What is the cooperation between other processes and flue gas desulfurization and denitrification?
Althoughithasenteredthe21stcentury,China'senergystructureisstilldominatedbyfossilenergy.Coalandoilarestillintheforefrontforalongtime.Coalaccountsforabout70%ofChina'stotalprimaryenergyconsumption.ThepollutionofSO2andnitrogenoxidescausedbycoalisthemainsourceofpollutionintheurbanatmosphereofChina.Atpresent,thecontrolofvariouspollutantsisgenerallycarriedoutbyseparateremovalmethods.Thesulfuricacidequipmentwillcausethecomplexityofthefluegaspurificationsystemandtheimprovementofthetreatmentcost,andbecausethesystemistoocomplicated,thecooperationbetweenthemwillbemoredifficult.Thisresultsinareductioninreliability. Solidphaseabsorption/regenerationfluegasdesulfurizationanddenitrationtechnologyThesolidphaseabsorption/regenerationfluegasdesulfurizationanddenitrationprocessusesasolidabsorbentoracatalysttoabsorborreactwithSO2andnitrogenoxidesinthefluegas,andthentheSO2andnitrogenoxidesarereleasedfromtheabsorbentintheregenerator.Theabsorbentcanberecycledbacktotheabsorberforrecycling;therecoveredSO2canbefurtherprocessedtoobtainby-productssuchaselementalsulfuroracid;thenitrogenoxidesaredecomposedintonitrogenandwaterbysprayingammoniaorrecyclingtotheboiler.Theabsorbentscommonlyusedintheprocessareactivatedcarbon,copperoxide,molecularsieves,silicagel,etc.Thebedoftheabsorptionequipmentusedhasafixedbedandamovingbed,andtheabsorptionprocessvariesdependingonthemannerandpurposeoftheabsorbentregeneration.Gas/solidcatalyticsimultaneousfluegasdesulfurizationanddenitrationtechnologyThistypeofprocessusesacatalysttoreducetheactivationenergyofthereactionandpromotetheremovalofSO2andnitrogenoxides.Theremovalefficiencydependsonthecombinationofthecatalyticreactionandthecatalyst;andithashighernitrogenoxideremovalefficiencythantheconventionalSCRprocess..Elementalsulfurisrecoveredasaby-productandnowastewaterisproduced.Absorbentinjectionandfluegasdesulfurizationanddenitrationtechnology Drypowdersuchasalkaliorureaissprayedintoafurnace,flueorspraydryscrubbertosimultaneouslyremoveSO2andnitrogenoxidesundercertainconditions.Theseprocessescansignificantlyremovenitrogenoxides,andthedenitrationratemainlydependsontheratioofSO2andnitrogenoxidesinthefluegas,thereactiontemperature,theparticlesizeoftheabsorbent,andtheresidencetime.AnimportantfeatureofthisprocessisthepresenceofatemperaturewindowinwhichtheadditionofanalkalinechemistryallowssimultaneousremovalofSO2andnitrogenoxides.
What is the function of each part of the conventional electric defogger?
Theelectricmisteliminatorhashighdustremovalefficiencyandlowemissionrate.Eachpartofthewetelectricityhasuniquefunctions: 1.Shell:Generally,itisacorrosion-resistantmaterialsuchassteel-linedglassflakes.Dividedintoverticalstructureandhorizontalstructure.Theshapeofthehousingisdividedintoacircleandasquare.Accordingtotheactualsituation,itcanbesetintheupperpartofthedesulfurizationtower,oritcanbesetseparately.2,intakemode:accordingtotheactualsituationcanhavedifferentsettings.Verticalstructure:lowerintakeair,upperairoutlet;upperairintake,lowerairoutlet.Horizontalstructure:flatintoandout.3,dustcollectinganodeplate:thechoiceofcorrosion-resistantmaterials,variousmaterialshavetheirownadvantagesanddisadvantages,accordingtotheactualcompositionofthemediumcompositionandtemperature.Desulfurizationfluegashasalargeamountoftreatmentgas,andtheanodeisgenerallyaplatetypeandahoneycombtype;theotherusesmostlyaroundtubetypeandahoneycombtype.4,dischargecathode:avarietyofmaterialsandmodelsareavailable.Corrosion-resistantmaterialsareselectedaccordingtogasconditions,mainlyinthefollowingtypes:stainlesssteel,lead-bismuthalloy,andtitaniumalloy.5.Insulationdevice:Themainheatingmethodiselectricheatingandhotairheating.Preventtheinsulationquartztubeinsidetheinsulationboxfromdewclimbing.6.Flushingsystem:intermittentflushingorcontinuousflushing. 7,inacorrosivegasenvironment,theshellandinternalcomponentsmustbemadeofanti-corrosionmaterialsandanti-corrosiontreatment.Theelectricmisteliminatorisgenerallyusedforsmeltingfluegassulphuricacid,titaniumcalciningtailgastreatment,chemicalplantvariousacidmisttreatment,andisthegas-liquidseparationwetmethodwiththeleastresistancetopurifyingfluid.Theelectricdefoggerhasvarioustypessuchasvertical,horizontal,multi-tubeandwireplate.Electricmisteliminatorsaremostlyusedinindustriessuchassulfuricacid.ThroughthestaticcontroldeviceandtheDChighvoltagegeneratingdevice,thealternatingcurrentisconvertedintodirectcurrentandsenttothedemistingdevice,andalargeelectricfieldisformedbetweenthecoronawire(cathode)andtheacidmistcollectingplate(anode),sothattheairmoleculesareIonizationgeneratesalargeamountofelectronsandpositiveandnegativeionsinaninstant.Theseelectronsandionsmoveinanorientateddirectionundertheactionofanelectricfieldforce,formingamediumfortrappingacidmist.
Do you know what the conventional electric defogger works?
Theelectricdefoggerhasvarioustypessuchasvertical,horizontal,multi-tubeandwireplate. Whentheelectricdefoggerworks,itgeneratesanunevenelectricfieldbetweentheyinandyang.Therefore,bothpolesneedtobeelectricallyconductive.Generally,anelectrostaticmisteliminatorofnon-metallicmaterialssuchasFRPorpolyvinylchlorideadoptsamethodofconductingelectricitybymeansofaliquidfilm;aconductiveglassreinforcedplasticobtainedbymixingandcompressingFRPandgraphite,oramethodofaddingacarbonfibermattoaninnerlayerofaFRPanode;Tosolvetheconductiveproblem.Theelectricdemisteranodetubeplateisnowmainlymadeofplastic,leadandconductiveglasssteel.Sincetheplasticelectricdefoggeriselectricallyconductivebytheliquidfilm,theeffectiveprecipitationareachangesgreatly,andtheoperatingvoltageandcurrentarelow,theeffectisnotasgoodasthelattertwo;inrecentyears,theleadanodetubesheetiscontinuouslyreplacedbytheconductiveglassreinforcedplastic,Lightweight,lowprice,outstandingcomprehensiveperformanceandsoon.ConductiveFRPelectricmisteliminatorsmainlyhaveindicatorssuchastreatmentgasvolume,totalpressuredropandoutletacidmist.Theworkingprincipleoftheelectricdefogger:throughthestaticcontroldeviceandtheDChighvoltagegeneratingdevice,thealternatingcurrentisconvertedintodirectcurrentandsenttothedemistingdevice,formingastrongbetweenthecoronawire(cathode)andtheacidmisttrapplate(anode).Theelectricfieldcausestheairmoleculestobeionized,andinstantaneouslygeneratesalargeamountofelectronsandpositiveandnegativeions.Theseelectronsandionsmoveinanorientateddirectionundertheactionofanelectricfieldforce,formingamediumfortrappingacidmist.Atthesametime,theacidmistparticlesarecharged,andthechargedacidmistparticlesareorientatedbytheelectricfieldforceandreachtheanodeplateforcollectingtheacidmist.Afterthat,thechargedparticlesreleaseelectronsontheplates,sothattheacidmistiscollectedandflowsundergravitytotheacidstoragetankoftheacidmistremover,therebyachievingthepurposeofpurifyingtheacidmist. Sincetheelectricmisteliminatorisgenerallyinanacidicatmosphere,itmustbemadeofamaterialhavingagoodcorrosionresistance.Commonlyusedmaterialsarelead,hardPVCandfiberglass.Amongthem,leadelectrostaticdemisterapplicationshavethelongesthistory.Therearealsomanykindsofmaterialsforthecathodecoronawireofthemisteliminator,suchasnickel-chromiumsteelwireoutsourcinglead,titaniumpalladiumalloywire,titaniumwireandthelike.
How does a wet electric mist eliminator work in general?
Manycompaniesevenknowalotofwetelectricmisteliminators,butitisnotveryclearhowthewetelectricdefoggerworksandwhatworks.ShandongLinyiZhengxinElectricdefoggerengineersanalyzethewetelectricdefoggerwork.principle: Whensuchawetgaswithsuspendedparticlesenterstheelectricfieldoftheelectricfilter,sinceasufficientlyhighDCvoltageisappliedtothecoronapolelineoftheelectricfilter,alargeamountofelectronsmovingtowardthesedimentatahighspeedareemittedfromthecoronapole.Undertheactionofelectricfieldforce,high-speedmovingelectronscollidewithneutralmoleculesathighspeed,andoneorseveralouterelectronsareemittedfromgasmolecules.Neutralmoleculesareconvertedintopositiveionsandfreeelectrons.Thesederivedelectronscontinueundertheactionofelectricfield.High-speedmovement,impactingnewneutralmoleculestoionize,andthusrapidlyderivingnewionsandelectrons,avalancheionizationofgasnearthecoronapoleline,forminganionizationzone2mmaroundtheelectrodeline.Atthesametime,thenegativelychargedparticlesandelectronsaretrappedbythemistparticlesinthetransitionzoneduringthemovementofthesedimentarypole.Theneutralparticlesarechargedandgrown,continuetomovetowardthesedimentarypole,andfinallydepositandelectricallyneutralizeatthesedimentarypole.Agascontainingfinesuspendedseeds,inatubularwetelectricfilter,theymoveinthedirectionoftheaxisofthetube,whereinthesuspendedparticlesaredrivenbytheflowofthegas,thegravityoftheparticlesthemselves,theelectricpoweroftheelectricfield,thefrictionofthemovementoftheparticlesThecombinedeffectofforceandelectricfieldforce.Themovementofchargedparticlesintheelectricfieldiscarriedoutunderthecombinedforceoftheaboveseveralmainforces.Therefore,itsmovingspeediscalledthedriftvelocity.Foranyparticularwettypeelectricfilter,whenthedriftspeedistoosmall,ifthegasisionized,thetimerequiredfortheparticlestochargeandtheparticlestopassbetweenthetwopolesislongerthanthetimerequiredforthegastopassthroughtheentirelengthofthetube.Thesuspendedparticlesareescaped.Theelectricfieldproduces"coronaocclusion".Therefore,themagnitudeofthedriftvelocitydeterminestheelectricfieldgasvelocityoftheelectrofilterandtheefficiencyofdefogging.Thetheoreticalvalueofthedriftvelocityiscalculatedasfollows:w=0.11E2ρ/μcm/sec (1)where:w—driftvelocity,cm/secE—electricfieldstrength,volts/cmρ-particleradiuscmW—driftvelocitycm/secμ-gasviscosityg/cm.Seconds(Pois)Asseenfromtheaboveequation,thedriftvelocityofaparticleisproportionaltothesquareoftheelectricfieldstrength,theradiusoftheparticle,andinverselyproportionaltotheviscosityofthegas.Theelectricfieldstrengthofanysinglepositionintheelectricfieldiscalculatedasfollows:Ex=U/[2.3xlg(R/r)]volts/cm(2)where:E-fieldstrengthatanypositionintheelectricfield,volt/cmU-voltageappliedtothecoronaelectrode,voltx-distancefromthecoronaelectrode,centimeterlg-basedon10Logarithm,R—radiusoftheprecipitationpole,centimeterr—radiusofthecoronaelectrode,centimeterAwetelectricmisteliminatorthatcontainsasubstanceofsteam.Whencooledtoacertaintemperature,thesteamcondensesintoaliquidorasolid,andthewetelectricdefoggercleansthefineliquidandsolidparticlessuspendedinthegas.Thewettypeisthattherearesufficientliquidparticlesinthemediumpassingthroughtheelectricfieldandthemediumgasissaturatedbytheliquidvapor.Thewetelectricmisteliminatoristomeettheproductionprocess,environmentalprotection,valuablemetalrecovery,removethesuspendedmatterinthegas,anddischargethegasafterpassingthetreatment.
Why is a wet electrostatic precipitator defogger a good choice?
Do you know what to pay attention to when operating lead defogger equipment?
(1)PowersupplyequipmentInorderfortheleaddefoggertooperateefficiently,itisdesirabletoalwaysapplyashighavoltageaspossible.Therefore,specialattentionshouldbepaidtotheinsulationoftheconductiveportionandtheearth,theconstructionofthesupport,andthematerials.Ifmoistureordustadherestothesurfaceoftheinsulatingporcelainbottleorismixedintotheinsulatingoiloftheelectricmisteliminator,theelectricalinsulationwillbesignificantlydeteriorated,andtheeffectivevoltagewillbelowered.Theinsulatedporcelainbottlethathasbeenthoroughlycleanedismeasuredtobeinfinitelylargewitha1000Vmegohmmeter,andatleast20Mnshouldbeusedasareference.Insulatingporcelainbottlesshouldberegularlycleanedaccordingtotheconditionsofuseandenvironment.Inaddition,theinsulatedporcelainbottleshouldbeplacedintheboxandhotairshouldbesenttoavoidtheinfluenceofwetgasanddust. Inthecaseofthyristorrectification,temperaturehasaneffectonitsoperatingcharacteristicsandlife,soitisnecessarytopayattentiontothetemperaturerisearoundthethyristor.Thethyristorrectifierisstoredinthesump,andsinceitisoftencooledbyinsulatingoilorthelike,thereisnoproblemoftemperaturerise,butattentionshouldbepaidtocontaminationbyamoistureabsorbingrespiratororthelike.Ifthemoistureabsorbingrespiratoriscontaminated,moisture,etc.enterstheinsulatingoilofthesump,whichoftencausesinsulationdeterioration.(2)ExcretionofacidmistFortheleadelectricmisteliminator,theacidmisttrappedisgraduallydischargedasadischargeliquidfromthelowerpartoftheroomtotheoutside.Sincethemetalcompoundorthelikeinthedischargeliquidmayblockthedischargepipe,causingacidaccumulationintheintakechambertocauseanincreaseingasresistance,careneedstobetaken.(3)DustcollectionroomInthedustremovaldevice,thegastemperaturewillcausechemicalcorrosionbelowthedewpoint.IftheH20-H2SO4condensationcausesleakageonthesurfaceoftheinsulator,oradheresdustontheelectrodeline,orformsaninsulatingcoatingfilm,thegastemperatureshouldbekeptatalltimes.Abovethedewpoint.Ontheotherhand,attentionshouldalsobepaidtofailuresduetothermalstressofthememberatahightemperatureof500°Corhigher.Ingeneral,itisdesirabletooperateatatemperatureofabout50°ChigherthanthedewpointofthemixedgascontainingS02andSO3.Fortheelectricdefogger,inordertopreventtheefficiencyfromdecreasing,itisdesirabletooperateatatemperatureof40°Corlower.(4)CleaningofthedefoggingchamberAfterthelong-termoperationofthedemistingchamber,thedustremovalefficiencyisgraduallyreduced.Therefore,cleaningmustbeturnedonatanappropriatetime.Theperiodiccleaningcycleisdeterminedbythetypeofmine,thetypeofroaster,andtheoperatingconditions.(5)InsulatingoilforoilsealWhenthelead-typeelectricmisteliminatorusesanoilseal,theinsulatingoildirectlycontactstheoutsideairandthefurnacegas,sodust,acidmist,moisture,andthelikeenter,andtheinsulationbecomesverybad.Sincetheliquidleveldischargeorsuspendeddustbridgeflashesandcannotapplyahighvoltage,fireanddischargemayoccur,andafiremayoccur.Therefore,insulationoilwithgoodinsulationshouldbeusedasmuchaspossible.Inaddition,itisnecessarytoperformtheinsulationendurancetestandtheoperationofremovingthemixedmoistureregularly.Theinsulatingoilafterlong-termuseneedstobereplacedandregeneratedoncein1to2yearsduetodeteriorationofinsulationcapacity.(6)InsulatingporcelainbottlesDestructionandcrackingofinsulatedporcelainbottlesoccurfrequently,whichmayresultintheinabilitytoapplyhighvoltageorpower.Thereasonisasfollows.Condensationleakage:Sincethetemperatureofthedustcollectionchamberisreducedduringoperation,SOscondenseonthesurfaceandleakageoccursfrequently,soitmustbeoperatedatanappropriatetemperature(outlet300°C).Destructionduringinstallationwork:Caremustbetakenduringinstallationwork,andcaremustbetakennottobumporinstallproperly.(7)ReplacementofdischargeelectrodeThedischargeelectrodeoftheleadelectricmisteliminatorisbrokenduetodustadhesion,formationoftheinsulatingfilmandcorrosion,poorinstallationquality,orreplacementduetoimpossiblecorrectionofbending.Whensulfuroreandzincoreareused,thedischargeelectrodeoftenhasaninsulatingfilm.Itisusuallyreplacedonceevery1-5years.Thereasonwhythedischargeelectrodeofthedefoggingdeviceisreplacedisalsogenerallyrequiredtobereplacedwhenthestar-shapedprotrudingportionofthedustremovingdeviceisseverelydamaged.Thedesulfurizationdustcollectorregularlycleanstheaccumulatedashinthesedimentationtankandkeepsthecleanlinessofthecirculatingwaterasmuchaspossible.Ifthedesulfurizationefficiencyisrequiredtobeabove80%,thelyemustbeaddedtothecirculatingpoolatregularintervalstokeepthePHvalueofthecirculatingwaterat9orabove.Inthesedimentationtank,theacidicwastewaterandtheaddedalkaliwaterandtheprecipitatearefilteredandrecycled.Thetemperatureoftheleaddefoggerdependsontwofactors,thefirstisthemaximumtemperatureofthefiltermaterial,andthesecondisthatthegastemperaturemustbeabovethedewpointtemperature.Atpresent,duetothelargeselectionofglassfiberfiltermaterials,themaximumusetemperaturecanreach280°C,forthegasabovethistemperaturemusttakecoolingmeasures,forthegasbelowthedewpointtemperaturemusttakewarmingmeasures.Atpresent,therearemanyPPSfiltermaterials,andthet
