Developments in nondamaging, degradable diverters with outstanding plugging efficiency have opened new opportunities for protecting existing fractures by plugging them and then fracturing zones that were previously bypassed because of inefficient zone coverage or refracturing zones that were inefficiently fractured initially. With multistage operations becoming the industry norm, operators need easily deployable diversion technologies that will protect previously stimulated perforations and enable addition of new ones. This paper reviews several aspects of the use of in-stage diversion.
Polymer-based degradable diverters are temporary materials that are useful in some oil and gas operations, primarily to enable fluids to flow into areas of the reservoir where fluid dynamics would normally exclude them. While standard mechanical diverters work well for zonal isolation, they must be physically removed from the well after the workover job has been completed.
Degradable diverters have performed an important role for many decades, but they cannot meet operational requirements to stay intact for weeks or even hours. Perforation balls or degradable ball sealers will fall away from perforations without continuous application of pressure. Rock salt and flakes will dissolve after a few hours. High temperatures degrade the material faster....
Enhancing Well Performance by In-Stage Diversion in Unconventional Wells
01 July 2017