微生物处理含油废水的实验研究

实验以天津大港油田受原油污染的土壤为菌源,原油为唯一碳源,采用限制性底物大剂量冲击驯化方式,共驯化、筛选分离出四株对原油有一定降解能力的优势微生物,初步认定为假单胞菌属(Pseudomonas);以此优势菌株为始发菌株,聚乙烯醇为载体,采用包埋法进行微生物固定化实验,实验结果表明:微生物固定化后微生物的活性相对稳定,可以认为聚乙烯醇是一种比较好的包埋载体。     

莲藕状固定化真菌(镰刀菌)对土壤中菲、芘的降解

采用莲藕状聚乙烯醇复合载体对镰刀菌(Fusarium sp.)固定化包埋,分别进行了不同接种量的固定化真菌对菲、芘的降解,固定化真菌对不同系列浓度菲、芘的降解试验,以及对固定化真菌在自然土壤中对菲、芘降解的各项参数作了测定,结果表明,固定化真菌具有较好的降解效果,同时用电镜观察研究了镰刀菌在固定化载体中的分布形态.自然土壤中固定化真菌在360h时,对菲、芘的降解效率分别为76.96%和20.69%,而土著菌仅达到33.37%和15.28%.     

菌糠强化微生物降解石油污染土壤修复研究

采用菌糠协同高效石油烃降解菌Microbacterium.sp.Q2进行石油污染土壤修复试验研究,分别设置菌糠固定化微生物组（SIM）、菌糠-游离菌组（SMSB）、菌糠单独组（SMS）和对照组（CK）4组修复实验.考察不同处理方式下对石油污染土壤微生物数量、酶活性和石油烃降解效果的差异性并确定石油污染土壤的最佳修复方案.结果表明：不同修复方式下,SIM组的土壤呼吸强度、微生物数量及酶活性较其他组有明显提高,其对石油烃去除率分别比其他3组提高11.84%、22.15%、54.09%.土壤中脱氢酶活性以及微生物活性与石油烃降解率的相关性显著,此外菌糠固定化微生物对石油污染土壤修复具有生物强化和生物刺激协同的作用机制.     

腐植酸改性生物质电厂灰固定化微生物修复石油烃污染土壤

以生物质电厂灰为载体,用腐植酸对其改性后,负载石油烃降解菌形成固定化菌剂对原油污染土壤进行修复,其中对生物质电厂灰改性的最佳条件以及固定化菌剂对原油污染土壤的修复效果进行了考察。结果表明:生物质电厂灰改性的最佳条件为:电厂灰粒径10~40目,固液比1∶1,改性时间4 h,改性后孔状结构增多且表面粗糙,有利于微生物的附着,固定的微生物数量可达1.5×109 CFU/g。进行60 d的修复后,固定化菌剂对污染土壤中石油烃的降解率达到51.9%,比游离菌提高了25.0%,对长链正构烷烃、芳香烃及胶质的降解率分别提高了9.6%、31.7%和37.5%。固定化生物质电厂灰的应用使石油烃降解菌得到保护和支撑,提高了土壤基础呼吸速率和土壤酶活性,实现了石油烃的高效降解。因此,腐植酸改性生物质电厂灰是一种在石油污染土壤修复方面具有应用潜力的微生物固定化材料。     

芽孢杆菌H-1菌株的固定化及降解动力学研究

采用海藻酸钠-海藻酸钙法对芽孢杆菌H-1菌株进行包埋实验,测试各固定化因素对凝胶微球物理性能的影响,得到各因素合适的取值范围。以石油降解率为试验指标对固定化因素进行4因素3水平正交试验,结果显示菌株的最佳固定化条件为海藻酸钠浓度7%、菌悬液添加量75%、CaCl2浓度2%、交联时间24 h。对比固定化菌株与游离菌株的降解效果,结果显示固定化菌株的降解效率大于游离菌株。对固定化菌株的降解动力学进行研究,结果表明当石油浓度较低时,固定化菌株的降解动力学方程符合Monod方程的线性简化形式,方程的半饱和常数K S=52.33 mg/L,最大反应速率v max=44.05 d-1。当原油浓度较高时,其降解速率大于方程的v max。     

海洋石油降解菌Alcanivorax sp. 97CO-5的固定化及其石油降解效果

本文应用不同材料固定海洋石油烃降解菌Alcanivorax sp.97CO-5,考察并比较了其成型、传质、包埋菌体活性和石油降解性能。实验结果表明:2.5%海藻酸钠包埋材料中细菌的增长最为显著,8 d后材料中细菌数量达到1.2×106CFU/g,为初始细菌细胞数量的3.85倍,是最适的固定化材料。固定化菌剂的石油降解实验结果表明,固定化菌剂14 d对石油的净降解率达到34.1%,其石油降解效果优于游离菌体(28.3%);气相色谱质谱联用分析表明,固定化菌剂对石油中总烷烃降解率为57.9%,其中对nC21~nC31的中长链烷烃的降解率可达到54.6%;固定化菌剂相对于游离菌体,对芴(FLU)和二苯并噻吩(DBT)两类烷基化多环芳烃的降解率明显提高,达到44.9%和44.2%,而游离降解菌仅为25.4%和24.7%。实验证明,固定化技术促进了Alcanivorax sp.97CO-5菌体降解性能的发挥尤其是对中长链烷烃和部分芳烃成分的降解。     

海藻酸钠包埋固定化微生物处理含油废水研究

采用海藻酸钠固定化包埋活性炭与菌Brevibacillus parabrevis Bbai-1,制备海藻酸钠-活性炭固定化微球。通过活性炭吸附前后的菌浓变化,测定了25℃时活性炭对Bbai-1的最大吸附量。采用正交试验优化了影响海藻酸钠-活性炭固定化微球的物理性质和微生物活性的4个主要因素(海藻酸钠浓度,活性炭含量,种子菌液浓度和交联时间),确定了固定化微球的最佳制备条件:海藻酸钠浓度为3.5%,活性炭含量为0.7%,种子菌液浓度为6×107 cell/mL,交联时间为24 h。并在25℃,原油含量为0.2%,固定化微球与含油培养基的体积比为3:20时,以游离菌作对比,考察了固定化微球降解原油的最佳pH和盐度。结果表明,固定化菌在pH 6~9,盐度为1.5%~3.5%时,原油降解率可达50%以上,比游离菌提高了20%,且具有较高的盐度适应能力和较宽的pH适应范围。     

一种耐酚菌种及其固定化细胞降解含酚废水性能的比较研究

通过对土壤及污水的采样、分离、纯化,得到了一种降解苯酚的菌种,经过一系列驯化实验,使其苯酚耐受能力达915 mg/L。在此基础上,利用正交实验,确定了该菌种固定化细胞制备的最优操作条件。之后,对游离细胞和固定化细胞的降解苯酚过程进行了动力学分析与比较。结果表明,2种类型细胞的降解苯酚过程均符合Monod模型,并且固定化细胞的降解效果明显高于游离细胞。      

改性竹炭固定化威尼斯不动杆菌吸附协同降解柴油废水的机理及动力学分析

利用改性竹炭作为载体来固定化威尼斯不动杆菌(Acinetobacter venetianus),用于去除柴油.结果显示,培养96 h后,固定化菌对柴油的去除率为86.35%,要高于游离菌(80.50%).为了探究固定化菌去除柴油的机理,采用动力学拟合实验数据,发现固定化菌去除(吸附-降解)柴油中总石油烃(TPHs)的过程符合伪二级动力学,表明TPHs是先吸附在改性竹炭上,然后被目标菌降解.为了进一步证实,利用扫描电镜(SEM)观察到Acinetobacter venetianus很好地固定在载体材料上.傅里叶红外光谱(FTIR)结果表明,经固定化菌处理后,柴油水溶液的谱图在3437.2、2924.4、1407.8 cm-1处出现新的吸收峰,可能为烷烃降解的酯类及羧酸类物质.GC-MS分析表明,相比游离菌,固定化菌对柴油的去除更为彻底.因此,改性竹炭不仅可以作为良好的固定化载体,同时因其对TPHs良好的吸附性能从而提高了去除效率,为油类污染中TPHs的生物材料修复提供了一个新的视角.     

低残油土壤中高效降油菌的筛选分离及其营养平衡

为了更有效地修复被石油污染的土壤,以低残油土壤为菌源,原油为唯一碳源,经反复驯化筛选后得到降解石油的高效菌,初步鉴定其为动胶菌属(Zoogloeasp.)。并对该菌种的营养平衡条件进行了初探。试验筛选出优势氮源为NH4NO3,氮磷比应控制在4∶1左右。     

退役井场老化油污土壤的生物强化修复技术

退役井场油污土壤含油量低、原油重质化严重,为恢复其土壤属性,探索原位生物强化修复技术。在分析油污土壤中原油性质和土著菌群结构的基础上,优选配伍好的外源嗜烃菌,并应用生物促进剂,以及将菌剂固定化以提升其抗环境冲击能力,提升现场生物修复效率。结果表明:井场油污土壤平均含油率为14.6 mg/g,重质组分含量达到57%,土著菌群结构中缺少降解重质组分的微生物。室内优选2株具有协同效应的重质组分降解菌,在生物促进剂用量为500 mg/L和以锯末固定外源菌条件下,降解达标时间由120 d缩减至80 d。现场开展了2700 m2场地原位修复试验,采用地耕法工艺,修复8个月后含油率由14.6 mg/g降至3.30 mg/g,达到GB 36600—2018《土壤环境质量建设用地土壤污染风险管控标准(试行)》建设用地Ⅱ类用地要求。优选的重质油降解菌剂能提升原油污染物的降解速率,通过促进剂和菌剂投加方式的优化,可有效缩短修复周期。     

海洋微生物降解石油的研究

从青岛近岩海水中分离、筛选到73株细菌和10株真菌，并对其降解石油的能力进行了研究，结果表明，多数菌具有明显的降解石油的能力，部分菌株对短链烷烃正已烷和芳香烃萘具有不同程度的降解能力，其中，有3个菌株对石油的生物降解率分别高达58.35％、62.75％、71.06％。     

分离海洋不动杆菌及其对石油烃降解性能研究

石油降解菌在石油污染生物修复技术中起到非常重要的作用。本研究分别以渤海湾油污区采集的水样,油样,水油泥混合样为材料富集分离石油降解菌,对其进行生理生化及分子生物学鉴定,并采用GC-MS测定烷烃、环烃、芳香烃等石油烃组分的变化。其中3株菌具有较高石油烃降解能力,16SrRNA序列分析表明该3株菌均与不动杆菌属（Acinetobacter）有99%序列相似性,可初步鉴定为不动杆菌属（Acinetobacter）。3株菌的石油烃降解能力依次为Tust-DM21＞Tust-DC12＞Tust-DW04,对原油成分的降解效果依次为烷烃＞芳香烃＞环烃。其中菌株Tust-DM21为一株高效石油烃降解菌,28℃于富集培养基培养10 d后,对烷烃（C10~C30）的降解率可达98%,对芳香烃和环烃的降解率达88%。研究表明,Tust-DM21菌株对烷烃,环烃,芳香烃都有较强的降解能力,是一株具有较好开发前景的石油降解菌。     

Efficient degradation of lube oil by a mixed bacterial consortium

A laboratory study was performed to assess the biodegradation of lube oil in bio-reactor with 304# stainless steel as a biofilm carrier. Among 164 oil degrading bacterial cultures isolated from oil contaminated soil samples, Commaonas acidovorans Px1, Bacillus sp. Px2, Pseudomonas sp. Px3 were selected to prepare a mixed consortium for the study based on the efficiency of lube oil utilization. The percentage of oil degraded by the mixed bacterial consortium decreased slightly from 99% to 97.2% as the concentration of lube oil was increased from 2000 to 10,000 mg/L. The degradation of TDOC (total dissolved organic carbon) showed a similar tendency compared with lube oil removal, which indicated that the intermediates in degradation process hardly accumulated. Selected mixed bacterial consortium showed their edge compared to activated sludge. Scanning electron microscopy (SEM) photos showed that biofilms on stainless steel were robust and with a dimensional framework constructed by EPS (extracellular polymeric substances), which could promote the biodegradation of hydrocarbons. The increase of biofilm followed first-order kinetics with rate of 0.216 μg glucose/(cm2·day) in logarithm phase. With analysis of Fourier transform infrared spectroscopy (FT-IR) and gas chromatography-mass spectrometry (GC-MS) combined with removal of lube oil and TDOC, mixed bacterial consortium could degrade benzene and its derivatives, aromatic ring organic matters with a percentage over 97%.     

油田区土壤石油烃组分残留特性研究

为了揭示石油开采区土壤石油烃组成及残留特性,探讨石油污染物的来源与风化程度,采集了胜利油田孤岛和河口采油区共5口油井周边土壤样品及原油样品,利用气相色谱-质谱联用仪(GC-MS)分析原油及土壤样品中的链烷烃(正烷烃+姥鲛烷+植烷)及多环芳烃(polycyclic aromatic hydrocarbons,PAHs)共51种石油烃单体的含量.结果表明,与原油相比,油田区土壤总提取物中链烷烃与PAHs所占的比例明显偏低;土壤石油烃的组分构成与原油相比,链烷烃中碳数小于12的正烷烃比例明显降低,而高碳数正烷烃比例增加.选择正十八烷/植烷作为指示土壤风化程度的标志,利用主成分分析(principal component analysis,PCA)法分析其与土壤中各石油烃组分的关系,结果显示碳数大于33的正烷烃与中环芳香烃具有高残留性.利用主成分分析综合分析用于土壤石油烃来源识别的4个指标,结果表明,土壤中的石油烃具有明显的原油"指纹".研究结果为油田土壤污染特性的认识提供了依据与基础.     

Effcient degradation of lube oil by a mixed bacterial consortium

A laboratory study was performed to assess the biodegradation of lube oil in bio-reactor with 304# stainless steel as a biofilm carrier. Among 164 oil degrading bacterial cultures isolated from oil contaminated soil samples, Commaonas acidovorans Px1, Bacillus sp. Px2, Pseudomonas sp. Px3 were selected to prepare a mixed consortium for the study based on the e ciency of lube oil utilization. The percentage of oil degraded by the mixed bacterial consortium decreased slightly from 99% to 97.2% as the concentration of lube oil was increased from 2000 to 10,000 mg/L. The degradation of TDOC (total dissolved organic carbon) showed a similar tendency compared with lube oil removal, which indicated that the intermediates in degradation process hardly accumulated. Selected mixed bacterial consortium showed their edge compared to activated sludge. Scanning electron microscopy (SEM) photos showed that biofilms on stainless steel were robust and with a dimensional framework constructed by EPS (extracellular polymeric substances), which could promote the biodegradation of hydrocarbons. The increase of biofilm followed first-order kinetics with rate of 0.216 g glucose/(cm2 day) in logarithm phase. With analysis of Fourier transform infrared spectroscopy (FT-IR) and gas chromatography-mass spectrometry (GC-MS) combined with removal of lube oil and TDOC, mixed bacterial consortium could degrade benzene and its derivatives, aromatic ring organic matters with a percentage over 97%.     

Efficient degradation of lube off by a mixed bacterial consortium

A laboratory study was performed to assess the biodegradation of lube oil in bio-reactor with 304# stainless steel as a biofilm carrier.Among 164 oil degrading bacterial cultures isolated from oil contaminated soil samples, Commaonas acidovorans Pxl, Bacillus sp.Px2, Pseudomonas sp. Px3 were selected to prepare a mixed consortium for the study based on the efficiency of lube oil utilization.The percentage of oil degraded by the mixed bacterial consortium decreased slightly from 99% to 97.2% as the concentration of lube oil was increased from 2000 to 10,000 mg/L. The degradation of TDOC (total dissolved organic carbon) showed a similar tendency compared with lube oil removal, which indicated that the intermediates in degradation process hardly accumulated. Selected mixed bacterial consortium showed their edge compared to activated sludge. Scanning electron microscopy (SEM) photos showed that biofilms on stainless steel were robust and with a dimensional framework constructed by EPS (extracellular polymeric substances),which could promote the biodegradation of hydrocarbons. The increase of biofilm followed first-order kinetics with rate of 0.216 μg glucose/(cm~2·day) in logarithm phase. With analysis of Fourier transform infrared spectroscopy (FT-IR) and gas chromatography-mass spectrometry (GC-MS) combined with removal of lube oil and TDOC, mixed bacterial consortium could degrade benzene and its derivatives, aromatic ring organic matters with a percentage over 97%.     

石油降解低温细菌的筛选及降解特性的表征

从石油污染土壤中,通过低温富集,筛选并鉴定得到7株低温石油降解细菌。基于菌株降解石油组分特性,构建6组低温石油降解菌群,利用5 L发酵罐,并通过尾气分析仪在线监测菌群石油降解过程中的CO₂产生和O₂消耗变化,评价菌群的石油降解能力。由Arthrobacter sp. JLH 001,Acinetobacter baumannii JLH 002,Pseudomonas fragi JLH 003和Arthrobacter sp. JLH 006组成的菌群降解石油效果最佳,48 h后CO₂的产生值和O₂的消耗值达到最高,在15 ℃时、72 h后能完全降解1%的石油,并且在25 ℃时降解速度显著增强。结果表明:石油污染土壤的原位生物修复可通过低温石油降解菌群的添加实现高效及快速修复。     

Biodegradation of benzo[a]pyrene in soil by Mucor sp. SF06 and Bacillus sp. SB02 co-immobilized on vermiculite

Two indigenous microorganisms, Bacillus sp. SB02 and Mucor sp. SF06, capable of degrading polycyclic aromatic hydrocarbons （PAHs） were co-immobilized on vermiculite by physical adsorption and used to degrade benzo[a] pyrene （BaP）. The characteristics of BaP degradation by both free and co-immobilized microorganism were then investigated and compared. The removal rate using the immobilized bacterial-fungal mixed consortium was higher than that of the freely mobile mixed consortium. 95.3% of BaP was degraded using the co-immobilized system within 42 d, which was remarkably higher than the removal rate of that by the free strains. The optimal amount of inoculated co-immobilized system for BaP degradation was 2%. The immobilized bacterial-fungal mixed consortium also showed better water stability than the free strains. Kinetics of BaP biodegradation by co-immobilized SF06 and SB02 were also studied. The results demonstrated that BaP degradation could be well described by a zero-order reaction rate equation when the initial BaP concentration was in the range of 10--200 mg/kg. The scanning electronic microscope （SEM） analysis showed that the co-immobilized microstructure was suitable for the growth of SF06 and SB02. The mass transmission process of co-immobilized system in soil is discussed. The results demonstrate the potential for employing the bacterial-fungal mixed consortium, co-immobilized on vermiculite, for in situ bioremediation of BaP.