硫酸水对方解石和白云石矿物的溶蚀作用

结合自然界实际存在的特殊岩溶现象,对硫酸水的产生及其对方解石、白云石溶蚀的水化学机理进行了分析。认为金属硫化矿物氧化、酸雨、工业污水排放以及火山活动、岩浆入侵、热液作用等均可产生硫酸,这些硫酸与天然水混合后形成硫酸水。通过模拟计算显示水中1mol硫酸可溶解方解石1.80~2.12mol或白云石0.92~1.09 mol。分析该反应过程的水化学作用包括H+的作用、次生CO2、盐效应、同离子效应、离子对的作用、白云石化和去白云石化作用等。硫酸水存在的岩溶区岩溶发育异常强烈,而大的溶蚀空隙又加剧了地下水的循环交替作用,混合后的水对碳酸盐岩常具有较强侵蚀性,这两种作用均可促使岩溶进一步发育。

Corrosion of calcite and dolomite in sulfuric acid water

The generation of sulfuric acid water and the hydro-chemical mechanism of corrosion of calcite and dolomite mineral in sulfuric acid water are analyzed. Sulfuric acid may be produced by the oxidation of metal sulfide, acid rain, industrial sewage discharge, volcanic activity, magma, hydrothermal solution effects, and so on. Sulfuric acid mixed with natural water will form sulfuric acid water. It was found from simulation that one mol of sulfuric acid may dissolve 1.80 to 2.12 mol of calcite or 0.92 to 1.09 mol of dolomite in water. Its hydro-chemical mechanisms include the functions of H^＋ and secondary CO2, salt effects, common-ion effects, ion pair effects, and dolomitization and dedolomitization effects. In karst areas with sulfuric acid water, the karst development is often very strong, and large corrosion gaps aggravate the circulation of the groundwater, the mixture of which with sulfuric acid water has strong erosive effects on carbonate rocks. These two roles can further promote the development of karsts.