Integrated Methodology for Production and Facilities Analysis to Optimize Barnett Shale Gas Production - A Case Study

Abstract

The Barnett shale is one of the most prolific gas reservoirs in United States and its success has continued into 2015, with the latest data showing that total gas production in the region is now about 5 Bcf/D. However, operators are increasingly aware that the productivity rate of Barnett wells shown to decline by an average of 70% in the first year. Additionally, as the result of the current down energy market it is necessary to implement new methodologies to sustain and optimize the production moving from the quantity of the wells to the quality of the production, from drilling more wells to enhance the production from the existing wells. To achieve this goal; it became crucial to choose the optimum artificial lift techniques and to use the right dose for chemical treatments that that work best in the Barnett to draw the well with minimum investment to maximize the cash flow.This paper illustrates the results of using an integrated methodology to evaluate and optimize the gas production for a brown field located in Dallas-Texas, USA. The methodology included a detailed field/wells production evaluation, optimization of the artificial lift system and design, review of the facilities configuration, identification of the flow challenges such as liquid loading, high line pressure and also down time management, Finally the study considered the economical evaluation for high lease operating expenses (LOE) wells. To make the work scalable and sustainable and to help engineers to be aware of any operational variance in timely manner two tools were implemented: 1) an artificial Lift screening methodology and 2) a surveillance tool for tracking the operational key performance indicator (KPIs) and containing an alarm system tool for spotting the variance.Out of 150 wells considered for this study, 94 wells have been identified for production optimization to obtain production enhancement. A set of seven wells has been taken as a pilot test covering two initiative; well cleaning and utilizing compressor to reduce the well head pressure. The results were as expected. Two wells under well cleaning show a 100 % increase in production because of the reduction in bottom hole pressure and achieving high draw down. The other five wells, under compressor initiative; show an average increase in production by 14 %. Additionally, the target is to reduce the number of the compressors by 25% using the proper artificial lift system and reduce the LOE by 10%.