锑矿区水体水环境锑污染及硫同位素示踪研究

Antimony Pollution and Sulfur Isotope Study in the Waters of an Antimony Mine area

本文系统研究了贵州省半坡锑矿区水环境锑污染现状,用硫同位素指示采矿活动对矿区水体的影响,以查明锑矿区水环境中Sb的释放迁移过程和水污染程度。研究发现,矿区水体中Sb和SO42-含量分别高达1377μg/L和1926 mg/L;岔河下游近10 km处仍保持较高水平(182.5μg/L Sb和59.8 mg/L SO42-)。岔河水体中,δ34S-Sb、δ34S-SO42-和Sb-SO42-间均具显著正相关,相关系数分别为r=0.68(p<0.05)、r=0.89(p<0.01)、r=0.72(p<0.05)。表明岔河水体中,δ34S和SO42-能很好地指示矿业活动引起的Sb污染程度和扩散范围。根据同位素质量平衡原理估算,发现矿区下游水体中的硫主要来自矿山,表明矿区下游水体污染受采矿活动影响显著。

This study investigated the pollution state of antimony in the waters of an antimony mine located in Banpo,Guizhou Province,and traced the pollutants using sulfur isotope.The main goals of this study are to clear the geochemical progresses controlling the fate and the transfer of antimony and to better understand the current pollution state of the rivers in this antimony mine area.The results showed that the waters are suffering from serious pollution with Sb and SO2-4 concentrations being up to 1377 μg/L and 1926 mg/L,respectively.The downstream water of the Chahe River,10 km away from the mine area,still contains high concentrations of Sb and SO2-4.In Chahe River,δ34S-Sb,δ34S-SO2-4 and Sb-SO2-4 are remarkably positively correlated,the correlation coefficients are r=0.68（p0.05）,r=0.89（p0.01） and r=0.72（p0.05）,respectively.These positive correlations suggest that δ34S in the dissolved sulfate and the concentration of SO2-4 can well reflect the water pollution state and the diffusion distance of antimony in the Chahe River.According to the calculation of isotope mass balance,the sulfur in the downstream of the mine area are mainly form antimony deposit,which implies that the water quality in the mine area is significantly affected by mining activities.