粉煤灰基多孔陶粒制备及其生物载体除污效果

Preparation of porous ceramsite by fly ash and its utilization in biological aerated filter reactors

以电厂粉煤灰为原料,制备出表观密度为1.20g/cm3、显气孔率为50.13%、比表面积为4.21m2/g和平均孔径为2.31μm的多孔陶粒,并将其作为曝气生物滤池中污水处理的生物载体。通过SEM、XRD分析和重金属浸出分析,发现陶粒为表面粗糙的多孔材料,焙烧后新生矿物为硅酸盐类钙长石,多孔陶粒浸出液中重金属浓度达到国家地表水质量要求。处理生活污水显示,曝气生物滤池去除CODcr、NH4+-N和TN的容积负荷分别为5.11、0.97、0.33kg/(m3·d),其去除率分别达到84.56%、96.01%和31.29%;滤料表面和内部生物量分别为290.29、16.47nmol P/g滤料,其分别占总量的94.63%和5.37%。

The porous ceramsite used in a biological acerated filter（BAF） reactor for sewage treatment was prepared by the fly ash,whose density,porosity,specific surface area and average pore size under optimum preparation were 1.20 g/cm^3,50.13%,4.21 m^2/g and 2.31 μm,respectively.SEM and XRD analyses find that it is a porous material with roughening surface,and its sintering yields silicate anorthite.Heavy metal leaching experiment shows that the concentration of heavy metals from the ceramsite meets the China Environmental Quality Standards for Surface Water.The simulated sewage treatment test shows that,when CODcr,NH＋4-N and TN in the BAF are 5.11,0.97 and 0.33 kg·（m^3·d）-1,the removal of CODcr,NH＋4-N and TN reaches 84.56%,96.01% and 31.29%,respectively.The biomass examination shows that the biomass attached to the surface and internal hole of the ceramsite in the bio-filter are 290.29 and 16.47 nmol P/g,accounting for 94.63% and 5.37% of the total,respectively.