Practices and Experiences of Seven-Year Polymer Flooding History Matching in China Offshore Oil Field: A Case Study

Abstract

Abstract Pilot test of hydrophobic associating polymer flooding has been applied in SZ36-1oil field for seven years, which has shown a quite good trend of water reducing and oil increasing. Understanding of polymer injection reservoir as well as the optimization of polymer injection program needs the help of history matching of numerical simulation, the key point is the selection of the values of polymer physicochemical parameters, which dues to the difference between laboratory experiment conditions and underground reservoir flow conditions, the values of polymer physicochemical parameters obtained from laboratory experiments are ideal. Therefore, this paper carries out a brand-new history matching method for polymer flooding, that is, a water flooding model, which reflects really to the actual underground reservoir, is obtained by history matching, which bases on the understanding of 17 years water flooding and combination of static and dynamic data, and then according to dynamic reflection of polymer flooding which lasts seven years, modifying the values of polymer physicochemical parameters and static model, so a polymer flooding model and a set of reservoir-scale physical and chemical parameters(viscosity-concentration relationship, residual resistance factor, adsorption curve, inaccessible pore volume) can be obtained. Based on the production performance of this pilot test area, the polymer flooding tracking simulation is made for the purpose of timely adjustment of the physical and chemical parameters of the polymer, allowing them to approach the real situation and obtain the optimum effect of polymer flooding.