Optimizing acidizing design and effectiveness assessment for horizontal wells

The success, safety and stability of treatment methods of bottomhole formation zone depend on adequate bottomhole pressure. The latter is not directly controllable, but it can be changed by adjusting injection pressure. Using the Paccaloni method for any given measured injection rate, the downhole injection pressure can be estimated. In this paper, the Paccaloni method was developed, and the pressure drop changes in the skin zone for horizontal and vertical wells were estimated for planning acid treatment of the bottomhole formation zones in vertical, deviated and horizontal wells. To model pressure and velocity distributions in the bottomhole zone for the case of water injection in a vertical and horizontal wells COMSOL Mathphysics modules were used. Keywords: bottomhole pressure; reservoir pressure; acid treatment; Paccaloni method; permeability; flow rate.