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.
Masoumeh Tajmiri; Seyed Mousa Mousavi; Mohammad Reza Ehsani; Emad Roayaei; Ali Emadi
Abstract
Efforts to enhance oil recovery through wettability alteration by nanoparticles have been attracted in recent years. However, many basic questions have been ambiguous up until now. Nanoparticles penetrate into pore volume of porous media, stick on the core surface, and by creating homogeneous water-wet ...
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Efforts to enhance oil recovery through wettability alteration by nanoparticles have been attracted in recent years. However, many basic questions have been ambiguous up until now. Nanoparticles penetrate into pore volume of porous media, stick on the core surface, and by creating homogeneous water-wet area, cause to alter wettability. This work introduces the new concept of adding ZnO nanoparticles by an experimental work on wettability alteration and oil recovery through spontaneous imbibition mechanism. Laboratory tests were conducted in two experimental steps on four cylindrical core samples (three sandstones and one carbonate) taken from a real Iranian heavy oil reservoir in Amott cell. In the first step, the core samples were saturated by crude oil. Next, the core samples were flooded with nanoparticles and saturated by crude oil for about two weeks. Then, the core samples were immersed in distilled water and the amount of recovery was monitored during 30 days for both steps. The experimental results showed that oil recovery for three sandstone cores changed from 20.74, 4.3, and 3.5% of original oil in place (OOIP) in the absence of nanoparticles to 36.2, 17.57, and 20.68% of OOIP when nanoparticles were added respectively. Moreover, for the carbonate core, the recovery changed from zero to 8.89% of OOIP by adding nanoparticles. By the investigation of relative permeability curves, it was found that by adding ZnO nanoparticles, the crossover-point of curves shifted to the right for both sandstone and carbonate cores, which meant wettability was altered to water- wet. This study, for the first time, illustrated the remarkable role of ZnO nanoparticles in wettability alteration toward more water-wet for both sandstone and carbonate cores and enhancing oil recovery.
Mohammad Amin Safarzadeh; Seyyed Alireza Tabatabaei Nezhad; Eghbal Sahraei; Mehdi Mohammad Salehi
Abstract
The main factor affecting the economics of foam-assisted water alternative gas (FAWAG) process is the loss of foaming agent by adsorption onto reservoir rocks. In this study, the effects of phases, surfactant concentration, salinity, adsorbents, and sacrificial agent on adsorption density were investigated ...
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The main factor affecting the economics of foam-assisted water alternative gas (FAWAG) process is the loss of foaming agent by adsorption onto reservoir rocks. In this study, the effects of phases, surfactant concentration, salinity, adsorbents, and sacrificial agent on adsorption density were investigated by special adsorption experiments. Moreover, a series of FAWAG tests were performed to examine the effect of injection rates on final adsorption density and adsorption variation during the test. A clean and fast spectrophotometric method was used for the determination of sodium dodecyl sulfate (SDS) concentration based on the formation of an ion-pair, SDS-Safranin O. Higher SDS adsorption was observed at the first cycle of FAWAG flooding. FAWAG injection rate had no noticeable effect on the adsorption density. However, using high injection rate decreased the possibility that gas faces surfactant, and thereby reducing the ultimate oil recovery. The presence of CLS increases the ultimate oil recovery slightly, while it decreases the adsorption density of SDS by 22%.
