Synthesis of the Optimal Scheme Polymer Flooding with Constraints on the Bottomhole Pressure

Abstract

The method of control synthesis for optimal development of oil fields with use of polymer flooding method to increase oil recovery is described in this paper. The main purpose is to maximize the economic effect and decrease special equipment operational loading. The base of the approach considered is minimization of the quadratic functional with Gauss-Newton method. The minimum of the functional corresponds to the economic effect wanted: maximization of the volume of recovered oil with minimal volume of used polymer. The method includes special bottomhole pressure constraints processing due to technological capabilities of the special downhole equipment. When building the optimal scheme high quality digital models of the field are used with the method of numerical modeling of multiphase flow in porous media that takes into account complex physical processes taking place in the reservoir when EOR methods are applied. Computational experiments have been provided on the model obtained as a result of well data adaptation. Three versions of optimized five years development scheme have been built: with no constraints on the bottomhole pressure and with limitation of 250 and 200 atm. The experiments results have shown that the use of synthesis allows gaining wanted economic effect including under the given constraints due to decreasing of the special equipment operational loading.