降雨对土壤中甲苯运移影响的初步研究

Preliminary Research of the Effect of Rainfall on Toluene Migration in Soil

甲苯是最为常见的挥发性有机污染物之一,针对土壤与地下水挥发性有机污染问题日益严重的现状,本文以甲苯为研究对象,采用原位土柱物理模拟试验,通过降雨与土壤参数监测以及土壤和土壤气体取样分析,研究了降雨条件下土壤中甲苯多相运移规律;基于降雨引起的土壤水分动态分布与污染物分布特征的对比分析,初步探讨了降雨对其运移过程的影响.研究发现,甲苯在土壤中的运移受其自身的挥发性影响较大,且存在与水分运移不同步的现象,其固相运移速率小于气相扩散速率和土壤水分运移速度;降雨加快了其运移速度,对甲苯的运移有促进作用.

Taking into account the increasingly serious soil and groundwater pollution by volatile organic compounds ,toluene ,a major volatile organic compound ,was selected as the research object in this study . With the methods of in situ soil column physical simulation experiments ,monitoring rainfall and soil pa-rameters and sampling and analysing soil and soil gases ,multi-phase migration of toluene in the soil was studied .The dynamic distributions of soil water and pollutants were compared to investigate the effect of rainfall on the migration of volatile organic compounds .The results showed that migration of toluene in the soil was mainly influenced by its own volatility and asynchronous with that of soil moisture ,that the mi-gration rate of solid-phase toluene was smaller than that of gas-phase toluene and soil moisture ,and that rainfall accelerated the migration of toluene .