Research of antiseepage slurry used in waste landfill sites and it´s properties

According to specific seepage control requirements for waste landfill site, not only slurry must have low permeability coefficient, but also effective adsorption and retardation to the pollutant. Based on these, slurry with low permeability coefficient and good retardation to the pollutant, namely bentonite - cement - fly ash (BCF) slurry, was developed through a large amount of orthogonal experiments. It includes S, N and Z three types. The pumpability time of this slurry was adjustable and rate of bond stone was greater than 99.6%. The permeability coefficient of the slurry concretion was below 0.65×10^-7cm/s after 28 days, the unconfined compression strength of the N type slurry concretion was less than 1.2MPa and the elastic modulus of it was around 200MPa. The blocking rate of slurry concretion to CODcr, NH₃-N and phosphate reached over 82%, and the blocking rate of slurry concretion to Phthalate esters and common heavy metal ions was above 99.6%. The antiseepage of slurry concretion and the mechanism of retardation performance to the pollutant were studied. The infiltration deposition and adsorption residence performance were discussed.