垃圾填埋场中水泥土屏障对Cu2+的阻滞性能

Blocking Performance of Cement-Soil Barrier upon Cu2+ in Municipal Solid Waste Landfills

摘要:

通过室内模型试验，研究了不同水泥掺量的水泥土防渗屏障和上海老港填埋场的膨润土砂水泥(塑性混凝土)防渗屏障对Cu2+的阻滞效果，并应用数值模拟的方法对Cu2+在防渗屏障中的有效扩散系数进行求解.研究结果表明，随着水泥掺量和屏障厚度的增加，水泥土屏障对金属离子的阻滞效果会逐步提升；Cu2+在水泥土中的有效扩散系数(1×10-7~2.5×10-7 cm2?s-1)是在土中的有效扩散系数(9.53×10-6~1.14×10-5 cm2?s-1)的1/35~1/100；上海老港填埋场中的塑性混凝土防渗屏障对Cu2+有较好的阻滞效果.

Abstract:

In this paper, the effects of cement-soil barrier with different cement content and bentonite-sand-cement (plastic concrete) barrier used in Shanghai Laogang landfill are studied through the laboratory model test. The effective diffusion coefficients of copper ions in the impervious barrier are solved by using numerical simulation method. The experimental results showed that with the increase of cement content and barrier thickness, the blocking effect of the cementsoil barrier on metal ions will be increased gradually. The effective diffusion coefficient (1×10-7~4×10-7 cm2?s-1) of copper ions in cement soil is 1/25~1/100 of the effective diffusion coefficient in soil (9.53×10-6~1.14×10-5 cm2?s-1).The plastic concrete impervious barrier used in Shanghai Laogang landfill has good blocking effect on copper ions.