The Research Of Composition And Adjustment Mechanism Of Polymer Flooding In High-water Cut Well Group Of Y Block

Y Blcck has entered the stage of extra-high water cut.The water content of oil wells is generally higher than 90%.The water cut continues to rise before polymer flooding.The high water cut wells in the block have been characterized by difficulty in achieving results and a low decrease in water cut.Seriously affect the overall development effect of the block.At present,there are many adjustment methods for high water cut oil wells,but the reasons for the formation of high water cut are often ignored.At the same time,the mechanism of high water cut adjustment is not yet clear,and there are relatively few theoretical studies.In order to adapt to the fine development of polymer flooding and ensure that the high water cut wells in the betting block achieve the purpose of increasing oil and water,it is urgent to explore the reasons for the formation of high water cut wells,and to give different types of high water cut well adjustment mechanisms to ensure the development effect of polymer flooding..This paper considers the reasons for determining the formation of high water cut under different permeability conditions,establishes a dynamic and static database of high water cut wells by analyzing the dynamic and static parameters,and analyzes the characteristics of dominant seepage channels.Using the partial flow curve and the relative permeability curve,the relationship between permeability and critical remaining oil saturation at different water cut stages under water flooding conditions is fitted,and the oil saturation under this permeability condition is calculated by numerical simulation and saturated with the critical oil saturation The ratio of the degree is established,and the criterion of high water cut channel is established.The parameters of the proportion of high water cut channels before polymer flooding are divided into different levels,and high water cut wells are divided into four categories,and single type analysis and single factor analysis of variance are used to calculate and identify different types of high water cut wells.According to the characteristics of different types of high water cut well groups,the composition of high water cut wells is analyzed.Using the numerical simulation method,according to the parameters of the second-class reservoirs in the Y zone,the adjustment mechanism of contradictions in,between,and planes of high water cut wells is clarified.According to the characteristics of different types of high water cut wells,the main contradictions of various types of high water cut wells are analyzed,and the adjustment measures of different types of high water cut wells are given to provide theoretical guidance for the optimization of the next high water cut well adjustment measures.By analyzing well pattern factors,injection-production connectivity factors,and injection water volume multiples,the composition factors of high water cut wells are studied,and based on numerical simulation technology,the adjustment mechanism of interlayer,intralayer,and plane of different types of high water cut wells in the target block of Area Y is clarified.The research shows that by establishing the contradiction adjustment model of asynchronous injection-production and water-gathering alternating layers,after the adjustment,the remaining oil that is difficult to be used by conventional water flooding can be effectively used to improve the water flooding sweep coefficient;the establishment of high water cut horizons and intervals Combined adjustment model of contradiction between layers.After adjustment,the problem of inefficient and inefficient water circulation in the high-permeability layer is alleviated.The relative water absorption of the high-permeability layer is suppressed,the water absorption profile of the middle and low-permeability layer is improved,and the vertical sweep volume is increased;An adjustment model for diluting the well pattern and transferring injection plane contradictions was established.After the adjustment of the measures,the pressure balance between the oil and water wells was broken and the flow direction was changed,so that the remaining oil in the areas not affected by the original development plan was affected.