Doubling Production From a Mature North Kuwait Reservoir

Abstract

This article, written by Senior Technology Editor Dennis Denney, contains highlights of paper IPTC 15334, ’Doubling the Production From a Mature Reservoir in North Kuwait - Challenges, Achievements, and Lessons Learned,’ by H.B. Chetri, SPE, M. Raju, SPE, Harry Alam, SPE, and Hussain Al-Ajmi, SPE, KOC, prepared for the 2011 International Petroleum Technology Conference, Bangkok, Thailand, 15-17 November. The paper has not been peer reviewed. [Note: Conference rescheduled to 7-9 February 2012.] Copyright 2011 International Petroleum Technology Conference. Reproduced by permission. Sabiriyah Lower Burgan (SA LB) is a clastic reservoir in northern Kuwait that has been on continuous production for 45 years. The reservoir, with an active waterdrive, suffers from a rapid increase in watercut. Production performance of the wells declines dramatically after the water cut reaches 40%. The formal strategy for production had been focused on keeping the active perforations away from water. In the past, the concern was to avoid installation of artificial lift or the application of water-shutoff or new technologies. Introduction The SA LB reservoir is a prolific reservoir with natural-aquifer support. The crude is light, at 33°API, and has less than 2.8% sulfur. Cumulative production is approximately 40% of reserves. The reservoir has produced only by natural flow at a daily rate for the last 3 to 4 years of approximately 50,000 BOPD, with average water cut of 29%. The team works daily to review and identify perforation intervals that could improve well performance. Also, the well reviews aim at identifying and implementing suitable water-shutoff jobs for improving the production performance. Therefore, close production monitoring, tracking of water movement, and use of surveillance techniques (e.g., production-logging tools) are key to the success of these production-management efforts. Geologically, water movement resulting from cumulative depletion has led to tortuous movement of the water front, which requires periodic mapping and integrating with production activities. Crossflow between layers, caused by inappropriate perforating procedures, also results in underperforming wells. To double production from the reservoir within 6 months, the following actions were taken. Extensive review of the well performance Intelligent analysis of existing wells Identification of production-enhancement opportunities (with reference to mapping resources needed), use of horizontal wells, and first-time installation of electrical submersible pumps (ESPs) More-ambitious ESP implementation than was contemplated earlier.