Retardation of heavy metals in clay-solidified grouting curtain of municipal landfills

The performance of clay-solidified grouting curtain to prevent seepage of leachate containing heavy metals from the landfill into the environment was investigated. Numerical simulations were carried out using reactive solute transport model to study the retardation of heavy metals (Cd2+, Pb2+, Hg2+) in the clay-solidified grouting curtain. The laboratory simulation test results show that precipitate produced in heavy metal cation migration process in curtain block up water flowing pas sage which makes the hydraulic conductivity of the solution-permeated curtain decreased with leakage time and that migration rapidity for different heavy metal cations vary with ionic concentration, exchange capacity, and ion radius etc. In addition, penetrations for different mixture ratio and antisepsis capabilities of the curtain were researched in tests.