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石煤钒矿开采过程中的大量废石,由于露天堆放而导致周边环境产生重金属污染。以湖北某地石煤钒矿废石为研究对象,通过进行实验室静态淋溶试验发现,淋出液中V,Pb,Cd,Cr,As溶出量随粒度的增加而降低,最高溶出量分别为7695.00,1266.00,19.10,777.70,163.10μg·kg~(-1),重金属溶出率分别达到0.23%,11.71%,0.18%,0.12%,1.00%。研究发现,淋出液p H值对重金属溶出量影响较大,高p H值会使重金属沉淀吸附于废石表面,从而降低淋出液中重金属浓度,对环境污染程度较低。石煤钒矿废石的淋溶过程按淋出液p H变化规律可分为4个阶段,分析各阶段主要反应为:碱性矿物溶解和H+与基本阳离子交换作用、硫铁矿等还原性矿物氧化产酸作用、硅酸盐矿物的风化作用和金属元素的吸附沉淀作用。
A large amount of waste rock during the mining process of stone coal vanadium mine resulted in heavy metal pollution in the surrounding environment due to the piled up in the open air. Taking the stone, vanadium ore and waste rock of a certain place in Hubei as the research object, through the static leaching test in the laboratory, it was found that the leaching amount of V, Pb, Cd, Cr and As in the leachate decreased with the increasing of the granularity, The results showed that the dissolution rates of heavy metals reached to 0.23%, 11.71%, 0.18%, 0.12% and 1.00% respectively for 7695.00,1266.00, 19.10,777.70,163.10μg · kg -1. The results showed that the p H value of leachate had a great influence on the leaching of heavy metals, and the high p H value would adsorb heavy metal on the surface of waste rock so as to reduce the concentration of heavy metals in the leachate and lower the environmental pollution. The leaching process of waste rock from the stone coal vanadium ore can be divided into four stages according to the change law of the p H of the leachate. The main reactions in each stage of the analysis are: alkaline mineral dissolution and H + exchange with basic cations, reducibility of pyrite Mineral oxidation and acid production, weathering of silicate minerals and adsorption and precipitation of metal elements.