Novel acid diversion technique boosts production

Cantarell Field is the most important complex in Mexico and is the second-largest producing field in the world. Matrix acidizing has always been the main stimulation process used to improve production from the carbonate reservoirs that form the main productive zones, and this is especially the case now that this mature complex has reached its production peak. A critical factor for success of the treatments is distribution of the acid among all productive zones. Since most producing wells are not homogeneous and contain layers of varying permeability, even distribution of the acid is a difficult task. In addition, the water saturation of the various zones has a major effect on the acid distribution. Since acid is an aqueous fluid, it will tend to predominantly enter the zones with the highest water saturation, in many cases resulting in increased water production. This brings with it the multitude of problems associated with high water production.