缝洞型储层全直径岩心注气吞吐替油实验研究

摘要

The major reservoir space of fracture-vug carbonate reservoir includes large caves, dissolved pores and fractures. In wa⁃ter injection development stage, water breakthrough is fast in the oil production wells and the recovery efficiency is low. The full di⁃ameter outcrop core of Tahe are cut into half, and made sewing and hole in each half based on geological model of well-TK404. The samples are made by oil and gas in site. In different injection gas types and puff and huff times, different ways to reduce pressure and different ways of filling conditions, the recovery efficiency of full diameter core physical experiment was researched. The result showed that N2 and CO2 have great oil increase effects when puff and huff, and the slower depressurizing rate and the filled porous media can improve oil recovery in the experiment.%缝洞型碳酸盐岩油藏通常以大型溶洞、溶蚀孔洞及裂缝为主要储集空间，注水开发阶段油井见水快且采收率低，采用注气吞吐可以有效提高采收率。取得塔河油田全直径岩心样品进行对半剖分，根据TK404井地质模型刻蚀造洞，并采取现场油气样品进行活油复配。在不同注入气类型、不同吞吐次数、不同降压方式以及不同填充方式等条件下，完成了全直径岩心吞吐替油提高原油采出程度实验研究。结果显示，吞吐时使用N2、CO2均有良好增油效果，减缓吐气降压速度、模拟多孔介质填充可在实验中提高采收程度。