【摘要】 根据GB/T50123-1999《土工试验方法标准》分别测定了膨润土、沸石和赤泥的风干含水率、干密度和渗透系数等参数。用膨润土、沸石和赤泥作防渗材料设计5种不同结构的防渗衬里,进行土柱试验。柱1、2和3依次为膨润土、沸石和赤泥单层矿物衬里,厚度均为4 cm;柱4为赤泥+膨润土+沸石,柱5为赤泥+沸石+膨润土的多层矿物衬里。分别测定各衬里的渗透系数和出水COD、氨氮、电导率和pH值的变化。结果表明:3种材料单独用作衬里时各项指标不能满足垃圾填埋场对衬里的要求(<10-7cm/s),而多层矿物衬里渗透系数可达10-8cm/s量级,对COD、电导率、氨氮的衰减率能够达到或优于3种材料单独用作防渗衬里时的最好水平,且出水pH值不呈强碱性。更多还原

【Abstract】 Moisture content,dry density and hydraulic conductivity of bentonite,zeolite and red mud were measured.Column tests were carried out with practical leachate for five columns composed of bentonite,zeolite and red mud in different structures.Column 1,2 and 3 are bentonite,zeolite and red mud monolayer liners,and column 4 and 5 are multilayer liners in the structure of red mud+bentonite+zeolite and red mud+zeolite +bentonite from top to bottom respectively.The thicknesses of all liners are 4 cm.The variations of the hydraulic conductivity,ammonium-nitrogen content,COD content,pH value and electrical conductivity of the leachates leaching through the five columns with time were measured.Results indicate that the performances of the multilayer liners including permeability,attenuation of ammonium-nitrogen,COD and electrical conductivity,buffering of pH and the stability of the liner’ s structure are superior to that of monolayer liners.更多还原