低渗透油藏聚合物驱启动压力梯度研究  

Start-up pressure gradient of polymer flooding in low permeability reservoirs

作　　者：王友启[1] 于洪敏[1] 刘平[1] 许关利[1] 张莉[1] 聂俊[1] 

机构地区：[1]中国石化石油勘探开发研究院,北京100083

出　　处：《中国石油大学学报（自然科学版）》2015年第4期126-130,共5页Journal of China University of Petroleum(Edition of Natural Science)

基　　金：中国石油化工股份有限公司科技攻关项目(P13124)

摘　　要：为了描述低渗透油藏聚合物驱的渗流规律及启动压力梯度特征,借鉴水驱启动压力梯度的试验测定方法,将压差-流量法和毛细管平衡法相结合,在不同储层渗透率和体系黏度下开展低渗透储层聚合物驱渗流试验;在此基础上,基于非线性渗流理论量化表征聚合物驱启动压力梯度,建立聚合物驱非线性渗流系数与体系黏度、储层渗透率和流度的量化关系。结果表明,随着储层渗透率的降低或体系黏度的增大,相同渗流速度下聚合物驱的渗流阻力增加、压力梯度增大;聚合物渗流曲线用非线性方法表征吻合较好,且随着储层渗透率降低、体系黏度增大或流度降低,聚合物驱非线性渗流系数均增大;流态图版包含对不流动区、非线性渗流区和拟线性渗流区的定量描述。Polymer flooding experiments are conducted using cores with different permeability and polymer solutions with differ- ent viscosity, in order to study the flow behavior in porous media and the characteristics of the start-up pressure gradient for polymer injection in oil reservoirs with low permeability. A combined method of differential pressure via flow rate and capillary equilibrium was used in the core flooding experiments. Based on the theory of nonlinear flow in porous media, the start-up pres- sure gradient for polymer flooding was characterized quantitatively, and was correlated with the non-linear flow coefficient, the viscosity of polymer solution, the permeability of the core and fluid＇s mobility. A flow chart of polymer flow in low permeability reservoirs has been figured out. The results show that the flow resistance and the start-up pressure gradient increase with the decrease of core permeability and the increase of polymer viscosity. The flow behavior of polymer solutions in porous media can be well described using the nonlinear characterization method, and the nonlinear flow coefficient increases with the decrease of core＇s permeability and the fluid mobility, and it increases with the increase of polymer viscosity. The flow chart can give a quantitative description of different flow regions, such as no-flow zones, non-linear and quasi-linear flow zones.

关 键 词：低渗透 聚合物驱 启动压力梯度 非线性渗流 试验 表征 图版 

分 类 号：TE312[石油与天然气工程—油气田开发工程]