湘西金矿尾矿-水相互作用:2.动力学模拟

从硫化物的氧化、脉石矿物的溶解、氧的扩散、水的流动和溶质质量迁移等过程的耦合作用建立了尾矿-水相互作用的动力学模型。对湖南湘西金矿尾矿库的数学模拟表明：早期尾矿-水的相互作用可以引起酸水的产生和重金属的释放及对环境的污染，影响较大的主要是前30年，随着时间增加，尾矿孔隙水逐渐中性化，污染元素含量显著降低。脉石矿物的溶解和有机物反应可降低尾矿中氧的扩散和产生酸的中和作用。尾矿库上部孔隙水中各组分含量明显高于尾矿库下部，并在约6m深处存在突变带。尾矿库的水文分带是导致地球化学分带的主要原因。

TAILINGS-WATER INTERACTION IN XIANGXI GOLD MINE, HUNAN PROVINCE,CHINA:Ⅱ.DYNAMIC MODELING

Based on the coupled processes among sulfide oxidation, gangue dissolution, oxygen diffusion, water flow and mass transport, this paper established a comprehensive dynamic model for tailings-water interaction. Mathematic modeling for tailings impoundments in the Xiangxi gold mine, Hunan Province, China, showed that tailings-water interaction would release acid and heavy metals to pollute environments at the early stage. Greater impact on environment can last for 30 years. Pore-water in tailings can be neutralized progressively and the contents of polluted species tend to decrease markedly with time. Gangue dissolution and organic matter reaction can result in acid-neutralization and a decrease in diffusion of oxygen in tailings impoundments. The contents of pore-water species in upper tailings are much higher than in lower tailings, and vary abruptly at the 6-m depth. Hydrological zoning in tailings impoundments is the main reason for geochemical zonation.