Upload
others
View
2
Download
0
Embed Size (px)
Citation preview
Level measurement in a cement silo
•Continuousmonitoringtocontrolproductionandsecuresupply•Reliablemeasurementinextremelydustyatmospherewithproductfeaturingminimalreflectivity•Noflushingsystemsoralignmentmechanismsnecessary
1. Background Alargerecyclingcompanymanufacturescementasarawproductforuseinavarietyofitsownproductsaswellasforsaletoothercompanies.Thecementisstoredinalargesilowithaholdingcapacityofseveralthousandtons.Differentbatchsizesaretakenfromthereforfurtherprocessing.
2. Measurement requirements
Inordertocontrolproductionandensuresupply,thelevelofthecementinthesilo(morethan20mhigh)mustbecontinuouslymeasured.Theproductitselffeaturessomeinherentchallenges:cementispowderyandcompresseseasily,i.e.whenitisbeingremovedfromthebottomofthetank,theleveldoesnotdecreaseevenly.Instead,deeppitsformandlargechunkssticktothewalls.Cementhasverylowreflectivity(dielectricvalueapprox.1.8–1.9)andtheatmosphereinthesiloisextremelydusty.Therequestwasforcontactlesslevelmeasurementwhichhadpreviouslybeendoneusingultrasonic,butthismethodoftenfailedduetothegreatamountofdustintheatmosphereandthusneededtobereplaced.Thereisnocompressedairsupplyontheroofofthesilo.
APPLICATION NOTE Chemicals
Application 238 EN.indd 1 29.03.2010 13:12:03 Uhr
©KROHNE03/2010-238
-Su
bjecttoch
ange
with
outn
otice.
3. KROHNE solution
AnOPTIWAVE6300radarlevelmeterwasusedforcontinuous,non-contactmeasurement.Whenitcametotheantenna,apolypropylenedropantenna(specificallydesignedforsolidapplications)withanominalsizeofDN80wasused.Thedevicewasplaceddirectlyontheopeningofthesiloroof.
4. Customer benefi ts
Thissolutionallowstheoperatortomonitorthecementlevelatanytimeandthuseliminatesanydangerofputtingtheproductionprocessatrisk.
TheOPTIWAVE6300providesstable,reliablemeasurementdespitetheharshconditionsinthesilo.Theellipsoidalandcompletelyenclosedshapeoftheantennaaswellasitssmoothsurfacepreventdustdepositsontheantenna.Nospecialdustprotectionorflushingsystemisrequiredandtheantennafeaturesnomovingparts.Thiseliminatestheneedforregularmaintenance.
Thelowreflectivesurfaceoftheproductisreliablymeasuredthankstothehighsignaldynamicofthedevice.TheFMCWtechnologyisnotaffectedbytheangleofreposewhichmeansthattheantennadoesnothavetobelaboriouslyaligned.Thedevicecomespre-configured;atthetimeofon-sitestart-up,onlyafewparameterssuchassiloheight,blockdistanceandconeshapewereinputperdevice.
5. Product used
OPTIWAVE 6300 C • Radarlevelmeterforsolidapplications• 2-wireFMCW24...26GHzradar• Continuous,non-contactlevelmeasurement• Specificallydesignedformeasuringsolids•BasicversionwithDN80dropantennameasuresuptoaheightof30m• Pre-configuredexworks• Simplestart-upthankstotheinstallationwizardanditspromptingforthenecessaryparameters
• AlsoavailablewithDN150dropantennaformeasuringrangeupto80m
APPLICATION NOTE
Contact
PleasevisitourwebsiteforacurrentlistofallKROHNEcontactsandaddresses.
OPTIWAVE on the cement silo
Application 238 EN.indd 2 29.03.2010 13:12:05 Uhr