贵州煤矿集中开采区地表水重金属污染特征

The characteristics of heavy metals pollution in surface water at the intensive coal mining area in Guizhou

对贵州煤矿集中开采区地表水重金属污染情况进行评价,掌握重金属污染迁移特征,采用数理统计分析、Pearson相关性分析以及综合污染指数评价法对贵州省摆沙河流域煤矿区周边13个监测点共9项污染指标进行评价分析.结果表明,该区域地表水中总铁、锰、铝和汞的富集程度较高,浓度均值分别为68.48、2.75、9.91 mg·L-1和0.0035 mg·L-1,均超出了地表水质量标准限定值,且汞超标率高达100%.总铁、锰、铬、铝、锌属于高度变异,部分地区污染严重,且区域性极强,污染情况随矿区位置不同而呈现显著差异.总铁、锰、铝、锌之间具有较显著的正相关关系,表明该4种污染物质来源一致或相似,总铁及铝均与pH呈强负相关性,说明pH影响重金属的浸出性能.13个地区中毛坡栗(G8)污染程度较轻,新寨2(G2)、陆家桥(G13)为重度污染,其他10个监测点均为严重污染,其中翁威主矿处(G4)污染最为严重;总铁、锰、汞的影响权重值较高,新寨1(G1)、翁威主矿处(G4)、两岔河(G6)、楼梯冲(G7)、瓦厂河(G9)总铁、锰污染程度较高,新寨2(G2)、翁威2(G5)、豆芽井(G10)、上坝(G11)、蛋托厂(G12)、陆家桥(G13)地区受汞污染影响严重.

In order to evaluate the heavy metals pollution in surface water in coal concentrated mining area of Guizhou, and achieve the characteristics of heavy metals pollution and migration, mathematical statistical analysis, pearson correlation analysis and comprehensive pollution index evaluation method were used to evaluate and analyze the 9 pollution indexes in 13 monitoring sites around the coal mining area in Baisha River Basin, Guizhou. The results showed that the concentrations of total iron, manganese, aluminum and mercury in the surface water in this area were high, with the average concentrations of 68.48, 2.75, 9.91, 0.0035 mg·L-1, respectively, which was above the standard of surface water environment quality. Particularly, 100% mercury concentrations were higher than the standard. Total iron, manganese, chromium, aluminum and zinc were highly variable and regional. Their concentrations varied with the monitoring sites, and some areas were seriously polluted. There was a significant positive correlation among the concentrations of total iron, manganese, aluminum and zinc, indicating that the sources of the four pollutants were same or similar. Moreover, the concentrations of total iron and aluminum were negatively correlated with pH, indicating pH affected the leaching performance of heavy metals. In 13 monitoring areas, Maopoli(G8) was less polluted, but Xinzhai2(G2) and Lujia Bridge(G13) were severe polluted, and the other 10 monitoring sites were all serious polluted, in which Wengwei main Mine(G4) was the most polluted area. The weight values of total iron, manganese and mercury were high. The pollution of total iron and manganese in Xinzhai1(G1), Wengwei main mine(G4), Liangcha River(G6), Loutichong(G7), Wachang River(G9) were serious. Xinzhai2(G2), Wengwei2(G5), Douya Well(G10), Shangba(G11), Egg carton factory(G12) and Lujia Bridge(G13) were seriously affected by the mercury pollution.