Flow Direction Optimization Method Under Reservoir Architecture Control Of High Water Cut Oilfield In Wen25 Dong Reservoir

Zhongyuan Oilfield has entered the stage of high water cut development at present,in which the water cut of complex fault block is 94%.Because of the unclear understanding of reservoir plane heterogeneity and water drive wave,and the immature flow direction technique,the potential development is becoming worse.In order to improve the development effect of water flooding,it is necessary to optimize the direction of fluid flow to further enhance oil recovery of water flooding.This paper takes the high water cut reservoir of Wen25 Dong reservoir as the research object,combination of numerical simulation and optimal theory,realization of dynamic reservoir optimization,quantitative reservoir production and injection proration,to realize the reasonable distribution of underground flow,improve the development level of water flooding.Wen25 Dong reservoir is a typical representative of medium permeability reservoir,it is located in the northern part of Wen Liu tectonic of the central uplift belt of tectonic stay in Dongpu depression,the decline in the disc of Wendong fault,it is the graben area of Wen Zhong development zone.The reservoir type belongs to reverse ridge bedded fault block reservoir,which belongs to delta deposit and it is typical positive rhythm sedimentary.Wen25 Dong block put into development in July 1979,after thirty years of high-speed development and many comprehensive adjustment and control,and achieved good development results.At present,due to many years of water injection development,the contradictions within the layer are further intensified.Because the block started adjustment and control of development degree of second class and third class layers in 1990,therefore,at present not only the main producing layer is good,the flooding is serious,two class or three class layers producing degree is higher,and has different flooding degrees,water flooding effect is getting worse year by year,injected water inefficient circulation is serious,the oil wells in the main blocks are high water cut.In order to optimize the development effect of water flooding,it is necessary to optimize the direction of fluid flow to further enhance oil recovery of waterflooding.In view of the problems of large change of reservoir,serious heterogeneity,scattered distribution of remaining oil and low water flooding efficiency of Wen25 Dong reservoir,through the establishment of Dongpu sag delta front reservoir architecture model,analyzes the internal architecture of the reservoir;using the large size flat model liquid flow optimization experiment,clear the law of water flooding pattern and optimization principle;the establishment of automatic optimization method of dynamic distribution coefficient adjusting the direction of liquid flow,to improve the efficiency of water flooding and the purpose of reducing the cost and increase efficiency.Finally,to form a set of optimized liquid flow water flooding technology for the old oilfield with extra high water cut stage.In this study,a single stage sand body structure is analyzed by using reservoir architecture method.To clear the connectivity relationship between interlayer distribution and single stage sand body,and the reservoir architecture model of the delta front of Dongpu depression is established for the first time.The accumulation law of remaining oil under the control of layer architecture is clearly recognized.By means of the flow optimization experiment of the large scale flat model,and the streamline numerical simulation,to obtain the horizontal and vertical sweep laws of the water flooding under the condition of fluid flow optimization.The optimization effect of fluid flow direction is quantitatively evaluated,which provides a theoretical basis for oilfield development adjustment.The results of this study to achieve innovation in two aspects,one is to establish architecture model of delta front reservoir in Dongpu sag;two is a creative application of heterogeneous large size flat model liquid flow optimization experiment,streamline numerical simulation evaluation flow direction optimization effect.