Modeling the acidizing of a carbonate formation

Two approaches to the determination of the optimum conditions of the well bottom zone treatment in a carbonate formation are considered and compared. The first, bench approach is based on the investigation of the process of wormhole formation in rock cores, while the second approach is the mathematical modeling of the process within the framework of mechanics of multi-component seepage flows using averaged values of the reservoir porosity and permeability. A mathematical model of the process, that takes account for fluid flow and the chemical reaction between the acid and the rock matrix proceeding in the kinetic regime, is presented. Both approaches indicate the existence of an optimum rate of acid solution injection into the formation at a certain given value of the dimensionless Damkoller number.