Integrating Operations Data and Hydraulic Models for Automated Choke Surveillance and Production Optimization

Abstract

Abstract Wellhead choke valve is a critical control element of a well that is used to regulate its drawdown, sand production and to execute optimal production-injection plan. Monitoring state of health of wellhead choke in a producing field is important to avoid production loss due to degraded and non-ideal choke valve performance and to proactively plan equipment maintenance. Automated wellhead choke surveillance tool was developed as part of in-house digital oil field application. The tool uses hydraulic models auto tuned to physical well tests to provide daily estimates of liquid and gas production rates in response to change in operations data; wellhead pressure and gas-lift rate. The predicted rates along with well specific choke valve sizing data are used as inputs to ELF valve sizing model to monitor current performance of wellhead choke valve. This approach determines the state of wellhead choke; whether it is plugged or eroded. Additionally, the tool predicts new trim size for replacement of eroded choke valves, and estimates uplift associated with replacement and maintenance of plugged and eroded choke valves. The surveillance tool has been used in conventional assets to identify plugged and eroded wellhead chokes. In one of the cases, it highlighted that excessive pressure drop that was potentially a result of a plugged choke. This was later confirmed by presence of excessive scaling observed in the flowline. In one more instance, the tool highlighted an undersized choke that led to calibration of wellhead sensor and helped in improving data integrity and quality. A wellhead choke monitoring tool that is integral part of internally developed digital oil field application is presented. The tool uses the updated hydraulic models with operations data to determine health of wellhead choke on daily basis. The tool is augmented with supporting visualization that tracks observed and expected choke performance over history and enables surveillance by exception by highlighting uplift potential associated with replacement and maintenance of wellhead chokes.