Study On The Reasonable Time Of Following Water Flooding For Two Types Of Oil Reservoirs In X Block

Block X has implemented and promoted the second-layer oil polymer flooding since 2007.The second-layer oil layer has a single layer with thin thickness,strong heterogeneity,low permeability,small scale of sofa training,and poor sand body connectivity.Through the fine adjustment of oil and water wells in recent years,the polymer flooding of Class II oil reservoi rs has achieved good development results,but there are still some problems such as unbalanc ed utilization of some oil layers,large amount of polymers,and poor development efficiency.The study of residual oil distribution during the polymer flooding stage of the second oil layer,reasonable timing of subsequent water flooding by the polymer flooding drive,and optimum injection rate in the subsequent water phase are important for improving the recovery factor of the second type oil layer in the polymer flooding stage and further tapping remaining oil.In this paper,the optimal limits of the subsequent water flooding of polymer flooding in Type II oil reservoirs are studied.The results of the optimal timing for the second water flooding of the second oil reservoirs are verified by the numerical simulation.The design is transferred to different water cut stages for subsequent water flooding.Injecting parameters for polymer solution flooding,conducting indoor physical simulation experiments,and studying the optimal timing of subsequent waterflooding by three-pipe parallel experiments and three-layer heterogeneity flooding experiments,and given the optimal water cut limit for subsequent waterflooding.And the amount of polymer limit.In order to achieve high-yield and high-efficiency development of oilfields,numerical simulation methods are used to simulate and predict the timing of subsequent waterflooding in different water-bearing stages.The differences in the water-supply rise speeds of different water-bearing stages to subsequent waterfloods are studied,and the transitions to different water-bearing stages are carried out.The economic benefits of subsequent waterfloods are evaluated as the main indicator for determining the optimal timing for the subsequent waterflooding of the injection block,and the water cut limit of the subsequent waterflood is preferably selected.