Abstract
Experiments were conducted to evaluate the compatibility of bentonite-polymer (B-P) GCLs to Coal Combustion Product (CCP) leachates. The B-P GCLs were manufactured by dry-mixing polymer and sodium bentonite (NaB). Six synthetic leachates were selected based on database of coal ash leachates. Hydration characteristics (i.e., free swell index) and hydraulic conductivity of B-P GCLs were investigated using deionized water and synthetic leachates. The hydraulic conductivity of B-P GCL with low polymer loading (1.2%) is strongly affected by the ionic strength of leachates and controlled by swelling of bentonite. However, the hydraulic conductivity of B-P GCL with high polymer loading (≥5.1%) is controlled primarily by hydrogel blockage in the pore space. Polymer hydrogel forms reticular structure and bonds free water when hydrated with DI water. However, under 20 mM CaCl2, the reticular structure of polymer hydrogel is inhibited by self-entanglement due to divalent cations and high ionic strength.
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References
EPRI (2009) Coal ash: characteristics, management, and environmental issues. Electric Power Research Institute, Palo Alto, CA. 1019022
USEPA 40 CFR Parts 257 and 261 (2015) Hazardous and solid waste management system; disposal of coal combustion residuals from electric utilities; final rule. USEPA
Shackelford C, Benson C, Katsumi T, Edil T, Lin L (2000) Evaluating the hydraulic conductivity of GCLs permeated with non-standard liquids. Geotext Geomembr 18(2–4):133–162
Jo H, Katsumi T, Benson C, Edil T (2001) Hydraulic conductivity and swelling of non-prehydrated GCLs permeated with single species salt solutions. J Geotech Geoenviron Eng 127(7):557–567
Chen J, Benson CH, Edil TB (2017) Hydraulic conductivity of geosynthetic clay liners with sodium bentonite to coal combustion product leachates. J Geotech Geoenviron Eng 144(3):04018008
Xu C, Li Z, Gao Y (2009) Influence of solution characteristics on swelling and hydration performance of geosynthetic clay liners. J Tonji Univ (Nat Sci) 37(1):36–40
Kolstad D, Benson C, Edil T (2004) Hydraulic conductivity and swell of non-prehydrated GCLs permeated with multi-species inorganic solutions. J Geotech Geoenviron Eng 130(12):1236–1249
Ruhl J, Daniel D (1997) Geosynthetic clay liners permeated with chemical solutions and leachates. J Geotech Geoenviron Eng 123(4):369–381
Bradshaw S, Benson C (2013) Effect of municipal solid waste leachate on hydraulic conductivity and exchange complex of geosynthetic clay liners. J Geotech Geoenviron Eng 140(4):04013038
Katsumi T, Ishimori H, Ogawa A et al (2007) Hydraulic conductivity of nonprehydrated geosynthetic clay liners permeated with inorganic solutions and waste leachates. Soils Found JGS 1:79–96
Di Emedio G, Van Impe W, Flores V (2011) Advances in geosynthetic clay liners: polymer enhanced clays. In: GeoFrontiers 2011. Advances in geotechnical engineering, American society of civil engineers, Reston, pp 1931–1940
Mazzieri F, Emidio G, Van Impe P (2010) Diffusion of calcium chloride in a modified bentonite: Impact on osmotic efficiency and hydraulic conductivity. Clays Clay Miner 58(3):351–363
Scalia J, Benson C, Bohnhoff G, Edil T, Shackelford C (2014) Long-term hydraulic conductivity of a bentonite-polymer composite permeated with aggressive inorganic solutions. J Geotechnol Geoenviron Eng 140:040130251
Katsumi T, Ishimori H, Onikata M, Fukagawa R (2008) Long-term barrier performance of modified bentonite materials against sodium and calcium permeant solutions. Geotext Geomembr 26(1):14–30
Shackelford CD, Sevick GW, Eykholt GR (2010) Hydraulic conductivity of geo-synthetic clay liners to tailings impoundment solutions. Geotext Geomembr 28(2):149–162
Scalia J (2012) Bentonite-polymer composites for containment applications. Ph.D. Dissertation, University of Wisconsin, Madison, WI
EPRI (2006) Characterization of field leachates at coal combustion product management sites. Electric Power Research Institute, Palo Alto, p 1012578
Tian K, Benson C, Likos W (2016) Hydraulic conductivity of geosynthetic clay liners to low-level radioactive waste leachate. J Geotech Geoenviron Eng 04016037:1–12
Bulo RE, Donadio D, Laio A, Molnar F, Rieger J et al (2007) Site binding of Ca2+ ions to polyacrylates in water: a molecular dynamics study of coiling and aggregation. Macromolecules 40:3437–3442
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The Electric Power Research Institute (EPRI) provided financial support for this study. National Science Foundation of China (41701347) supported the partial travel expenses of Dr. Chen.
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Chen, JN., Tian, K., Benson, C.H. (2019). Hydraulic Conductivity of Bentonite-Polymer Geosynthetic Clay Liners to Coal Combustion Product Leachates. In: Zhan, L., Chen, Y., Bouazza, A. (eds) Proceedings of the 8th International Congress on Environmental Geotechnics Volume 2. ICEG 2018. Environmental Science and Engineering(). Springer, Singapore. https://doi.org/10.1007/978-981-13-2224-2_82
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