硫化矿尾矿堆的温度变化和动态淋溶规律研究

Study on Temperature Change and Dynamic Leaching Law of Sulfide Ore Heap

为研究硫化矿尾矿对环境的潜在影响和危害 ,采用硫化矿尾矿直接浸润实验 ,研究了硫化矿尾矿堆放中内部温度的变化特性 ;利用动态柱式淋溶实验 ,研究了硫化矿尾矿在不同淋溶条件下的铅锌重金属离子溶出规律。结果表明 ,硫化矿尾矿堆的内部温度随堆放时间的延长而升高 ,到第 2 5～ 30天时达到最高值 ;浸润液的pH值对尾矿堆内部温度存在显著影响 ,酸性越强 ,尾矿堆内部温度越高。在酸性、碱性动态淋溶条件下 ,铅、锌离子都有一定的溶出浓度 ,酸性越强 ,越有利于离子溶出 ,离子溶出浓度随淋溶时间延长而降低 ;与Pb2 + 相比较 ,Zn2 + 的溶出受淋溶液pH值及淋溶时间的影响更大 ,对强酸性淋溶很敏感。此外 ,尾矿对不同淋溶液的pH值有较强的缓冲能力 ,只有较强酸度和较长时间的淋溶时 。

To assess the potential impact and danger of sulfide tailings to the environment, experiments were made on direct soaking of sulfide tailings for studying the characteristics of change in the heap temperature of sulfide tailings during deposition. Dynamic lysimetric experiments were made for studying the heavy metal ion release law of sulfide tailings under different conditions. The resulte showed that the heap temperature of sulfide tailings inoreased with the increase of deposition time and reached maxium on the 25th to 30th day. The pH value of soaking solution had evident effect on the heap temperature, and the stronger the solution acidity was, the higher the heap temperature would become .Under both acidic and alkaline conditions of dynamic leaching, lead and zinc ions could be leached out in certain degree. The stronger solution acidity was more favourable for the ion release and the released ion concentration would decrease with the increase of leaching time. Compared to Pb 2+ , the release of Zn 2+ was more sensitive to the solution pH value and the leaching time, especially in strong acidity leaching .Besides, sulfide-mine tailings had rather strong buffering ability to the change of solution pH value, which could be weakened only in strong acidity and long-time leaching.