application 150 en 2 - krohne

Level Measurement of Biodiesel in a tank farm

•Highaccuracyandrepeatabilityforoptimisedtankfarminventory•One-stop-solutionforovera100tanks•Factorycalibrationforhighestmeasurementrequirements

1. BackgroundBiodieselandotherrenewableenergieshavebecomeanimportantissueworldwidewiththerisingpricesoffossilfuel.ArecentlybuiltEuropeantankfarmwithmorethan100stainlesssteeltanksprovidesastoragecapacityofover100000m3.Theplantuseswasteflowsfromvariousprocessesasrawmaterialsforotherprocesses–inordertoproducebiofuelandgreenpoweronalargescale.Itsbiodieselproductionispartiallybasedonwastecookingoilsandfatsfromthecateringindustry.

2. Measurement requirements

Theplantrunswithafullyautomatedtankinventorysystemandwaslookingforcost-effectiveandaccurateleveldevicescapableofmeasuringthelowreflectivemediumof108fueltankswithgreatrepeatability.Thedeviceshadtocomepre-calibratedtoreachanaccuracyof±2mm(on20m)withrepeatabilitybetterthan1mmandshouldnotbeaffectedbyvariationsindielectricconstant.

APPLICATION NOTE Energy

Application 150 EN 2.indd 1 21.03.2011 11:51:03 Uhr

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3. KROHNE solution

Forthisapplication,KROHNEdelivered108OPTIFLEX1300C2-wireguidedradar(TDR)levelmeters.Thesewereequippedwith4mmdiametersinglecableprobeswithalengthof20m.ConnectiontypewasG¾”AISO228.EachdevicereceivedspecificfactorycalibrationonKROHNEindustrialcalibrationrigstoreachthecustomerrequirementsintermsofaccuracyandrepeatability.

AlthoughtheTDR(TimeDomainReflectory)principlereliesonthedielectricconstantofthemedium,themetersarenotaffectedbyvariationsinproductcharacteristics:fittedonthetankroof,themetertransmitslow-intensityelectromagneticpulsesalongitscableprobe.Thesepulsesmoveatthespeedoflight.Whenthepulsesreachthesurfaceoftheproducttobemeasured,theyarereflectedwithanintensitythatdependsonthedielectricconstant(εr)oftheproduct.Thedevicemeasuresthetimebetweenemissionandreceptionofthepulse:halfofthistimeisequivalenttothedistancefromthereferencepointofthedevicetothesurfaceoftheproduct.Thetimevalueisconvertedintoacurrentoutputof4...20mAand/oradigitalsignalandtransmittedtothecontrolroomtotrackthefuelstockofeachtank.

4. Customer benefits

Inthisapplication,highmeasurementrequirementswerefullymetwitharobusttechnologyatacompetitiveprice.Byinstallingjustonedeviceoneachofthe108tanks,thecustomereasilymonitorsthebiodieselstockinthewholetankfarm.Withameasurementaccuracyof±0.01%andrepeatabilityhigherthan1mm,thestoredquantityisdeterminedclosetoafewhundredlitres.Eachdeviceisalsocapableofdetectingapossiblewaterinterfacebelowtheoillayer.Thisallowsforoptimisedfuelstockinventory.Inaddition,ourcustomersavesaconsiderableamountofmoneynotonlyinthebeginningbutalsointhelongrun:the2-wireOPTIFLEX1300CLevelMetersneedlesswiring,areeasytoinstallwithoutcommissioningandmaintenance-free.

5. Product used

OPTIFLEX 1300 C • Universallevelmeasurementdeviceforliquids,pastes,granulatesandpowders• Easyinstallation,commissioningandoperation• Maintenance-free• Specificfactorycalibrationforincreasedaccuracyandrepeatability• Suitableforflangetemperaturesupto300°Candpressuresupto300bar(processconditionscanevenbehigher)

• Measurementofinterfacesstartingat50mm

APPLICATION NOTE

Contact

KROHNES.A.S.LesOrs–BP9826103RomansCedexFranceTél.:+33475056703Fax:+33475050048level@krohne.com

PleasevisitourwebsiteforacurrentlistofallKROHNEcontactsandaddresses.

Application 150 EN 2.indd 2 21.03.2011 11:51:04 Uhr