低渗油藏采收率确定新方法

A new approach to determine oil recovery in low permeability reservoirs

黄小亮 唐海 吕栋梁 李仲 吕浙江 余贝贝

Huang Xiaoliang Tang Hai Lv Dongliang Li Zhong Lv Zhejiang Yu Beibei

西南石油大学, 四川成都 610500; 西南油气田川东北气矿, 四川达州 635000

Southwest Petroleum University, Chengdu 610500; Northeast Sichuan Gas Field of Southwest Oil and Gas Field, Dazhou 635000

通过对油藏相渗曲线的归一化处理, 利用达西定律理论, 建立采油指数与含水率的关系;再通过油藏确定的单井经济极限采油量和油藏极限生产压差求出极限采油指数, 从而得到极限含水率;最后以最终水驱体积波及系数与储层退汞效率计算出采收率。并以低渗透油藏为实例验证了该方法的正确与适用性, 说明该方法对油田开发中确定低渗油藏采收率具有科学的指导意义。

A new approach to determine oil recovery in low permeability reservoirs was introduced in this paper. Firstly, through the normalization of relative permeability curve and utilizing Darcy law, relationship between productivity index and water cut was established. Secondly, ultimate water cut can be obtained through economic limit oil production of single well and ultimate producing pressure drop of the reservoir. Finally, recovery efficiency has been calculated using the volume of water flooding and reservoir mercury ejection efficiency. The successful application of this method to low permeability reservoirs showed it had scientific significance to determine oil recovery rate in low permeability reservoirs.