土壤电动修复中菲迁移的数值模拟

In order to address the problem of repairing phenanthrene-contaminated soil, both laboratory simulation and experiments were conducted to study the phenanthrene migration in soil under electrodynamics. Electroosmotic flow, electromigration, convection, and dispersion were determined to be the four main processes to affect phenanthrene migration. A phenanthrene migration model in contaminated soil under electrodynamics was established. The phenanthrene migration process was simulated using COMSOL Multiphysics 5.3 software, the migration equations and the selected parameters. Results showed that at the porosities of 0.330, 0.380, 0.430, and 0.480, the maximum mobility of phenanthrene were 31.9%, 34.8%, 38.0% and 41. 7%, respectively. As the voltage increased from 0.500 V•cm^-1 to 2.00 V•cm^-1, the electroosmotic flux increased accordingly, resulting in a maximum mobility of 44.4%. In the remediation area, a bowl-shaped distribution occurred for the phenanthrene concentration. The simulation calculation determined that phenanthrene concentration reached a minimum value of 2.14 mol•m^-3 in the middle region close to the anode, and the maximum mobility was 38. 0% accordingly. The simulated results for phenanthrene migration and distribution were in a good agreement with the experimental results, which verified that the applicability of the developed model in the electrokinetic remediation of soil contaminated by polycyclic aromatic hydrocarbon.