热传导强化气相抽提处理苯系物污染土壤实验

Thermodesorption of BTEX-contaminated soil using heat conduction

以苯系物(BTEX)污染土壤为研究对象,研究加热源功率和加热时间对土壤苯系物去除率的影响;实验通过分析尾气和冷凝水的污染物浓度来判断实验的终止时间点.结果显示,在3个功率100、200 W和400 W作用下,各污染物的残留浓度较低,所需要的处理时间分别为168.5、122.5 h以及104 h,消耗的总电能分别为:0.49、0.56 KW.h.Kg-1TS以及0.81 kW.h.Kg-1TS.功率越高,土壤中BTEX去除效率越高,同时能耗也越大.实验通过分析处理前后土壤中有机质含量,发现在加热的条件下有机质会逐渐减少,功率越高,有机质去除的速率越快,越有利于污染物的去除.本文的结果可证实通过加热可有效提高土壤中苯系物的气相抽提去除效率,对现场中试的开展提供参数依据.

In this paper, thermodesorption of BTEX-contaminated soil using heat conduction was investigated. Essential processing parameters such as heating power and heating time were examined. The concentrations of the exhaust gas and condensate were analyzed to determine the termination point of the experiment. The results reveal that using three distinct heating powers, the removal rate for all BTEX contaminants were considerady low. More importantly, the treatment duration and the total energy consuption for 100 W, 200 W and 400 W were 168.5 h, 122.5 h, 104 h and O. 49,0.56,0.81 kW. h-1. kg-I TS, indicating that the highest energy power input consumed the highest energy. The change in soil organic matter concentration after the treatment was investigated. It was shown that the organic matter concentration gradually reduced under the heating condition, and the rate of the organic matter removal was conducive to degradation of the contaminants. The results in BTEX can be enhanced by using heating conduction. directly proportional to the power, and more this study confirmed that thermal desorption of