Using Analytical Solutions in Compositional Streamline Simulation of a Field-Scale CO2-Injection Project in a Condensate Reservoir

Abstract

Summary This paper applies compositional streamline simulation to model a real field-scale project that is a combination of enhanced condensate recovery and geologic storage of CO2. These processes are inherently compositional, and detailed compositional fluid descriptions must be used to represent the displacement behavior accurately. We demonstrate that compositional streamline simulation, along with the use of analytical solutions for condensate displacement, is computationally efficient enough to permit high resolution of spatial heterogeneity as well as detailed characterization of the fluid system. We present a simulation study comparing streamline and finite-difference results for 2D and 3D examples to demonstrate that the compositional streamline method is an efficient computational method for modeling CO2 storage and condensate vaporization in gas reservoirs. Although the streamline method makes many simplifications regarding the effects of gravity and capillary crossflow, in heterogeneity-dominated systems such as the condensate system presented, comparison of finite-difference and streamline results confirms that these simplifications are reasonable.