高效复合型塔板及其在碳化塔中的应用 外文翻译 过程装备与控制工程

内蒙古科技大学本科生毕业设计英文翻译学生姓名XXX学号XXX专业过程装备与控制工程班级装备XX2班指导教师XXEFFICIENTCOMPOUNDPLATEINCARBONATINGTOWERABSTRACTEFFICIENTCOMPOSITEPLATEUSINGASIEVEANDTHINLAYERCOMPOSITESTRUCTUREOFTHESTRUCTUREDPACKING,THEREARETWOTYPESOFCOMPOSITEFILLINGSORIFICEANDDJTYPEPLATECOMPOSITEFILLINGSTHECOMPOSITESTRUCTUREMAKEFULLUSEOFTHESPACEBETWEENTHEPLATEANDIMPROVETHEGASLIQUIDDISTRIBUTIONOFTHETOWER,INHIBITEDENTRAINMENTINTHECUBICLE,TOIMPROVETHEOPERATINGFLEXIBILITY,ANDHASANEXCELLENTHYDRODYNAMICPERFORMANCEANDMASSTRANSFERPROPERTIESWEARINGAFLOWTYPECOMPOSITEPLATETOSUBSTITUTIONTHELINDEBLISTERANDTHEGENERALSIEVEORVALVETRAYSINTHERECTISOLTHEMETHANOLDISTILLATIONCOLUMNTOIMPROVETHESEPARATIONEFFICIENCYOFMORETHAN20PERCENT,ANINCREASEOFPROCESSINGCAPACITY,REDUCINGTHEREFLUXRATIOIMPROVETHECORROSIONPROBLEMSAVETHEENERGYCONSUMPTIONOFTHESYSTEMWEARAFLOWTYPECOMPOSITEPLATEALSOSUCCESSFULLYAPPLIEDTOTHEMETHANOLPRODUCTIONPLANTDISTILLATIONCOLUMNSYSTEMINMETHANOLTHREETOWERDISTILLATIONCOLUMN,THECRUDEDISTILLATIONTOWERANDTHERECTIFYINGSECTIONPRESSUREDISTILLATIONCOLUMNFLOWTHROUGHTHECOMPOSITEPLATE,STRIPPERSEGMENTFLUXELASTICGOODDJTYPECOMPOSITEPLATETOACHIEVETHEBESTCOMBINATIONTOMEETTHEREQUIREMENTSOFTHETOWEROPERATINGCONDITIONSKEYWORDSPLATEEFFICIENCYCOMPOUNDMETHANOLDISTILLATIONAPPLICATION1INTRODUCTIONPLATECOLUMNHASDEVELOPEDHUNDREDSOFTYPES,SUCHASSIEVE,FLOATVALVE,FIXEDVALVEVSTREGARDLESSOFWHATKINDOFPLATEMUSTHAVEACERTAINAMOUNTOFPLATESPACING,CANBESEPARATEDTOENSURETHATTHELIQUIDSMOOTHOBSCENE,GASENTRAINEDENTRAINMENTOVERTHELASTDECADE,THEREASONABLEUSEOFTHESPACEBETWEENTHEPLATEANDBECOMEANISSUEOFCONCERNAMONGTHEM,THECOMPOSITEFILLERTECHNOLOGYHASDEVELOPEDRAPIDLYINTHETRAYMILLER,CHUANG,INTHERECTANGULARDOWNTUBEPLATECOMPOSITEFILLERLAYER,PARTICULARLYLARGEOPENINGRATEOFTHESIEVEINAPARTIALCROSSFLOWTHATIS2070OFTHELEAKAGESTATEWORKCHUANGALSODOWNCOMERPIPEONBOTHSIDESOFOPENINGSTOALLOWLIQUIDFILLERLAYERFROMTHESIDEOFTHESHEDAREPARTOFTHECROSSFLOWPLATECONTROLTRAYWEEPINGANDOVERFLOWDOWNCOMERSAMOUNTOFFLUIDHASSOMEDIFFICULTIESOPERATIONALDISTRICT,OPERATINGFLEXIBILITYTHISARTICLEDESCRIBESTHEPERFORMANCEOFTHESETWOCOMPOUNDTRAYSANDTHEIRAPPLICATIONINTHEMETHANOLDISTILLATION2WEARAFLOWTYPECOMPOSITEPLATE21WEARTHESTRUCTURALCHARACTERISTICSOFTHEFLOWCOMPOSITEPLATEWEARAFLOWTYPECOMPOSITEPLATEORIFICEADDALAYERHIGHAS50TO150COFFEESTRUCTUREDPACKINGCOMBINATION,SHOWNINFIGURELPLATESPACINGOFTHECOMPOSITEPLATETHANTHEAVERAGEPLATESMALL,ABOUT300TO450MM,NODOWNCOMERSWEARFLOWPLATESIEVETYPE,VALVETYPETHEMESHCANBECREATEDCANALSOBEUNEVENLYOPENED,OROPENINGOFDIFFERENTSIZESDIFFERENTAPERTUREEXPERIMENTALSTUDIESHAVESHOWNTHATTHESIMPLESTUNIFORMOPENEDSIEVEPLATE,YOUCANOBTAINAUNIFORMLIQUIDLAYERANDTHEGASLIQUIDCONTACTCONDITIONFIG1复合塔板22WEARTHEHYDRODYNAMICPERFORMANCEOFFLOWCOMPOSITEPLATEWEARAFLOWTYPECOMPOSITEPLATEWITHACOMPLEMENTARYGOODHYDRODYNAMICPERFORMANCEEMBODIEDINTHEFOLLOWINGASPECTSACOMPOSITEFILLERLAYERHASBECOMEAGASDISTRIBUTIONPLATEWALLFLOWEFFECT,WEARTHEUNEVENDISTRIBUTIONOFGASFLOWPLATE,RESULTINGINUNEVENPANELLIQUIDLAYERTHICKNESSANDFLOWDISTRIBUTIONWHICHISCAUSEDBYCROSSFLOWTRAYEFFICIENCYISNOTTHEMAINREASONCOMPOSITEFILLINGS,THESTRUCTUREDPACKINGOFCROSSCUTTINGCHANNELSSEPARATEDBYTHEGASTOBEREDISTRIBUTION,THEREBYELIMINATINGTHEDIFFERENCEOFTHEBOARDOFTHELIQUIDLAYERTHICKNESSBCOMPOSITEFILLERLAYERPLAYEDATRAPENTRAINMENTENTRAINMENTISANIMPORTANTFACTORAFFECTINGTRAYEFFICIENCYTHECOLBURNASSOCIATEDWITHEXPRESSIONOFTHEENTRAINMENTAFFECTTHEEFFICIENCYOFTHEQUANTITATIVERELATIONSHIPVLEEVMS/1FOREXAMPLE,INTHEDISTILLATIONCOLUMN,THEREFLUXRATIOR2,THELIQUIDGASRATIOIS2/3,ENTRAINMENTFLOODINGPOINTWAS80,IE008KGPERKILOGRAMOFGASENTRAINEDLIQUID,WHENTHEDRYPLATEEFFICIENCYOF85ONLY771OFTHETOTALENTRAINMENTEFFECTSOFWETPLATEEFFICIENCYTHATTHELOSSOFNEARLY8EFFICIENCYVISIBLE,THEIMPACTOFENTRAINMENTONDISTILLATIONPLATEEFFICIENCYGENERALDISTILLATIONTRAYDESIGN,INORDERTOREDUCEENTRAINMENT,THELIMITINGAPERTUREANDGASSPEEDTOENSUREADEQUATEPLATESPACINGCOMPOSITEFILLERLAYER,ENTRAINMENTDECLINEDSHARPLYFIGURE2SHOWSTHECOMPARISONOFTHEEXPERIMENTALLYDETERMINEDWITHANDWITHOUTCOMPOUNDPACKINGSIEVEMISTENTRAINMENTAMOUNTTHEREFORE,THESMALLPLATESPACINGTHANTHEGENERALPLATEWEARFLOWTYPECOMPOSITEPLATEMORETHAN30FIG2雾沫夹带对比曲线CORIFICEANDATHINLAYEROFFILLERLAYEROFLIQUIDDISTRIBUTIONTHELIQUIDDISTRIBUTIONOFTHEFILLERLAYERISVERYCRITICAL,ANDGENERALREQUIREMENTSFORLIQUIDDISTRIBUTIONCANPROVIDEADISTRIBUTIONPOINTINMORETHAN100PERSQUAREMETERPERSQUAREMETERONTHESIEVEATLEASTL000SIEVE,PRESSHALFOFTHELIQUIDCHANNELPERSQUAREMETEROF500POINTSSEENWEARINGAFLOWTYPECOMPOUNDTRAYFILLERLAYERHAVETHEBESTLIQUIDDISTRIBUTION23WEARTHEMASSTRANSFERPERFORMANCEOFSTREAMINGCOMPOSITEPLATEWEARINGAFLOWTYPECOMPOSITEPLATEGASLIQUIDMASSTRANSFERCANBEDIVIDEDINTOTRAYSOFBUBBLEZONE,GASLIQUIDCONTACTAREAOFSTRUCTUREDPACKINGANDPACKINGTHESPACEBELOWTHESHOWERDOWNTHETHREEDISTRICTSSHOWNINFIGURE3FIG3复合塔板的操作状态示意L穿流筛板；2规整填料；3鼓泡区；4淋降区5液膜区EXCELLENTHYDRODYNAMICPERFORMANCEOFFLOWTHROUGHCOMPOSITEPLATECANBEINFERREDTHEMASSTRANSFERAREAINTHESTATEOFTHEGASLIQUIDCONTACTANDBACKMIXINGLESSGOODMASSTRANSFERBYDISTILLATIONEXPERIMENTALSTUDYSHOWEDTHATWEARINGAFLOWTYPECOMPOUNDTRAYTHANTRAYEFFICIENCYOF30TO50FIGURE4SHOWSTHECOMPARISONOFWEAROFTHEMASSTRANSFEREFFICIENCYOFTHEFLOWTYPECOMPOSITEPLATEWITHTHEGENERALSIEVEWEARINGAFLOWTYPECOMPOSITEPLATEPLATEEFFICIENCYISGENERALLY90TO100ATTHEPEAKOFTHEEFFICIENCYCURVEUPTO110AMONGTHEM,THETOWERBOARDFOAMLAYERANDTHEFILLERLAYERCONTRIBUTIONTOTHEMASSTRANSFEROFMORETHAN90OF,POURINGDOWNAREASAREGENERALLYPLAYED10OFTHEMASSTRANSFER3DJTYPECOMPOSITEPLATE31DJTYPESTRUCTURALCHARACTERISTICSOFTHECOMPOSITEPLATEDJTRAYISAMULTIDOWNCOMERTRAYS,DEPENDINGONTHESIZEOFTHELIQUIDLOAD,YOUCANSETONEORMOREROOTRECTANGULARDOWNCOMERDOWNCOMERARRANGEDTRAYSMIDDLE,DOWNCOMERSOFADJACENTTRAYSEACHOTHERINTOA90ARRANGEMENTAROUNDTHEDOWNCOMEROVERFLOWPERIPHERYOVERFLOWWEIRTHANTHEAVERAGEPLATE25TIMESASLONGDOWNCOMERSUSPENSIONINTHEGASSPACEBYTHELIQUIDAREAOPENINGSBUBBLINGBYTHELIQUIDZONEOUTSIDEOFTHEDJTRAYISALSOEQUIPPEDWITHASPOILER,INORDERTOIMPROVETHEFLOWPATTERNSOFLIQUID,THELIQUIDRESIDENCETIMEDISTRIBUTIONISMOREUNIFORMSETINTHEDJTRAYOFLIQUIDANTISHOCKDEVICELEAKAGE,REDUCINGTHESHORTCIRCUITCAUSEDBYTHEIMPACTOFLEAKAGEFIGURE5SHOWSTHEBASICSTRUCTUREOFTHEDJTRAYFIGURE6ISAPREASSEMBLEDPHOTOSOFTHEDJTRAYFIG4穿流复合塔板效率曲线FIG5DJ型塔板的结构FIG6DJ型塔板照片AIRCOMPOSITEFILLERTECHNOLOGYUSEDINTHEDJTRAY,CONSTITUTEACOMPOSITEPLATESHOWNINFIGURE7DJ1ALSOKNOWNASDJ3TRAYSCOMPLEXHOMESTOFILLDEFENSEPACKEDINSPECIALLYDESIGNEDPACKINGBASKETPULLXUANFIXEDINTHETRAYBELOW,FILLBASKETSANDTRAYSTOLEAVESOMESPACELIQUIDAREALLBASICALLYFROMTHEDOWNCOMEROVERFLOWCOMPOSITEFILLINGSFROMTHEINHIBITIONOFTHEFOGZHUENTRAINMENTANDIMPROVETHEROLEOFGASDISTRIBUTIONFIG7DJ型复台塔板32DJSCOMPLEXPRAISEPLATEPERFORMANCEFEATURESDJTYPECOMPOUNDTRAYLOADCHARACTERISTICDIAGRAMOFTHEEXPRESSIONOFTHEHYDRODYNAMICPERFORMANCESHOWNINFIGURE8FIG8DJ型塔板负荷性能SINCETHEHANGINGDOWNCOMERBOTTOMOFTHEDOWNCOMERCANNOTALLBEOPENTOTHESEALPLATEBYOPTIMIZINGTHEAREAOFTHECLOSUREPANELOPENING,ITISNECESSARYTOENSURETHATTHELIQUIDUNIMPEDEDREDUCETHEFLOWRESISTANCEBUTALSOTOENSURETHATTHELIQUIDSEALDOESNOTBRAGGASDIFFICULTIESOFTHIS,MORETHANONEDOWNCOMERSELFSTYLEDLINEINFIGURE7NORMALOPERATINGAREAINTHERIGHTOFSELFSTYLEDLINELOWERLIMITIGNORANTOFTHELEAKAGELINE,THEREAREASELFSTYLEDLINEOFOPERATIONOPERATIONOFLOWERRESISTANCELEAKAGELINEANDSELFSTYLEDLINE,WHICHEVERISOPERATINGCAPANDPLATEISNODIFFERENT,BUTALSOTHEDOWNCOMERFLOODINGLINESANDEXCESSIVEENTRAINMENTLINEBECAUSECOMPOSITEFILLINGSINHIBITENTRAINMENT,FIGURE8,THEEXCESSIVEENTRAINMENTLINEISMUCHHIGHERTHANTHEDOWNCOMERFLOODINGLINETHEUPPERCONTROLLIMITOFTHETRAYDOWNCOMERFLOODINGLINEDJTYPECOMPOSITEPLATEWITHHIGHTHROUGHPUTCHARACTERISTICSOFTHEGENERALWELLTYPETOWERYINGANDAIRCOMPOSITEFILLINGSBRINGGREATEREFFICIENCYANDGREATEROPERATIONALFLEXIBILITYFIGURE9SHOWSAFOGSOOENTRAINMENTCOMPAREDWITHANDWITHOUTCOMPOSITEFILLINGSFIGURE10SHOWSTHEMEASUREDFORETHANOL,AWATERSYSTEMINTHEHEATMOLDDEVICE300WITHOUTCOMPOUNDFILLERTRAYEFFICIENCYCOMPARISONSEEFIGURECHOCOMPOSITEFILLINGSCANGREATLYREDUCETHEAMOUNTOFENTRAINMENTCANIMPROVETHETRAYEFFICIENCYOF10TO15CANALSOSEETHEFIGURE,APARTICULARLYHIGHEFFICIENCYINTHEOPERATIONTHELOWEREND,WHICHINDICATESTHATWHENTHEWHENSIEVERANDOMLEAKAGE,COMPOSITEFILLINGSPROVIDEAFURTHERGASLIQUIDMASSTRANSFERFIG9加与不加复合填料的雾沫夹带对比FIG10加与不加复合填料的塔板效率4CONCLUSIONAWEARAFLOWTYPECOMPOSITEPLATETHINLAYEROFSTRUCTUREDPACKINGCOMPOUNDINTHETRAYBELOWEFFECTIVEUSEOFTHEGASSPACEBETWEENTHETRAYCROSSFLOWPLATEISEQUIVALENTTOTHELIQUIDDISTRIBUTIONOFTHEFILLERLAYERPLAYAUNIFORMDISTRIBUTIONOFLIQUIDMASSTRANSFERIMPROVETHEPACKINGLAYERTHEFILLANDPLAYGASDISTRIBUTIONROLEIMPROVETHETRAYSOFBUBBLING,STRENGTHENTHEOFTRAYSBUBBLINGLAYERMASSTRANSFERFILLERLAYERINHIBITSTHEENTRAINMENTPLATEQ,REDUCINGTHEBACKMIXINGBETWEENTHEBOARD,TOIMPROVETHETRAYEFFICIENCYCOMPAREDWITHTHEGENERALTRAY,TRAYEFFICIENCYCANBEINCREASEDBY30TO50,PLATESPACINGDECREASEDBY30,ISCURRENTLYTHEMOSTEFFICIENTPLATEBTHEDJWILLBEDJTYPEPLATEWITHTHETHINLAYEROFFILLERCOMPOSITEWITHFILLERLAYERINHIBITSTHEENTRAINMENTIMPROVETHEGASDISTRIBUTIONDJTYPECOMPOSITEDJTRAYANDHIGHTHROUGHPUTFEATURES,HAVEAIRCOMPOSITEFILLEREFFICIENCYANDOPERATINGFLEXIBILITYADVANTAGES,BUTALSOHASHIGHTHROUGHPUT,HIGHEFFICIENCY,HIGHFLEXIBILITY,AGOODPLATECHIGHERCOMPOSITEPLATEUSEDINALARGEFERTILIZERRECTISOLDEVICEMETHANOLDISTILLATIONCOLUMNANDMETHANOLPRODUCTIONPLANTDISTILLATIONCOLUMNSYSTEMWASABIGSUCCESSREFERENCES1MILLER,ETALAPPARATUAFORCONTACTINGALIQUIDWITHAGASP,UNITEDSTATENTUS005244604,19932CHUANG,ETALMULTIPLEDOWNNCOMERFRACTIONATIONTRAYHAVINGPACKINGBETWEENDOWNCOMERP,UNITEDSTATESPATENTUS005366666,19943YAOKEJIAN,WISHBELLYU,TOTALBUILTBING,ETCTHEDEVELOPMENTOFTHECOMPOSITEPLATEANDITSINDUSTRIALAPPLICATIONSJPETROCHEMICAL,2000,29107727754XIAOMEIYU,TIANJUN,ZHUJINZHONGAIRCOMPOSITEFILLERPLATEP,THECHINESEINVENTIONPATENTATZL97103868,619995XIAOMEIYU,ZHUBELLYU,YAOKEJIANPLATEFILLERSABSORBAPPLICATIONSTABILIZERDEPARTMENTJPETROCHEMICAL,2003,324321324高效复合型塔板及其在碳化塔中的应用摘要高效复合型塔板采用筛板和薄层规整填料的复合结构，有穿流筛板复合填料和DJ型塔板复合填料两种型式。复合结构充分利用了塔板间的空间，改善了塔内的气液分布，抑制了板间雾沫夹带，提高了操作弹性，具有优良的流体力学性能和传质性能。穿流型复合塔板在低温甲醇洗的甲醇精馏塔中成功地代换了林德泡罩和一般筛板或浮阀塔板，提高了分离效率20以上，增加了处理能力，降低了回流比。改善了腐蚀问题。节省了系统的能耗。穿流型复合塔板还成功地应用于甲醇生产装置的精馏塔系中。在甲醇三塔精馏塔系中，粗馏塔和加压精馏塔的精馏段采用穿流型的复合塔板，而提馏段则采用通量大弹性好的DJ型复合塔板，实现了最佳的组合，满足了塔内操作工况的要求。关键词塔板；高效复合；甲醇；精馏；应用1引言板式塔已发展了上百种型式，如筛板、浮阀、固定阀、垂直筛板等。不论哪一种塔板都必须有一定的板间距，以保证液体通畅下流，气体夹带的雾沫得以分离。近十几年来，如何合理利用塔板间的空间，成为大家关注的问题。其中，在塔板下复合填料的技术发展很快。MILLER、CHUANG等在矩形降液管塔板下复合填料层，采用特别大的开孔率，使筛板处于部分穿流即2070的漏液状态下工作。CHUANG还在降液管两侧开孔，让液体从侧面流人填料层。由于都是部分穿流的塔板。控制塔板的漏液量和溢流人降液管的液量有一定难度。可操作区比较窄，操作弹性小。本文将介绍这两种复合型塔板的性能以及它们在甲醇精馏中的应用。2穿流型复合塔板21穿流型复合塔板的结构特点穿流型复合塔板由穿流筛板下加一层高为50150咖的规整填料组合而成，如图L所示。复合塔板的板间距比一般塔板小，约为300450MM，不设降液管。穿流塔板可以是筛孔型的，也可以是阀型的。筛孔可以均匀开设，也可以不均匀开设，或开设大小不同的异孔径。实验研究表明，最简单的均匀开设的筛孔型塔板，就可以获得很均匀的液层和良好的气液接触状况。图1复合塔板22穿流型复合塔板的流体力学性能穿流型复合塔板具有互补的优良的流体力学性能。具体体现在如下几个方面A复合填料层成了塔板的气体分布器。由于壁流效应的影响，穿流塔板的气体分布不均匀，因而导致板上液层厚度和液流分布的不均匀。这也是造成穿流塔板效率不高的主要原因。复合填料后，规整填料相互交叉的分隔通道使气体得到重新分布，从而消除了板上液层厚度的差异。B复合填料层起到了捕集雾沫夹带的作用。雾沫夹带是影响塔板效率的重要因素，COLBURN关联表达了雾沫夹带影响效率的定量关系VLEEVMS/1例如在精馏塔中，回流比R2，则液气比为23，若雾沫夹带泛点率为80，即每千克气体夹带008KG液体，当干板效率为85时，计人雾沫夹带影响的湿板效率就只有771。也即损失了近8的效率。可见，雾沫夹带对精馏板效的影响很大。一般精馏塔板设计时，为了降低雾沫夹带，要限制孔径和气速，保证足够的板间距。复合填料层后，雾沫夹带急剧下降。图2表示了实验测定的加与不加复合填料的筛板雾沫夹带量对比。因此，穿流型复合塔板的板间距可比一般塔板小30以上。图2雾沫夹带对比曲线C穿流筛板成为薄层填料层的液体分布器。填料层的液体分布是十分关键的，一般要求液体分布器能提供每平方米100个以上的分布点。而筛板上每平方米至少有L000个以上的筛孔，按一半为液体通道计，每平方米也有500个点。可见，穿流型复合塔板的填料层有最优良的液体分布。23穿流型复合塔板的传质性能穿流型复合塔板的气液传质可分为塔板上的泡沫区、规整填料层内的气液接触区和填料下面空间的淋降区3个区如图3所示。图3复合塔板的操作状态示意L穿流筛板；2规整填料；3鼓泡区；4淋降区5液膜区根据穿流型复合塔板优良的流体力学性能，可以推论每个传质区都处于气液均匀接触和返混少的优良传质状态。通过精馏实验研究表明穿流型复合塔板可比一般塔板的效率提高3050。图4表示了穿流型复合塔板与一般筛板的传质效率对比。穿流型复合塔板的总板效率一般为90100，效率曲线的高峰处可达110。其中，塔板上的泡沫层和填料层对传质的贡献达90以上，淋降区一般起到10的传质作用。图4穿流复合塔板效率曲线3DJ型复合塔板31DJ型复合塔板的结构特点DJ塔板是一种多降液管塔板，根据液体负荷的大小，可设置一根或多根矩形降液管。降液管布置在塔板中间，相邻塔板的降液管互成90排列。由于降液管四周都是溢流周边。溢流堰比一般塔板要长25倍。降液管悬挂在气相空间受液区也开孔鼓泡。在DJ塔板的受液区外侧还装有导流板，以改善液体的流动模式，使液体停留时间分布更为均匀。在DJ塔板的受液区设置防冲击漏液装置，减少因冲击漏液造成的短路。图5表示了DJ塔板的基本结构。图6是预组装DJ塔板的照片。图5DJ型塔板的结构图6DJ型塔板照片将空中复合填料技术应用于DJ塔板，构成了如图7所示的DJ型复合塔板”1也称为DJ