【《气隙蒸馏装置的模拟仿真分析》12000字】

气隙蒸馏装置的模拟仿真研究目录TOC\o"1-3"\h\u27981摘要 15811绪论 2232951.1研究背景和意义 2182551.2题目研究方案和主要内容 499101.3气隙蒸馏装置的优势 6275651.4气隙扩散蒸馏的研究进展 9170721.5本文研究内容 117581气隙扩散蒸馏的基本原理 13143102.1气隙扩散蒸馏简介 13181932.2数学模型的建立 148684模型的假设： 1420720传热传质模型 1415127气隙蒸馏装置的模拟仿真 19136293.1MATLAB软件仿真原理 19619产水率 2030641造水比GOR 204703热损失率 2024578脱盐率 21139583.2仿真结果分析 2127488结论与展望 2932655研究结论 2922266研究展望 30摘要蒸馏是现代社会必不可缺的一项技术，它是人们获得淡水的主要手段。蒸馏装置有很多种，气隙蒸馏装置是其中一种高效而新颖的装置。它与传统的蒸馏不同，气隙蒸馏装置不仅结构紧凑、装置简单、操作方便，而且其工作在常压下，蒸馏热回收较容易，蒸馏热消耗低，装置的部件可由金属或非金属材料制成，制作成本较低。本文主要研究了气隙蒸馏装置的模拟仿真优化分析，首先基于传热原理，推导出总热流与不同影响参数之间的理论关系式，利用MATLAB软件进行建模，模拟了不同结构参数及进口参数对气隙蒸馏装置性能的影响，结果表明：发现产水率与气隙高度大致呈正比例的关系，随着气隙高度L的增大，产水率mf也不断增大；GOR与气隙高度大致呈正比例关系，随着气隙高度L的增大，GOR也不断增大；GOR的大小与气隙厚度大致呈反比例的关系，随着气隙厚度的不断增大，装置的GOR不断减小；产水率和气隙厚度大致呈反比例的关系，随着气隙厚度的增加，产水率不停的下降。冷流进口温度的增大使冷热流端差减小，但使装置的产水率减小，GOR增大；热流进口温度的增大使冷热流端差增大，也使装置产水率增大，GOR增大。通过对气隙蒸馏装置的仿真模拟以及后期对数据进行分析。得出了相关优化措施：该装置的气隙高度应稍高一点并且气隙厚度应尽可能的小一点，并在一定范围内适当的提高冷热流进口温度。关键词：气息扩散；蒸馏；模拟仿真；温度绪论1.1研究背景和意义水资源短缺已经成为制约社会经济发展的核心问题，山西十年九旱，是一个严重缺水省份。山西全省水资源总量142亿立方米，人均占有量381立方米。只有全国平水平均的五分之一，世界平均水平的二十五分之一。另外，目前山西省共有盐碱地261800hm2,占平川总土地面积的9.9%。若能采用低品位热能来将省内的盐碱水进行蒸馏淡化处理，便能使民众就地缓解缺水问题。图1-1山西省降雨量远远赶不上全国平均水平，在没有降雨的季节里，干旱似乎已经习以为常。在很大一部分地区，人民还是靠农田谋生，缺水对他们的打击无疑来说是致命性打击。山西省还有严重的水污染问题，重金属工业废水以及生活垃圾废水污染远比我们想像的严重，所以新的蒸馏技术显得愈发重要。蒸馏技术被广泛应用于各大行业。传统蒸馏方式分为两大类：热蒸馏(TD)和膜蒸馏(MD)，热蒸馏虽应用广泛，能耗低，效率高，但其制作工艺复杂，成本高；膜蒸馏（MD）是一种新兴的分离技术，传统上是通过常规分离工艺（例如蒸馏或反渗透）完成的。自从1960年代末出现和1980年代初随着膜工程的发展而发展起来，MD宣称它是一种经济有效的分离方法，可以利用低品位废物和/或替代能源，例如太阳能和可再生能源。地热能。不幸的是，从商业角度来看，医学博士仅获得很少的认可，并且尚未在工业中实施。主要障碍包括MD膜和组件的设计，膜的湿润性，低渗透液流速和通量衰减以及不确定的能源和经济成本；膜蒸馏（MD）是一种在较低压力下运行并能承受高盐度进料流的热驱动膜技术，已显示出作为脱盐和水净化手段的潜力，膜蒸馏结构简单，操作方便，但其膜传质通量低，传热传质阻力大，还有蒸馏热浪费。故此，我们迫切的需要一种安装简单、能耗低、效率高的一种新型的蒸馏技术：气隙蒸馏，其综合了两种传统技术的优点，不仅能耗低，而且其工作在常压下，部件结构简单，可拆卸，成本较低，是一种非常先进的蒸馏技术。全世界对淡水的需求需要越来越多的植物来处理非常规水源。在过去的几十年里，海水已成为许多干旱地区重要的淡水来源。传统的海水淡化工艺[反渗透(RO)、多级闪蒸(MSF)、多效蒸馏(MED)、电渗析(ED)]已经发展到可靠和成熟的过程。BartVanderBruggen为了降低成本和更环保的操作而改进工艺将替代能源（风能，太阳能，核能）用于反渗透或蒸馏过程，以及不同的脱盐过程对环境的影响；在海水淡化中实施混合工艺；与化学预处理相比，通过压力驱动的膜工艺（微滤、超滤和纳滤）对海水淡化厂进行预处理；新材料防止蒸馏过程中的腐蚀；以及防止反渗透装置结垢。这些改进有助于提高海水淡化过程的成本效益，并确保淡水储量有限的地区长期可持续地生产饮用水。1.2题目研究方案和主要内容首先，阅读相关文献，了解气隙蒸馏技术的相关知识，进行数学模型的假设与建立，然后根据模型分析传热关系式，将相关理论传热关系式导出来；建立气隙蒸馏的传热传质数值模拟程序框图，根据框图通过MATLAB软件编写装置数学模型的程序。依照实验数据对所构建的理论模型进行验证和修改。最后理论分析装置相关性能随装置结构尺寸和工况参数的变化情况，从中找出优化装置结构和性能的方法。程序框图配合公式使用，可以迅速建立模型，进而进行相关计算。A.M.AlklaibiADDINCSL_CITATION{"citationItems":[{"id":"ITEM-1","itemData":{"DOI":"10.1016/j.memsci.2006.05.040","ISSN":"03767388","abstract":"Expressionsforthemasstransferresistancesofallthephysicaldomainscomposingtheair-gapmembranedistillation(AGMD)anddirectcontactmembranedistillation(DCMD)processesaredevelopedandtheirabsoluteandrelativeeffectsareevaluatedtoimprovetheprocessunderstandingandidentifypromisingwaysforitsimprovement.Theresistancesarecomputedbasedontheauthors'two-dimensionalconjugatemodelinwhichasimultaneousnumericalsolutionofthemomentum,energyanddiffusionequationsofthefeedandcoldsolutionshavebeencarriedout,andtheresultsofwhichwerevalidatedincomparisonwithavailableexperimentalresults.Someofthemainconclusionsarethat:(1)theuseandexaminationofprocessdomainmasstransferresistancesisindeedaneffectivemethodforunderstandingtheprocessandidentifyingwaystoimproveit,(2)theair/vaporgapdominatesthemasstransferresistancesoftheAGMDdomains,andwhileincreasingtheair/vaporgapwidthreducestheparasiticheattransferbyconduction,increasingthewidthbeyond2mmhasthusnotimprovedtheprocessthermalefficiency,(3)thehotsolutioninlettemperatureandtheairgapwidthhavebyfarthestrongesteffectonthedomainmasstransferresistance,mainlyasaconsequenceoftheireffectontheair/vaporgapmasstransferresistance,(4)theinletvelocitiesofthehotandcoldsolutionshaveasmalleffectinAGMD,wheretheeffectofthehotsolutionvelocityisthehigherone,(5)theconcentrationofthesolutionhasaslighteffectontheprocess,(6)thematerialusedforthemembraneshouldhaveasmallthermalconductivityforamoreefficientMDprocessand(7)effortstominimizethemasstransferresistanceofthecoldsolutionwillhavearelativelysmalleffectonthepermeateflux.©2006ElsevierB.V.Allrightsreserved.","author":[{"dropping-particle":"","family":"Alklaibi","given":"A.M.","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Lior","given":"Noam","non-dropping-particle":"","parse-names":false,"suffix":""}],"container-title":"JournalofMembraneScience","id":"ITEM-1","issue":"1-2","issued":{"date-parts":[["2006"]]},"page":"362-369","title":"Heatandmasstransferresistanceanalysisofmembranedistillation","type":"article-journal","volume":"282"},"uris":["/documents/?uuid=b468ce5b-bfd0-42b5-b79f-2bd013e6c965"]}],"mendeley":{"formattedCitation":"^[1]","plainTextFormattedCitation":"[1]","previouslyFormattedCitation":"^[1]"},"properties":{"noteIndex":0},"schema":"/citation-style-language/schema/raw/master/csl-citation.json"}[1]等将气隙膜蒸馏过程建模为二维共轭问题，对进料和冷解的动量方程、能量方程和扩散方程进行了数值求解。并与现有实验结果进行了对比验证。得出了主要结论是:(1)空气/蒸气间隙在减少过程中寄生热损失方面起主要作用;(2)间隙宽度有重要作用:(3)增加热液入口温度对渗透通量有重要影响，同时也能提高热效率。而降低冷却液温度有较小影响通量增加,甚至略微降低了效率,(4)给水盐浓度对渗透通量的影响非常小,热效率,(5)的入口速度冷热解决方案影响相对较小,(6)降低膜材料的导热系数，在一定程度上提高了工艺热效率，渗透通量更强。U.Dehesa-CarrascoADDINCSL_CITATION{"citationItems":[{"id":"ITEM-1","itemData":{"DOI":"10.1016/j.desal.2013.07.014","ISSN":"00119164","abstract":"Membranedistillationisaseparationprocessthatinvolvestransferofheatandvaporthroughaporoushydrophobicmembrane.Itcanbeemployedforthermaldesalinationofwaterbylowgradeheatobtained,forinstance,fromlowtemperaturesolarcollectors.Anexperimentalandtheoreticalstudyofanairgapmembranedistillationunitispresented.Thisunitwasbuiltfromaninsulatingmaterialtoreducelosses,andhasaplaneparallelgeometry.Temperaturesaremeasuredatdifferentpointsintheunit,aswellasflowratesanddistillateproduction,toevaluatethedifferententhalpyflows.Inparticular,theinternaltemperaturessurroundingtheairgap,namelythemembraneandcoolingplatetemperatures,aremeasured.Fromthesetemperaturesthediffusioncoefficientforvaporintheairgapisevaluated.Experimentsarecarriedoutfordifferentvaluesofsalinesolutiontemperatureandflowrate.Aonedimensionalheatandmasstransfermodelwithnofreeparametersisproposed.Temperaturespredictedbythemodelarecomparedtotheexperimentalresults.Thecorrespondencebetweenmeasuredandpredictedtemperaturesisnearto5%accuracy,althoughthetrendsofthecurvesdiffersomewhat.Possibleimprovementstothemodelarediscussed.©2013ElsevierB.V.","author":[{"dropping-particle":"","family":"Dehesa-Carrasco","given":"U.","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Pérez-Rábago","given":"C.A.","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Arancibia-Bulnes","given":"C.A.","non-dropping-particle":"","parse-names":false,"suffix":""}],"container-title":"Desalination","id":"ITEM-1","issued":{"date-parts":[["2013"]]},"page":"47-54","publisher":"ElsevierB.V.","title":"Experimentalevaluationandmodelingofinternaltemperaturesinanairgapmembranedistillationunit","type":"article-journal","volume":"326"},"uris":["/documents/?uuid=cab5dbca-0014-45b4-982b-099bd3e3fc2e"]}],"mendeley":{"formattedCitation":"^[2]","plainTextFormattedCitation":"[2]","previouslyFormattedCitation":"^[2]"},"properties":{"noteIndex":0},"schema":"/citation-style-language/schema/raw/master/csl-citation.json"}[2]等对气隙膜蒸馏进行了实验和理论建模，他们测量了膜和冷却板的温度，对不同盐溶液的温度值进行了实验，建立了无自由参数模型，发现其与实验结果较吻合。SumitMukhopadhyayADDINCSL_CITATION{"citationItems":[{"id":"ITEM-1","itemData":{"ISBN":"9780735408036","author":[{"dropping-particle":"","family":"Mukhopadhyay","given":"Sumit","non-dropping-particle":"","parse-names":false,"suffix":""}],"id":"ITEM-1","issue":"June2010","issued":{"date-parts":[["2019"]]},"title":"ACoupledMultiphaseFluidFlowAndHeatAndVaporTransportModelForAir-GapMembraneDistillationWaterFluxesinPolymericMembranesforDesalinationviaMembraneDistillationACoupledMultiphaseFluidFlowAndHeatAndVaporTransportModelForAir-","type":"article-journal","volume":"109"},"uris":["/documents/?uuid=0dd34f4c-7800-4bee-af60-a5f2b79dbcd5"]}],"mendeley":{"formattedCitation":"^[3]","plainTextFormattedCitation":"[3]","previouslyFormattedCitation":"^[3]"},"properties":{"noteIndex":0},"schema":"/citation-style-language/schema/raw/master/csl-citation.json"}[3]通过对气隙膜蒸馏的研究，发现蒸汽输运受两侧蒸汽压差的控制，施加相应的压力梯度，气隙膜蒸馏最有效。在对气隙膜蒸馏的建模中，由于方程的耦合与非线性及其他因素，导致建模难以实现，最终他提出来了一个流体流动、传热和传质耦合模型。A.HemmataADDINCSL_CITATION{"citationItems":[{"id":"ITEM-1","itemData":{"DOI":"10.1016/j.mspro.2015.11.132","ISSN":"22118128","abstract":"Inthepastfewyears,applicationofelectrospunnanofiberhasgainedintensiveattentionformembranedistillation(MD)thatexhibitpromisingresults.Inthisstudytheeffectsofthreesaltadditivesincludingcalciumcarbonate(CaCO3),lithiumchloride(LiCl)andcalciumchloride(CaCl2)onthemorphology,hydrophobicity,porosityandpermeationperformanceofpoly(vinylidenefluoride-co-hexafluropropylene)(PVDF-HFP)nanofibermembraneswereinvestigated.Scanningelectronmicroscopy(SEM),geniometer,gravimetricmethodandairgapMD(AGMD)setupwereusedtocharacterizetheresultantPVDF-HFPmembranes.ItwasobservedthatadditionofLiClandCaCl2improvedtheelectrospinabilityofpolymerdopesolutionandchangesthemorphologyoffibersfrombeadedfibertoauniformfiberstructure.AlsothemembranemadefromthedopewithLiClastheadditivesaltpossessedthehighestporosityof%89.ThemembranehydrophobicitywasaffectedlessbyCaCO3ascomparedwithLiClandCaCl2.Thesynthesizedmembranewasappliedindesalinationviaairgapmembranedistillation,inwhichawaterpermeationfluxof13.6,12.2and9.8Lh-1m-2wereobtainedwhenLiCl,CaCl2andCaCO3wasusedastheadditive,respectively.","author":[{"dropping-particle":"","family":"Hemmat","given":"A.","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Ghoreishi","given":"S.M.","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Sabet","given":"J.Karimi","non-dropping-particle":"","parse-names":false,"suffix":""}],"container-title":"ProcediaMaterialsScience","id":"ITEM-1","issue":"LiCl","issued":{"date-parts":[["2015"]]},"page":"370-375","publisher":"ElsevierB.V.","title":"EffectofSaltAdditivesontheFabricationofPoly(vinylidenefluoride-co-hexafluropropylene)(PVDF-HFP)NanofiberMembranesforAirGapMembraneDistillation","type":"article-journal","volume":"11"},"uris":["/documents/?uuid=fb04ff31-b206-44bc-a3fa-b33035b4bfdf"]}],"mendeley":{"formattedCitation":"^[4]","plainTextFormattedCitation":"[4]","previouslyFormattedCitation":"^[4]"},"properties":{"noteIndex":0},"schema":"/c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