Maximizing Well Deliverability in the Eagle Ford Shale Through Flowback Operations

摘要

Flowback procedures for wells producing from sub-normally or normally pressured reservoirs are usually straightforward and non-technical due to the short flowing periods that are inherent with low pressure wells. Over-pressured formations can naturally flow for several months and even years. However, uncontrolled procedures can potentially affect the well productivity and its profitability. Flowback techniques for wells flowing from over-pressured reservoirs can vary widely and have a significant impact on short and long term economic performance. This paper focuses on the evolution of flowback operating procedures for wells in the Eagle Ford shale play and highlights how these procedures can impact short and long term well performance. The workflow demonstrates how choke management, or drawdown strategies, can influence potential damage mechanisms in the reservoir, completion and wellbore. Techniques are then presented for using rate transient analysis (RTA) that allows for a robust understanding of early time well performance while also monitoring for damage downhole. The data shows that using RTA with high frequency data to help drive operational decisions during the flowback period can deliver optimal drawdown procedures and maximize well deliverability. This in turn maximizes time sensitive economic metrics by taking full advantage of variables like the well’s completion efficiency and stimulated volume. The drawdown management workflow outlined in this paper has proved to significantly outperform predetermined choke procedures that have historically been common practice in industry. Results also show how practical field applications of technical interpretations can be used on a daily basis to significantly increase value and drive operational efficiencies in the field while minimizing the potential risk of damaging the completion.