简介:针对托普索S-200氨合成塔触媒更换时存在的问题,总结分析了本次触媒更换的现状,并指出合成塔中心筒断裂以及一段床触媒框严重变形为应注意的关键点。通过对合成塔内件的缺陷分析,为将来合成塔触媒更换指明方向。
简介:Chinahaslongbeenrecognisedasanimportantsourceofrefractoryrawmaterialsforrefractorymarketsworldwide.Bauxite,magnesia,fusedalumina,andrefractoryclaysinparticular,havemaintainedChina'sstrongpositionastheworld'sleadingsupplieroftheseminerals.However,importantchangeshavetakenplaceirthestructureofChineseandglobalsupplyoftheseminerals.Moreover,theworldrefractorymarketandthemineralstradingsectorhavealsoundergonearadicaltransformationthathasinfluencedmineralsupply,andshiftedendproductmanufacturetoChina.ThispaperhighlightsthesechangesandseeshowtheyhaveimpactedonChinaasaworldsourceofrefractoryminerals.
简介:Thedevelopmentofefficientbondingagentsisoneaspectoftheadvancementofrefractories.Basedonanewlydevelopedbindersystem,anewgenerationoftar-resinbondedmagnesiacarbonproductswithhighperformancehasbeendeveloped.Furthermore,thebindersystemcharacterizedbyhighcarbonyieldaftercarbonizationresultsinforminganextremelystrongcarbonbonding.Itcanimproverefractoriespropertiestogetnewproductwithmoreadvantagesthanoldrefractories:moreeconomic,lowercostandlowtoxicity.Tar-resinisnotonlyusedinshapedrefractories,butalsoinmorerefractoriestypes,suchasmonolithicrefractories.ImmersionexperimentsofMgO-Cmonolithicrefractoriessamplesinliquidsteelat1600℃havebeencarriedoutforsteelmakingindustry.TheseexperimentsshowedtheformationofadenseandcontinuousMgOrichlayer,ontheinterfacebetweenrefractoryandsteel,andthepossibleformationofinclusionsaslargeclustersprotrudingfromtherefractorysurface.Forthemechanicalproperties,thepowderwasheatedupto1400℃inairtoremovecarbon,andwassubsequentlyformedintobrickshape.StandardASTMwasusedtodeterminetheMOR,porosityanddensity.Itisfoundthatantioxidantmaterialsplayanimportantroleinimprovingthemechanicalproperties.
简介:Simplethree-pointbendingtestatambienttemperaturecharacterizedthemechanicalbehaviorofburnedAl2O3-Crefractoriesbeforeandafterthermalshockinassociationwiththeprocessingparameters(graphitecontentandcokingtemperature,etc.).Theresultsshowedthatnon-linearplastic-elasticbehaviorunderloadlowerthancoldmodulusofrupture(CMOR)wasregisteredinallspecimensandreallinearelasticbehaviorcouldbeidentifiedafterthefirstload.Thetotaldeformationcouldbedividedintotwoparts,plasticandelasticareas.ThegraphitecontentandjointbondingsystemofcarbonandceramicphaseswereresponsibleformechanicalbehaviorofAl2O3-Crefractories.
简介:MobarakehsteelCompanyproduces3milliontonsofsteelannuallywitheight180tonsEBTfurnaces.Differenttypesofmagnesia-carbonrefractorieshavebeenemployedatslaglineduringlast5years.InthepresentstudythewearandcorrosionofMgO-Crefractoriesofthesefurnaceshavebeenstudiedviapost-mortemanalysisofusedbricksandtheobservationofoperationaleffects.Laboratorycorrosiontestswerealsoarrangedtoinvestigatetheeffectofslagchemistryandthemechanismofchemicalcorrosion.Characterizationofdifferentmagnesia-carbonbricksclarifiedthatthecrystalsize,typeandchemistryofmagnesiaaswellasgraphitestructurehavethemaininfluenceoncorrosionresistance.TheCaO:SiO2ratioinslagalsoplaysavitalroleinthewearofslaglinerefractories.Theironoxidecontentofslagalsohasamajorroleingraphiteoxidation.Ofmetallurgicalparameters,theelectricpowerinputandthecontacttimehavegreatinfluenceonrefractorieslife.TheresultswillbediscussedwithemphasisonparticularoperationalfactorsinMobarakehsteelplant.
简介:Hexagonplate-likeAl8B4C7powdersweresuccessfullysynthesizedusingamixtureofdiborontrioxide,activatedcarbonandaluminumoraluminabyacarbothermalreductionprocess.TheeffectofAlsourceandstartingmaterialsadditionsonsynthesisofAl8B4C7wasinvestigated.ThephasecompositionandmicrostructureofAl8B4C7powderwerecharacterizedbymeansofXRD,SEMandEDS.ThemainphasecompositionsoftheproductssynthesizedfromAl,B2O3andactivatedcarbonareAl8B4C7andAl2OC.Al2O3canreplaceAltosynthesizeAl8B4C7.Al8B4C7grainssynthesizedfromAl2O3,B2O3andactivatedcarbonarehexagonplate-likeandhaveathicknessof10μmandasizeofabout100μm.