摘要
采用热脱附技术处理实际石油烃污染土壤,考察影响热脱附效率的影响因素,并结合工程实际,初步确定热脱附技术的最优工艺参数。实验结果表明,热脱附技术可有效修复石油烃污染土壤,其中加热温度、停留时间是影响修复效果的关键因素。相同热脱附条件下,石油烃组分相对分子质量越大,饱和蒸气压越低,与土壤有机质结合能力越强,越不易脱附。当加热温度为150℃时,随着停留时间的延长,不同石油烃组分的热脱附效率各有增减,总体变化不大。停留时间为10 min,加热温度为150~300℃时,各石油烃组分的热脱附效率随加热温度的升高而增大。加热温度达到300℃及以上时,土壤中各石油烃组分的含量均低于检出限。通过正交实验设计筛选热脱附技术工程应用的最佳运行参数为加热温度250℃、停留时间15 min,土壤热脱附处理后总石油烃为513 mg/kg,可满足建设用地土壤环境质量要求。
Thermal desorption technology was applied to treat actual petroleum hydrocarbon-contaminated soil,the influencing factors of thermal desorption efficiency were investigated,and the optimal technological parameters of thermal desorption technology were preliminarily determined based on engineering practice.The experimental results revealed that thermal desorption technology could effectively remediate petroleum hydrocarbon-contaminated soil,and heating temperature and residence time were the key factors affecting the remediation efficiency.Under the same thermal desorption conditions,the petroleum hydrocarbons with higher relative molecular weight would be more difficult to volatilize due to the lower saturated vapor pressure and the stronger binding ability with soil organic matter.When the heating temperature was 150℃,the thermal removal efficiency of different petroleum hydrocarbons fluctuated with the increase of residence time.When the residence time was 10 min and the heating temperature was 150-300℃,the thermal desorption efficiency increased with the increase of heating temperature.When the heating temperature reached 300℃or above,the petroleum hydrocarbons in soil were all below the detection limit.Through orthogonal experimental design,the optimal operation parameters of thermal desorption technology for engineering application were obtained as heating temperature of 250℃and residence time of 15 min.The total petroleum hydrocarbon content in soil was 513 mg/kg after thermal desorption treatment,which could meet the requirements of soil environmental quality for construction land.
作者
张坤
张杰西
王钪
籍龙杰
王亚晨
刘鹏
李静文
李书鹏
马福俊
ZHANG Kun;ZHANG Jiexi;WANG Kang;JI Longjie;WANG Yachen;LIU Peng;LI Jingwen;LI Shupeng;MA Fujun(Beijing Construction Engineering Group Environmental Remediation Co.,Ltd.,Beijing 100015;National Engineering Laboratory for Site Remediation Technologies,Beijing 100015;Beijing Construction Engineering Group Green Energy Environmental Technology Co.,Ltd.,Beijing 100015;State Key Laboratory of Environmental Criteria and Risk Assessment,Chinese Research Academy of Environmental Sciences,Beijing 100012)
出处
《环境污染与防治》
CAS
CSCD
北大核心
2022年第3期297-301,共5页
Environmental Pollution & Control
基金
国家重点研发计划项目(No.2018YFC1802100)
中国博士后科学基金面上项目(No.2019M660823)。
关键词
热脱附
石油烃
热脱附效率
土壤修复
thermal desorption
petroleum hydrocarbon
thermal desorption efficiency
soil remediation
