Study On The Strategy Of Injection-production Pattern Adjustment In Offshore Oil Field

In the development of offshore oil field,wide well spacing,multilayers and high recovery rate of production methods will be used,which aggravated the discrepancy of the development of horizontal and vertical reservoir stratum.Therefore,it is necessary to study the law of fluid flow in the horizontal and vertical reservoir stratum during the offshore oilfield development.The streamline method allows us to understand the distribution of underground fluid,more intuitively understand the law of water flooding in each layers,and provide a strong basis for reasonable adjustment of injection and production well pattern.Based on the investigation of a large number of literatures at domestic and abroad,this paper studied on the research of the streamline method,and established the mathematical model of the injection-production pattern,which consider of the rheology of the crude oil in high permeability sandstone heavy oil reservoir,and the process of the streamtube model solution is given.To analyze the rheology of the crude oil,the viscosity of the crude oil,well spacing,and injection-production pressure difference effect on the distribution of the streamline and the law of lateral flooding.Based on the development characteristics of the multi-layer in the offshore oilfield,established a multi-layer development displacement model based on the streamtube method,analyzed the interlayer inhomogeneity,the viscosity of the crude oil,the number of oil layers and the pressure difference influence on difference in the development of multi-layer,and compare the development effect of different single factor under different value conditions,and then determine the different single factor of the stratified development of technical boundaries.On the basis of this,the numerical simulation streamline model which is used to adjust the injection-production pattern is established by using streamline numerical simulation technology,the size of the distribution of the streamline under the condition of the basic well pattern is analyzed,and the adjustment strategy of the injection and production pattern in different stages is determined.The application of the adjustment strategy of the well pattern increased the area sweep of the low permeability oil layer and improved the overall development effect of the oil field.By studying the law of multi-layer water flooding,the boundary of the offshore oilfield stratification development is obtained.The boundary of the permeability difference is 8,the boundary of the crude oil viscosity difference is 5,and the stratified boundary of the oil content is 8.The application of plane well pattern adjustment and vertical well pattern adjustment strategies can effectively reduce the discrepancy of water flooding in the development of multi-layer,and significant improve the plane and vertical oil layer development effect,which has a suggestion meaning to the efficient development of offshore oilfield in high production and the reasonable adjustment of well pattern in late development.