生石灰强化机械通风法修复三氯乙烯污染土壤  

Quicklime-enhanced remediation of trichloroethylene contaminated soils by mechanical soil aeration

作　　者：马妍[1,2] 李发生[2] 徐竹[2] 史怡[3] 李慧颖[4] 李政[2] 黄绚[5] 杜晓明[2] 

机构地区：[1]北京师范大学地下水污染控制与修复教育部工程研究中心,北京100875 [2]中国环境科学研究院环境基准与风险评估国家重点实验室,北京100012 [3]北京科技大学土木与环境工程学院,北京100083 [4]北京市环境保护科学研究院污染场地风险模拟与修复北京市重点实验室,北京100037 [5]浙江省环境保护科学设计研究院,浙江杭州310007

出　　处：《环境污染与防治》2014年第9期1-6,共6页Environmental Pollution & Control

基　　金：2014年环保公益项目(No.201409047)

摘　　要：机械通风法是一种操作简单、效果好、成本低的土壤修复技术,特别适合大型挥发性有机化合物(VOC)污染场地的土壤修复,但在环境温度低、土壤含水率高、土壤黏性大等情况下,其修复效果和修复周期会受到极大影响,且土壤中高浓度的污染物残留将严重影响场地修复目标的实现。为了解决这一问题,采用了在土壤中添加一定量生石灰的强化措施。结果表明:(1)生石灰可以显著提高机械通风法修复三氯乙烯(TCE)污染土壤的效果,缩短修复周期,降低污染物在土壤中的残留浓度。(2)生石灰对TCE的强化作用与生石灰的添加量和土壤类型有关,粉质黏土的强化效果要好于粉土和细砂,生石灰添加量越多,强化效果越好;(3)生石灰强化处理TCE的主要机制是提高土壤温度、降低土壤含水率、增加土壤通透性,促进土壤中TCE的解吸和挥发。Mechanical soil aeration is an effective and low-cost ex-situ remediation technique which suitable for large areas of land contaminated with volatile organic compounds （VOC）.But under conditions of low temperature,high soil moisture content and high soil viscosity,it not only necessitates time-consuming remediation activity but also produces high contaminant residue in soil,elevating contaminant concentrations above the target values required for site remediation.To address this issue,a lab-scale study of contaminated soil remediation using quicklime （CaO） was conducted to investigate the enhanced effect on mechanical soil aeration process,the results demonstrate that：（1）adding CaO at remediation site could sufficiently reduce trichloroethylene （TCE） levels and significantly shorten the remediation time.（2） The enhanced removal of TCE varied with the amount of CaO dose and soil type,CaO-enhanced remediation of silty clay is better than that of silt soil and sandy soil; the more CaO added,the better enhanced effect would be.（3） The following major actions can enhance site remediation by CaO：increasing the soil temperature and permeability,decreasing soil moisture and finally promoting the desorption and evaporation of TCE in soil.

关 键 词：生石灰 机械通风技术 强化修复 三氯乙烯污染土壤 

分 类 号：X53[环境科学与工程—环境工程]