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石油烃 (PHC) 是目前环境中广泛存在的有机污染物,是多种烃类 (正烷烃、支链烷烃、环烷烃、芳烃) 和少量其他有机物的混合物[1]。PHC进入土壤后,不仅会破坏土壤结构,与无机氮、磷结合并限制硝化作用和脱磷酸作用,减少土壤中有效氮、磷等养分的含量,还会通过挥发或食物链富集等途径对人群健康构成潜在风险[2]。因此,PHC污染土壤的修复治理迫在眉睫[3]。化学氧化剂过硫酸盐 (PS) 因其在环境中存在时间长、适用pH范围广、氧化性强等优势被广泛应用于有机污染土壤修复领域。PS可以在水中分解产生强氧化剂S2O82−,经活化后会产生氧化性更强的SO4−·,能够在广泛的环境条件下转化各种环境污染物[4]。
有机污染物进入土壤后往往以“快”“慢”“极慢”等解吸组分形式存在[5],由于“快”解吸组分易被氧化,氧化后污染物往往以“慢”“极慢”等解吸组分形式存在[6],难以进一步去除,化学氧化末期往往会出现拖尾现象[7-8]。虽然投加过量药剂可以提高PHC降解效率,但也会增加修复成本。因此,化学氧化和其他修复技术的联合应用备受关注[9],如已有研究表明化学氧化与微生物联合处理能够更高效地去除土壤中的PHC[10-12]。由于缺氧条件下微生物对有机污染物的降解效率较低,目前与微生物联合降解有机污染物的研究多在好氧条件下进行[13],然而,通过降解参数优化 (如营养物质、电子受体等) ,微生物的缺氧降解效率会明显提升[14-16]。此外,深层有机污染土壤往往处于缺氧环境[17],因此探究缺氧条件下化学氧化与微生物联合修复PHC污染土壤具有重要意义。
由于PS氧化后土壤中残留的PHC以“慢”“极慢”等解吸组分形式存在,生物有效性更低,限制了其进一步生物降解[11]。加入表面活性剂可以增强土壤中PHC的解吸能力,提高其生物有效性[18-19]。常见的表面活性剂增效修复技术使用单一阴离子或非离子表面活性剂,单一阴离子表面活性剂会发生沉淀作用,非离子表面活性剂则易被土壤吸附,而混合表面活性剂体系既能减少表面活性剂在土壤表面的吸附,提高解吸效率,又能使得洗脱液中污染物浓度和表面活性剂浓度对微生物降解产生正效应,是一种更有效的修复方式[20]。但表面活性剂对PS氧化后土壤中微生物以及PHC缺氧生物降解的影响尚不清楚。因此,本研究将通过加入不同质量浓度和质量比的SDBS和Tween 80,探究其对PS氧化后土壤中PHC解吸、土著微生物群落结构和丰度、PHC缺氧降解的影响,为深层石油污染土壤的微生物修复提供参考。
表面活性剂SDBS和Tween 80强化过硫酸盐氧化后土壤中石油烃的缺氧生物降解
Surfactants SDBS and Tween 80 enhance anoxic biodegradation of petroleum hydrocarbons (PHC) in soil pretreated with persulfate
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摘要: 化学氧化和微生物联合修复是去除土壤中石油烃 (PHC) 的有效技术,但氧化后土壤中残留PHC的生物有效性较低,难以进一步生物降解。向过硫酸盐 (PS) 氧化后的土壤中加入不同质量浓度和质量比的表面活性剂十二烷基苯磺酸钠 (SDBS) 和聚氧乙烯山梨醇酐单油酸酯 (Tween 80) ,探究其对PS氧化后土壤中PHC解吸、土著微生物群落结构和丰度、PHC缺氧降解的影响。结果表明,缺氧条件下PS氧化和微生物联合降解去除了土壤中30.84%的ΣPHC (C10~C30) 。向PS氧化后土壤中加入SDBS和Tween 80能够有效促进PHC解吸,解吸效果随表面活性剂质量浓度和混合体系中Tween 80比例的增加而增加。加入3 000 mg·L−1表面活性剂继续缺氧培养120 d后,氧化后土壤中Firmicutes和Proteobacteria的总数量较对照组减少了2.13~2.58个数量级,抑制了土壤中PHC的缺氧降解。加入800 mg·L−1表面活性剂后,土壤中Firmicutes和Proteobacteria的总数量较对照组增加了0.17~0.81个数量级,促进了PHC的缺氧降解,在SDBS∶Tween 80=1∶3时ΣPHC残留率最低 (较对照组降低了15.80%) 。本研究结果可为深层石油污染土壤的微生物修复提供参考。Abstract: Chemical oxidation combined with biodegradation is an effective technology for removing petroleum hydrocarbons (PHC) from soil. However, the residual PHC in soil after oxidation is difficult to be further biodegraded due to their low bioavailability. The surfactants of sodium dodecyl benzene sulfonate (SDBS) and polyoxyethylene sorbitan monooleate (Tween 80) with different doses and mass ratios were added to the soil pretreated with persulfate (PS), to investigate their effect on PHC desorption, indigenous microbial community composition and abundance, PHC anoxic biodegradation. The results showed that 30.84% of ΣPHC(C10~C30) in soil were removed by PS oxidation combined with anoxic biodegradation. SDBS and Tween 80 were added to the soil pretreated with PS had effectively promoted the desorption of PHC, the effect increased with the increase of surfactant’s concentration and the proportion of Tween 80 in the mixed system. After 120 d of continued anoxic incubation, the total amount of Firmicutes and Proteobacteria in soil added surfactants with the concentration of 3 000 mg·L−1 decreased by 2.13~2.58 orders of magnitude compared with the control treatment, which inhibited the anoxic biodegradation of PHC. The total amount of Firmicutes and Proteobacteria in soil added surfactants with the concentration of 800 mg·L−1 increased by 0.17~0.81 orders of magnitude compared with the control treatment, which promoted the anoxic biodegradation of PHC, the residual rate of ΣPHC was lowest at SDBS:Tween 80=1:3 (15.80% lower than the control group). This study can provide a reference for the microbial remediation of subsurface soil contaminated with PHC.
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Key words:
- surfactants /
- petroleum hydrocarbons /
- anoxic biodegradation /
- chemical oxidation
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表 1 土壤中PHC质量分数
Table 1. Mass fraction of PHC in soil
PHC组分 组名 原土PHC质量
分数/mg·kg−1原土灭菌后PHC
质量分数/mg·kg−1原土经PS氧化30 d后PHC
质量分数/mg·kg−1灭菌土经PS氧化30 d后
PHC质量分数/mg·kg−1C10~C16 F1 251.64±3.94 49.14±7.72 149.90±22.45 32.03±1.17 C17~C23 F2 524.74±34.97 326.13±33.77 371.47±41.07 258.65±3.89 C24~C30 F3 67.37±0.21 66.12±0.74 62.14±3.95 58.65±0.28 C31~C40 — 22.41±6.47 20.66±5.38 — — ΣPHC(C10~C30) — 843.75±30.82 441.39±26.79 583.51±59.89 349.33±5.34 -
[1] 刘自力, 王红旗, 孔德康, 等. 不同植物-微生物联合修复体系下石油烃的降解[J]. 环境工程学报, 2018, 12(1): 190-197. doi: 10.12030/j.cjee.201704016 [2] 周启星, 展海银. 石油及石化污染场地生物修复技术进展与展望[J]. 应用技术学报, 2021, 21(4): 285-292. [3] 李晓晶, 赵倩, 张月勇, 等. 微生物燃料电池修复石油污染盐碱土壤[J]. 环境工程学报, 2017, 11(2): 1185-1191. doi: 10.12030/j.cjee.201509031 [4] TSITONAKI A, PETRI B, CRIMI M, et al. In situ chemical oxidation of contaminated soil and groundwater using persulfate: A review[J]. Critical Reviews in Environmental Science and Technology, 2010, 40(1): 55-91. doi: 10.1080/10643380802039303 [5] GOU Y L, ZHAO Q Y, YANG S C, et al. Enhanced degradation of polycyclic aromatic hydrocarbons in aged subsurface soil using integrated persulfate oxidation and anoxic biodegradation[J]. Chemical Engineering Journal, 2020, 394: 125040. doi: 10.1016/j.cej.2020.125040 [6] HATZINGER P B, ALEXANDER M. Effect of aging of chemicals in soil on their biodegradability and extractability[J]. Environmental Science & Technology, 1995, 29(2): 537-545. [7] CASSIDY D, NORTHUP A, HAMPTON D. The effect of three chemical oxidants on subsequent biodegradation of 2, 4-dinitrotoluene (DNT) in batch slurry reactors[J]. Journal of Chemical Technology and Biotechnology, 2009, 84(6): 820-826. doi: 10.1002/jctb.2140 [8] CHEN K F, CHANG Y C, CHIOU W T. Remediation of diesel-contaminated soil using in situ chemical oxidation (ISCO) and the effects of common oxidants on the indigenous microbial community: a comparison study[J]. Journal of Chemical Technology and Biotechnology, 2016, 91(6): 1877-1888. doi: 10.1002/jctb.4781 [9] SAHL J, MUNAKATA-MARR J. The effects of in situ chemical oxidation on microbiological processes: A review[J]. Remediation Journal:The Journal of Environmental Cleanup Costs, Technologies & Techniques, 2006, 16(3): 57-70. [10] LI Y T, LI D, LAI L J, et al. Remediation of petroleum hydrocarbon contaminated soil by using activated persulfate with ultrasound and ultrasound/Fe[J]. Chemosphere, 2020, 238: 124657. doi: 10.1016/j.chemosphere.2019.124657 [11] LOMINCHAR M A, SANTOS A, MIGUEL E, et al. Remediation of aged diesel contaminated soil by alkaline activated persulfate[J]. Science of the Total Environment, 2018, 622-623: 41-48. doi: 10.1016/j.scitotenv.2017.11.263 [12] ZHANG B W, GUO Y, HUO J Y, et al. Combining chemical oxidation and bioremediation for petroleum polluted soil remediation by BC-nZVI activated persulfate[J]. Chemical Engineering Journal, 2020, 382: 123055. doi: 10.1016/j.cej.2019.123055 [13] GHATTAS A K, FISCHER F, WICK A, et al. Anaerobic biodegradation of (emerging) organic contaminants in the aquatic environment[J]. Water Research, 2017, 116: 268-295. doi: 10.1016/j.watres.2017.02.001 [14] LU X Y, LI B, ZHANG T, et al. Enhanced anoxic bioremediation of PAHs-contaminated sediment[J]. Bioresource Technology, 2012, 104: 51-58. doi: 10.1016/j.biortech.2011.10.011 [15] MEDINA R, GARA P M D, FERNÁNDEZ-GONZÁLEZ A J, et al. Remediation of a soil chronically contaminated with hydrocarbons through persulfate oxidation and bioremediation[J]. Science of the Total Environment, 2018, 618: 518-530. doi: 10.1016/j.scitotenv.2017.10.326 [16] YANG S C, GOU Y L, SONG Y, et al. Enhanced anoxic biodegradation of polycyclic aromatic hydrocarbons (PAHs) in a highly contaminated aged soil using nitrate and soil microbes[J]. Environmental Earth Sciences, 2018, 77: 432. doi: 10.1007/s12665-018-7629-6 [17] FIERER N, SCHIMEL J P, HOLDEN P A. Variations in microbial community composition through two soil depth profiles[J]. Soil Biology and Biochemistry, 2003, 35(1): 167-176. doi: 10.1016/S0038-0717(02)00251-1 [18] 马浩, 刘元元, 肖文燕, 等. 表面活性剂CMC对石油烃污染土壤的增溶[J]. 环境工程学报, 2016, 10(12): 7333-7338. doi: 10.12030/j.cjee.201507133 [19] SEMPLE K T, MORRISS A W J, PATON G I. Bioavailability of hydrophobic organic contaminants in soils: fundamental concepts and techniques for analysis[J]. European Journal of Soil Science, 2003, 54(4): 809-818. doi: 10.1046/j.1351-0754.2003.0564.x [20] 陈巧超, 王一宁, 董旭斌. 阴-非混合表面活性剂增效修复有机污染土壤的影响因素研究[J]. 科学技术创新, 2021(20): 52-53. doi: 10.3969/j.issn.1673-1328.2021.20.022 [21] 赵倩云, 苟雅玲, 杨苏才, 等. 硫酸盐对老化土壤中多环芳烃厌氧降解的影响[J]. 环境科学与技术, 2018, 41(12): 200-205. doi: 10.19672/j.cnki.1003-6504.2018.12.029 [22] 刘志号. 缺氧条件下温度和表面活性剂对土壤中多环芳烃微生物降解的影响[D]. 北京: 轻工业环境保护研究所, 2021. [23] 李佳斌. 土壤中石油烃的芬顿氧化实验研究[D]. 北京: 轻工业环境保护研究所, 2016. [24] GOU Y L, YANG S C, CHENG Y J, et al. Enhanced anoxic biodegradation of polycyclic aromatic hydrocarbons (PAHs) in aged soil pretreated by hydrogen peroxide[J]. Chemical Engineering Journal, 2019, 356: 524-533. doi: 10.1016/j.cej.2018.09.059 [25] FREY B, RIME T, PHILLIPS M, et al. Microbial diversity in European alpine permafrost and active layers[J]. FEMS Microbiology Ecology, 2016, 92(3): fiw018. doi: 10.1093/femsec/fiw018 [26] LEI Y J, ZHANG J, TIAN Y, et al. Enhanced degradation of total petroleum hydrocarbons in real soil by dual-frequency ultrasound-activated persulfate[J]. Science of the Total Environment, 2020, 748: 141414. doi: 10.1016/j.scitotenv.2020.141414 [27] BARTLETT C K, SLAWSON R M, THOMSON N R. Response of sulfate-reducing bacteria and supporting microbial community to persulfate exposure in a continuous flow system[J]. Environmental Science:Processes & Impacts, 2019, 21(7): 1193-1203. [28] TIAN W, YAO J, LIU R P, et al. Effect of natural and synthetic surfactants on crude oil biodegradation by indigenous strains[J]. Ecotoxicology and Environmental Safety, 2016, 129: 171-179. doi: 10.1016/j.ecoenv.2016.03.027 [29] WU M L, WU J L, ZHANG X H, et al. Effect of bioaugmentation and biostimulation on hydrocarbon degradation and microbial community composition in petroleum-contaminated loessal soil[J]. Chemosphere, 2019, 237: 124456. doi: 10.1016/j.chemosphere.2019.124456 [30] GRAY N D, SHERRY A, HUBERT C, et al. Chapter 5- Methanogenic degradation of petroleum hydrocarbons in subsurface environments: remediation, heavy oil formation, and energy recovery[J]. Advances in Applied Microbiology, 2010, 72: 137-161. [31] 张秀霞, 熊鑫, 郭鹏, 等. SDBS残留对微生物修复石油污染土壤的影响[J]. 石油学报(石油加工), 2021, 37(5): 1167-1173. [32] KOSTKA J E, PRAKASH O, OVERHOLT W A, et al. Hydrocarbon-degrading bacteria and the bacterial community response in Gulf of Mexico beach sands impacted by the deepwater horizon oil spill[J]. Applied and Environmental Microbiology, 2011, 77(22): 7962-7974. doi: 10.1128/AEM.05402-11 [33] CHEN F, LI X X, ZHU Q L, et al. Bioremediation of petroleum-contaminated soil enhanced by aged refuse[J]. Chemosphere, 2019, 222: 98-105. doi: 10.1016/j.chemosphere.2019.01.122