甲苯在渗流区的生物通风去除模拟

建立了数学模型来描述生物通风过程中渗流区土壤中甲苯的运移和生物降解过程,模型考虑了对流通量、扩散通量、相间传质和生物降解项,模型中的生物降解参数由独立间歇实验用Levenberg Marquardt方法确定.在实验室中用土柱实验来模拟生物通风过程,结果显示,实验数据与模型比较吻合,经过50h后,约有98%的甲苯已被去除.利用土柱尾气中甲苯实验数据和质量衡算式计算可得:挥发去除的甲苯占初始加入甲苯的53 78%,生物降解去除的甲苯为42 92%,土壤中残余甲苯浓度为2 56mg·kg-1.

The simulation of removal of toluene by bioventing in the vadose zone

The transport and biodegradation of toluene in the vadose zone could be quantitatively described with a mathematical model, which considered the advective flux, diffusion, interphase mass transfer and biotransformations. The microbial parameters were determined by Levenberg-Marquardt method in the independent batch experiments. The soil column was used to simulate the bioventing. Results showed that the model was well fitted with experimental data. After 50h, 98% of the toluene was removed. With the data of toluene in offgas and mass conservation equation, we obtained that toluene removed by volatilization and biodegradation were 53.78% and 42.92% respectively, and the residual toluene in the soil was 2.56mg·kg^-1.