Well control optimization considering formation damage caused by suspended particles in injected water

Water flooding is one of the most important technologies to enhance oil recovery. An important task in water flooding is to determine optimal well control. Caused by suspended particles in injected water, formation damage always occurs during water flooding, thus leading to injectivity decline. Higher injection pressures, which may over the maximum injection pressure the surface facilities can provide, are needed to realize well control strategy. However, little attention has been paid to formation damage during well control optimization. In this work, we develop a method to optimize well control considering formation damage caused by suspended particles in injected water. We predicted the effect of formation damage on the well production performance by coupling an analytical model with a reservoir numerical simulator. Then a well control optimization model subjected to injection pressure constraint is built and solved by the Covariance Matrix Adaptation Evolution Strategy (CMA-ES) algorithm. The applications of our method in a five-spot model and an Egg Model justify its effectiveness. Results demonstrate that the formation damage caused by suspended particles in injected water cannot be ignored during well control optimization. The method developed here provides a more practical well control strategy by considering formation damage during the process of optimization. (C) 2016 Elsevier B.V. All rights reserved.