【摘要】 将CO₂注入油层,不仅封存了CO₂,还可以大幅度提高油气田采收率,达到CO₂减排和油藏高效开发的双赢目的,受到了相关研究者的广泛重视。如何有效地降低CO₂与原油之间的混相压力,是目前CO₂驱提高采收率研究的主要热点和难点之一。文中比较了降低CO₂驱混相压力的几种方法,探索新的亲CO₂表面活性剂以降低CO₂驱最小混相压力。目前,降低CO₂驱混相压力的主要方法有添加共溶剂法,但成本比较高;超临界CO₂微乳液法可以降低CO₂驱混相压力,但是目前表面活性剂的研究主要集中在降低油/水界面张力的离子型表面活性剂,关于降低油/CO₂界面张力的非离子表面活性剂还鲜有报道;亲CO₂表面活性剂是降低CO₂驱混相压力的一种新探索,但目前已用的表面活性剂与CO₂的亲和性差,使得CO₂对极性较强的大分子物质的溶解能力受到限制。因此,开发新的亲CO₂表面活性剂以达到降低CO₂驱混相压力的效果显得尤为关键。更多还原

【Abstract】 A win-win purpose of Carbon Dioxide（CO₂）emissions and efficient reservoir development can be achieved by injecting CO₂ into reservoir.How to effectively reduce miscibility pressure between CO₂ and crude oil,is one of the major hot and difficult problems for enhancing oil recovery by CO₂ flooding.The methods of miscibility pressure reduction using CO₂ flooding are compared,and new efficient CO₂-philic surfactants are explored.Currently,mixing cosolvent with CO₂ is limited by the price.Supercritical CO₂ micromulsion can also reduce the miscibility pressure,while the main study is focused on reducing oil/water interfacial tension of ionic surfactants.Nonionic surfactants that can reduce oil/CO₂ interfacial tension are rarely reported.Dissolving capacity of polar compounds in CO₂ is small for the poor compatibility between CO₂ and nonionic surfactant.So,the key to reduce miscibility pressure is CO₂-philic surfactant.更多还原