硫酸盐还原菌对油田的腐蚀状况及其微生物防控机理

介绍了硫酸盐还原菌（SRB）的特性、腐蚀现状、腐蚀机理、微生物防控机理,特别是反硝化菌竞争抑制治理硫酸盐还原菌造成危害的机理。     

硫酸盐还原菌的微生物腐蚀及其防护研究进展

综述了硫酸盐还原菌(SRB)引起微生物腐蚀(MIC)的各种机理及其形成生物膜的腐蚀作用,以及利用微生物防治硫酸盐还原菌腐蚀的研究进展.     

硫酸盐还原菌和异养硝化菌对304不锈钢腐蚀研究

研究了热电厂冷却塔黏泥中的硫酸盐还原菌和硝化菌的代谢特性。采用表面分析技术、腐蚀失重法、电化学技术分析304不锈钢在硫酸盐还原菌和硝化菌共同作用下的腐蚀行为。结果表明,混菌作用下304不锈钢表面形成均匀的生物膜,腐蚀速度小于单菌体系。     

金属材料的硫酸盐还原菌腐蚀研究进展

金属材料作为重要的机械工程材料，在应用过程中一直遭受着严重的腐蚀破坏。微生物腐蚀（MIC）是重要的金属材料腐蚀形式，其中以硫酸盐还原菌（SRB）引起的腐蚀最为严重。概述了几种典型金属在油气田、土壤和海水中的SRB腐蚀行为，着重阐述了金属材料SRB腐蚀机理的研究进展。     

石油生产中SRB腐蚀的危害与微生物防治途径

阐述了石油生产中由硫酸盐还原菌(SRB)引起的微生物腐蚀造成的巨大经济损失和安全隐患,总结了SRB腐蚀机理,重点介绍了阴极去极化机理和微生物防治方法.     

油田水中硫酸盐还原菌腐蚀控制技术

硫酸盐还原菌（简称SRB）广泛存在于油田生产的各个环节,其代谢过程中可产生硫化氢,进而损害设备、管线,造成巨大经济损失,硫化氢会污染环境,SRB代谢产物还会堵塞地层,影响采油生产。硫酸盐还原菌主要的危害是引发生产系统的腐蚀和污染。因此,本文主要探讨了油田水中硫酸盐还原菌腐蚀的控制技术,通过采用行之有效的控制技术对SRB的生长进行有效的防控,进而减少SRB的破坏力．促进采油工作的顺利进行。希望通过本文的探讨,能够为相关方面的研究提供理论性的参考。     

硫酸盐还原菌在8个土壤试验站中的分布规律研究

硫酸盐还原菌(SRB)是一种典型的腐蚀茵.对来自库尔勒、格尔木、拉萨、成都、大庆、沈阳、大港、鹰潭8个土壤试验站的表层土壤试样和2 m土壤试样进行了硫酸盐还原茵含量的检测,系统地分析了硫酸盐还原茵在不同土壤中的分布规律.结果表明,温度并不是决定SRB生长的唯一因素,SRB的生长状况与土壤类型关系密切.为微生物腐蚀的研究提供了依据.     

硫酸盐还原菌的变异及其对杀菌剂敏感性的研究

中原油田原油采出污水经“水质改性”后,硫酸盐还原菌出现变异现象。作者对SRB变异后的菌体形貌、腐蚀行为进行了初步研究,同时,评价了几种常用杀菌剂对变异SRB菌的杀灭效果,从而为有效防治SRB的腐蚀提供了理论依据。     

硫酸盐还原菌对20#钢腐蚀行为的影响

为了研究油气田现场生产工况下硫酸盐还原菌对20#钢腐蚀行为的影响,本文通过细菌培养实验、腐蚀失重实验等实验方法,利用激光共聚焦显微镜,扫描电镜等仪器,研究了矿化度、温度、H_2S、CO_2对硫酸盐还原菌(SRB)生长活性及对20#钢腐蚀行为的影响。结果表明:矿化度升高影响SRB细菌活性,SRB细菌导致的腐蚀行为减弱;温度变化对SRB细菌生长活性影响较大,高温下腐蚀主要由溶液自身环境造成;H_2S分压、CO_2分压对SRB细菌生长影响不大。     

硫酸盐还原菌的环境适应性研究

采用S培养基培养的方法对硫酸盐还原菌（一下简称“SRB”）进行了分离与鉴定。实验通过对SRB的生理性和生化特性的了解,结合其生存条件和存在状态进行研究,得出了主要的环境因素中pH值和温度对SRB活性的影响关系,并提出采用合适的环境因素来更好地控制SRB的生长代谢活动,以寻求有效的防治措施来控制硫酸盐还原菌引起的腐蚀,延长有关设备的正常使用寿命。     

反硝化抑制油田采出水中SRB的效果研究

以硫酸去除率及硫酸盐还原菌(sulfate reducing bacteria,SRB)的数量为指标,研究硝酸盐和反硝化细菌(denitrifying bacteria,DNB)对油田采出水中SRB的抑制作用。结果表明:在单独接种DNB (5%,体积分数)或投加硝酸盐浓度为100mg/L条件下,采出水中SRB的生长均受到有效抑制,其数量从104个/mL可降至10个/mL,硫酸盐去除率从25.5%分别降至6.8%和7.8%;当DNB (12.5%,体积分数)和硝酸盐(100mg/L)共同作用于采出水可使SRB的数量降至10个/mL以下,其硫酸盐去除率降至2.4%,两者对SRB的抑制作用具有协同作用。     

Mathematical model for a batch aerated submerged biofilm reactor for organic carbon and nitrogen removal

An aerated submerged biofilm (ASBF) pilot plant has been developed. The present study optimized an inexpensive method of enhanced wastewater treatment. Over a period of three and one half months, a total of 11 batch runs were performed. By the fourth run, the biofilm had matured to the point that it consumed all the ammonia in 40 hours. The investigation aimed to present mathematical models for describing the dynamic behaviors of the dissolved organic matter removal and nitrification in the Aerated Submerged Biofilm (ASBF) for a batch reactor. Based on the experimental data from the batch system of the ASBF pilot plant, mathematical models were developed to predict dissloved organic matter and ammonia nitrogen removal rates as a function of heterotrophic and autotrophic bacteria populations, dissolved organic matter concentrations, ammonia nitrogen concentrations, dissolved oxygen concentrations, and temperature. The mathematical models for dissolved organic matter and ammonia nitrogen removal in ASBF include two differential equations reflecting heterotrophic and autotrophic bacteria populations, and a number of kinetic parameters. Consequently, the results provide a better insight into the dynamic behaviors of heterotrophic and autotrophic biofilm growth and their practical application to wastewater for dissolved organic matter and ammonia nitrogen removal process.     

COD对反硝化抑制硫酸盐还原的影响

通过间歇试验探讨了COD对反硝化抑制硫酸盐还原系统的影响。结果表明,COD是反硝化抑制硫酸盐还原系统的一个重要因素,直接影响着系统中NO3-和SO42-的代谢以及S2-和NO2-的产生状况;当COD为120mg/L时,系统内碳源不足,存在着SRB和DNB对碳源的竞争,竞争中后者占优势,硫酸盐还原程度很小;当碳源充足时,由于受反硝化抑制,S2-呈现出先增加后减少再增加的变化趋势,分为碳源充足、反硝化控制和硫酸盐重新还原三个阶段,各阶段的作用时间随COD含量的不同而变化;系统中出现了不同程度的NO2-积累,其峰值和出现位置随COD不同而不同;NO2-是对SRB产生抑制的主要原因,当系统中NO2--N浓度大于2mg/L时,S2-产生呈下降趋势,SRB活性开始受到抑制。     

Velocity,subcooling and surface effects in the departure from nucleate boiling of organic binaries

The forced-convection loop at the University of Toronto was used to determine DNB heat fluxes for the full range of variation in composition of the binary systems acetone-toluene and benzene-toluene, over the velocity range 1.09-4.36 metre/sec. and the subcooling range 10-50°C. Special attention was given to the precise location of the DNB point relative to the maximum (critical) heat flux. The variation of the DNB heat flux with composition was found to be complex, but an empirical graphical correlation was obtained for each system, correlating DNB heal flux with composition, velocity and subcooling. A limited study of the effect of degree of surface roughness pointed towards an effect on DNB which varied with the degree of subcooling, but which was independent of the coolant velocity.     

Application of spent sulfidic caustics for autotrophic denitrification in a MLE process and their microbial characteristics by fluorescence in situ hybridization

Spent sulfidic caustics (SSCs) produced from petrochemical plants contain a high concentration of hydrogen sulfide and alkalinity, and some organic matter. Most of the SSCs are incinerated with the auxiliary fuel causing secondary pollution problems. The reuse of this waste is becoming increasingly important in terms of economical and environmental viewpoints. To denitrify wastewater with a low COD/N ratio, additional carbon sources are required. Therefore, autotrophic denitrification has received increasing attention. In this research, SSCs were injected as electron donors for sulfur-based autotrophic denitrification in a modified Ludzack-Ettinger (MLE) process. According to the variations in the SSCs dosage, the efficiencies of COD, nitrification and TN removal were evaluated. Heterotrophic denitrification by organic matter and autotrophic denitrification by SSCs were also investigated. As a result, adequate injection of SSCs showed stable autotrophic denitrification. To investigate some of the harmful effects of SSCs, fluorescence in situ hybridization (FISH) for nitrifying bacteria and Thiobacillus denitrificans was performed. Ammoniaoxidizing bacteria (AOB) and Nitrospira genus showed a similar pattern. Excessive injection of SSCs made nitrifying bacteria decrease and nitrification failure occur because of the high pH caused by the SSCs. The distribution of T. denitrificans was relatively uniform as SSCs were injected. This result means that T. denitrificans are available at high pH.     

Photocatalytic degradation of m‐dinitrobenzene by illuminated TiO2 in a slurry photoreactor

1,3‐dinitrobenzene (m‐DNB) is one of the compounds released to water in discharges during the manufacture of explosives. Its widespread distribution as an environmental contaminant is a potential threat to wildlife and other ecological receptors. Therefore, removal of m‐DNB from aqueous solution is very important. In this work, which is a continuation of our ongoing investigation of the effect of various functional groups in aromatic derivatives, a study of the destruction of m‐DNB in aqueous solution, was carried out using both concentrated solar radiation and artificial UV radiation. It was found that a variety of phenolic intermediates are formed via hydroxyl radicals attacking the parent compound. The effects of the various parameters such as adsorption, initial concentration, catalyst loading, pH and anions on the photocatalytic degradation of m‐DNB was studied. The kinetics of the photocatalytic reaction were also studied. The effect of the second nitro group in m‐DNB was elucidated by comparison with our earlier work on PCD of nitrobenzene. Copyright © 2005 Society of Chemical Industry     

Characteristics of hydrogen evolution and oxidation catalyzed by Desulfovibrio caledoniensis biofilm on pyrolytic graphite electrode

Hydrogenase, an important electroactive enzyme of sulphate-reducing bacteria (SRB), has been discovered having the capacity to connect its activity to solid electrodes by catalyzing hydrogen evolution and oxidation. However, little attention has been paid to similar electroactive characteristics of SRB. In this study, the electroactivities of pyrolytic graphite electrode (PGE) coated with SRB biofilm were investigated. Two corresponding redox peaks were observed by cyclic voltammetry detection, which were related to the hydrogen evolution and oxidation. Moreover, the overpotential for the reactions decreased by about 0.2 V in the presence of the SRB biofilm. When the PGE coated with the SRB biofilm was polarized at 0.24 V (vs. SHE), an oxidation current related to the hydrogen oxidation was found. The SRB biofilm was able to obtain electrons from the −0.61 V (vs. SHE) polarized PGE to form hydrogen, and the electron transfer resistance also decreased with the formation of SRB biofilm, as measured by the non-destructive electrochemical impendence spectroscopy detection. It was concluded that the hydrogen evolution and oxidation was an important way for the electron transfer between SRB biofilm and solid electrode in anaerobic environment.     

脱氮硫杆菌生长特性及其对碳钢SRB腐蚀的防护作用研究

将脱氮硫杆菌(TDN)作用于被硫酸盐还原菌(SRB)微生物腐蚀的碳钢,研究了SRB和TDN生长特性及最适生长条件.利用静态挂片法研究SRB在不同环境下的腐蚀行为,以及TDN的防护效果;并借助扫描电子显微镜、X-射线能谱仪等研究了腐蚀后钢片的形貌及腐蚀产物.结果表明,SRB和TDN生存条件相似并可共存于同一环境;SRB可加速对X70钢的腐蚀,若有TDN共存时腐蚀程度明显降低,且TDN可消耗SRB代谢的具有腐蚀性的硫化物从而减轻SRB对钢基体的腐蚀.     

Heat transfer limitations on nuclear reactor fuel elements

Limitations on heat transfer rates on fuel elements in Canadian heavy-water-moderated reactors are examined. With organic coolant in simple flow geometries, heat fluxes are limited by departure from nucleate boiling, (DNB); in simulated fuel bundles the failure mechanism can be either localized DNB, or coke-out, the formation, deposition and rapid growth of coolant decomposition products on heated surfaces. With boiling light water coolant, critical heat flux (CHF) is caused by DNB at low qualities and by dry-out at higher qualities. Parameters governing CHF in tubes and annuli are fairly well established. Data for fuel bundles are becoming available. Methods of increasing CHF and of rationally setting margins of safety on CHF are being developed.     

油田生产中硫酸盐还原菌的危害及其防治

归纳了硫酸盐还原菌在油田生产活动中的危害,并通过对硫酸盐还原菌代谢机制的研究,深入了解其代谢特点和金属腐蚀机制。在此基础上,全面总结了硫酸盐还原菌的防治方法,包括物理方法、化学方法和生物方法,并提出了硫酸盐还原菌的防治策略和未来发展方向。