Study On Interwell Connectivity And Enhanced Oil Recovery Methods In LD Oilfield

The early polymer flooding is applied on LD oilfield.After a long-term scouring by injected liquid,dominant channel has developed in the reservoir,it caused a sharply rise in water cut and a decline in production.Now dominant channel limits the development of oilfield seriously.Therefore,it is very important to study the reservoir flow field,establish the identification method of wellhead connectivity between reservoirs,determine the connectivity between wells,and study and put forward the corresponding measures to improve oil recovery.(1)In order to analyze the interwell connectivity between LD oilfields,a set of evaluation system for the performance field of flow field strength considering static and dynamic influence parameters was established,and the comprehensive index calculation method,the method of water production,the tracer analysis method,Dynamic connectivity inversion technology and other reservoir engineering methods,the establishment of "contrast" based on the well group,single well high permeability channel identification system to jointly determine the LD oil field within the development of the advantages of flow channel,analysis of the existence of the advantages of flow channel The wells were A10,A23,A35,A1,A7,(2)Research on measures to improve oil recovery.According to the results of early flow field strength evaluation and hyperosmotic channel identification,the improvement of oil recovery scheme is put forward from the point of view of governance plane contradiction and interlayer contradiction and the numerical simulation method is used to predict and verify.Combined with the development of LD oil field,proposed the use of hydrodynamics to solve the two contradictions,chemical flooding method to improve oil recovery: the governance plane contradiction,the current network can be transferred to the row or five-point well pattern;Rising method to adjust the injection structure;governance layer of contradiction,the choice of stratified water injection and the top of the gas injection method.Chemical flooding method can choose foam drive and binary compound drive.Proposed oil field development strategy: the proposed oil field can give priority to the injection structure adjustment,stratified fine water injection,gas and water alternately,2 to 5 years to consider the well pattern reorganization,oil wells injection,the deployment of new wells;oil prices allowed under the premise of 5 years Can consider the binary compound drive,bubble drive and other chemical drive measures.