简介：Thecorrugatedpackingispronetobreakdowneasily,whichcanaffectthetowerefficiencysubstantially.Itistheinnerenvironmentofthevacuumdistillationtowerincludingthetemperatureandchemicalnatureoffluidthatleadtothepackingdamage.Thetheoreticalanalysisindicatesthatitistheinnermaterialflowofvacuumdistillationtowerthatleadstothevibrationofpacking,whichcanaffectthecorrosionfatigueofpackingsignificantly.Meanwhile,themodalshapeandinherentfrequencyofpackingunderprestresscanbeobtainedbymeansofmathematicalanalysis.Basedonthetwokindsofanalysis,theflowinducedvibrationandcorrosionfatigueareaccountableforthefailureofpacking.

简介：Anexperimentalinstallationofcoldmodelsimulationwassetuptostudythebedpressuredropindifferentregionsoffixedfluidizedbedreactorduringtopfeedingandbottomfeeding,respectively,atvariousgasvelocitieswiththefluidizationimageofsolidparticlesmonitoredatthesametime.Bycomparingthechangesinbeddensityandoperatinggasvelocityindifferentregionsoffixedfluidizedbedreactor,theinfluenceoftopfeedingandbottomfeedingpatternsonfluidizationbehaviorcouldbeinvestigated.Theresultsshowedthatthebeddensityintopfeedingreactorrespondedmorestablytothechangeingasvelocityalongwiththeadvantageofworkinginawiderrangeofoperatinggasvelocities.Basedonthisstudy,itisconcludedthatexistingbottomfeedingreactorconfigurationscannotmeetthefluidizationrequirements;andoptimizationofbottomfeedingreactorwillbeneeded.

简介：Thethermogravimetryanalyzercoupledwiththepyrolysisgaschromatography/time-of-flightmassspectrometrytechnologywasusedinthisstudytoinvestigatethemasslossbehaviorandvolatilereleasecharacteristicsofabituminouscoal.Theresultsshowedthatwithanincreasingheatingrate,thecharacteristicparametersandTG/DTGcurvesshiftedobviouslytothehighertemperatureregion.ThepyrolysisofabituminouscoalatdifferentheatingratescanbedividedintotwostagesaccordingtotheCoats-Redfern(C-R)plots.TheactivationenergyobtainedfromtheC-Rmethodis50.21—85.14kJ/moland5.14—7.24kJ/molataheatingraterangeof8—300℃/minforthefirstandsecondpyrolysisstages,respectively.Aromatichydrocarbonsweredominantinthevolatileproductsduringfastpyrolysisofthecoal,followedbytheolefins,whereasthephenolswerethethirdmajorcomponents.Withtheincreaseofpyrolysistemperature,theheavycomponentsinthevolatilespeciesincreased;meanwhilethephenolcrackingreactionswereintensified.Thecarbonnumberofolefinswasmainlyconcentratedin3—9,andthearomaticsweremainlycomposedofthecompoundsofC6—C13.Thisstudycanprovideabasicreferenceforfastpyrolysisofcoalandotherthermalchemicalconversionprocesses.

简介：Investigationsonthepyrolysisandkineticbehaviorsduringpyrolysisoffossilfuelsamples,suchascoal,arefundamentalfordevelopingtherelatedtechnologyandpracticalapplication.Inthiswork,pyrolysisbehaviorandkineticsinthepyrolysisprocessofacoalsamplewereinvestigatedbythethermogravimetricanalyzerataheatingrateof10,40,70,100,200,and500°C/min,respectively.ThepyrolysisprocesscouldbedividedintofourstagesaccordingtotheTG/DTGcurves.Thefirststagewasmainlyattributedtotheremovalofvolatiles,andthesecondpeakwasthepolycondensationreactionbetweenthevolatilecomponents.Itwasfoundthatmorevolatilescouldbereleasedfromcoalduringpyrolysisathigherheatingrateandthehigherpyrolysistemperaturewasnecessaryforarapidpyrolysisprocess.Kineticanalysisrevealedthatboththemodel-free(KASandFWO)andtheCoats-Redfernmethodsweresuitabletodescribingthepyrolysisprocess,andthevariationofactivationenergy(E)withthetwotypesofkineticmodelswasconsistentduringthewholepyrolysisprocess.Furthermore,theheatingratedidnotalterthereactionsequenceofthewholepyrolysisprocess,buthigherheatingratecouldmaketheEvalueoftheinitialpyrolysisstagesmaller.