In recent years,controlling the salinity and composition of the injected water has become an emerging enhanced oil recovery(EOR)technique,often described as low salinity(LS)waterflooding.This work is done with the int...In recent years,controlling the salinity and composition of the injected water has become an emerging enhanced oil recovery(EOR)technique,often described as low salinity(LS)waterflooding.This work is done with the intention to contribute to the ongoing discussions about LS waterflooding mechanism(s).For this purpose,a series of different experiments were conducted.At first,the effect of salinity on the interfacial tension(IFT)and the contact angle was evaluated with a crude oil sample.Then to achieve more accurate results in observing oil/water interface,similar IFT experiments were also carried out on a synthetic oil containing asphaltenes.Thereafter,microscopic visualization using glass micromodel was performed on the interface of the synthetic oil sample and brines.Four brine solutions including Sea Water(SW),it's dilutions and formation water(FW)were used for various experiments.Finally,to investigate the presented mechanism by other authors,a series of Environmental Scanning Electron Microscopy(ESEM)analysis on the synthetic oil was carried out to understand better the phase behaviour after contacting both synthetic oil and water phases from the micromodel experiment.Based on the existing mechanism,there exists an optimal concentration beyond which dilution is no longer an effective process.展开更多
Despite many efforts into the study of fluids interaction in low salinity water flooding, they are not probing the basics of transport phenomena between the involved phases. This work is aimed to bring new understandi...Despite many efforts into the study of fluids interaction in low salinity water flooding, they are not probing the basics of transport phenomena between the involved phases. This work is aimed to bring new understanding of fluid-fluid interaction during low salinity water flooding through a series of organized experiments in which a crude oil sample with known properties was kept in contact with different brine solutions of various ionic strengths. Measuring brine pH, conductivity and crude oil viscosity and density for a period of 45 days illustrates the strong effect of the contact time and ionic strength on the dissociation of polar components and physical properties of the crude oil and brine. Besides, the interfacial tension(IFT) measurements show that the interfacial interactions are affected by several competitive interfacial processes. By decreasing the ionic strength of the brine, the solubility of naphthenic acids in the aqueous solution increases, and hence,the conductivity and the pH of the aqueous phase decrease. To verify this important finding, UV-Vis spectroscopy and 'H NMR analysis were also performed on aged brine samples. Notably, there is an ionic strength of brine in which the lowest IFT is observed, while the other physical properties are remained relatively unchanged.展开更多
AI（OH）3 was prepared to extract lithium ions from calcium chloride-type oil field brine. The influences of four factors, namely temperature, Al3＋/Li＋ molar ratio, OH-/Al3＋ molar ratio, and contact time between AI...AI（OH）3 was prepared to extract lithium ions from calcium chloride-type oil field brine. The influences of four factors, namely temperature, Al3＋/Li＋ molar ratio, OH-/Al3＋ molar ratio, and contact time between AI（OH）3 and the brine, on the yield of lithium ions were investigated. It is found that their optimal values are 35℃, 4.5, 2.6, and 6 h, respectively. In the course of the experiment, the apparent pH value was observed. The results reveal that the apparent pH value has no remarkable influence on the yield of lithium ions. Meanwhile, the effects of the concentrations of calcium ions and magnesium ions in the brine on lithium recovery were studied. The results indicate that cal- cium ions have minor negative influence on the yield of lithium ions under optimal conditions, and magnesium ions slightly influence the yield of lithium ions.展开更多
The e ects of CO2 and salt type on the interfacial tension(IFT) between crude oil and carbonated brine(CB) have not been fully understood. This study focuses on measuring the dynamic IFT between acidic crude oil with ...The e ects of CO2 and salt type on the interfacial tension(IFT) between crude oil and carbonated brine(CB) have not been fully understood. This study focuses on measuring the dynamic IFT between acidic crude oil with a total acid number of 1.5 mg KOH/g and fully CO2-saturated aqueous solutions consisting of 15,000 ppm of KCl, NaCl, CaCl2 and MgCl2 at 30 °C and a wide range of pressures(500–4000 psi). The results of IFT measurements showed that solvation of CO2 into all the studied aqueous solutions led to an increase in IFT of acidic crude oil(i.e., comparison of IFT of crude oil/CB and crude oil/brine), while no significant e ect was observed for pressure. In contrast, the obtained results of studied salts indicated a positive e ect on the IFT reduction of acidic crude oil/carbonated water(CW)(i.e., comparison of IFT of crude oil/CB and crude oil/CW).展开更多
Based on adhesion models between rock surface groups and organic molecules,the interactions between the chemical groups on the rock surface and the components of crude oil and the interactions of the electrical double...Based on adhesion models between rock surface groups and organic molecules,the interactions between the chemical groups on the rock surface and the components of crude oil and the interactions of the electrical double layers at the rock surface and oil-water interface were analyzed to investigate the abilities and microscopic mechanisms of wettability control by H^+,OH^- and inorganic salt ions in brine,and a new method of wettability control for reservoir rocks was built.The results show that the interaction forces between rock surface groups and oil molecules are van der Waals forces,Coulomb forces,hydrogen bonds,and surface forces.By changing these forces,the control mechanisms of surface wettability of reservoir rocks by brine are:transformation of chemical groups,change of interfacial potential,pH variation of injected water,multicomponent ionic exchange,and salting-in or salting-out effect.For sandstone reservoirs,with the decrease of concentration and valence state of positive ions in brine or the increase of pH(increasing pH has a negligible impact on the brine salinity),the interaction between rock surface and oil becomes weak,thus resulting in increase of water wettability of rock surface.For carbonate reservoirs,CaSO_4 or MgSO_4 brine with high concentration is beneficial to increase water wettability of rock surface.Therefore,it is feasible to control rock wettability and improve oil recovery by adjusting the ion components of injected water.展开更多
以辛烯基琥珀酸淀粉钠和麦芽糊精为复合壁材对精炼过后的鸡油进行喷雾制作微胶囊鸡油。通过响应面分析法获得最佳微胶囊制作工艺条件为进风温度190℃、均质压力39 MPa、进样速率15 m L/min,最终微胶囊鸡油产品包埋率为95.9%。微胶囊鸡...以辛烯基琥珀酸淀粉钠和麦芽糊精为复合壁材对精炼过后的鸡油进行喷雾制作微胶囊鸡油。通过响应面分析法获得最佳微胶囊制作工艺条件为进风温度190℃、均质压力39 MPa、进样速率15 m L/min,最终微胶囊鸡油产品包埋率为95.9%。微胶囊鸡油呈规则球状,表明较光滑,减少了与外界接触的机会,减慢了氧化速率。产品经(60±1)℃加速氧化5 d后,过氧化值仅为对照样品的1/3,抗氧化效果明显。展开更多
文摘In recent years,controlling the salinity and composition of the injected water has become an emerging enhanced oil recovery(EOR)technique,often described as low salinity(LS)waterflooding.This work is done with the intention to contribute to the ongoing discussions about LS waterflooding mechanism(s).For this purpose,a series of different experiments were conducted.At first,the effect of salinity on the interfacial tension(IFT)and the contact angle was evaluated with a crude oil sample.Then to achieve more accurate results in observing oil/water interface,similar IFT experiments were also carried out on a synthetic oil containing asphaltenes.Thereafter,microscopic visualization using glass micromodel was performed on the interface of the synthetic oil sample and brines.Four brine solutions including Sea Water(SW),it's dilutions and formation water(FW)were used for various experiments.Finally,to investigate the presented mechanism by other authors,a series of Environmental Scanning Electron Microscopy(ESEM)analysis on the synthetic oil was carried out to understand better the phase behaviour after contacting both synthetic oil and water phases from the micromodel experiment.Based on the existing mechanism,there exists an optimal concentration beyond which dilution is no longer an effective process.
基金supported by Iranian Offshore Oil Company (IOOC)
文摘Despite many efforts into the study of fluids interaction in low salinity water flooding, they are not probing the basics of transport phenomena between the involved phases. This work is aimed to bring new understanding of fluid-fluid interaction during low salinity water flooding through a series of organized experiments in which a crude oil sample with known properties was kept in contact with different brine solutions of various ionic strengths. Measuring brine pH, conductivity and crude oil viscosity and density for a period of 45 days illustrates the strong effect of the contact time and ionic strength on the dissociation of polar components and physical properties of the crude oil and brine. Besides, the interfacial tension(IFT) measurements show that the interfacial interactions are affected by several competitive interfacial processes. By decreasing the ionic strength of the brine, the solubility of naphthenic acids in the aqueous solution increases, and hence,the conductivity and the pH of the aqueous phase decrease. To verify this important finding, UV-Vis spectroscopy and 'H NMR analysis were also performed on aged brine samples. Notably, there is an ionic strength of brine in which the lowest IFT is observed, while the other physical properties are remained relatively unchanged.
基金supported by the Ministry of Science and Technology of People's Republic of China (No.2006BAB09B07)National Nature Science Foundation of China (No.41073023)Research Project of Science and Technology Department of Qinghai Province, China (No.2010-G-210)
文摘AI（OH）3 was prepared to extract lithium ions from calcium chloride-type oil field brine. The influences of four factors, namely temperature, Al3＋/Li＋ molar ratio, OH-/Al3＋ molar ratio, and contact time between AI（OH）3 and the brine, on the yield of lithium ions were investigated. It is found that their optimal values are 35℃, 4.5, 2.6, and 6 h, respectively. In the course of the experiment, the apparent pH value was observed. The results reveal that the apparent pH value has no remarkable influence on the yield of lithium ions. Meanwhile, the effects of the concentrations of calcium ions and magnesium ions in the brine on lithium recovery were studied. The results indicate that cal- cium ions have minor negative influence on the yield of lithium ions under optimal conditions, and magnesium ions slightly influence the yield of lithium ions.
文摘The e ects of CO2 and salt type on the interfacial tension(IFT) between crude oil and carbonated brine(CB) have not been fully understood. This study focuses on measuring the dynamic IFT between acidic crude oil with a total acid number of 1.5 mg KOH/g and fully CO2-saturated aqueous solutions consisting of 15,000 ppm of KCl, NaCl, CaCl2 and MgCl2 at 30 °C and a wide range of pressures(500–4000 psi). The results of IFT measurements showed that solvation of CO2 into all the studied aqueous solutions led to an increase in IFT of acidic crude oil(i.e., comparison of IFT of crude oil/CB and crude oil/brine), while no significant e ect was observed for pressure. In contrast, the obtained results of studied salts indicated a positive e ect on the IFT reduction of acidic crude oil/carbonated water(CW)(i.e., comparison of IFT of crude oil/CB and crude oil/CW).
基金Supported by China National Science and Technology Major Project(2017ZX05009-004)the National Natural Science Foundation of China(51274211)
文摘Based on adhesion models between rock surface groups and organic molecules,the interactions between the chemical groups on the rock surface and the components of crude oil and the interactions of the electrical double layers at the rock surface and oil-water interface were analyzed to investigate the abilities and microscopic mechanisms of wettability control by H^+,OH^- and inorganic salt ions in brine,and a new method of wettability control for reservoir rocks was built.The results show that the interaction forces between rock surface groups and oil molecules are van der Waals forces,Coulomb forces,hydrogen bonds,and surface forces.By changing these forces,the control mechanisms of surface wettability of reservoir rocks by brine are:transformation of chemical groups,change of interfacial potential,pH variation of injected water,multicomponent ionic exchange,and salting-in or salting-out effect.For sandstone reservoirs,with the decrease of concentration and valence state of positive ions in brine or the increase of pH(increasing pH has a negligible impact on the brine salinity),the interaction between rock surface and oil becomes weak,thus resulting in increase of water wettability of rock surface.For carbonate reservoirs,CaSO_4 or MgSO_4 brine with high concentration is beneficial to increase water wettability of rock surface.Therefore,it is feasible to control rock wettability and improve oil recovery by adjusting the ion components of injected water.
文摘以辛烯基琥珀酸淀粉钠和麦芽糊精为复合壁材对精炼过后的鸡油进行喷雾制作微胶囊鸡油。通过响应面分析法获得最佳微胶囊制作工艺条件为进风温度190℃、均质压力39 MPa、进样速率15 m L/min,最终微胶囊鸡油产品包埋率为95.9%。微胶囊鸡油呈规则球状,表明较光滑,减少了与外界接触的机会,减慢了氧化速率。产品经(60±1)℃加速氧化5 d后,过氧化值仅为对照样品的1/3,抗氧化效果明显。
