Progress of Microbial Enhanced Oil Recovery in Laboratory Investigation

This paper describes a simple, easy process for screening microorganisms, and introduces a laboratory simulation device and process of microbial enhanced oil recovery (MEOR) , which is a necessary research step for trial in oilfields. The MEOR mechanism and the influence of adsorption, diffusion, metabolism, nutrition, porosity, and permeability are analyzed. The research indicates that different microbes have different efficiencies in EOR and that different culture types play different roles in EOR. The effect of syrup is better than that of glucose, and larger porosity is favorable to the reproduction and growth of microbes, thereby improving the oil recovery. Using crude oil as a single carbon source is more appreciable because of the decrease in cost of oil recovery. At the end of this paper, the development of polymerase chain reaction (PCR) for the future is discussed.

Research on the Jilin Oilfield Field Trials of Microbial Enhanced Oil Recovery

This paper describes the experience of Jilin oilfield trials for Microbial Enhanced Oil Recovery (MEOR). A new technique to identify microbes with DNA for MEOR has been established, and useful microbes selected for use in field trials. Behaviors of bacteria activated in the reservoir, oil recovery and water cut, and the viscosity of crude oil produced through huff & puff testing and flooding with molasses-injection tests, have been investigated in situ. CJF-002, which produces biopolysaccharide, is the best among the microbes used for field trials, as it can use molasses as nutrient and produce a small quantity of CO2 and a mass of water-insoluble biopolymer. The metabolic behavior in the reservoir showed that CJF-002 had a good potentiality for MEOR.

Relationship between Microbial Community Characteristics and Flooding Efficiency in Microbial Enhanced Oil Recovery

Microbial enhanced oil recovery (MEOR) is the research focus in the field of energy development as an environmentally friendly and low cost technology. MEOR can bes divided into indigenous microbial oil recovery and exogenous microbial oil recovery. The ultimate goal of indigenous microbial flooding is to enhance oil recovery via stimulation of specific indigenous microorganisms by injecting optimal nutrients. For studying the specific rule to activate the indigenous community during the long-term injection period, a series of indigenous displacement flooding experiments were carried out by using the long-core physical simulation test. The experimental results have shown that the movement of nutrients components (i.e., carbon/nitrogen/phosphorus) differed from the consumption of them. Moreover, there was a positive relationship between the nutrients concentration and bacteria concentration once observed in the produced fluid. And the trend of concentration of acetic acid was consistent with that of methanogens. When adding same activators, the impacts of selective activators to stimulate the indigenous microorganisms became worse along with the injection period, which led to less oil recovery efficiency.

Study of a plugging microbial consortium using crude oil as sole carbon source

A microbial consortium named Y4 capable of producing biopolymers was isolated from petroleum-contaminated soil in the Dagang Oilfield, China. It includes four bacterial strains： Y4-1 （Paenibacillus sp.）, Y4-2 （Actinomadura sp.）, Y4-3 （Uncultured bacterium clone） and Y4-4 （Brevibacillus sp.）. The optimal conditions for the growth of the consortium Y4 were as follows： temperature about 46 ℃, pH about 7.0 and salinity about 20.0 g/L. The major metabolites were analyzed with gas chromatographymass spectrometry （GC-MS）. A comparison was made between individual strains and the microbial consortium for biopolymer production in different treatment processes. The experimental results showed that the microbial consortium Y4 could produce more biopolymers than individual strains, and the reason might be attributed to the synergetic action of strains. The biopolymers were observed with optical and electron microscopes and analyzed by paper chromatography. It was found that the biopolymers produced by the microbial consortium Y4 were insoluble in water and were of reticular structure, and it was concluded that the biopolymers were cellulose. Through a series of simulation experiments with sand cores, it was found that the microbial consortium Y4 could reduce the permeability of reservoir beds, and improve the efficiency of water flooding by growing biomass and producing biopolymers. The oil recovery was enhanced by 3.5% on average. The results indicated that the consortium Y4 could be used in microbial enhanced oil recovery and play an important role in bioremediation of oil polluted environments.

Brief Review on MEOR Technology

As one of the main oil production countries, China pays great attention to the study and application of new technologies to enhance oil recovery. Microbial enhanced oil recovery (MEOR), an advanced technology, is one of the focuses. This paper gives a brief review on the history of the MEOR development and of laboratory-based and field application programmes. Mechanisms of MEOR are presented. Microorganisms can produce gases, acids, surfactants, polymers, all of which are capable of an effective improvement on the hydrocarbon structure, decreasing viscosity and also flooding oil physically under an increased pressure. Early field trials were initiated to utilize microorganisms to recover residual oil or gas. The microorganisms and their reaction products critically have an effect on oil and gas production in many reservoirs in China. Concerning research on metabolites, several field applications in some oil fields indicate that it is very significant to accurately analyse and evaluate metabolites and further select the most suitable microbe. Moreover, the MEOR program is applied in extra-heavy crude oilfields with relatively good results.

绿色荧光蛋白标记在MEOR中的应用研究

为了充分认识目的优势菌种经油藏运移后在产出水中分布的规律与数量,准确分析和客观评价MEOR现场试验效果,利用绿色荧光蛋白(GFP)基因标记目的菌,通过绿色荧光蛋白跟踪监测目的菌的动态信息。构建含有GFP基因的质粒pET-30a(+)-EGFP,并将其成功导入JD中。对构建的JD(gfp)工程菌进行培养发现,该工程菌在含有Kan质量浓度50μg/mL的培养条件下,重组质粒在JD(gfp)工程菌体内传代稳定,绿色荧光的表达稳定。但是在没有选择压力的培养条件下,重组质粒在JD工程菌胞体内有丢失现象。与野生菌混合培养,JD(gfp)工程菌具有很好的配伍性和竞争性,并且不发生重组质粒的水平转移,因此在环境中释放是安全的。

The Selection and Breeding of a Novel Microorganism Strain I and Investigation of Core Model Experiment for MEOR

This paper introduces the results of selecting and breeding a micro-organism, Strain I, and its core model experiment investigation for microbial enhanced oil recovery (MEOR). Strain I was separated from the formation water of the Dagang oil field, with analytical results showing that Strain I is a gram-positive bacillus. A further study revealed that this strain has an excellent tolerance of environmental stresses: It can survive in conditions of 70℃, 30 wt% salinity and pH3.5-9.4. Strain I can metabolize biosurfactants that could increase the oil recovery ratio, use crude oil as the single carbon source, and decompose long-chain paraffin with a large molecular weight into short-chain paraffin with a small molecular weight. The core model experiment shows that Strain I enhances oil recovery well. Using 2 vol% of the fermentation solution of Strain I to displace the crude oil in the synthetic plastic bonding core could increase the recovery ratio by 21.6%.

Laboratory studies of rice bran as a carbon source to stimulate indigenous microorganisms in oil reservoirs

There is a great interest in developing cost-efficient nutrients to stimulate microorganisms in indigenous microbial enhanced oil recovery（IMEOR） processes.In the present study,the potential of rice bran as a carbon source for promoting IMEOR was investigated on a laboratory scale.The co-applications of rice bran,K2HPO4 and urea under optimized bio-stimulation conditions significantly increased the production of gases,acids and emulsifiers.The structure and diversity of microbial community greatly changed during the IMEOR process,in which Clostridium sp.,Acidobacteria sp.,Bacillus sp.,and Pseudomonas sp.were dominant.Pressurization,acidification and emulsification due to microbial activities and interactions markedly improved the IMEOR processes.This study indicated that rice bran is a potential carbon source for IMEOR.

微生物提高油藏原油采收率进展

文章从油藏中普遍存在的采油微生物类群及其驱油机制、微生物采油技术的矿场应用、采油微生物的响应等方面对油藏微生物及其提高原油采收率进展进行综述.同时从营养剂在油藏储层中的分布、油藏环境下微生物生长代谢活性、油藏微生物定向调控等方面阐述了微生物采油技术发展的基础问题.

反硝化产气温和食酸菌G21及其在油田生产中的应用潜力

以反硝化产气菌在油田生产中的潜在应用为出发点,从油田产出液中分离到一株兼性厌氧反硝化产气菌G21,对菌株G21进行了16S rRNA基因和反硝化功能基因分析,并基于产气效果对最佳碳源及碳氮比进行优化,测定产生气体的组分,从G21与油藏产出液互配性角度探究了G21在油田生产中的应用潜力。结果表明:菌株G21与Acidovorax temperans PHL的16S rRNA基因相似性达到99.36%,属于温和食酸菌;菌株G21含有膜结合硝酸盐还原酶(Nar)、周质硝酸盐还原酶(Nap)、亚硝酸盐还原酶(Nir)、一氧化氮还原酶(Nor)和氧化亚氮还原酶(Nos)的编码基因;气体组分分析结果证实,菌株能够将硝酸盐氮还原为氧化亚氮和N_(2);糖类是其反硝化产气的最佳碳源,碳氮比为5∶1时(葡萄糖5000 mg/L(以化学需氧量COD计)、NaNO_(3)-N 1000 mg/L),产气量(气液比)达到1∶1;在油藏产出液中,G21产气性能良好,且能压制硫酸盐还原菌的生长。可见,反硝化产气温和食酸菌G21在防控油藏硫酸盐还原菌和产气提高原油采收率方面具有一定的应用潜力。

XJ-21菌株在胍胶压裂液体系中破胶驱油的复合性能

在储层压裂改造过程中,胍胶压裂液体系低温破胶难,储层改造效果差,是新疆油田油藏开发亟待解决的关键技术难题。针对这一技术难题,将微生物强化采油技术应用于压裂液体系中,从新疆油田吉7井区烧房沟组采集到油泥,通过对样品中微生物的富集培养及分离,筛选得到一株能够高产生物表面活性剂的菌株,将其命名为XJ-21。结合菌落形态观察、革兰氏染色及16S rRNA序列分析结果,XJ-21菌株被鉴定为枯草芽孢杆菌(Bacillussubitlis)。FTIR分析确定XJ-21代谢产物中的生物表面活性剂与环脂肽类结构一致。XJ-21菌株与外源ZW-027菌株复配后,复配体系对油藏环境条件具有广泛适应性,不仅在温度为35~55℃的范围内可以产生物酶使胍胶冻胶破胶,还可在50℃下降低样品所在区块的原油黏度,降黏率可达95.45%。在水驱后,使用复配体系驱油与仅用水驱技术相比可以提高10.14%的驱油率。

“双碳”目标下绿色提高采收率技术路径与实践

“碳达峰、碳中和”目标下,油气生产行业在持续增产稳产、确保能源安全的前提下,需要加强负碳、零碳和低碳技术创新,促使产业转型升级。新技术、新工艺、新材料的研发赋予了绿色低碳提高原油采收率技术新的内涵。理论研究与矿场实践表明:CO_(2)驱油、CO_(2)压裂增产、空气(减氧空气或N_(2))驱油、生物质基驱油、微生物基驱油技术碳减排效应明显,为提高原油采收率领域碳中和提供了新路径。未来将继续优化绿色提高原油采收率技术路径,构建新一代绿色低碳提高采收率工程技术体系,开展全流程全生命周期碳减排潜力研究,探索绿色低碳提高采收率技术定量表征方法。

微生物调剖技术的工程应用进展

注水开发目前是我国多数油田主要的开发方式。由于地层的非均质性导致注入水易沿着高渗透带发生窜流,降低吸水剖面,严重影响注水开发效果。常见的化学调剖剂通常有工艺复杂、稳定性差、污染严重和成本高等不足。近年来微生物提高采收率技术在国外迅速发展,逐渐受到国内学者的广泛关注。本文总结微生物调剖技术机理并综述了国内外微生物调剖技术的发展现状,最后提出未来微生物调剖技术应用的挑战与前景。

激活内源微生物提高原油采收率技术

微生物采油技术可按微生物来源分为外源微生物采油和内源微生物采油两大类。本文综述了通过注入营养剂和混气水激活油层内本源微生物的采油技术 ,该项技术的工艺较简单 ,在俄罗斯已进入较大规模的矿场应用试验。综述的论题包括 :绪言 ;基本原理 ;矿场试验及相关研究 ;矿场试验设计 ;矿场试验跟踪监测 ;对中国微生物采油技术发展的意义。图 1表 3参 4 0。

PCR-DGGE方法分析原油储层微生物群落结构及种群多样性

使用基于 16 S r DNA的 PCR- DGGE(变性梯度凝胶电泳 )图谱分析结合条带割胶回收 DNA进行序列分析 ,对新疆克拉玛依油田一中区注水井 (12 # 9- 11)和与该注水井相应的两个采油井 (12 # 9- 9S、13# 11- 8)井口样品微生物群落的多样性进行了比较并鉴定了部分群落成员。 DGGE图谱聚类分析表明注水井与两油井微生物群落的相似性分别为 30 %和 2 0 % ,而两油井间微生物群落结构的相似性为 5 4 %。DGGE图谱中优势条带序列分析表明注水井样品和油井样品中的优势菌群为未培养的环境微生物 ,它们与数据库中 α、γ、δ、ε变形杆菌 (Proteobacteria)和拟杆菌 (Bacteroidetes)有很近的亲缘关系。 DGGE与分子克隆相结合的分子生物学方法在研究微生物提高原油采收率 (MEOR)机理 ,以及指导

微生物降解稠油及提高采收率实验研究

微生物采油技术以其成本低、无污染、经济效益好的优势 ,日渐成为一项重要的三次采油技术。该技术的主要机理就是利用微生物降解原油的重质组分 ,降低原油粘度和凝固点 ,以达到改善原油物化性质的目的。笔者从原油、油田污水和海水中共分离、选育出能降解沥青质 ,能耐温达 80℃、矿化度 30 0 0 0 0 mg/ L的微生物菌种及组合。并以其对青海、胜利、辽河等油田原油进行了实验研究 ,讨论了能有效降解原油中沥青质的兼性菌的选育、降解效果以及采油过程中的现场应用。根据实验 ,所选育的兼性菌组合对青海原油处理 2 4h后 ,其沥青质可降低 2 0 %。现场试验显示 ,生产井注入菌液 2 0 d后 ,3个月内的日均产量提高了 9% ,油井的热洗周期延长了 2 .

本源微生物驱油机理研究及现场应用

对大港油田本源微生物驱现场试验过程中流体的微生物学特征、地球化学特征及生产动态进行了监测 ,研究了本源微生物提高原油采收率的机理。随注入水一同注入大量含氮、含磷盐的物质及空气 ,使生态系统中的微生物和理化特征发生了显著变化。地层水中嗜热微生物的数量和活性分别增加了 10 3 ～ 10 5倍和 10～ 10 3 倍。烃氧化菌的激活导致了注入水在近井地带原油的氧化及低分子脂肪酸含量增加。原油的生物转化产物刺激了发酵菌、硫酸盐还原菌及产甲烷菌的生长 ,微生物的代谢产物有利于原油的采出。从生产动态分析可以看出 ,经生物技术处理后 ,83 %的生产井见到了效果 ,3年共增油 8874t ,投入产出比达到 1∶5 2。

微生物采油技术的研究进展及展望

经过70多年的发展,微生物采油技术(MEOR)已经成为继热力驱、化学驱、聚合物驱之后的第4种提高采收率的新的"三采"技术,并且越来越受到人们的重视。在介绍微生物采油技术发展历史的基础上,重点阐述了微生物采油的机理、菌种筛选和评价的方法以及应用该技术的油层条件和应用前景,并提出了一些建议。

稠油降黏开采技术研究进展

综述了稠油降黏开采技术的近期进展,重点是乳化降黏法和微生物法中生物表面活性剂的作用,论题如下。前言:国外、国内稠油油藏及其开采。①稠油组成及其高黏实质。②物理法降黏,包括掺稀油法和蒸汽、电加热法,新疆塔河油田一口井用掺稀油法试油开采。③化学法降黏,包括催化水热裂解、乳化、破乳及油溶性降黏剂,简述了降黏机理,介绍了国内乳化降黏剂研制和应用方面的成果。④微生物法降黏:包括微生物采油机理、生物表面活性剂性质、生物表面活性剂用于EOR、国内产表面活性剂菌种筛选。参44。

微生物采油室内研究进展

综述了微生物提高原油采收率 (MEOR)室内研究新进展 ,涉及的论题如下。①MEOR用菌种筛选 :原则 ,要求 ,一种简单筛选程序 ,性能评价项目和方法 ,营养液组成和选择 ;②MEOR机理简述 ;③岩心模拟实验 :装置和程序 ;④MEOR研究中的PCR技术 (聚合酶链式反应技术 ) :菌种检测 ;⑤展望。