摘要
为了更好的防止岩溶灾害的发生,研究了不同温度条件下盐酸盐溶液对石灰岩和白云岩侵蚀规律。应用美国地质调查所开发的水化学模拟软件Phreeqc对在不同CO2分压下,不同浓度的NaCl和MgCl2溶液中的方解石和白云石的溶解度和温度的关系进行了水化学模拟并进行了实验验证。研究结果显示,在NaCl溶液中,方解石和白云石溶解度均大于在纯水中的溶解度;方解石在MgCl2溶液中的溶解度大于在同条件下NaCl溶液中的溶解度;无CO2分压的情况下,在同浓度的盐溶液中,方解石和白云石的溶解度随着温度的升高迅速升高;在pco2=10-4.5MPa时,方解石和白云石溶解度随着温度的升高而降低,然而始终大于在无CO2分压时的溶解度。在岩溶塌陷区,在与大气联系非常小的地下水系统中,温度的升高能够增强对岩体的侵蚀,从而使塌陷的危险增大;在与大气联系非常紧密的地下水系统中,温度降低(大于0℃)能够增强对岩体的侵蚀,从而使塌陷的危险增大。
In order to prevent karst disaster,the paper researched the influence of dissolving degrees of limestone and dolomite caused by temperature in hydrochloride solution.A water chemistry simulation software-phreeqc developed by American Geological Investigation Institute was used,the relation model between temperature and dissolving degrees of calcite and dolomite was simulated under different CO2 pressure and different concentration NaCl and MgCl2solution,which was tested by experiment.The results indicated that dissolving degrees of calcite and dolomite in NaCl solution is larger than that in pure water;The dissolving degrees of calcite in MgCl2solution is larger than that in NaCl solution under same condition;without CO2 pressure,in the same concentration salt solution,the dissolving degrees of limestone and dolomite increased rapidly with temperature;While pco2 =10-4.5 MPa the reverse happened,but it is larger than that without CO2 pressure.In karst collapse area,the erosion of rock improved with temperature increasement,which caused increasement of the danger degree of collapse in groundwater system which have no obvious relationship with atmospheric;while the erosion of rock increased with reducing temperature（larger than 0℃）,so as to enhunce the danger degree of collapse in groundwater system.
出处
《水资源与水工程学报》
2011年第4期21-24,30,共5页
Journal of Water Resources and Water Engineering
基金
国家自然科学基金资助项目(50874102)
国家自然科学基金资助项目(50974070)的部分研究成果
