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1.
黄土地区石油污染土壤生物修复的强化技术初探   总被引:1,自引:0,他引:1  
以石油为典型污染物,在本次试验前期工作筛选保藏的众多优势石油降解细菌中选择4株降解能力突出的菌,对该4菌株(分别编号为A、B、C、D)进行随机混合构建优势降解菌群。结果表明:菌群A-C-D降解石油能力最强,3 d内原油的降解率达到了39.67%,比单菌除油率提高了13.21%;对该菌群的最佳投加配比进行确定,菌群的最佳接种配比为A∶C∶D=1∶2∶0.5,3 d内菌群A-C-D在不同接种配比情况下降解率变化范围为27.8%~44.2%,最高值与最低值相差16.4%,因此菌群间各菌必须维持在一定的数量配比的情况下才能达到理想的降解效果。对影响生物修复效果的环境因素,如营养物质(C、N、P)、表面活性剂、通氧量、电子受体等进行综合考虑,通过正交试验确定菌群A-C-D的最佳修复条件为:营养物质配比C∶N∶P为75∶8∶3,表面活性剂为0.5%,通气条件为六层纱布,电子受体H2O2的加入量为1.5%。在最佳修复条件下,3 d内原油的降解率达到61.46%,比自然条件修复下的除油率4.7%提高了56.76%,较只进行菌种强化时的最高除油率44.2%提高了约17%。  相似文献   

2.
为探索石油污染土壤的高效修复方法,从实验室保存的优势菌中筛选得到4株降油效果最佳菌,采用摇床和恒温培养箱培养,对含油量为5%的石油污染土壤进行微生物菌剂强化处理和环境强化实验。微生物菌剂强化结果表明:4种菌和除油效果最好的A、C、D混合菌3d可将石油烃依次降解24%、19.81%、22.55%、26.46%、39.67%;并对该菌群的最佳投加配比进行确定,A、C、D菌群数量的最佳配比为Nn:Nc:No=1:2:0.5,3d内菌群A、C、D在最佳接种配比情况下可将石油烃降解44.2%。环境强化实验结果表明:A、C、D菌群在最佳修复条件营养物质C:N:P为75:8:3、表面活性剂为0.5%、通气条件为6层纱布、电子受体H2O2的加入量为1.5%下,3d内石油烃降解61.46%,比自然条件下修复的除油率4.7%提高了56.76%,较只进行菌种强化时最高除油率44.2%提高了约17%。  相似文献   

3.
石油作为现当代最主要的能源受到越来越多的关注,但同时随着石油的大量开发和运输,土壤的石油污染问题日益严重。当前,关于石油污染土壤的修复技术主要有物理、化学和生物技术,生物修复技术指利用特定的生物(植物、动物、微生物)吸收、转化、降解或清除环境污染物,使污染的土壤恢复健康的生物措施,可分为植物修复、微生物修复、动物修复及联合修复。生物修复因其简便、高效、安全、低成本、无二次污染、对环境影响小等特点而被认为是最有生命力、最具代表性和最有价值的处理技术,且已成为近些年来主要的石油污染处理方法。本文主要介绍石油污染土壤现状及其生物修复技术,并对生物修复今后的研究重点进行展望。  相似文献   

4.
Fe~(2+)活化过硫酸盐在石油污染土壤中修复实验研究   总被引:1,自引:0,他引:1       下载免费PDF全文
硫酸根自由基的高级氧化技术以高效率、污染少等优点被广泛用于环境污染治理。本文以实际石油污染土壤为对象,运用该体系对土壤进行修复研究,分别从Na_2S_2O_8/Fe~(2+)摩尔比、体系pH值、Na_2S_2O_8/Fe~(2+)投加量等方面开展了实验研究。实验表明:当Na_2S_2O_8/Fe2+摩尔比为2∶3时,石油污染物的降解效果最好,体系的pH值对降解效果影响不大,1 g土壤中浓度为0.1 mol/L的过硫酸钠和硫酸亚铁溶液的最佳加入量为2 m L、3 m L时,对土壤的降解效果最为明显,故每吨污染土壤的添加量大约为2×10~6m L、3×10~6m L。  相似文献   

5.
生物曝气技术对石油类污染地下水的修复效果及去除机制   总被引:1,自引:0,他引:1  
针对东北某石油污染场地水文地质条件进行模拟,按照试验场地地层现状进行实验室缩放,研究微生物在含水层介质为砾砂、粗砂和中砂中的迁移速度以及含水层介质吸附的微生物量。选取苯和二甲苯作为目标石油污染物,研究生物曝气技术对被污染地下水的修复效果及其去除污染物的机制。实验结果表明:微生物在介质中的迁移速度从大到小为砾砂、粗砂、中砂;介质吸附微生物量的顺序从大到小为中砂、粗砂、砾砂;生物曝气4个月后,苯和二甲苯去除率分别为86.4%和81.7%,BS对中砂层中的苯和二甲苯去除效果好于砾砂层和粗砂层,苯的去除效果好于二甲苯。由挥发机制去除的污染物为46.24%,生物降解去除的污染物为36.98%,BS技术可以有效去除地下水中石油类污染物。  相似文献   

6.
不同坡度缓冲带滞缓径流及污染物去除定量化   总被引:8,自引:0,他引:8       下载免费PDF全文
吴建强 《水科学进展》2011,22(1):112-117
利用构建的东风港缓冲带现场试验基地和设计的径流流量测定装置,模拟上海地区农业面源污染物浓度和典型单次降雨历时及降雨量,对不同坡度缓冲带滞缓径流和农田氮磷污染物去除能力开展定量化试验研究。结果表明:相同植被缓冲带,坡度越小,其滞缓径流和土壤水力渗透的能力越强,19 m长的2%坡度缓冲带径流初始出水时间比5%坡度缓冲带延长了7.3 min,两者的渗流水量比值达到1.74;不同坡度缓冲带渗流氮磷污染物去除量显著高于径流,2%、3%、4%和5%坡度缓冲带对于氮磷污染物的渗流去除量与径流去除量的比值分别为2.32、2.15、1.82和1.64;坡度的变化对缓冲带净化面源氮磷污染物效果的影响显著,坡度越小,缓冲带渗流水量越大,其氮磷污染物的总去除率和单位面积去除负荷也越高,2%坡度缓冲带对氮磷污染的总去除率和单位面积污染去除负荷分别是5%坡度的1.56倍和1.66倍,2%坡度缓冲带对TN、NH3--N、TP的单位面积去除负荷均最高,分别达到0.661 g/m2、0.672 g/m2和0.044 g/m2。  相似文献   

7.
当地下水邂逅DNA:石油类有机污染及其生物降解   总被引:1,自引:0,他引:1  
地下水科学与工程研究发展到今日,已经成为一门涉及多个领域的综合性学科。地下水污染的控制和修复研究更需要跨学科的技术和知识支持,而生物修复作为一种高效低耗修复的技术成为环境领域的研究热点。微生物因其自身特性及其对污染的降解主导特征对确定有机物污染场地的永续修复具有重要意义。简要地综述了地下水有机污染及其原位修复、有机污染物和地下环境微生物的交互作用,进一步聚焦生物降解机制、生物修复和细菌研究。在此基础上以某石油污染场地地下水为例,进行了地下水中分离微生物菌株及其降解特征的实验研究。结果表明:放线菌降解效果最好,细菌和真菌次之;两两组合降解效果好于单菌,表明存在协同作用;不同菌株混合降解率较低,表明具有拮抗作用。通过动力学实验得出对TPH的降解符合一级反应动力学方程及其降解速度和降解半衰期。就微生物对有机组分降解而言,烷烃和总石油烃降解规律相似;难降解组分降解率低,后期因烷烃转化使其浓度升高;苯浓度变化不大。微生物活性实验表明:活菌总数和脱氢酶活性与降解率呈正相关变化。运用生理生化及分子生物学方法鉴定得出了具体的菌种。  相似文献   

8.
过硫酸盐已经被广泛用于土壤和地下水有机污染物的原位化学氧化修复。随着乙醇汽油的推广,乙醇汽油引起的地下水污染问题越来越严重,因此有必要去除该类污染物。前人研究乙醇汽油污染修复多数停留在自然修复技术,为了进一步探究去除地下水中乙醇汽油更为有效的技术手段,深入了解乙醇对降解苯系物(BTEX)存在的潜在风险,需要研究使用新的修复方法。文章通过批实验探索了过硫酸盐氧化法对乙醇汽油污染地下水的修复效果,以及Fe2+活化和过硫酸盐添加方式变化对乙醇汽油中苯系物(BTEX)和乙醇的去除影响。结果表明:活化后的过硫酸盐能够有效去除地下水中的BTEX,但会抑制BTEX的生物降解作用;当有乙醇存在时,过硫酸盐能够优先氧化BTEX,其去除速率明显高于乙醇,这与单纯生物降解作用相反。在过硫酸盐投注总量一定时,分批添加更有利于BTEX的去除,但对乙醇去除没有明显促进作用。该研究为过硫酸盐原位化学氧化技术在地下水乙醇汽油污染修复中的应用提供了重要参考。  相似文献   

9.
菌根真菌对土壤中有机污染物的修复研究   总被引:12,自引:0,他引:12  
菌根真菌是真菌与植物之间特殊的联合共生体,利用菌根真菌修复土壤,尤其是修复有机污染物污染的土壤,正成为一个崭新的研究方向。菌根真菌是土壤真菌的一种,但与土壤中放线菌和细菌等微生物相比,其对土壤中有机污染物具有更大的忍耐能力,并且能利用土壤中大多数持久性有机污染物作为碳源来获取能量。综述了近20年菌根真菌对土壤有机污染物降解研究,讨论了菌根真菌降解土壤有机污染物的可能机制,并探讨了从引入固氮菌、外源细菌两个方面对菌根调控以提高修复效果的可能性,为进一步研究菌根真菌生物降解土壤中持久性有机污染物、利用菌根植物修复有机污染土壤提供信息。  相似文献   

10.
李爽  文章  朱棋  刘慧  杨舒婷 《地球科学》2022,47(11):4176-4183
为使含水层中苯胺污染的原位修复过程高效安全且不产生二次污染,提出了一种电化学-水动力循环下的井内生物反应器修复地下水中苯胺的方法.在水动力循环系统的驱动下,评价了苯胺在水动力循环系统的挥发情况并且通过电化学手段提供氧气,井内生物反应器提供修复载体,在砂槽模拟的含水层体系中开展井内生物反应器降解苯胺的修复实验,并对生长曲线及含水层中苯胺修复进行了模拟.289 h的修复使体系内苯胺平均浓度从298 mg/L降低到132 mg/L,去除率为56.5%.运行过程中,监测点苯胺平均浓度在48 h内去除速率为1.10 mg/(L·h),48~72 h内去除速率为0.85 mg/(L·h),72 h到289 h内苯胺去除速率维持在0.65 mg/(L·h),氧化降解逐步减弱.该过程符合Michaelis-Menten方程,反应速率为:-6.71×10-7/(15+t)2.该修复系统是基于地下水动力循环技术的改进,有望应用于有机污染地下水修复.   相似文献   

11.
Biodegradation of petroleum hydrocarbons as a decontamination mechanism is a relatively slow process. This study aimed to investigate the impact of a tailored consortium of bacteria with higher capacities in biosurfactant production and biodegradation on the acceleration of the biodecontamination process. To this end, 18 biosurfactant producing bacteria were isolated from the crude oil-contaminated soil samples of Isfahan refinery, and the activity of the produced biosurfactants was measured in terms of surface tension reduction and emulsification E24 test. Then, the isolates screened for the biodegradation of kerosene hydrocarbons and chemical structure of the purified biosurfactants produced by the most efficient isolates were partially characterized. Next, the isolates were sorted based on their surfactant activity and biodegradation efficiency, and the higher ranked bacteria thus selected were utilized to form an efficient consortium removing hydrocarbons from the oil-contaminated soil samples in a slurry phase system. The consortium consisted of Bacillus subtilis tb1 and Pseudomonas aeruginosa species having the highest biodegradation capabilities and surface activities. The results revealed that the hydrocarbon removal efficiency of the consortium was at least 25 % higher than single species, and the final removal efficiency for the consortium could be reached in a considerably shorter time.  相似文献   

12.
A two-stage system for octachlorinated dibenzo-p-dioxin (OCDD)-contaminated soil remediation was developed. Soil washing using emulsified oil (EO) was applied in the first stage for OCDD extraction followed by the second stage of bioremediation using P. mendocina NSYSU for remaining OCDD biodegradation. The major tasks included (1) determination of optimal soil washing conditions for OCDD extraction by EO, (2) evaluation of feasibility of OCDD biodegradation by P. mendocina NSYSU under aerobic cometabolic conditions using EO as the primary substrate, and (3) assessment of the effectiveness of OCDD removal using the two-stage system. During the soil washing stage, EO with two different oil-to-water ratios (1:50 and 1:200) and pore volumes were tested with initial soil OCDD concentration of 21,000 µg/kg. Results indicate that EO could effectively improve the solubility and desorption of OCDD in soils. Up to 74% of OCDD removal could be obtained after washing with 60 PVs of EO and dilution factor of 50. After the soil washing process, enriched P. mendocina NSYSU solution was added into the reactor to enhance the aerobic biodegradation of remaining OCDD in soils. P. mendocina NSYSU could use adsorbed EO globules as substrates and caused significant OCDD degradation via the aerobic cometabolic mechanism. Approximately 82% of the remaining OCDD could be removed after 50 days of operation, and P. mendocina NSYSU played important roles in OCDD biodegradation. Up to 87% of OCDD was removed through the EO washing and biodegradation process. The two-stage system is a potential technology to remediate dioxin-contaminated soils.  相似文献   

13.
借助1∶25万云南省广南县幅土壤地球化学调查数据,并利用单因素方差分析、多重比较法以及地统计学方法,对岩溶区和非岩溶区土壤碳氮磷生态化学计量特征及其空间分布进行了对比分析。结果显示:广南县幅岩溶区土壤中有机碳(SOC)、全氮(TN)、全磷(TP)含量显著高于非岩溶区,而碳氮比(C∶N)、碳磷比(C∶P)、氮磷比(N∶P)显著低于非岩溶区;无论是岩溶区还是非岩溶区,表层(0~20 cm)SOC、TN、C∶N、C∶P、N∶P均显著高于深层(>100 cm)。克里格空间插值结果表明,研究区表层土壤中SOC、TN、TP含量具有东高西低的特征,而C∶N、C∶P、N∶P具有低值区集中于东部、高值区散布在西部的空间分布格局。成土母质和土壤类型等自然因素严重制约了研究区土壤碳氮磷的空间变异,同时土地利用变化等人为因素也起到了不可忽视的作用。   相似文献   

14.
Experimental study of enhanced in-situ micro-ecological remediation of petroleum contaminated loess soil was carried out in Zhongyuan oil production areas, and the enhanced in-situ micro-ecological remediation technique includes optimistic in-situ microbial communities, physical chemistry methods, alfalfa planting and regulation of soil environmental elements. Experiments showed that the oil content in the contaminated soil with oil content about 2 898.25 mg/kg can be reduced about 98.61% after in-situ micro-ecological remediation for 99 days, which demonstrated the effectiveness of in-situ micro-ecological remediation methods for petroleum contaminated soil in central plains of China, and explored the practical and feasible application of these methods.  相似文献   

15.
Bioremediation is an effective measure in dealing with such contamination, particularly those from petroleum hydrocarbon sources. The effect of soil amendments on diesel fuel degradation in soil was studied. Diesel fuel was introduced into the soil at the concentration of 5 % (w/w) and mixed with three different organic wastes tea leaf, soy cake, and potato skin, for a period of 3 months. Within 84 days, 35 % oil loss was recorded in the unamended polluted soil while 88, 81 and 75 % oil loss were recorded in the soil amended with soy cake, potato skin and tea leaf, respectively. Diesel fuel utilizing bacteria counts were significantly high in all organic wastes amended treatments, ranging from 111 × 106 to 152 × 106 colony forming unit/gram of soil, as compared to the unamended control soil which gave 31 × 106 CFU/g. The diesel fuel utilizing bacteria isolated from the oil-contaminated soil belongs to Bacillus licheniformis, Ochrobactrum tritici and Staphylococcus sp. Oil-polluted soil amended with soy cake recorded the highest oil biodegradation with a net loss of 53 %, as compared to the other treatments. Dehydrogenase enzyme activity, which was assessed by 2,3,5-triphenyltetrazolium chloride technique, correlated significantly with the total petroleum hydrocarbons degradation and accumulation of CO2. First-order kinetic model revealed that soy cake was the best of the three organic wastes used, with biodegradation rate constant of 0.148 day?1 and half life of 4.68 days. The results showed there is potential for soy cake, potato skin and tea leaf to enhance biodegradation of diesel in oil-contaminated soil.  相似文献   

16.
One of the environmental concerns in recent decades is the prevalence of different pollutants in soil. Hence, the importance of remediation has led to the development of various methods to remediate polluted soil. Among these methods, soil washing has gained significant attention to treat polluted soils. In this paper, the response surface methodology was applied in order to determine the optimal conditions for total petroleum hydrocarbon remediation using nonionic surfactant Brij35 in soil environment. The effect of different factors in soil washing process including surfactant solution concentration and volume, washing time, age of pollution and frequency of washing are evaluated. The predicted values for total petroleum hydrocarbon remediation efficiency by the response functions are in a very close agreement with experimental data (R-2= 98.75 %). The second order model was developed as experimented response and optimal conditions were obtained by analyzing the contour and surface plots and also by solving the regression equation using LINGO 9.0 software. The optimal concentrations (8 g/L), volume of surfactant solution (500 mL), washing time (75 min), age of pollution (29 days) and frequency of washing (three times) are determined. In this optimal condition, the removal efficiency has been observed to be 93.54 % which conforms to the results of process optimization using response surface methodology. Based on the results, it can be concluded that the response surface methodology is a suitable approach to determine the optimal conditions of soil washing to remediate organic hydrophobic pollutants using the nonionic surfactant Brij35 from the soil.  相似文献   

17.
郭永丽  章程  吴庆  全洗强 《地球科学》2021,46(6):2258-2266
石油类有机物污染是地下水环境领域亟须解决的关键课题.本次研究耦合数值模拟和水文地球化学技术模拟岩溶裂隙含水层中石油类有机物的自然衰减过程并定量计算其自然衰减机制.基于BIOSCREEN模型的模拟计算可知,近30年对流、弥散、稀释等物理过程和生物降解过程对石油类有机物衰减贡献率的平均值分别为31.53%和68.47%,生物降解作用是岩溶裂隙含水层自然修复能力的主要机制.利用质量守恒定律分析水化学(HCO3-、NO3-)和同位素(δ15NNO3、δ18ONO3和δ13CDIC)之间的相关关系可知石油类有机物生物降解贡献地下水HCO3-的平均值为33.93%;石油类有机物生物降解消耗主要电子受体NO3-贡献地下水δ13CDIC的百分率为30.77%且其占总生物降解的90.69%.   相似文献   

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