SURVEILLANCE & OPTIMIZATION PROCESSES ASME/API GAS LIFT WORKSHOP ASME/API Gas Lift Workshop ExxonMobil Production Organization U. S. West Artificial Lift Team Gas Lift Operations Presented by Ignacio R. Gil - GL Coordinator Jesse Sendejo - GL Engineering Technician Houston, Texas February 5 & 6, 2002

EXXONMOBIL GAS LIFT OPERATIONS Five major gas lift areas (mature fields) Operate 500 gas lift wells (on land) Lift over 305,000 Bbls of fluid per day Artificial Lift Team Trained experts in our GL fields Quality surveillance/optimization tools and processes (best practices) Management support

Two ExxonMobil BHP trucks with Operators Assigned to Artificial Lift Team Utilize Electronic Memory Gauges Run Flowing and Static Pressure Surveys Run buildup tests Prepare reports and make recommendations to field and engineers BOTTOM HOLE PRESSURE OPERATIONS Tag bottom Run Temperature Surveys

BOTTOM HOLE PRESSURE OPERATORS

Surveillance Surveillance should be an ongoing process to identify efficient well performance and identify any changes in gas lift wells. Recommended Surveillance Processes: Monitor well tests and field production. Accurate well tests and maintenance of testing facilities is essential in identifying changes and early detection of problem gas lift wells. Each pumper should review morning report to identify any problems that need to be corrected or need further investigation. Monitor tubing/casing/GL line pressures. Any changes in these pressures need to be identified and evaluated. Monitor gas lift rates to wells and trend TGLR’s. Utilize well test seriatim sorted in descending order for pumping beat or field to help identify best and poor well producers. Identify bottleneck problems and minimize/remove flow line fluid chokes to improve gas lift well performance. Conduct periodic gas lift well reviews between operations and engineering to improve communications and discuss/identify problem wells. Utilize and request BHP data (FPT’s, SIBHP’s, TB, etc.) on any problem gas lifted well that has been identified. Communicate on problem wells to insure quick action.

Optimization Optimization should be an ongoing process to troubleshoot and fine tune all gas lift wells and ensure economic performance. Recommended Optimization Process: Install 2-pen pressure recorder to monitor the well during the unloading, troubleshooting and fine tuning process. Unload well slowly using a lower than normal gas lift rate to eliminate equipment failures. Unload well without a tubing fluid choke. If a tubing fluid choke is utilized to unload the well, monitor the well production and slowly work tubing fluid choke to open line as quickly as possible. Monitor tubing and casing pressures and start testing well production. Optimize well to maximize production (TBFD) USING THE LEAST AMOUNT OF GAS LIFT GAS POSSIBLE. Monitor production well tests to achieve this goal. Once gas lift well is optimized, schedule BHP operator to run a FPT (flowing pressure traverse) and a SIBHP (shut-in bottom hole pressure). Use data to: evaluate GLV design calculate PI determine operating depth as a basis for future design revisions to identify bottle necks

FLOWING PRESSURE TRAVERSE

NODAL ANALYSIS

FLOWING PRESSURE TRAVERSE