DETERMINING OPTIMIZED GAS INJECTION RATE FOR GAS LIFTED WELLS TO MAXIMIZE LIFT EFFICIENCY

Problem being addressed: Determining optimized Gas Injection Rate for Gas Lifted wells to maximize lift efficiency. Challenges: While Gas Lift is the most natural artificial lift method, ever-changing surface and downhole conditions cause significant inefficiencies. The changing conditions require frequent adjustments to surface-injected gas rates to maintain the most efficient lifting gradient. If the proper adjustments are not made, these inefficiencies may hinder production and increase lease operating expenses. Solution: By using Apergy’s proprietary hunting algorithm, Bloodhound, optimal gas injections rates are determined by the magnitude in the bottom hole pressure drawdown, with use of a permeant down hole gauge. Through continuous and proportional rate adjustment, the Bloodhound algorithm learns from previous set point deltas and tests against the inferred optimal rate, as well as changing conditions. Results: In under-injection scenarios, Bloodhound can accelerate the recovery of oil by up to 10 percent, regardless of the well’s position on its natural decline. In over-injecting scenarios, wells can maintain oil production rates while using up to 50 percent lift gas. Both results can be successfully achieved with few engineering hours, manually calculating or modeling well performance curves to determine inferred optimal rate.