High-Pressure Gas Lift System Performance and Efficiency Optimization Through Dual Two-Stage Compression Design

Abstract

Since its introduction in 2017, High-Pressure Gas Lift (HPGL) has proven to be an efficient method for lifting wells during early production life. The production rates achieved are comparable to, and in many cases greater than, those obtained with Electric Submersible Pumps (ESPs). Since its inception, booster technology has advanced significantly in terms of efficiency, lease operating expenses (LOE), and emissions reduction. Two-stage booster systems can achieve discharge pressures ranging from 1,500 to 5,500 psi, enabling wells to be unloaded and produced through a single-point injection at the end of the tubing. One booster model has been deployed in more than 1,000 installations across the United States, consistently delivering successful results. It is typically applied to single-well configurations, utilizing a unified two-stage compression system with a single discharge point. A more recent booster design introduces dual two-stage compression systems and dual discharge points, both powered by a single engine. This configuration improves efficiency, particularly in multi-well applications. Ovintiv has deployed 22 two-stage boosters to support 64 wells in Oklahoma, yielding positive results. These boosters are typically installed for five to six months following initial flowback, until tubing pressure declines to approximately 900–1,000 psi. During this high-pressure production phase, the wells operate on annular flow, with gas injected down the tubing string and production flowing up the tubing-casing annulus. Once the pressure drops, the wells transition to single-point injection using a standard three-stage compressor. Subsequently, they are switched to tubing flow, utilizing a conventional gas lift system. Two of these wells were analyzed to review historical performance and identify potential areas for improvement. Comparison with Nodal analysis modeling indicates that actual production rates line up with modeled values. To understand where further improvement may be possible, the compression system must be reviewed to assess opportunities for greater efficiency in gas injection delivery, particularly during the initial months of HPGL operation under annular flow. When evaluating system efficiency, the primary concern is fuel consumption—specifically, how to reduce it without compromising performance. Converting to a dual two-stage booster can achieve a leaner system by operating two compression systems powered by a single engine, thereby reducing fuel usage and overall monthly operating costs by approximately 25%. An additional benefit of reduced fuel consumption is the corresponding decrease in emissions, which is an increasingly important factor under current environmental regulations. The combination of utilizing dual compression systems along with single compression systems in multi-well applications can improve efficiency by providing savings on LOE, whilst also providing emission reductions