地下水石油污染的原位空气曝气修复技术

针对东北某石油污染场地水文地质条件进行模拟,按照试验场地地层现状进行实验室缩放。选取苯和二甲苯作为目标石油污染物,采用电阻层析成像技术测定空气曝气技术的影响半径,研究非均质介质砾砂、粗砂和中砂条件下,空气曝气技术对苯和二甲苯的去除效果。实验结果表明:在非均匀介质中的影响半径不是围绕曝气井呈中心对称分布的,存在气体偏流和绕流现象。空气曝气技术(AS)对中砂层中苯和二甲苯的去除效果要比砾砂层和粗砂层的好;曝气15 d后,AS对苯和二甲苯的去除率分别为75.6%和71.3%。AS在去除污染物的过程中,存在明显的拖尾现象。

In-situ air sparging remediation of petroleum contaminated groundwater

Based on the hydro-geological conditions of petroleum contaminated sites in Northeast of China,the lab scale experiments were set up.Benzene and xylene were selected as target petroleum pollutants.The radius of influence was investigated by using electrical resistance tomography,the removal efficiency of benzene and xylene was studied by using air sparging(AS) technique in heterogeneous soil.The results show that the gas distribution is not presented axisymmetric around aeration well,existing bios flow and flow around.The removal efficiency in medium sand is better than that in coarse sand and gravel sand.After 15 d running,the removal efficiencies of benzene and xylene by AS technique reached to 75.6% and 71.3%,respectively,and there has an obvious tailing phenomenon in the process.