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Research Papers

Effects of Supersaturated Silicic Acid Concentration on Deposition Rate Around Geological Disposal System

[+] Author and Article Information
Tsuyoshi Sasagawa

Department of Quantum Science and Energy
Engineering,
Graduate School of Engineering,
Tohoku University,
Aramaki-Aza-Aoba 6-6-01-2, Aoba-ku,
Sendai 980-8579, Japan
e-mail: sasagawa314@michiru.qse.tohoku.ac.jp

Taiji Chida

Department of Quantum Science and
Energy Engineering,
Graduate School of Engineering,
Tohoku University,
Aramaki-Aza-Aoba 6-6-01-2,
Aoba-ku, Sendai 980-8579, Japan
e-mail: taiji.chida@qse.tohoku.ac.jp

Yuichi Niibori

Department of Quantum Science and
Energy Engineering,
Graduate School of Engineering,
Tohoku University,
Aramaki-Aza-Aoba 6-6-01-2, Aoba-ku,
Sendai 980-8579, Japan
e-mail: yuichi.niibori@qse.tohoku.ac.jp

1Corresponding author.

Manuscript received September 5, 2015; final manuscript received June 20, 2017; published online July 31, 2017. Assoc. Editor: Brian Ikeda.

ASME J of Nuclear Rad Sci 3(4), 041010 (Jul 31, 2017) (6 pages) Paper No: NERS-15-1189; doi: 10.1115/1.4037163 History: Received September 05, 2015; Revised June 20, 2017

Cementitious materials for the construction of a geological repository of radioactive waste alter the pH of groundwater to a highly alkaline condition (pH ≈ 13). While this alkaline groundwater dissolves silicate minerals, the soluble silicic acid polymerizes or deposits on the surface of rock with the decrease in pH by mixing with the surrounding groundwater (pH = 8). In particular, the deposition of silicic acid leads to a clogging effect in flow-paths, which retards the migration of radionuclides. This study estimated the clogging of silicic acid in flow-paths with the one-dimensional advection–dispersion model considering the deposition rate constants evaluated in our previous study. As some of the most important parameters, these estimations focused on the initial supersaturated concentration of silicic acid and the density of deposited minerals. As a result, the aperture of flow-paths (initial width: 0.1 mm, flow-rate: 5 m/y, initial supersaturated concentration of silicic acid: 0.01, 0.1 and 1.0 mM) was almost clogged within about 200 y by the deposition of silicic acid. The period for the clogging became shorter under the conditions of higher initial supersaturated concentration and lower density of deposited minerals. In other words, the use of cementitious materials for constructing the repository might produce a retardation effect of radionuclide migration by the deposition/clogging processes of the supersaturated silicic acid.

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References

JNC and FEPC, 2005, “ Second Progress Report on Research and Development for TRU Waste Disposal in Japan,” Japan Nuclear Cycle Development Organization Institute and The Federation of Electric Power Companies of Japan, Tokyo, Japan, Report No. JNC-TY1400-2005-013. https://www.jaea.go.jp/04/be/documents/doc_02.html
Mäder, U. K. , Fierz, T. , Frieg, B. , Eikenberg, J. , Rüthi, M. , Albinsson, Y. , Möri, A. , Ekberg, S. , and Stille, P. , 2006, “ Interaction of Hyperalkaline Fluid With Fractured Rock: Field and Laboratory Experiments of the HPF Project (Grimsel Test Site, Switzerland),” J. Geochem. Explor., 90(1–2), pp. 68–94. [CrossRef]
Niibori, Y. , Usui, H. , and Chida, T. , 2015, “ Double Porosity Model to Describe Both Permeability Change and Dissolution Processes,” Mech. Eng. J., 2(5), p. 15-00210.
Soler, J. M. , and Mäder, U. K. , 2010, “ Cement-Rock Interaction: Infiltration of a High-pH Solution Into a Fractured Granite Core,” Geol. Acta, 8(3), pp. 221–233.
Iler, R. K. , 1979, The Chemistry of Silica—Solubility, Polymerization, Colloid and Surface Properties, and Biochemistry, Wiley, New York.
Steefel, C. I. , and Lichtner, P. C. , 1994, “ Diffusion and Reaction in Rock Matrix Bordering a Hyperalkaline Fluid-Filled Fracture,” Geochim. Cosmochim. Acta, 58(17), pp. 3595–3612. [CrossRef]
Niibori, Y. , Kasuga, Y. , Kokubun, H. , and Mimura, H. , 2009, “ Dependence of the Dynamic Behavior of Supersaturated Silicic Acid on the Surface Area of the Solid Phase,” Mater. Res. Soc. Symp. Proc., 1124, pp. 319–324.
JNC, 1999, “ H12: Project to Establish the Scientific and Technical Basis for HLW Disposal in Japan,” Supporting Report I, Geological Environment in Japan, Japan Nuclear Cycle Development Institute, Ibaraki, Japan, Report No. JNC-TN1400 99-021. https://www.jaea.go.jp/04/tisou/english/report/H12_sr1.html
Tamura, N. , Niibori, Y. , Iijima, K. , and Mimura, H. , 2010, “ Dynamic Behavior of Silicic Acid in the Co-Presence of the Solid Phase and Ca Ions,” Waste Management Conference (WM), Phoenix, AZ, Mar. 7–11, Paper No. 10120. http://www.wmsym.org/archives/2010/pdfs/10120.pdf
Chigira, M. , 1991, “ Sealing of Rock Fractures Around HLW Repositories—Part 1: A New Hydrothermal Fracture Flow Apparatus and Its Preliminary Application to Self-Sealing by Silica,” Central Research Institute of Electric Power Industry, Tokyo, Japan, Report No. U91031 (in Japanese).
Chigira, M. , 1993, “ Sealing of Rock Fractures Around HLW Repositories—Part 2: Silica Precipitation Behavior in Flow Fields,” Central Research Institute of Electric Power Industry, Tokyo, Japan, Report No. U92050 (in Japanese).
Chigira, M. , 1996, “ Sealing of Rock Fractures Around HLW Repositories—Part 3: Silica Precipitation Rate, Colloidal Formation, and Pore Closure,” Central Research Institute of Electric Power Industry, Tokyo, Japan, Report No. U95053 (in Japanese).
Niibori, Y. , Iijima, K. , Tamura, N. , and Mimura, H. , 2012, “ A Calculation of Spatial Range of Colloidal Silicic Acid Deposited Downstream From the Alkali Front,” J. Power Energy Syst., 6(2), pp. 140–150. [CrossRef]
Niibori, Y. , Kasuga, Y. , Yoshikawa, H. , Tanaka, K. , Tochiyama, O. , and Mimura, H. , 2006, “ An Experimental Approach on the Effect of Rock Alteration on Sorption Behavior,” Mater. Res. Soc. Symp. Proc., 932, pp. 951–958. https://doi.org/10.1557/PROC-932-15.1
Sasagawa, T. , Chida, T. , Niibori, Y. , and Mimura, H. , 2015, “ Effects of pH on Deposition Rate of Supersaturated Silicic Acid Around Geological Disposal System,” Waste Management Conference (WM), Phoenix, AZ, Mar. 15–19, Paper No. 15245.
Berner, R. A. , 1971, Principles of Chemical Sedimentology, McGraw-Hill, New York.
Lindsay, W. L. , 1979, Chemical Equilibria in Soils, Wiley, New York.
Nakagawa, K. , 2008, “ Microscopic and Macroscopic Dispersions in Convection-Dispersion Processes,” J. Groundwater Hydrol., 50(3), pp. 179–186 (in Japanese). [CrossRef]
Unger, K. K. , 1979, Porous Silica, Elsevier, Amsterdam, The Netherlands.
Bergna, H. E. , and Roberts, W. O. , 2005, Colloidal Silica: Fundamentals and Applications, CRC Press, Boca Raton, FL.

Figures

Grahic Jump Location
Fig. 1

One-dimensional parallel flat board

Grahic Jump Location
Fig. 2

Schematic of the one-dimensional mass balance

Grahic Jump Location
Fig. 3

Dependencies of initial supersaturated concentration on the deposition of silicic acid: (a) 2 mM, (b) 4 mM, (c) 6 mM, and (d) 8 mM, amount of solid phase: 1.0 g

Grahic Jump Location
Fig. 4

Calculation of deposition rate-constant k (m/s): (a) the calculation of rini (1/s) and (b) the relation of rini and specific surface area A (1/s))

Grahic Jump Location
Fig. 5

The clogging behavior of flow path: (a) α-quartz, k = 3.67 × 10−11 m/s, (b) α-quartz, k = 2.10 × 10−10 m/s, (c) amorphous silica, k = 3.67 × 10−11 m/s, (d) amorphous silica, k = 2.10 × 10−10 m/s, (e) silicic acid, k = 3.67 × 10−11 m/s, and (f) silicic acid, k = 2.10 × 10−10 m/s

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