Particle swarm optimization of thermal enhanced oil recovery from oilfields with temperature control

Abstract

Thermal enhanced oil recovery (EOR) methods are commonly used to extract heavy oil from oilfields. Hot water injection into reservoirs reduces oil viscosity and increases its mobility to move toward production wells. Water flood EOR projects are traditionally implemented with rate and bottom-hole pressure (BHP) control of injection and production wells to recover more oil from reservoirs. Whereas, water injection temperature can also play an important role in overall oil recovery, especially in sandstone rocks in which the relative permeability is a function of both the temperature and saturation. The present study aims to optimize hot water injection process in heavy oilfields using particle swarm optimization (PSO) approach. Effects of water injection temperature, and the water injection rate and BHP of producers are investigated on cumulative oil production of heavy oil reservoirs. First, through optimization of the hot water flooding process in a 2D heterogeneous reservoir with 13 wells, it has been shown that optimal values exist for the water injection temperature of different wells. Secondly, the idea has been tested in a 3D field reservoir successfully. Results show that PSO can properly be implemented for optimization of hot water injection projects. Furthermore, optimal control of water injection temperature can improve oil recovery.