EGTA/TSP联合修复模拟重金属污染黄棕壤及其环境风险评价
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摘要
针对淋洗可能导致土壤残留重金属活化问题,研究淋洗/钝化联合修复对重金属污染土壤风险的削减作用。以乙二醇双(2-氨基乙基醚)四乙酸[ethylenebis (oxyethylenenitrilo) tetraacetic acid,EGTA]为淋洗剂,以重过磷酸钙(triple super phosphate,TSP)为钝化剂,研究了EGTA投加量、液固比、淋洗时间和TSP投加量等对模拟重金属污染黄棕壤中Cu、Zn、Pb和Cd 4种重金属洗脱率和浸出浓度的影响,通过响应面法设计多因素实验,拟合了土壤重金属环境风险削减率与EGTA投加量、液固比及TSP投加量之间的关系,采用涵盖土壤重金属含量、浸出浓度和毒性的土壤重金属环境风险评价方法对修复效果进行评价。结果表明,EGTA对Cu和Cd的洗脱率较高,可显著降低Zn和Cd浸出浓度。增加淋洗时间有助于提高Cu、Zn和Cd洗脱率并降低其浸出浓度,但提高了Pb浸出浓度。随着液固比的增加,Zn和Pb洗脱率呈上升趋势,Cd洗脱率呈下降趋势,Cu洗脱率先提高后下降;Cu、Zn和Cd浸出浓度呈下降趋势,而Pb浸出浓度呈上升趋势。TSP钝化大幅度削减了Pb浸出浓度。总环境风险削减率(β)与EGTA投加量、液固比及TSP投加量呈二次方关系,当EGTA投加量为1.0 g·L~(-1),液固比为10,TSP投加量w为2%时,β为62.80%,与验证实验结果相近,表明模型具有较好的模拟和预测能力。提高EGTA投加量和液固比可以大幅度降低Cu、Zn和Cd的环境风险,TSP钝化处理对Pb环境风险的削减作用较好,EGTA投加量与液固比以及EGTA投加量与TSP投加量对β表现为协同作用。
Considering that chelant-enhance washing may increase the activity of residual metals in soil, the risk reduction of heavy metal-contaminated soil by integrated soil washing with immobilization was investigated. Ethylenebis(oxyethylenenitrilo) tetraacetic acid(EGTA) and triple super phosphate(TSP) were used as washing and stabilization agent, respectively, to remediate Cu-, Zn-, Pb-and Cd-contaminated yellow brown soil. The effects of EGTA dosage, washing time, liquid-to-solid ratio and TSP dosage on heavy metal removal rate and leaching concentration were explored. The relationship between the environmental risk reduction rate and EGTA dosage, liquid-to-solid ratio and TSP dosage was fitted by response surface method(RSM). The remediation performance was evaluated by the environmental risk assessment method involving heavy metal content in soil, leaching concentration and toxicity. The results show that with EGTA enhanced-washing, the elution rate of Cu and Cd was relatively higher and the leaching concentration of Zn and Cd was significantly reduced. By increasing the washing time, the removal rate of Cu, Zn, Cd was improved, while the leaching concentration declined. However, the leaching concentration of Pb was increased. With the increase of liquid-to-solid ratio, the removal rate of Zn and Pb was increased, while that for Cd was decreased and for Cu was firstly increased and then decreased. Meanwhile, the leaching concentration of Cu, Zn and Cd was decreased while for Pb was increased. The leaching concentration of Pb was significantly reduced by the passivation of TSP. The total environmental risk reduction rate(β) had a significant quadratic relationship with the EGTA dosage, liquid-to-solid ratio and TSP dosage. The model results are similar to the verification experiment results when the liquid-to-solid ratio, EGTA, TSP and β were 10, 1.0 g·L~(-1), 2% and 62.80%, respectively, which indicate that the model has good simulation and prediction ability. The environmental risk of Cu, Zn, and Cd could be significantly reduced by increasing the EGTA dosage and liquid-to-solid ratio. The passivation of TSP possessed a positive effect on the environmental risk reduction of Pb. In addition, the synergistic effect on β was observed between EGTA dosage and liquid-to-solid ratio, as well as EGTA and TSP dosage.
Considering that chelant-enhance washing may increase the activity of residual metals in soil, the risk reduction of heavy metal-contaminated soil by integrated soil washing with immobilization was investigated. Ethylenebis(oxyethylenenitrilo) tetraacetic acid(EGTA) and triple super phosphate(TSP) were used as washing and stabilization agent, respectively, to remediate Cu-, Zn-, Pb-and Cd-contaminated yellow brown soil. The effects of EGTA dosage, washing time, liquid-to-solid ratio and TSP dosage on heavy metal removal rate and leaching concentration were explored. The relationship between the environmental risk reduction rate and EGTA dosage, liquid-to-solid ratio and TSP dosage was fitted by response surface method(RSM). The remediation performance was evaluated by the environmental risk assessment method involving heavy metal content in soil, leaching concentration and toxicity. The results show that with EGTA enhanced-washing, the elution rate of Cu and Cd was relatively higher and the leaching concentration of Zn and Cd was significantly reduced. By increasing the washing time, the removal rate of Cu, Zn, Cd was improved, while the leaching concentration declined. However, the leaching concentration of Pb was increased. With the increase of liquid-to-solid ratio, the removal rate of Zn and Pb was increased, while that for Cd was decreased and for Cu was firstly increased and then decreased. Meanwhile, the leaching concentration of Cu, Zn and Cd was decreased while for Pb was increased. The leaching concentration of Pb was significantly reduced by the passivation of TSP. The total environmental risk reduction rate(β) had a significant quadratic relationship with the EGTA dosage, liquid-to-solid ratio and TSP dosage. The model results are similar to the verification experiment results when the liquid-to-solid ratio, EGTA, TSP and β were 10, 1.0 g·L~(-1), 2% and 62.80%, respectively, which indicate that the model has good simulation and prediction ability. The environmental risk of Cu, Zn, and Cd could be significantly reduced by increasing the EGTA dosage and liquid-to-solid ratio. The passivation of TSP possessed a positive effect on the environmental risk reduction of Pb. In addition, the synergistic effect on β was observed between EGTA dosage and liquid-to-solid ratio, as well as EGTA and TSP dosage.
引文
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[6] DERMONT G,BERGERON M,MERCIER G,et al.Soil Washing for Metal Removal:A Review of Physical/Chemical Technologies and Field Applications[J].Journal of Hazardous Materials,2008,152(1):1-31.
[7] WEI M,CHEN J J,WANG X W.Removal of Arsenic and Cadmium With Sequential Soil Washing Techniques Using Na2-EDTA,Oxalic and Phosphoric Acid:Optimization Conditions,Removal Effectiveness and Ecological Risks[J].Chemosphere,2016,156:252-261.
[8] BEIYUAN J Z,TSANG D C W,VALIX M,et al.Combined Application of EDDS and EDTA for Removal of Potentially Toxic Elements Under Multiple Soil Washing Schemes[J].Chemosphere,2018,205:178-187.
[9] 祝振球,周静,徐磊,等.不同重金属钝化材料对土壤胶体的影响[J].生态与农村环境学报,2017,33(2):188-192.[ZHU Zhen-qiu,ZHOU Jing,XU Lei,et al.Effects of Different Heavy Metal Amendments on Soil Colloid[J].Journal of Ecology and Rural Environment,2017,33(2):188-192.]
[10] HOU D Y,AL-TABBAA A,GUTHRIE P,et al.Using a Hybrid LCA Method to Evaluate the Sustainability of Sediment Remediation at the London Olympic Park[J].Journal of Cleaner Production,2014,83:87-95.
[11] ZHAI X Q,LI Z W,HUANG B,et al.Remediation of Multiple Heavy Metal-Contaminated Soil Through the Combination of Soil Washing and in Situ Immobilization[J].The Science of the Total Environment,2018,635:92-99.
[12] 尹雪,陈家军,吕策.螯合剂复配对实际重金属污染土壤洗脱效率影响及形态变化特征[J].环境科学,2014,35(2):733-739.[YIN Xue,CHEN Jia-jun,Lü Ce.Impact of Compounded Chelants on Removal of Heavy Metals and Characteristics of Morphologic Change in Soil From Heavy Metals Contaminated Sites[J].Environmental Science,2014,35(2):733-739.]
[13] GUO X F,WEI Z B,WU Q T,et al.Effect of Soil Washing With Only Chelators or Combining With Ferric Chloride on Soil Heavy Metal Removal and Phytoavailability:Field Experiments[J].Chemosphere,2016,147:412-419.
[14] 冯静,张增强,李念,等.铅锌厂重金属污染土壤的螯合剂淋洗修复及其应用[J].环境工程学报,2015,9(11):5617-5625.[FENG Jing,ZHANG Zeng-qiang,LI Nian,et al.Washing of Heavy Metal Contaminated Soil Around a Lead-Zinc Smelter by Several Chelating Agents and the Leached Soil Utilization[J].Chinese Journal of Environmental Engineering,2015,9(11):5617-5625.]
[15] 陈亚慧,李君,王明新,等.EGTA和酒石酸对蓖麻Cd胁迫与积累的调控作用[J].西北植物学报,2014,34(5):1025-1031.[CHEN Ya-hui,LI Jun,WANG Ming-xin,et al.Regulation of EGTA and Tartaric Acid on Cd Stress and Accumulation in Ricinus communis L.[J].Acta Botanica Boreali-Occidentalia Sinica,2014,34(5):1025-1031.]
[16] WANG G Y,ZHANG S R,XU X X,et al.Heavy Metal Removal by GLDA Washing:Optimization,Redistribution,Recycling,and Changes in Soil Fertility[J].Science of the Total Environment,2016,569/570:557-568.
[17] UDOVIC M,LESTAN D.Pb,Zn and Cd Mobility,Availability and Fractionation in Aged Soil Remediated by EDTA Leaching[J].Chemosphere,2009,74(10):1367-1373.
[18] TSANG D C W,OLDS W E,WEBER P.Residual Leachability of CCA-Contaminated Soil After Treatment With Biodegradable Chelating Agents and Lignite-Derived Humic Substances[J].Journal of Soils and Sediments,2013,13(5):895-905.
[19] IM J,YANG K,JHO E H,et al.Effect of Different Soil Washing Solutions on Bioavailability of Residual Arsenic in Soils and Soil Properties[J].Chemosphere,2015,138:253-258.
[20] PARK J H,BOLAN N S,CHUNG J W,et al.Environmental Monitoring of the Role of Phosphate Compounds in Enhancing Immobilization and Reducing Bioavailability of Lead in Contaminated Soils[J].Journal of Environmental Monitoring,2011,13(8):2234-2242.
[21] 祝振球,周静,徐磊,等.模拟酸雨对微米和纳米羟基磷灰石稳定化污染土壤的铜和镉淋溶效应[J].生态与农村环境学报,2017,33(3):265-269.[ZHU Zhen-qiu,ZHOU Jing,XU Lei,et al.Release of Cu and Cd From Contaminated Soil Amended by Nanoparticle and Microparticle Hydroxyapatite in the Condition of Acid Deposition[J].Journal of Ecology and Rural Environment,2017,33(3):265-269.]
[22] 荀志祥,王世泽,王明新,等.超声强化EDDS/EGTA淋洗修复重金属污染土壤[J].环境工程学报,2018,12(6):1766-1774.[XUN Zhi-xiang,WANG Shi-ze,WANG Ming-xin,et al.Remediation of Heavy Metal Contaminated Soil by Ultrasound-Enhanced Washing With EDDS and EGTA[J].Chinese Journal of Environmental Engineering,2018,12(6):1766-1774.]
[23] 张春雷,费小通,李婷,等.利用超声波辅助去除污染土壤中重金属的研究[J].环境科学与技术,2014,37(增刊 1):121-124.[ZHANG Chun-lei,FEI Xiao-tong,LI Ting,et al.Ultrasound Assisted Removal of Heavy Metals From Contaminated Soil[J].Environmental Science & Technology,2014,37(Suppl.1):121-124.]
[24] LIANG Y,CAO X D,ZHAO L,et al.Biochar- and Phosphate-Induced Immobilization of Heavy Metals in Contaminated Soil and Water:Implication on Simultaneous Remediation of Contaminated Soil and Groundwater[J].Environmental Science and Pollution Research,2014,21(6):4665-4674.
[25] 鲁如坤.土壤农业化学分析方法[M].北京:中国农业科技出版社,2000:205-214.
[26] 中国环境监测总站.中国土壤元素背景值[M].北京:中国环境科学出版社,1990:93-493.
[27] GB/T 14848—2017,地下水质量标准[S].[GB/T 14848-2017,Standard for Groundwater Quality[S].]
[28] SHAHEEN S M,TSADILAS C D,RINKLEBE J.A Review of the Distribution Coefficients of Trace Elements in Soils:Influence of Sorption System,Element Characteristics,and Soil Colloidal Properties[J].Advances in Colloid and Interface Science,2013,201/202:43-56.
[29] LABANOWSKI J,MONNA F,BERMOND A,et al.Kinetic Extractions to Assess Mobilization of Zn,Pb,Cu,and Cd in a Metal-Contaminated Soil:EDTA vs.Citrate[J].Environmental Pollution,2008,152(3):693-701.
[30] WU Q,CUI Y R,LI Q L,et al.Effective Removal of Heavy Metals From Industrial Sludge With the Aid of a Biodegradable Chelating Ligand GLDA[J].Journal of Hazardous Materials,2015,283:748-754.
[31] CAO X D,MA L Q,RHUE D R,et al.Mechanisms of Lead,Copper,and Zinc Retention by Phosphate Rock[J].Environmental Pollution,2004,131(3):435-444.
[32] BROWN S,CHRISTENSEN B,LOMBI E,et al.An Inter-Laboratory Study to Test the Ability of Amendments to Reduce the Availability of Cd,Pb,and Zn in Situ[J].Environmental Pollution,2005,138(1):34-45.
[33] MIRETZKY P,FERNANDEZ-CIRELLI A.Phosphates for Pb Immobilization in Soils:A Review[J].Environmental Chemistry Letters,2008,6(3):121-133.
[2] JINGZI B Y,LI J S,TSANG D C W,et al.Fate of Arsenic Before and After Chemical-Enhanced Washing of an Arsenic-Containing Soil in Hong Kong[J].Science of the Total Environment,2017,599/600:679-688.
[3] 陆素芬,宋波,伏凤艳,等.南丹矿业活动影响区蔬菜重金属含量及健康风险[J].生态与农村环境学报,2016,32(3):478-485.[LU Su-fen,SONG Bo,FU Feng-yan,et al.Heavy Metal Content in Vegetable and Its Health Risk as Affected by Mining Activities in Nandan County[J].Journal of Ecology and Rural Environment,2016,32(3):478-485.]
[4] BOLAN N,KUNHIKRISHNAN A,THANGARAJAN R,et al.Remediation of Heavy Metal(Loid)s Contaminated Soils:To Mobilize or to Immobilize?[J].Journal of Hazardous Materials,2014,266:141-166.
[5] JIANG J P,WU L H,LI N,et al.Effects of Multiple Heavy Metal Contamination and Repeated Phytoextraction by Sedum plumbizincicola on Soil Microbial Properties[J].European Journal of Soil Biology,2010,46(1):18-26.
[6] DERMONT G,BERGERON M,MERCIER G,et al.Soil Washing for Metal Removal:A Review of Physical/Chemical Technologies and Field Applications[J].Journal of Hazardous Materials,2008,152(1):1-31.
[7] WEI M,CHEN J J,WANG X W.Removal of Arsenic and Cadmium With Sequential Soil Washing Techniques Using Na2-EDTA,Oxalic and Phosphoric Acid:Optimization Conditions,Removal Effectiveness and Ecological Risks[J].Chemosphere,2016,156:252-261.
[8] BEIYUAN J Z,TSANG D C W,VALIX M,et al.Combined Application of EDDS and EDTA for Removal of Potentially Toxic Elements Under Multiple Soil Washing Schemes[J].Chemosphere,2018,205:178-187.
[9] 祝振球,周静,徐磊,等.不同重金属钝化材料对土壤胶体的影响[J].生态与农村环境学报,2017,33(2):188-192.[ZHU Zhen-qiu,ZHOU Jing,XU Lei,et al.Effects of Different Heavy Metal Amendments on Soil Colloid[J].Journal of Ecology and Rural Environment,2017,33(2):188-192.]
[10] HOU D Y,AL-TABBAA A,GUTHRIE P,et al.Using a Hybrid LCA Method to Evaluate the Sustainability of Sediment Remediation at the London Olympic Park[J].Journal of Cleaner Production,2014,83:87-95.
[11] ZHAI X Q,LI Z W,HUANG B,et al.Remediation of Multiple Heavy Metal-Contaminated Soil Through the Combination of Soil Washing and in Situ Immobilization[J].The Science of the Total Environment,2018,635:92-99.
[12] 尹雪,陈家军,吕策.螯合剂复配对实际重金属污染土壤洗脱效率影响及形态变化特征[J].环境科学,2014,35(2):733-739.[YIN Xue,CHEN Jia-jun,Lü Ce.Impact of Compounded Chelants on Removal of Heavy Metals and Characteristics of Morphologic Change in Soil From Heavy Metals Contaminated Sites[J].Environmental Science,2014,35(2):733-739.]
[13] GUO X F,WEI Z B,WU Q T,et al.Effect of Soil Washing With Only Chelators or Combining With Ferric Chloride on Soil Heavy Metal Removal and Phytoavailability:Field Experiments[J].Chemosphere,2016,147:412-419.
[14] 冯静,张增强,李念,等.铅锌厂重金属污染土壤的螯合剂淋洗修复及其应用[J].环境工程学报,2015,9(11):5617-5625.[FENG Jing,ZHANG Zeng-qiang,LI Nian,et al.Washing of Heavy Metal Contaminated Soil Around a Lead-Zinc Smelter by Several Chelating Agents and the Leached Soil Utilization[J].Chinese Journal of Environmental Engineering,2015,9(11):5617-5625.]
[15] 陈亚慧,李君,王明新,等.EGTA和酒石酸对蓖麻Cd胁迫与积累的调控作用[J].西北植物学报,2014,34(5):1025-1031.[CHEN Ya-hui,LI Jun,WANG Ming-xin,et al.Regulation of EGTA and Tartaric Acid on Cd Stress and Accumulation in Ricinus communis L.[J].Acta Botanica Boreali-Occidentalia Sinica,2014,34(5):1025-1031.]
[16] WANG G Y,ZHANG S R,XU X X,et al.Heavy Metal Removal by GLDA Washing:Optimization,Redistribution,Recycling,and Changes in Soil Fertility[J].Science of the Total Environment,2016,569/570:557-568.
[17] UDOVIC M,LESTAN D.Pb,Zn and Cd Mobility,Availability and Fractionation in Aged Soil Remediated by EDTA Leaching[J].Chemosphere,2009,74(10):1367-1373.
[18] TSANG D C W,OLDS W E,WEBER P.Residual Leachability of CCA-Contaminated Soil After Treatment With Biodegradable Chelating Agents and Lignite-Derived Humic Substances[J].Journal of Soils and Sediments,2013,13(5):895-905.
[19] IM J,YANG K,JHO E H,et al.Effect of Different Soil Washing Solutions on Bioavailability of Residual Arsenic in Soils and Soil Properties[J].Chemosphere,2015,138:253-258.
[20] PARK J H,BOLAN N S,CHUNG J W,et al.Environmental Monitoring of the Role of Phosphate Compounds in Enhancing Immobilization and Reducing Bioavailability of Lead in Contaminated Soils[J].Journal of Environmental Monitoring,2011,13(8):2234-2242.
[21] 祝振球,周静,徐磊,等.模拟酸雨对微米和纳米羟基磷灰石稳定化污染土壤的铜和镉淋溶效应[J].生态与农村环境学报,2017,33(3):265-269.[ZHU Zhen-qiu,ZHOU Jing,XU Lei,et al.Release of Cu and Cd From Contaminated Soil Amended by Nanoparticle and Microparticle Hydroxyapatite in the Condition of Acid Deposition[J].Journal of Ecology and Rural Environment,2017,33(3):265-269.]
[22] 荀志祥,王世泽,王明新,等.超声强化EDDS/EGTA淋洗修复重金属污染土壤[J].环境工程学报,2018,12(6):1766-1774.[XUN Zhi-xiang,WANG Shi-ze,WANG Ming-xin,et al.Remediation of Heavy Metal Contaminated Soil by Ultrasound-Enhanced Washing With EDDS and EGTA[J].Chinese Journal of Environmental Engineering,2018,12(6):1766-1774.]
[23] 张春雷,费小通,李婷,等.利用超声波辅助去除污染土壤中重金属的研究[J].环境科学与技术,2014,37(增刊 1):121-124.[ZHANG Chun-lei,FEI Xiao-tong,LI Ting,et al.Ultrasound Assisted Removal of Heavy Metals From Contaminated Soil[J].Environmental Science & Technology,2014,37(Suppl.1):121-124.]
[24] LIANG Y,CAO X D,ZHAO L,et al.Biochar- and Phosphate-Induced Immobilization of Heavy Metals in Contaminated Soil and Water:Implication on Simultaneous Remediation of Contaminated Soil and Groundwater[J].Environmental Science and Pollution Research,2014,21(6):4665-4674.
[25] 鲁如坤.土壤农业化学分析方法[M].北京:中国农业科技出版社,2000:205-214.
[26] 中国环境监测总站.中国土壤元素背景值[M].北京:中国环境科学出版社,1990:93-493.
[27] GB/T 14848—2017,地下水质量标准[S].[GB/T 14848-2017,Standard for Groundwater Quality[S].]
[28] SHAHEEN S M,TSADILAS C D,RINKLEBE J.A Review of the Distribution Coefficients of Trace Elements in Soils:Influence of Sorption System,Element Characteristics,and Soil Colloidal Properties[J].Advances in Colloid and Interface Science,2013,201/202:43-56.
[29] LABANOWSKI J,MONNA F,BERMOND A,et al.Kinetic Extractions to Assess Mobilization of Zn,Pb,Cu,and Cd in a Metal-Contaminated Soil:EDTA vs.Citrate[J].Environmental Pollution,2008,152(3):693-701.
[30] WU Q,CUI Y R,LI Q L,et al.Effective Removal of Heavy Metals From Industrial Sludge With the Aid of a Biodegradable Chelating Ligand GLDA[J].Journal of Hazardous Materials,2015,283:748-754.
[31] CAO X D,MA L Q,RHUE D R,et al.Mechanisms of Lead,Copper,and Zinc Retention by Phosphate Rock[J].Environmental Pollution,2004,131(3):435-444.
[32] BROWN S,CHRISTENSEN B,LOMBI E,et al.An Inter-Laboratory Study to Test the Ability of Amendments to Reduce the Availability of Cd,Pb,and Zn in Situ[J].Environmental Pollution,2005,138(1):34-45.
[33] MIRETZKY P,FERNANDEZ-CIRELLI A.Phosphates for Pb Immobilization in Soils:A Review[J].Environmental Chemistry Letters,2008,6(3):121-133.
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