Projected gas production is a critical variable in well planning, and the downhole tools chosen for gas mitigation are vital to production performance. With sucker rod pumps, inefficiencies due to gas presence can reduce the time between pulls and negatively affect production rates. The packer-style gas separator (PSGS) has higher-liquid-volume capabilities than "poor-boy" gas anchor style tools. Packer-style gas separators have become an industry-recognized tool used to increase production in gaseous fluids on rod-lift wells by using volume restrictions to create pressure changes then filtering the free and entrained gases from liquids.

This study examines the operational parameters involved in the use of a PSGS in downhole gas separation. A flow loop laboratory test was conducted to evaluate the separator's qualitative properties. Additionally, two separate case studies were analyzed to understand the impacts of downhole gas separation on production rates, pump run time, and pump fillage.

The laboratory experiments used a transparent model in the flow loop for a visual analysis of the separation occurring during operation. A water-nitrogen solution of varying concentrations was run through the separator to examine drawdown parameters during inflow. The results showed that at 95% liquid capacity, the nitrogen inflow was successfully contained within the modeled tubing-casing annulus, preventing entry of gas into the simulated pump intake.

Two case studies were recorded in separate geographical regions to verify operational success. In south Texas, an operator successfully mitigated gas from five high-GLR wells. The PSGS in each well successfully separated 300 to 500 Mcf per day of gas from tubing production inflow. As a result, the total fluids output increased by up to 200%. In west Texas, an operator used the separator in nine different wells. On average, the fluid production increased by 61%, pump fillage increased by 11%, and pump run time increased by 33%.

Overall, through laboratory and field testing, the PSGS has proven its ability to handle a wide range of downhole conditions. By improving downhole gas separation before fluid enters the pump, gas interference effects are mitigated and overall rod lift system efficiency is enhanced.

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