表面活性剂冲洗修复多氯联苯污染土壤多相流研究

多氯联苯(PCBs)是一种具有持久性、抗生物降解性、脂肪溶性和明显的生物毒性等特性的持久性有机污染物,PCBs在土壤中难于准确定位、难被分解和强烈吸附,去除土壤中PCBs比较困难.表面活性剂冲洗法可以通过提高PCBs溶解度和降低水-PCBs界面张力来实现PCBs从土壤中去除;表面活性剂冲洗PCBs污染土壤涉及气相、水相、NAPLs相和固相等物质,是多相共存并相互发生作用的过程,发生相对渗透率、饱和度和毛细压力的变化;另外,为研究表面活性剂冲洗土壤中PCBs的去除机理,并降低PCBs对研究人员的危害,采用微观孔隙结构网络模型是一种较新颖的和效果显著的研究方法.开展表面活性剂冲洗PCBs污染土壤多相流研究,可以为PCBs污染场地修复提供理论基础和实验支持,并促进我国POPs履约工作的顺利进行.

Advances in multiphase fluid study of surfactant flushing PCBs in soil

Polychlorinated biphenyls are a kind of persistent organic pollutants, which have some characteristics like persistent, anti biodegradability, fat solubility and biological toxicity. Because of difficult to locate accurately, difficult to be decomposed and strong adsorption, PCBs are removed difficultly from soil. Surfactant flushing can remove PCBs from soil by improving the solubility of PCBs and decreasing interfacial tension between water and PCBs. Surfactant flushing PCBs from soil are relate with gas phase, water phase, NAPLs phase and solid phase, which is a progress of multiphase coexistence and interaction, and which cause the changes of relative permeability, saturation and capillary pressure. Moreover, to study the removing mechanism of surfactant flushing PCBs from soil and reduce PCBs harms to researchers, micro-pore network model is a new and remarkable research method. Multiphase fluid study of surfactant flushing PCBs in soil can provide theoretical basis and experimental support for PCBs remediation on contaminated sites, and can facilitate the future implementation of the Stockholm Convention on Implementing International Action on Certain Persistent Organic Pollutants.