气相抽提法去除土壤中的苯和乙苯

Removal of benzene and ethylbenzene from soil by soil vapor extraction

土壤气相抽提技术(SVE)是一种安全、经济、高效的土壤治理技术,广泛应用于不饱和土壤中挥发性有机污染物的去除。以红壤为实验土样,北京潮土和吉林黑土为对照土样,选用最常见的挥发性有机污染物苯作为单一污染物,采用一维土柱通风模拟SVE过程,研究了不同土质对苯污染土壤去污过程的影响。同时选用苯与乙苯作为二元混合污染物,研究了土壤含水率对苯与乙苯污染红壤去污过程的影响。结果表明,对于二元混合物实验,在通风流量600 ml.min-1、含水率16.8%时,苯与乙苯的净化时间分别降至最低36 h和84 h。不同类型土壤的对照实验表明,土壤质地与有机质含量也是SVE去污过程的重要影响因素。

Soil vapor extraction （SVE） has been effectively used for removal of volatile organic compounds （VOCs） from unsaturated soil. It is safe, economical and highly efficient. Column-venting experiment was used to simulate the SVE in the typical red earth in south China. Benzene, one of the most common VOCs, was selected as the single compound. Fluvo-aquic soil of Beijing and black soil of Jilin were selected as the control samples to study the effect of soil types on the SVE remediation process. Different soil water content on the venting behavior of a binary mixture （benzene and ethylbenzene） from the red earth was also investigated. The results showed that the best soil water content was 16.8 % at the 600 ml · min^-1 vapor flow rate for the binary mixture. Control experiments indicated that soil type and soil organic matter were also key factors in SVE.