矿井水铬污染的实验研究——以徐州-大屯矿区为例

Experimental Study of Chromium Pollution in Coal Mine Water:A Case of the Xuzhou-Datun Coal Mine District,Jiangsu,China

煤矿矿井水中的重金属元素Cr对人体和环境具有危害。以徐州-大屯矿区为研究对象,采用淋滤模拟实验等方法,对煤层及其顶底板岩石中Cr的溶出行为及矿井水Cr污染潜势进行了研究.结果表明,煤层顶板渗透水中Cr的质量分数远高于煤浸泡水中其质量分数,表明顶底板岩石具有更高的Cr污染潜势;矿井水中Cr主要来源于煤层顶底板中伊利石向高岭石的转化;环境pH值对矿井水中Cr的含量起到控制作用,pH值、Eh值及温度对Cr的溶出行为产生影响.Cr的溶出量在中性条件下较小,在酸性或碱性条件下比中性条件下高出一个数量级以上。较高的环境Eh值和环境温度将加速Cr的溶出.

Chromium （a trace heavy metal element） in coal mine water is harmful to human health and environment. The dissolvable behavior of the chromium from the coal seams and roof/floor rocks and the pollution potential to the coal mine water were investigated by a leaching experiment taking the Xuzhou-Datun coal mine district, Jiangsu, China, as a case. The results show that the chromium concentration in the leachate from the roof and floor rocks was much higher than that from the coat seams, which indicates that the rocks have higher pollution potential. Chromium in the coal mine water was resulted from the transformation of illite to kaolnite in the rocks. The concentration and dissolvable behavior of the chromium were affected by the pH, Eh and temperature of the water. Chromium leaching was weak under neutral water medium, while one or two magnitude higher under acid or alkaline conditions. The higher Eh and temperature of the water may promote the chromium leaching.