氯代烃污染场地原位热脱附降温阶段土壤气相污染富集与分布特征

李慧颖; 王盼盼; 刘鹏; 李发生; 曹云者

doi:10.13198/j.issn.1001-6929.2022.03.19

氯代烃污染场地原位热脱附降温阶段土壤气相污染富集与分布特征

doi: 10.13198/j.issn.1001-6929.2022.03.19

1.
生态环境部土壤与农业农村生态环境监管技术中心，北京　100012
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.
北京建工环境修复股份有限公司，北京　100015

基金项目: 国家重点研发计划项目(No.2018YFC1801400, 2018YFC1801404)

详细信息

作者简介:
李慧颖（1982-），女，河北唐山人，副研究员，博士，主要从事多孔介质中污染物迁移研究，lihuiying@tcare-mee.cn

通讯作者:
曹云者(1972-)，女，河北辛集人，研究员，博士，主要从事土壤修复研究，caoyunzhe@tcare-mee.cn

中图分类号: X143
计量
- 文章访问数: 501
- HTML全文浏览量: 285
- PDF下载量: 90
- 被引次数: 0
出版历程
- 收稿日期: 2021-10-31
- 修回日期: 2022-03-15

Enrichment and Distribution Characteristics of Soil Gas-Phase Contamination in Cooling Stage of In-situ Thermal Desorption at Chlorinated Hydrocarbon Contaminated Site

1.
Technical Centre for Soil, Agricultural and Rural Ecology and Environment, Ministry of Ecology and Environment, Beijing 100012, China
2.
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
3.
Beijing Construction Engineering Environmental Remediation Co., Ltd., Beijing 100015, China

Funds: National Key Research and Development Program of China (No.2018YFC1801400, 2018YFC1801404)

摘要

摘要: 原位热脱附是近年来我国兴起和大规模应用的修复技术，为明确修复中不同介质污染物浓度水平，解决原位热脱附修复后全面效果评估问题，以某氯代烃污染场地原位热脱附修复工程为案例，采集修复加热周期结束进入降温阶段时土壤和土壤气体剖面样品进行检测分析，识别修复后期土壤和土壤气中目标污染物的浓度水平、空间分布特征以及影响因素，并提出对于原位热解吸修复后土壤修复效果评估和二次污染防控建议. 结果表明：①案例场地土壤中氯代挥发性有机污染物仅1%痕量检出，所有样品均达到修复目标值. ②土壤气中污染物有不同浓度检出，其中三氯乙烯最大浓度为2 310 μg/m³，有潜在健康风险. ③低渗透层对气相污染物迁移具有阻滞作用，地表的水泥层下积聚了不同浓度的污染物. ④三氯乙烯、四氯乙烯和顺式-1,2-二氯乙烯的沸点低，土壤有机碳分配系数(K_OC)低，垂向迁移效率高，它们在土壤气中的浓度最大值均出现在顶层；六氯丁二烯相对沸点高，K_OC高，其浓度最大值出现在深层粉质黏土低渗透地层处. 研究显示，原位热脱附技术对于土壤中高浓度氯代烃污染具有较好的去除效果，但是研究时段内土壤达到修复标准后土壤气中污染物仍有不同程度检出. 因此，建议原位热脱附修复后，应同时对土壤和土壤气两种介质进行采样评估，同时加强原位热脱附区域低渗透层识别，优化气相抽提方案.
- 氯代烃 /
- 原位热脱附 /
- 土壤气 /
- 多介质污染监测与评估
Abstract: In-situ thermal desorption (ISTD) is a remediation technology that has emerged and been applied on a large scale in China in recent years. In order to clarify the concentration levels of pollutants in different media during remediation and to carry out verification scientifically after remediation, the ISTD remediation project of a chlorinated hydrocarbon contaminated site was used as a case study. At the end of the remediation heating cycle into the cooling stage, soil and soil gas profile samples were collected for testing and analysis to finely identify the concentration levels and spatial distribution characteristics of pollutants in soil and soil gas. The effects of pollutant physicochemical properties, stratigraphic structure, especially the low permeability layer on gas migration and pollution distribution were analyzed. In view of this, the verification of soil remediation and the secondary pollution prevention and control after ISTD were proposed. The results showed that: (1) Only 1% of soil samples were detected of chlorinated volatile organic pollutants in trace amounts in this case, and all samples met the remediation target values. (2) Pollutants in soil gas were detected at different concentrations, among which trichloroethylene was detected at the highest concentration of 2310 μg/m³, which has a potential health risk. (3) The low permeable layer has a blocking effect on the migration of gas-phase pollutants, and high concentrations of pollutants accumulated under the surface cement layer. (4) Trichloroethylene, tetrachloroethylene and cis-1,2-dichloroethylene have low boiling points, low soil organic carbon partition coefficients (K_OC), high vertical migration efficiency, and the highest gas-phase pollutant concentrations in the top layer. Hexachlorobutadiene has a high relative boiling point and high K_OC, and the maximum value occurs in the deep low-permeability stratum. The study showed that the ISTD technology has a good removal effect for high concentration of chlorinated hydrocarbon pollution, but the contaminants were still detected in soil gas after the soil reached the standard in this case study. Therefore, it is recommended that both multi-media verification of soil and soil gas should be conducted after ISTD remediation for a comprehensive assessment. The identification of low permeability layers in the ISTD area should be enhanced to optimize the gas phase extraction scheme.
- chlorinated hydrocarbons /
- in-situ thermal desorption /
- soil gas /
- multi-media pollution monitoring and assessment

HTML全文

图 1 原位热脱附修复工程及样品采集示意

Figure 1. Schematic diagram of ISTD project and sample collection

下载: 全尺寸图片幻灯片

图 2 修复降温1个月后土壤三氯乙烯和四氯乙烯浓度的垂向分布

注：S-1、S-2、S-3、S-4分别为修复降温阶段土壤剖面采样点.

Figure 2. Vertical distribution characteristics of pollutant concentrations in soil in the cooling stage of ISTD

下载: 全尺寸图片幻灯片

图 3 修复降温1个月后土壤气污染物浓度的垂向分布

Figure 3. Vertical distribution characteristics of pollutant concentrations in soil gas in the cooling stage of ISTD

下载: 全尺寸图片幻灯片

表 1 研究区域主要关注污染物的理化性质

Table 1. Physical and chemical properties of pollutants of concern in the site

污染物	化学物质登记号	挥发特性			分配性质		密度/ (g/cm³)	溶解度/ (mg/L)
污染物	化学物质登记号	亨利系数	沸点^[30]/℃	25 ℃饱和蒸气压^[31]/(mmHg)	K_OC/(L/kg)	lg K_OW	密度/ (g/cm³)	溶解度/ (mg/L)
三氯乙烯	79-01-6	0.40	87.1	69.00	60.70	2.42	1.46	1 280.00
四氯乙烯	127-18-4	0.72	121.3	18.50	94.94	3.40	1.62	206.00
顺式-1,2-二氯乙烯	156-59-2	0.17	60.0	200.00	39.60	1.86	1.28	6 410.00
六氯丁二烯	87-68-3	0.42	215.0	0.22	845.20	4.78	1.56	3.20

下载: 导出CSV

表 2 土壤气中污染物浓度最大值与典型区域土壤气筛选值比较

Table 2. Maxum concentration of soil gas compared to different screening levels

污染物	土壤气中污染物浓度最大值/(μg/m³)	土壤气筛选值/(μg/m³)
污染物	土壤气中污染物浓度最大值/(μg/m³)	北京市^[35]	曼彻斯特^[36]	马里兰^[37]	密歇根^[38]	阿拉斯加^[39]
三氯乙烯	2 310	1 177	28	42	100	20
四氯乙烯	265	—	98	840	1 300	410
顺式-1,2-二氯乙烯	821	—	56	740	1 800	—
六氯丁二烯	669	—	7.4	22.6	62	13

下载: 导出CSV

参考文献(48)

[1]	HERON G,BAKER R S,LACHANCE J,et al.Thermal conduction heating for DNAPL removal in low-permeability soils and bedrock[C].Milan,Italy:10th International UFZ-Deltares/TNO Conference on Soil-Water Systems,2008.
[2]	United States Environmental Protection Agency.Superfund remedy report[R].16th edition.Washington DC:Office of Land and Emergency Management,2020.
[3]	王锦淮.原位热脱附技术在某有机污染场地修复中试应用[J].化学世界,2018,59(3):182-186. WANG J H.Application of in situ thermal desorption technology for remediation of an organic contaminated site[J].Chemical World,2018,59(3):182-186.
[4]	孟宪荣,葛松,许伟,等.原位电阻热脱附修复氯代烃污染土壤[J].环境工程学报,2021,15(2):669-676. doi: 10.12030/j.cjee.202009077 MENG X R,GE S,XU W,et al.Remediation of chlorohydrocarbon contaminated soil by in situ electrical resistance heating[J].Chinese Journal of Environmental Engineering,2021,15(2):669-676. doi: 10.12030/j.cjee.202009077
[5]	张学良,李群,周艳,等.某退役溶剂厂有机物污染场地燃气热脱附原位修复效果试验[J].环境科学学报,2018,38(7):2868-2875. ZHANG X L,LI Q,ZHOU Y,et al.In-situ remediation of organics-contaminanted site by gas thermal desorption at a retired solvent plant[J].Acta Scientiae Circumstantiae,2018,38(7):2868-2875.
[6]	刘惠.污染土壤热脱附技术的应用与发展趋势[J].环境与可持续发展,2019,44(4):144-148. LIU H.Application and development trend of thermal desorption technology for contaminated soil[J].Environment and Sustainable Development,2019,44(4):144-148.
[7]	MCGUIRE T M,MCDADE J M,NEWELL C J.Performance of DNAPL source depletion technologies at 59 chlorinated solvent-impacted sites[J].Groundwater Monitoring & Remediation,2006,26(1):73-84.
[8]	康绍果,李书鹏,范云.污染地块原位加热处理技术研究现状与发展趋势[J].化工进展,2017,36(7):2621-2631. KANG S G,LI S P,FAN Y.Research status and development trend of in situ thermal treatment technologies for contaminated site[J].Chemical Industry and Engineering Progress,2017,36(7):2621-2631.
[9]	王瑛,李扬,黄启飞,等.污染物浓度与土壤粒径对热脱附修复DDTs污染土壤的影响[J].环境科学研究,2011,24(9):1016-1022. WANG Y,LI Y,HUANG Q F,et al.Effects of different pollutant concentrations and soil particle size on thermal desorption efficiency of DDT-contaminated soil[J].Research of Environmental Sciences,2011,24(9):1016-1022.
[10]	CHOWDHURY A I A,GERHARD J I,REYNOLDS D,et al.Low permeability zone remediation via oxidant delivered by electrokinetics and activated by electrical resistance heating:proof of concept[J].Environmental Science & Technology,2017,51(22):13295-13303.
[11]	HERON G,LACHANCE J,BAKER R.Removal of PCE DNAPL from tight clays using in situ thermal desorption[J].Groundwater Monitoring & Remediation,2013,33(4):31-43.
[12]	缪周伟,吕树光,邱兆富,等.原位热处理技术修复重质非水相液体污染场地研究进展[J].环境污染与防治,2012,34(8):63-68. doi: 10.3969/j.issn.1001-3865.2012.08.014 MIAO Z W,LV S G,QIU Z F,et al.Progress of in situ thermal treatment technologies for DNAPLs contaminated site remediation[J].Environmental Pollution & Control,2012,34(8):63-68. doi: 10.3969/j.issn.1001-3865.2012.08.014
[13]	任加国,郜普闯,徐祥健,等.地下水氯代烃污染修复技术研究进展[J].环境科学研究,2021,34(7):1641-1653. REN J G,GAO P C,XU X J,et al.Advances in remediation technology for chlorinated hydrocarbons contamination in groundwater[J].Research of Environmental Sciences,2021,34(7):1641-1653.
[14]	MERCER J W,COHEN R M.A review of immiscible fluids in the subsurface:properties,models,characterization and remediation[J].Journal of Contaminant Hydrology,1990,6(2):107-163. doi: 10.1016/0169-7722(90)90043-G
[15]	YOON H,WERTH C J,BARKAN C P L,et al.An environmental screening model to assess the consequences to soil and groundwater from railroad-tank-car spills of light non-aqueous phase liquids[J].Journal of Hazardous Materials,2009,165(1/2/3):332-344.
[16]	LENHARD R J,OOSTROM M,DANE J H.A constitutive model for air-NAPL-water flow in the vadose zone accounting for immobile,non-occluded (residual) NAPL in strongly water-wet porous media[J].Journal of Contaminant Hydrology,2004,71(1/2/3/4):261-282.
[17]	刘玉兰,程莉蓉,丁爱中,等.NAPL泄漏事故场地地下水污染风险快速评估与决策[J].中国环境科学,2011,31(7):1219-1224. LIU Y L,CHENG L R,DING A Z,et al.Quick assessment of groundwater risk after NAPL spill and its application in site emergency management[J].China Environmental Science,2011,31(7):1219-1224.
[18]	CONRAD S H,WILSON J L,MASON W R,et al.Visualization of residual organic liquid trapped in aquifers[J].Water Resources Research,1992,28(2):467-478. doi: 10.1029/91WR02054
[19]	YOON H,VALOCCHI A J,WERTH C J.Effect of soil moisture dynamics on dense nonaqueous phase liquid (DNAPL) spill zone architecture in heterogeneous porous media[J].Journal of Contaminant Hydrology,2007,90(3/4):159-183.
[20]	COSTANZA M S,BRUSSEAU M L.Contaminant vapor adsorption at the gas-water interface in soils[J].Environmental Science & Technology,2000,34(1):1-11.
[21]	KROL M M,SLEEP B E,JOHNSON R L.Impact of low-temperature electrical resistance heating on subsurface flow and transport[J].Water Resources Research,2011,47(5):W05546.
[22]	HERON G,VAN-ZUTPHEN M,CHRISTENSEN T H,et al.Soil heating for enhanced remediation of chlorinated solvents:a laboratory study on resistive heating and vapor extraction in a silty,low-permeable soil contaminated with trichloroethylene[J].Environmental Science & Technology,1998,32(10):1474-1481.
[23]	可欣,周燕,张飞杰,等.污染场地修复药剂安全利用问题及对策[J].环境科学研究,2021,34(6):1473-1481. KE X,ZHOU Y,ZHANG F J,et al.Problems and strategies of safe utilization of agents for contaminated sites[J].Research of Environmental Sciences,2021,34(6):1473-1481.
[24]	姜林,梁竞,钟茂生,等.复杂污染场地的风险管理挑战及应对[J].环境科学研究,2021,34(2):458-467. JIANG L,LIANG J,ZHONG M S,et al.Challenges and response to risk management of complex contaminated sites[J].Research of Environmental Sciences,2021,34(2):458-467.
[25]	宋易南,侯德义,赵勇胜,等.京津冀化工场地地下水污染修复治理对策研究[J].环境科学研究,2020,33(6):1345-1356. SONG Y N,HOU D Y,ZHAO Y S,et al.Remediation strategies for contaminated groundwater at chemical industrial sites in the Beijing-Tianjin-Hebei region[J].Research of Environmental Sciences,2020,33(6):1345-1356.
[26]	MUNHOLLAND J L,MUMFORD K G,KUEPER B H.Factors affecting gas migration and contaminant redistribution in heterogeneous porous media subject to electrical resistance heating[J].Journal of Contaminant Hydrology,2016,184:14-24. doi: 10.1016/j.jconhyd.2015.10.011
[27]	NGUYEN V T,ZHAO L,ZYTNER R G.Three-dimensional numerical model for soil vapor extraction[J].Journal of Contaminant Hydrology,2013,147:82-95. doi: 10.1016/j.jconhyd.2013.02.008
[28]	蒋村,孟宪荣,施维林,等.氯苯污染土壤低温原位热脱附修复[J].环境工程学报,2019,13(7):1720-1726. doi: 10.12030/j.cjee.201810082 JIANG C,MENG X R,SHI W L,et al.In-situ low temperature thermal desorption for remediation of the chlorobenzene contaminated soil[J].Chinese Journal of Environmental Engineering,2019,13(7):1720-1726. doi: 10.12030/j.cjee.201810082
[29]	迟克宇,李传维,籍龙杰,等.原位电热脱附技术在某有机污染场地修复中的应用效果[J].环境工程学报,2019,13(9):2049-2059. doi: 10.12030/j.cjee.201905110 CHI K Y,LI C W,JI L J,et al.Application effect of in situ electric thermal desorption technology used in remediation at an organics-contaminated site[J].Chinese Journal of Environmental Engineering,2019,13(9):2049-2059. doi: 10.12030/j.cjee.201905110
[30]	United States Environmental Protection Agency.EPA 712-C-96-034 product properties test guidelines OPPTS 830.7220 boiling point/boiling range[S].Washington DC:the U.S. Government Printing Office,1996.
[31]	United States Environmental Protection Agency.Regional Screening Levels (RSLs)-Generic Tables[S].Washington DC:US EPA,2022.
[32]	环境保护部.土壤和沉积物挥发性有机物的测定吹扫捕集/气相色谱-质谱法:HJ 605—2011[S].北京:中国环境科学出版社,2011.
[33]	环境保护部.环境空气挥发性有机物的测定罐采样/气相色谱-质谱法:HJ 759—2015[S].北京:中国环境科学出版社,2015.
[34]	HERON G,BIERSCHENK J,SWIFT R,et al.Thermal DNAPL source zone treatment impact on a CVOC plume[J].Groundwater Monitoring & Remediation,2016,36(1):26-37.
[35]	北京市质量技术监督局.污染场地挥发性有机物调查与风险评估技术导则:DB 11/T 1278—2015[S].北京:北京市质量技术监督局,2016.
[36]	Department of Environmental Protection,Common Wealth of Massachusetts,Executive Office of Energy & Environmental Affairs.WSC-16-435 vapor intrusion guidance:site assessment,mitigation and closure[S].Massachusetts:Commonwealth of Massachusetts Executive Office of Energy & Environmental Affairs Department of Environmental Protection,2016.
[37]	Maryland Department of the Environment.Technical Guidelines for Vapor intrusion[S].Maryland,USA:Maryland Department of the Environment,2019.
[38]	Michigan Department of Environmental Quality.Guidance document for the vapor intrusion pathway[S].State of Michigan:Department of Environmental Quality,2012.
[39]	Department of Environmental Conservation,State of Alaska.Vapor intrusion guidance for contaminated sites[S].Alaska:Department of Environmental Conservation,2017.
[40]	MARTIN E J,KUEPER B H.Observation of trapped gas during electrical resistance heating of trichloroethylene under passive venting conditions[J].Journal of Contaminant Hydrology,2011,126(3/4):291-300.
[41]	MARTIN E J,MUMFORD K G,KUEPER B H.Electrical resistance heating of clay layers in water-saturated sand[J].Groundwater Monitoring & Remediation,2016,36(1):54-61.
[42]	ALBERGARIA J T,ALVIM-FERRAZ M C M,DELERUE-MATOS C.Soil vapor extraction in sandy soils:influence of airflow rate[J].Chemosphere,2008,73(9):1557-1561. doi: 10.1016/j.chemosphere.2008.07.080
[43]	YU Y,LIU L,YANG C Y,et al.Removal kinetics of petroleum hydrocarbons from low-permeable soil by sand mixing and thermal enhancement of soil vapor extraction[J].Chemosphere,2019,236:124319. doi: 10.1016/j.chemosphere.2019.07.050
[44]	YOON H,OOSTROM M,WIETSMA T W,et al.Numerical and experimental investigation of DNAPL removal mechanisms in a layered porous medium by means of soil vapor extraction[J].Journal of Contaminant Hydrology,2009,109(1/2/3/4):1-13.
[45]	XIE Q L,MUMFORD K G,KUEPER B H,et al.A numerical model for estimating the removal of volatile organic compounds in laboratory-scale treatability tests for thermal treatment of NAPL-impacted soils[J].Journal of Contaminant Hydrology,2019,226:103526. doi: 10.1016/j.jconhyd.2019.103526
[46]	赵勇胜,杨元元,高鹏龙,等.多孔介质中热蒸汽的迁移特性及其修复氯苯污染土壤的效果[J].吉林大学学报(地球科学版),2019,49(5):1431-1437. ZHAO Y S,YANG Y Y,GAO P L,et al.Migration characteristics of steam and its remediation to chlorobenzene contaminated soil[J].Journal of Jilin University (Earth Science Edition),2019,49(5):1431-1437.
[47]	戚圣琦,侯德义,王轶冬,等.VOCs相间非平衡态迁移对土壤修复效果的影响[J].环境科学研究,2021,34(6):1464-1472. QI S Q,HOU D Y,WANG Y D,et al.The influence of VOCs nonequilibrium transport on soil remediation[J].Research of Environmental Sciences,2021,34(6):1464-1472.
[48]	YANG M,ANNABLE M D,JAWITZ J W.Back diffusion from thin low permeability zones[J].Environmental Science & Technology,2015,49(1):415-422.