Abstract:The drilling fluids loss reduction additive JLS-2 was synthesized by the polymeration of anti-temperature and anti-salt monomer(AMPS),acrylamide(AM),cationic monomer dimethyl diallylammonium chloride(DMDAAC) as a cationic monomer and an ester monomer(BXZ).Using API water loss as evaluation index,single factor experiments were carried out and the optimal synthesis conditions was obtained as follows,the ratio of monomer AM,AMPS,DMDAAC and BXZ was 40∶ 40∶ 5∶ 2,the total mass fraction of monomers was 20%,the amount of initiating agent was 0.30%,the reaction temperature was 70℃,the reaction time was 50 min.Infrared spectrum analysis proved that the structure of the synthesized production was identified with the original design.The performance evaluation experiments results indicated that filtration control agent JLS-2 had good capacity in depressing filtrate loss and heat resistance to 120℃,after adding 1.0% and 2.5% JSLS-2,respectively,the API water loss of freshwater mud and composite salt mud were 6.1 mL and 9.3 mL,respectively.

Abstract:Aimed at the outstanding problem of adjustment of filtration property and high temperature stability of high temperature water-based drilling fluid at home and abroad,the anti 240 ℃ and salt tolerant polymeric filtrate loss reducer HTP-1 was developed based on optimum design of molecular structure and selection of monomer.The optimum synthesis conditions of HTP-1 was as follows: pH value was 7.0,the mass ratio of DEAM,AMPS,NVP,DMDACC was 6∶ 3∶ 3∶ 1,the initiator content was 0.1%,reaction temperature was 60℃ and reaction time was 4 h.the result of thermal gravitational analysis showed that the thermal decomposition onset temperature of HTP-1 was up to 320℃,indicating that HTP-1 possessed strong thermal stability.The experiments of calcium and salt tolerance showed that performance of HTP-1 in drilling fluid containing 267 g/L salt or 5 g/L calcium chloride was stable,which was similar to that of the foreign anti high temperature polymer Driscal and superior to domestic metallic ion fluid loss additive PMHA-Ⅱ.The filtration reducing ability of HTP-1 at high temperature of 240℃ was better than that of Driscal(240℃) and domestic PMHA-Ⅱ(220℃) in fresh water drilling fluid,weighted fresh water drilling fluid,saturated brine drilling fluid and compound salt water drilling fluid,respectively.In the end,the mechanisms of heat and salinity tolerance and filtrate loss reduction of HTP-1 were probed.

Abstract:PFL series polymer filtrate reducer is characterized of low viscosity,good capacities of depressing the filter loss,heat resistance and salt tolerance.The apparent viscosity of 1% PFL-L aqueous solution and 1% PFL-H aqueous solution were 12 mPa · s and 26 mPa · s,respectively.After aging at 240℃/16 h,with the addition of 5%PFL-L,the filer loss(FL) of the saturated salt water mud(SSWM),composed of 4% bentonite and 36% NaCl,decreased from 226 mL(blank group) to 32 mL;with the addition of 4%PFL-H,the FL of the SSWM decreased from 226 mL(blank group)to 8.2 mL;with the addition of 1.5% PFL-H,the FL of fresh water mud,composed of 4% bentonite,decreased from 100 mL(blank goup)to 9.6 mL.Based on the PFL series ultra-high temperature polymer filtrate reducer and the optimized sulfonating filtrate reducer,inhibitor,lubricant,thinner,the strong inhibited brine and fresh drilling fluids,which were heat resistant to 200℃,were formed.The field application manifested that the PFL series ultra-high temperature polymer filtrate reducer showed strong heat resistance and good capacities of depressing the filter loss,making sure that the Xuwen X3 well was drilled to 6010 m and the logging temperature of 211℃ at the depth 5974 m.

Abstract:The formula of high temperature tolerant and solids free weak gelling drilling fluid was: seawater,0.5% NaOH,0.5% Na2CO3,1% VIS-H,0.5% high temperature stabilizer SPD,3% KCl,1% polyamine UHIB,3% polymerization alcohols JLX-C,3% fluid loss agent RS-1 and 5% acid-soluble reservoir protection agent JQWY.The density of drilling fluid was aggravated to 1.2 g/cm3by sodium formate.The results of property evaluation showed that the high temperature stability of drilling fluid was good and the viscosity was of 34095 mPa · s with low rotate speed 0.3 r/min after rolling 16 h at 160℃.The lubricity and inhibitory of drilling fluid was good with 0.083 adhesion coefficient at 90℃,90.28% rolling recovery rate and 90.59% anti-clay-swelling rate.The damage of drilling fluid to reservoir greatly reduced after reservoir protective agent JQWY added and API filtration decreased to 2.6 mL.The filter cake could be easily removed by breaking gel agent JPC-LV on completion and the core recovery of permeability reached 97.8% which met the requirements of hydrocarbon reservoir development in high temperature horizontal well.

Abstract:采用XRD、ESEM-EDX和TG-DSC测试分析方法，对泥饼固化提高固井二界面胶结强度的机理进行了研究。结果表明，泥饼固化法制备的固井二界面凝饼中生成了水化硅酸钙（C-S-H）凝胶和沸石类凝胶。它们是由泥饼改性剂中的活性物质、黏土矿物被溶蚀析出的活性物质、水泥水化产生的水化离子和凝饼形成剂共同作用形成的。这些胶凝物质填充在黏土矿物和钻井岩屑之间，并将之粘接在一起，相互胶结形成了连续相，实现了固井二界面的整体固化胶结。图7表1参12

Abstract:以低失水量、低稠度系数（K）为目标。根据自由基聚合的原理，利用正交实验的方法，以2．丙烯酰胺基-2．甲基丙磺酸（AMPS）、丙烯酰胺（AM）、N，N-二甲基丙烯酰胺（NNDMA）和有机羧酸（DS）为反应单体，合成了一种耐高温油井水泥降失水剂。最佳合成条件为：单体AMPS、AM、NNDMA、DS摩尔比4：2．5：2．5：1，单体加量32．5％，引发剂加量1．0％，pH值4，温度40℃。该条件下产物的水泥浆足值为O．041Pa·s，失水量31mL。测试结果表明，降失水剂加量增加，水泥浆K值增加，失水量降低。降失水剂加量为2％时的x为0．361Pa·s，水泥浆流变性较好。在NaCI加量为30％、降失水剂加量为2％时，水泥浆失水量为31mL，耐盐性较好。随温度升高，水泥浆失水量增加，稠化时间缩短，无“倒挂”现象。120℃和150℃下，含1％降失水剂水泥浆的失水量分别为36mL／30min和59mL／30min，耐温能力较好。图5表1参11

Abstract:在大庆外围埋藏浅、储层温度低的朝98区块葡萄花储层水平井的压裂改造中，如何实现压裂液在30℃储层中压后破胶并快速返排，是确保施工成功和提高压后效果的关键。室内研制了由0．6％稠化剂SG、1％岩石稳定剂CYDF、0．3％高效助排剂JX-YL、0．2％三元破胶剂、3％硼砂交联剂组成的超低温压裂液体系。在30℃、170s。下，压裂液冻胶剪切5min后的黏度基本稳定，约为140mPa·8，抗剪切性较好。该压裂液破胶快速、彻底，30℃破胶4h后的黏度为3．5mPa·s。JX-YL减小了压裂液的滤失，降低了储层伤害。加入JX—YL后，压裂液滤失量比未加JX-YL的减少17．2％。压裂液具有配制方便、破胶性能良好的特点。在8口超浅层水平井开展现场压裂试验，应用效果良好，满足低温井（浅井）油层水平井压裂改造的需要。图3表4参8

Abstract:在普通胍胶中加入悬浮稳定剂、醇类助剂、表面活性剂类胶体组成了相对稳定的速溶胍胶，其含水率为3．42％，水不溶物含量为8．76％。考察了影响压裂液质量的主要因素及由速溶胍胶配制压裂液的性能。实验结果表明：基液的起黏速度随搅拌速度增大而加快，1000r／min下搅拌5rain时，基液黏度达到最终黏度的90％；最佳配液水温在10℃左右；最佳配液pH值为6；KCl的加入减缓了胶液的起黏速度，但最终黏度随KCl加量增大而升高。与硼交联后的冻胶体系的黏弹性增加，且在较高振荡频率时，G’〉G″，在频率为1Hz时，储能模量G′和损耗模量G″分别为9．8Pa和8．8Pa，可满足携砂性能。该冻胶体系的滤失系数G=2．65×10-4m／min1/2。，滤失速率Vo=0．44X10～m／min，具有较小的滤失量；在110℃、0．10％破胶剂条件下，24h后破胶液的黏度小于2mPa·S；对岩心的平均伤害率为11．24％。与常规配液方式相比，单井可节约胍胶15％以上，具有广阔的应用前景。图6参1

Abstract:聚乙酸乙烯酯的醇解度显著影响其性能和运用，本文研究了NaOH／PVAc摩尔比、NaOH浓度、PVAc聚合液浓度、反应温度和反应时间对聚乙酸乙烯酯醇解反应的影响。研究结果表明，影响醇解度最重要的因素是彬PYAc摩尔比，其次是反应时间，碱/CPVAc摩尔比和反应时间有协同作用，反应温度是反应中的次要影响因子。结合均匀设计方法，优化PVAc醇解工艺，提出了以控制碱/YCPVAc摩尔比和反应时间达到调控PVA醇解度的稳定控制方法。图8表4参4

Abstract:Organic-inorganic crosslinked plugging system was prepared with resin prepolymer CL,silicide and stabilizer SY.The microstructure of the gelling system observed by ESEM showed that there existed the network structure.The optimal formula of the system at 130℃ CL was obtained through lab test,and the appropriate mass fraction of resin prepolymer was 4%7%,the silicide was 1%5% and the stabilizer SY was 0.1%0.3%.Evaluation test of thermal stability showed that the plugging agent was resistant to the high temperature of 140℃,and it’s gelation time at 130℃ was adjustable from 2 to 24 hours,and which could be prolonged to 50 hours at least when the temperature was reduced to 110℃.The change of apparent viscosity during the gelling process showed that the injectivity was good.The core modeling experiment indicated the plugging rate of the agent could reach over 98.5%;moreover,it had nice performance of flushing resistance.

Abstract:The cross-linked polymer microspheres was synthesized by the methods of inverse emulsion polymerization,and the microspheres morphology,compatibility,sealing and oil properties of the dispersed system were studied.The results of SEM and TEM showed that the diameter of microspheres was in range of 100—200 nm after soaked with water for 10 d.Moreover,the cross-linked polymer microspheres possessed good salt tolerance and could plug the millipore filtration effectively.The results of block experiment in the sand tube with the multi-point manometry showed that the cross-linked polymer microspheres system could flow into the deep sand tube and play an effective role in blocking.The oil displacement experiments on parallel sand cores showed that after injecting 3 PV crosslinked polymer microspheres system with the mass fraction of 0.04%,prepared with oilfield simulation water,the oil recovery of the high,low permeability core with gas permeability of 2.0 μm2 and 0.5 μm2,respectively,could be enhanced by 21.42% and 42.69% based on the water flooding(61.61% and 0),respectively.

Abstract:in order to evaluate the feasibility of water flooding for the 3rd member of Shahejie formation in block-Qu 9-21,a series of concerned experiments were carried out,such as reservoir petrophysical properties analysis,static compatibility evaluation between source water and formation water,formation sensitivity analysis and dynamic compatibility evaluation between source water and formation.In addition,the damage mechanism of water flooding process was analyzed and the quality index of the injected water was established by means of laboratory water flooding tests.It was shown that permeability retention rate was low to 29.4% when core had been more seriously damaged from water flooding of long duration by untreated field source water.It was concluded that the higher salinity of the injected water than formation water and the mechanical impurities of the injected water were key factors influencing water flooding development.Hence,in order to remove formation damage,the reduction of the content of mechanical impurities of the injected water was a major measure taken.According to test results,the recommended mechanical impurities index of the injected water for the third member of Shahejie formation in block-Qu 9-21 is grade B2.

Abstract:Nano-polysilicon dispersible in water was synthesized and resultant nano-polysilicon was used for decompression and augmented injection of the water-injection wells in low-permeability reservoir with water as a replacement carrier of organic dispersant.Based on the analysis of pore-throat characteristics in Baolang reservoir,it was suggested that the size of nano-polysilicon should be 10—20 nm so as to well match with the size of pore-throat.Besides,the nano-polysilicon emulsion was transparent.Through the study of dispersion capacity and stability of the emulsion,the formula of nano-polysilicon water-based decompression and augmented injection fluid was: 1.75 ‰ nano-polysilicon and 2‰ assistant dispersant.After being treated with nano-polysilicon water-based emulsion,it was feasible to convert the hydrophilic core surface into a great hydrophobic with contact angle increasing from 23.7° to 131.8°.Core flow tests showed that the water permeability increased by 40% in average after being treated with this fluid.For sewage injection well and water injection well changed from oil well,it was supposed that an excellent decompression and augmented injection effectiveness could be achieved when pre-acidizing was done before nano-liquid augmented injection.Field test in Baolang oilfield indicated that the title augmented injection agent was able to increase the augmented injection effectiveness by a rate of 80% and could retain effectiveness in more than one year.

Abstract:In this paper,in view of the properties of reservoir and oil in KMK oilfield of Kazakhstan,the major factors influencing the reaction process,including the concentration of the initiator and the initial temperature,were researched through the laboratory experiments,and the effects of thermo-chemical reaction on the viscosity reduction of the KMK crude oil were evaluated.The results showed that,the higher the concentration of initiator was,the faster the reaction velocity was and the higher the peak temperature was;the higher the initial temperature was,the more the gas volume was.In the pretreatment section,the heat released from the system reaction could reduce the viscosity of the crude oil and dissolve the organic substances to improve the oil flowability and enhance the oil recovery.The results of the simulation experiments indicated that significant effects in KMK oilfield would be achieved by adopting the heavy oil thermo-chemical production technology.

Abstract:A hydrophobically associating polyacrylamide(HAPAM) with a certain hydrolysis degree(25%) had been synthesized by copolymerization of acrylamide,sodium acrylate and hydrophobic monomer.The higher hydrolysis degrees of polymer were obtained through hydrolysis reaction by sodium hydroxide under high temperature of 95℃.The effects of the hydrolysis degree,salinity,and shear rate on the viscosity of hydrophobically associating polymer were investigated in aqueous solution.The experiment results showed that the apparent viscosity of the polymer solution increased first and then decreased with increasing hydrolysis degree.It was observed that the viscosity was greatly affected by the salt concentration and obvious phase separation occured in the polymer solution when the hydrolysis degree was higher than 50% at high Ca2+ and Mg2+ concentration.Under the experimental shear rate,the viscosity behaviors of HAPAM showed shear thinning.The polymer solution exhibited remarkable viscoelasticity at lower hydrolysis degree,however,the polymer solution only appeared viscosity when the hydrolysis degree exceeds to a certain extent.For the same polymer,there was a maximum of the viscoelasticity of the solution with the increasing of the NaCl concentration.

Abstract:Hydrophobically associating anionic terpolymer(PAtBS) was synthesized by free micellar copolymerization of acrylamide(AM),4-tert-butylstyrene(tBS) and sodium 4-vinylbenzenesulfonate(SSS).The copolymer structure was identified by FTIR,UV,and 1H-NMR.Furtherly,the aqueous solution properties of the copolymer were investigated by rotary viscometer.The results showed that the content of the monomer structural units in the copolymer coincided approximately with its feed ratio.The increasing viscosity ability of PAtBS in sodium chloride or calcium chloride aqueous solution is stronger than that of partially hydrolyzed polyacrylamide with molecular weight of 1.97×107 and hydrolysis degree of 19.43%.The viscosity of polymer aqueous solution declined slightly with the increase of temperature when the temperature was above 50℃,which indicated that the synthesized copolymer had good performance of salt and temperature resistance.

Abstract:Allowing for the actual demands of the oilfields,the performance of the viscosity,salt tolerance,temperature resistance,time stability,molecular coil dimension,molecular aggregation,rheological property,viscoelasticity and flow characteristics of the HPAM/layered silcated nanocomposite(PLSN) solution was evaluated by modern reservoir engineering theory,equipment analysis and the physical simulation.The results showed that,the PLSN had an excellent salt tolerance,temperature resistance and time stability compared to the common polymer including "salt tolerance" polymer and "high molecule weight" polymer.The aggregation of PLSN was mainly a "flaky-reticular" formation while the "high molecule weight" HPAM had an elongated chain reticular configuration.Furthermore,oil displacement efficiency of PLSN would be higher than that of the common polymer because of its excellent viscoelasticity.Core flooding tests results indicated that,compared with common polymer,the PLSN material was characterized of lower viscosity and higher resistance factor and residual resistance factor,which ensured that the PLSN solution had a good fluid diverting role.

Abstract:Nanbao 35-2 was characteristic of the high viscosity,high permeability,serious heterogeneity,etc.During water flooding process,because of the serious fingering phenomenon,it was difficult to obtain high water fllooding recovery.In the paper,the profile control agents were optimized by the methods of the instrument testing and core flooding tests.And then the average concentration and slug size were optimized by using the BP neural network prediction method based on core flooding parameters sample and economic evaluation.Compared with laboratory analysis data and optimization results,for A21 well,the best slug size and average concentration were 0.1 PV and 2200 mg/L,respectively.During the profile control process,injection pressure increased significantly.In the case without considering the natural decline rate,the oil wells incremental oil production was 27639.59 m3.The measurements achieved an obvious oil increment and water reduction.And economic benefits are very obvious.

Abstract:The dynamic interfacial tension between Daqing oil and alkanolamide surfactant system(Cn(m+m)) was measured and the effect of carbon chain length(n) and hydrophilic groups(m) was studied.Experiment results showed that the interfacial tension of alkanolamide surfactant with the same n increased gradually when m changed from 1 to 3.When the number of hydrophilic groups was of 1,the interfacial tension of alkanolamide surfactant did not decrease with increasing carbon numbers.While m was of 2 or 3,the interfacial tension decreased with increasing n.The interfacial activities of different series alkanolamide surfactants were deeply researched by organic concept map.And the ratio of hydrophilicity to lipophilicity(I/O value) of the surfactants was calculated.Based on the organic concept diagram theory,the more access to zero the |I/O-1| value,the better interfacial activities of alkanolamide surfactants.The |I/O-1| value of C16(1+1),C14(1+1),C18(1+1),C12(1+1) was of 0.03,0.09,0.13,0.25,respectively.That of C16(1+1) was closest to zero,and that of C14(1+1),C18(1+1) and C12(1+1) increased by sequence.The values of calculation were consistent with that of the determination.Therefore,under the condition of the same n,the |I/O-1| value of surfactants in the organic concept diagram would deviate away zero with increasing m,which reflected the worse interfacial activities of the surfactants.

Abstract:In this paper,the surface activity of carboxylate gemini surfactants CGS-2 and the effect of the addition of NaCl on it were investigated,the effects of the liquid-solid ratio,absorption time and concentration on the surface adsorption of CGS-2 on the sandstone were studied.The results showed that,the critical micelle concentration of CGS-2 solution was 0.0223 mmol/L,which was 2—3 magnitude orders lower than that of the conventional surfactants,laurate sodium.The surface tension minimized to 29.49 mN/m.When adding a given mass of NaCl,the critical micelle concentration of CGS-2 decreased.The adsorption isotherm accorded with Langmuir mode.When the Liquid-solid ratio was 30∶ 1,and the adsorption equilibrium time was 36 h,the adsorption capacity of CGS-2 reached to the maximum on the sandstone surface at 25℃,being of 8.93 mg/g.

Abstract:The block of Zhuang 115 in the Zhuangxi oil production plant of Shengli oilfield was characteristic of high temperature and middle-low permeability.In order to improve the effect of injection and production,surfactant flooding was proposed.The interfacial tension between betaine surfactant solutions and the crude oil of Zhuang 115,and the adsorption of betaine surfactant on the surface of the qaurts sand,was investigated,as a result,a low interfacial tension displacement system with betaine surfactant as the main agent and sodium humate as the sacrificial agent was developed.The adsorption amount of the system on the surface of quarts sand was 0.4 mg/g,and the interfacial tension between the system and the crude oil was low to 5×10-3 mN/m without the help of alkali.Physical simulation experiments indicated that the oil recovery was enhanced by 17%,based on oil recovery of 53.6% of water flooding,when a slug of 0.3 PV water shutoff agent and 0.3 PV surfactant displacement system were used.This technique had been used in Zhuang 115-5 well in January 2008,and until May 2010,the net output of oil was increased by 1632 tons.

Abstract:The oil displacement properties of an environment friendly surfactant named YCH-601 and its combination system were studied.Biological toxicity evaluation test showed that YCH-601 had no toxicity,no skin irritation and no allergic reaction.The laboratory experiment results showed that YCH-601 had a better emulsifying capability to crude oil than that of usual surfactants used in oilfield.And the absorption of YCH-601 on the surface of sandstones was lower with a sustained dynamic absorption of 0.123 mg/g sand.Compared with other surfactants,surface tension reducing effect of YCH-601 was the best with the lowest working concentration,whose lowest surface tension was of 26.7 mN/m.Its combination systems of AON and ASN,which could reduce surface tension effectively,provided high resistance to Na+ which concentration was of 20 g/L and 50 g/L respectively,and that to Ca2+ was of 1500 mg/L and 4000 mg/L respectively.Moreover,after treated with high temperature of 150℃,both systems could still reduce the oil-water interfacial tension to the order of 10-3 mN/m.Both YCH-601 and its combination systems could enhance the oil recovery better that other surfactants,and the enhanced oil recovery was as high as 22.5%.

Abstract:according to the need of enhancement of oil recovery after polymer flooding,the multiple profile control and displacement system combined by gel microsphere,cross-linking agent and high effective displacement agent was screened,and the profile control displacement experiments after polymer flooding were carried out by injecting the single system,namely,50 mg/L(or 100 mg/L)cross-linking agent or 2000 mg/L cationic gel microspheres,binary system,composed of 100 mg/L cationic gel microspheres and 2000 mg/L cross-linking agent,and ternary system,composed of 0.4 PV×2000 mg/L gel microsphere,0.3 PV×100 mg/L cross-linking agent and 0.4 PV×2000 mg/L high effective displacement.The results showed that,when the injection volume was 1 PV,the binary injection system was better than single injection system.The injection breakthrough pressure showed a marked increase after binary system injection,being of about 3 MPa,which indicated that the binary system could effectively block the medium and high permeability pore by using the residual polymer in the core.The enhancement of oil recovery of the ternary system was 22.82% based on the water flooding,oil recovery being of 39.65%,and polymer flooding,enhancement of oil recovery being 18.38%.The injecting pressure during water flooding and polymer flooding was lower;with the injection of the ternary system,the pressure increased rapidly;and the pressure remained at range of 2 MPa during the following water injection,which was lower than that of the binary system.As a result,the injection of the ternary system after polymer flooding could not only block the high permeable layers and channels,but also take full use of medium and low permeability layers.

Abstract:A long core physical simulation system(800 cm) was applied to study the indigenous microorganism flooding on a block of Xinjiang Oilfield.Tracking measurement was investigated on the variation of microorganism,nutrition and metabolite.The activation result was different at different position which could be approximately divided into three parts,such as oxygen-enriched part,oxygen-lacked part and anaerobic part.The results showed that the cell population of aerobic bacteria was different at different position in the porous medium and that of the aerobic position was obviously higher than that of anaerobic position.There was no regularity about the surface tension at different sample points,and the measured value had ups and downs.The surface tension of culture medium reduced from 57.7 mN/m to the lowest value 41.51 mN/m.The cell population,total content of organic carbon and total content of nitrogen increased first and then decreased with increasing output of produced fluids.The cell population of probiotics had a large scale enhancement,and that of the sulfate-reducing bacteria was inhibited efficiently.The ultimate recovery increased by 5.84% OOIP.The indigenous microorganism was activated efficiently in simulated oil-bearing formation,and the results reflected the succession from aerobic to anaerobic microorganism in reservoir,which indicated that the flooding effect and development prospect of enhanced oil recovery employing indigenous microorganism was good.

Abstract:The red brown CHJ serial corrosion inhibitors were developed to resolve the corrosion of gas-gathering line system of high sulfur content gas well with high H2S/CO2 partial pressure and sulphur.CHJ corrosion inhibitors were composed of different amount of quaternary ammonium imidazoline,derivatives of thiazole and additives.The corrosion experiments were conducted under simulated condition of Puguang gas well.The corrosion rate was higher than 0.08 mm/a when CHJ-1 and CHJ-7 were injected respectively,while other five corrosion inhibitors could control the corrosion rate under 0.076 mm/a.The corrosion rate of CHJ-4 and CHJ-5 were 0.046 and 0.038 mm/a,and their inhibitory efficiency were of 92.6% and 93.9%,respectively.The corrosion rate were of 0.038、0.025 and 0.058 mm/a respectively when CHJ-4、CHJ-5 and foreign corrosion inhibitor were injected with separate and compound injection modes.The effect of CHJ serial corrosion inhibitors was obviously better.The microstructure analysis of test specimen and the electrochemical test results showed that the corrosion inhibitor played an important role on surface protection of the samples.In addition,the compatibility was good between corrosion inhibitors and sulphur-soluble reagent used on site.

Abstract:The effects of cationic polymer concentration,cationic degree,and molecular structure on oily sewage treatment in the polymer flooding oilfield were investigated by the measurement of zeta potential,turbidity,particle size,filtration time,etc..The results showed that zeta potential of sewage without HPAM residue was reversed by addition of small amount of cationic polymer,and the oil droplets possessed stable dispersion.HPAM as EOR residue was beneficial to the stable dispersion of oil droplets in sewage.After treated with cationic polymer,zeta potential,increasing extent of particle size and turbidity of sewage with HPAM residue decreased with the increase of the cationic polymer dosage and cationic degree.The optimum dosage of cationic polymer with cationic degree ≥15%,decreased with the increase of the cationic degree.The degreasing efficiency of cross-linked polymer was better than that of linear polymer.After treated with cross-linked polymer,the filtration time of sewage with HPAM residue was shorter.

Abstract:In order to simple,rapid and reliable determine the effect of surfactants on the oil/water interfacial tension,a set of apparatus which could rapidly determine interfacial tension of oil/water was built according to the rule of drop volume method.Influential factor,parallelization and reliability of determination results were examined.Experiment results showed that dripping speed had a big impact on the result of determination,which should be greater than or equal to five seconds each drop.Parallelization of the way was good,and the relative error was less than 2%.The determination error of benzene/water system was less than 1%,which indicated that this method could be used to determine the interfacial tension of the oil/water system.The effects of biological surfactant,rhamnoilpid industrial and chemical paraffin inhibitor on interfacial tension of crude oil/water were investigated by the way.The optimal dosage of three inhibitors were of 5%,4%,4%,respectively.Three drugs were arranged according to their influence on interfacial tension at the same dosage in following order: chemical paraffin inhibitor>biological surfactant>rhamnoilpid industrial.

Abstract:In this paper,the requirements of chemical water plugging in high temperature and high salt reservoir and the modified method of the ordinary plugging agents were probed,and the research advances and the field application of the high temperature resistant and high salinity tolerant plugging agents was reviewed,including polymer gel,preformed gel particles,salt precipitation and polymer microsphere,which are appropriate for high temperature and high salinity reservoir.In addition,the problems still existing in research and application were mentioned.