混凝法处理垃圾渗滤液水质的生态毒性评价

Ecological Toxicity Assessment on Landfill Leachate Water Quality Treated by Coagulation Sedimentation

采用混凝沉淀法处理强碱性工矿垃圾渗滤液,并通过毒性试验研究了处理前后渗滤液对黑麦草种子萌发及小球藻增殖的影响。混凝沉淀的结果表明,以聚合氯化铝、硫酸铝钾和三氯化铁单独作为混凝剂与助凝剂聚丙烯酰胺混合使用均能有效去除强碱性工矿垃圾渗滤液中总磷和高锰酸盐指数等污染物,其中三氯化铁配合聚丙烯酰胺的去除效果最佳。毒性检测结果显示,不同的混凝沉淀处理方式对黑麦草(Lolium multiflorum)的根系活力无显著影响;在将渗滤液p H预先调至7、每升投加固态聚合氯化铝1.5 g和聚丙烯酰胺0.5g条件下,处理后出水对黑麦草萌发及蛋白核小球藻(Chlorella pyrenoidosa)增殖影响最小,生态安全性最高。

The strong alkaline industrial and mining landfill leachate was treated by coagulation sedimentation, after which toxicity testing was conducted to analyze the effect of the treated and non-treated landfill leachate on Lolium multiflorum seed germination and Chlorella pyrenoidosa proliferation. The results of coagulation sedimentation demonstrated that polyaluminium chloride, potassium aluminum sulfate and ferric chloride respectively as coagulant combined with polyacrylamide can effectively remove the pollutants such as TP and CODMnin the strong alkaline industrial and mining landfill leachate, especially ferric chloride integrated with polyacrylamide had the optimal removal efficiency. Toxicity tests revealed that different coagulation sedimentation treatments had no significant effect on the root activity of Lolium multiflorum. When p H of the leachate was adjusted to 7 and the dosage of polyaluminium chloride and polyacrylamide was respectively 1.5 g/L and 0.5 g/L, the toxicity of the treated leachate had minimal impact on the germination of Lolium multiflorum and the proliferation of Chlorella pyrenoidosa, thus it had the highest ecological security in the three combinations.