石南21井区分子膜增注技术研究与实践

The Research and Practice of Augmented Injection Technology of Molecular Film in Liuliang Oilfield

针对石南21井区低渗透、特低渗透油藏在注水开发过程中存在注水井注入压力高、注水量不能满足地质配注的突出问题,提出通过注入一种带阳离子基团的分子膜剂溶液来改善油藏吸水能力,进一步提高水驱采收率的技术。分子膜以水溶液为传递介质,膜剂分子依靠静电作用作为成膜动力,膜剂有效分子沉积在呈负电性的岩石表面,改变储层表面的性质,剥落水膜,阻止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。室内试验研究及现场应用实践表明,分子膜可以提高石南21井区注水井的吸水能力,改善注水开发效果。

In Luliang Oilfield,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.Monolayers is in aqueous solution as the delivery medium,electrostatic interactionis the driving force,it deposites on the negative power of the rock surface,changes the nature of the surface reservoir,peel water film,prevents clay swelling and migration,thereby it can enhance the penetration of water phase,reduce water pressure,ultimately reduce pressure and augment injection.Laboratory experiments and oilfield application indicate that this technology can be used to increase the ability to absorb water of injection wells in Shinan 21 Area of Luliang Oilfield,improve water injection effect.