Production optimization of hydrocarbon reservoirs by entropy generation minimization

Abstract

Reservoir entropy generation has a significant role in production cycles of a hydrocarbon reservoir. During production, entropy generation characterizes the irreversible fluid energy losses. This paper aims to develop a new production strategy that minimizes the entropy production to improve operational efficiencies. The second law of thermodynamics is used to calculate entropy generation in a porous medium during hydrocarbon production. The model considers different sections of a production system, including the reservoir, near-wellbore, and wellbore regions. The proposed model is an extension of the Civan model. The introduced model considers the near wellbore region as a separate zone, which allows flexibility in modelling skin effects near the wellbore. In addition, a new performance criterion, called the coefficient of performance (COP). This COP integrates the recovery factor with entropy generation and provides a quantitative measure to optimize the reservoir production. The model is used to conduct a parametric sensitivity analysis including effects of fluid and rock parameters such as permeability, porosity, viscosity, skin factor, and temperature on the total entropy production. The COP is used to optimize operating conditions of the reservoir such as production rates and bottomhole pressure. It was found that permeability and the bottom hole pressure have the most impact on the total entropy production. This article will present new approaches and findings to maximize the recovery efficiency by minimizing entropy generation of fluid transport processes in a hydrocarbon reservoir.