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CatalystMarketShareinJapan日本的催化剂市场份额Coal-FiredBoilers燃煤锅炉•Honeycombcatalysthasoperatedover100,000hourswithoutreplacement.蜂窝式催化剂运行超过100,000小时无替换•Demonstratesexcellentresistancetopoisoning,erosion,andplugging.优异的防毒、防腐、防堵塞表现67%33%蜂窝式HC平板式PlateCatalystMarketShareinGermany德国的催化剂市场份额Coal-FiredBoilers燃煤锅炉•Honeycombdominatesduetoefficientcellstructureandsuperiorperformancelife.蜂窝式催化剂由于有效的结构和超群的性能最终占据了市场主导地位.DryBottomHoneycomb蜂窝式DryBottomPlate平板式WetBottomHoneycomb蜂窝式WetBottomPlate平板式65%15%12%8%AdvantagesofCormetechHighPerformanceHoneycombCatalystversusPlateCatalystCormetech蜂窝式催化剂和板式催化剂比较Product产品Pitch,mm孔径GeometricSurfaceArea,m2/m3比表面积RelativeVolumerequired*需要的体积PlateCatalyst板式5.5–7.0307–353176%-153%CormetechHoneycombCM-69HP蜂窝式6.9(22-cell)539100%*AtConstantNOxConversionEfficiency(90%),AmmoniaSlip(2ppmvd@3%O2)andSO2Oxidationrate(0.9%)MechanismofAshAccumulation积灰的机理BridgepluggingcausedbylargedustagglomeratesGenerationofcoarseashaftercombustionEntrainedingasstreamtocatalystReleaseandfalloncatalystsurfaceCohesionoffineashtoformagglomeratesDepositionoffineashatstaticflowregionsupstreamBridgepluggingcausedbylargedustagglomerates由大团灰分搭桥导致堵塞Generationofcoarseashaftercombustion燃烧形成大颗粒灰分Entrainedingasstreamtocatalyst大颗粒灰随烟气到达催化剂Releaseandfalloncatalystsurface松动并坠落在催化剂表面Cohesionoffineashtoformagglomerates细灰凝聚成块Depositionoffineashatstaticflowregionsupstream细灰在上游层流层沉积UnderstandingAshCharacteristics了解灰分的特性•AngleofRepose.积灰角–PSD.灰分粒径分布–Surfacechemistry.表面化学–Surfacefriction.表面摩擦系数WHAlpha=AngleofRepose=2H/WFunnel漏斗Ash灰GermanPlantExperience:System/FlueDesignNotOptimized系统设计未优化GasFlowFromBoiler锅炉烟气Shallowflueentranceangle角度太小Lowvelocityoverloadrangeduetoimproperentrancefluesize由于入口设计问题,导致烟气流速过缓Rectifier整流层Catalyst催化剂AshAccumulation积灰InitialCatalystwasunit1Honeycombunit2PlateLongleadingedgeturningVanes长导流叶片一号机为蜂窝式,二号机是平板式GermanPlantExperience:PoorDesignResultedinSevereProblems不良设计导致严重问题•Combinationof:问题包括•“Sticky”flyash飞灰粘性大•Poorflueandvanedesign烟道和叶片设计不好•Resultincatalystplugging导致催化剂堵塞•Pluggingoccurredonbothunits-Honeycombandplatearesimilarinpoorlydesignedsystem•说明在系统设计不好的情况下,蜂窝式和板式催化剂都会发生堵塞现象.GermanPlantExperienceUtilityForcedToChangeSetup业主被迫改变设计•ContinuedoperationwithmixtureofplateandHoneycomb持续运行一段时间以后•Firesoccurredduetoashaccumulation积灰着火•Platemeltedandspreadfire板式催化剂融化,火势蔓延•FireextinguishedatHoneycomblayer在蜂窝式催化剂上的火熄灭•Utilitydeterminedtofixsituationby:业主决定通过以下方式解决问题•Partialfixoffluedesign改变烟道设计•Changeallcatalysttolargepitchhoneycombtocompensateforpartialfixoffluedesign全部换用大孔径蜂窝式催化剂GermanPlantExperienceFlueDesignFix烟道设计改变Addedflowstraightenerandperforatedplatetoincreasevelocity增加直板导流装置增加流速GasFlowFromBoiler锅炉烟气Shallowflueentranceangle锐化烟道进角Rectifier整流层Catalyst催化剂RemovalofGuidevanes拆除导流叶片Catalystchangedto15/16cellHoneycomb换用15/16孔蜂窝式催化剂AshPluggingTest堵塞试验•Purpose:Toconfirmthetendencyofashpluggingonvarioustypesofcatalystincludingrectangularpitchandplatecatalyst.目的:确认各种类型催化剂的堵塞倾向,包括板式催化剂的矩形孔•Typeofcatalystmodeltested:试验使用的催化剂模型OpenArea/开孔率Pitch/opening孔径和内孔直径Type/类型3x26Catalyst80%6.0mmPlate板式16x16Catalyst79%9.2mm/8.4mmHoneycomb蜂窝21x21Catalyst73%7.1mm/6.4mmHoneycomb蜂窝AshPluggingTest堵塞试验•AshSample(灰样):–Inordertoincreaseashviscosity,flourwasaddedtotheashsampleasindicatedbelow–为了增加灰的黏性,在灰样里面添加了面粉Ash/灰Flour/面粉ReposingAngle/28%72%52°(atR.T.)Roomtemperature0%10068°(atR.T.)AshPluggingTest堵塞试验TestCondition测试条件0%Ash/100%FlourCatalystModel催化剂OpenArea开孔率Pitch孔径Type类型150grams3x26Catalyst80%openarea6mmPlate板式~21%Plugged16x16Catalyst79%openarea9.2mmHoneycomb蜂窝~6%Plugged21x21Catalyst73%openarea7.1mmHoneycomb蜂窝~10%PluggedAshPluggingTest堵塞试验•Results结果:TestCondition28%Ash/72%FlourCatalystModel催化剂OpenArea开孔率Type类型250grams3x26Catalyst80%openareaPlate板式~12%Plugged16x16Catalyst79%openareaHoneycomb蜂窝~1%Plugged21x21Catalyst73%openareaHoneycomb蜂窝~18%PluggedDustPropertiesAshLoadingComparison灰分特性/灰分负荷比较Example例子AshLoading灰分负荷g/Nm350Flow流量Nm3/hr1,756,000Area面积m2233.2Comparison比较Example例子Data数据Ash灰Flour面粉Flour/Ash混合物Area面积m2233.20.02250.0225AshLoading灰分负荷g/s24,389150250AshLoading分年负荷g/m21056,66711,111AngleofRepose°Unavailable68°52°PlateCatalystAshPluggingversusHoneycombCatalystAshPlugging积灰特性比较-蜂窝对比板式•AshPluggingTestingdonehasrevealedthatplatecatalystisjustaslikelytohavepluggingoccurduetohighashloadingasisthecasewithhoneycombcatalyst堵塞试验证明蜂窝和板式在高灰分工况下有同样的堵塞可能性•PlugginghasoccurredinbothplateandhoneycombcatalystunitsthroughouttheUnitedStates在美国蜂窝式催化剂和板式催化剂均有堵塞现象出现LPAExamination大粒径灰检测ElementPostMortem:大粒径灰堵塞后的催化剂CormetechExperiencewithCoalsContainingHighLevelsofCaOCormetech针对高钙煤的经验CaODeactivationMechanismCaO的劣化机理ThedeactivationisratelimitedbyCaOdeposition劣化的速度取决于CaO沉积的速度•Step1–CaOiscaughtonthecatalystsurface–ProcessisdependentonavailabilityandadhesionofCaO•Ratecontrollingprocessfordeactivation•Veryslowconcentrationchanges(~104hours)CaOCaOcatalystsurfaceCaOactivesites•Fastreactiontime(~101hours)•Step2–SO3bonding&diffusion–ProcessisfunctionofmasstransferandconcentrationCaOactivesitesSO3catalystsurface•Step3–DiffusionandexpansionCaO+SO3CaSO4–Reactionisafunction
本文标题:催化剂调查
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