NCG (Non-Condensable Gas) co-injection with steam has been in operation at Surmont SAGD field since 2017. After a significant number of operational attempts to mitigate ESP no flow events (deadheading) suspected to be instigated by increased production of gas (typical SAGD GOR 5-10 m3/m3) a strategy was developed to focus on completion adjustments to the ESP on candidate SAGD producers. These changes were completed in late 2019 to help reduce the loss of production, which could impact viability of NCG co-injection at Surmont. Three separate completion adjustments were made: an inverted shroud installation, a larger OD pump with a gas separator, and lowering of an ESP to the lowest possible TVD.

A comparison of the production and operational performance before and after each completion adjustment was completed. In-depth design reviews between CPC and the equipment vendor were done to ensure maximum chance of positive benefit. The inverted shroud installation was expected to improve gas separation efficiency, leading to a reduction in the frequency of No Flow Events (NFEs), which were impacting production rates. The shrouded ESP performance on the first candidate well showed no NFEs with a significant increase in production rates compared to the baseline before the completion adjustment. The larger OD pump with gas separator install was also expected to reduce or completely prevent NFEs. the results were also positive, with an increase in production and no further NFEs recorded. Lowering of a third ESP to a point as close as possible to the liner hanger did not achieve any long-term change in production performance. With the success of the inverted shroud, a second installation was completed on the third well where the ESP was being lowered. A production increase and prevention of NFEs were documented like the first shroud installation, confirming the benefit of the shrouded ESP design. The completion changes confirmed that suitable adjustments to mitigate the effects of NCG injection are possible, with further development on design required to optimize for production capacity and long-term performance.

With the results seen so far, further installations will be completed in the future on appropriate candidates to continue to mitigate the effect on ESPs of produced NCG volumes.

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