Zero-Damaging Stimulation and Diversion Fluid: Field Cases from the Carbonate Formations in North Kuwait

Abstract

SummaryThe high permeability contrast seen in the producing zones of the oil wells of the north Kuwait Mauddud formation makes the uniform stimulation of this carbonate formation a challenge. To achieve diversion, polymer-based fluids were used earlier but with limited success. Recently, a nonpolymeric system containing a viscoelastic-surfactant-based (VES) self-diverting acid (SDA) was used to divert and effectively stimulate entire pay zones with great success.Production logs run before and after the stimulation treatments indicate stimulation of the entire perforated intervals. Stimulation using this new system on the first 17 wells resulted in a production increase of approximately 30,000 BOPD—much higher than that expected from conventional treatments. The wells that were not producing earlier after several conventional treatments are now producing naturally after treatments using this nondamaging system. Nearly 100 wells in the same reservoir were treated with this system after successful introduction of the technology. The use of this technology is now extended to matrix stimulation of gas producers, water injectors, and disposal wells.