SURVEILLANCE & OPTIMIZATION PROCESSES ASME/API GAS LIFT WORKSHOP

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

2. 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

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

4. BOTTOM HOLE PRESSURE OPERATORS

6. 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.

7. 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

8. FLOWING PRESSURE TRAVERSE

9. NODAL ANALYSIS

11. FLOWING PRESSURE TRAVERSE

12. QUESTIONS???