Khademolhosseini Rasoul, Jafari Arezou, Mousavi Seyyed Mohammad, Manteghian Mehrdad
Faculty of Chemical Engineering, Tarbiat Modares University Tehran Iran
Biotechnology Group, Chemical Engineering Department, Tarbiat Modares University Tehran Iran
RSC Adv. 2019 Jun 28;9(35):20281-20294. doi: 10.1039/c9ra02039j. eCollection 2019 Jun 25.
The purpose of this study was to investigate the effect of process parameters including silica nanoparticle (NP) concentration, biosurfactant (BS) concentration, and salinity as well as their synergistic effects on oil recovery in simultaneous flooding. Additionally, the effect of NP morphology (in the BS-NP solution) on oil recovery was investigated in this research. Micromodel flooding tests were designed with a central composite design (CCD) and carried out using BS and spherical silica NPs. The results showed that there is a positive synergistic effect between BS and silica NPs to shift the wettability to the water-wet condition and decrease interfacial tension (IFT), resulting in improved oil recovery. Indeed, the maximum oil recovery was obtained at an optimum salt concentration. Several micromodel tests were then carried out with BS and different-shaped NPs at the optimum point predicted by a mathematical model to study the effect of NP morphology on oil recovery. The results showed that minimum IFT of 1.85 mN m and the most reduction in the glass contact angle of 92.8% could be achieved by the BS-spherical NP solution as compared to those of the BS-non spherical NP solutions, which led to the highest oil recovery of 53.4%. The better performance of spherical NPs was attributed to the higher uniformity, which resulted in better distribution and more effective interactions with crude oil components. The results of core flooding tests showed that the BS-spherical NP solution yielded 26.1% final oil recovery after brine flooding. In addition, the BS-NP solution was more effective in wettability alteration of an oil-wet carbonate rock compared with the BS solution. It was deduced that the main mechanisms involved in oil recovery improvement were wettability alteration to the water-wet state, IFT reduction, and mobility ratio improvement.
本研究的目的是调查包括二氧化硅纳米颗粒（NP）浓度、生物表面活性剂（BS）浓度、盐度等工艺参数及其协同效应在同时驱油过程中对原油采收率的影响。此外，本研究还考察了NP形态（在BS-NP溶液中）对原油采收率的影响。采用中心复合设计（CCD）设计了微观模型驱油试验，并使用BS和球形二氧化硅NP进行试验。结果表明，BS和二氧化硅NP之间存在正协同效应，可使润湿性转变为水湿条件并降低界面张力（IFT），从而提高原油采收率。实际上，在最佳盐浓度下可获得最大原油采收率。然后在数学模型预测的最佳点进行了几次使用BS和不同形状NP的微观模型试验，以研究NP形态对原油采收率的影响。结果表明，与BS-非球形NP溶液相比，BS-球形NP溶液可实现最低IFT为1.85 mN/m以及玻璃接触角最大降低92.8%，从而实现最高原油采收率53.4%。球形NP的更好性能归因于更高的均匀性，这导致更好的分布以及与原油组分更有效的相互作用。岩心驱油试验结果表明，BS-球形NP溶液在水驱后最终原油采收率为26.1%。此外，与BS溶液相比，BS-NP溶液在改变油湿碳酸盐岩的润湿性方面更有效。据推断，提高原油采收率的主要机制是润湿性转变为水湿状态、IFT-NP溶液在改变油湿碳酸盐岩的润湿性方面更有效。据推断，提高原油采收率的主要机制是润湿性转变为水湿状态、IFT降低和流度比提高。
