課程導(dǎo)入

Courseguide

單效蒸發(fā)

Single-effectevaporation一次蒸發(fā)

First-effectevaporation多效蒸發(fā)

Multi-effectevaporation林忠

Lin

Zhong

主講教師

Lecturer課程導(dǎo)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(dǎo)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(jìn)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(yīng)的加熱蒸汽溫度與溶液沸點(diǎn)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(zhì)經(jīng)過物理或化學(xué)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(zhì)經(jīng)過物理或化學(xué)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(zhì)，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(zhì)經(jīng)過物理或化學(xué)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(qiáng)差自動流入后一效，而不需用泵輸送，由于前一效的沸點(diǎn)比后一效的高，因此當(dāng)物料進(jìn)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(diǎn)

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(zhì)經(jīng)過物理或化學(xué)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?yàn)楹笮蚋餍У臐舛葧饾u增高，但沸點(diǎn)反而逐漸降低，導(dǎo)致溶液粘度逐漸增大。

Theheattransfercoefficientwilldecrease.Becausetheconcentrationofsubsequenteffectswillgraduallyincrease,buttheboilingpointwillgraduallydecrease,resultinginagradualincreaseintheviscosityofthesolution.缺點(diǎn)

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(zhì)經(jīng)過物理或化學(xué)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(jìn)料也沒有自蒸發(fā)。

Thefeedliquidmustbetransportedbyapump,andinaddition,thefeedisnotself-vaporized.缺點(diǎn)

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(diǎn)

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(zhì)經(jīng)過物理或化學(xué)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(zhì)經(jīng)過物理或化學(xué)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(jié)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(diǎn)

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(jìn)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(zhì)經(jīng)過物理或化學(xué)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(fèi)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(shè)備投資費(fèi)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(fèi)和設(shè)備費(fèi)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(yuǎn)是生產(chǎn)企業(yè)的主題Energysavingandconsumptionreduction

isalwaysthethemeofourproductionenterprises多效蒸發(fā)

Multi-effectevaporation

二次蒸汽從蒸發(fā)室出來，帶有大量的熱，可利用這部分潛熱作為其它加熱設(shè)備的熱源，即廢熱利用又可節(jié)約大量的冷卻水。

Thesecondarysteamcomesoutoftheevaporationchamberwithalargeamountofheat.Thispartoflatentheatcanbeusedastheheatsourceofotherheatingequipment,whichcansavealargeamountofcoolingwaterbyutilizingwasteheat.二次蒸汽的利用

Utilizationofsecondarysteam蒸發(fā)過程的節(jié)能措施

Energy-savingmeasuresintheevaporationprocess多效蒸發(fā)

Multi-effectevaporation特點(diǎn)

Characteristics溫度高而且潔凈Hightemperatureandclean用途

Uses預(yù)熱原料Preheatrawmaterials加熱其它物料Heatothermaterials冷凝水的利用

Utilizationofcondensate蒸發(fā)過程的節(jié)能措施

Energy-savingmeasuresintheevaporationprocess多效蒸發(fā)

Multi-effectevaporation

將蒸發(fā)室排出的二次蒸汽進(jìn)入壓縮機(jī)內(nèi)提高壓力，使其飽和溫度超過溶液的沸點(diǎn)，再送回蒸發(fā)室作加熱室的加熱蒸汽。

Thesecondarysteamdischar