生物炭对重金属污染沉积物的修复效果

发布时间：2018-07-05 16:13

本文选题：重金属 + 沉积物　；参考：《环境化学》2016年12期

【摘要】：采用1%、2%和5%的生物炭钝化污染沉积物中的重金属,并研究生物炭修复对水体的生态影响.结果表明,生物炭添加后水体的p H值显著增大,上覆水和间隙水中溶解态Cu、Zn和Cd浓度均显著降低.1%(W/W)生物炭添加量使上覆水中溶解态Cu比对照降低了82.4%;在不同添加量下间隙水溶解态Zn降低幅度为11.7%—62.8%.通过BCR重金属形态分级发现沉积物中酸溶态重金属均有向残渣态转化的趋势.在5%生物炭添加量时,酸溶态Cu降低了73.08 mg·kg-1,降低幅度达到32.1%,而可氧化态Pb增加幅度达到67.8%.通过生物可利用实验(PBET)发现,当生物炭添加量为5%时,生物可利用性Cu降低9.8%,Zn、Pb和Cd的生物可利用性也有不同程度降低.生物炭添加到沉积物后,用于植物毒性试验的家独行菜(Lepidium sativum)茎长呈现19.5%—25.7%的增加,根长也随之增加,说明生物炭降低了沉积物重金属的植物毒性.
[Abstract]:The heavy metals in sediments were passivated by 2% and 5% biochar, and the ecological effects of biochar remediation on water body were studied. The results showed that the pH value of the water increased significantly after the addition of biochar. The concentration of dissolved Cu Zn and CD in overlying water and interstitial water decreased significantly by 0.1% (W / W), the dissolved Cu content in overlying water was 82.4% lower than that in the control, and the range of dissolved Zn in interstitial water decreased by 11.7-62.8%. It was found that the acid soluble heavy metals in the sediments had the tendency to transform to the residual state by BCR heavy metal speciation classification. At the addition of 5% biochar, the acid soluble Cu decreased by 73.08 mg / kg ~ (-1) and decreased by 32.1 mg 路kg ~ (-1), while the oxidizable Pb increased by 67.8 mg 路kg ~ (-1). Through the bioavailability experiment (PBET), it was found that the bioavailability of Cu decreased by 9.8%, and the bioavailability of Zn, Pb and CD decreased in varying degrees when the amount of carbon added was 5. After the addition of biochar to the sediment, the stem length of Lepidium sativum was increased by 19.5- 25.7%, and the root length was also increased, which indicated that the biochar reduced the phytotoxicity of heavy metals in sediments.
【作者单位】：华中农业大学资源与环境学院;
【基金】：国家自然科学基金(50809030)资助~~
【分类号】：X52

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