Water Shut-Off Best Practices and Analysis of Effectiveness and Sustainability

Abstract

Abstract This study highlights the water shut-off best practices and state-of-the-art technologies that are implemented in a wide range of wells. The study analyzes the best practices and decision basis for the most optimum water shut-off techniques that result in a successful and sustainable arrest of water production. Water management practices are an integral part of operations for mitigating premature water encroachment. Multiple techniques have been implemented by operating companies to shut off premature water entry zones using mechanical or chemical means; including mechanical and inflatable packers, retrievable and slim plugs, shifting sliding sleeve inflow control devices (ICDs), and chemical treatment to block undesired water-producing intervals. Historic water shut-off jobs were examined and the percentage of gain and water cut reduction for each well was calculated. This included the average sustainability time before wells revert back to their pre-water shut-off performance. On average, over 50 operations varying between vertical water shut-offs, horizontal water shut-offs, and sliding sleeve ICD shifting were analyzed. A post-isolation oil production increase of an average of 15% and water cut reduction by an average of 35% were observed. By analyzing the wells that underwent the water management activities, it was concluded that several factors played major roles in the success of water shut-off jobs and sustainability of well performance. Maintaining the effectiveness of water shut-off in the well was controlled by well configuration and trajectory, pre-water-shut-off production behavior, placement of the isolation barrier, well location and other key factors. This study acts as a valuable reference for future water management activities to ensure the success of the job and the longevity of producers.