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1、Unit1UnitOperationsArp26th，2011Ying,Xiaoguanglesson1ClassificationofUnitOperationsFluidflowThisconcernstheprinciplesthatdeterminetheflowortransportationofanyfluidfromonepointtoanother.HeattransferThisunitoperationdealswiththeprinciplesthatgovernaccumulationandtransferofheatandenergyfromonep

2、lacetoanother.EvaporationThisisaspecialcaseofheattransfer,whichdealswiththeevaporationofavolatilesolventsuchaswaterfromanonvolatilesolutesuchassaltoranyothermaterialinsolution.DryingInthisoperationvolatileliquids,usuallywater,areremovedfromsolidmaterialsDistillationThisisanoperationwherebyco

3、mponentsofaliquidmixtureareseparatedbyboilingbecauseoftheirdifferencesinvaporpressure.AbsorptionInthisprocessacomponentisremovedfromagasstreambytreatmentwithaliquid.MembraneseparationThisprocessinvolvesthediffusionofasolutefromaliquidorgasthroughasemipermeablemembranebarriertoanotherfluid.Li

4、quid-liquidextractionInthiscaseasoluteinaliquidsolutionisremovedbycontactingwithanotherliquidsolventwhichisrelativelyimmiscible(不混溶的)withthesolution.Liquid-solidleaching(浸提)Thisinvolvestreatingafinelydividedsolidwithaliquidthatdissolvesoutandremovesasolutecontainedinthesolid.CrystallizationT

5、hisconcernstheremovalofasolutesuchasasaltfromasolutionbyprecipitating(沉淀)thesolutefromthesolution.MechanicalphysicalseparationTheseinvolvesseparationofsolids,liquids,orgasesbymechanicalmeans,suchasfiltration,settling,andsizereduction,whichareoftenclassifiedasseparateunitoperations.Lesson2Fra

6、ctionaldistillationFractionaldistillationistheseparationofamixtureofcompoundsbytheirboilingpoint,byheatingtohighenoughtemperatures.FractionalDistillationinaLaboratoryApparatusconicalflask1.Theapparatusisassembledasinthediagram.Themixtureisputintotheroundbottomedflaskalongwithafewantibumpingg

7、ranules(沸石),andthefractionatingcolumnisfittedintothetop.2.Asthemixtureboils,vaporrisesupthecolumn.Thevaporcondensesontheglassplatformsinsidethecolumn,andrunsbackdownintotheliquidbelow,refluxingdistillate.3.Onlythemostvolatileofthevaporsstaysingaseo