某酸法地浸铀矿山氡释放特征研究

Investigation on Radon Release Characteristics of an Acid In-situ Leaching Uranium Mine

以某酸法地浸铀矿山为对象,开展了酸法地浸采铀源项氡浓度、氡释放量,以及环境氡迁移扩散趋势等释放特征研究。采用E-Perm驻极体探测器法、固体径迹探测器法、RAD7静电收集测氡法,对地浸铀矿山抽液孔、集液罐、水冶厂通风口、蒸发池源项及周边环境的氡浓度进行了监测。结果表明,该地浸铀矿山氡释放量约为1.75 TBq/a,水冶厂通风口和集液罐是重要的氡释放源项,其年氡释放量分别占地浸铀矿山年氡释放量的58%和39%;抽液孔和蒸发池的年氡释放量约占地浸铀矿山年氡释放量的3%;集液罐开口处氡浓度水平最高,其对环境影响范围不超过500 m;抽液孔氡浓度水平最低。该酸法地浸矿山归一化氡释放量远小于地下矿山排风井的归一化氡释放量。

Investigation on release characteristics of radon concentration,radon release amount,migration and diffusion trend of radon of an acid in-situ leaching uranium mine was carried out on the basis of data collection and field investigation.This study monitored radon concentration of source items and surrounding environment on uranium milling plant vents,leaching tanks,evaporation ponds and recovery wells with adoption of E-Perm electret detector,solid track detector and RAD7 radon detector.The results show radon concentration level is highest at top opening of leaching tanks,nevertheless affected area is no more than 500 m.Lowest radon concentration appeare at point of recovery wells.The annual total radon release of the acid in-situ leaching uranium mine is about 1.75 TBq/a,milling plant and leaching tanks are important radon release source items,which accounte for 58%and 39%of the total radon release respectively,additionally radon release of recovery wells and evaporation ponds account for 3%of the total radon release.In summary,the normalized annual radon release amount of the acid leaching uranium mine is much smaller than that of underground mine exhaust shaft.