Influence of amendments and aided phytostabilization on metal availability and mobility in Pb/Zn mine tailings

A greenhouse experiment was conducted to evaluate the effect of four different amendments, bone mill, bottom ash, furnace slag, and red mud, as immobilizing agents and the plant species Miscanthus sinensis and Pteridium aquilinum in aided phytostabilization of Pb/Zn mine tailings. The effects of amendments and plants on the availability and mobility of heavy metals were evaluated using single extraction, sequential extraction, pore-water analysis, and determination of heavy metal concentrations in plants. The application of Fe-rich amendments significantly reduced the amount of soluble and extractable heavy metals in the tailings (p < 0.05). Furnace slag and M. sinensis reduced CaCl2-extractable heavy metals by 56-91%, red mud and P. aquilinum treatment was the most effective at decreasing bioaccessible Pb, reducing it to 34% of the total Pb. Compared to control, water soluble Cd, Cu, Pb, and Zn were reduced by 99, 99, 98, and 99%, respectively, in the red mud and R aquilinum tailings. M. sinensis accumulated heavy metals mainly in the root, and had lower translocation factors compared with P. aquilinum. The results of this study suggest that M. sinensis can be used in aided phytostabilization for these types of mine tailings and Fe-rich amendments are effective for the in situ immobilization of metals. (C) 2014 Elsevier Ltd. All rights reserved.

进行了一项温室实验，以评估骨粉、底灰、炉渣和赤泥这四种不同改良剂作为固定剂以及植物种类芒草（Miscanthus sinensis）和蕨菜（Pteridium aquilinum）在铅锌矿尾矿辅助植物稳定化中的作用。通过单一提取、顺序提取、孔隙水分析以及测定植物中重金属浓度，评估了改良剂和植物对重金属有效性和迁移性的影响。富铁改良剂的应用显著降低了尾矿中可溶性和可提取重金属的含量（p < 0.05）。炉渣和芒草使氯化钙可提取重金属减少了56 - 91%，赤泥和蕨菜处理在降低生物可利用铅方面最为有效，使其降至总铅的34%。与对照相比，赤泥和蕨菜尾矿中水溶性镉、铜、铅和锌分别降低了99%、99%、98%和99%。芒草主要在根部积累重金属，与蕨菜相比，其转运系数较低。本研究结果表明，芒草可用于此类矿尾矿的辅助植物稳定化，富铁改良剂对金属的原位固定是有效的。（C）2014爱思唯尔有限公司。保留所有权利。