制革污泥固化稳定化处理

为有效控制制革污泥中的重金属铬污染并安全填埋,采用石灰、粉煤灰和煤渣作为固化剂对制革污泥进行固化/稳定化处理,考察固化剂对制革污泥中重金属毒性的影响,并探讨了固化/稳定化的最佳工艺条件.结果表明,当石灰、粉煤灰和煤渣的掺量分别为0.12 kg.kg-1、0.02 kg.kg-1和0.08 kg.kg-1,养护天数为6 d时,制革污泥固化块抗压强度达到884 kPa,含水率由固化前的79.60%降低至30.20%,满足《危险废物填埋污染控制标准》（GB 18598—2001）的要求.固化块浸出液中Cu、Pb、Zn、Ni浓度同固化前相比,分别降低了92.1%、96.7%、92.8%、88.9%,Cr、Cd、Mn均未检出.固化块浸出液的铬浓度随着石灰添加量的增加而降低,随粉煤灰添加量的增加则为先降低、然后再升高,当石灰与粉煤灰添加量比为6∶1时,协同固化效果显著.

Solidification/stabilization treatment of tannery sludge

In order to control the pollution of heavy metal chromium in tannery sludge effectively,sludge from tannery was solidified and stabilized by using lime,PFA and cinder as the solidifying agents.The effect of solidifying agents on Cr concentration in tannery sludge and the optimum conditions of sludge solidification/stabilization were analyzed.The results showed that,when the dosage of lime,PFA and cinder was 0.12 kg · kg-1,0.02 kg · kg-1 and 0.08 kg · kg-1 respectively,and curing time was 6 days,the compression strength of the solidified sludge block reached 884 kPa,and the moisture content of the solidified block reduced from 79.60% to 30.20%.The values met the "Standard for Pollution Control on the Security Landfill Site for Hazardous Wastes"(GB 18598—2001).Compared with the untreated tannery sludge,the concentrations of Cu,Pb,Zn,Ni in the leaching solution from the solidified block was reduced by 92.1%、96.7%、92.8%、88.9% respectively,and Cr,Cd and Mn were undetectable.The leachate chrome concentration decreased gradually with the increase of lime content,while it decreased at first and then increased with the increase of PFA content.When lime and PFA ratio was 6 ∶ 1,the solidified block had good synergistic solidification effect.