title: Low-concentration tailing and subsequent quicklime-enhanced remediation of volatile chlorinated hydrocarbon-contaminated soils by mechanical soil aeration.
abstract: Mechanical soil aeration has long been regarded as an effective ex-situ remediation technique and as suitable for remediation of large-scale sites contaminated by volatile organic compounds (VOCs) at low cost. However, it has been reported that the removal efficiency of VOCs from soil is relatively low in the late stages of remediation, in association with tailing. Tailing may extend the remediation time required; moreover, it typically results in the presence of contaminants residues at levels far exceeding regulations. In this context, the present study aimed to discuss the tailing that occurs during the process of remediation of soils contaminated artificially with volatile chlorinated hydrocarbons (VCHs) and to assess possible quicklime-enhanced removal mechanisms. The results revealed the following conclusions. First, temperature and aeration rate can be important controls on both the timing of appearance of tailing and the levels of residual contaminants. Furthermore, the addition of quicklime to soil during tailing can reduce the residual concentrations rapidly to below the remedial target values required for site remediation. Finally, mechanical soil aeration can be enhanced using quicklime, which can improve the volatilization of VCHs via increasing soil temperature, reducing soil moisture, and enhancing soil permeability. Our findings give a basic understanding to the elimination of the tailing in the application of mechanical soil aeration, particularly for VOCs-contaminated soils.
authors.affiliation: College of Water Sciences, Beijing Normal University, Beijing 100875, China; State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Ma
authors.affiliation: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Du
authors.affiliation: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Beijing University of Science and Technology, Civil and Environment Engineering Department, Beijing 100083, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Shi
authors.affiliation: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
authors.forename: Zhu
authors.initials: Z
authors.lastname: Xu
authors.affiliation: Shandong Key Laboratory of Eco-Environmental Science for Yellow River Delta, Binzhou University, Binzhou, Shandong Province 256600, China.
authors.forename: Jidun
authors.initials: J
authors.lastname: Fang
authors.affiliation: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Li
authors.affiliation: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China. Electronic address: ligulax@vip.sina.com.
authors.forename: Fasheng
authors.initials: F
authors.lastname: Li
mesh_terms: D017610:Calcium Compounds / Q000737:chemistry*; D052918:Environmental Restoration and Remediation; D006843:Hydrocarbons, Chlorinated / Q000032:analysis*; D010087:Oxides / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry*; D012987:Soil / Q000737:chemistry* / Q000592:standards; D012989:Soil Pollutants / Q000032:analysis*; D013696:Temperature; D055549:Volatile Organic Compounds / Q000032:analysis*; D014835:Volatilization
chemical_list: D017610:Calcium Compounds; D006843:Hydrocarbons, Chlorinated; D010087:Oxides; D012987:Soil; D012989:Soil Pollutants; D055549:Volatile Organic Compounds; C016538:lime; D010100:Oxygen
keywords: Enhanced remediation; Low-concentration tailing; Mechanical soil aeration; Quicklime; Volatile chlorinated hydrocarbon-contaminated soils