RESUMO

Formation damage reduces well production or injection capacity, and the removal of damage is one of the major goals of petroleum engineers. Matrix acidizing can significantly enhance the productivity of a well when near-wellbore formation damage is present. In this treatment, acidic solution is injected to the well at pressures below the rock failure pressure. Acid can dissolve minerals in the formation and consequently recover or increase the permeability in the near-wellbore region. In successful carbonate acidization, acid can create empty channels called wormholes. During production, wormholes become pathways for the reservoir fluid to reach the well and hence improve production. In this work, matrix acidization in the multilayer carbonate reservoirs has been simulated in 3-D radial flow. The model includes nonlinear chemistry at the solid−fluid interface, depending on the reservoir temperature. The effect of rock composition in each layer and reservoir temperature on the final skin factor and dissolution patterns has been investigated. Also, the effects of temperature and concentration on acid viscosity and density have been considered. A good agreement is found between the simulated and field data.