【摘要】 在25℃,污泥浓度20 g/L条件下,以硫酸铁为萃取剂对两种污泥(W1&W2)进行重金属浸出研究.结果表明,向污泥中投加硫酸铁能导致污泥酸化和污泥中重金属的溶出.投加量越大,污泥pH值降得越低,重金属的溶出率也越高.向W1中投加按Fe3+计算为1.5 g/L硫酸铁时,其pH值降至3.02,Cd,Cu,Zn溶出率分别可达到82.5%,70.9%和89.0%;向W2中投加4.5 g/L Fe3+,其pH值降至3.19,Cd,Cu,Zn的溶出率分别可达到80.0%,88.2%和92.1%.在相同pH条件下,Fe3+比硫酸能更有效浸出污泥中重金属;用Fe3+浸提污泥中重金属能达到与生物淋滤法同等的溶出效果,并缩短了反应时间.用Fe3+浸出污泥中重金属具有一定可行性.更多还原

【Abstract】 The removal of heavy metals from two different kinds of sewage sludge（W₁ & W₂） was conducted by using ferric sulfate at 25 ℃,and the sludge solid concentration was 20 g/L.It was found that the addition of ferric sulfate to the sludge caused the acidification of the tested sludge and the dissolution of heavy metals from the sludge.The pH of the sludge decreased and the removal percentage of heavy metals increased with the increase of the amount of ferric sulfate added.For W₁ the best amount of ferric ion added was 1.5 g/L with a low pH value 3.02 and high removal percents of Cd,Cu,Zn,which were as follows: 82.5%,70.9%,89.0% respectively;while for W₂ the best amount of ferric ion was 4.5 g/L and the pH value was 3.19 and the removal percentage of heavy metalsCd,Cu,Zn were 80.0%,88.2%,92.1% respectively.Ferric iron dissolved Cd,Cu,Zn from the sludge more effectively than sulfuric acid at the same pH value.The removal percentage of Cd,Cu and Zn using ferric sulfate was equivalent to that by bioleaching and shortened the experiment time.更多还原