Hostname: page-component-76fb5796d-skm99 Total loading time: 0 Render date: 2024-04-27T16:48:38.964Z Has data issue: false hasContentIssue false
  • English
  • Français

Ice-Bentonite Powder Mixing Method to Improve the Homogeneity of Compacted Bentonite in An Initial Sample Preparation Stage

Published online by Cambridge University Press:  01 January 2024

Yu Peng ,
Huyuan Zhang ,
Bingzhuo Yang ,
Xuewen Wang ,
Xianxian Shao  and
Ping Liu
Yu Peng
Affiliation:
Key Laboratory of Mechanics on Disaster and Environment in Western China (Lanzhou University), Ministry of Education, Lanzhou 730000, China
Huyuan Zhang*
Affiliation:
Key Laboratory of Mechanics on Disaster and Environment in Western China (Lanzhou University), Ministry of Education, Lanzhou 730000, China
Bingzhuo Yang
Affiliation:
Key Laboratory of Mechanics on Disaster and Environment in Western China (Lanzhou University), Ministry of Education, Lanzhou 730000, China
Xuewen Wang
Affiliation:
Key Laboratory of Mechanics on Disaster and Environment in Western China (Lanzhou University), Ministry of Education, Lanzhou 730000, China
Xianxian Shao
Affiliation:
Key Laboratory of Mechanics on Disaster and Environment in Western China (Lanzhou University), Ministry of Education, Lanzhou 730000, China
Ping Liu
Affiliation:
Key Laboratory of Mechanics on Disaster and Environment in Western China (Lanzhou University), Ministry of Education, Lanzhou 730000, China
*
*E-mail address of corresponding author: zhanghuyuan@lzu.edu.cn
Get access Rights & Permissions [Opens in a new window]

Abstract

Bentonite is considered as an ideal buffer/backfill material for preparing an engineering barrier for high-level radioactive waste (HLW) disposal. During initial sample preparation, the tendency of wet bentonite powder to gather into large agglomerates and the water to be spread unevenly in the traditional water content adjustment process decreases the homogeneity of compacted bentonite. The main purpose of this study was to solve this problem by applying a new wetting method, which mixes ice powder with bentonite powder (the ice-bentonite mixing method). This new method was used to adjust the water distribution in Gaomiaozi County, China (GMZ) bentonite powder and was compared to the traditional spray method. The screening method was used to separate macro-agglomerates (≥ 0.25 mm) from the water and bentonite mixture. The properties, the content of the various size agglomerates in loose mixtures, and the heterogeneity defects observed in compacted bentonite were compared. An index (P) was defined to quantitatively evaluate the water distribution in a loose bentonite/water mixture. Macro-agglomerates in loose mixtures produced heterogeneities in water content, density, and shrinkage. By using the ice-bentonite mixing method, fewer macro-agglomerates were formed and a homogeneous distribution of water was produced in the compacted bentonite. A homogeneous water distribution had the tendency to decrease the number of shrinkage cracks after the drying process and to maintain high mechanical strength in the compacted bentonite. Although the production of ice powder was laborious, the ice-bentonite mixing method has workability advantages: (i) a high mixing efficiency, (ii) a low mass loss rate, and (iii) a small deviation between measured water content and target water content. The low thawing efficiency of ice-bentonite mixtures can be solved by using a microwave-assisted thawing method. This research can improve the sample preparation method used to produce compacted buffer/backfill materials for HLW disposal.

Keywords

AgglomeratesBentoniteCompacted Buffer/Backfill MaterialsHomogeneityIce-Bentonite Mixing MethodWater Content
Type
Article
Information
Clays and Clay Minerals , Volume 64 , Issue 6 , December 2016 , pp. 706 - 718
Copyright
Copyright © Clay Minerals Society 2016

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Footnotes

This paper is published as part of a special section on the subject of ‘Clay and fine particle-based materials for environmental technologies and clean up,’ arising out of presentations made during the 2015 Clay Minerals Society-Euroclay Conference held in Edinburgh, UK..

References

Atiemo-Obeng, V.A. Penney, W.R. and Armenante, P., 2004 Handbook of Industrial Mixing: Science and Practice Hoboken John Wiley & Sons 543.Google Scholar
Barden, L. and Sides, G.R., 1970 Engineering behavior and structure of compacted clay Journal of the Soil Mechanics & Foundations Division 96 1171–1200.CrossRefGoogle Scholar
Bastiaens, W. Bernier, F. and Li, X.L., 2007 SELFRAC: Experiments and conclusions on fracturing, self-healing and self-sealing processes in clays Physics and Chemistry of the Earth, Parts A/B/C 32 600–615.CrossRefGoogle Scholar
Becher, H.H., 1995 Soil structure: its development and function York CRC Press, New 53.Google Scholar
Bedeian, A.G. and Mossholder, K.W., 2000 On the use of the coefficient of variation as a measure of diversity Organizational Research Methods 3 285–297.CrossRefGoogle Scholar
Birkholzer, J. Houseworth, J. and Tsang, C.F., 2012 Geologic disposal of high-level radioactive waste: status, key issues, and trends Annual Review of Environment and Resources 37 79–106.CrossRefGoogle Scholar
Breusch, T.S. and Pagan, A.R., 1979 A simple test for heteroscedasticity and random coefficient variation Econometrica: Journal of the Econometric Society 47 1287–1294.CrossRefGoogle Scholar
Cai, Y. Shi, B. Liu, Z.B. Tang, C.S. and Wang, B.J., 2005 Experimental study on effect of aggregate size on strength of filled soils Chinese Journal of Geotechnical Engineering 27 1482–1486.Google Scholar
Candan, F. and Broquen, P., 2009 Aggregate stability and related properties in NW Patagonian Andisols Geoderma 154 42–47.CrossRefGoogle Scholar
Camprubí, M. Cònsola, M. Vallory, X., Mileto, C. Vegas, F. Garc¿a Soriano, L. and Cristini, V., 2014 Study of the behavior of agglomerates with lime: Mortars, concretes, soils Vernacular Architecture: Towards a Sustainable Future Boca Raton CRC Press.Google Scholar
Chapman, N.A. and McKinley, I.G. (1989) The geological disposal of nuclear waste. John Wiley and Sons Inc., New York, 12 pp.Google Scholar
Chegbeleh, L.P. Nishigaki, M. Akudago, J.A. Alim, M.A. and Komatsu, M., 2008 Concepts of repository and the functions of bentonite in repository environments: A stateof-the-art review Journal of the Faculty of Environmental Science and Technology, Okayama University 13 1–5.Google Scholar
Cheng, Y. Shi, M.L. and Zhou, Z.M., 2008 Aggregation effect of slaked lime on treated expansive soils Rock and Soil Mechanics 29 220–2214.Google Scholar
Cui, S.L. Zhang, H.Y. and Zhang, M., 2012 Swelling characteristics of compacted GMZ bentonite-sand mixtures as a buffer/backfill material in China Engineering Geology 141 65–73.CrossRefGoogle Scholar
Dixon, D. Sanden, T. Jonsson, E. and Hansen, J., 2011.Backfilling of deposition tunnels: Use of bentonite pellets SKB Report P-11-44Google Scholar
Dohrmann, R. Kaufhold, S. Lundqvist, B., Bergaya, F. and Lagaly, G., 2013 The role of clays for safe storage of nuclear waste Handbook of Clay Science: Techniques and Applications Amsterdam Elsevier 677–710.CrossRefGoogle Scholar
Harrington, J.F. and Horseman, S.T., 2003.Gas migration in KBS-3 buffer bentonite: Sensitivity of test parameters to experimental boundary conditions SKB Technical Report TR-03-02.Google Scholar
Hedin, A. and Andersson, J., 2014.safety case for a final repository license application. The Safety Case for Deep Geological Disposal of Radioactive Waste: 2013 State of the Art Radioactive Waste Management NEA/RWM/ R(2013)9 March 2014Google Scholar
Hillel, D., 1998 Environmental Soil Physics: Fundamentals, Applications, and Environmental Considerations San Diego Academic press 106.Google Scholar
Hoffmann, C. Alonso, E.E. and Romero, E., 2007 Hydromechanical behaviour of bentonite pellet mixtures Physics and Chemistry of the Earth, Parts A/B/C 32 832–849.CrossRefGoogle Scholar
Horn, R. Baumgartl, T. Kayser, R. and Baasch, S., 1995 Soil Structure: Its Development and Function Florida, USA CRC Press, Boca Raton 31.Google Scholar
Ichikawa, Y. Kawamura, K. Nakano, M. Kitayama, K. and Kawamura, H., 1999 Unified molecular dynamics and homogenization analysis for bentonite behavior: current results and future possibilities Engineering Geology 54 21–31.CrossRefGoogle Scholar
Inspectorate, S.N.P., 2003.Long-term Integrity of the KBS-3 Engineered Barrier System: Synthesis and Extended Abstracts SKB Report R-03-29Google Scholar
Johanesson, L.E., 1999.Compaction of full size blocks of bentonite for the KBS-3 concept-Initial tests for evaluating the technique SKB Report R-99-66Google Scholar
Johannesson, L.E. Sanden, T. and Dueck, A., 2008.Deep repository-Engineered barrier system. Wetting and homogenization processes in backfill materials. Laboratory tests for evaluating modeling parameters SKB Report R-08-136Google Scholar
Karnland, O. Sandén, T. Johannesson, L.E. Eriksen, T.E. Jansson, M. Wold, S. and Rosborg, B., 2000.Long term test of buffer material. Final report on the pilot parcels SKB TR-00-22Google Scholar
Kaufhold, S. Dohrmann, R. and Klinkenberg, M., 2010 Water-uptake capacity of bentonites Clays and Clay Minerals 58 37–43.CrossRefGoogle Scholar
Kaufhold, S. and Dohrmann, R., 2016 Distinguishing between more and less suitable bentonites for high-level radioactive waste Clay Minerals 51 289–302.CrossRefGoogle Scholar
Kobayashi, I. Toida, M. and Sasakura, T., 2008 Development of water content adjustment method using powdered ice and chilled bentonite: application to the construction of bentonite engineered barriers by shotclay method Science and Technology Series 334 77–84.Google Scholar
Koch, D., 2008 European bentonites as alternatives to MX-80 Science and Technology Series 334 23–30.Google Scholar
Laaksonen, R., 2010.MANU-Handling of Bentonite Prior Buffer Block Manufacturing Posiva Working Report WR-09-63Google Scholar
Lado, M. Ben-Hur, M. and Shainberg, I., 2004 Soil wetting and texture effects on aggregate stability, seal formation, and erosion Soil Science Society of America Journal 68 1992–1999.CrossRefGoogle Scholar
Liu, Y.M. and Chen, Z.R., 2001 Bentonite from GaoMiaozi, Inner Mongolia as an ideal buffer/backfilling material in handling highly radioactive wastes Acta Mineralogica Sinica 21 541–543.Google Scholar
Luo, S.H. Qian, Q.H. and Zhou, W.B., 2004 Deep geological disposal of high-level nuclear waste and its research outlines Chinese Journal of Rock Mechanics and Engineering 23 831–838.Google Scholar
Ma, R. Cai, C. Li, Z. Wang, J. Feng, J. Wu, X. and Zhu, H., 2014 Effect of antecedent soil moisture on aggregate stability and splash erosion of krasnozem Transactions of the Chinese Society of Agricultural Engineering 30 95–103.Google Scholar
Marsily, G.D. Ledoux, E. Barbreau, A. and Margat, J., 1977 Nuclear waste disposal: can the geologist guarantee isolation Science 197 519–527.CrossRefGoogle ScholarPubMed
Muurinen, A. Karnland, O. and Lehikoinen, J., 2007 Effect of homogenization on the microstructure and exclusion of chloride in compacted bentonite Physics and Chemistry of the Earth, Parts A/B/C 32 485–490.CrossRefGoogle Scholar
Murungu, F.S. Nyamugafata, P. Chiduza, C. Clark, L.J. and Whalley, W.R., 2003 Effects of seed priming, aggregate size and soil matric potential on emergence of cotton (Gossypium hirsutum L.) and maize (Zea mays L.) Soil and Tillage Research 74 161–168.CrossRefGoogle Scholar
Neretnieks, I., 1985 Diffusivities of some constituents in compacted wet bentonite clay and the impact on radionuclide migration in the buffer Nuclear Technology 71 458–470.CrossRefGoogle Scholar
Nienow, A.W. Edwards, M.F. and Harnby, N., 1997 Mixing in the Process Industries Oxford Butterworth-Heinemann 414.Google Scholar
Oscarson, D.W. Hume, H.B. and King, F., 1994 Sorption of cesium on compacted bentonite Clays and Clay minerals 42 731–736.CrossRefGoogle Scholar
Pusch, R., 1979 Highly compacted sodium bentonite for isolating rock-deposited radioactive waste products Nuclear Technology 45 153–157.CrossRefGoogle Scholar
Pusch, R., 1983.Use of clays as buffers in radioactive repositories SKB Technical Report TR-83-46Google Scholar
Pusch, R. Ranhagen, L. Nilsson, K. and Geological, S., 1985.Gas migration through Mx-80 bentonite. Final report NAGRA Technical Report TR-85-36Google Scholar
Qin, B. Chen, Z.H. Liu, Y.M. and Wang, J., 2008 Swelling-shrinkage behaviour of Gaomiaozi bentonite Chinese Journal of Geotechnical Engineering 30 1005–1010.Google Scholar
Rasilainen, K., 2004.Localisation of the SR 97 Process Report for Posiva’s spent fuel repository at Olkiluoto Posiva Report, R-04-05Google Scholar
Reid, C. Lunn, R. El Mountassir, G. and Tarantino, A., 2015 A mechanism for bentonite buffer erosion in a fracture with a naturally varying aperture Mineralogical Magazine 79 1485–1494.CrossRefGoogle Scholar
Ritola, J. and Pyy, E., 2012.Isostatic compression of buffer blocks: middle scale Posiva Working Report WR-11-62Google Scholar
Sellin, P. and Leupin, O., 2014 The use of clay as an engineered barrier in radioactive waste management — a review Clays and Clay Minerals 61 477–498.CrossRefGoogle Scholar
Shi, B. Murakami, Y. and Wu, Z., 1998 Orientation of aggregates of fine-grained soil: quantification and application Engineering Geology 50 59–70.CrossRefGoogle Scholar
Stavi, I. Ungar, E.D. Lavee, H. and Sarah, P., 2010 Variability of soil aggregation in a hilly semi-arid rangeland Journal of Arid Environments 74 946–953.CrossRefGoogle Scholar
KBS-3 (1983) Final storage of spent nuclear fuel: KBS-3. Swedish Nuclear Fuel and Waste Management Co., Stockholm.Google Scholar
van Geet, M. and Dohrmann, R., 2016 Overview of the clay mineralogy studies presented at the ‘Clays in natural and engineered barriers for radioactive waste confinement’ meeting, Brussels Clay Minerals 51 125–128.CrossRefGoogle Scholar
Venkatesh, M.S. and Raghavan, G.S.V., 2004 An overview of microwave processing and dielectric properties of agri-food materials Biosystems Engineering 88 1–18.CrossRefGoogle Scholar
Vieno, T. and Ikonen, A.T. (2005) Plan for safety case of spent fuel repository at Olkiluoto. Posiva Oy, Report, 1.Google Scholar
Wang, J., 2010 High-level radioactive waste disposal in China: update 2010 Journal of Rock Mechanics and Geotechnical Engineering 2 1–11.Google Scholar
Wen, Z.J., 2005 Selection and properties of China’s buffer materials for high level radioactive waste repository Acta Petrologica et Mineralogica 24 583–586.Google Scholar
Wuddivira, M.N. Ekwue, E.I. and Stone, R.J., 2010 Modelling slaking sensitivity to assess the degradation potential of humid tropic soils under intense rainfall Land Degradation & Development 21 48–57.CrossRefGoogle Scholar
Ye, W.M. Chen, Y.G. Chen, B. Wang, Q. and Wang, J., 2010 Advances on the knowledge of the buffer/backfill properties of heavily-compacted GMZ bentonite Engineering Geology 116 12–20.CrossRefGoogle Scholar
Yoder, R.E., 1936 A direct method of aggregate analysis of soils and a study of the physical nature of erosion losses Agronomy Journal 28 337–351.CrossRefGoogle Scholar
Zhang, H.Y. Liang, J. Liu, J.S. and Cui, S.L., 2009 Compaction properties of bentonite-sand mixture as buffer material for HLW disposal Chinese Journal of Rock Mechanics and Engineering 28 2585–2592.Google Scholar
Zhang, M. Zhang, H.Y. Jia, L.Y. and Cui, S.L., 2012 Method for sample preparation of buffer/backfilling materials in laboratory Journal of Building Materials 15 638–643.Google Scholar
Zhou, L. Zhang, H.Y. Yan, M. Chen, H. and Zhang, M., 2013 Laboratory determination of migration of Eu (III) in compacted bentonite-sand mixtures as buffer/backfill material for high-level waste disposal Applied Radiation and Isotopes 82 139–144.CrossRefGoogle ScholarPubMed