贵州松桃典型锰矿区锰渣重金属污染特征研究

为研究锰矿废渣重金属的污染特征,该文以贵州铜仁松桃典型锰矿区锰渣为研究对象,分析锰渣及浸出液的重金属元素组成、含量及矿物组成,采用Tessier连续萃取法分析锰矿渣中Mn元素的赋存形态。结果表明,锰矿废渣的主要矿物组成为石英砂、白云母、石膏、蒙脱石、高岭土和菱锰矿;通过浸出毒性检测发现浸出液中锰浓度高达8.828 mg/L,是GB 8978—1996《污水综合排放标准》所允许的最高排放质量浓度(2.00 mg/L)的4.4倍;锰矿废渣中Mn元素主要以碳酸盐结合态存在,其次是铁锰氧化物结合态、残渣态、有机态和离子交换态;Mn的生物可利用系数较高,生态风险较大。

In order to study the pollution characteristics of heavy metals in manganese ore slag,the heavy metal element composition,content and mineral composition of manganese slag and leaching solution were analyzed based on the typical manganese slag of Songtao manganese mining area in Tongren,Guizhou Province.The occurrence form of Mn element in manganese slag was analyzed by Tessier continuous extraction.The results show that the main mineral composition of manganese ore waste residue is quartz sand,Muscovite,gypsum,montmorillonite,kaolin and manganite,and the leaching toxicity test shows that the manganese concentration in the leaching solution is as high as 8.828 mg/L,which is 4.4 times higher(2.00 mg/L)than the maximum discharge concentration allowed by GB 8978—1996 Comprehensive Sewage Discharge Standard.Mn element in manganese ore residue mainly exists in carbonate bound state,followed by iron and manganese oxide bound state,residual state,organic state and ion exchange state.Mn has high bioavailability coefficient and high ecological risk.