原位臭氧化处理非饱和土壤中的难解有机污染物

In situ ozone remediation, one of the novel technologies of soil remediation, was studied in this project to overcome the drawbacks of the present remediation strategies. Ozone remediation can be employed alone, or combined with bioremediation. The effect of various conditions on ozone remediation was investigated using coluimn experiment and mathematical modeling. The variation of bioavailability and biodegradability of PAHs in the soil was studied during ozone remediation. A microscopic model was proposed to simulate in situ ozonation for the remediation of hydrophilic compound such as 2-chlorophenol and hydrophobic compound such as phenanthrene. It showed that ozone could destruct PAHs in the soil quickly. The removal efficiency of PAHs increased with the increase of time, ozone concentration and ozone mass transfer coefficient, but decreased with the increasing soil moisture content. The soil contaminated with more PAHs needs more time to remediate. The gas flow rate and rate constant of ozonation had little effect on ozone remediation within the certain range. The bioavailability and biodegradability of PAHs was improved after ozone treatment. The proposed microscopic model fitted data well during most time of remediation. This study provided the basis for the application of in situ ozone remediation.

研究原位臭氧化处理非饱和土壤中难降解有机污染物的反应机理，即气相臭氧的气液传质机理、固相污染物的固液传质机理、水相臭氧化机理以及臭氧化反应和传递过程之间相互作用机理，并建立相应的数学模型。同时考察臭氧化过程地对土壤生态系统的影响，为该技术的单独使用或与生物修复相结合净化污染土壤提供理论依据。