污水厂污泥制备垃圾填埋场防渗衬层材料研究

以城市污水厂的污泥复合高岭土用作垃圾填埋场防渗衬层材料，研究了千污泥的掺入量及其颗粒大小、复合土密度、渗滤液性质对污泥复合土渗透性能的影响。结果表明，复合土中污泥的最佳质量分数为40％；提高复合土的干密度可显著降低其渗透系数，当干密度为1.08g／cm^3时复合土的渗透系数达10^-7cm／s数量级，符合垃圾填埋场防渗衬层的要求；渗滤液性质对渗透性能的影响较大，当其电解质浓度较大时复合土的渗透性能随之提高。此外，考察了污泥复合土对重金属的吸附效果，结果表明该复合土可有效吸附垃圾渗滤液中的Cu^2＋、Zn^2＋等重金属。

Study on Use of Urban Sewage Sludge as Impervious Liner Material in Landfill Site

The compound clay of urban sewage sludge and kaolin was used as the impervious liner material in landfill site.The influence of the sludge dosage and granule size,the compound clay density and the leachate characteristic on the permeating performance of compound clay was studied.The results show that the optimal mixing ratio of sludge is 40%.The permeating coefficient of compound clay can be reduced with its dry density increasing.The permeating coefficient of compound clay will reach 10~(-7) cm/s grade which meets the criterion of the impervious liner in landfill site when the dry density is 1.08 g/cm~3.The leachate characteristic can greatly affect the permeating performance of compound clay.The permeability of compound clay will be increased when the electrolytic concentration in the leachate is increased.Moreover,the adsorption effect of the heavy metals by the compound clay was investigated.The result shows the compound clay has a high adsorption of Cu~(2+) and Zn~(2+) in landfill leachate.