Presentation on theme: "Gas-Lift Surveillance Techniques Jim Hall, Shell International EP Cleon Dunham, Oilfield Automation 20 – 30 Participants."— Presentation transcript:
Gas-Lift Surveillance Techniques Jim Hall, Shell International EP Cleon Dunham, Oilfield Automation 20 – 30 Participants
Gas-Lift Surveillance Techniques Objectives Deep Stable Optimum Data gathering / reporting Charge – 95% of data not used Objective -Collect key data once per minute -Have system check all data -If well is OK, nothing is reported -If well is sick (exception), it calls for help -People use data to troubleshoot problem wells What data is needed?
Gas-Lift Surveillance MeasurementsNeedWantUse Surface P inj YYGL analysis Q inj YYGL analysis/control P wh YYGL analysis Q liq YGL optimization T wh YDetect change in H 2 O P fl YGL analysis T ambient YT wh analysis Downhole P wf YGL optimization TYGL analysis Q inj YGL analysis/control Q singlephase YGL optimization T continuous YGL troubleshooting
Gas-Lift Surveillance Performance Indicators TGLRHydraulic effectiveness IGLREconomic effectiveness FGLRMust be calculated BS&WWhat is being lifted Others What if Downhole Instruments Fail Run flowing gradient survey Conduct accurate well test Calibrate multi-phase model Use calibrated model with measured surface data in between surveys and well tests
Gas-Lift Control Method Control MethodFrequency of Use Lift gas rate ManualCommon AutomaticFairly common Downhole 1 Very new Injection pressure Manual - AutomaticRarely Downhole 1 Very new Production pressure ManualFairly common AutomaticVery specialized 1 If using downhole control, need automatic fallback to surface method