, Satoshi*; Gunji, Yasuyoshi*; Sakamoto, Yoshiaki; Takebe, Shinichi; Ogawa, Hiromichi; Sasaki, Tomozo*

Genshiryoku Bakkuendo Kenkyu, 8(1), p.55 - 64, 2001/09

http://ci.nii.ac.jp/naid/40007277676

Distribution coefficients of Uranium series nuclide(Pb,Ra,Ac,Th,Pa and U) were obtained under aerated zone environment and aquifer environment, for the safety evaluation of shallow underground disposal of uranium bearing waste. The distribution coefficients of them on 4 kinds of soil such as the loam in the rain water as for aerated zone environment and on 3 kinds of soil and rock such as the sand in groundwater as for aquifer environment have been measured by batch method. The distribution coefficients in aerated zone environment were one or two orders in magnitude higher than that in aquifer environment, except Ac. And, there was approximately the linear correlation on the relationship between cation exchange capacity and specific surface area, which are representative physical property of the soil, and distribution coefficient of lead, radium and protactinium.

Discussion of uncertainties associated with parameters of biosphere model for safety assessment of geologieal disposal through sensitivity analysis

Kato, Tomoko; ; Suzuki, Yuji*;

JNC TN8400 2001-014, 212 Pages, 2001/03

JNC-TN8400-2001-014.pdf:19.25MB

Reference Biospheres are regarded as tools which can be used for making reasonable estimates of radiological impacts for the purposes of safety assessment of geological disposal. Moreover, those are available for reducing the uncertainties based on future human environments and lifestyles. On the other hand, it is recognised that the parameter values have some uncertainties derived from experimental or sampling errors. It is possible to estimate the impacts of these uncertainties throughout the model by sensitivity analysis. Thus for this study, to evaluate the impact of the variation of migration conditions and exposure pathways, we changed some of migration and exposure parameters in turn, which were used in the compartment model where the geosphere-biosphere interface is a river in a plain.