雨水作用下铀尾矿中主要污染物的释放特征

Releasing Characteristics of the Main Pollutants from Uranium Tailings Acting with Rain

以广东某铀矿的堆浸尾矿为研究对象,通过静态和动态淋浸实验,研究了雨水作用下铀尾矿中主要污染物的溶出特征和机制.结果表明,尾矿—水作用过程中有大量H^＋、铀（U）和硫酸根离子（SO4^2-）等污染物释放,静态淋浸的浸出液p H变化范围为3.3-3.71,U和SO42-的最大浓度分别为124 mg/L、5.28 g/L;动态淋浸的浸出液p H变化范围为3.34-4.08,U和SO4^2-的最大浓度分别为438.95 mg/L、7.9 g/L.U和SO4^2-的释放前期迅速,后期较缓慢.尾矿表面吸附的铀酰络合物的溶解是导致U快速释放的主要原因.

Static and dynamic leaching experiment were conducted for the heap leaching tailings from Some Uranium Mine, Guangdong, to study the leaching characteristics of the main contaminants from uranium tailings contacted with rain. The results show that quanti- ties of H＋ ,uranium（U） and sulfate ion （SO4^2- ）were released in the process of tailings-water interaction. In the case of static leaching experiment, the pH of leachate ranges from 3.3 to 3.71 ,the maximum concentration of U and SO4^2- are 124 mg/L and 5.28 g/L respectively. In dynamic leaching test, the pH of leachate ranges from 3.34 to 4.08, the maximum concentration of U and SO4^2- are 438.95 mg/L and 7.9 g/L respectively. The release of U and SO4^2- were fast in the initial stage and then became slow. It indicates that the fast release of U is mainly due to the dissolution of uranyl complex absorbed on the tailings surface.