Artificial Lift: Adapting to Change

Abstract

_ Humans and oil are alike in that the inner will to move from a comfortable spot—be it a sofa or a shale pore—often requires the application of outer motivation. It could be the hunger pangs prompting a reach for a donut or the pesky roommate—natural gas—lifting the hefty crude bead on its way to the surface in response to a pressure differential. So, what is a human to do when the oil needs a little extra convincing to leave its sofa? Artificial lift has long provided the swift kick needed to get and keep oil moving in conventional resources. Its story in unconventional resources is one of countless hours spent in the field figuring out that what works in one basin may not necessarily work in another and that what works today to economically lift oil to the surface will change over the life of the well. In this first part of a two-part series, we look at how the artificial-lift sector has adapted to producing unconventional resources. The second part of the series to publish in November will crack open the lift toolbox to take a deeper look at the techniques and technologies under development or new to the market. Steep Learning Curve While the life cycle of conventional oil and gas development is well documented, the rush of unconventional wells that kicked off in 2009 brought with it a whole slew of new challenges, like highly tortuous wellbores and solids production, spurring a greater appreciation for the intricacies of field development. “There was a steep learning curve in the early stages of producing from unconventional reservoirs. As operators continue to develop these reservoirs and push the envelope by drilling longer laterals with more-complex deviation profiles, artificial lift must keep adapting,” said Thomas Anderson, vice president of rod-lift solutions and PCS Ferguson at Champion X. “What worked last week needs to be tweaked to perform even better to handle the challenges we’ll face next week. It’s a constant evolution and we’re continually working to evolve our fit-for-purpose technologies, processes, and services to meet tomorrow’s challenges.” The remarkable growth of the US shale industry over the past 13 years has been, in part, built on the foundation of conventional oil and gas techniques and technologies. “Existing lift methods have been redefined based on newer production challenges not present in traditional vertical wells. Well geometry, landing depth, tight casing size, longer lateral draining higher production rates, and increased oil/gas rate are just a few of the new challenges in unconventional wells,” said Humberto Machado, global product line director for artificial lift at Weatherford. “The lesson learned here is the integrated planning and the development of an artificial-lift strategy that allows scalability, rapid deployment, robust and simple to operate, minimal infrastructure, and ability to match decline curve. This requires significant trial-and-error efforts to develop best practices, and operational guidelines to enhance overall system reliability,” he added. This redefinition, along with a little adaptation, and a whole lot of experimentation has developed a new toolbox unique to its role in the production process.