化学沉淀法去除飞灰浸取液中重金属的研究

The removal of heavy metals in fly ash leaching solution by chemical precipitation

采用化学沉淀法去除垃圾焚烧飞灰浸取液中重金属,考察无机与有机重金属沉淀剂种类、加入量及无机与有机重金属沉淀剂联用对浸取液中Pb2+、Cd2+、Zn2+、Cu2+、Mn2+的去除效果。实验结果表明,在选用的无机沉淀剂碳酸钠、硫化钠中,硫化钠的去除效果较好,在硫化钠与重金属摩尔量比为1.5时,总去除率可达87.61%;在选用的有机重金属沉淀剂TMT-102、MT-103与RS-2568中,MT-103对重金属的去除效果最好,在添加量为300 mg·L-1时,重金属总去除率可达97.93%。将无机沉淀剂与有机沉淀剂联用,按照沉淀剂与重金属摩尔量比为1.5加入硫化钠后,再按照添加量为30 mg·L-1添加MT-103,最终溶液中重金属总去除率可高达98.59%,达到很好的去除效果。

The paper studied the removal efficiency of heavy metals in fly ash leaching solution by chemical precipita.tion processes.The effect of inorganic and organic heavy metal precipitant types,precipitant dosage and the combination of inorganic and organic precipitant on the removal rate of Pb^2+、Cd^2+、Zn^2+、Cu^2+、Mn^2+were studied.The results showed that the removal efficiency of sodium sulfide was better than that of sodium carbonate,the total removal rate was 87.61%when the mole ratio of precipitation to heavy metal was 1.5.Of the organic heavy metal precipitants TMT-102,MT-103 and RS-2568 selected,MT-103 had the best removal effect on heavy metals.And the total removal rate of heavy metal was 97.93%when the optimum dosage was 300 mg·L^-1.The inorganic precipitant was combined with or.ganic precipitant,sodium sulfide was added when precipitant and heavy metal mole rate was 1.5.And then MT-103 was added at the optimum dosage of 30 mg·L^-1.The total removal rate of heavy metals in the final solution reached 98.59%,achieving a good removal efficiency.