多环芳烃类污染场地应用原位电热脱附技术的能效分析

针对华东某多环芳烃类污染场地，通过应用原位电热脱附修复技术，系统分析了运行过程中加热温度、加热时间、气相抽提密度等关键参数的变化规律，并对修复效果、抽提气体浓度、能耗等运行参数进行分析。结果表明:原位电热脱附对多环芳烃类污染物具有良好的去除效果，加热运行250 d后，场地土壤温度均可达到300 ℃以上，污染物去除率达到99.99%以上，修复后土壤污染物浓度值低于修复目标值的要求。土壤加热温度、加热时间、气相抽提密度是影响原位电热脱附修复效果的关键因素，进而提出了降低修复成本的施工经验，为高温原位电热脱附的推广和工程化应用提供借鉴。

ENERGY EFFICIENCY ANALYSIS OF IN-SITU ELECTROTHERMAL DESORPTION TECHNOLOGY IN POLYCYCLIC AROMATIC HYDROCARBONS (PAHS) CONTAMINATED SITE

In this paper, the in-situ electrothermal desorption remediation technology was applied to a polycyclic aromatic hydrocarbon (PAHs) contaminated site in East China. The changes of key parameters such as heating temperature, heating time and gas phase extraction density during operation were systematically analyzed, and the operating parameters such as the remediation effect, extraction gas concentration and energy consumption were also analyzed. The results showed that the in situ electrothermal desorption had a good removal effect on PAHs. After 250 days of heating, the soil temperature of the site reached above 300 ℃, and the pollutant removal rate reached more than 99.99%. The concentration of soil pollutants after remediation was lower than the requirements of the target value of remediation. The heating temperature, heating time and gas phase extraction density of soil were the key factors affecting the effect of in-situ electrothermal desorption remediation, and the construction experience of reducing the cost of remediation was put forward, which could provide references for the promotion and engineering application of high-temperature in-situ electrothermal desorption.