A New Generation Chemical-Flooding Simulator

Abstract

Summary Compositional reservoir simulators that are based on equation-of-state (EOS) formulations typically do not handle the modeling of aqueous phase behavior, and those that are designed for modeling chemical processes typically assume simplified hydrocarbon phase behavior. There is a need to have a single reservoir simulator capable of combining both approaches to benefit from the advantages of both aqueous and hydrocarbons models. Developing and implementing fully implicit procedures for modeling both hydrocarbon and aqueous phase behavior simultaneously is a complex process. An approach to integrate a surfactant phase behavior model into an existing fully implicit, parallel, EOS compositional simulator is presented in this paper. Physical property models describing the flow and transport of surfactant and polymer species have been implemented. These properties include surfactant phase behavior, interfacial tension, capillary desaturation, viscosity, adsorption, and relative permeability as a function of trapping number. Polymer properties include viscosity, permeability reduction, inaccessible pore volume, and adsorption. The simulation results were validated by comparison with the explicit chemical-flooding simulator UTCHEM and are shown in this paper. Test runs were performed with high-resolution models in a parallel environment, with results indicating a good scalability of the simulator.