【摘要】 采用土柱淋溶实验方法对多环芳烃(PAHs)在人工污染土柱中表面活性剂淋溶下的运移进行了实验室研究,获得了示踪剂Br- 和PAHs的穿透曲线(BTCs) ;并通过室内批量平衡试验(PAHs和表面活性剂吸附试验和表面活性剂对PAHs吸附 解吸影响试验)获得了吸附系数,进而获得阻滞因子.基于这些实验室结果,通过CXTFIT2. 1软件,用平衡CDE模型拟合了Br- 的BTCs,获得物理和水动力参数;并在此基础上应用CDE非平衡模型拟合PAHs在表面活性剂淋溶条件下土柱中的BTCs以及不同时刻、不同埋深处PAHs浓度的动态变化,预测了PAHs在土柱中的迁移趋势.更多还原

【Abstract】 Polycyclic Aromatic Hydrocarbons (PAHs) transport behaviors in soil column when surfactant (LAS) worked as the leaching solvent were studied. By the soil column experiments, the breakthrough curves (BTCs) of the tracer bromide (Br-) and PAHs were obtained. The batch equilibrium experiments were conducted to achieve the absorption coefficients, and then the retardation factor (R) was calculated. A nonlinear least-squares optimization approach (CXTFIT 2.1) was used to fit BTCs of Br- and PAHs. The symmetrical BTC for Br- was best described by the equilibrium CDE model, and then the physical and hydrodynamic parameters from the fitting result were obtained, i.e. the dispersion coefficient (D). Based on these, the equilibrium and non-equilibrium CDE models were applied to fit the asymmetrical and tailing BTCs of PAHs. The comparison showed that two-site CDE model best fitted the observed data. The trends of PAHs transport at different time and depth in the soil column was also estimated using two-site CDE model.更多还原