Study On Adjustment Method Of Improving Development Effect In Sp Flooding Stage Of J Oilfield

Due to the strong heterogeneity of reservoir in J oilfield,there are a series of problems in the process of chemical flooding development,such as uneven water injection profile,polymer crossflow,high water injection pressure,lack of injection,and sharp drop of liquid production capacity after the oil well takes effect,which seriously affect the effect of precipitation and oil production.After the implementation of SP flooding pilot test,some oil production wells have a significant drop in liquid production,while facing serious problems such as polymer plugging,sand plugging,pollution and so on,resulting the development effect of SP flooding is getting worse year by year,so it is urgent to carry out further technical research to improve the development effect of chemical flooding in J oilfield.In view of the problems existing in SP flooding stage of J oilfield,this paper uses the geological characteristics and development dynamic data of J oilfield for numerical simulation study,analyzes the distribution characteristics of remaining oil in the study block,and clarifies the development potential.Combined with the development characteristic parameters of SP flooding stage,this paper analyzes the main problems existing in SP flooding stage,and puts forward corresponding adjustment methods.At the same time,according to the analysis results of reservoir development status after SP flooding,experimental research was carried out to determine the reasonable reuse technology scheme of residual polymer.The results show that the distribution of remaining oil in J oilfield is complex and diverse,scattered on the plane,mainly concentrated in the area of non mainstream line;vertically,mainly concentrated in the interval with relatively low permeability and relatively small thickness,with great potential for further development.In view of the problems in the development stage of SP flooding,such as the decrease of oil well liquid production,high water injection pressure,lack of injection,the effectiveness of plugging removal measures for oil and water wells is predicted.It is predicted that the cumulative oil production of a single well can increase by up to 0.16×10~4m~3 after the well is unblocked.After the well is unblocked,the oil production of the surrounding wells will increase by up to 0.98×10~4m~3 in the whole area;Aiming at the problem of mutual interference between water drive and SP drive,the results show that at present,the control effect of comprehensive binary injection on 16 wells in infill well pattern is the best,and 0.53%higher EOR than no adjustment plan.The experimental results of the fixation technology of the underground residual polymer and the flocculation technology of the formation residual polymer show that the recovery can be increased by 12.46%by injecting 0.2PV fixative on the basis of the water flooding after the polymer flooding,and the plugging effect of the polymer and the flocculation system is obvious under the lower polymer concentration,which provides the theoretical support for the further enhanced recovery technology after the binary composite flooding.