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Permanent real-time full wellbore flow monitoring using distributed fibre-optic sensingDavid Hill, CTO6th September 2015
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Agenda
• WhatisDistributedAcousticSensing(DAS)?• FlowmeasurementsusingDAS• Permanentflowmonitoring• Lessonlearned• Furtherdevelopments• Summary
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What is Distributed Acoustic Sensing?
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The Principles of DAS
• DistributedAcousticSensing(DAS)providescontinuousacousticmeasurementsalongtheentireopticalfibre:
Thefibreisthesensor
The Fibre Is The Sensor
Asingleopticalfibre canreplacehundredsorthousandsoftraditionalsingle-pointsensors
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Distributed Acoustic Sensing (DAS)How does it work
• CoherentOTDR– Coherentpulsepropagatesalong
thefibre– Tinydensity fluctuations frozeninto
fibreduringmanufacture→actasscattersites
– Scatteredlight iscapturedandtravelsbacktowarddetector
– Detectiontimedirectlymapstolocation
– Detectedintensityisafunctionofthelocalpropertiesofthewaveguide
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Distributed Acoustic Sensing (DAS)How does it work
• Coherentscatterpatternremainsconstantonsuccessivepings
• Vibrationfromanacousticsourcemodulatesthefiberandhencethescatterpattern
• Ahistoryofthenatureofacousticsourceasafunctionofpositionmaybedetermined
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Integrated Well Surveillance Using DASOne sensor … multiple applications … applied over the life of the well
ProductionCompletions
DAS
Evaluation
Vertical seismic Profile
Micro-seismic
Operation monitoring
FracProfiling
Cross Well Comms
Flow assurance
Permanent flow
monitoring
Smart well monitoring
Permanent flow
monitoring
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Flow ProfilingFlow Assurance
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• DASprovidesthecapabilitytocharacterizewellboredynamicsduringproductionthatwerepreviouslyestimated.
• Productionflowmonitoringcanbeacquiredovershortdurationsorthroughpermanentlydeployedon-demandsystems.
DAS Flow: Illuminating ProductionCharacterize Failed Startups and Wellbore Restrictions
Van der Horst, IPTC-17528-MS
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DAS for flow profiling workflow
PRE-PROCESSING• Frequencybandsdatageneration
• Timeaveraging• SNR
SPLITFLOWNOISE
• DepthMatching• Separateaxialandinflownoise
QUALITATIVEANALYSIS
• Eventsmonitoring
QUANTITATIVEANALYSIS
• Calibrationtosurfacemeasurements
• Inflowprofiling
POST-PROCESSING
• Visualizationandgraphics
1 2 3 4
DASDATA SURFACEFLOWRATE WELLSCHEMATICS TIMEZONE
5
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AsingleDASmeasurementcanconveydifferent information indifferent frequencies:
• Low frequencies:– Liquidtransport– Fluidinterfaces– Thermaldisturbances
• Medium frequencies:– FlowthroughICVs– Flowpastobstacles
• High frequencies: – FlowthroughGLVs
Information in Different Frequency Bands
in ‘t Panhuis, SPE-170917-MS
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• UsingDAS,gas-liftperformancecanbeanalyzedasafunctionofICVsettings,down-holeproduction &flowregime
HighFrequencies
LowFrequencies
Setting- ICVASetting- ICVD
DAS applications in Smart WellsGas-lift monitoring
in ‘t Panhuis, SPE-170917-MS
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DTS DASDAS - waterfall
DAS– waterfallAvgDiameterReduct.
• Presenceofwaxcanbepickedupascooling inDTSandalargepeakinDAS• EmpiricalDAScorrelationsmaybeusedtoquantifywaxbuild-up intimeanddepth
Wax Build-up MonitoringIdentification
in ‘t Panhuis, SPE-170917-MS
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Wax Build-up MonitoringMitigation• DASalsousedtomeasuretheeffectivenessof themitigationsolutionapplied
in ‘t Panhuis, SPE-170917-MS
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Wax Build-up MonitoringMitigation• DASalsousedtomeasuretheeffectivenessof themitigationsolutionapplied
in ‘t Panhuis, SPE-170917-MS
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DAS Flow: Operation MonitoringESP / PCP Condition Monitoring
Clearrpmswitching
Cavitation?
• SpectralanalysisoftheDASchanneladjacenttoanESPrevealsthetonalsproducedduringvariousratesofoperation.
• Frequenciescanberesolvedto~0.1Hz• Datacanbeusedforpredictivemaintenance
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Qualitative flow monitoringTime-lapse 3D visualization of flow
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4D Visualization of intelligent wells
SPE 170917 • Peter in ‘t panhuis
Visualization of flow across ICV’s and GLVs
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Flow ProfilingPermanent Flow Monitoring
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Production Optimization
Fluid Transport Optimization
Artificial Lift Optimization(if applicable)
1
2
3
Main goal:To increase production at lowest costs by:
Artistimpressionofawellfittedwithopticalsensingfibre andinflowcontrolsystems
3
2 1
DAS for permanent flow monitoringCost reduction and increased understanding• PermanentProductionLogging:
– Gas&LiquidratesperWell/Zone/Perf and2-phaseflow
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Permanent flow monitoring… for on-demand flow profiling
DAS IU
DAS PU
DTS IU
Solar panels Recording cabin
Separators
• Equipmentsetupatwellpad– Recordingcabincontainingequipment– RackcontainingbothDASandDTSequipment
Richards, SPE-173440-MS
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Permanent flow monitoringSystem architecture
• Webbasedlivequalitativeresults
• Dailyemailofperforationclusterefficiency
• Webbasedstatusmonitoring
• 24/7emailnotificationsofsystemfaults
• Remotecontrolandmaintenance
Richards, SPE-173440-MS
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Web accessible data… for on-demand flow profiling – QUALITATIVE MEASURE
• Historicalwaterfalldaterecordedandprocessed
Pero
ratio
ns
Days
Mon Tue Wed Thu Fri Sat Sun Mon Tue Wed Thu Fri Sat Sun
Days
• Flow/no-flowhistorydatageneratedateachperf cluster
Waterfalloftheacousticsignalsproduces attheperforations
Waterfalldatareducedto‘trafficlights’toindicateflow
Richards, SPE-173440-MS
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Web accessible data… for on-demand flow profiling – QUALITATIVE MEASURE
Longtermprofile– Exampleoffourweekperiod
Tue Wed Thu Fri Sat SunMon
Perforationclusterefficiency
• Permanentlyinstalledfibreandtopsideequipmentusedtoprovideon-demandflowprofile
64% @ 12:00 Thu
88% @ 20:00 Sat
• Duetothenaturalvariabilityinflowintermittentmeasurementscanproduceverydifferentresults
• RegularDASmeasurementsprovidesamoreaccuratelongtermtrend
Trend calculated from DAS measurements
Richards, SPE-173440-MS
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Lesson learned
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Lessons learned… from initial installations• Robustcommunications
– Allowingfordroppackets,failedresponse,periodofdowntime,etc
• Consistentrestorationofsystemparameterafterpowerloss
• ControlledshutdownusingUPS• ContinuousQCtoidentifyfailure
– Ofequipmentstatusandlivedata– Builtintest
• Movealgorithmstothecloud– Makesreprocessing(withrevisedparameter)easier
• Cloudbasedlogs– Fromobserversandmaintainers
• Maintainer‘alert’emailsneedtobeclearandnon-spamming
• Provideadministratorfacilitiestousers– Socustomerscanadd/deleteusers
• Needtokeepdataratesfromfieldtocloudlow
• RemotesetupoffieldPC
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Summary
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Summary
• DASisbeingusedtoprovidequalitativeandquantitativeflowinformation
• Downhole fibreandDASequipmentcanbepermanentlyinstalled
• Processedflowdataisuploadedtothecloudforondemandaccessviaanywebenableddevice
• Systemcontinuestobedeveloped• Providinguserswithdecisionreadydata
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Contact details
David Hill, PhDChief Technology OfficerQinetiQ Senior Fellow
OptaSense®
a QinetiQ company
Office: +44 1305 367126Mobile: +44 7909 890938Skype: David.Hill.OptaSenseWeb: www.OptaSense.com