The purpose of this paper is to investigate the impact of flowback strategy on Permian unconventional wells' short-term production and long-term performance, and subsequently to optimize flowback strategy to balance production and cost to achieve the best asset value. Multiple methodologies including early productivity trends, oil Estimated Ultimate Recovery (EUR), Rate Transient Analysis (RTA), and simulation were applied to evaluate the impact of flowback strategy on well performance. The impacts on both short-term production and long-term performance as well as the cost analysis of different flowback strategies were integrated for economic evaluation.
An aggressive flowback strategy can speed up the production rate tremendously early in the life of a well. Different flowback strategies have minimal impact on the long-term performance of wells with modern completion designs, but they may have a potential impact on small completion designs in the Permian Basin examples. However, aggressive flowback is also associated with higher capital and operating costs. Integration of production performance analysis and cost estimation is necessary to achieve the best value for the field.
The findings of this study have been successfully applied to Permian unconventional Bone Spring Sands and Wolfcamp wells in many fields. Different fields and benches can have different optimal flowback strategies based on reservoir potential and the associated flowback cost. Flowback guidance for different fields and benches has been developed for the operations team to follow. The optimal flowback strategy has improved the field value by either significantly accelerating early production or reducing costs for each individual field.
One of the primary ways to influence a well's production during flowback is the speed of drawdown. The speed can be controlled by opening the choke valves and by the size of the flowback setup capacity (one-train or multi-train flowback). When considering a flowback strategy, the balance between short-term production and long-term performance should be optimized; facility selection should also have a balance between short-term production and associated cost. These balancing acts drive operators to change and experiment with different flowback strategies using choke management on a regular basis to optimize cash flow and net present value (NPV).
