Application of Apollo Greenzyme Unblocking Technique in Baise Oilfield.

Deng Zhengxian, Liang Yuan'an, Weng Gaofu , Sun Guijun , Ran Shaomin. Guangxi Oil Production Plant, SINOPEC Southwest Oil & Gas Company, Guangxi Tiandong 513500. Abstract: A serious problem in the Baise oilfield is that partial oil wells make sand flow, emulsification and wax deposits within the formation plugging in oil layers.  Conventional acidizing treatment can not be used in some oil wells because of the bad well condition and sand production.  Apollo Greenzyme unblocking techniques were introduced to apply in Baise. This paper gives a way of operating with the original production string.  After analyzing and discussing the working mechanism of Greenzyme unblocking agent, 14 experiments were done including 13 wells, of which 12 wells were effective in unblocking and the increasing oil production.  The efficiency of stimulation was 85.7% with 270.6 metric tons incremental oil recovered. http://www.zshg.com/zwny/7-5-61.htm

Greenzyme® Steam Stimulation at Shengli Oilfield,, Well #826. Shengli, China.

January 10, 2006. English translation from Chinese showing significantly improved production from a first steam cycle without enzyme fluid (<3,000 bbls oil) to the second steam cycle which reduced the steam load used by 20%, but injected diluted enzyme fluid as a pre-cursor (>21,000 bbls oil produced). Both daily production and production for the second steam cycle rose significantly, despite the reduction in steam. The depth of the well indicated (1,700 meters) makes it likely the steam injected reached the intended zone as hot water rather than steam. Well produced a heavy crude with density =1.03. Viscosity 025-30 MPa’s. The addition of Greenzyme® enhanced production.

Research on pilot test of biologic-enzyme enhanced oil recovery in Gangxi oil reservoir of

Dagang Oilfield

Li Daoshan,Shi Mingyi,Ni Fangtian et al. Research Institute of Oil Production Technology,Dagang Oilfield Company,CNPC,Dagang,Tianjin City,300280,China  The feasibility of the application of biologic-enzyme for enhancing oil recovery by single well huff and puff in complex fault-block reservoirs in Dagang Oilfield was researched by analyzing biochemical properties and interfacial activity of biologic-enzyme and oil displacement efficiency on different wettability cores. Modern measuring results indicate that biologic-enzyme mainly makes up of protein enzyme,alcohol de-hydrogenase (ADH), xylanase enzyme and so on with high biological activity. The total protein content is about 10~3μg/mL. The interfacial tension of biologic-enzyme fluid and crude oil is in the range of 10~(-1) to 10~(-2)mN/m with relatively lower activity than that of other common surfactants used in the combination flooding. Biologic-enzyme is able to emulsify some crude oil. When the concentration is over 4 percent, the emulsification effect of crude oil is gradually improved. The wettability of rocks change after biologic-enzyme molecules are absorbed on the rock surface,which makes the rock surface become much water-wetting. The pilot test in biologic-enzyme recovery well groups presents significant effect on decreasing water production and increasing oil production,and the ratio of input to output is 1:12 and the crude oil recovery rate is more than 3 percent. The biologic -enzyme enhanced oil recovery technology can be applied in homogeneous reservoirs with middle permeability or low permeability,and in reservoirs with high content of resin and asphaltene. If the biologic-enzyme system can stay in the reservoir for a while,its recovery effect can be better. http://en.cnki.com.cn/Article_en/CJFDTOTAL-YQCS200904023.htm

Experimental Study on Apollo Enzyme Blocking Removal Technique

WU Chao (Research Institute of Perculation and Fluid Mechanics, Chinese Academy of Scrences, Langfang 065007, Hebei, China)HUANG Li-xing, YU Li, CUI Qing-feng (Langfang Branch of Research Institute of Petroleum Exploration and Development, CNPC, Langfang 065007, Hebei, China)  The characters and application of Apollo enzyme were introduced. For studying bioenzyme blocking removal mechanism, the blocking of organic scaling is simulated by distilling formation oil from an oilfield, an experiment for capillary absorbing is carried out for detecting the interface tension between oil/water, oil/enzyme solution, by which the gas chromatogram of saturated hydrocarbon both before and after enzyme usage is obtained. It is found out that Apollo enzyme has the function of changing rock wettability, reducing oil-water interfacial tension and organic scaling stripping, degradation, a physical simulation test is made for removing organic blocking by using cores packing with sand from the oilfield. It is demonstrated that it is feasible for simulating organic scaling blocking by injecting cores with distilled oil. The result shows that after 8% Apollo enzyme blocking removal agent prepared with formation water exposed for 48h is used, the permeability on the cores blocked by organic scale recovers to 90% or more, permeability increases more 13.78% than that before blocking, and better blocking removal effect is achieved. http://en.cnki.com.cn/Article_en/CJFDTOTAL-JHSX200703085.htm

RESEARCH AND APPLICATION OF BIOLOGICAL BLOCKING SOLUTION ON ULTRA-DEEP

HEAVY OIL INJECTION WELLS

Mu Jin-feng.Turpan-Hami Oilfield Company lukqin Oil Production Plant Shanshan,Xinjiang 838202 Lukqin oilfield is a deep heavy oil field,at room temperature with water injection development,achieving better development results. However,with the total injection volume of oil increased,pressure has been close to the ground water system pressure,injection wells due to the growing use of pressure dropping by injection of conventional acid for a short period have little profit. In this paper,from the study of the blocking mechanism of heavy oil wells,biological blocking solution process is proposed. Through the application,the results are significant,which provides a step-down new technical idea for heavy oil wells with a broad promotion and application prospects. http://en.cnki.com.cn/Article_en/CJFDTOTAL-XJSY201001011.htm

Research and application of biological enzyme as plug remover for stimulation

SU Chonghua1,2(1.Southwest Petroleum University, Chengdu 610500, China;2.CNOOC Ltd.-Zhanjiang, Zhanjiang 524057, China)  In order to remove the formation blockage resulted from heavy component pollution and drilling fluid pollution, this paper studies the plug removal performance of two kinds of enzyme(Apollo and SUN) now widely used. Through the appearance analysis, stability study, analysis experiments about bacteria content, protein, sugar component and bio surfactant and interfacial tension measurement, we recognize the roles of two enzymes in improving rock wettability and sweeping oil, and their ability to emulsify crude oil and plug removal mechanism. Simulation experiment results demonstrate that two enzyme can release the heavy component blockage in different degree, especially the Apollo enzyme solution prepared with formation water can remove the formation blockage resulted from drilling fluid. The paper introduces the well selection principle of plug removal with biological enzyme, field operation technique scheme, operation scheme and effect evaluation. Plug removal operation was implemented in 2 oil wells of offshore oilfield in terms of 1.8m treatment radius of and 4% mass fraction of Apollo solution and the results of the reservoir stimulation are successful giving a reference to similar oilfield. http://en.cnki.com.cn/Article_en/CJFDTOTAL-SYZC200805028.htm

Research and Application of Plug Removing Technology with Enzyme

Zou Qingteng,Wang Xiyou(Santanghu Oil Production Plant, Tuha Oilfield Company, PetroChina, Hami 839009, Xinjiang) Shanshan oilfield is a typical low porosity and super-low permeability reservoir chartered by middle and higher water-cut stage, complex well pollution types and lower acidification effective rate. Enzyme is a biological preparation extracts from the nature with no injury to equipment, environment and personnel, it has function of biodegradation, which can be able to strip crystal in near wellbore area; strip wax and asphaltene accumulated on the rock grain; change rock wettability form oil-wet to water-wet; reduce flow resistance of oil in formation void. With features of economic, high-efficiency and environmental protection, the technology is applied successful to two wells in Shanshan oilfield. http://en.cnki.com.cn/Article_en/CJFDTOTAL-THYQ200704017.htm

Application of Biologic Enzyme to Remove Blockage and Improve Production in Chengdao

Oilfield

Liu Xiao-mei1, Zhao Xia2, Jiao Heng-de3 (1. Gudao Oil Production Plant, SINOPEC Shengli Oilfield Co., Ltd.; 2. Marine Oil Production Plant, SINOPEC Shengli Oilfield Co., Ltd.; 3. Jindao Industry Co., Ltd., Shengli Oilfield) Due to impurities accumulation and colloid and asphaltene crustation at immediate vicinity of wellbore, there is a blockage in the strata of some wellblocks in Chengdao Oilfield, filtrational resistance increases, strata deliverability is inadequate, and oil wells cannot be put into normal production. Blockage remover with biologic enzyme is used in the oilfield to remove blockage successfully. This paper briefly introduces the causes of reservoir blockage and the mechanism of using biologic enzyme to remove blockage and improve production as well as the field application in recent years. It is regarded that production could be improved greatly and remarkable economic benefits could be obtained by using the new method. http://en.cnki.com.cn/Article_en/CJFDTOTAL-SYKT201003015.htm

EOR Pilot Tests With Modified Enzyme

Feng Qingxian,Wang Juanjuan,Liu Min,et al.(Oil Production and Technology Institute,Dagang Oilfield Company,CNPC,Tianjin 300280,China) In order to verify the enhanced oil recovery effect of modified enzyme,micro and macro evaluations were conducted to understand its EOR mechanisms by using various fluids and conditions. At reservoir temperature of 50 to 80℃,lab experiment indicated that the modified enzyme solution was adaptable to both light and heavy oil and was not sensitive to minerals, water with bivalent cation and high salinity. The enzyme working performances were further enhanced with microorganism occurrence in the solution. Micro modeling experiment revealed that spontaneous emulsification and solubilization could take place between the modified enzyme and crude with emulsion particle of 2 to 6 μm in diameter,which is produced through stripping as a result of solubilization. Core flooding experiments presented that desorbed crude volume and displacement efficiency were related to modified enzyme concentrations which usually ranged from 5% to10% with the optimum being 8%.In optimal conditions,recovery can on averagely be increased by 16.9%.Pilot test was carried out,and had achieved additional oil production of 2,920 t.It shows that the tech has good foreground. http://en.cnki.com.cn/Article_en/CJFDTOTAL-DKYT200804030.htm

Study on Pilot Test of Plug Removing Technology with Enzyme

YANG De-hua (Oil Production Technology Institute, Dagang Oilfield Company, Tianjin 300280, China)DONG Zhi-xue (Tianjin Engineering Technical Institute, Tianjin 300280, China)LUO bo (Petroleum Exploration & Development Research Institute of Dagang Oilfield, Tianjin 300280, China) Arming at serious sand production, wax precipitation, formation blockage phenomena in part wells in Dagang Oilfield, at the same time, well condition and sand production can not use conventional acidization broke down technology, biological enzyme broke down technology was introduced. After analyzing the mechanism of biological enzyme broke down agent, immobility limb method was used in Dagang Oilfield Gangxi 7-6 Well Group. Good effects of oil drive, broken down and oil increment are obtained, the oil increment in single well is more than 2300 t, input-output ratio is 1:3.47. http://en.cnki.com.cn/Article_en/CJFDTOTAL-JHSX200806084.htm

APPLICATION OF APOLLO BIOLOGICAL ENZYME ACIDIZATION TECHNIQUE IN BAISE OIL

FIELD

Deng Zhengxian, Liang Yuanan, Weng Gaofu, Sun Guijun, Ran Shaomin(Guangxi Petroleum & Natural Gas Development Company, SINOPEC, Tiandong 513500, Guangxi Province, China)  Considering the problems of producing sand, emulsification, paraffin deposition in some oil wells and bridge blinding in strata in Baise Oil Field, which resulting to that the technique of conventional acidization can not be used in part of wells due to well situations and producing sand,so the technique of Apollo biological enzyme is introducing in. After analyses on acidization mechanism of Apollo biological enzyme, constructing method of no-moving string is adopted. After 14 constructions in 13 wells in Baise Oil Field,12 times obtain the effects of acidization as well as increase of output of crude oil, with the effective ratio of measure to 85.7%, accumulated output of crude oil increased 270.6t. The ratio of investment and output is 1:1.74 and the technique is simple, economic and effective, having the potential to extend. http://en.cnki.com.cn/Article_en/CJFDTOTAL-NFYQ200601017.htm

Experimental research on the changing wettability of rock surface using biological enzyme.

Wang Yuan,Li Zhaomin,Li Binfei et al. Wang Yuan,Hydromechanics Teaching and Research Department, Petroleum Engineering Institute,University of Petroleum,Dongying City,Shandong Province, 257061,China  Based on the measuring standard of rock wettability and using optical projection to measure contact angle of rocks, the experiments on the changing wettability of rock surface by biological enzyme include the changes of rock wettability, capillary force and adhesion work after the act of rock with biological enzyme. Research results show that the biological enzyme can change capillary force of waterflooding oil evidently, accelerate flow of remaining oil, and enhance the recovery efficiency of oil reservoir. http://en.cnki.com.cn/Article_en/CJFDTOTAL-YQCS200501025.htm

Technique of Pressure Decreasing and Injection Increasing by Biological Enzyme in the Low

Permeability Oilfield

Cai Yanhua (No.10 Oil Production Plant,Daqing Oilfield Co.,Ltd.,Daqing Heilongjiang 166405)  Biological enzyme can make residual oil saturation drop for turning wettability of rock surface to water wet and making crude oil fall off from rock particles surface. It also can solve the problems of high injection pressure and poor response of the oil well in the low permeability oilfield and then enhance displacement efficiency. The properties of the biological enzyme were evaluated through the laboratory experiments on displacement efficiency, interfacial tension,and characteristic of surface adsorption,corrosion behavior and depressurization of the biological enzyme. The results show that when the concentration of the biological enzyme is 2.0%,the interfacial tension is low and injection pressure drops by 51.4% averagely ,and it has no corrosiveness for N80 steel. So 0.006PV of the biological enzyme should be injected according to the comprehensive factors. In the field,six injection wells and their connected 24 oil wells make up of the test well group in the tested block of A oilfield. Cumulative injected original enzyme is 270t and total injected enzyme solution is 11422m3.After one year,injection pressure dropped and apparent water injectivity index rose,and interbedded injectivity behavior was improved in the injection wells. In the connected oil wells ,oil production rose a little and composite water cut has no change and rate of formation pressure recovery increased obviously. And more oil was produced with 3519t of cumulative incremental oil production and interval rate of production enhanced by 0.38%.It may help to establish an efficient displacement system in waterflooding in peripheral three-type reservoirs. http://en.cnki.com.cn/Article_en/CJFDTOTAL-SYZW201008013.htm

Use of Enzyme Preparate Greenzyme for Removing Inorganic-Organic Precipitate From

Sanding Heavy Crude Oil Well

WANG Qing 1, ZHAO Ming-Chen 1, MENG Hong-Xia 2, YANG Feng 1, YIN Zhi-Qing 1 (1. Dongxing Oil Production Factory, Shengli Oilfield Company, PetroChina, Dongying, Shandong 257094, China; 2. College of Petroleum Engng, University, of Petroleum, Dongyin  The principles of synthesis and the unique properties of enzyme preparate Greenzyme of Apollo Separation Technolgy Inc., USA, are presented briefly; the mechanisms involved in removal of blockages from sanding crude oil wells by this kind of enzyme (with main action of the enzyme being separation of fine sand particles from viscous crude) are discussed preliminarily; the well selection, use level of enzyme preparate, technology of enzyme treatments are described; the situation of and the enzyme treating results for well Y8-52 are introduced in some detail. After mechanical sand controlling measurements performed, well Y8-52 produced viscous heavy crude together with fine sand and was plugged by crude/sand mixture and the productivity of the well was cut down. Treating the well with Greenzyme notably increases the productivity of liquid and oil and the liquid level in the well and decreases the water cut (from 30-50% to 4-2%). http://en.cnki.com.cn/Article_en/CJFDTOTAL-YJHX200201006.htm

Experimental Study on Plug Removal Agent in Heavy Oil Reservoir with Biological Enzyme

CHEN Ping-zhong( School of Graduate, Research Institute of Petroleum Exploration and Development, CNPC, Beijing 100083, China; Key Laboratory of Oil and Gas Drilling and Production of Hubei Province; College of Petroleum Engineering, Yangtze University, Jingzhou 434023, Hubei, China)WANG Yuan (School of Graduate, Research Institute of Petroleum Exploration and Development, CNPC, Beijing 100083, China)  The principles for plug removal with biological enzyme in heavy oil reservoir were introduced in detail, biological enzyme could be used to reduce the interfacial tension between oil and water, could change the wetting ability of rock, which might lead to the breakaway of resin and asphaltine attached to the rock surface; at the same time the fine sand in wire wrapped liner could be removed. Core displacement test results show that plug removal in cores with the permeability higher than 1μm2 is more effective than that with the permeability lower than 1μm2. The results of field application demonstrate that biological enzyme can relieve the plug in heavy oil reservoir effectively and improve the oil production rate, it has a good perspect for heavy oil reservoir development. http://en.cnki.com.cn/Article_en/CJFDTOTAL-JHSX200806085.htm

Mechanism Study on the Breakdown of Drilling Fluids Using Biological Enzymes

YANG Qianyun, GUO Baoyu, SHEN Li,YUAN Li Drilling Engineering Technology Service, Shengli Petroleum Administration, Dongying, Shandong 257064,China  Mud cake can be removed by adding biological enzymes into a drilling fluid, protecting reservoir permeability from being damaged. A drilling fluid was formulated through laboratory exponents, which has good rheology, inhibitive capacity, lubricity and a filtration rate of almost zero. This drilling fluid contains mainly cellulose, modified starch and biopolymer. Different biological enzymes are added to this fluid. The breakdown mechanisms of these enzymes are discussed in this paper. Laboratory experimental results showed that mud cakes can be easily removed by some specific enzymes. Compared with other mud cake removal methods, biological enzymes can remove mud cakes much more completely, thus leading to a higher permeability recovery. Furthermore, the enzymes used are environmentally friendly. http://en.cnki.com.cn/Article_en/CJFDTOTAL-ZJYW200903005.htm

Study on the Degradation of Mud Cakes with Bio-enzymes

YANG Qianyun, GUO Baoyu, SHEN Li,YUAN Li,QIN Tao Drilling Engineering Technology Service, Shengli Petroleum Administration, Dongying, Shandong 257064,Chin Bio-enzymes can be used to remove mud cakes after a well is completed. The bio-enzymes,when go into the pore throats, can improve the flowability of the crude oil,or change its flow direction,thus increasing the swept volume of injected water,and oil recovery. Using DO attenuation method, six additives were selected and the final optimized formulation was determined through orthogonal tests. Laboratory study showed that the formulated drilling fluid has good rheology, lubricity (EP friction coefficient is less than 0.15) and inhibitive capacity (shale swelling is reduced to 88.54% compared with 10% KCl solution). This fluid is stable at 120 ?.Percent permeability recovery is as high as 90%. Field application also showed good results. http://en.cnki.com.cn/Article_en/CJFDTOTAL-ZJYW200906000.htm

Research and application on LS biological enzyme blocking removal technique

WANG Jian-Guo,WU Chao(Beijing FLTY Petroleum Science & Technology Corp. Ltd.,Beijing 100083,China)   In order to remove the compound blocking resulting from organic and inorganic scaling in oil production wells or water injecting wells, LS biological enzyme was invented. The organic scaling was simulated by oil residue containing fine sand which were taken from an oilfield oil storage tank in China. The contact angle of piezoid polluted by oil residue was tested before and after LS biological action,the interface tension between oil/water,oil/enzyme were also tested,as well as the gas chromatogram of saturated hydrocarbon both before and after enzyme usage was obtained. The physical simulation test is made for removing organic blocking by using cores packing with oil sand from this oilfield. The contact angle reduced from 103.78° to 0° after LS biological enzyme action, oil/water interfacial tension reduced from 15.54 mN/m to 0.4×10-2 mN/m, the quality content of light hydrocarbon increased and that of heavy hydrocarbon decreased. The optimal concentration of LS biological enzyme is 6%~10%,the optimal action time is 3~4 d. After LS biological enzyme blocking removal,the permeability on the cores blocked by organic scale recovers to 90% or more,permeability increases more 27.06% than that before blocking,and better blocking removal effect is achieved. The field test result on one production well of this field indicated that the oil production rate after blocking removal was more than the highest rate in production history,the water cut was reduced by 23.7%,liquid production increased by 3.03 t/d,oil production increased by 3.82 t/d,useful life was more than 4 months,input-output ratio reached 1:8.5. http://en.cnki.com.cn/Article_en/CJFDTOTAL-DQSY200905018.htm

APOLLO ENZYMATIC BLOCKING TECHNOLOGY LABORATORY TEST

Wu Chao, Huang Lixin, YU Li, CUI Qing-feng, China Petroleum Exploration and Development Institute, Langfang, Hebei, Langfang, 065007 Abstract: About the Apollo performance characteristics and application conditions of the enzyme. To study the blocking mechanism of the biological enzyme, distillation in an oil field oil in place methods to simulate the formation of organic dirt clogging the capillary suction test, determined interfacial tension of oil / water, oil / enzyme solution, and before and after the enzymatic crude oil saturated hydrocarbons by gas chromatography analysis and found that Apollo enzyme can play to change the wettability, reduce the interfacial tension and peel, degradation of organic the role of the scale. the core of the oil sand filling of the oil field to lift Apollo enzyme blocked by the organic scale physical simulation experiment proved the feasibility of the distillate simulation of organic dirt clogging Note to the core, results showed that the preparation of the formation water of 8 % Apollo enzymatic blocking agent for 48h, the average permeability of the organic dirt clogging the core of the recovery rate can reach 90% penetration than clogging an average of 13.78% played a good plugging . 2007-08 http://d.wanfangdata.com.cn/periodical_jhsyxyxb200703038.aspx 

THE APOLLO DEPLUGGING QIAOKOU OILFIELD

Chen Xingwu, Shen governance Kay, Sinopec Zhongyuan Oilfield Company, Shandong Dongming, 274 511 Abstract:Apollo plugging agent is a new and efficient catalyst, its main features are: the oil and its attachments to the separation can be used repeatedly to humans and the environment pollution-free, is environmentally friendly products, but does not occur to a reservoir of new pollution Apollo plugging agent Mechanism and effect of oil fields in the Central Plains Hashiguchi explore and promote the use of the technology provides hands-on experience. 2004-02 http://d.wanfangdata.com.cn/Periodical_tzyqc200401023.aspx

LOW PERMEABILITY OILFIELD BIOLOGICAL ENZYME FLOODING PILOT TEST

WANG Zhi-yao CNPC Daqing Oilfield Co., Ltd., Daqing, Heilongjiang 163712 Abstract: The Daqing Chaoyanggou reservoir case of the ultra-low permeability reservoirs, the average penetration rate of 10 × 10-3?m2 geological causes poor absorption capacity of the injection wells, injection pressure, poor oil recovery. To solve the above problems, moving 89 blocks buck by injection pilot test of biological enzymes. biological enzyme is a biologically active protein product of the modern biological engineering technology developed, has to change the wettability of rock surface and reduce the interfacial tension, its complex distribution system displacing agent chemical reagents and separate biological molecules are more stable. site flooding technique of application of biological enzyme injection pressure decreased by 10.8%, water absorption index increased cumulative oil 5 860 t. and advice that will be used as a major success of the block test. for the same type of reservoir development experiences. 2010-10 http://d.wanfangdata.com.cn/Periodical_tzyqc201006027.aspx 

APOLLO ENVIRONMENTAL EFFECT OF ENZYMES ON THE INTERIOR WELL OF BLOCKING

SOLUTION

Xiuhua  Sun Dejun  Department of Chemistry, Daqing Normal University Department of Chemistry, Daqing Normal University Abstract: Broken down by core laboratory studies have shown that, Apollo environmental enzymes into the ground, you can almost wellbore crystallization of the rock particles deposited on the wax and asphaltene peeling off, and clear the flow channel, induction, activation, poly and oil flow into the zone, decrease in crude oil in the pore flow resistance, environmental protection flooding the Apollo area affected by the oil activity, while improving the stability of the rock properties of oil-producing areas, the rock wettability wet into wet by the oil and protect the reservoir, an increase of Water injection capacity, and by plugging the dual role of activation induced displacement oil production, oil field injection well to increase blood pressure injection and production wells plugging the purpose of increasing production. Oil extraction process, the organic and inorganic scale heavy-duty composite deposition, formation particle migration, such as clay hydration expansion will result in wells and water wells near wellbore plug, resulting in lower productivity [1,2,3]. At present, acidification, fracturing operations have become domestic wells and wells, and reservoir engineers to lift the blockage near wellbore, expanding or extending the gas flow path, increasing production by injection of the important technical measures and development tools, especially for .2007-02-028 www.cnki.com.cn/Article/CJFDTOTAL-DQGZ200702028.htm   

OILFIELD LOW PERMEABLE RESERVOIR FLOODING TECHNIQUE OF ENZYME

High Dongmei , Zhejiang University Abstract: Oilfield is a typical low permeability oil fields, after two years of flooding, some blocks of the original well network adaptability is poor, oil wells, is difficult to establish effective inter-drive system, low oil pressure recovery, the current formation pressure is lower than the original pressure, and even lower than the saturation pressure, resulting in waterflooding oil recovery is low, and measures to tap the potential lack of stimulation, there is a restricted field of sustainable development. To compensate for these limitations and lack of technical measures to further enhance the low permeability oil exploration for the ultimate recovery of the non waterflooding technology, to establish an effective drive system to achieve cost-effective to use, the introduction of enzyme recovery technology to conduct biological enzyme block, oil field test. In this paper, oilfield reservoir characteristics of the geological features and the low permeability reservoir proposed for the development of enzyme production technique, mainly discusses the characteristics of enzymes, performance, biochemical mechanism, displacement mechanism, and biological experiments and enzyme enzyme displacement field test results. Laboratory experiments showed that the enzyme has a unique flooding mechanism, which can eliminate the boundary layer of rock; change the reservoir wettability state, reduce the wetting angle, the reservoir rock change from hydrophilic lipophilic; lower reservoir interfacial tension of the rock particles; thereby reducing the reservoir of crude oil in the pores of the flow resistance, so that the release of oil from the surface of rock particles, through the role of dialysis, to broken down, the effects of flooding. Enzyme site in the oil displacement test throughput and achieve the expected goal, and achieved a significant increase in oil effect, so that enzyme technology as the oilfield oil reservoir to improve the development effectiveness of low permeability and effective technical means. 2008-07 http://cdmd.cnki.com.cn/Article/CDMD-10335-2009024658.htm 

RESEARCH ON THE PLUGGING REMOVAL TECHNIQUE OF LOW-COST BIO-ENZYME IN ANSAI

OILFIELDS  

Zhang Hao,Zhang Junfeng,Wu Fengna,et al Abstract: Ansai oilfields belong to the low permeability oil reservoir, so when the stratum is plugged,the output of oil wells will be decreased greatly. According to the mechanism of stratum plugging and the physical property of Ansai oil reservoir, the plugging removal technique of environmental bio-enzyme was evaluated in the laboratory, and then is applied to the fields, achieving the better effect of increasing oil. The practical application indicates that the plugging removal technique of environmental bio-enzyme possesses a good applicative prospect, because of needing no movement of pipes, its construction being simple, its measures having better effect, and its operation cost being low. 2011-01 http://en.cnki.com.cn/Article_en/CJFDTOTAL-SYJD201101004.htm 

MECHANISM AND ADAPTABILITY OF REMOVING BLOCK BY ENZYME-AQUEOUS PREPARATION

ZHAO Jin-cheng, ZHANG Shu-huan (Research Institute of Development Engineering, COSL, Beijing 101149, China) Abstract: Using enzyme-aqueous preparation to remove blocks in porous media during production is a new high-tech. On the basis of latest research results in enzymology and enzyme engineering principles,combined with new understandings in contemporary reservoir engineering theory,in-depth discussion of such a blocking mechanism is made to lay a solid foundation for the practical application of the enzyme-aqueous preparation. According to the technical requirements for oilfield development,the adaptability of blocking operation is analyzed,which provides scientific basis and technical support for engineering design and field operation. 2011-06 http://en.cnki.com.cn/Article_en/CJFDTOTAL-XJSD201106023.htm

OIL DISPLACEMENT AND DREDGING MECHANISM RESEARCH OF APOLLO ENVIRONMENTAL

ENZYME ON WELL

SUN De-jun(College of Chemistry and Chemical Engineering, Daqing Normal University, Daqing 163712,China) Abstract: According to the characteristics of Apollo environmental enzyme,it can lower activation energy,accelerate biochemical reaction speed,form conformation inversion and induction wedge close with crude oil,electrical property functions and wedge close thing with crude oil,dredge the duct channel blocked;it also can lower fluid flow resistance of the strata,change surface wettability of the reservoir rock;enhancing liquidity of the crude oil etc. and we also analyze the oil displacement and dredging mechanism of Apollo environmental enzyme. 2011-03 http://en.cnki.com.cn/Article_en/CJFDTOTAL-DQGZ201103032.htm 

Experimental research on Bio-enzyme flooding in a low permeability reservoir

Zhu Jianhong,Pu Chunsheng,Tian Yang et al.Zhu Jianhong,School of Petroleum Engineering,Xian Shiyou University,Xian City,Shaanxi Province,710065,China   Yanchang oil field is a typical low permeability reservoir in Northern Shaanxi. The primary recovery is low with original formation energy and the water cut rises sharply during water flooding. The whole flooding recovery is poor. Bio-enzyme is an environmental clean and water-soluble agent. It can be injected into the formation pores effectively and alter the wettability of formation rock surface. The crude oil can be stimulated to fall off from the rock surface by reducing the residual oil saturation. And,the oil recovery will be enhanced. In this paper,the displacement efficiency of SUN compound Bioenzyme solution is evaluated in laboratory by one-dimension sand filled physical model flowing experiment. The results shows that the displacement efficiency of SUN compound Bio enzyme solution gets the best when its concentration is about 3% at the injected volume of 0.4PV.The displacement efficiency is increased by about 11.4% for low permeability core of Yanchang oil field. This indicates that the SUN compound Bio-enzyme oil displacement agent is suitable for low and ultra low permeability reservoir water flooding. http://en.cnki.com.cn/Article_en/CJFDTOTAL-YQCS201202013.htm

Application of enzyme treatment technique on Pucheng Oilfield

YANG Jianhua, SUO Yingzi,NAN Nan(Second Production Plant of Branch of Zhongyan Oilfield Co.,Ltd.,Fan Xian,Henan 457532,China)  Through implementation of bio-enzymatic technology,production wells on Pucheng Oilfield to see the effect of increasing oil well plugging,and achieved good economic and social benefits. http://en.cnki.com.cn/Article_en/CJFDTOTAL-HXQX201111006.htm

Environmentally friendly bio-enzyme displacement technology in Dagang Oilfield.

Zhao Dongyun. Zhao Dongyun,Technology Research Institute,The Fifth Oil Production Plant, Dagang Oilfield,Tianjin, 300280,China  In the middle and late period of oilfield development,the physical properties of underground crude oil is deterioration,and the reservoirs are subject to varying degrees of pollution and blockage because of various jobs and construction,which have a greater impact on normal production wells. Environmentally friendly bio-enzyme displacement technology can reduce formation damage,enhance oil recovery ratio with simple construction, easy operation,strong adaptability to the changes of temperature, pressure, pH and water salinity in different types of reservoirs,which is the inevitable choice for the tertiary oil recovery. In order to promote the environmentally friendly bio-enzyme displacement technology, the author analyzed its mechanism and characteristics of enhancing oil recovery and the applicable conditions for oil reservoirs,introduced the pilot field test of environmentally friendly bio-enzyme displacement technology in GX 41-22 Fault Block of Dagang Oilfield.The target horizon in GX 41-22 Fault Block with environmentally friendly bio-enzyme displacement was Nm Ⅱ 5-3 reservoir group, two slugs were injected by biological enzyme in total 16 t with solution 333 m3,the injection mass concentration:the first slug was 600 g / L, the second was 400 g / L.Among 5 benefit wells,four wells were effective and integrated water cut was dropped by an average of 14.7%,the cumulative increase in oil was 1923 t,thus achieving a better application effect. http://en.cnki.com.cn/Article_en/CJFDTOTAL-LJGZ201204021.htm

Screening and optimizing culture conditions of strains producing protease for bio-extraction

plug removal agent in petroleum

ZUO Jia-min1,HE Lian-fang1, ZHANG Yu-cang2, LIU Fei1(1.Research Institute of Resource Exploitation and Utilization,Dalian Polytechnic University, Dalian, Liaoning 116034,China;2.School of Chemistry and Material, Hainan University, Haikou, Hainan 570228,China)  Screening, re screening and optimizing culture conditions of bacterial strains producing protease was studied for biological enzyme plug removal agent in petroleum. Protease producing strains were screened from Daqing crude oil samples. Namely the use of hydrolyzed casein transparent circle experiment and forint phenol method of protease activity for screening and re screening strains. Then,to satisfy the size of protease activity indicator,by single factor test,the culture mediums and culture conditions of the strain were optimized. The strain that showed protease activity had grown well with soluble starch(15 g/L), peptone +yeast extract(20 g/L,20 g/L),NaCl(1.0 g/L),CaCl2(0.02 g/L),Na2HPO4(0.2 g/L),NaH2PO4(0.1 g/L),and the optimum culture conditions were initial pH(6.0),vaccination(5%),temperature(31 ℃),shaker speed(160 r/min),culture time(72 h).The activity of protease in the optimal conditions was up to 551.0 U/mL which was found to be 22.92 times more than that produced by the rescreened strains. At this time,the best condition that growth reproduction and metabolism of the strain and higher protease activity were obtained,which is favorable for conducting subsequent experiments. Protease produced by the strain have effects in reducing surface tension of fermentation liquid to crude oil,from 56.2 mN/m reduced to 30.5 mN/m,surface tension decreased significantly. What's more,it can play an important role in degrading crude oil and reducing viscosity,having certain research value. http://en.cnki.com.cn/Article_en/CJFDTOTAL-DQSY201202018.htm