长庆油田特低渗油藏空气泡沫驱室内评价

Indoor Evaluation of Air Foam Flooding in Extra-Low Permeability Reservoirs of Changqing Oilfield

长庆低渗透、特低渗透油藏目前在提高采收率技术方面没有成熟的应用，为了高效开发该类油藏，进行室内空气泡沫驱提高采收率实验，实验通过一维和二维岩心实验，对实验过程中驱油效率、渗透率与驱油效率的关系以及含水率的变化进行了研究。结果表明：低渗透、特低渗透油藏采用空气泡沫驱能有效提高驱油效率，平均提高23．56％：能有效降低含水率，达到控水稳油的目的；空气泡沫驱能有效提高低渗透岩心的驱油效率，封堵高渗段油藏，对平面矛盾突出的油藏能提高驱替过程的波及体积。

The CQ oil reservoirs with low- and extra-low permeability do not have matured application in the technical aspect of EOR （enhancing oil recovery ratio）. To effectively develop the oil reservoir of the same type, the experiment of indoor air foam flooding for increasing the recovery ratio is carried out. Through one dimensional and two dimensional rock core experiments, and during the process of the experiment, the oil flooding efficiency, the relationship between permeability and oil flooding efficiency and the change of water content rate are researched. The result shows： to the oil reservoir of low permeability and super-low permeability, the air foam flooding can be used for effectively increasing the oil flooding efficiency, and the average increase is 23.56%. The water content rate can be effectively decreased to control water and stabilize oil. The air foam flooding can effectively increase the oil flooding efficiency of the low-permeability rock core, block the oil reservoir of high-permeability section, and increase the swept volume of the oil reservoir with prominent planar contradiction during the flooding process.