额尔齐斯河流域及某稀有多金属矿废水铀、钍含量分布及其环境影响

DISTRIBUTION OF URANIUM AND THORIUM IN THE IRTYSH RIVER AND UPRIVER WASTEWATER FROM A RARE MULTI-METAL MINE

运用简易、快捷、灵敏的ICP MS法直接测定稀有多金属矿以及河水样品中的铀钍含量,并推算其与比放射性活度之间的定量关系,客观评价了某稀有多金属矿废水中的放射性水平以及额尔齐斯河流域的放射性污染现状。研究表明,某稀有多金属选矿废水铀含量可达78 311μg/L,钍含量达0 627μg/L。额尔齐斯河流域各支流河水铀、钍平均含量分别为0 584μg/L、0 025μg/L,其干流河水钍平均含量为0 019μg/L,而铀平均含量达2 234μg/L,远高于世界河水铀平均含量0 309μg/L。

The contents of U and Th in water samples from the Irtysh River and wastewater from a rare multi-metal mine have been detected directly by ICP-MS. According to the isotopic composition of the elements, the quantitative relationship between the contents of radioactive elements in water and specific activity has been deduced. Then we have evaluated the environmental radioactive pollution status of the Irtysh River and wastewater from the rare multi-metal mine. U and Th contents in wastewater from the rare multi-metal mine are 78.311 μg/L and 0.627 μg/L, respectively. The average contents of U and Th in water from the branches of the Irtysh river are 0.584 μg/L and 0.025 μg/L, respectively. In water from an Irtysh trunk stream, Th average content is 0.019 μg/L while U is up to 2.234 μg/L, which is much higher than the average content of 0.0309 μg/L in water from global rivers.