The Property Analysis And Flooding System Design Of Ultra-high Molecular Weight Viscoelastic Polymer

Ultra-high molecular weight viscoelastic polymer flooding system is one of the polymer flooding systems,which uses viscoelastic properties of ultra-high molecular weight polymer and can also compound with surfactant and PPG.The major displacement mechanism is to improve oil displacement efficiency of polymer flooding by using the ultra-high molecular weight polymer viscoelastic effects,which can be effectively applied to heterogeneous reservoir after polymer flooding to improve oil recovery.Based on the reservoir characteristics of the increasing permeability after polymer flooding,the increasing coefficient of variation,the increasing reservoir heterogeneity,and the more scattered distribution of remaining oil in a block of Shengli oilfield,viscoelastic flooding system is optimized by the laboratory experiment and field test.The basic physical and chemical property,increasing viscosity,viscoelasticity,rheological behavior,seepage and the displacement property of ultra-high molecular weight polymer are studied through the laboratory experiment.Based on the study of the interaction of surfactants and ultra-high molecular weight viscoelastic polymer,the binary compound flooding system of ultra-high molecular weight viscoelastic polymer is designed and the properties are evaluated.Through the screening of PPG samples and the evaluation of suspension property,viscoelastic peroperty,injection performance,plugging performance and adjusting the heterogeneous property,the reinforced polymer flooding system of ultra-high molecular weight viscoelastic polymer is designed.In order to determine the adaptation and feasibility of the reservoir of ultra-high molecular weight viscoelastic flooding system,the sensitivity analysis of the reservoir has been analyzed.Injection test is conducted according to a block of Shengli oilfield,in order to determine the field viscosifying capacity and injection property of ultra high molecular weight viscoelastic polymer flooding system.And the adaptability of polymer flooding reservoir has been evaluated.The single-well injection test program and a detailed monitoring program also have been designed.