A real-time virtual monitoring system of the skin factor for matrix acidizing treatments

It is known that oil well productivity can be correlated with the quantification of the damage to the formation (skin factor) and that oil well stimulation through acidizing treatment may be used to improve the permeability of the well pore and restore oil productivity. Current monitoring systems of the skin factor have focused on acid treatments with a single-phase, in which the determination of skin factor is carried out via simplified models in a closed-form, avoiding the need for a real-time platform. However, the combination of several injected fluids is a common procedure in matrix acidizing treatments, giving rise to the formation of foams and two-phase flow. In this case, the real-time estimation of the skin factor requires robust models whose numerical solution should be synchronized with the dynamics of the matrix acidizing treatment in a real-time platform.This paper presents a real-time virtual monitoring system in the wellbore of an oil field to monitor the evolving skin factor during gelling foam acidizing treatments, in which the estimation of the skin factor is conditioned by real-time constraints. The system performance is evaluated using field data available from the stimulation treatments in oil wells located in southeast Mexico. The output results indicate that the real-time virtual monitoring system can successfully predict the evolution of the skin factor. This information is useful for the control and optimization of matrix acidizing treatment.