PRB修复多组分与单组分污染地下水的实验

Studies on PRB Repairing Multi-Component and One Component of the Polluted Groundwater

目的为膨润土资源的开发利用和PRB的工程实践提供新的途径和可行的技术参数.方法以多组分垃圾渗滤液污染地下水和单组分苯酚污染地下水为研究对象,以改性膨润土—阴/阳离子有机膨润土(Na-ACOMMT)作为反应介质,进行了污染地下水修复研究.结果阴、阳离子表面活性剂已进入膨润土的层间结构中,使阴/阳离子有机膨润土(Na-ACOMMT)的层间距由0.949 nm(提纯膨润土)增大到1.988 nm;Na-ACOMMT对水中有机物产生协同去除效果,对Cr6+的吸附是物理吸附和化学吸附联合作用的结果,对NH4+的吸附主要是离子吸附和交换作用;在实验稳定阶段,Na-ACOMMT对多组分污染地下水中COD和Cr6+的去除率在50%左右,对NH4+的去除率在40%左右,对单组分苯酚污染地下水的去除率在70%左右.结论以Na-ACOMMT作为PRB的反应介质修复污染地下水是可行,且对单组分污染地下水的修复明显好于对多组分污染地下水的修复.

The purpose of this article is to provide the new way and feasible technical parameters for the development and utilization of Bentonite resources and the Permeable Reactive Barrier（ PRB ） engineering practice. The object of the study is the polluted groundwater by the multi-component of trash percolating liquid or one-component of phenol. The reaction medium is the Anion-cation organic bentonite in-situ remediation study on the polluted groundwater. The experiment results show that the cationic-anionic surfactants have entered into interlayer structure of bentonite and increased the interlayer distance from 0.949 nm of the purified bentonite to 1. 988 nm of the Anion-cation organic bentonite. The synergistic effect of ion exchange and adsorption in removing organic substance has been demonstrated. The adsorption of Cr^6＋ is the mutual effect result of physical adsorption and chemical absorption. The adsorption of ammonium is the ion adsorption and exchange. In the experiment stable stage, the removal rates of COD and Cr^6＋ of the multi-component, ammonium and phenol of the one-component are 50% ,40% and 50% respectively. It is feasible that Anion-cation organic bentonite as the reaction medium of PRB is used to remedy the polluted groundwater. At the same time, the effect of remediation of the polluted groundwater by one-component is better than that by the multicomponents.