城市垃圾填埋场防渗浆材的实验研究

针对垃圾填埋场防渗的特殊要求,通过大量正交实验研究,研制了一种低渗透系数并对污染物有良好阻滞作用的浆材,即膨润土-水泥-粉煤灰(BCF)浆材,包括S型、N型和Z型3种类型。该浆材可泵期可调,结实率>99.6%,结石体28d渗透系数<0.65×10-7cm/s,N型的无侧限抗压强度<1.2MPa,弹性模量在200MPa左右。浆材结石体对COD、氨氮和磷的阻滞率均达到了82%以上,对酞酸酯和常见重金属离子的阻滞率均在99.6%以上。对浆材结石体的防渗性与对污染物阻滞性能的机理进行了研究,并提出渗滤沉积作用和吸附滞留作用阻滞机理。

TEST RESEARCH ON ANTISEEPAGE SLURRY FOR URBAN LANDFILL SITES

According to special seepage control requirements of a landfill site,through a large amount of orthogonal experiments,a kind of low permeability coefficient slurry,namely bentonite-cement-fly ash(BCF)slurry was developed,which showed good inhibition to pollutant. It included S,N and Z three types. The pumpability time of this slurry was adjustable and rate of bonding stone was greater than 99.6%. The permeability coefficient of the slurry concretion was below 0.65× 10-7 cm/s after 28 d,the unconfined compressive strength of the N type slurry concretion was less than 1.2 MPa and its elastic modulus was around 200 MPa. The blocking rates of slurry concretion to COD,NH3-N and phosphate were over 82% and the blocking rates of slurry concretion to Phthalate esters and common heavy metal ions were above 99.6%. The antiseepage and the mechanism of inhibition performance to the pollutant of slurry concretion were studied and the blocking mechanism of infiltration deposition,adsorption residence performance was proposed.