Novel Numerical Simulation Modeling and Coreflood Experiments of Acidizing of an Iranian Carbonated Gas Reservoir

Abstract

Summary Acidizing is a stimulation treatment which significantly improves production rate particularly in the carbonate reservoirs. However, the evaluation of this treatment requires performing extensive laboratory experiments. A tuned mathematical model, capable of describing the acidizing in the core-scale, can play a vital role due to the high expenses of the required experiments. Equations from different areas have been combined to develop a model which simulates the flow of the acid in the porous media accurately. The model, a cross-link between three different scales: pore, Darcy, and core; considers the effect of convection, diffusion, and chemical reactions. In this study a complete package including acid core-flood experiments, X-ray imaging and numerical simulation of the wormhole propagation was performed. The core-flood experiments were performed on the core samples from a gas reservoir. The X-ray imaging technique was employed to evaluate the results of acid core-flooding. A model was developed in a FEM-based software with the same properties of the cores. The numerical model allows simulating the wormhole propagation process. Both simulation and visualization of the wormhole propagation of acid core flooding experiments are presented. A very good agreement between experiments and simulation was observed.