Petroleum Engineering – Reservoir
Seyed Reza Shadizadeh; Seyed Ramin Seyedi Abandankashi; Siyamak Moradi
Abstract
In recent years, the use of natural surfactants as surface active agents in chemical methods of oil recovery over chemical surfactants has been under consideration due to the absence of environmental problems. In this study, a new plant, Albizia julibressin (Albizia), was introduced as a natural surfactant. ...
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In recent years, the use of natural surfactants as surface active agents in chemical methods of oil recovery over chemical surfactants has been under consideration due to the absence of environmental problems. In this study, a new plant, Albizia julibressin (Albizia), was introduced as a natural surfactant. Our novelty resides in a unified approach that deals with the introduction of Albizia julibressin (Albizia) as a new natural surfactant, interpretation of the chemical EOR objectives, interface reactions, and the induced optimization to improve oil recovery. For this purpose, the plant was extracted using Soxhlet extraction method, aqueous base solutions and interfacial tension between natural surfactant aqueous solutions and kerosene as an oil phase were measured by pendant drop method. The critical micelle concentration structures formed by this material has been determined by interfacial tension tests and confirmed by electrical conductivity tests. The results show that Albizia extract at 3.5 wt% begins to form micelles structures, which is the critical concentration of Albizia plant micelles. At this concentration, the interfacial tension between the deionized water and the oil phase is reduced from 34 mN /m to 10 mN/m, which indicates a significant decrease in interfacial tension by this plant. Carbonate rock was employed to core flooding experiments in order to investigate the effect of Albizia extract (AE) on oil recovery. Also based on results, by using AE, wettability of oil-wet carbonate rocks, was altered from about 165.02◦ to 86.59◦. Finally, AE enhanced ultimate oil recovery about 11.6% of original oil in place in tertiary recovery for a carbonate rock.
Petroleum Engineering
Yaser Ahmadi; Babak Aminshahidy
Abstract
This paper addressed the application of new hydrophobic synthesized calcium oxide (CaO) and silicon dioxide (SiO2) nanofluids to low permeability carbonate porous media. Crude oil and plugs were selected from one of oil reservoirs in the west of Iran. The main goal of this paper is comparing the results ...
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This paper addressed the application of new hydrophobic synthesized calcium oxide (CaO) and silicon dioxide (SiO2) nanofluids to low permeability carbonate porous media. Crude oil and plugs were selected from one of oil reservoirs in the west of Iran. The main goal of this paper is comparing the results of improving water-oil relative permeability parameters in low permeability plugs of carbonate cores in the presence of new synthesized CaO and SiO2 nanofluids. All the experiments were performed at a temperature of 40 °C and at a nanoparticle concentration of 45 ppm. The experimental approaches were designed into two main steps: 1) the effects of both nanoparticles on the changes in interfacial tension (between oil and brine) and oil viscosity 2) the effects of both nanoparticles on wettability (qualitatively) and relative permeability parameters. SiO2 and CaO decreased interfacial tension from 46.414 mN/m to 41.772 mN/m and 32.860 mN/m respectively. Moreover, SiO2 and CaO decreased oil viscosity from 9.90 cP to 8.61 cP and 8.01 cP respectively. Based on the obtained results in the core flood experiments, although CaO and SiO2 nanofluids decreased effective water permeability, effective oil permeability and ultimate oil recovery increased. Moreover, it was seen that the CaO nanofluid improved oil flow in carbonate cores more than the commercial SiO2 flooding. Finally, it was seen that both nanoparticles change the wettability from oil-wet to water-wet (qualitatively).
Petroleum Engineering
Mohammad Hossein Shabani; Arezou Jafari; Seyed Mohammad Mousavi
Abstract
Microbial enhanced oil recovery (MEOR) is an economical method used to improve the oil recovery from reservoirs. In the MEOR techniques, by applying different microorganisms, a variety of products such as bioacid, biogas, biosurfactant, and biopolymer are generated, among which biosurfactant, one of ...
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Microbial enhanced oil recovery (MEOR) is an economical method used to improve the oil recovery from reservoirs. In the MEOR techniques, by applying different microorganisms, a variety of products such as bioacid, biogas, biosurfactant, and biopolymer are generated, among which biosurfactant, one of the important metabolites, is produced by bacteria. It is worthy to note that bacteria are suitable candidates to enhance oil recovery due to their small size, rapid growth, capability of tolerating reservoir conditions, and production of different metabolites. Therefore, in this research, two bacteria, namely Enterobacter cloacae subsp with PTCC: 1798 isolated from oil-contaminated soil in south of Iran and Acinetobacter Calcoaceticus with PTCC: 1318, are used to produce biosurfactants. In order to evaluate the performance of generated biosurfactants, ex-situ flooding tests were performed in a glass micromodel to visualize the oil displacement and fluid front flow. In addition, water flooding is performed as a common EOR method for the better investigation of the produced biosurfactants. The results represented that injecting Enterobacter with a salinity concentration of 6% and Acinetobacter with a salinity concentration of 3% respectively increases the oil recovery factor by 27 and 35% compared to water flooding. In other words, the highest reduction in interfacial tension is achieved by the biosurfactant produced from Enterobacter and Acinetobacter at 6% and 3% salinity respectively, and the sequent changes in the interfacial tension are from 45 to 7 and 45 to 4 mN/m.
