氟磷灰石高温热分解特性与机理

22220034Vol.22No.2JournalofLiaoningTechnicalUniversityApr.20032002-08-215987603619990222111964-1008-0562(2003)02-0145-031.,123000;2.,310027800~1200=771kJ/molA=7.40.5min-1TQ535AStudyonpyrolysisandkineticsoffluorineemissionoffluorapatiteathightemperatureQIQing-jie1LIUJian-zhong2WANGJi-ren1CAOXin-yu2ZHOUJun-hu2CENKe-fa2(1.CollegeofResourceandEnvironmentEngineering,LiaoningTechnicalUniversity,Fuxin123000,China;2.CollegeofMechanicalandEnergyEngineering,ZhejiangUniversity,Hangzhou310027,China)AbstractThestudyonpyrolysisbehavioroffluorinemineralsincoalisanimportantresearchmethodforfluorineemissionduringcoalscombustion.Inthepaper,thefluorinepyrolysischaracteristicsandkineticsmechanicsoffluorapatitemineralatelevatedtemperatureswerestudiedsystemicallyforthefirsttimebygaseousfluoridesdirectabsorptionandfluorideion-selectiveelectrodemeasurementtechnique.Theresearchresultshaveshownthattheheatingtemperature,heatingtimeandairmoisturehaveremarkableeffectonthepyrolysisrateoffluorapatitemineral.Kineticscalculationhasshownthatpyrolysisreactionwasfirstorderandtheactivationenergyforthepyrolysiswas771kJ/mol,applicableovertherange800~1200Theresearchresultswillbeofsignificanceforfluorineemissionmechanism,controltechnologyduringcoalcombustionandphosphoricfertilizerproductionprocess.Keywordsfluorineincoalpyrolysishightemperaturedecomposeinfluencefactorskineticsmechanics[1]Crossley[2]M10X2(RO4)6,RPASVXFClOHMCaMgSrM10(OH)2-xFx(PO4)6,0x2FOHFOHX=2M5(PO4)3FX=1M10(PO4)6(OH)F2214670080090010001100120013001400020406080100/%/oC,t=30min,Q=800ml/min1Fig.1influenceofheatingtemperatureonthefluorineemissioninatmospheric0204060801001200204060801001350oC1200OC1000OC800OC/%/min,Q=800ml/min2Fig.2influenceofheatingtimeonthefluorineemissionFClOH[3]Garcia-Labiano[4]125804ìg/g200[5]2.12.1.1[3]25mg150mg20mg2.1.21217158005.7%100034.7%22.1.331200800ml/min)()(FF-⇒-21476.57.07.58.08.59.09.5-7.0-6.5-6.0-5.5-5.0-4.5-4.0lnkT-110-4/K-14lnk-1/TFig.4lnk-1/Tspeactraofpyrolysisoffluorapatite120min20.0%120min84.2%120min98.7%020406080100120020406080100/%/minT=1200,Q=800ml/min3Fig.3influenceofairmoistureonthefluorineemission()nktaa-=1dd2aknt800~1200)1ln(a--tArrheniusRTEAek-=3AEklnT/14r=0.99866,800~1200E=771(kJ·mol-1A=7.40.51min-()aa-⎟⎠⎞⎜⎝⎛-=19267exp4.7ddTt4[5]41.4~59.2(kJ·mol-177(kJ·mol-1123800~1200=771(kJ·mol-1A=7.40.5min-1[1]DemirI,RuchRR,DambergerHHetal.EnvironmentallycriticalelementsinchannelandcleanedsamplesofIIlinoiscoal[J].Fuel,1998,77(1):95-107.[2]CrossleyHEJ.TheDeterminationofFluorineinCoal[J].JournaloftheSoc.Chem.Ind.,194463(2):289-292.[3]GodbeerWCSwaineDJ.FluorineinAustralianCoals[J].Fuel198766(6)794-798.[4]Garcia-LabianoF,HampartsoumianE,WilliamsA.DeterminationofSulfurReleaseandItsKineticsinRapidPyrolysisofCoal[J].Fuel,1995,74(7):1072-1079.[5].[D].2002.