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1.
芽孢杆菌DQ02吸附摄取、运输和降解正十六烷的机理研究   总被引:1,自引:0,他引:1  
使用大庆油田石油污染土壤中分离出的优势菌种(芽孢杆菌DQ02),研究其对正十六烷吸附摄取、运输和降解的机理.结果表明,芽孢杆菌DQ02细胞可能与比其小得多的被溶解、似溶解的烷烃颗粒作用,也可能会与比细胞大的烷烃颗粒直接接触这种方式摄取正十六烷,并且DQ02对正十六烷的吸附过程为快速表面吸附过程.芽孢杆菌DQ02运输正十...  相似文献   

2.
鼠李糖脂对微生物菌剂降解石油的影响   总被引:2,自引:0,他引:2  
以石油烃降解微生物菌剂和铜绿假单胞菌株A6为对象,考察不同浓度鼠李糖脂对菌剂细胞表面疏水性、原油降解性能和微生物生长的影响,采用GC-MS分析石油中正构烷烃组分的降解情况。结果表明,低浓度鼠李糖脂就可提高菌剂细胞的表面疏水性和原油降解效果。以250mg/L添加组最明显,第7天疏水性达最高,为58.6%,比对照组提高约26.2%;降解第15天原油降解率达71.6%,分别比对照组和TW20组提高16%和13.3%。GC-MS结果显示鼠李糖脂对高碳数烷烃的降解作用大于低碳数烷烃,正二十三烷和正三十三烷的降解率分别较对照提高了21.5%和33.7%。菌剂对奇数碳烷烃的降解效果优于偶数碳烷烃。鼠李糖脂分别使菌剂中细菌、放线菌和霉菌的最大生物量提高了5.7、2.4和1.8倍。鼠李糖脂对微生物细胞疏水性和生物量的提高与石油降解效果正相关。  相似文献   

3.
从胶洲湾P3-1站位采集的石油污染海洋底泥中筛选得到一株能以原油为唯一碳源生长良好的石油烃降解菌株JZ3-21。经过形态、生理生化特征试验和16S rDNA序列分析结果,鉴定JZ3-21为恶臭假单胞菌属(Pseudomonas puti-da);实验研究了该菌株对5种石油烃模式物(正十六烷、甲苯、萘、芘和邻苯二酚)的降...  相似文献   

4.
苯酚的厌氧生物处理   总被引:3,自引:0,他引:3  
采用不断增加苯酚浓度而降低葡萄糖浓度的方法可驯化厌氧污泥中的微生物,使厌氧污泥最终以苯酚为唯一碳源生长,可显著提高厌氧污泥降解苯酚的能力;对苯酚间歇厌氧降解过程进行了分析。苯酚浓度在0~1.680 mg/L范围内,其厌氧降解过程符合一级动力学。Aiba模型、Haldane模型和Teisser 模型均可很好地描述处于对数期时厌氧污泥的比生长速率与初始底物浓度之间的关系,其中以Teisser 模型模拟的效果最好。将驯化污泥接种于UASB中可实现对含酚废水处理的连续运行,最大的有机负荷达2 g COD/(L·d),稳定运行时苯酚的去除率可维持在96%以上。  相似文献   

5.
近年来,石油污染造成的环境问题日益严重,寻找高效的石油降解菌株成为石油污染微生物修复的关键因素。通过对炼油废水中筛选出的一株高效降解石油烃菌株L4进行菌株形态特征观察、生理生化特性实验以及16SrDNA序列分析,鉴定其为苍白杆菌(Ochrobactrum ciceri)。并对L4降解石油烃效果、降解动力学及降解过程中的菌体浓度变化进行了研究,结果表明:在初始质量浓度为4 000mg/L的石油烃中加入该菌株,120r/min、30℃下振荡培养6d后,石油烃降解率高达98.98%。L4降解石油烃的动力学曲线与零级动力学方程拟合效果良好,半衰期为2.3d。L4在降解石油烃的0~1d,菌体生长较为迟缓,随后进入对数生长期;4d后,生长速率逐渐降低直至为零,石油烃降解率也缓慢增加,直至趋于稳定。  相似文献   

6.
采用化学共沉淀法合成磁性海泡石,通过静态吸附实验研究磁性海泡石对Cr(Ⅵ)的吸附特性及其动力学。结果表明,磁性海泡石对Cr(Ⅵ)的吸附在90 min内即可达到平衡;体系的初始pH是影响磁性海泡石吸附Cr(Ⅵ)性能的重要因素;当废水中Cr(Ⅵ)的初始浓度为50 mg/L时,磁性海泡石的适宜投加量为10 g/L;随反应温度的升高,磁性海泡石对Cr(Ⅵ)的吸附量增加;温度为25、35和45℃时,磁性海泡石对Cr(Ⅵ)的饱和吸附量分别为3.32、3.72、4.08 mg/g;吸附动力学曲线可以用拟二级反应动力学模型拟合;内扩散和液膜扩散联合控制Cr(Ⅵ)在磁性海泡石上的吸附过程,其中内扩散的控速作用大于液膜扩散。  相似文献   

7.
污泥衍生吸附剂对铅离子的吸附机理研究   总被引:4,自引:0,他引:4  
研究了化学活化法热解制取污泥衍生吸附剂的工艺过程,得出相应工艺条件。利用污泥衍生吸附剂吸附溶液中重金属离子Pb^2+,得到动力学模型。实验结果表明:(1)该吸附过程分为3个阶段:初始阶段(t≤20min)、过渡阶段(20min〈t≤30min)和后期阶段(t〉30min),满足线性方程dC/dt=kC;(2)该吸附过程的吸附活化能E=26,5kJ/mol,吸附频率因子A=6900s^-1。整个吸附过程为扩散吸附,吸附传质速度由孔隙扩散阶段和内表面吸附共同控制。  相似文献   

8.
采用阳极氧化法制备Ru—TiO2光电极,以该电极为工作电极,石墨作对电极,饱和甘汞电极为参比电极,对亚甲基蓝溶液的光电催化降解进行了研究。结果表明:煅烧温度600oC,掺杂1%Ru的Ru-TiO2光电极催化活性最好;以紫外灯(125W)为光源,当外加偏压0.2V,pH为5时,Ru-TiO2光电催化亚甲基蓝120min可使其完全脱色;亚甲基蓝的光电催化降解遵从Langmuir—Hinshelwood动力学模型,测得其反应速率常数k:0.781mmol/(L·min),吸附常数K=0.225L/mmol。  相似文献   

9.
新型立体浮床处理河道微污染源水的挂膜特性   总被引:1,自引:0,他引:1  
立体浮床是一种新型的生物预处理方法。采用了"曝气充氧+新型立体浮床"强化处理方法治理微污染河水,对立体浮床挂膜期间底部填料上的生物膜特性及微污染河水处理效果进行了实验研究。结果表明,在河道水温为15.2~23.6℃,pH在7.0~7.8,溶解氧浓度为4.0~5.9 mg/L时,经40 d左右时填料挂膜成熟。通过对水质和微生物指标分析,填料挂膜分为4阶段:物理吸附阶段—物理吸附-生物繁殖阶段—生物强化吸附降解阶段—挂膜成熟阶段。填料挂膜成熟后,污染物去除效果良好,浊度、COD和NH3-N的去除率分别达到了20.1%、17.5%和18.3%。  相似文献   

10.
利用苯酚诱导获得厌氧菌群JAC1强化去除土壤中的石油烃,对其在厌氧条件下的石油烃降解条件进行了优化,得到最适降解条件为:pH 7.5~8.5,土壤总石油烃(TPH)质量浓度50 mg/kg, NaCl质量分数0.3%,JAC1接菌量0.15 mL/g。厌氧菌群JAC1对石油烃的降解符合一级动力学模型。通过气相色谱质谱联用仪分析,芳香烃较直链烷烃更难降解,推测部分长链烷烃在降解过程中会分解为短链烷烃后再进行降解。基于土壤宏基因组测序分析可知,土壤微生物群落多样性与TPH浓度呈负相关,投加JAC1后土壤中与石油烃降解有关的功能菌群相对丰度呈现出不同程度增高,说明JAC1有助于建立一个高效的微生物降解体系来强化石油烃降解。  相似文献   

11.
Maki H  Sasaki T  Harayama S 《Chemosphere》2001,44(5):1145-1151
We investigated the physicochemical changes resulting from irradiation by sunlight of biodegraded crude oil. An Arabian light crude oil sample was first subjected to microbial degradation. n-Alkanes and aromatic compounds such as naphthalenes, fluorenes, dibenzothiophenes and phenanthrenes possessing short, alkyl side chain(s) were almost completely degraded, while the contents of the saturated and aromatic fractions were reduced by 70% and 40%, respectively. This biodegraded oil was then suspended in seawater and exposed to sunlight irradiation for several weeks. The most remarkable change caused by the irradiation was a substantial decline in the aromatic fraction with a concomitant increase in the resin and asphaltene fractions. A 13C-nuclear magnetic resonance (NMR) spectroscopic analysis showed that the aromaticity of the biodegraded oil was significantly lower in the irradiated sample. A field desorption-mass spectrometric (FD-MS) analysis showed that sunlight irradiation reduced the average molecular weight of the oil components and formed oxygenated compounds. Consistent with this observation is that the oxygen content in the oil increased as the irradiation was prolonged. The bioavailability of the biodegraded oil was increased by the photo-oxidation: the growth of seawater microbes was minimal when the non-irradiated biodegraded oil was used as the source of carbon and energy; however, growth was significant when irradiated biodegraded oil was used. The concentration of dissolved organic carbon (DOC) increased linearly during the sunlight irradiation of the biodegraded oil, and this increase was matched by an increase in ultraviolet-absorptive materials in the seawater. The photochemically formed, water-soluble fraction (WSF) showed acute toxicity against the halophilic crustacean, Artemia.  相似文献   

12.

In this experimental study, the feasibility of using the oil obtained from waste fishing net as a substitute for diesel fuel was investigated. Waste fishing net oil (WFNO) was obtained through pyrolysis process on a laboratory scale setup and used as a fuel in diesel engine. The properties of oil obtained from waste fishing net were examined and compared with conventional diesel fuel. Results indicated that the WFNO possesses excellent fuel properties. The calorific value of WFNO is 44,450 kJ/kg, which is higher than diesel by 1.48%. In order to study the possibility of using WFNO and its blends (WFNO 25%, WFNO 50%, WFNO 75% and WFNO 100%) with diesel as a fuel, an experimental investigation was carried out on a single-cylinder, four-stroke diesel engine. Experimental results proved that WFNO works satisfactorily on a diesel engine without any engine modifications. Brake thermal efficiency was decreased and brake-specific fuel consumption was increased while using WFNO and its blends. Moreover, there was a slight increase in engine emissions like CO, UHC, NO with WFNO and its blends.

  相似文献   

13.
以润滑油废白土为原料,利用电热解法,研究了热解终温、加热速率和CaO添加量对热解产物的影响。实验结果表明:热解终温对热解产物的影响最为显著。随着热解终温的升高,不凝气产量和产油率均迅速增加。当热解终温达到600℃时,其增加的速率逐渐缓慢增大。当控制热解终温为800℃、加热速率为16℃/min、CaO添加量为0.5%时,富氢气体产量为189.2 L/kg,气体中主要成分为H2和CH4,其含量分别为27.97%和41.64%;热解残渣含油率和重金属溶出物均低于标准规定值,热解油产率为10.98%,回收率为38.94%,其主要成分为汽油、柴油和重油3部分组成,分别含19.13%、31.35%和49.52%。  相似文献   

14.
Background, Goal and Scope Cleaner CRYSTAL Simple Green (SG) was used for the cleanup of the oil spill in the Baltic Sea near Lithuania in 2001. No scientific data are available on the effects and consequences of its application for local aquatic life. The aim of this study was to determine and compare sublethal effects of a) solution SG; b) crude oil alone; c) SG in combination with oil on rainbow trout Oncorhynchus mykiss at different stages of its development in laboratory conditions.Methods Laboratory studies were performed on adult rainbow trout (4-day duration) and on yolk-sac larvae (25-day duration) evaluating their biological parameters. Concentrations of water-soluble and thin-dispersed fractions of petroleum hydrocarbons were measured using gas chromatography.Results and Discussion SG solution (0.5 mg/l) did not affect the survival of larvae and adult fish, and no significant changes were determined in respiratory parameters of the exposed larvae and adult fish. The most expressed alterations were found in morphological parameters (a decrease in the average body mass) of larvae and in haematological indices (a decrease in the leukocyte count) of adult fish at the end of the tests. Crude oil (1610 mg/l) did not affect the survival of adult fish during the 4-day exposure. An increase in larvae mortality rate (~ 36%) was recorded at the end of the tests. A significant decrease in the average body mass and heart rate of larvae as well as in gill ventilation frequency of larvae and adult fish were determined. SG combined with oil induced an increase in larval mortality  46% of individuals died at the end of the tests. No mortality was recorded in adult fish. The average body mass and heart rate of larvae were significantly decreased. Marked changes were also found in respiratory parameters (gill ventilation frequency of larvae and adult fish significantly decreased, while “coughing” rate increased). A 1-day, 2-day exposure of fish to SG combined with oil induced a significant decrease in the leukocyte count of adult fish, which was also determined at the end of the tests. The augmentation of adverse impact could be explained by the data obtained from our studies. When SG was added into dilution water with crude oil the concentration of petroleum hydrocarbons in the mixture increased 3 ~ 4.5 times after 24 h and 96 h, respectively. Conclusions The comparative study of the effects of crude oil alone, SG and SG combined with oil showed that their toxic effects on fish differed. Oil combined with SG was found to be more toxic to fish (larvae and adults) than SG alone and oil alone. Fish at early stages of development (yolk-sac larvae) were more sensitive to the effects of the compounds studied than adults.Recommendations and Outlook To diminish the negative impact of oil spill cleanup using chemicals on aquatic ecosystems, it is recommended to carry out more comprehensive studies of their effects and after-effects in laboratory conditions using a wide scale of local aquatic organisms. The selected species of the most sensitive aquatic organisms should include those which are unable to escape the impact of combined action of oil and cleaners. Special attention should be directed to the research of effects of these pollutants on studied organisms at their most sensitive stages of life (reproduction, hatching, early stages of development), as after-effects of exposure to pollutants may be observed in future generations.  相似文献   

15.
微生物法治理油污土壤具有成本低、效果好的特点 ,其原理是微生物利用油烃作为碳源合成自身物质 ,进行生长繁殖 ,从而使油烃的含量得到减少。而与此同时 ,微生物的数量也会发生相应的变化。目前油污土壤微生物的研究主要局限于对污染土壤中分离提纯的单一菌种的降解效能的研究。本文对土著油污土壤微生物在适宜条件下的数量和种类变化进行了实验分析 ,并对油烃的化学组成作了初步探讨。分离出 4株对石油具有耐受性和降解能力的微生物。结果表明 ,在 4株微生物数量都增加的时候 ,石油烃的降解速度最快。  相似文献   

16.
通过焉耆盆地石油开发区石油污染物水环境污染途径特点的分析 ,认为落地油将通过风蚀作用由大气传输以降尘的形式落入水体 ,对水环境产生影响。本文以土壤侵蚀的风洞实验求得污染源源强 ,采用高斯模式对地表风蚀作用的传输量进行估算 ,进而对石油开发区落地油通过大气传输途径对区域水环境 (博斯腾湖 )的影响进行了预测 ,建立了相应的模型。为人们了解干旱区石油污染物风蚀作用水环境污染影响提供了初步依据 ,对干旱区湖泊石油污染的全面防治提供了科学范式  相似文献   

17.
Using the 2010 Deepwater Horizon oil spill in the Gulf of Mexico as an impetus, we explored the potential for TiO2-mediated photocatalytic reactive oxygen species (ROS) generation to increase the bioavailability (solubility) and biodegradability of weathered oil after a spill. Food grade TiO2, which is FDA approved for use as food additive in the United States, was tested as a photocatalyst for this novel application. Photocatalytic pre-treatment (0.05 wt.% TiO2, UV irradiation 18 W m?2, 350–400 nm) for 24 h in a bench top photoreactor increased the soluble organic carbon content of weathered oil by 60%, and enhanced its subsequent biodegradation (measured as O2 consumption in a respirometer) by 37%. Photocatalytic pre-treatment was also tested outdoors under sunlight illumination, but no significant increase in solubility or biodegradation was observed after 11 d of exposure. Although sunlight irradiation of food-grade TiO2 generated ROS (assessed by the degradation of 4-chlorophenol as a probe compound), the efficacy of weathered oil pre-treatment was apparently hindered by sinking of the photocatalysts under quiescent conditions and illumination occlusion by the oil. Overall, results indicate that photocatalytic pre-treatment to stimulate bioremediation of weathered oil deserves further consideration, but controlling the buoyancy and surface hydrophobicity of the photocatalysts will be important for future efforts to enable ROS generation in proximity to the target compounds.  相似文献   

18.
The present research was intended to determine the suitability of the CALUX assay as a screening method for dioxins in fish oil used as a feed ingredient in Japan. Alteration of TEQ in fish oil according to newly proposed toxic equivalency factors (TEF) is also discussed. In the analysis, polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in 41 fish oil samples were determined by using high-resolution gas chromatography/high-resolution mass spectrometry (HRGC/HRMS) and CALUX bioassay. The mean TEQ values derived from 1998 WHO-TEF of PCDD/Fs and DL-PCBs were 2.6 and 9.9 pg g(-1) (ww), respectively. The levels of TEQ derived from the recently re-evaluated 2005 WHO-TEF were slightly lower than those of the former in both groups. Notably, the contribution of mono-ortho DL-PCBs to total 2005 WHO-TEQ was considerably decreased compared to the case of 1998 WHO-TEQ, resulting from the reduction in its TEF values, while the non-ortho DL-PCBs contribution was increased. The mean TEQ determined by CALUX assay for PCDD/Fs was approximately three times higher, whereas DL-PCBs was approximately two times lower than WHO-TEQ determined by HRGC/HRMS; the sum of PCDD/Fs and DL-PCBs was very similar by both methods. The correlation coefficients of TEQ between the CALUX assay and HRGC/HRMS analysis were 0.84, 0.89, and 0.90 for PCDD/Fs, DL-PCBs, and the sum, respectively. These results suggest that the CALUX assay is a very useful method for the screening of dioxin-related compounds in fish oils.  相似文献   

19.
固定化原油降解菌的制备及其性能研究   总被引:2,自引:0,他引:2  
从石油污染土壤中筛选出的石油降解菌Y-13对石油的降解率为57.45%,经初步鉴定为芽孢杆菌属,以Y-13为固定化对象,选择聚乙烯醇(PVA)、海藻酸钠(SA)为主要载体材料,以胜利原油为反应底物,研究了固定化微球的制备和运行条件对微球性能的影响,实验确定了PVA-H3BO3包埋法制备固定化微球的最佳条件,最高降解率为79.04%;对PVA-H3BO3微球的性能测定结果表明:这种固定化微球具有良好的机械强度、弹性和渗透性、较高的比表面积和孔容;固定化微球比游离细菌对外界的适应性要强,适宜pH值、接种量和活化时间分别为7.5、1∶10和21 h。  相似文献   

20.
油脂废水是一种重要的水污染源。研究了表面活性剂和H2O2对洋葱伯克霍尔德氏菌(Burkholderia cepacia)降解油脂的影响。结果表明:适量的表面活性剂和H2O2促进油脂的降解。表面活性剂可以增强油脂在水相中的溶解度,提高油脂在水中的乳化程度从而增加其生物可利用性。当Tween-80浓度600mg/L时,油脂降解率达到91%。低浓度H2O2不仅能刺激微生物生长,而且使培养液中的pH值保持相对稳定,提高了微生物对油脂的降解率。H2O2在浓度为400mg/L时,能使油脂降解率达到90%。  相似文献   

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