Industry continues to struggle with acid distribution and penetration. Most papers, therefore, continue to focus on these themes. Other than recommendations for further reading, a few other papers are worthy of mention and may provide some useful tools for the practicing engineer.
Paper SPE 214416describes a novel technique that could perhaps be developed further. The concept is built around running a tool on wireline across the zone of interest, which, upon activation, generates hot acid vapor. The procedure is simple, bearing a low cost with no associated environmental hazards. Engineers desperately need an alternative to acid placement through pipe, coiled tubing, or bullheading. For example, propellants have been around for years; however, their performance has not quite met the hype. Nevertheless, several case histories have been authored to suggest their efficacy; historically, some treatments have even been wildly successful. The point is, more effort is needed to mature techniques such as these as an alternative to conventional stimulation.
In paper URTEC 3818857, an oxidizer is introduced as a preflush to improve near-wellbore conductivity without adding significant cost and operational complexity. The oxidizer was effective in removing biological debris and biofilms, thereby improving acid penetration. Paper SPE 215664 examines the use of biodegradable particles and fibers to divert in naturally fractured carbonates. Size distribution was the key to achieving temporary isolation with a minimal amount of material. In fact, the paper showcases successful treatments with less than one barrel of this material. Furthermore, no material was recovered during flowback, indicating complete degradation.
Lastly, SPE 216144 introduces a novel automated framework that relies on smart sampling and tests multiple scenarios to arrive at an optimal stimulation design. The process is intelligent and entirely Web-based.
Acid stimulation is indispensable, and the understanding of fluid systems, and the placement thereof, continues to evolve.
This Month’s Technical Papers
Limited-Entry-Liner Well Stimulated Effectively With a Viscoelastic Diverter-Acid System
Model Captures Carbonate Matrix Acidizing in Horizontal Well Completions
Nanoparticle-Based Fluids Reverse Long-Term Hydrocarbon Decline
Recommended Additional Reading
SPE 218353 From Zero to Hero: A New Breakthrough of Stimulation Method by Combining Acidizing and Cyclic Extended Breakdown in Sawah Field by Ilfi, PT Pertamina, et al.
SPE 214821 How Downhole Conditions Impact Acidizing Performance in Carbonate Reservoirsby M.A. Sayed, Saudi Aramco, et al.
SPE 215332 Novel Single-Phase Retarded Acid System for Effective Stimulation of Limestone Reservoirs by Mohammed Qamruzzaman, ONGC, et al.
Imran Abbasy, SPE, is the managing director and chief executive officer of Pakistan Petroleum Limited (PPL). He has over 35 years of global industry experience with leading E&P companies, having held technical and leadership roles in production technology, drilling, completion engineering, and operations. He has worked in the North Sea, Middle East, Australia, Indonesia, Nigeria, and Papua New Guinea, supporting completion design, artificial lift, well integrity and production optimization. Abbasy is leading PPL’s transformation to an international energy company, with a strong presence in the mining sector. He also manages or chairs PPL’s associated companies, overseeing operations in offshore Abu Dhabi and the Reko Diq copper and gold mining project. Abbasy has authored several SPE papers and has participated in SPE Applied Technology Workshops. He holds a bachelor’s degree in mechanical engineering and a master’s degree in aerospace engineering from George Washington University.
