改变低渗透油藏润湿性提高采收率技术研究进展

Research progress of EOR with alteration of rock wettability in low-permeability reservoir

油藏岩石润湿性是储层物性的一个基本特征参数,是影响油田特别是混合润湿或油湿性低渗透油田开发的重要因素。文中针对目前通过改变油藏岩石润湿性以提高原油采收率方面的相关技术及研究进行了详细调研,系统总结了改变油湿性油藏岩石润湿性以提高原油采收率的方法。经过归纳总结,认为目前这些方法主要分为物理法、化学法和微生物法3大类。润湿性转变的机理是通过剥离岩石表面吸附的极性组分,还原岩石表面的亲水性;或在岩石表面形成双层吸附,使岩石表面润湿性反转为水湿,增加毛细管力的渗吸驱油作用。在充分认识岩石润湿性反转机理的基础上,有针对性地调节油藏岩石的润湿性,从而可以达到提高采收率的目的。

Rock wettability of reservoir is a basic characteristic parameter of reservoir property and it can affect the oilfield development, especially in low-permeability reservoir with mixed wettability and oil wettability. This paper analyzes the relative techniques of ahering the rock wettabilily of oil reservoir to enhance the recovery ratio of crude oil and sums up the methods of ahering rock wettability of oil reservoir with oil wettability to enhance the recovery ratio. The methods can be divided into three categories： physical, chemical and microbial methods, h is believed that the mechanism of wettability alteration is to restore the wetlability of rock surface or to creale the double htyer adsorption on rock surface in order to make the wettability of rock surface reverse into water wet and improve the imbibition displacement action of capillary pressure through the stripping of polar comonent adsorbed by rock surface. Based on the sufficient understanding of wettability aheration meehanisms, the targeted adjustment of rock wettability of reservoir can realize the objective to enhance oil recovery.