The processes of flooding—water flooding, polymer flooding and ternary combination flooding—were simulated respectively on a 2-D positive rhythm profile geological model by using the ASP numerical modeling softw...The processes of flooding—water flooding, polymer flooding and ternary combination flooding—were simulated respectively on a 2-D positive rhythm profile geological model by using the ASP numerical modeling software developed by RIPED (Yuan, et al. 1995). The recovery coefficient, remaining oil saturation, sweep efficiency and displacement efficiency were calculated and correlated layer by layer. The results show that the sweep efficiency and displacement efficiency work different effects on different layers in the severely heterogeneous reservoir. The study shows that the displacement efficiency and sweep efficiency play different roles in different layers for severely heterogeneous reservoirs. The displacement efficiency contributes mainly to the high permeability zones, the sweep efficiency to the low permeability zones, both of which contribute to the middle permeable zones. To improve the sweep efficiency in the low permeability zones is of significance for enhancing the whole recovery of the reservoir. It is an important path for improving the effectiveness of chemical flooding in the severely heterogeneous reservoirs to inject ternary combination slug after profile control.展开更多
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 f...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.展开更多
Water alternating gas(WAG)injection is a widely used strategy for enhancing oil recovery(EOR)during gas flooding,and the mechanisms,operating parameters,and influencing factors of which have been extensively studied.H...Water alternating gas(WAG)injection is a widely used strategy for enhancing oil recovery(EOR)during gas flooding,and the mechanisms,operating parameters,and influencing factors of which have been extensively studied.However,with respect to its capacity in expanding macroscopic sweep volume under varying heterogeneities,the related results appear inadequate.In this research,three cores with different heterogeneities were used and flooded by the joint water and CO_(2) WAG,then the effects of heterogeneity on oil recovery were determined.More importantly,the cores after CO_(2) WAG injection were investigated using the nuclear magnetic resonance(NMR)technique for remaining oil distribution research,which could help us to understand the capacity of CO_(2) WAG in enlarging sweep volume at different heterogeneities.The results show that the presence of heterogeneity may largely weaken the effectiveness of water flooding,the more severe the heterogeneity,the worse the water flooding.The WAG injection of CO_(2) performs well in EOR after water flooding for all the cores with different heterogeneities;however,it could barely form a complete or full sweep throughout the low-permeability region,and un-swept bypassed regions remain.The homogeneous core is better developed by the injection of the joint water and CO_(2) WAG than the heterogeneous and fractured cases.展开更多
Enhanced oil recovery （EOR） via carbon dioxide （CO2） flooding has received a considerable amount of attention as an economically feasible method for carbon sequestration, with many recent studies focus- ing on dev...Enhanced oil recovery （EOR） via carbon dioxide （CO2） flooding has received a considerable amount of attention as an economically feasible method for carbon sequestration, with many recent studies focus- ing on developing enhanced CO2 foaming additives, However, the potential long-term environmental effects of these additives in the event of leakage are poorly understood and, given the amount of additives injected in a typical CO2 EOR operation, could he far-reaching, This paper presents a summary of recent developments in surfactant and surfactant/nanoparticle-hased CO2 foaming systems, with an emphasis on the possible environmental impacts of CO2 foam leakage, Most of the surfactants studied are unlikely to degrade under reservoir conditions, and their release can cause major negative impacts on wildlife, With recent advances in the use of additives （e,g,, nonionic surfactants, nanoparticles, and other chemicals） the use of harsh anionic surfactants may no longer he warranted, This paper discusses recent advances in producing foaming systems, and highlights possible strategies to develop environmentally friendly CO2 EOR methods,展开更多
Almost the same quantity to net output work of energy has been carried out and wasted by exhaust gas in typical automotive engine. Recovering the energy from exhaust gas and converting to mechanical energy will dramat...Almost the same quantity to net output work of energy has been carried out and wasted by exhaust gas in typical automotive engine. Recovering the energy from exhaust gas and converting to mechanical energy will dramatically increase the heat efficiency and decrease the fuel consumption. With the increasing demand of fuel conservation, exhaust gas energy recovery technologies have been a hot topic. At present, many researches have been focused on heating or cooling the cab, mechanical energy using and thermo-electronic converting. Unfortunately, the complicated transmission of mechanical energy using and the depressed efficiency of thermo-electronic converting restrict their widely applying. In this paper, a kind of exhaust gas energy recovery system of pneumatic driving automotive engine, in which highly compressed air acts as energy storing and converting carrier, has been established. Pneumatic driving motor can produce moderate speed and high torque output, which is compatible for engine using. The feasibility has been certificated by GT-Power simulation and laboratory testes. The technologies about increasing recovery efficiency have been discussed in detail. The results demonstrated that the in parallel exhaust gas energy recovery system, which is similar to the compound turbo-charger structure can recovery 8 to 10 percent of rated power output. At last, a comprehensive system, which includes Rankine cycle based power wheel cycle unit etc., has been introduced.展开更多
基金This project is supported by the China National Key Basis Research Project (No: G1999022512)
文摘The processes of flooding—water flooding, polymer flooding and ternary combination flooding—were simulated respectively on a 2-D positive rhythm profile geological model by using the ASP numerical modeling software developed by RIPED (Yuan, et al. 1995). The recovery coefficient, remaining oil saturation, sweep efficiency and displacement efficiency were calculated and correlated layer by layer. The results show that the sweep efficiency and displacement efficiency work different effects on different layers in the severely heterogeneous reservoir. The study shows that the displacement efficiency and sweep efficiency play different roles in different layers for severely heterogeneous reservoirs. The displacement efficiency contributes mainly to the high permeability zones, the sweep efficiency to the low permeability zones, both of which contribute to the middle permeable zones. To improve the sweep efficiency in the low permeability zones is of significance for enhancing the whole recovery of the reservoir. It is an important path for improving the effectiveness of chemical flooding in the severely heterogeneous reservoirs to inject ternary combination slug after profile control.
文摘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.
基金Project(KFJJ-TZ-2019-3)supported by the Open Project of Shaanxi Key Laboratory of Advanced Stimulation Technology for Oil&Gas Reservoirs,ChinaProjects(51504275,51974344)supported by the National Natural Science Foundation of China。
文摘Water alternating gas(WAG)injection is a widely used strategy for enhancing oil recovery(EOR)during gas flooding,and the mechanisms,operating parameters,and influencing factors of which have been extensively studied.However,with respect to its capacity in expanding macroscopic sweep volume under varying heterogeneities,the related results appear inadequate.In this research,three cores with different heterogeneities were used and flooded by the joint water and CO_(2) WAG,then the effects of heterogeneity on oil recovery were determined.More importantly,the cores after CO_(2) WAG injection were investigated using the nuclear magnetic resonance(NMR)technique for remaining oil distribution research,which could help us to understand the capacity of CO_(2) WAG in enlarging sweep volume at different heterogeneities.The results show that the presence of heterogeneity may largely weaken the effectiveness of water flooding,the more severe the heterogeneity,the worse the water flooding.The WAG injection of CO_(2) performs well in EOR after water flooding for all the cores with different heterogeneities;however,it could barely form a complete or full sweep throughout the low-permeability region,and un-swept bypassed regions remain.The homogeneous core is better developed by the injection of the joint water and CO_(2) WAG than the heterogeneous and fractured cases.
基金support from the American Chemical Society Petroleum Research Fund (ACS-PRF) (55801-DNI6)
文摘Enhanced oil recovery （EOR） via carbon dioxide （CO2） flooding has received a considerable amount of attention as an economically feasible method for carbon sequestration, with many recent studies focus- ing on developing enhanced CO2 foaming additives, However, the potential long-term environmental effects of these additives in the event of leakage are poorly understood and, given the amount of additives injected in a typical CO2 EOR operation, could he far-reaching, This paper presents a summary of recent developments in surfactant and surfactant/nanoparticle-hased CO2 foaming systems, with an emphasis on the possible environmental impacts of CO2 foam leakage, Most of the surfactants studied are unlikely to degrade under reservoir conditions, and their release can cause major negative impacts on wildlife, With recent advances in the use of additives （e,g,, nonionic surfactants, nanoparticles, and other chemicals） the use of harsh anionic surfactants may no longer he warranted, This paper discusses recent advances in producing foaming systems, and highlights possible strategies to develop environmentally friendly CO2 EOR methods,
基金National Natural Science Foundation of China ( No. 50976046)
文摘Almost the same quantity to net output work of energy has been carried out and wasted by exhaust gas in typical automotive engine. Recovering the energy from exhaust gas and converting to mechanical energy will dramatically increase the heat efficiency and decrease the fuel consumption. With the increasing demand of fuel conservation, exhaust gas energy recovery technologies have been a hot topic. At present, many researches have been focused on heating or cooling the cab, mechanical energy using and thermo-electronic converting. Unfortunately, the complicated transmission of mechanical energy using and the depressed efficiency of thermo-electronic converting restrict their widely applying. In this paper, a kind of exhaust gas energy recovery system of pneumatic driving automotive engine, in which highly compressed air acts as energy storing and converting carrier, has been established. Pneumatic driving motor can produce moderate speed and high torque output, which is compatible for engine using. The feasibility has been certificated by GT-Power simulation and laboratory testes. The technologies about increasing recovery efficiency have been discussed in detail. The results demonstrated that the in parallel exhaust gas energy recovery system, which is similar to the compound turbo-charger structure can recovery 8 to 10 percent of rated power output. At last, a comprehensive system, which includes Rankine cycle based power wheel cycle unit etc., has been introduced.
