Hydraulic conductivity and swell index tests were conducted on a commercially available geosynthetic clay liner (GCL) containing a dry-blended bentonite-polymer (B-P) mixture using solutions with a single monovalent cation (Na~+) and varying anion ratio, R, defined as the molar concentration ratio of Cl~- to SO_4~(2-). Na~+ solutions with pure Cl~+ or SO_4~(2-) and with anion ratios of 5 and 20 were used as permeant liquids. Swell index of the B-P in 300 mM Na~+ solutions was independent of anion ratio (SI ~ 22.5 mL/2 g for all solutions). However, hydraulic conductivity of the B-P GCL permeated with NaCl was approximately three orders of magnitude greater than the hydraulic conductivity to Na_2SO_4. Comparative tests were conducted on a conventional GCL with sodium-bentonite (Na-B) with 100 and 300 mM Na~+ solutions with pure SO_4~(2-) and pure Cl~- as anions. Hydraulic conductivity of the Na-B GCL was unaffected by anion species (1.5 x 10~(-11) m/s for 100 mM NaCl, 2.1 × 10~(-11) m/s for 50 mM Na_2SO_4). Sensitivity of the B-P GCL to anion species is attributed to collapse of the polymer as the Cl" concentration increases, which opens intergranular pores and results in higher hydraulic conductivity.
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机译：在市售的土工合成粘土衬里（GCL）上进行了水力传导率和膨胀指数测试，该衬里包含干混膨润土-聚合物（BP）混合物，使用具有单个一价阳离子（Na〜+）和变化的阴离子比R的溶液进行了定义Cl〜-与SO_4〜（2-）的摩尔浓度比具有纯Cl〜+或SO_4〜（2-）且阴离子比为5和20的Na〜+溶液用作渗透液。 B-P在300 mM Na +溶液中的溶胀指数与阴离子比无关（所有溶液的SI〜22.5 mL / 2 g）。但是，渗透有NaCl的B-P GCL的水力传导率比对Na_2SO_4的水力传导率大约大三个数量级。在传统的GCL上进行了对比试验，该钠凝胶是用钠膨润土（Na-B）和100和300 mM Na〜+溶液，以纯SO_4〜（2-）和纯Cl〜-作为阴离子。 Na-B GCL的水力传导率不受阴离子种类的影响（对于100 mM NaCl为1.5 x 10〜（-11）m / s，对于50 mM Na_2SO_4为2.1×10〜（-11）m / s）。 B-P GCL对阴离子物质的敏感性归因于当Cl“浓度增加时聚合物的崩解，从而打开了晶间孔并导致更高的水力传导性。
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