蒸發(fā)

Evaporation蒸發(fā)操作的特點及應用

Characteristicsandapplicationsofevaporationoperation蒸發(fā)操作的特點及應用

Characteristicsandapplicationsofevaporationoperation課程導入

Courseguide不飽和

Unsaturated飽和

Saturated蒸發(fā)結晶

Evaporativecrystallization

生產(chǎn)實例

ProductionExamplesKNO3

NaCl多

MoreNaClKNO3

少

LessKNO3

NaCl(食鹽）

NaCl(TableSalt)KNO3NaCl和KNO3混合物溶液

NaClandKNO3Mixturesolution蒸發(fā)操作的特點及應用

Characteristicsandapplicationsofevaporationoperation蒸發(fā)

Evaporation用加熱的方法，將含有不揮發(fā)性溶質的溶液加熱至沸騰狀況。Asolutioncontaininganon-volatilesoluteisheatedtoaboilingstatebyheating.蒸發(fā)操作的特點及應用

Characteristicsandapplicationsofevaporationoperation移除

Remove汽化

Gasification提高

Enhance溶質濃度的單元操作

UnitOperationofSoluteConcentration蒸發(fā)

Evaporation蒸發(fā)操作的特點及應用

Characteristicsandapplicationsofevaporationoperation工業(yè)領域廣泛應用

Widelyusedintheindustrialfield蒸發(fā)操作的特點及應用

Characteristicsandapplicationsofevaporationoperation海水淡化

Seawaterdesalination蒸發(fā)操作在工業(yè)中的應用

Applicationofevaporationoperationinindustry獲得純凈溶劑

Obtainapuresolvent工業(yè)生產(chǎn)中應用蒸發(fā)操作的場合

Occasionsofapplicationofevaporationinindustrialproduction蒸發(fā)操作的特點及應用

Characteristicsandapplicationsofevaporationoperation有機磷農(nóng)藥苯溶液的濃縮脫苯

Benzeneremovalbyconcentrationofbenzenesolutionoforganophosphoruspesticide中藥酒精浸出液的蒸發(fā)

Evaporationofethanol-basedherbalextract濃縮溶液和回收溶液

Concentratedsolutionandrecoveredsolution蒸發(fā)操作的特點及應用

Characteristicsandapplicationsofevaporationoperation蒸發(fā)操作在工業(yè)中的應用

Applicationofevaporationoperationinindustry工業(yè)生產(chǎn)中應用蒸發(fā)操作的場合

Occasionsofapplicationofevaporationinindustrialproduction電解燒堿液

Electrolyticcausticsodasolution食糖水溶液

Sugaraqueoussolution

果汁

Fruitjuice濃縮稀溶液直接制取產(chǎn)品或將濃溶液再處理制取固體產(chǎn)品

Concentratethedilutesolutiontoobtaintheproductdirectlyorreprocesstheconcentratedsolutiontoobtainthesolidproduct蒸發(fā)操作的特點及應用

Characteristicsandapplicationsofevaporationoperation蒸發(fā)操作在工業(yè)中的應用

Applicationofevaporationoperationinindustry工業(yè)生產(chǎn)中應用蒸發(fā)操作的場合

Occasionsofapplicationofevaporationinindustrialproduction化學

Chemical食品

Foodstuffs

制藥

Pharmaceuticals蒸發(fā)操作的特點及應用

Characteristicsandapplicationsofevaporationoperation蒸發(fā)操作在工業(yè)中的應用

Applicationofevaporationoperationinindustry蒸發(fā)操作，即為一個使溶液中的揮發(fā)性溶劑與不揮發(fā)性溶質的分離過程。Evaporationoperationisaprocessofseparatingvolatilesolventsfromnon-volatilesolutesinasolution.分離

Separate取決于

Dependson傳熱過程

heattransferprocess蒸發(fā)操作

Evaporationoperation屬于

Is屬于

Is部分溶液

Partialsolution溶劑汽化速率

Solventvaporizationrate傳熱速率

Heattransferrate傳熱設備

Heattransferequipment蒸發(fā)設備

Evaporationequipment蒸發(fā)操作的特點及應用

Characteristicsandapplicationsofevaporationoperation蒸發(fā)操作的特點

Characteristicsofevaporationoperations溶液沸點升高相同溫度

Theboilingpointofthesolutionincreasesbythesametemperature含不揮發(fā)性溶質

Containsnon-volatilesolutes＜＜溶液濃度越高，影響越顯著

Thehigherthesolutionconcentration,themoresignificanttheeffect純?nèi)軇┱魵鈮?/p>

Puresolventvaporpressure溶液的蒸氣壓

Vaporpressureofsolution溶液的沸點

Boilingpointofsolution純?nèi)軇┓悬c

Boilingpointofpuresolvent蒸發(fā)操作的特點及應用

Characteristicsandapplicationsofevaporationoperation蒸發(fā)操作的特點

Characteristicsofevaporationoperations物料濃縮過程中，溶質或雜質常在加熱表面沉積、析出結晶而形成垢層，影響傳熱。Duringthematerialconcentrationprocess,solutesorimpuritiesoftendepositandcrystallizeontheheatingsurfacetoformascalelayer,whichaffectsheattransfer.熱敏性物料汽化（蒸發(fā)器）

Vaporizationofheatsensitivematerials(evaporator)高溫停留時間過長

Hightemperatureresidencetimeistoolong熱敏性溶質

Thermosensitivesolute易變質

Perishable腐蝕性

Caustic粘度

Viscosity物料及工藝特性

MaterialandProcessCharacteristics蒸發(fā)操作的特點及應用

Characteristicsandapplicationsofevaporationoperation蒸發(fā)操作的特點

Characteristicsofevaporationoperations蒸發(fā)過程是溶劑汽化過程，由于溶劑汽化潛熱很大，蒸發(fā)過程是一個大能耗單元操作。Theevaporationprocessisasolventvaporizationprocess.Becauseofthelargelatentheatofsolventvaporization,theevaporationprocessisaunitoperationwithlargeenergyconsumption.耗能大

Largeenergyconsumption節(jié)能是蒸發(fā)操作重要考慮問題

Energysavingisanimportantconsiderationinevaporationoperation能量回收

Energyrecovery蒸發(fā)操作的特點及應用

Characteristicsandapplicationsofevaporationoperation蒸發(fā)操作的特點

Characteristicsofevaporationoperations自然蒸發(fā)：溶液在低于沸點溫度下蒸發(fā)Naturalevaporation:evaporationofasolutionatatemperaturebelowtheboilingpoint.以蒸發(fā)方式劃分

Dividedbyevaporation溶液表面汽化

Solutionsurfacevaporization溶劑汽化速率低

Lowsolventvaporizationrate自然蒸發(fā)海水曬鹽

?Solarevaporationsalt-making蒸發(fā)操作的特點及應用

Characteristicsandapplicationsofevaporationoperation蒸發(fā)操作的分類Classificationofevaporationoperations沸騰蒸發(fā)：溶液加熱至沸點蒸發(fā)Boilingevaporation:thesolutionevaporateswhenheatedtoboilingpoint.蒸發(fā)操作的特點及應用

Characteristicsandapplicationsofevaporationoperation蒸發(fā)操作的分類Classificationofevaporationoperations自然蒸發(fā)：溶液在低于沸點溫度下蒸發(fā)Naturalevaporation:evaporationofasolutionatatemperaturebelowtheboilingpoint.以蒸發(fā)方式劃分

Dividedbyevaporation直接熱源加熱：燃料與空氣混合，使高溫火焰經(jīng)噴嘴，直接噴入被蒸發(fā)的溶液中來加熱溶液、使溶劑汽化。Directheatsourceheating:Thefuelismixedwithair,andthehigh-temperatureflameisdirectlysprayedintotheevaporatedsolutionthroughthenozzletoheatthesolutionandvaporizethesolvent.燃料

Fuel

空氣

Air

產(chǎn)生

Producte高溫火焰

Hightemperatureflame以加熱方式劃分

Dividedbyheating蒸發(fā)操作的特點及應用

Characteristicsandapplicationsofevaporationoperation蒸發(fā)操作的分類Classificationofevaporationoperations間接熱源加熱：容器間壁傳給被蒸發(fā)的溶液。Indirectheatsourceheating:Thepartitionwallofthecontaineristransferredtotheevaporatedsolution.蒸發(fā)操作的特點及應用

Characteristicsandapplicationsofevaporationoperation蒸發(fā)操作的分類Classificationofevaporationoperations直接熱源加熱：燃料與空氣混合，使高溫火焰經(jīng)噴嘴，直接噴入被蒸發(fā)的溶液中來加熱溶液、使溶劑汽化。Directheatsourceheating:Thefuelismixedwithair,andthehigh-temperatureflameisdirectlysprayedintotheevaporatedsolutionthroughthenozzletoheatthesolutionandvaporizethesolvent.以加熱方式劃分

Dividedbyheating抗生素溶液

Antibioticsolution果汁

Fruitjuice減壓：對于熱敏性物料，應在減壓下進行。Pressurereduction:Forheatsensitivematerials,itshouldbecarriedoutunderreducedpressure.以操作壓力劃分

Divisionbyoperatingpressure分為常壓、加壓和減壓（真空）蒸發(fā)操作壓。Itisdividedintoatmospheric,pressurizedand?reduced(vacuum)evaporationoperatingpressure.蒸發(fā)操作的特點及應用

Characteristicsandapplicationsofevaporationoperation蒸發(fā)操作的分類Classificationofevaporationoperations加壓：對于高粘度物料，應在加壓下進行。Pressurization:Forhighviscositymaterials,itshouldbecarriedoutunderpressurizedpressure.熔鹽

Moltensalt蒸發(fā)操作的特點及應用

Characteristicsandapplicationsofevaporationoperation蒸發(fā)操作的分類Classificationofevaporationoperations減壓：對于熱敏性物料，應在減壓下進行。Pressurereduction:Forheatsensitivematerials,itshouldbecarriedoutunderreducedpressure.以操作壓力劃分

Divisionbyoperatingpressure分為常壓、加壓和減壓（真空）蒸發(fā)操作壓。Itisdividedintoatmospheric,pressurizedand?reduced(vacuum)evaporationoperatingpressure.單效蒸發(fā)：蒸發(fā)產(chǎn)生的二次蒸汽直接冷凝不再利用。Single-effectevaporation:thesecondarysteamgeneratedbyevaporationisdirectlycondensedandnolongerused.以效數(shù)劃分

Dividedbyeffectnumber多效蒸發(fā)：將二次蒸汽作為下一效加熱蒸汽，并將多個蒸發(fā)器串聯(lián)。Multi-effectevaporation:Thesecondarysteamisusedasthenexteffectheatingsteam,andmultipleevaporatorsareconnectedinseries.蒸發(fā)操作的特點及應用

Characteristicsandapplicationsofevaporationoperation蒸發(fā)操作的分類Classificationofevaporationoperations蒸發(fā)需要用到哪些設備呢？

Whatequipmentisneededforevaporation?蒸發(fā)操作的特點及應用

Characteristicsandapplicationsofevaporationoperation

流動（或循環(huán)）管道

Flow(orcirculation)pipe

加熱室（器）

Heatingchamber

分離室（器）

Separationchamber蒸發(fā)操作的結構形式

Structuralformofevaporationoperation蒸發(fā)操作的特點及應用

Characteristicsandapplicationsofevaporationoperation根據(jù)溶液在加熱室內(nèi)的流動情況，蒸發(fā)器可分為循環(huán)型和單程型兩類。

Accordingtotheflowofthesolutionintheheatingchamber,evaporatorscanbedividedintotwotypes:circulatingtypeand

single-passtype.蒸發(fā)設備

Evaporationequipment循環(huán)蒸發(fā)

Circulatingevaporation單程蒸發(fā)

Single-passevaporation自然循環(huán)型蒸發(fā)器

Naturalcirculationevaporator強制循環(huán)發(fā)生器

Forcedcirculationevaporator單程型蒸發(fā)器

Single-passevaporator蒸發(fā)操作的特點及應用

Characteristicsandapplicationsofevaporationoperation課程小結

Coursesummary蒸發(fā)

Evaporation概念

Concept工業(yè)應用和設備

Industrialapplicationsandequipment蒸發(fā)操作的特點及應用

Characteristicsandapplicationsofevaporationoperation課程小結

Coursesummary不飽和溶液

Unsaturatedsolution飽和溶液Saturatedsolution蒸發(fā)

Evaporate

工業(yè)中廣泛應用

Widelyusedinindustry

蒸發(fā)操作的特點及應用

Characteristicsandapplicationsofevaporationoperation思考題

Thinkingquestions你還知道蒸發(fā)其它工業(yè)上有什么應用？Whatotherindustrialapplicationsdoyouknowofevaporation?課程導入

Courseguide

單效蒸發(fā)

Single-effectevaporation一次蒸發(fā)

First-effectevaporation多效蒸發(fā)

Multi-effectevaporation課程導入

Courseguide

雙效蒸發(fā)Double-effectevaporation

將第一效蒸發(fā)器汽化的二次蒸汽，作為熱源通入第二效蒸發(fā)器的加熱室作加熱用。

Thesecondarysteamvaporizedbythefirst-effectevaporatorispassedintotheheatingchamberofthesecond-effectevaporatorasaheatsourceforheating.

多效蒸發(fā)

Multi-effectevaporation課程導入

Courseguide

多效蒸發(fā)Multi-effectevaporation

將第二效的二次蒸汽通入第三效加熱室作為熱源，并依次進行多個串接。

Thesecondarysteamofthesecondeffectisintroducedintotheheatingchamberofthethirdeffectasaheatsource,andapluralityofsteamsaresequentiallyconnectedinseries.多效蒸發(fā)

Multi-effectevaporation將前效的二次蒸汽作為下一效加熱蒸汽的串聯(lián)蒸發(fā)操作。Multi-effectevaporationisaseriesevaporationoperationinwhichthesecondarysteamofthepreviouseffectisusedastheheatingsteamofthenexteffect.各效的操作壓力、相應的加熱蒸汽溫度與溶液沸點依次降低。Theoperatingpressureofeacheffect,thecorrespondingheatingsteamtemperatureandtheboilingpointofthesolutiondecreaseinturn.多效蒸發(fā)

Multi-effectevaporation萃取又稱液液萃取，是指兩個完全不互溶或部分互溶的液相接觸后，一個液相中的溶質經(jīng)過物理或化學作用另一個液相，或在兩相中重新分配的過程。

Extraction,alsoknownasliquid-liquidextraction,referstotheprocessinwhich,aftertwocompletelyimmiscibleorpartiallymiscibleliquidphasescomeintocontactwitheachother,thesoluteinoneliquidphasetransferstotheotherliquidphaseunderphysicalorchemicalinteractions,orthesolutegetsredistributedinthetwophases.

多效蒸發(fā)的目的

Purposeofmulti-effectevaporation減少加熱蒸汽的用量。具體方法是將前一效的二次蒸汽作為一效的加熱蒸汽，以節(jié)省蒸汽用量。Reducetheamountofheatingsteamused.Thespecificmethodistousethesecondarysteamoftheformereffectastheheatingsteamofthefirsteffecttosavethesteamconsumption.

多效蒸發(fā)

Multi-effectevaporation多效蒸發(fā)的操作流程Operationprocedureofmulti-effectevaporation效數(shù)限制Effectnumberlimit節(jié)能措施Energy-savingmeasures多效蒸發(fā)

Multi-effectevaporation多效蒸發(fā)

Multi-effectevaporation萃取又稱液液萃取，是指兩個完全不互溶或部分互溶的液相接觸后，一個液相中的溶質經(jīng)過物理或化學作用另一個液相，或在兩相中重新分配的過程。

Extraction,alsoknownasliquid-liquidextraction,referstotheprocessinwhich,aftertwocompletelyimmiscibleorpartiallymiscibleliquidphasescomeintocontactwitheachother,thesoluteinoneliquidphasetransferstotheotherliquidphaseunderphysicalorchemicalinteractions,orthesolutegetsredistributedinthetwophases.

多效蒸發(fā)流程

Multi-effectevaporationprocess

為了合理利用有效溫差，并根據(jù)處理物料的性質，通常多效蒸發(fā)有下列三種操作流程：Inordertorationallyutilizetheeffectivetemperaturedifferenceandaccordingtothenatureoftheprocessedmaterials,multi-effectevaporationusuallyhasthefollowingthreeoperatingprocesses:并流加料Cocurrentfeeding

逆流加熱Counter-currentheating

平流加料Advectioncharging

多效蒸發(fā)

Multi-effectevaporation萃取又稱液液萃取，是指兩個完全不互溶或部分互溶的液相接觸后，一個液相中的溶質經(jīng)過物理或化學作用另一個液相，或在兩相中重新分配的過程。

Extraction,alsoknownasliquid-liquidextraction,referstotheprocessinwhich,aftertwocompletelyimmiscibleorpartiallymiscibleliquidphasescomeintocontactwitheachother,thesoluteinoneliquidphasetransferstotheotherliquidphaseunderphysicalorchemicalinteractions,orthesolutegetsredistributedinthetwophases.

料液可藉相鄰二效的壓強差自動流入后一效，而不需用泵輸送，由于前一效的沸點比后一效的高，因此當物料進入后一效時，會產(chǎn)生自蒸發(fā)，這可多蒸出一部分水汽。

Thematerialliquidcanautomaticallyflowintothelattereffectbythepressuredifferencebetweenthetwoadjacenteffectswithoutpumpingit.Sincetheboilingpointoftheformereffectishigherthanthatofthelattereffect,whenthematerialentersthelattereffect,itwillproduceself-evaporation,whichcanevaporatemorewatervapor.1

2

3

原料液

Rawmaterialliquid加熱蒸汽

Heatingsteam去冷凝劑

Decondensingagent完成液

Finishedliquid優(yōu)點

Advantages較簡便，易于穩(wěn)定

Simpleandeasytostabilize并流加料

Cocurrentfeeding多效蒸發(fā)

Multi-effectevaporation多效蒸發(fā)流程

Multi-effectevaporationprocess萃取又稱液液萃取，是指兩個完全不互溶或部分互溶的液相接觸后，一個液相中的溶質經(jīng)過物理或化學作用另一個液相，或在兩相中重新分配的過程。

Extraction,alsoknownasliquid-liquidextraction,referstotheprocessinwhich,aftertwocompletelyimmiscibleorpartiallymiscibleliquidphasescomeintocontactwitheachother,thesoluteinoneliquidphasetransferstotheotherliquidphaseunderphysicalorchemicalinteractions,orthesolutegetsredistributedinthetwophases.

傳熱系數(shù)會下降。因為后序各效的濃度會逐漸增高，但沸點反而逐漸降低，導致溶液粘度逐漸增大。

Theheattransfercoefficientwilldecrease.Becausetheconcentrationofsubsequenteffectswillgraduallyincrease,buttheboilingpointwillgraduallydecrease,resultinginagradualincreaseintheviscosityofthesolution.缺點

Disadvantages1效

1-effect3效

3-effect2效

2-effect加熱蒸汽

Heatingsteam料液

Feedliquid冷凝水

Condensate冷凝水

Condensate冷凝水

Condensate二次蒸發(fā)

Secondaryevaporation完成液

Finishedliquid多效蒸發(fā)流程

Multi-effectevaporationprocess并流加料

Cocurrentfeeding多效蒸發(fā)

Multi-effectevaporation萃取又稱液液萃取，是指兩個完全不互溶或部分互溶的液相接觸后，一個液相中的溶質經(jīng)過物理或化學作用另一個液相，或在兩相中重新分配的過程。

Extraction,alsoknownasliquid-liquidextraction,referstotheprocessinwhich,aftertwocompletelyimmiscibleorpartiallymiscibleliquidphasescomeintocontactwitheachother,thesoluteinoneliquidphasetransferstotheotherliquidphaseunderphysicalorchemicalinteractions,orthesolutegetsredistributedinthetwophases.

料液輸送必須用泵，另外，進料也沒有自蒸發(fā)。

Thefeedliquidmustbetransportedbyapump,andinaddition,thefeedisnotself-vaporized.缺點

Disadvantages

逆流加料工藝流程示意圖

Schematicdiagramofcountercurrentfeedingprocessflow

各效濃度和溫度對溶液的粘度的影響大致相抵消，各效的傳熱條件大致相同，即傳熱系數(shù)大致相同。

Theeffectsofconcentrationandtemperatureofeacheffectontheviscosityofthesolutionareroughlyoffset,andtheheattransferconditionsofeacheffectareroughlythesame,thatis,theheattransfercoefficientisroughlythesame.優(yōu)點

Advantages1

2

3

加熱蒸汽

Heatingsteam去冷凝劑

Decondensingagent完成液

Finishedliquid原料液

Rawmaterialliquid逆流加熱

Counter-currentheating多效蒸發(fā)

Multi-effectevaporation多效蒸發(fā)流程

Multi-effectevaporationprocess萃取又稱液液萃取，是指兩個完全不互溶或部分互溶的液相接觸后，一個液相中的溶質經(jīng)過物理或化學作用另一個液相，或在兩相中重新分配的過程。

Extraction,alsoknownasliquid-liquidextraction,referstotheprocessinwhich,aftertwocompletelyimmiscibleorpartiallymiscibleliquidphasescomeintocontactwitheachother,thesoluteinoneliquidphasetransferstotheotherliquidphaseunderphysicalorchemicalinteractions,orthesolutegetsredistributedinthetwophases.

溶液粘度隨溫度變化較大的場合。Occasionswherethesolutionviscositychangesgreatlywithtemperature.逆流加熱使用場景

Counter-currentheatingusagescenarios逆流加熱

Counter-currentheating多效蒸發(fā)

Multi-effectevaporation多效蒸發(fā)流程

Multi-effectevaporationprocess萃取又稱液液萃取，是指兩個完全不互溶或部分互溶的液相接觸后，一個液相中的溶質經(jīng)過物理或化學作用另一個液相，或在兩相中重新分配的過程。

Extraction,alsoknownasliquid-liquidextraction,referstotheprocessinwhich,aftertwocompletelyimmiscibleorpartiallymiscibleliquidphasescomeintocontactwitheachother,thesoluteinoneliquidphasetransferstotheotherliquidphaseunderphysicalorchemicalinteractions,orthesolutegetsredistributedinthetwophases.

處理易結晶物料，例如食鹽水溶液等的蒸發(fā)。Evaporationofmaterialseasytocrystallize,suchasaqueoussaltsolution.適用情況

Applicableconditions

蒸汽的走向與并流相同，但原料液和完成液則分別從各效加入和排出。

Thedirectionofthesteamisthesameasthatoftheco-current,buttherawmaterialliquidandthefinishedliquidareaddedanddischargedfromeacheffect,respectively.特點

Characteristics平流加料

Advectioncharging多效蒸發(fā)

Multi-effectevaporation多效蒸發(fā)流程

Multi-effectevaporationprocess多效蒸發(fā)數(shù)的限制Effectnumberlimitationofmulti-effectevaporation

蒸汽會因多種原因而無法進行無限制地蒸發(fā)，即效數(shù)限制。

Steamcannotevaporatewithoutrestrictionforanumberofreasons,thatis,efficiencylimitation.多效蒸發(fā)

Multi-effectevaporation萃取又稱液液萃取，是指兩個完全不互溶或部分互溶的液相接觸后，一個液相中的溶質經(jīng)過物理或化學作用另一個液相，或在兩相中重新分配的過程。

Extraction,alsoknownasliquid-liquidextraction,referstotheprocessinwhich,aftertwocompletelyimmiscibleorpartiallymiscibleliquidphasescomeintocontactwitheachother,thesoluteinoneliquidphasetransferstotheotherliquidphaseunderphysicalorchemicalinteractions,orthesolutegetsredistributedinthetwophases.

單效蒸發(fā)和多效蒸發(fā)過程中均存在溫度差損失Thereis

temperaturedifferenceloss

inbothsingle-effectevaporationandmulti-effectevaporation加熱蒸汽壓力相同

Sameheatingsteampressure

多效蒸發(fā)的溫度差損失>單效蒸發(fā)的溫度差損失

Temperaturedifferencelossofmulti-effectevaporation>temperaturedifferencelossofsingle-effectevaporation

溶液的溫度差損失

Temperaturedifferencelossofsolution效數(shù)越多，溫度差損失將越大

Thegreatertheeffectnumber,thegreaterthetemperaturedifferencelosswillbe單效蒸發(fā)操作條件

Single-effectevaporationoperatingconditions多效蒸發(fā)操作條件

Multi-effectevaporationoperatingconditions多效蒸發(fā)

Multi-effectevaporation多效蒸發(fā)效數(shù)的限制

Effectnumberlimitationofmulti-effectevaporation多效蒸發(fā)效數(shù)的限制

Effectnumberlimitationofmulti-effectevaporation效數(shù)的增加，單位蒸汽的消耗量減少

Withtheincreaseofefficiency,theconsumptionperunitsteamdecreases操作費用降低

Decreaseofoperatingexpenses有效溫度差會減少（即溫度差損失增大）

Theeffectivetemperaturedifferencewilldecrease(i.e.thetemperaturedifferencelosswillincrease)設備投資費用增大

Increaseinequipmentinvestmentcosts多效蒸發(fā)效數(shù)的限制

Effectnumberlimitationofmulti-effectevaporation多效蒸發(fā)

Multi-effectevaporation必須合理選取蒸發(fā)效數(shù)，使操作費和設備費之和為最少。Theevaporationefficiencymustbereasonablyselectedtominimizethesumofoperationcostandequipmentcost.

效數(shù)

Effectnumber單效

Single-effect雙效

Double-effect三效

Triple-effect四效

Four-effects五效

Five-effects（D/W）min的理論值

Theoreticalvalueof(D/W)min

1

0.5

0.33

0.25

0.2

（D/W）min的理論值

Theoreticalvalueof(D/W)min1.1

0.57

0.4

0.3

0.27

不同效數(shù)蒸發(fā)的單位蒸汽消耗量

Unitsteamconsumptionofevaporationwithdifferenteffect

多效蒸發(fā)效數(shù)的限制

Effectnumberlimitationofmulti-effectevaporation多效蒸發(fā)

Multi-effectevaporation多效蒸發(fā)效數(shù)的限制

Effectnumberlimitationofmulti-effectevaporation節(jié)能降耗永遠是生產(chǎn)企業(yè)的主題Energysavingandconsumptionreduction

isal