Alaska’s North Slope (ANS) contains a large resource of heavy oil above two of the largest producing fields in North America, but due to the complexity of producing heavy oil in an arctic environment, remains untapped. Development of heavy oil in the Arctic represents a significant departure from conventional oil developments on the North Slope as well as established heavy oil developments elsewhere in the world. This paper describes a cold heavy oil production with sand (CHOPS) test using a surface driven progressive cavity pump (PCP) to evaluate the resource for commercialization. Despite success using this technique in other heavy oil applications, significant design challenges remain. The test recovered significant quantities of oil and sand at minimal drawdown; however, the capacity of the well was limited by surface torque values that were significantly higher then anticipated and ultimately resulted in a rod failure after 3-weeks of production. Further analysis indicated that torque was dominated by drag forces between the continouous rod string and the oil. Followup testing using oil produced from the well was completed with specially designed test equipment to identify the source of the unexpectedly high torque and provided data to improve rod torque prediction. As a result of the work performed, the remaining three wells in the initial pilot were designed with significant upside in capacity.
Due to restrictive surface locations and permafrost, effective solids transport in deviated wellbores and its effect on equipment wear are key considerations that need to be better understood.