多组分离子交换吸附反应-运移的土柱试验及模拟

Column experiment and simulation on multi-species cation exchange reactive transport

利用室内一维饱和垂直土柱对保守性溶质运移和反应性溶质运移分别进行了试验,并用水文地球化学模拟软件PHREEQC模拟了保守性溶质Cl-的运移以及K+、Ca2+、Na+、Mg2+4种主要阳离子的反应运移过程,分析了土壤中发生的离子交换吸附和盐分运移过程,进一步模拟分析了不同入流溶液种类、次序以及有无置换反应情况下出流溶液的差别。结果表明:这些条件的不同均会对出流溶液的种类和浓度产生明显影响,表明水文地球化学反应对地下水中污染物的迁移会产生很大影响,在相关领域的研究中不宜忽略。

Cation exchange is one of the major reactions in polluted soil.Laboratory experiment was employed in a vertical soil column to test conservative solute transport and reactive solute transport,respectively.Hydrogeochemical simulation software PHREEQC was applied to simulate the conservative solute transport and reactive solute transport of K ＋,Ca2 ＋,Na ＋,Mg2 ＋.Good comparison of experimental and simulation results indicate that the software can effectively simulate cation exchange and solute transport occurring in soil.Further simulations were carried out to study the influence of different inflow solutions and their sequences,and the influence of exchange reaction on the outflow.Results show that all these factors have a great influence on the species and concentration of outflow.Hydrogeochemical reaction exerts a great influence on transport of pollutant in groundwater and should not be neglected in related researches.