krohne - leak detection and localisation

PiPePatrol

Leak Detection and Localisation

Zero false alarms by Leak Pattern RecognitionUltra-fast leak detectionEasy retrofit using existing field instrumentationInterfaces to existing SCADA system

uNofalsealarms

BR_PipePatrol_2009WorldGas.indd 1 17.09.2009 12:34:15

2 LeakDetection&LocalizationPipePatrol

Nowisthetimetoconsideragoodandreliableleakdetectionsystem...

Imaginehowa1%leakina20linecantranslateinto450,000barrelsperyearorcouldcontaminate10squarekilometresoflakewithin24hoursifleftunde-tected.KROHNEsPipePatrolallowsyoutoreactquicklyandreliablyto:

Therearemanyleakdetectionpossibilities,buthowmanyarereallyaviableproposition?

Agoodandreliableleakdetectionsystemshould:

ExternaldamageTheftCorrosionleaksContaminationExplosions

LegislationSafetyissuesEnvironmentalissues

Detectsmallleaks......veryquicklyNotgivefalsealarms!LocatetheleakpreciselyBeoperatorfriendlyRequirenomaintenance

RemainsensitiveevenundertransientconditionsPermanentlybeavailable24/7

Spontaneousleakstypicallyoccurduringstart-up,shut-downandoperationalchanges.Thisislogical,sinceundertheseconditionsthepressureinthepipe-linechanges.Unfortunately, thechangingpressurecauses transients; inletandoutletflowwillvarydrastically.Agoodleakdetectionsystemshouldbeabletocopewiththesetransientsreliablyandretainitsabilitytodetectsmallleaksveryquickly.


3HowdoIchoosetherightsystemformysituation?

LeakDetection&LocalizationPipePatrol

PipePatrol

-TheKROHNELeakDetectionSystem

DevelopedinconjunctionwithleadingexpertsfromoneofGermanys technical universities, PipePatrol was initiallydesignedforthemostdemandingpipelinesintheGerman(petro)chemical industry. After extensive testing they re-leaseditfortheOil&Gasindustry.ContinuousdevelopmentovertheyearshasledtothesuiteofsystemsthatKROHNEmarketsunderthenamePipePatrol.

PipePatrol can use existing instrumentation,meaning in-stallationisnotanissue.

KROHNEsPipePatrolhasbeensuccessfully implementedongasand liquidpipelines throughout theworld, therebyeasily fulfillingregulationssuchas theGermanTRFLandrecommendationssuchastheAmericanAPI1130andAPI1155.

Rapid,reliable/rightalltimesAgoodleakdetectionsystem,suchasPipePatrol,willgiveyouaneasy tounderstandoperator interface,willgiveanunmistakablealarm,andmoreover,beingrightalltimes,itwontsendyououtinthemiddleofastormchasingaphan-tomleak.

Itwillinterfaceseamlesslywithyourexistingsystems,plac-ingveryfewdemandsonyourinstrumentationnoronyourpersonnel. The operator only seeswhat he needs to see;trainingisthereforelimitedtoafewhours.

NoFalseAlarms


4E-RTTMstandsfor

ExtendedRealTimeTransientModelling.

E-RTTMistheonlyproventechnologythatcompareswhat ishappeningwithwhatshouldbehappeningin the pipeline to give a consistently sensitiveassessmentofpipelineintegrity.

Unlikeothersystemsitdoesnotsimplycomparetheoutletflowwiththeinletflow.Itusesthepressureandtemperatureatinletandoutlettocalculatetheflow.Thiscalculatedflowissubsequentlycomparedtothemeasuredflowforbothinletandoutlet.TheE-RTTMmodelinstantaneouslyanalyzesthisdatatodeterminethestatuswithinthepipeline.

Because E-RTTM uses relative values, it is notaffectedbyandcanworkefficientlyundertransientconditions without any notable effect on itssensitivity.

ExtendingRTTMbyaLeakPatternRecognitionhascreatedahighlysensitive,reliableandfalse-alarm-freeleakdetectionsystem.

.

WhatarethebenefitsofE-RTTM?


Measuredinletandoutletflowdeviateconsiderably...

Whentheresidualchanges,PipePatrolanalysestheshift:Isthissimplysensordrift,...oratrueleak?

Thedifferencebetweenthecalculatedflowandthemeasuredflowisthere-sidual(andisessentiallyzeroforaleakfreepipe).

E-RTTMisprobablytheonlytechnologythatallowsfastandsensitiveleakdetectionintransientlyoperatedpipelines


5Pressureatinletandoutlet*

Temperatureatinletandoutlet*

Flowatinletandoutlet*

Ambienttemperature*

*Thesecanbetakenfromexistinginstrumentation.

Beforecommissioning,PipePatrolrecordsthepipelinedataunderworkingconditions.UsingthisdataallowsPipePatrolto reach maximum sensitivity without knowing the exactpipelineproperties.

Throughoutitsoperationallife,PipePatrolrecordsalldatawhichmeans that thecriticalparameterscanbe tuned tocontinuouslyguaranteemaximumperformance.

E-RTTMusesexistinginstrumentation...

WemeasureinbucketsnotbarrelsThere is a 10 inch pipeline inNorthernGer-many-stretchingoveradistanceof31km.AseriesoftestsweredoneonaninstalledPipe-Patrol System at flow rates between 210 and265m3/hwhilecreatingaleakinthepipelineat22.4kmfromtheinlet.

Inonly30seconds,PipePatrolwascapableofdetecting a leak of only 0.5% of the nominalflow.Thismeansonly35 litres leakedoutbe-foretheleakwasdetected.

35litresareonly3bucketfuls.

NofalsealarmsApartfromtheoutstandingandhighlywelcomeperformance, PipePatrol features unique leakpatternrecognition.Thisleakpatternrecogni-tion comes from theunderlying technology ofExtended Real-Time Transient Modelling (E-RTTM).

ThebasicRTTMgoesmuchfurtherthansimplecompensatedmassbalance.Ittakestransientsintoconsideration.Transientsareomnipresentinanypipelineasaresultofdrawingoffprod-uct,filling,packing,productchanges,rampingupandrampingdown.

RTTMmeasuresthepressureandtemperatureattheinletandoutlet,andcalculatestheflowfromthis.Itthencomparesthecalculatedflowwiththeactualflowmeasuredby(alreadyexist-ing)flowmeters(anyflowmeterpresentcanbeused).Theresultisacomparisonofmeasuredversus calculatedflowat inlet and outlet (notsimply at the outlet like traditional systems),whichaloneprovidesmuchbetterresults.


6NofalsealarmsPipelineLeakDetectionandLocalizationforLiquidandGasPipelines.


Welltellyouwheretheleakis.Ontheaforementioned10inchpipelineinNorthernGermany,PipePatrolnotonly

detectedtheleakbutalsolocalisedit.

TheleakwascreatedbyreleasingNaphthafromthepipelineintoatankertruck

thatwaspositionedat22.4kmalongthe31kmlongpipeline.

Thefigureshows:

BlueLine:

Theinletresidual(differencebetweencalculatedandmeasuredflowatinlet)

Greenline:

Theoutletresidualsduring(differencebetweencalculatedandmeasuredflowat

outlet)

Twophenomenacanbeseenfromtheseresiduals:

1.Theoutletresidualstartstodeviatefromzerobeforetheinletresidualdoes.

Thiseffectoccursbecausetheleakwascreatedclosertooutletandthenega-

tivepressurewavethereforearrivesatoutletearlierthenitdoesatinlet.In

otherwords,thisistheWavePropagationMethod!

2.Theoutletresidualdeviatesmorethantheinletresidual.Again,thisiscaused

becausetheleakwasclosertooutletandthepressuregradientatoutlet

behavesdifferentlyfromthepressuregradientatinlet;heretheGradientInter-

sectionMethodisseen.

OfcoursePipePatroldoesnotaskanoperatortointerpretthesegraphs,but

showsanarrowonamap,indicatingtheleaklocation.Onthis10inch,31kmlong

pipelinethethiswasdonewithanaverageaccuracyof0.5%.


7Whereistheleak?-Exactly.

WavePropagationMethod

-usingtimeofflightAspontaneous leakwillcauseanegativepressurewave in thepipeline,simplybecausegasorliquidisleakingout.Thispres-surewavewilltravelthroughthepipelineatthevelocityofsoundofthegasortheliquidinthepipeline.Dependingonthelocationoftheleakthepressurewavewillarriveatoneendbeforeitar-rivesattheother.Theleakpositioncanbecalculatedfromthedifferenceinthearrivaltimesatinletandoutlet.

GradientIntersectionMethod

-usinginterpolationUnderzeroleakconditions,thepressuredropisevenlydistrib-utedalongthepipeline.

Whenaleakoccurs,thepressuredropinthesectionbeforetheleakishigherthanthepressuredropinthesectionaftertheleak.Thisislogical,sincegasorliquidisleakingout;moregasisbe-ing transported through thepipelinebefore the leak thanafterthe leak.The leak location is foundat thepointwhere the twogradientsintersect.


Wavepropagation

Gradientintersection

Functions PipePatrolisasystemforleakdetectionandlocalizationthatalsofunctionsduringpumpingandramp-upandramp-downconditions,andprovidespermanentmonitoringduringstationaryandtransientconditions.Supportingfunctionsincludebatchtrackingandinstrumenterroranalysis.Providesstand-aloneoperationwithouthumaninteraction

StandardsandRegulations FulfilsAmericanAPI1130(ComputationalPipelineMonitoringforLiquidPipelines)andGermanTRFL(TechnicalRulesforPipelines),aswellasnumerouslocalstandardsincountriessuchasRussia,Canada,Brazil,Malaysia

AreasofApplication Liquidandgaspipelinesfromsimplesinglelinesuptocomplexnets(whereinstrumentationisappro-priate).Liquidapplicationscoversinglebatchandmulti-batchoperationwithorwithoutDRA

On-siteinstrumentation PipePatrolusesexistingstandardflow,pressureandtemperatureinstrumentationatinletandoutlet.Substationinstrumentationimprovesperformance.

Connectivity InterfacestoanySCADAsystem.StandardinterfacesincludeModbus/Modbus+andOPC

Specifications


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KROHNEOil&Gas

Minervum74414817ZGBredaTheNetherlands

Tel.:+31-76.711.2000Fax.:+31-76.711.2001

[email protected] www.krohne-oilandgas.com

SystemsFlowMetersforCustodyTransfer

LiquidFlowMeteringsystems

GasFlowMeteringsystems

WetGasMeteringSystems

Provers&MasterMeters

FlowComputing,SupervisorySoftware&AnalyserManagement

CalibrationSystems

TankInventory&ManagementSystems

AnalyserHousesandShelters

Loading&Offloadingsystems

LeakDetectionandLocalisationSystems

Revamps&Upgrades

Testing,Installation,Commissioning,Service

Training

KROHNEOil&GasOverview

Fromthewellhead,throughpipelines, onto tankersandintotheterminalsandrefineries; the flow of oiland gas products needstobemeasuredaccuratelyandreliably.

ThatistheworldofKROHNEOil&Gas.

ThescopeofKROHNEOilandGasstartswithcustodytransfer flow metering for oil, gas and liquefied gasandcontinuesthroughtankmanagement,loadingandoffloadingandleakdetectionandlocalisationsystems.

KROHNE Oil & Gas is part of the KROHNE Group.KROHNEOil&GassheadquartersarelocatedinBreda,theNetherlands,close toEuropesmajorOilandGascentres.

Wehave growndynamically and nowhave one of theindustryslargestteamsofengineerssolelydedicatedtooilandgas.

KROHNEOil&GashasmanufacturingfacilitiesintheNetherlands, UK, Malaysia, USA, Brazil, Colombia,Middle East. The headquarters in Breda servicesthe worlds oil industry through its own offices andthroughtheKROHNEgroup,inmorethan60countriesworldwide.

The parent company, KROHNE, has 42 ownedsubsidiaries and representatives for every country intheworld.Wemakeuseofthisnetworktomaintainahighlevelofserviceforourcustomers.

KROHNEOil&Gasprovidespecialisedknowledgefirst-handwiththebackingoftheworldsmostknowledgeableconcerninthefieldofflowmeasurementtechnology.

ProductsGasUltrasonicFlowMetersforCustodyTransfer

LiquidUltrasonicFlowMetersforCustodyTransfer

MassFlowMetersforCustodyTransfer

VenturisforWetGasMetering

FlowComputers

SupervisorySystems

MeterValidationSoftwarePackages

ElectromagneticFlowmeters

LevelMeasuringInstruments

VariableAreaFlowmeters

TemperatureMeasuringInstruments

PressureMeasuringInstruments

Analyzers

VortexFlowmeters

FlowControllers


krohne - leak detection and localisation

Documents

pipepatrol leak detection

existing instrumentation

localisationzero false

relative values

extensive testing