SAMPLESPECIFICATIONS
ELECTRODESTEAMBOILERMODELCEJS SPECIFICATION
ProvideHighVoltageElectrodeSteamBoilerforoperationon _KVPH,4wire,
HZ.Boilerratingshallbe PSIandshallbedesignedforoperationat
PSIsteam pressure, _MWcapacity.
1.0DesignTheboilerdesignshallconsistofapressure vesselhavingacentralcolumnfrom whichwater,underpressure, isforcedthroughnozzlestowardtheseveralelectrodes whichsurroundthecolumn.Steamisgenerated fromthesurfaceoftheseveral streams ofwaterbyheatgenerated astheelectricalcurrentflowsfrom theelectrode tothecentralcolumnandthroughthestream ofexcesswaterasitfallsfromthe electrodetoagrounded“counterelectrode”onitswaybacktothebottomofthe boiler.
Allstreams ofwateroriginatinginthecentralcolumnshallbeidenticalinshape based onpressuremaintained inthecentralcolumnthereforeavoidingsteam and interferencedroopcausingsplashingandpotentialelectricalshortleadingtoshut- down.
Thereshallbeanupperlevelman-way(s)allowingavisualinitialadjustmentof streamshape byvaryingthespeedoftheboilerpump(see2.1.4)toestablish suit- ablepressure inthecentralcolumnforinternaldistance based onvoltagespacing.
Regulationoftheboileroutputshallbeaccomplished byamovableloadregulating shieldwhichpreventspartorallofthenozzlestreams fromcomingintocontact withtheboilerelectrodes. Thepositionoftheloadregulatingshieldwillberegulated bytheboilercontrolstomaintainthedesiredsteampressureortopreventtheboiler fromdrawingmorethanthedesiredkilowattswhenthesteamrequirements exceed theboilercapacity.Theboilerelectrodesshallbelocatedentirelyintheboilersteam spacesothatstoppingoftheboilerpumpwillcause theboilertoshutdown.Regu- lationoftheboilercapacityshallbefrom100%to0%withoutthenecessityof interruptingthehighvoltagesupply.
2.0TheBoiler
ComponentParts
2.0.1 BoilerShell
Theboilershallbeasingleshell,verticaltype.Theshellshallbeconstructed and stamped inaccordance withtheASMEBoilerPressure VesselCode,andshall carryaNationalBoardPressure VesselRegistrationNameplate.
Theshelldesign(andstamped) pressure ratingshallbe PSIforoperationat PSI. Aman-way355mmx457mm(14"x18")shallbeprovidedforaccess totheboiler
interiorforinternalinspectionandrepair/replacementofinternalparts. Asecond
man-way
305mmx380mm(12"x16")shallbeprovidedattheupperlevelforinspectionof thejets.Nootheraccess isrequiredforinspectionorservice.Allboilerconnections over50mm (2")pipesizeshallbeflanged.
2.0.2 TheCentralColumnandNozzleStockPlates
Thecentralcolumnandnozzlestock,throughwhichwaterisconducted tothe streamnozzles,isfabricatedfrom mildsteelandsupported fromthetopofthe boiler.
Foroptimumwaterstreamshape, eachnozzlehasaconicalcollectorconeleading toaroundpipewithacrossinsertionformingstraightening vanes.Thisdesignpro- ducesasharplydefinedwaterstreamfromeachnozzle.
Thestreamnozzlesareinsertedintobolted,removableplatestoallowreplacement orcleaningwithoutremovalofthenozzlestockfromtheboiler.Nozzlerowsshallbe horizontallyslantedforsmoothprogressiveinterceptionandcapacitycontrol.
Thepumpshalldeliveritsfulloutputtothenozzlestockatalltimesandmaintaina constant staticheadinsidethenozzlestocktoassurethatatnotimeduringboiler operationwillanystreamnozzlehavelessthan15'ofliquidstaticheadsupply pressure.
2.0.3 ElectrodeBoxesandTargetPlates
Electrodeboxeshave3closedsidesterminatinginroundededges.
TargetPlatesareremovableandreversiblewithroundbarsfacingthejetstreams forsmoothcontact andnosplashing. Waterthenflowssmoothlyintheformed groovestoacollectionatthebottomofthebox.
Thebottomoftheboxissolidsteelwithmachined holeswithcrossinsertionto formthesteams ofwatertowardthecounterelectrode.
2.0.4 CounterElectrodes
Counterelectrodesshallbemadeofsolidsteelplatewithmachined holesmatching theholesinthebottomoftheelectrodeboxforsmoothflowinordertoavoid splashing. Solidweldedbracketforattaching toboilershell.
2.0.5 InsulatorsandPowerRods
Eachelectrodeboxissupported bythehighvoltagepowerrod.Powerrodsinsulat- ingtubesshallbequartz-25KVclass.
Insulatorsshallbe25KVclasshighgradealuminum, 9skirtsforlongtrackingpath, coated, formaximumprotectionandreliability.
Theinternalinsulatorshallbeprotected bystainless steelsteam throttlingshield andratedfor750PPMalkalinity.
Theexternalinsulatorshallbeidentical25KVclasscoatedinsulatorinordertooffer maximumprotectionagainstdepositsonskirtsduetoaircontaminantsinboiler roomatmosphere.
2.0.6 TheLoadRegulatingShield0-100%
Theloadregulatingshieldshallbeconcentricwiththecentralcolumnandwillbe supported byayokeandrodextendingthroughthetopoftheboilertotheloadreg- ulatingmechanisms.Theupperrimoftheloadregulatingshieldshallincorporatea stainless steel"knife"edgetointercepttheflowfromthewaternozzlesinamanner whichwillminimizethedisturbance tothenozzlestreams whichareabovethe shield.Thissharpedgeshallbeabletosplitthecapacityofastreamformaximum
accuracyincapacitycontrolandwithoutlossofqualityorexcessivesplashing. A shieldpositionIndicatorshallbeincludedinthecontrolsystem. Boilerwillbefur- nishedwithahydrauliccylinder,pumpandcontrolsystemtocontrolshieldposition accordingtodemand between0%and100%.
2.0.7 BoilerCirculatingPump(s)onseparateskid
Theboilercirculatingpump(s)shallbeacentrifugaltyperatedforcontinuous duty attheboileroperatingpressureandtemperatureandshallbeselectedforlowNPSH andtodelivertheflowandheadrequiredforproperoperationoftheboiler.The pumpshallbecoupledtotheboilerwithsuitablepipingspools,flangesandaman- uallysetbutterflyvalve.
Thepumpshallincorporateasinglemechanical sealwithwatercooling.Pump motorsshallbesizedformaximumpumphorsepowerrequirements andtobestan- dardshaft,T.E.F.C.,footmounted, andreadilyavailable.Thepumpwillbebelt- drivenorVSDdriven,allowingforasimpleinitialadjustmenttomaintainasteady pressureinthecentralcolumnandthereforeoftheshape oftheparallelwaterjets.
2.0.8 StandbyHeater
Theboilerwillbesuppliedwithanimmersiontypeflangedheatingelementassem- blyratedat V, Ph, Hzforuseinmaintainingtheboileratdesiredpres- surewhentheboilerisnotbeingusedtogeneratesteam. Thestandbyheatershall becontrolledbytwopressure setpointsandbythe"Standby-Run".
2.0.9 SteamWaterPreheater
Asteaminjectionpreheater hasbeenprovidedforquickerheatingofthe"cold"boiler waterafterashut-down. Itwillbringtheboilerto"stand-by"conditionbyusingan outsidesourceofsteam toheatthewaterandgeneratesteam intheisolatedboiler. Thisprocedureismanuallycontrolledbyahandvalve.
2.1BoilerControl
System
2.1.1 PressureandLoadControlsandassociatedControlPanel
Theboilercontrolsystemshallincorporateprocessorpressurecontrolandampere loadcontrolintheprimarycontrolsysteminamanner whichwillpermittheboiler tomaintain thedesiredsteam pressuresolongasthesteam demand doesnot exceedthedesiredmaximumKWlimitandatsuchtimesasthedemand exceeds therating,toregulatetheboileroutputtothedesiredmaximum.Themaximum allowableKWratingwillbeadjustable by theoperatortoratingsof100%maximum to5%minimum. Theboilerwillregulatetheoutputfrom0%to100%asrequired bythepressurecontrol.Boilerwillutilize"split"streams toattainstep-less control thatislinearoverentireoutputrangeoftheboiler.Stableregulationshallbepossi- blefrom100%outputdowntozeroload.
Controlsshallbeprovidedsoelectrodes areenergizedbeforewaterissuppliedto electrodes. Boilershallalwaysstartatzeroload.
2.1.2 Standby-RunControl
TheboilershallincorporateaStandby-Run controlwhich,whenin“Standby”,will manuallyoverridethePressure andLoadcontrolstocause theLoadRegulating
Shieldtogotothe“NoOutput”positionandsimultaneously energizetheStandby Heatercontrolcircuitandde-energizetheconductivitycontrolandsurfaceblow- down.WhentheStandby-RunControlisreturnedto“Run”,theboilerwillresume normaloperationstartingat“0”load.Thisoperationcanalsoberemotelycon- trolled.
2.1.3 LimitControls
Theboilershallbeequipped withlimitcontrolstoshutdowntheboilerineventof occurrenceofanyofthefollowingconditions:(1)excesspressure; (2)lowwater; (3)highwater;(4)sudden pressuredropinsystemsupplyline.Limitcontrols (optionalorsuppliedbyothers)suchassupervisoryrelaysforover-current,ground fault,orphase imbalance (suppliedbyothers)maybeconnected intothelimitcon- trolcircuit.
2.1.4 WaterLevelControls
Theboilerwaterlevelcontrolwillbeaproportionaltyperegulatorwhichwilladjust thepositionofavalveinthefeed-watersupplylinetomaintain theflowoffeed- watertomatchtherateofsteam generation. Ifasinglededicated suitablefeed- waterpumpisused,thecontrolvalve couldbereplacedbyavariablespeedcontrol onthefeedwaterpumpmotor.
2.1.5 ConductivityControl andSampleCoolerAssembly
Conductivityofthewaterbeingcirculatedtotheboilerelectrodeswillbecontrolled byanindicatingtypeconductivitycontrollerwhichwillhaveseparately adjustable highandlowsetpoints.Onactuationofthe“high”setpoint,automatic boilerbleed (surfaceblow-down)willbeginandalightwillindicatethatbleedisinprocess.
“Lowconductivity”closesaPLCcontactandmaybeusedtosignalachemicalfeed pumptostart.Chemicalfeedpumpisoptionalorsuppliedbyothers.Itisnotfur- nishedaspartofthisboiler.
ASampleCoolerassemblyshallbesupplied,includingthesamplecooler,connec- tionsfortheboilerwater,connections forthecoolingwater,valves,conductivity measuring cell,andmanual samplingvalve.
2.2BoilerTrimTheboilerwillbesuppliedwiththefollowingtrimitems:
2.2.1 PressureControlPiping
Pressure gaugeswillindicatesteam pressure intheboilershellandintheuser's steamheader. Gaugerangesshallbeapproximately2timestheoperatingpressure. TheGaugesandPressureControllerswillbemountedontheboilerateyelevel,pre- pipedandpre-wired.
2.2.2 Watergaugeglass
Watergaugeglasscompletewithdrainvalvewillbeprovided.
2.2.3 WaterColumn
Awatercolumnwillbeprovidedandwillbesuitableformountingofthewater gaugeglass,gaugecocks,thewaterlevelcontrollerandthehighandlowwatercut- offs.Awatercolumndrainvalvewillbeprovided.Aseparate controlisprovidedfor
the“Low-Low”waterlevelprotection.
2.2.4 Feed-waterValves
Boilerfeed-waterlinewillbeequipped withshutoffvalveandcheckvalvebetween theboilerandthefeed-waterregulatingvalveorpump
2.2.5 Blow-down Valves
Boilerblow-offlinewillbefittedwithonequickandoneslowopeningvalve.Valves shallbe“Y”patternratedforboilerblow-offservice.
2.2.6 SteamValve
Boilersteam outletvalves,suchasastopandcheck,areoptional.
2.2.7 BackPressureRegulatingValve
Apneumatic backpressureregulatingvalvewillbeprovidedandwillbeadjusted to throttleorclosewhentheboilersteam pressuredropsbelowtheoperatingpressure range.Valveandcontrollerwillbepneumatic type.ThisValvewillprotecttheboiler againstasuddendropinsystempressure. Timingshallbeadjustedforquickclosing andslowopening.
2.2.8 SafetyValves
TheboilerwillhaveaminimumoftwosafetyvalveswhichshallbeASMEratedand stamped.Aggregatecapacityofthesafetyvalvesattheirsetpressurewillnotbeless than110%oftheboilerratinginkilogramsofsteam perhour.Boilerratedoutput willbetakenas3.5lbs ofsteam perKW.(1.59kgofsteam perKW).
2.2.9 BleedValves (forconductivity control)
Theboilerbleed(surfaceblow-down)valveshallbeaneedletypevalvewithcali- bratedstem,optionaladderforboiler.Thisvalveshallbesettocontrolthebleed rate.On-Offcontrolofthebleedwillbebymeans ofaseparate valve,airoperated.
2.3Insulationand
Casing
Theboilerwillbeinsulated with2”ofglassfiberinsulationsecuredtotheboilerto preventsagging.Insulationringsareprovidedontheboilerpressure vessel.Insula- tioniscoveredby18GAAluminumsheets.
2.4TopCageTheboilerhighvoltageterminalswillbeenclosedinapreferablyfullheightheavy screenenclosurewithKirkkeyinterlockonaccess openingtoprevententrance unlesstheboilersupplyswitch-gearisopen.Kirkinterlockshallbesuppliedbyoth- ers.Switch-gearandKirkkeyinterlockprovidedbyothers
2.5ControlPanelPowerrequiredtoControlPanelis _V,3Ph, _Hz,incorporatinga A
disconnect switch.
Allelectricalcontrols,relays,pumpandshielddrivestarters andassociated push buttons, lights,ammeters,andothercomponents oftheboilercontrolsystemwillbe attachedto
theboilerbeforeshipment andpre-wiredwitha2doorNEMA12dustproofpanel.
PowerandControlsectionsareseparate,eachwithfrontaccess.
TheH.V.switch-gear(byothers)shouldincludeCTsandPTstobeconnected (by others)totheControlPanel.Inadditiontotheirusefortheboilercontrollogic,the informationonV,A,KWisavailableinthePLC.KWvaluecanbesenttoabuilding systemifdesired.
3.0BoilerAssembly andinstallation
Theboilerwillbeshippedintwocontainers oronaflatbedtruckinmainsections, andwillrequirefielderectionandassemblyandcompletionofelectricalandpiping connections. Theboilermanufacturer's representative willsupplylaborforthe assemblyandstart-up oftheboiler.Therepresentatives willreassembleunder supervisiontheinternalcomponents oftheboilerwhichweredisassembled(Power Rods,InsulatorsandBoxes) beforeshippinginordertoprotectthemintransit.Con- tainersshouldbeopenedatthesite.Thisisanopportunitytotrainlocalpersonnel. Boileraccess isthroughthelowerlevelmanhole.
Insulatedboilerisprovidedwithliftinglugsforhandlingverticallyorhorizontally. Labor,materialandequipment requiredforsettingoftheboilerandelectricaland pipingworkisnotincludedinthisproposal.
4.0ElectricalSupply
System
4.1HighVoltage
Switchgear
Theboilerwillrequirea3phase, 4wiresupplycircuitderivedfromadistributionor atransformerwithawye-connected secondaryandhavingthetransformerneutral groundedatthetransformerandextendedbymeansofafullsizeinsulatedconduc- tortotheboilerneutrallug.Theboilershellandcasingmustalsobegroundedto thebuildinggroundsystem. Themotorsspecifiedfortheboilercirculatingpump andshieldcontrolandstand-byheater willbe V,3Ph, Hz.,unlessoth- erwisespecified.Theboilercontrolcircuitswillbe120V,1phase, Hz.
Highvoltageswitchgearfortheboilersupplycircuitisnotincludedasapartofthe boilerproposal.TheboilersupplycircuitswitchgearshallbeairorvacuumorSF6 circuitbreakerratedfortheboilervoltageandampereloadandshouldbeequipped withprotectiverelaysasrequiredtoopentheswitchgearineventofphase unbal- anceorlossofaphase, over-currentandunder-voltage,andgroundcurrent.
Theswitchgearmayalsobesuchthatitcanbemadetoopenbytheboilerhigh pressurelimitcontrolforsafetyshutdown. Instrumentationshouldincludean ammeter andanammeter switchformonitoringofphase amperages.Thebreaker shallbeequipped withaKirkkeyinterlockwhichshallbekeyedtomatchthe access dooroftheboilerhighvoltageterminalcompartmentdescribedinpar.2.4.
ItwillbethePurchaser's responsibilitytoadvisethesupplieroftheswitchgearof theneedtocoordinatethekeyingsystemwithCleaver-Brooks.ProvideCT'sand PT'sforconnectiontoboilercontrolcircuitinboilerpanel(2.5). Theswitchgear shallincorporateadisconnectswitchorequivalentmeanstoprovideavisiblebreak inthepowersupplycircuittotheboiler.
5.0Feedwater
Treatment
Nofeed-watertreatment equipment isincludedinthisproposal.Thenecessary feed-watertreatment isnotdetailedinthistypicalspecification.
Thewaterhardness,requiredconductivityintheboilershell,waterpH,andalkalin-
ityplayakeyroleintheproperfunctioningoftheboiler.SeeElectrodeBoilers
RequiredWaterQualityParameterstable.
Boilerwilloperateatupto3500µmhoconductivityforreducedblow-downand
750PPMalkalinitywithsuperiorinsulators.