【摘要】 尾矿库区土壤金属污染严重影响了库区的生态环境,而金属离子在土壤中的危害性大小取决于其进入土壤之后的吸附-解吸、形态转化、迁移等。为了进一步预测和防治土壤金属污染,取某硫铁矿尾矿库区土壤进行室内批淋滤实验,结果表明:淋滤液中金属离子初始浓度越大,越有利于土壤对金属离子的吸附;淋滤液的pH越小,越不利于土壤对金属离子的吸附。土壤对Mn2+的吸附规律更符合双常数方程,对Fex+、Cu2+的吸附规律更符合Elovich吸附速率方程。假设土壤中金属离子可全部溶出,在1∶25土液比的实验条件下金属离子Mn2+、Fex+、Cu2+的持续溶出时间分别为3.28,284.5,1.224d,实际中造成的污染将更加严重。吸附量、吸附速率及分配系数均与淋滤液中金属离子初始浓度及土壤中背景浓度呈正相关关系,土壤中金属溶出时间则与土壤中金属元素背景值呈正相关关系。更多还原

【Abstract】 Metal pollution from tailing soil has seriously impacted the ecological environment of the reservoir area.The hazardous level of metals in soil depends on its adsorption-desorption,transformation,and migration,etc.In this study,batch leaching experiment of pyrite tailing soil was processed for further prediction and control of metal pollution.The results showed that:higher initial concentration of metal ions in drench filtrate was more beneficial for the adsorption of metal ions to soil;low pH of drench filtrate had negative effect on the adsorption of metal ions to soil.Soil adsorption of Mn2+was more in line with the double constant equation,while the Fex+and Cu2+adsorption conformed to the Elovich absorption rate equation.When metal ions in the soil were fully dissoved,the duration pollution time of Mn2+,Fex+and Cu2+was 3.28d,284.5dand 1.224drespectively under a 1∶25solid-liquid ratio,and the actual pollution will be more serious in real cases.Adsorption amount,adsorption rate,and distribution coefficients presented positive correlation with the initial concentration of metal ions in drench filtrate and the background concentration in soil,the dissolution period of metal ions from soil was positively correlated with background values of metal elements in soil.更多还原