The Secondary Development Countermeasures Of High Water Cut Period In Low Permeability Oilfield

Waterflooding is the major way to development the low permeability oilfield,and to thelate period of oilfield is in high water cut period or extra high water cut stage.According tostatistics,when production ratio in recoverable reserves is about2/3in our country,but theaverage water cut has more than80%.Therefore,the development of high water cut stage willbe the main stage in our study.the oil well water cut increase quickly and the production ratedecrease fast in the high water cut stage,so it’s difficult to adjust the development plan. Inorder to resolve this contradiction,fundamentally improve development effect,achieve thesustained and effective development of the oil deposit.The secondary development oftechnical countermeasures research in low permeability oil deposit is particularly important.In order to solve this problem, this article selected a low permeability oil deposit of tuhaoilfield as an example. Firstly introduces the basic geologic and development characteristicsof the oil field, and then carry out the reservoir engineering and numerical simulation studyfor quantitative analysis of remaining oil,concluded that remaining oil distribution law andadjustable thickness in different development horizon.Use different methods to predict therecovery efficiency and lay the foundation for the following study.The study of secondary development technology countermeasures,included increase thedegree of residual oil use by adjust well pattern and improve oil displacement efficiency.Wellpattern adjustment,included vertical wells network encryption,horizontal and vertical Wellswell network encryption.To improve oil displacement efficiency,first determine the feasibilityof increase the water viscosity,and then provide different scheme of the thickened waterinjection.Finally comparied all the plan of production index,select the optimal one as the finalsolution.