PDF(553 KB)
PDF(553 KB)

PDF(553 KB)
干湿循环与垃圾渗滤液耦合作用下GCL防渗性能
Hydraulic performance of GCL under wet-dry cycling concurrent with municipal solid waste leachate permeation
开展膨胀指数和渗透系数测定试验,研究干湿循环与垃圾渗滤液渗透耦合作用下膨润土的膨胀性能和土工合成黏土衬垫(GCL)防渗性能变化规律.结果表明,干湿循环与垃圾渗滤液渗透耦合作用对膨润土的膨胀性能和GCL的防渗性能具有显著负面影响:在7次干湿循环后,垃圾渗滤液饱和的膨润土的膨胀指数从20mL/2g降低至7.5mL/2g,GCL的渗透系数从1.65×10-11m/s增加到1.89×10-7m/s.膨胀指数下降和渗透系数升高的根本原因是膨润土渗透膨胀性能的丧失.单纯的垃圾渗滤液渗透不会改变GCL的渗透系数.将有效应力从20kPa升高至150kPa,可以促使GCL的渗透系数降低4个数量级,满足填埋场防渗要求(< 5.0x10-11m/s).
Laboratory free swell and hydraulic conductivity tests were conducted to assess the effect of wet-dry cycling concurrent with landfill leachate permeation on the swell index of bentonite and hydraulic performance of a geosynthetic clay liner (GCL). Wet-dry cycling concurrent with leachate permeation had a significantly detrimental effect on the swell index of bentonite and hydraulic performance of GCL. The swell index of bentonite decreased from 20mL/2g to 7.5mL/2g and the hydraulic conductivity of GCL increased from 1.65×10-11m/s to 1.89×10-7m/s. The decrease in the swell index of bentonite and the increase in hydraulic conductivity of GCL should be attributed to the loss of osmotic swell of bentonite. The GCL continuously permeated with municipal solid waste leachate maintained a low k during the entire study duration. Increasing the effective stress from 20 to 150kPa caused the hydraulic conductivity of GCL to decrease by almost 4orders of magnitude and lower than the maximum value (5.0×10-11m/s) allowed for GCL used in municipal solid waste landfill.
干湿循环 / 垃圾渗滤液 / 耦合 / 渗透系数 / 土工合成黏土衬垫
concurrent / geosynthetic clay liner / hydraulic conductivity / municipal solid waste leachate / wet-dry cycling
[1] 李志斌,徐超.竖向应力作用下GCL的膨胀特性和渗透性能[J]. 岩土工程学报, 2007,29(12):1876-1880. Li Z B, Xu C. Swelling characteristics and hydraulic properties of GCLs under vertical stress[J]. Chinese Journal of Geotechnical Engineering, 2007,29(12):1876-1880.
[2] Bouazza A. Geosynthetic clay liner[J]. Geotextiles and Geomembranes, 2002,20(1):3-17.
[3] 郭争争,管俊芳,陈菲,等.膨润土防水毯应用进展[J]. 硅酸盐通报, 2018,37(11):3449-3453. Guo Z Z, Guan J F, Chen F, et al. Progress in Application of Geosynthetic Clay Liner[J]. Bulletin of the Chinese Ceramic Society, 2018,37(11):3449-3453.
[4] CJJ 113-2007生活垃圾卫生填埋场防渗系统工程技术规范[S]. CJJ 113-2007 Technical code for liner system of municipal solid waste landfill[S].
[5] 董兴玲,董书宁,王宝,等.黄土淋滤液作用下土工合成黏土衬垫的渗透特性研究[J]. 煤炭学报, 2018,43(1):228-235. Dong X L, Dong S N, Wang B, et al. Hydraulic conductivity of geosynthetic clay liners to loess leachate[J]. Journal of China Coal Society, 2018,43(1):228-235.
[6] Rubl J L, Daniel D E. Geosynthetic clay liners permeated with chemical solutions and leachates[J]. Journal of Geotechnical and Geoenvironmental Engineering, 1997,123(4):369-381.
[7] Rauen T, Benson C. Hydraulic conductivity of a geosynthetic clay liner permeated with leachate from a landfill with leachate recirculation[Z]. Cancun, Mexico:2008:76-83.
[8] Bradshaw S, Benson C. Effect of municipal solid waste leachate on hydraulic conductivity and exchange complex of geosynthetic clay liners[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2014,140(4):1-17.
[9] Bradshaw S L, Benson C H, Rauen T L. Hydraulic conductivity of geosynthetic clay liners to recirculated municipal solid waste leachates[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2016,142(2):4015074.
[10] Rowe R K. Geosynthetic clay liners:Perceptions and misconceptions[J]. Geotextiles and Geomembranes, https://doi.org/10.1016/j.geotexmem.2019.11.012.
[11] ASTM D 6766 Standard test method for evaluation of hydraulic properties of geosynthetic clay liners permeated with potentially incompatible aqueous solutions[S].
[12] ASTM D 5890-06 Standard Test method for swell index of clay mineral component of geosynthetic clay liner[S].
[13] Lake C B, Rowe R K. Diffusion of sodium and chloride through geosynthetic clay liners[J]. Geotextiles and Geomembranes, 2000, 18(2-4):103-131.
[14] Sarabian T, Rayhani M T. Hydration of geosynthetic clay liners from clay subsoil under simulated field conditions[J]. Waste Management, 2013,33(1):67-73.
[15] 张振营.城市生活垃圾的压缩性及填埋场的沉降研究[D]. 杭州:浙江大学, 2005. Zhang Z Y. Study on compressibility and settlement of landfill for municipal solid waste[D]. Hangzhou:Zhejiang University, 2005.
[16] 高武,詹良通,兰吉武,等.高渗滤液水位填埋场的填埋气高效收集探究[J]. 中国环境科学, 2017,37(4):1434-1441. Gao W, Zhan L T, Lan J W, et al. Exploration on efficient collection of landfill gas in a landfill with a high leachate level[J]. China Environmental Science, 2017,37(4):1434-1441.
[17] Lee J, Shackelford C D, Benson C H, et al. Correlating index properties and hydraulic conductivity of geosynthetic clay liners[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2005,131(11):1319-1329.
[18] Shan H, Lai Y. Effect of hydrating liquid on the hydraulic properties of geosynthetic clay liners[J]. Geotextiles and Geomembranes, 2002, 20(1):19-38.
[19] JC/T 2054-2011天然钠基膨润土防渗衬垫[S]. JC/T 2054-2011 Natural sodium bentonite impervious liner[S].
[20] Lin L, Benson C. Effect of wet-dry cycling on swelling and hydraulic conductivity of GCLs[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2000,126(1):40-49.
[21] Benson C, Meer S. Relative Abundance of monovalent and divalent cations and the impact of desiccation on geosynthetic clay liners[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2009, 135(3):349-358.
[22] De Camillis M, Di Emidio G, Bezuijen A, et al. Hydraulic conductivity and swelling ability of a polymer modified bentonite subjected to wet-dry cycles in seawater[J]. Geotextiles and Geomembranes, 2016,44(5):739-747.
[23] De Camillis M, Di Emidio G, Bezuijen A, et al. Effect of wet-dry cycles on polymer treated bentonite in seawater:swelling ability, hydraulic conductivity and crack analysis[J]. Applied Clay Science, 2017,142:52-59.
[24] Rowe R K, Garcia J D D, Brachman R W I, et al. Chemical interaction and hydraulic performance of geosynthetic clay liners isothermally hydrated from silty sand subgrade[J]. Geotextiles and Geomembranes, 2019,47(6):740-754.
[25] Kolstad D, Benson C, Edil T. Hydraulic conductivity and swell of nonprehydrated geosynthetic clay liners permeated with multispecies inorganic solutions[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2004,130(12):1236-1249.
[26] Meer S R, Benson C H. Hydraulic conductivity of geosynthetic clay liners exhumed from landfill final covers[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2007,133(5):550-563.
[27] Egloffstein T A. Natural bentonites-influence of the ion exchange and partial desiccation on permeability and self-healing capacity of bentonites used in GCLs[J]. Geotextiles and Geomembranes, 2001, 19(7):427-444.
国家自然科学基金资助项目(41602291);天地科技股份有限公司科技创新创业资金专项项目(2018-TD-MS073)
/
| 〈 |
|
〉 |