用改性膨润土作垃圾填埋场底部衬里的试验

Test studies on using modified bentonite as the base bottom liner in the garbage landfill

结合JeanFrank提出的双层矿物基底衬里(DMBL)的新概念设计了新型垃圾填埋场的底部防护系统,通过土柱对比实验,对DMBL中的高度反应层和“惰性”层位置不同时,衬里对渗滤液的渗透和衰减能力进行了研究.结果表明,无论高度反应层在“惰性”层的上方还是下方,DMBL的渗透系数可达到1×10-7cm/s以下,但有机膨润土层放置在“惰性”层下方时,不但防渗性能较好,而且对渗滤液中有机物、铁离子的去除率分别达到58%、98%,对NH4+、锌离子等也表现出较好的去除效果.

Combining the new concept of double mineral base liner put forward by Jean Frank, a new type protection system of the garbage landfill was designed; the attenuation and permeability of the liner at different positions of the highly active layer and the inactive layer of DMBL were studied through soil column comparing test. No matter above or below the active on the inactive layer, the permeability coefficient of DMBL could reach lower than 1×10^-7cm/s; but when the position of the organic bentonite was below the inactive layer not only the permeability protection character was better; and the removal rates of organism and Fe ion also reached 58% and 98% respectively, with better removal effect on NH4^＋ and Zn^2＋ion.