纳米流体提高采收率机理研究现状

Research Status on Mechanism of Enhanced Oil Recovery by Nanofluids

与传统的表面活性剂和聚合物溶液相比,纳米流体驱油是一项新的提高采收率技术,但目前机理研究成果较为分散,缺少系统性。因此,结合国内外纳米流体研究情况,总结纳米流体主要提高采收率机理,指出了纳米流体目前所面临的研究难点,展望了纳米材料在今后的攻关方向。研究表明:纳米流体提高采收率机理包括降低油水界面张力,在油水固三相区形成楔形膜,产生结构分离压力,改善流度比扩大波及体积,改变岩石润湿性,增强泡沫稳定性,降低注入压力和选择性调堵孔道;今后可从提高纳米流体稳定性、降低纳米流体成本、提高采收率机理协同性研究以及开发高效纳米驱油体系等方面进行深入探索。该研究为大规模推广纳米流体在提高采收率方面的应用提供了理论基础和实验依据。

As a new technology to enhance oil recovery,nanofluid flooding has advantages over traditional surfactants and polymer solutions flooding.However,the current research on the mechanism of this technology is not systematic.Based on the research progress of nanofluids at home and abroad,this study summarizes the main EOR mechanism of nanofluid flooding.Meanwhile,the current difficulties faced by this technology and the future research direction are pointed out.The results show that the EOR mechanism of nanofluids flooding includes:reducing oil-water interfacial tension;forming a wedge-shaped film in three-phase(oil-water-solid)zone,which results in the pressure of structural separation;improving the mobility ratio to expand the swept area;altering the wettability of rock;enhancing foam stability;reducing injection pressure and selecting the porous channels of water plugging.Future research can focus on improving the stability of nanofluids,reducing costs,conducting synergistic studies on the mechanisms of enhanced oil recovery,and developing efficient nano-flooding systems.This study lays a theoretical and experimental foundation for the large-scale application of nanofluids in enhanced oil recovery process.