柴油污染包气带环境的自然衰减作用

Research on the natural attenuation of vadose zone polluted by diesel

为定量研究柴油污染包气带环境的自然衰减过程中吸附、生物和挥发作用,通过吸附实验确定细砂和亚黏土对柴油饱和溶液的吸附平衡时间均为24 h,对总石油烃的理论最大吸附量分别为234和430 mg.kg-1.经6个模拟柱的淋滤对比实验,建立总石油烃生物降解作用和挥发作用的一级衰减动力学方程:在细砂中分别为ρ(TPH)=25.48e-0.0027x和ρ(TPH)=25.48e-0.0221x,在亚黏土中分别为ρ(TPH)=25.48e-0.0051x和ρ(TPH)=25.48e-0.010 9x.结果表明,在柴油污染包气带环境中,总石油烃在亚黏土中的自然衰减效率高于细砂.

To quantitatively study the adsorption,biodegradation and volatilization of diesel polluted vadose zone environment during natural attenuation process,adsorption experiments were conducted to determine the adsorption equilibrium time of fine sand and clay vs saturated solution of diesel,which were 24 h,and the theoretical maximum adsorption capacity of the total petroleum hydrocarbons（TPH） of fine sand and clay were 234 and 430 mg·kg-1 respectively.The comparative experiments including six columns established the biodegradation and volatilization decay kinetic equations of fine sand polluted by diesel,ρ（TPH）=25.48e-0.002 7xand ρ（TPH）=25.48e-0.022 1x,and the equations of clay,ρ（TPH）=25.48e-0.005 1xand ρ（TPH）=25.48e-0.010 9x.The results showed that natural attenuation efficiency of clay polluted by diesel was greater than that of fine sand.