Experimental Research on Anti-seepage Slurry for Waste Landfill

In order to develop one kind of slurry with low permeability coefficient and certain adsorption and block to pollutants in leachate, it is used in anti-seepage engineering of leachate for landfill site. Through the orthogonal experiment, the selected optimal formula of the slurry with a bentonite base is: bentonite 22%similar to 30%; cement 16%similar to 28%; fly ash 18%similar to 26%; Na2CO3 0.8%similar to 1.5%; NUF-5 0.25%similar to 0.72%; filaments 0.01%similar to 0.05% and etcaeteras is water. Concretion stone ratio of this slurry is greater than 99.5%; concretion body 28 day permeability coefficient is less than 0.9 x 10(-7) cm/s, unconfined compressive strength is less than 2.5MPa; elastic modulus is 60 similar to 800MPa. The slurry concretion body's hindered COD, BOD, NH4-N and phosphorus adsorption rates reach upper 85%, block rate reaches upper 99% to Hg, Pb and other heavy metal ions. The slurry concretion body's permeability coefficient is low, and its adsorbed or blocked function to landfill site leachate is very well. Meanwhile, it has considered reducing the compressive strength and brittleness of the concretion body, enabling it to have certain plasticity and toughness adapted for the distortion of the base for domestic waste landfill site.