Performance of Polymer Injection in Hydraulically Fractured Heterogeneous Reservoirs - A Simulation Approach

Global energy demand is increasing annually and enhancing oil recovery (EOR) from mature reservoirs is of crucial importance. Polymer flooding is a favorable chemical EOR method because of its impact on sweep efficiency. Polymeric fluid is used to drive water within bypassed regions since they are responsible for water viscosity increment and its relative permeability reduction. A high viscosity polymeric fluid improves mobility ratio, reduces viscous fingering, as a result enhances areal sweep efficiency. A challenging problem of polymer flooding is the impact of shear rate on viscosity of polymeric fluid which is undoubtedly of concern for injectivity issues. Polymer flooding above FPP (Field Parting Pressure) is a solution that creates and propagate induced fractures, as a result injectivity goes up. Impact of induced hydraulic fracturing on shear rate and injectivity is a special topic for polymer flooding case. In this study the effect of induced fractures on injectivity of polymer injection wells will be investigated using two different homogeneous and heterogeneous models. Firstly, simulation model will be discussed briefly. Then results of different scenarios are described. Effect of hydraulic fracture is presented homogeneous and heterogeneous reservoirs (areal and vertical heterogeneity).