基于AspenPlus的甲醇與水篩板板精餾塔設計書

基于AspenPlus的甲醇與

水篩板板精餾塔設計書第一章流程確定和說明塔板類型1）精餾塔的塔板類型有三種：泡罩塔板，篩孔塔板，浮閥塔板。篩板塔板具有結構簡單，制造方便，造價低等優(yōu)點；2）本設計采用篩板精餾塔；3）加料方式本精餾塔加料選擇泵接加料，結構簡單，安裝方便，而且可以引入自動控制系統(tǒng)來實時調節(jié)流量及流速。進料狀況本精餾塔選擇泡點進料，常溫原料經(jīng)換熱后進料。塔頂冷凝方式甲醇與水不反應，且容易冷凝，故本精餾塔塔頂選擇全凝器，可用水冷凝。塔釜加熱方式塔釜使用200℃的飽和蒸汽間接加熱?；亓鞅仍撐锵祵僖追蛛x物系，最小回流比較小，故操作回流比取最小回流比的1.2?2倍，本設計規(guī)定回流比取最小回流比的1.5倍?；亓鞣绞奖驹O計處理量大，所需塔板數(shù)多，塔較高，回流冷凝器不適宜塔頂安裝，故采用強制回流。操作壓力甲醇-水在常壓下相對揮發(fā)度較大，因此在常壓下也比較容易分離，故本設計采用常壓精餾。1.8工藝流程確定如圖1是甲醇-水工藝流程草圖：圖1.甲醇-水分離工藝流程第二章塔板工藝設計2.1精餾塔全塔物料衡算2.1.1設計要求及條件表1.設計要求及條件處理量（萬噸/年）Xd（質量分數(shù)，％）Xf（質量分數(shù)，％） Xw（質量分數(shù)，％） R/Rmin4.5 98.5 45 0.3 1.52.1.2原料液級塔頂、塔底產(chǎn)品的摩爾分率已知：甲醇的摩爾質量MA=32.04Kg/Kmol,水的摩爾質量MB=18.02Kg/Kmol。原料液組成可（摩爾分數(shù)，下同）=0.3151=0.31510.45/32.04+0.55/18.02塔頂組成二0.9736二0.97360.985/32.04+0.015/18.02塔底組成=0.001689=0.0016890.003/32.04+0.997/18.022.1.3原料液及塔頂、塔底產(chǎn)品的平均摩爾質量M=0.3151x32.04+(1-0.315Dx18.02=22.44kg/km)lFM=0.9736x32.04+(1-0.9736)x18.02=31.67kg/kmDlDM=0.0017x32.04+(1-0.0017)x18.02=18.04kg/kmolW2.1.4全塔物料衡算一年以300天，一天以24小時計，計算可得進料流率：4.5x104x103xln.45/32.04+(1-0.45)/18.021f一1Z1300x24F=4.5萬噸/年= 二278.54km)300x24全塔物料衡算式：Fx=Dx+Wx聯(lián)立代入求解：D=89.82kmol/h,W=188.72kmol/h2.1.5塔頂回收率甲醇回收率：Dx-D=0.9964甲醇回收率：Dx-D=0.9964FxF水回收率：D(1—x)

f(i-xD)=0.01242.2利用AspenPlus模擬進行塔工藝計算過程2.2.1常壓下甲醇-水氣液平衡組成與溫度關系利用aspen利用aspen繪制的甲醇-水體系的T-x-y相圖，如圖2。依據(jù)進料摩爾分數(shù)，求得體系2.2.2甲醇-水精餾塔的簡捷計算DSTWU簡捷塔模塊的任務是從反應混合物中從塔頂分離甲醇。首先用簡捷計算方法求出完成指定分離任務需要的最小回流比、最小理論塔板數(shù)和進料位置，為嚴格計算提供初值。

圖3.甲醇-水分離篩板精餾塔DSTWU簡捷塔模塊點擊ModelLibrary橫條上的“Columns"。選擇“DSTWU”模塊，拖放到工藝流程圖窗口，用物流線與反應器連接，并用物流線連接精餾塔的兩出口。為便于閱讀，對精餾塔的兩出口物流更改名稱。點擊“Next”按鈕，進行化學組分的定義。點擊“ Find”，在彈出的對話框的“Componentnameor”欄中填入組分名稱“CH4O”然后點擊“Findnow”然后點擊“Add”。以此類推，定義甲醇、水組分。DefinecomponentsComponentIDTypeComponentnameFormulaCH40ConventionalMETHANOLCH40H20ConventionalWMERH20卜點擊“Next”按鈕，選擇熱力學方法。在Global頁的“Propertymethod”下拉框中選上“NRTL-RK”。^/Global!FlowsheetSecticms1Referenced入對應欄目中。Propertymethods&madelsPrate??t^pe;Basemethod:[allNRTL-RKHenrpcomponerts:點擊“Next”按鈕，點擊“OKPropertymethad:|NRTL-RKPropertymethods&madelsPrate??t^pe;Basemethod:[allNRTL-RKHenrpcomponerts:點擊“Next”按鈕，點擊“OKPropertymethad:|NRTL-RKI-Modifypropertymodels*Pantingcoriection「Useliq.referente-stateerithalpjj進行流股信息的設置，把題目給定的進料物流信息填SpeciFications|FlashOptions1PSD1ComponentAttr.\EOOptionsSubstr&amname:卜MIXED卜［—Statevariables|VaporfractionrI 二J|Pressure二I140|kPa司Totalflow:Mole—Statevariables|VaporfractionrI 二J|Pressure二I140|kPa司Totalflow:Mole▼278.54kmolZhrTSolvent:I 二JCompositicm|Mole-Frac▼|CamponentValueCH400.3151?H200.6849點擊“Next”按鈕，出現(xiàn)精餾塔的簡捷計算設置窗口。填入R/Rmi為1.5,塔頂、底壓力分別是110kPa和130kPa；甲醇和水為輕、重關鍵組分，塔頂甲醇和水的回收率分別為0.9964和0.0124。dSpecificationfCslciilatioriOptiorsCorivergenceKeiJcomponentrecoveriesLightkey:Condenserspecifications岸T口閆condenser「Partialcondenserwithallvapordistillate「PartialcondenserwithvaporjnHliquidH囪ill呂WDistillatevaporFraction:ID至此“DSTWU”B2模塊設置結束，點擊“Next”按鈕，運行計算程序，顯示計算收斂。在“Blocks-Results”子目錄窗口的“Summary”頁面，可看到完成指定分離任務，精餾塔簡捷計算的結果?？梢娮钚』亓鞅?.9055,最小理論塔板數(shù)7.198,回流比1.358時的實際塔板數(shù)14,對應的進料位置9；精餾塔的頂、底溫度分別為67.05℃和106.85℃。Summary|Balance|RefluwRatioProfileResultsMinimumrefluxratio:0.90554621ActualreHuwratio;1.35831931Minimumnumberofstages:7.19837556Numberofactualstages:13,3754161Feedstage:8.77484718Numberafactualstagesabovefeed;7.77434710Rebuilt=rheatingrequired2114.20234kWCondensercoolingrequired:2077.2853kWDistillatetemperature:67,0475271CBattorntemperature;106.847173CDistillatetofeedfraction:0.3224584HETP:在“Blocks-StreamResults”子目錄窗口的“Material”頁面，可看到精餾塔進、出口物流各組分的流率、組成和多種物性。塔頂流率2844.767kg/h,甲醇摩爾分數(shù)為0.97366，塔底流率為3404.320kg/h，甲醇摩爾分數(shù)達0.00167，滿足分離要求。2.2.3甲醇-水精餾塔的嚴格算法由以上簡捷計算，取回流比R為1.358，D/F為0.322根據(jù)奧康奈公式：E=0.49(3)-0.245=0.49(4.1x0.34)-0.245=0.452，初步估計板效TL率為45%，得到精餾段板數(shù)：8/0.45=17.78，提餾段板數(shù)：5/0.45=11.11，總板數(shù)：18+12+1=31；第19塊塔板為進料板。點擊ModelLibrary橫條上的“Columns"。選擇“Radfrac”模塊，拖放到工藝流程圖窗口，用物流線連接精餾塔的進、出口。為便于閱讀，對精餾塔的進、出口物流更改名稱。

圖4嚴格塔模型雙擊“Radfrac”模塊，出現(xiàn)精餾塔嚴格計算的子目錄設置窗口。在“Configuration”頁面，把簡捷計算結果填入相應的空格，如下圖所示。^Configuration|5beams|^Pressure|yCondenser| ThermosiphonConSelupoptionsCalculaliontype:EquilibriumT-Nurnberofstages:31StagewissrdCondenser:Total▼Reboiler:KettleTValidphases;Vapor-LiquidConvergence:StandardOp&rstirgspeciJicatiorisReHiiwrstic ,Mole 二|1.358Distillatetofeedratio▼Mole;]0.322Freewaterrefluwratio:1Feedbasis在“Streams”頁面，填入進料位置為19JConfigLirationdStreams PressureCondenserThermosipFeedstreamsNameStageConventionF19Above-StageProductstrAamsNameStagePhaseBasisD1LiquidMoleW31LiquidMole在“Pressure”頁面，填入塔頂壓力和板壓降View:TopView:Top/BottomIopstage7CondenserpressureStage1/Condenserpressure:11。kPa色nJiaujcjpi u」卜“iuiiaij存Stage2pressure:115kPaT「Conderiserpressurediop:almPressuredropforrestofcolumn(oplional]CSlagepressuredrop:atmTFColumnpressuredrop:15kPa▼點擊Blocks下的B1中的setup的Vapor-liquid,選擇默弗里效率（單板效率）Vapor-2ndLiquid^Optians：^VVapor-Liquid|\>apor-1stLiquidVapor-2ndLiquidEfficiencytype「VaporizationefficienciesmMurphreeefficienciesMethod3Specifystageefficiencies「Gpetifyefhcienciesforirdividualc&nripcn&nts「Specifyefficienciesforcalurnnsections點擊Next，設置板效率至此，精餾塔嚴格計算需要的信息已經(jīng)全部設置完畢。點擊'Next”按鈕，軟件詢問是否運行計算，點擊“確定"。在'Material”可以查看物料計算結果，塔頂甲醇的摩爾分數(shù)達到97.63%，塔底甲醇的摩爾分數(shù)為0.1086%，達到題目的設計要求。MaterialHeatLoadVol.^Curves：Wt.%CurvesPetro.CurvesDisplay:| 囚|Format:[ Q|St「eamTab同F(xiàn) 三D 二W 二TemperatureK360.1340.2380.1Pressuredim1.3821.08G1.283yaporFrac0.0000.0000.000HoleFlowkmol/hr278,54083,630188,850M-assFlowkg/hr6249.0872844.0253405.0G1yolunrieFlowl/mir127.53G63,823E2.342EnthalpyGcal/hr■17,681■5.040■12,609MoleFlowkmol/hrCH408776887.5E30.205H20130,7722.127188,645在“Blocks-Profiles”子目錄窗口的“TPFQ”頁面，可看到精餾塔各板上的溫度分布和兩相流率分布。觀察濃度變化，發(fā)現(xiàn)第19塊塔板組成與進料組成接近，無需修改進料位置。__LdB的??；|Hole二|■HydraulicsReactiorisTPFQ 匚omp0牙iti口n* K-Vslues■HydraulicsReactiorisStageCH40H20140.579799850.42020015150.522706640.47729336160.4E4456780.53554322170.407648760.59235124180.355308350.644631￡5?190.31119GG7O.G880O233200.233827180.70617282210.2706916S0.72930S32220.240676740.75932326230.203301250.79663875240.153683570.840316+3CompositionprofilesJ

在“Blocks-ResultsSummary”子目錄窗口的“Summary”頁面，可看到精餾塔嚴格計算部分結果。在“View”欄中選擇“Condenser/Topstage”，可看到塔頂?shù)挠嬎憬Y果，塔頂溫度為67.0℃，冷凝器負荷為-2067.803kW。SummaryBalance1SplitFractior1ReboilerUtilitiesStageView: |Cunden5：erTops：tage ▼|Basis:|HoleTCondenser/TapslageperJormanceTemperature:E7.0064501C▼SubcooledTemper^ture:Heatduty;-2067.S03kW一Subcooledduty:▼Distillaterate:69,68988kmol/hr▼FlRIuxrate:121.798557kmol/hrRefluwratio:1.358Freewaterdistillaterate:,dFreewaterrefluwratio:在“View”欄中選擇“Reboiler/Bottomstage”，可看到塔底的計算結果。塔釜再沸器的溫度為106.96°C，再沸器熱負荷為2105.22kW。Summary|Balance|SplitFraction|Reboiler|UtilitiesStageUtilities|View: |ReboilerButtornstage▼|Basis: |MoleFieboiler/BottoinstageperfomanueTemperdlure：10G,9564043Heatduty:2105.22449fkW V|Bottomarale:188.85012|kmol/hr t"|Boiluprate;106.308704|kmol/hrBoilupratio:0.989^39在“Blocks-Profiles”子目錄窗口的“TPFQ”頁面，可看到精餾塔各板上的溫度分布和兩相流率分布。StageTemperatureCPressurekPaHeatdutykWLiquidfromkmol/hrVaporfromkmol/hr167.0064501109.999996-2067.803211.4887370268.3558151114.9999970121.939629211.488737368.7009431115.5172380121.636195211.629509469.0813911116.0344790121.282889211.326075569.5019261116.551720120.870243210.972769669.9715601117.0689620120.392663210.560123770.4950111117.5862030119.839329210.082543871.0815531118.1034450119.200122209.529209971.7405831118.6206870118.464317208.8900021072.4824491119.1379270117.623012208.1541971173.3182091119.6551690116.666019207.312892

1274.2590461120.172410115.59322206.3558991375.3152901120.6896520114.403992205.28311476.4938221121.2068930113.129419204.0938721577.7964821121.7241340111.789874202.8192991679.2125551122.2413750110.439279201.4797541780.7108491122.7586170109.15672200.1291591882.2328661123.2758590108.025246198.84661983.6687071123.79310383.234199195.1844212084.3478971124.3103410382.273305194.3840792185.2593711124.8275820381.009754193.4231852286.4984041125.3448240379.434937192.1596342388.1929351125.8620650377.627663190.5848172490.4921411126.3793070375.828805188.7775432593.4921901126.8965480374.450016186.9786852697.0385281127.4137890373.907174185.59989627100.559132127.931030374.180243185.05705428103.358019128.4482720374.811245185.33012329105.17774128.9655140375.384036185.96112530106.220217129.4827550375.738824186.53391631106.956404129.9999962105.22449188.85012186.888704可以查看液相組成圖：

查看運算結果，見表2，塔頂甲醇的質量分數(shù)98.46%，塔底水質量分數(shù)為0.0037%，塔頂溫度為98.53℃，塔釜溫度為110.30℃。滿足題目分離要求。表2.精餾塔物料分離數(shù)據(jù)塔頂（甲醇）數(shù)據(jù)進料數(shù)據(jù)塔釜（水）數(shù)據(jù)TemperatureK360.143482340.156444380.106398Pressureatm1.381692571.085615591.28300025VaporFrac000MoleFlowkmol/hr278.5489.68988188.85012MassFlowkg/hr6249.086652844.025463405.06119VolumeFlowl/min127.53581563.823310962.3419883EnthalpyGcal/hr-17.681242-5.0397898-12.609255MoleFlowkmol/hrCH4O87.76795487.56310460.20484945H2O190.7720462.12677544188.645271在Blocks中，選擇Profiles,查看Hydraulics（水力學）數(shù)據(jù)。利用Excel計算精餾段和提餾段的各參數(shù)平均值表3.精餾段和提餾段的各參數(shù)平均值平均值 精餾段 提餾段 進料參數(shù)單位液相氣相液相氣相液相溫度℃72.2174.1394.7196.5083.67質量流量kg/h3483.846169.877249.214336.346249.08體積流量m3/s0.0012761.36820.0023291.24890.002126分子量28.3729.8519.8922.0522.38密度kg/m3762.531.251870.250.926821.55粘度cP0.33420.01150.29310.01250.3229表面力mN/m29.87 1.538 53.39 0.749 47.62第三章塔板塔體工藝尺寸計算塔徑計算精餾段的氣、液相體積流率為V1=1.3682m3/sL1=0.001276m3/s提餾段氣、液相體積流率為V2=1.2489m3/sL1=0.002329m3/s取板間距：HT=0.45mAspenplus不僅能對精餾塔的物料衡算進行模擬計算，利用“TraySizing”功能還能對模型進行塔盤以及塔板的流體力學驗算進行設計計算。1）塔盤參數(shù)的設計該塔從塔頂分出甲醇餾分，因甲醇的餾分流量小，氣相負荷小，塔徑小，采用單流型篩板。在“Tray512血8”子目錄，再點擊“New”按鈕，創(chuàng)建一個塔板模擬對象，點擊“OK”。在“Specification”頁面，根據(jù)精餾塔的實際塔板數(shù)，扣去冷凝器和再沸器兩塊板，從第2板到第30板計算塔板性質。選擇Sieve（篩板塔）。在下圖中，設置塔板間距0.45m。^/Specifications|^/Specifications|DesignResultsProfiles301TravedsectionStartingstage:2 Endingstage:Traytype;Sieve 工Numbercfparses;Tr儂geometryTrayspacing:Minimunncolumndiameter:Capslotareatoactivearearatio:Sieveholeareatoactivearearatio:然后點擊運行，觀察計算結果。在“Blocks-traySizing”子目錄的“Results”頁面?？梢圆榭此P直徑為1.060米，堰長為0.7704米，AF0.100TrSpecificationsDesignResultsProfilesSectionstartingstage:Sectionendingstage:Stage所由maximumdiameter:2302Columndiame^r;1.06026674|meter 二|Downcomerarea/Columnarea:Sidedawncomervelocity：Sideweirlength:0.0999995G0.01S30514m/sec二0.77040081meter 二在“Profiles”頁面，列出了各塔板降液管上的截面積數(shù)據(jù):表4.降液管數(shù)據(jù)StageDiametermeterTotalareasqmActiveareaperpanelsqmSidedowncomerareasqm21.060266740.882917570.706334850.0882913731.057324020.878023380.70241950.0878019541.054143630.872749190.698200150.0872745351.050686130.867033510.69362760.0867029661.046908550.860810140.688648910.0860806271.042759140.854000040.683200840.0853996181.038182710.846520460.677217180.0846516591.033119180.838283140.670627330.08382792101.027506960.829200250.663361030.08291962111.021288130.81919340.655355560.08191893121.014418240.808209550.646568480.08082054131.006881780.796245240.636997050.0796241140.99871630.783383020.626707290.07833788

150.99004220.769834370.615868520.07698293160.981094170.755981680.604786620.07559755170.972232780.742387070.593911180.07423796180.965239670.731745750.585396950.0731744190.968763280.737097970.589678860.07370957200.961769890.726494340.581195960.0726492210.952850540.713081960.570466050.07130797220.941710570.696505850.557205160.06965035230.928368570.67690970.541528240.06769074240.913532110.65544690.524358020.06554446250.898928680.634658860.507727590.06346565260.88693490.617836230.494269490.06178338270.879033380.606876910.485502040.06068745280.87467680.600876320.480701580.06008739290.872331960.597658980.478127710.05976565300.870933360.595744070.476595780.05957416310.804540580.508376880.40670190.0508375320.803107410.50656730.405254230.05065654330.802106730.505305710.404244960.05053038340.801293750.504281910.403425920.050428向上圓整塔徑，取塔徑為1.1m塔截面積為A=1D2=3.1415xl.12=0.95T4 4精餾段實際空塔氣速u=-V=137=1.442m/sAT0.95提餾段實際空塔氣速u=——=——=1.316m/sAT0.953.2精餾塔有效高度計算35塊塔板，需要三個人孔，每個人孔高度為0.8m,則精餾塔有效高度為:Z=0.45X(31-2)+(0.8-0.45)x3=14.1m3.3塔板主要工藝尺寸的計算3.3.1溢流裝置計算因塔徑D=1.1m，可選用單溢流弓形降液管，采用凹形受液盤。各計算如下。

(1)堰長lW由AspenPlus的計算結果可知，當塔盤直徑為 1.060m時，堰長為0.7704m。取lW=0.782+1.076x1.1=0.799。(2)溢流堰高度hW出口堰高：本設計采用平直堰，堰上液高度hOw按下式計算2.84h2.84h= ow10002/3(近似取E=1)a.精餾段Lh1=3600L1Lh1=3600L1=4.9752kg/hhOW2.84(4.9752\2/3 x1000I0.785)=0.00973mhW=hL-hOW=0.06-0.00973=0.05027mb.提餾段Lh2=3600L2=6.8652kg/h7, 2.84(6.8652\2/3八?h'= x =0.01206mOW1000I0.785)h'=h'—h'=0.06—0.01206=0.04794mWLOW(3)弓形降液管的寬度和橫截面已知：lw=0.727，查圖5：D

AW得到：AF_0.100,-^D_0.150AW得到：AF_0.100,-^D_0.150，則:TAF=0.100x0.95=0.095m2WD=0.150x1.1=0.165m驗算降液管停留時間：9精餾段：AH_0.095x0.459提餾段：Ls1AH's21.382x10-3=30.93s0.095x0.45 :22.417s1.907x10-3停留時間9>5s,故降液管可使用。(4)降液管底隙高度a.精餾段取降液管底隙流速u=0.08m/s,貝I仆_廠4_0.0216m0 0lWu0hW-h0_0.05027-0.0216_0.0287m〉0.013m故降液管底隙高度設計合理。選用凹形受液盤，深度卜=501^Wb.提餾段取降液管底隙流速u'c=0.08m/s,則h'=4_0.0298m0 0lWu0'h'-h'_0.04794-0.0298_0.01814m〉0.013mW0故降液管底隙高度設計合理。選用凹形受液盤，深度卜二50mmW3.3.2塔板布置(1)塔板的分塊本設計塔徑D=1.1m。采用分塊式塔板，以便通過人孔裝拆塔板。根據(jù)查表5,塔板分3塊。表5.塔板分塊數(shù)塔徑/mm塔板分塊數(shù)800~120031400~160041800~200052200~24006（2）邊緣度寬度確定如圖是塔板的結構示意圖：圖6.塔板的結構示意圖取邊緣區(qū)寬度WC=0.035m,破沫區(qū)寬度Ws=0.065m。（3）開孔區(qū)面積計算開孔區(qū)面積Aa按下式計算：TOC\o"1-5"\h\za?.———-.冗r2 .4、A=2（x.;r2—x2+ arcsin_）\o"CurrentDocument"a、 180rD 1.1x=_-(W+W)=--(0.165+0.065)=0.32m22其中D1.1r=-W=--0.035=0.515m2c2A=2x(0.32A=2x(0.32x、;0.5152—0.322a3.14義0.5152 .0.32+xarcsin1800.515)=0.614m2（4）篩孔計算及其排列選用3=2mm不銹鋼板，取篩孔直徑為d=5mm0篩孔按正三角形排列,取孔中心距t=3d。=3x5=15mm篩孔數(shù)目1.155xA121.368x0.6140.015—=3734個=22.06m/s==22.06m/s=20,14m/s開孔率為fdV (0005V(P=0.907t=0.907x =10.1%ItJ (0.015)精儲段氣體通過篩孔的氣速_V_ 1.3682o0.101x0.614o提僧段氣體通過篩孔的氣速，—V_1.2489o0.101x0.6140第四章篩板流體力學驗算4.1塔板校核核算“塔徑1m”時的壓降。點擊“Blocks-TrayRating”子目錄，再點擊“New”按鈕，創(chuàng)建一個塔板模擬對象，點擊“OK”。^/ObjectManagerjNameStatusObjectmanagerNameStatusObjectmanager*/Specs在“Specs”頁面，填入“塔徑1.1m”等數(shù)據(jù)。然后點擊運行，觀察計算結果。*/SpecsDesign/Pdrop]Layout]Downcomers301Tracedsection2-±JSieveStartingstage:Trayt^pe:Endingstage:Numberofpasses:TraygeometryDiameter:1.1meter0.45m&terDiameter:1.1meter0.45m&terDeckthickness:|~)GAUC ▼|Trayspacing:在“Blocks-B5-trayRating”子目錄的“Results”頁面，可見塔徑1.1m時的最大液泛因子0.745（小于0.8）；全塔壓降15.24kPa，符合題目要求；最大降液管液位/板間距為0.3063（在0.2~0.5之間）［3。］塔板校核通過。

在“Profiles”頁面，可看到各板上液泛因子、降液管流速、降液管持液量、壓降等數(shù)據(jù)。表7.液泛因子表StageFloodingfactorDowncomervelocitym/secDowncomerbackupmeterBackup/TrayspacePressuredropkPaDowncomerres.timesec20.7445580.0151450.1378370.3063050.55726029.712730.7405550.0149950.1373380.3051950.55473230.009240.7362530.0148230.1367880.3039730.55204230.358750.7316010.0146240.1361810.3026240.54917230.771360.7265440.0143960.1355090.3011310.54610731.259170.7210220.0141340.1347630.2994740.54283231.837180.7149660.0138360.1339350.2976340.53933832.523390.7083030.0134980.1330160.2955920.53562633.3393100.7009620.0131150.1319980.2933300.53170834.3111110.6928760.0126870.1308750.2908340.52761735.4686120.6840000.0122130.1296460.2881020.52341336.8453130.6743270.0116960.1283140.2851410.51919338.4751140.6639160.0111420.1268940.2819860.51509440.3860150.6529350.0105660.1254150.2787000.51129242.5875

160.6416870.0099880.1239250.2753880.50797745.0520170.6306260.0094350.1224860.2721910.50530647.6924180.6220240.0089380.1212700.2694890.50412850.3494190.6249530.0305080.1358890.3019760.54239214.7503200.6161900.0299620.1348190.2995980.53829915.0193210.6050950.0292370.1334480.2965500.53334215.3917220.5913660.0283050.1317420.2927610.52758515.8982230.5751110.0271650.1297240.2882760.52135816.5655240.5572760.0258690.1275110.2833580.51533817.3951250.5399670.0245560.1253480.2785510.51043918.3253260.5259290.0234270.1235520.2745610.50731619.2087270.5167630.0226320.1223270.2718390.50583519.8830280.5117360.0221710.1216290.2702860.50526520.2966290.5090410.0219380.1212700.2694890.50498720.5121300.5074410.0218290.1210900.2690890.50474920.61464.2塔板壓降4.2.1干板阻力h「計算C干板阻力計算式：a.精餾段

hC=0.051(22.72Y(1.268\10.735；1757.06；=0.0816m液柱B.提餾段h'hC=0.051(22.72Y(1.268\10.735；1757.06；=0.0816m液柱B.提餾段h'=0.051C(20.99Y(0.925)10.735；1869.43；=0.04425m液柱4.2.2氣體通過液層的阻力、計算L計算:XhLa.精餾段V S1——A—ATf1.4089 二1.648m/s0.95—0.095F=u和=1.648x<1.268=1.856kg1/2/(s?m1/2)查圖8Fn圖8.充氣系數(shù)關聯(lián)圖得8=0.56。故h=ph=0.56x0.06=0.0336m液柱b.提餾段u’u’a s= =1.522m/sAT-Af 0.95-0.095=u=1.522x.J0.925=1.464kg1/2/(s?m1/2)查圖7,得8=0.61。故h'=ph'=0.61x0.06=0.0366m液柱LL4.2.3液體表面力的阻力計算

a.精餾段液體表面力所產(chǎn)生的阻力h。：入 4o 4x27.81x10-3h= l-= =0.003mMft。pLgd0757.06x9.81x0.005氣體通過每層塔板的也柱高度hp可按下式計算hp=hC+4+h=0.0816+0.0336+0.003=0.118m液柱氣體通過每層塔板的液柱高度hp按下式計算Ap=hpL1g=0.118x757.06x9.81=876Pa<0.88kPa（設計允許值）b.提餾段液體表面力所產(chǎn)生的阻力h。：h'=/鼠= 4X53.12X10-3一=0.00498m液柱。pM 869.43x9.81x0.005氣體通過每層塔板的也柱高度hp可按下式計算h'=h，+h'+h'=0.04425+0.0366+0.00498:0.0858m液柱PClo氣體通過每層塔板的液柱高度hp按下式計算Ap'=h'pL2g=0.0858x869.43x9.81=732Pa<0.88kPa(設計允許值)液面落差對于篩板塔，液面落差很小，且本塔的塔徑和液流量不大，故可以忽略液面落差的影響。液沫夾帶3.2液沫夾帶量計算:3.25.7X10-6e二 V OLhf=2.5hL=2.5x0.06=0.15ma.精餾段5.7X10-5.7X10-3(1.648 X27.8110.45-0.15)3.2:0.0478kg液/kg汽<0.1kg液/kg汽b.提餾段5.7X10-5.7X10-3(1.522 X53.1210.45-0.15)3.2=0.0194kg液灰8汽<0.1kg液氽8汽故本設計液沫夾帶量eV在允許圍。4.5漏液對篩板塔，漏液點氣速uo,min可由下式計算u0i:4.4c0d(0.0056+0.13hL-h。)pL/pVa.精餾段u0i:4.4x0.735x、/(0.0056+0.13x0.06-0.003)x757.06/1.268:8.059m/s實際孔速uo=22.72m/s>uomin,則穩(wěn)定系數(shù)K二K二-u0-u0,min =2.82>1.58.059b.提餾段u0i:4.4x0.735x、/(0.0056+0.13x0.06—0.00498)x869.43/0.925:9.098m/s實際孔速u,=20.99m/s〉u, ，則穩(wěn)定系數(shù)0 0,minu，

u，

K二——0—

u'0,min—―=2.31>1.59.098故本設計中無明顯漏液。4.6液泛為防止塔發(fā)生液泛，降液管液層高Hd應服從下式關系H<<甲(H+h)TW其中Hd=hP+%+hdh=0.153(uu)2=0.153x0.082=0.001m液液甲醇-水物系屬一般物系，取@=0.5a.精餾段叭HT+h印)=0.5x(0.45+0.05027)=0.250mHd=0.118+0.0336+0.001=0.1526m液液b.提餾段3H；+h；)=0.5x(0.45+0.04794)=0.249mH'=0.0858+0.0366+0.001=0.1234m液柱dH<<p(H+h)，故本設計中不會發(fā)生液泛。TW第五章塔板負荷性能圖5.1漏液線由U0.=4.4c3(0.0056+0.13hL—h。)pJPyu0,minVs,minA0u0,minVs,minA0，VA*hOW，hOW2.8410002/3a.精餾段Emm=4.4c0A0N0.0056+0.137 2.84h+ w10002/3=4.4x0.735x0.101x0.614N0.0056+Emm=4.4c0A0N0.0056+0.137 2.84h+ w10002/3=4.4x0.735x0.101x0.614N0.0056+0.130.05027+2.84(3600Ls丫/31000<0.785；-0.003757.061.268化簡得到：V.=4.90xJ0.00945+0.102L/3b.提餾段r<0.0056+0.131h+也E(Lh12/3w1000Il1, 'W'_2.84(3600Ls丫/3=4.4x0.735x0.101x0.614：<0.0056+0.130.04794+Emm=4.4c04100010.785)-0.00498869.430.925化簡得到：Vs,min5.2液沫夾帶線=4.90x,50.00685+0.102Lm以eV=0.1kg液/kg氣為限，求Vs-Ls關系5.7x10-63.2a.精餾段V

s1——A-ATfV

s1

0.95-0.095=1.170Vs1h=2.5h=2.5(h+h),hWOW:0.05027whOW=0.7839L2/3S2.84(3600L,hOW=0.7839L2/3S100010.785S/H—h=0.45—2.5(0.05027+0.7839D/3)=0.324—1.96D/3Tf S S5.7x5.7x10-3 x27.813.2(1.170VA

S1——I0.324-1.96L2/3I' S7

=0.1kg液做汽整理得V=1.916-11.59L2/3s1 s1b.提餾段U'=——-Xs = ^s2 =1.170VaA-A0.95-0.095 s2Tfh'=2.5h'=2.5(h'+h'),f L WOWh'=0.04794whhOW2.84(3600L,A2/31W10.785s?=0.7839L2/3SH-h=0.45-2.5(0.04794+0.7839D/3)=0.330-1.96D/3Tf S S5.7x10-353.12(1.170VAX s2——I0.330-1.96L2/3IS=0.1kg液做汽整理得V=2.389-14.19L2/3s2 s25.3液相負荷下限對于平直堰，取堰上液層高度hO=0.006m作為最小液體負荷標準。hOW2.8413600L、2/3 E 10001lJ=0.006，取E=1Ls,min(0.006x1000A3/20.785I2.84J3600=0.00067m3/s5.4液相負荷上限以0=4s作為液體在降液管中停留時間的下限nAHv=_f-T,LL s,mins°.°95X°.45=0.010695.5液泛線計算：(pH+((p-P-l)7i=(P+l)7i+h+h+hT W OWcdG忽略/Z,將各個關系式代入，整理得：aV2=br-c'l2—dZ2/3其中:0.051b'=^H+(cp-P-l)/iT 1c'=0.153/Ch)W0t/r=2.84xlO-3E(l+p)t/r=2.84xlO-3E(l+p)2/3a.精鐳段=0.04112,b'=0.1717,c'=532.16,d'=1.223V2=4.1756-12941D-29.742D/3b.提鐳段a'=0.02612,b'=0.1718,c'=279.59,d'=1.262V2=6.5773-10704Z2-48.315D/3根據(jù)以上計算，用幾何畫板軟件，分別畫精僧段和提儲段的篩板塔負荷性能圖。結果如圖9和圖10。由圖看出，該篩板的操作上限液沫夾帶線控制，下限由液相負荷下限控制。a.精僮段查圖可得：V=1.75m3/s,V=0.68m2/s,故操作彈性為：s,max s,minV 1.75c5-s，max= =2.57V 0.68s,minb.提僧段s,min2.090.67=3.12圖9.精餾段塔板負荷圖圖10.提餾段塔板負荷圖Flash□plionsPSDComponentAttr.EOOptions熱水流量暫時寫作Flash□plionsPSDComponentAttr.EOOptions熱水流量暫時寫作300kmol/h，然后用“Design-spec”功能求取準確值。第六章塔換熱器設計6.1原料預熱器設計根據(jù)2.7節(jié)工藝計算結果，對精餾塔的進料前換熱器進行設備設計計算，為一步嚴格計算提供數(shù)據(jù)。在aspen工作界面選擇HEATX模塊，物流交換如下圖所示：圖11原料進料換熱器設計模塊1)進行預熱器的簡捷計算。首先添加換熱介質水到計算系統(tǒng)中。^/Selection|Petroleum|Noncon7entional|^/Databanks)DefinecoMponentsComponentIDTypeComponentnameFormulaCH40CariYendQnalMETHANOLCH40H20ConventionalWATERH20米添加進口物流性質。加入塔頂進入冷凝器蒸汽性質。由“Streams-Specifications中填寫如下數(shù)據(jù)：*/Specifications|

在“Blocks-Setup”子目錄，有4個頁面，只需要填寫“Specifications”頁面。規(guī)定進料物流換熱后的溫度達到進入精餾塔的為泡點。/Specifications!LMTD1PressureDrop1-^UMethods1FilmCoefficients：Calculaticin(*ShortcutCalculaticin(*Shortcut「DetailedrShellScTube「AirCooledrPlateTransferUA

toshortcutHotfluid: ▼Flowdirection: 同卜No.shellsinseries:1「CalculatenumberofshellsType: |DesignEwchangerspecificationExchangerTvpe:|HeatexchangerEwchangerspecification模擬計算運行并查看結果。在“Blocks-ThermalResults”子目錄有5個頁面。在“Summry”頁面可看到兩流體進、出口的性質參數(shù)，其中高溫蒸汽出口溫度變?yōu)?8.1℃。HeatHresultsHotstream:Iemperature;HeatHresultsHotstream:Iemperature;Pressure:Vaporfrsction:Coldstream:Iermperature:Pressure;Vaporfrscztion:Heatdutp:HWLW120.00000EC▼52,6542231k199.9999940kPa▼199.999994□kPa▼FOUT25,0000061C▼83,8141011C▼124.99999E0kPa▼124.9999961°kPaInlet 0utlet[431738128fkW_V]在“ExchangerDetails”頁面，可看到熱負荷139.68K可需要的換熱面積125.66m2、傳熱系數(shù)624.03kcal/hr-sqm-k、傳熱溫差42.5℃等數(shù)據(jù)。ExchangerdetailsCalculatedheatduty:431.738128kWRequiredewchangerarea:16,008236：i：qrriActualexchangerarea:16,008236sqmPercentover(under)design:0AverageU[Dirty):0.85kJ/sec-sqm-KAverageU[Clean]:UA:13,6070013kJ/s：ec-KLMTD(Corrected):31,7291162KLMTDcorrectionfactor:1Thermaleffectiveness;Numberoftransferunits:Numb&rofsheikinseries:1Numberofshellsinparallel:由上述結果給出熱負荷431.74KW、需要換熱面積16m2、總傳熱系數(shù)0.85kJ/s?m2?k、傳熱溫差等31.7℃等數(shù)據(jù)，選擇浮頭式換熱器。6.2冷凝器的選擇輸入冷卻水物流信息A/Specification￡|FlashOptionsPSDComponentAttr.EOOptioiGutistreamnarrie:J輸入冷卻水物流信息A/Specification￡|FlashOptionsPSDComponentAttr.EOOptioiGutistreamnarrie:JMIXEDRefTemperatureI輸入塔頂物料信息輸入塔頂物料信息SpecificationFlashOplionsPSDComporiertAttr.SpecificationFlashOplionsPSDComporiertAttr.EOOptionsSubstreamname:|7MIXEDFiefTemperdtureSubstreamname:|7MIXEDFiefTemperdture設置目標ySpecifications^LMTD|PressureDropjMelhods：jFilmCoefficients：CalculationC*Shortcut「DetailedCShell&Tube「AirCooled設置目標ySpecifications^LMTD|PressureDropjMelhods：jFilmCoefficients：CalculationC*Shortcut「DetailedCShell&Tube「AirCooledrPl^teTransferUA

toshortcutFlowarrangementHotfluid;Flowdirection:No.shellsinseries:Countercurrent|▼CalculatenumberofshellsType:|DesignEKthangerType;|Hedtexchanger _|運行，查看結果SummaryIBalanceIExchangerDetailsIPresDrop/VelocitiesIZonesHeatwresultsInletOutletHotstream:HIHOTemperdture:67,54732E1C 二67,0062591C jr]Pressure:1.085G1559.atm ▼1.08561559atm 二]Vaporfraction:10Coldstream:ClCOTemper-dture:25,0000061c 二51.3980B51C 二Pressure:1 atm 二1 atm ;Vaporfraction:0[5 Heatdutp:2065.84608kW 6查看換熱器面積為90m2。EMchargerdetailsCalculatedh已已tduty2065.S460SkWRequiredewchangerarea:83,8532431sqm配加寸exchanger翻骨：89.SE22421sqmPercentover(under)design:04verageU|Dirty]:0.85kJ/5ec-sqm-K^.verageU[Clean]:LIA:76,3752604kJ/sec-K.LMTD(Corrected):27.04SE289K選擇BESXY>00-1.6-200-4519-4REB(b)浮頭式換熱器輸入塔底物料信息選用200℃的飽和水蒸氣加熱^/SpeciFications|FlashOptions]PSD|ComporientAttr.|EOOptions：|Costing|設定目標SpecificationsLMTDPressureE-iropJUMethods|FilmCoefficientsCalculation(*ShortcutCDelailedrShellHubeC'AirCooledCPlateTransferUA

t口shortcutFl口同arrarigemeritHotfluid: 二Flowdirection: 雇］No.shells：inseries:1「CalculatenumberofshellsType: |Design 三］EwchangerType:|Heatexchanger|ColdstreamoutletvaporJraction色0.4974|Specification:Value:Ekchangerarea:ConstantUA:Minimumtemperatureapproach:pqnri |Ical/sec-hI1k色查看結果HeatsresultsHotstream:Temperature:Pressure;Vapcrfraction:Coldstream:Tempera^ure;Pressure:Vaporfraction:Heatduty:InlH OutletHl|H0200.000006CT169.120578C▼15,31346221atmT15.3134喀0atmT□CO380.106153K▼380.260334K▼1.28300025□atm▼1.28300025|0.4974-atm▼|2101.94087 V|第七章塔附件設計7.1接管7.1.1進料管進料管的結構類型很多，有直管進料管、彎管進料管、1型進料管等本設計采用直管進料管。管徑計算如下：取uF=0.8m/s,PF=816.42kg/m34.5x1073600x300x24x816.42=2.1265x10-3m3/s4x2.1265x10-3D=i =0.058m=58mm、13.14x0.8查標準系列選取祖70X47.1.2回流管t；4Vd=1 si—R\'，nUFPD: 4x1.4089\：3.14x0.8x757.06=0.054m查表取370X47.1.3塔底出料管'4WM :~~4x188.72x18.04….w=1=0.042md=WtnuFpW33.14x0.8x869.43x3600查表取360X47.1.4塔頂蒸汽出料管直管出氣，取出口氣速u=20m/s,則' 4x6906D=: =0.349m=349mm\：3.14x20x3600查表取3355X97.1.5塔底進氣管采用直管，取出口氣速u=15m/s,則,4x34985D=■ =0.287m=287mm\：3.14x15x3600查表取6325X97.