地下水循环井技术处理土壤和地下水中甲基叔丁基醚研究

研究了MTBE在砂土中的静态吸附以及采用地下水循环井技术(GCW)去除砂土和地下水中MTBE的衰减规律。结果表明:MTBE在砂土中的吸附动力学符合准二级动力学方程,相关系数R2为0.99618,在砂土中的吸附平衡时间为24 h;吸附热力学符合Linear平衡吸附,吸附系数为0.00306 m3/kg。GCW运行30 h后,地下水饱和含水层中MTBE浓度由500 mg/L降至72.5 mg/L,去除率为85.5%;砂土中MTBE的吸附量由0.93 mg/g降至0.03 mg/g,去除率达96.4%。水平方向距GCW越近,MTBE的去除效率越快,垂直方向位于GCW上部的MTBE优先会被去除,最佳修复时间为运行15 h。GCW对砂土和地下水中高浓度MTBE具有良好的修复效果。

STUDY ON MTBE REMEDIATED IN SOIL AND GROUNDWATER BY GCW

In this paper,the static adsorption of MTBE in sand,as well as the removal of MTBE in sand and groundwater by groundwater circulation well (GCW) was claimed.The results showed that the adsorption kinetics model followed second-order kinetics,with the correlation coefficient (R2) of 0.99618,and the time for adsorption equilibrium was 24 h.The adsorption thermodynamics followed the linear adsorption,and the adsorption coefficient was 0.00306 m3/kg.After 30 h of reaction,the MTBE concentration in groundwater declined from 500 mg/L to 72.5 mg/L and the removal rate reached 85.5％.At the same time,the adsorption capacity of MTBE in sand decreased from 0.93 mg/g to 0.03 mg/g,and the removal rate was 96.4％.The removal efficiency would be better if the MTBE was closer to the GCW in groundwater horizontal direction,meanwhile,the MTBE located vertically above the GCW was preferentially removed.This study also showed that the best remediation time was 15 h.Therefore,it could be claimed that the GCW had a good repair effect on high concentration of MTBE in sand and ground water.