化工原理課程設(shè)計(jì)任務(wù)書

化工原理課程設(shè)計(jì)任務(wù)書設(shè)計(jì)題目浮閥式連續(xù)精餾塔及其主要附屬設(shè)備設(shè)計(jì)工藝條件生產(chǎn)能力：13200噸/年（料液）年工作日：300天原料組成：50%甲醇，50%水（質(zhì)量分率，下同）產(chǎn)品組成：餾出液98%甲醇，釜液0.8%甲醇操作壓力：塔頂壓強(qiáng)為常壓進(jìn)料溫度：泡點(diǎn)進(jìn)料狀況：泡點(diǎn)加熱方式：直接蒸汽加熱回流比：自選設(shè)計(jì)內(nèi)容確定精餾裝置流程，繪出流程示意圖、塔器設(shè)備圖。工藝參數(shù)的確定基礎(chǔ)數(shù)據(jù)的查取及估算，工藝過(guò)程的物料衡算及熱量衡算，理論塔板數(shù)，塔板效率，實(shí)際塔板數(shù)等。主要設(shè)備的工藝尺寸計(jì)算板間距，塔徑，塔高，溢流裝置，塔盤布置等。流體力學(xué)計(jì)算流體力學(xué)驗(yàn)算，操作負(fù)荷性能圖及操作彈性。主要附屬設(shè)備設(shè)計(jì)計(jì)算及選型塔頂全凝器設(shè)計(jì)計(jì)算：熱負(fù)荷，載熱體用量，選型及流體力學(xué)計(jì)算。料液泵設(shè)計(jì)計(jì)算：流程計(jì)算及選型。設(shè)計(jì)結(jié)果總匯主要符號(hào)說(shuō)明參考文獻(xiàn)裝置流程圖工藝參數(shù)的確定1.物料衡算T生產(chǎn)能力為13200噸/年，進(jìn)料甲醇組成為50%(m)餾出液98%甲醇，釜液0.8%甲醇。甲醇M1=32.0kg/kmol,水M2=18.0kg/kmol.???Xf=(0.5/32)/(0.5/32+0.5/18)=0.36Xd=(0.98/32)/(0.98/32+0.02/18)=0.965Xw=(0.8%/32)/(0.8%/32+99.2%/18)=0.45%料液平均摩爾量M=32*0.36+18*0.64=23.04kg/kmol料液流量F=13200*10八3/(300*24*23.04)=79.57kmol/h由總物料守恒有：F+S=W+D對(duì)甲醇有：F*Xf=W*Xw+D*Xd對(duì)于直接蒸汽加熱有：V=S丄'=WV=V-(1-q)*F,L'=L+q*F對(duì)于泡點(diǎn)加料有：V=V,L‘=L+F又TV=(R+1)D,L=R*D???L‘=W=R*D+F,S=(R+1)*D???要算得流出液，釜夜及加熱蒸汽的量，得先算出最小回流比及回流比。常壓下甲醇和水的氣液平衡表(T—x—y)T「C)XYT「C)XY92.90.05310.283476.70.33330.691890.30.07670.400176.20.35130.7374

88.90.09260.435373.80.46200.775686.60.12570.483172.70.52920.797185.00.13150.545571.30.59370.818383.20.16740.558570.00.68490.849282.30.18180.577568.00.77010.896281.60.20830.627366.90.87410.919480.20.23190.64851000.00.078.00.28180.6775-18.335x-18.335x+100.13?系列丄系列卻——多項(xiàng)武｛系列1）——多項(xiàng)式（系列3）由y=49.388*xT-73.544*x+95.708,將Xf=0.36 ,Xd=0.965,Xw=0.45%代入得到相映的溫度:Tf=75.63°CTd=70.73CTw=95.38C將Tf、Td、Tw代入y=-20.024*x"2-18.335*x+100.13得Yf=0.74Yd=0.85Yw=0.21ty=ax/(1+(a1)*x)???ci=y(x-1)/(x*(y-1))???a=0.74*(1-0.36)/((1-0.74)*0.36)=5.06cd=0.85*(1-0.965)/(0.965*(1-0.85))=0.206cw=0.21*(1-0.45%)/(0.45%*(1-0.21))=58.81a—A(1/3)=3.94Tq=1,「.心Rm/(Rm+1)=(0.965-0.689)/(0.965-0.36)=0.456?Rm=0.839取?S=(R+1)*D=2.26D由:F+S=W+D,F*Xf二W*Xw+D*Xd有：79.57+2.26D=D+W得:D=29.14kmol/hW=116.29kmol/hS=65.86kmol/h2.理論塔板數(shù)的計(jì)算精餾段操作線方程：y=R/(R+1)x+Xd/(R+1)y=0.558x+0.427提餾段操作線方程：y=W*x/S-W*Xw/S=1.766x-0.00795利用作圖法得到，理論塔板數(shù)NT=11進(jìn)料板為第5塊；精餾段理論板數(shù)為4塊，提餾段理論板數(shù)為7塊tTd=70.73°CTw=95.38C?T=(70.73+95.38)/2=83.06Cy‘=0.58x'=0.20

平均相對(duì)揮發(fā)度a=3.9483.06C時(shí)甲醇跟水的粘度分別為口(2=0.3436mPa.s(由奧康奈爾公式Et=0.492(a由奧康奈爾公式Et=0.492(a、-0.245卩L)得E=0.492*(3.94*0.357)-0.245E=0.453二實(shí)際塔板數(shù)E=0.453二實(shí)際塔板數(shù)N=11/0.453=24.3塊取實(shí)際塔板數(shù)為25塊，其中精餾段4/0.453=8.83提餾段7/0.453=15.45塊，取精餾段9塊，提餾段16塊。年衡曲線提餾段7/0.453=15.45塊，取精餾段9塊，提餾段16塊。年衡曲線對(duì)甫線精謂段提懵段043.熱量衡算0.6塔頂冷凝器的熱負(fù)荷Qc=V*rcV=65.86kmol/h在塔頂溫度70.73C下甲醇的汽化熱r1=847kJ/kg=27104kJ/kmol水的汽化熱r2=1498kJ/kg=26964kJ/kmol平均汽化熱r=27104*0.965+26964*0.035=27099.1kJ/kmolQc=65.68*27099.仁1.780*10八6kJ/h塔釜加熱蒸汽的熱負(fù)荷Qb=V*rbV=65.86kmol/h在塔釜溫度95.38C時(shí)，甲醇的汽化熱r1=950kJ/kg=30400kJ/kmol水的汽化熱r2=1730kJ/kg=31140kJ/kmol平均汽化熱A6kJ/h三、主要設(shè)備工藝尺寸計(jì)算1.塔徑與空塔氣速1)操作壓力t塔頂操作壓力為常壓，Pd=101.33KPa取每層塔板壓降：△P=0.64kpa二進(jìn)料板操作壓力Pf=101.33+0.64*9=107.09kpa精餾段平均操作壓力P1=(101.33+107.09)/2=104.21kpa塔釜壓力Pw=101.33+0.64*25=117.33kpa提餾段平均操作壓力P2=(117.33+107.09)/2=110.77kpa2)溫度精餾段平均溫度t1=(70.73+75.63)/2=73.18 °Ct2=(95.38+75.63)/2=85,505Ct=(70.73+95.38)/2=83.055C3)平均摩爾流量S=V'=V=(R+1)D=65.86kmol/hL'=L+F=W=116.29kmol/hL=36.72kmol/hF=79.57kmol/h塔頂汽相摩爾質(zhì)量Md,y=32*0.85+18*0.15=29.9kg/kmol塔頂液相摩爾質(zhì)量Md.x=32*0.965+18*0.035=31.51kg/kmol進(jìn)料汽相摩爾質(zhì)量Mf，y=32*0.74+18*0.26=28.36kg/kmol進(jìn)料液相摩爾質(zhì)量Mf,x=32*0.36+18*0.64=23.04kg/kmol流出液汽相摩爾質(zhì)量Mw,y=32*0.21+18*0.79=20.94kg/kmol流出液液相摩爾質(zhì)量Mw,x=32*0.0045+18*0.9955=18.063kg/kmol精餾段平均汽相摩爾質(zhì)量M1,y=(29.9+28.36)/2=29.13kg/kmol精餾段平均液相摩爾質(zhì)量M1,x=(31.31+23.04)/2=27.275kg/kmol提餾段平均汽相摩爾質(zhì)量M2,y=(20.94+28.63)/2=24.785kg/kmol提餾段平均汽相摩爾質(zhì)量4）密度M2,x=(23.04+18.063)/2=20.55kg/kmol精餾段氣相密度p1

=841.65kg/m塔釜液相密度pw=1/(0.8%/722.88+99.2%/961.85)=959.31kg/m精餾段液相平均密度p3=(748.44+841.65)/2=795.05kg/m提餾段液相平均密度p4=(841.65+959.31)/2=900.48kg/m表面張力如下圖所示，在70.73C,75.63C,95.38C時(shí)，甲醇的表面張力分別為26.02mN/m,24.78mN/m,95.38mN/m水的表面張力分別為66.02mN/m,64.38mN/m,61.87mN/m7070—水■■0 20 10 60 aoLGO120???6d6f6w精餾段61=(27.42+50.412)/2=mN/m提餾段62=(50.412+61.70)/2=56.056mN/m粘度

查表得在70.73C,75.63C,95.38C時(shí)，甲醇的粘度分別為0.562mPas,0.489mPa-s,0.322mPa-s;水的粘度分別為0.4061mPas,0.3779mPa-s,0.2978mPa.sad-saf-saw-s精餾段液體平均粘度a1=(0.5565+0.4179)/2=0.4872mPa-s提餾段液體平均粘度a2=(0.4179+0.2979)/2=0.3579mPa-s7）塔徑塔板的實(shí)際計(jì)算A)精餾段汽、液相體積流率為：TOC\o"1-5"\h\z-4 3LsVS3/s塔徑的計(jì)算欲求塔徑應(yīng)先求出U,而口=安全系數(shù)XUmax欲求塔徑應(yīng)先求出U,而口=安全系數(shù)XUmaxUmax精--液相密度，kg/m3;V--氣相密度，kg/m3;C「-負(fù)荷因子，m/s;式中:橫坐標(biāo)的數(shù)值為:(Ls/Vs)(pl/、0.5Pv)=3.499*10-4/0.5056*(795.05/1.054) 0.5=0.019參考有關(guān)資料，根據(jù)塔板間距與塔徑的關(guān)系塔徑/D，m0.3? 0.5?0.8 0.8?1.6 1.6?2.4 2.4?4.0

0.5板間距/Ht,mm200?300250?350300?450350?600400?600初選板間距HT=o.4m,取板上液層高度hi=0.05m,Hrh1=0.4-0.05=0.35m045根據(jù)以上數(shù)值，由史密D.06斯關(guān)聯(lián)圖查得，0.05I?FLMG°=0.07il.fH0,02/、°.2〔叮由公式C=C20120丿校0.010正得C=0.07*(38.916/20)0.故分離空間2n耶01S0J004 0.060.08MPJU0.20OJO0.40=0.08000.5Una>=C0.5=0.0800*[(795.05-1.054)/1.054]=2.1949m/s取安全系數(shù)0.70，貝Su=0.70umax

觸故D=■u=[(4X0.5056)/(3.14X1.5364)]0.5=0.6475m所以圓整取D=0.8m???塔截面積：At=H/4*D2=0.5024m2空塔氣速u二Vs/AT=0.5056/0.5024=1.0064m/sB)提餾段汽、液相體積流率為：TOC\o"1-5"\h\zVSLs-4nVs塔徑的計(jì)算(Ls/Vs)(Pl/pv)0.5-4 05=7.372*104/0.4923*(900.48/0.921) =0.0468初選板間距HT=0.4m,取板上液層高度h1=0.05m,故分離空間HT-h1=0.4-0.05=0.35m根據(jù)以上數(shù)值，由史密斯關(guān)聯(lián)圖查得， G°=0.076由公式C=C20l20丿校正得0=0.076*(56.056/20)=0.0934UnaUna)=C「V0.50.5=0.0934*[(900.48-0.921)/0.921]=2.9189m/s取安全系數(shù)0.70，貝Su=0.70umax故D=7：u=[(4x0.4923)/(3.14X2.04323)]0.5=0.5540m

所以圓整取D=0.6m???塔截面積： AT=n/4*D2=0.2826m2空塔氣速u=Vs/AT=0.4923/0.2826=1.742m/s板間距，塔高取板間距HT=0.4m,有效傳質(zhì)塔高Z=(25-1)*0.4=9.6m溢流裝置弓形降液管，具有較大的容積，又能充分利用塔板面積，利用率較高,應(yīng)用最為廣泛，所以裝置選用弓形降液管，不設(shè)進(jìn)口堰。弓形降誡管的稚敷I精餾段弓形降誡管的稚敷堰長(zhǎng)取堰長(zhǎng)Iw由In/D=0.7,弓形降液管寬度Wd和面積Af,由右圖查得：A/A=0.089,Wd/D=0.149A二八2*0.252=0.0447mH=0.4m,hL=0.05mT二A*Ht/L八-4)=51.10>3.0s故降液管尺寸符合要求。出口堰高h(yuǎn)w=hL-how,hL=0.05m采用平直堰，堰上液層高度為=0.668*(L/Iw)八(2/3)=0.668*