西南某省14种尾矿重金属浸出量及总量分析

Analysis on the Heavy Metal Leaching and Content of 14 Types of Tailings in a Certain Southwestern Province

研究中国西南某省不同类型尾矿的重金属浸出量及总量,为尾矿的污染防范、环境管理和综合利用提供参考和建议。采集了14种类型共164个有代表性尾矿进行浸出毒性试验,并分析其中79个典型尾矿样品的9种重金属含量,以评估其污染风险和综合利用价值。结果表明,有5种类型共7个样品出现浸出毒性超标,分别为铅锌矿、镍矿、银矿、铁矿、锰矿,总体超标率为4.3%。超标元素分别为砷、镉、锌、铅、铜、镍等6种元素,最大超标倍数分别为砷18.3倍、锌4.8倍、镉3.0倍、铅0.56倍、铜0.32倍、镍0.16倍;尾矿含有较多重金属,其中砷、锌、铅、铜含量较高,最高分别达到11.75%、2.60%、1.01%、0.29%,不同类型尾矿其重金属含量各有不同,铅锌矿尾矿的重金属总量最高。总体上,该省绝大多数尾矿为普通固废,少部分为危险废物,砷、镉、锌、铅、铜、镍等6种元素存在污染风险,其中砷元素是最主要污染物;尾矿由于重金属含量较高而有一定的综合利用价值。

The heavy metal pollution risk of different types of tailings were investigated for suggestions of comprehensive utilization, environmental management, and pollution prevention of tailings. Collecting 14 types of 162 representative tailing samples from a southwestern province in China, leaching tests for toxicity evaluation was then conducted, while 9 heavy metals content of 79 samples were determinated, to evaluate the pollution risk and comprehensive utilization value. Results showed that there were 7 samples, 5 types of gold, nickel, silver, iron and manganese tailings, exceed standard of leaching toxicity, the overall exceeding standard is 4.3%. The exceeding elements and the biggest exceeding standard times respectively are As, 18.3 times , Zn, 4. 8 times, Cd, 3.0 times, Pd, 0. 56 times, Cu, 0. 32 times, Ni, 0. 16 times. There were much metal in tailings, the highest concentrations of As, Zn, Pd, Cu are 11.75% , 2. 60% , 1.01% ,0. 29% respectively. Heavy metal content in different types of railings were various, while lead-zinc mine tailing contain highest heavy metals content. Conclusion was made that the most tailings collected from the province south-western china were ordinary solid waste, while a small part of samples were hazardous wastes. And 6 metals（As, Pd, Cu, Zn, Cd and Ni） were pollution hazard, while As was the main pollutant. tailings have comprehensive utilization value to some extent due to its heavy metals content.