摘要
砂砾岩储集层岩石颗粒混杂、非均质性强、孔隙结构复杂，克拉玛依油田砂砾岩储集层注水开发面临易水窜和水淹、综合含水率高、采收率低等问题，须开展砂砾岩储集层聚合物驱室内评价实验，为合理制定开发方案提供参考。以克拉玛依油田七东1区克拉玛依组下亚组砂砾岩储集层为研究对象，结合压汞、铸体薄片等手段，表征砂砾岩储集层不同类型孔隙结构特征，选择有代表性的岩心开展水驱与聚合物驱实验，通过核磁共振检测驱替过程中聚合物驱油效率、原油动用规律以及聚合物驱后剩余油分布特征。研究结果表明，不同类型孔隙结构差异较大，聚合物驱油潜力不同，其中Ⅱ类孔隙结构聚合物驱提高驱油效率最高；半径大于10.0 μm的孔喉中的原油水驱动用程度最高，聚合物驱提高原油驱油效率有效孔喉半径为1.0~10.0 μm，孔喉半径小于1.0 μm的孔隙对聚合物驱油贡献率低，聚合物驱平均提高驱油效率13.09% .
Sandy conglomerate reservoir is characterized by mixed rock grains, strong heterogeneity and complex pore structures. Waterflooding in the sandy conglomerate reservoirs in Karamay oilfield encounters some problems such as water channeling and watered out, high overall watercut and low recovery factor etc., so indoor experiment and evaluation should be carried out for the sandy conglomerate reservoirs to provide guidance for reasonably making development scheme. This paper takes the sandy conglomerate reservoir in T2k1 of Karamay formation in District Qidong-1, Karamay oilfield as the research object, describes the characteristics of different pore structures in the reservoir on the basis of mercury injection and casting thin section analysis. Some typical cores are selected for waterflooding and polymer flooding experiments. Oil displacement efficiency and oil producing rule during displacement process and residual oil distribution after polymer flooding are determined by NMR. The results show that big differences among different types of pore structures result in different polymer flooding potentials, the highest oil displacement efficiency is obtained in Type Ⅱ pore structures; the highest oil producing degree by waterflooding is observed in the pore throats with the radius larger than 10.0 μm. The effective pore throat radius ranges from 1.0 to 10.0 μm for polymer flooding. The pores with the pore throat radius less than 1.0 μm make the lowest contribution for polymer flooding and the oil displacement efficiency of polymer flooding can be improved by 13.09% on average .
出处
《新疆石油地质》
CAS
CSCD
北大核心
2016年第5期549-555,共7页
Xinjiang Petroleum Geology
关键词
拉玛依油田
七东1区
砂砾岩储集层
孔隙结构
聚合物驱
驱油效率
原油动用规律
Karamay oilfield
District Qidong-1
sandy conglomerate reservoir
pore structure
polymer flooding
oil displacement efficiency
oil producing rule
