Study on isolation effect of cement-soil Barrier upon heavy metal in MSW landfills

Abstract:

Land filling is one of the most economical and efficient ways to treat Municipal Solid Waste (MSW). When cement-soil barrier is used in landfills as vertical barrier curtains, diffusion of contaminant is not taken into consolidation in design. In this paper, influence of barrier’s thickness and cement content on isolation effect of heavy metal is analyzed though a large model test. The results show that isolation effect will be enhanced greatly by increasing the cement content or thickness of barrier. Moreover, isolation effect that is enhanced by increasing the cement content of barrier is more than by increasing the thickness of barrier. The results also prove that the diffusion coefficient of Zn2+ in soil is far great than that in cement-soil.

Key words:landfill;cement-soil barrier;heavy metal ions;diffusion;cement content