低渗油藏纳米膜增注技术研究与应用

The research and application of injection technology of nanometer film in low-permeability reservoir

针对低渗油藏物性差,在注水开发过程中存在注水井注入压力高、注水量不能满足配注要求的突出问题,提出酸化处理后通过注入一种带有阳离子基团的纳米膜剂溶液来改善储层的润湿性,提高储层吸水能力,进一步提高水驱采收率的技术。纳米膜以水溶液为介质,依靠静电作用成为膜动力,吸附到呈负电性的岩石表面,改变储层表面的润湿性,降低注入水在孔隙中的流动阻力,避免粘土颗粒的膨胀与运移,从而提高水相渗透率,降低注水压力,达到降压增注的目的。室内实验研究及现场应用表明,该纳米膜可以改善低渗油藏注水井的注水开发效果。

In low-permeability reservoir, the physical properties is poor. And the injection pressure is high and the injected water volume is low during the oilfield development. It is proposed that a kind of the monolayer solution with cationic group could be used to solve this problem. It can improve the reservoir wettability.Nanometer film is in aqueous solution as the delivery medium, electrostatic interactionis the driving force, improve the reservoir wettability, reduce the resistance of the injected water in the pore, prevents clay swelling and migration. Thereby it can enhance the penetration of water phase, reduce water pressure, ultimately reduce pressure and augment injection. Laboratory exoeriments and oilfield aplicate that thistechnology can be used to increase the ability to absorb water of injection in lowpermeability reservoir, to improve water injection effect.