化工原理課程設(shè)計(jì)苯與氯苯的分離

化工原理課程設(shè)計(jì)說明書設(shè)計(jì)題目：苯一氯苯精餾過程板式塔設(shè)計(jì)設(shè)計(jì)者：班級(jí)化工095閆宏陽(yáng)日期：2011年12月13號(hào)指導(dǎo)教師：勝凱設(shè)計(jì)成績(jī)：日期：TOC\o"1-5"\h\z\o"CurrentDocument"?設(shè)計(jì)任務(wù)書3\o"CurrentDocument"?設(shè)計(jì)計(jì)算書4\o"CurrentDocument"A設(shè)計(jì)方案的確定4＞精餾塔物料衡算4\o"CurrentDocument"＞塔板數(shù)的確定5\o"CurrentDocument"＞精餾塔的工藝條件及有關(guān)物性數(shù)據(jù)的計(jì)算8＞塔體工藝尺寸計(jì)算13＞塔板主要工藝尺寸15＞塔板流體力學(xué)驗(yàn)算17＞浮閥塔的結(jié)構(gòu)20＞精餾塔接管尺寸23＞產(chǎn)品冷卻器選型25＞對(duì)設(shè)計(jì)過程的評(píng)述和有關(guān)問題的討論25附圖：生產(chǎn)工藝流程圖精餾塔設(shè)計(jì)流程圖設(shè)計(jì)任務(wù)書（一）題目試設(shè)計(jì)一座苯—氯苯連續(xù)精餾塔，要求年產(chǎn)純度99.8%的氯苯21000噸，塔頂餾出液中含氯苯不得高于2%，原料液中含氯苯45%（以上均為質(zhì)量分?jǐn)?shù)）。二）操作條件l）塔頂壓力4kPa（表壓）；2）進(jìn)料熱狀況泡點(diǎn)；3）回流比R=l.4Rmin；4）塔底加熱蒸汽壓力0.5Mpa（表壓）;5）單板壓降W0.7kPa；三）塔板類型浮閥塔板（Fl型）四）工作日每年按300天工作計(jì)，每天連續(xù)24小時(shí)運(yùn)行五）廠址廠址為地區(qū)設(shè)計(jì)計(jì)算書一、設(shè)計(jì)方案的確定本任務(wù)是分離苯—氯苯混合物。對(duì)于二元混合物的分離，應(yīng)采用連續(xù)精餾流程，本設(shè)計(jì)采用板式塔連續(xù)精餾。設(shè)計(jì)中采用泡點(diǎn)進(jìn)料，將原料液通過預(yù)熱器加熱至泡點(diǎn)后送進(jìn)精餾塔。塔頂上升蒸氣采用全凝器冷凝，冷凝液在泡點(diǎn)下一部分回流至塔，其余部分冷卻后送至儲(chǔ)物罐。該物系屬易分離物系，最小回流比較小，故操作回流比取最小回流比的1.4倍，且在常壓下操作。塔釜采用間接蒸汽加熱，塔底產(chǎn)品經(jīng)冷卻后送至儲(chǔ)物罐。二、精餾塔物料衡算（以輕組分計(jì)算）1．原料液及塔頂、塔釜產(chǎn)品的摩爾分率苯的摩爾質(zhì)量M=78.11kg/kmolA氯苯的摩爾質(zhì)量M=112.56kg/kmolB0.55/78.110.55/78.11+0.45/112.560.98/78.110.98/78.11+0.02/112.560.002/78.110.002/78.11+0.998/112.562．原料液及塔頂、塔釜產(chǎn)品的平均摩爾質(zhì)量M=0.638x78.11+(1-0.638)x112.56=90.58kg/kmolFM=0.986x78.11+(1-0.986)x112.56=78.59kg/kmolDM=0.003x78.11+(1-0.003)x112.56=112.46kg/kmolW3．物料衡算原料處理量21000x1000W——25.93kmol/h300x24x112.46總物料衡算苯物料衡算F—D+25.930.638F—0.986D+0.003x25.93

聯(lián)立解得D=47.31kmol/h聯(lián)立解得F=73.24kmol/h三、塔板數(shù)的確定理論板數(shù)nt的求取1）由手冊(cè)查得苯—氯苯物系的氣液平衡數(shù)據(jù)，繪出x—y圖，見圖1。T/oC8090100110120130131.8po/kPaA101.33136.66179.99234.60299.99378.65386.65po/kPaB19.7327.3339.0753.3372.4095.86101.33p-pox二Bpo—poAB1.0000.6770.4420.2650.1270.0190.000y二lpAxp1.0000.9130.7850.6130.3760.0720.000

由于泡點(diǎn)進(jìn)料q=l,在圖上作直線x=0.986交對(duì)角線于a點(diǎn)，作直線x=0.638交平衡線于q點(diǎn)，連接a、q兩點(diǎn)，過q點(diǎn)作橫軸的平行線交縱軸于一點(diǎn)，讀得圖1x—y圖y=0.896，則最小回流比如下：q0.986—0.896R——U.35min0.896-0.638取操作回流比為R—1.4R—1.4X0.35—0.49min求精餾塔的氣、液相負(fù)荷L—RD—0.49X47.31—23.18kmol/h—(R+1)D—(0.49+1)x47.31—70.49kmol/hL—L+F—23.18+73.24—96.42kmol/h—V—70.49kmol/h4）求操作線方程精餾段操作線方程TOC\o"1-5"\h\zLD23.1847.31y二x+x二x+x0.986二0.328x+0.662VVd70.4970.49提餾段操作線方程LW96422593y'二一x'-—x二x'-—9-x0.003二1.369x'-0.001V'V'—70.4970.49（5）圖解法求理論板層數(shù)如附圖1,將x=0.638帶入精餾段操作線方程，得出y=0.871,在圖中找出該點(diǎn)記為d,連接ad兩點(diǎn)即得精餾段操作線；在對(duì)角線上找到c點(diǎn)（0.003,0.003），連接cd兩點(diǎn)即得提餾段操作線。自a點(diǎn)開始在操作線和平衡線之間作階梯線。求解結(jié)果為：總理論板層數(shù)nt二11（包括再沸器）進(jìn)料板位置N二4F2．實(shí)際板層數(shù)的求解（試差法）假設(shè)總板效率E=0.49T精餾段實(shí)際板層數(shù)N蛀=22/0.49=44.9?45精提餾段實(shí)際板層數(shù)N曰二4/0.49-1二8.1-1沁7（不包括再沸器）提實(shí)際板層數(shù)為26/0.49-1=52（不包括再沸器）試差法計(jì)算如下：N=52p塔頂壓力：P二101.3+4二105.3KPaD塔底壓力.Pw=105.3+0.667x52=139.984Pa已知塔底組成為

四、精餾塔的工藝條件及有關(guān)物性數(shù)據(jù)的計(jì)算1．操作壓力的計(jì)算塔頂操作壓力P=101.3+4=105.33kPaD每層塔板壓降A(chǔ)P=0.7kPa進(jìn)料板壓力P=105.33+0.7x9=111.63kPaF精餾段平均壓力P=(111.63+105.33)/2=108.48kPam1塔底操作壓力P=105.33+0.7x23=121.43kPaD提餾段平均壓力P=(111.63+121.43)/2=116.53kPam22．操作溫度的計(jì)算表1苯、氯苯Antoine常數(shù)數(shù)據(jù)表ABC溫度圍（K）苯6.019071204.682-53.072279-3776.068321236.034-48.99353-4226.36071466.083-15.44420-521氯苯6.104161431.83-55.515335-4056.629881897.415.21405-597表1苯、氯苯Antoine常數(shù)數(shù)據(jù)表ABC溫度圍（K）苯6.019071204.682-53.072279-3776.068321236.034-48.99353-4226.36071466.083-15.44420-521氯苯6.104161431.83-55.515335-4056.629881897.415.21405-597假設(shè)塔頂?shù)呐蔹c(diǎn)溫度t=83.2oC,則純組分的飽和蒸氣壓為'亠lgpo=6.06832=2.04742對(duì)苯a-48.99+83.2+273.15po=111.53kPaA對(duì)氯苯lgpBo對(duì)氯苯lgpBo=6.10416-1431.83-55.515+83.2+273.15=1.34464po=22.11kPaBp-p-pox=Bpo-poAB=0.931代入泡點(diǎn)方程和露點(diǎn)方程，得(101.33+4)-22.11111.53—22.11111.53x0.931105.33=0.986=故假設(shè)正確，塔頂溫度為t二83.2oCD假設(shè)塔頂?shù)倪M(jìn)料板溫度t=94.4oC，則純組分的飽和蒸氣壓為lgpo=6.06832:=2.18825對(duì)苯a-48.99+94.4+273.15po=154.26kPa1431.83A1431.83lgpo=6.10416=1.51548對(duì)氯苯b-55.515+94.4+273.15po=32.77kPaB代入泡點(diǎn)方程和露點(diǎn)方程，得p—p—poX=Bpo-poAB鑒揺=0.638假設(shè)正確，故進(jìn)料板溫度為t=94.4oCF假設(shè)塔底的泡點(diǎn)溫度t=137oC，則純組分的飽和蒸氣壓為lgpo=6.06832一一對(duì)苯a-48.99+137+273.15對(duì)苯po=442.51kPaA對(duì)氯苯lgpB對(duì)氯苯lgpBo=6.62988-1897.415.21+137+273.15po=115.28kPaB代入泡點(diǎn)方程，得p一pp一poX=Bpo-poAB116.53一115.28442.51-115.28=0.0038沁0.003假設(shè)正確，故塔頂溫度為t=137oC精餾段平均溫度W精餾段平均溫度t=(83.2+94.4)/2=88.8oCm1

提餾段平均溫度t二(94.4+137)/2二115.7°Cm2全塔平均溫度t二(83.2+137)/2二llO.loCm3．平均摩爾質(zhì)量的計(jì)算塔頂：由y二x二0.986，查平衡曲線得x二0.9201D1M二0.986x78.11+(1-0.986)x112.56二78.60kg/kmolVDmM二0.920x78.11+(1-0.920)x112.56二80.87kg/kmolLDm進(jìn)料板：由圖理論板得y=0.885,查平衡曲線得x=0.621FFM二0.885x78.11+(1-0.885)x112.56二82.07kg/kmolVFmM二0.621x78.11+(1-0.621)x112.56二91.17kg/kmolLFm塔底：由圖理論板得y二0.003，查平衡曲線得x二0.001nnM=0.003x78.11+(1-0.003)x112.56二112.46kg/kmolVWmM二0.001x78.11+(1-0.001)x112.56二112.53kg/kmolLWm精餾段平均摩爾質(zhì)量M二(78.60+82.07)/2二80.34kg/kmolVm1M=(80.87+91.17)/2二86.02kg/kmolLm1提餾段平均摩爾質(zhì)量M二(82.07+112.46)/2二97.27kg/kmolVm2M二(91.17+112.53)/2二101.85kg/kmolLm24．平均密度的計(jì)算(1)氣相平均密度計(jì)算由理想氣體狀態(tài)方程計(jì)算，得精餾段pMp—m1Vm1Vm1精餾段pMp—m1Vm1Vm1RTm1108.48x80.348.314x(88.8+273.15)—2.90kg/m3提餾段pMp—m2Vm2Vm2RTm2116.53x97.278.314x(115.7+273.15)—3.51kg/m32）液相平均密度計(jì)算1w—乙一i-ppLmi

塔頂t=83.2oC時(shí),Dp二912-1.187x83.2二813.24kg/m3Ap二1127-1.111x83.2二1034.56kg/m3BpLDmpLDm=0.98/813.24+0.02/1034.56=816.73kg/m3進(jìn)料板t=94.4oC時(shí),FpApB二pApB二912-1.187x94.4二799.95kg/m3二1127-1.111x94.4二1022.12kg/m30.621x78.11pLFm==0.5320.621x78.11+0.379x112.561=0.532/803.7+0.468/1025.7=894.28kg/m‘塔底t二137oC時(shí),Wp=912-1.187x137=749.38kg/m3Ap=1127-1.111x137=974.79kg/m3BpLWm=0.002/749.38pLWm=0.002/749.38+0.998/974.79=974.20kg/m3精餾段液相平均密度為p=(816.73+894.28)/2=855.51kg/m3Lm1提餾段液相平均密度為p=(894.28+974.20)/2=934.24kg/m3Lm25．液相平均表面力的計(jì)算Q=YxQLmii塔頂t=83.2oC時(shí)，查得q=20.82mN/mQ=25.84mN/mDABQ=0.920x20.82+0.08x25.84=21.22mN/mLDm進(jìn)料板t=94.4oC時(shí)，查得q=19.35mN/mQ=24.57mN/mFABQ=0.621x19.35+0.379x24.57=21.32mN/mLFm塔底t=137oC時(shí)，查得q=14.25mN/mq=19.48mN/mWABb二0.001X14.25+0.999x19.48二19.47mN/mLWm精餾段液相平均表面力為b二(21.22+21.32)/2二21.27mN/mm1提餾段液相平均表面力為b二(21.32+19.47)/2二20.40mN/mm26.液體平均粘度計(jì)算lgp=丫xlgpmii塔頂t二83.2oC時(shí)，Dp=0.299mPa?sp=0.303mPa?sABlgp二0.920lg0.299+0.08lg0.303LDmp-0.299mPa?sLDm進(jìn)料板t二94.4oC時(shí)，F(xiàn)p=0.268mPa?sp=0.275mPa?sABlgp=0.621lg0.268+0.379lg0.275LDmp=0.271mPa?sLDm塔底t=137oC時(shí)，Wp=0.184mPa?sp=0.197mPa?sABlgp=0.001lg0.184+0.999lg0.197LDmp=0.197mPa?sLDm精餾段液相平均粘度為p=(0.299+0.271)/2=0.285mN/mm1提留段液相平均粘度為p=(0.271+0.197)/2=0.234mN/mm2II20丿全塔液相平均粘度為r二(0.299+0.197)/2二0.248mPa-sL又塔頂和塔底平均溫度為(83.2+137)/2=110」C則此溫度下的相對(duì)揮發(fā)度為?二紅二2347二4.40po53.3B根據(jù)奧康奈爾關(guān)聯(lián)法，E=0.49(仲)-0.245二0.49x(4.40x0.248)-0.245二0.48TL故假設(shè)成立，總板效率ET=0.48五、塔體工藝尺寸計(jì)算1．塔徑的計(jì)算(1)精餾段VM=vmi—VM=vmi—S13600pVm1LMI」—Lml—S13600pLm170.49x80.343600x2.9023.18x86.023600x855.1—0.542m3/s—0.0006m3/s由umax式中C由公式C—C由umax式中C由公式C—C0.2計(jì)算，其中C20可由史密斯關(guān)聯(lián)圖查出圖的橫坐標(biāo)為L(zhǎng)——h-V,p0.0006x3600(855.51\x0.541x3600I2.90丿12—0.019取板間距H—0.42m，板上液層高度h—0.07m，則TLH—h—0.42—0.07—0.35mTL由史密斯關(guān)系圖得C20—0.069(21.27\a2(b)0.2—L20120丿855.51—2.90u—0.070x—1.20m/smax—0.069x—0.0702.90TT44取安全系數(shù)為0.6，則空塔氣速為0.6u二0.72m/smax'4V兀u1:^054L=0.979m3.14x0.72統(tǒng)一按照《塔板結(jié)構(gòu)參數(shù)系列化標(biāo)準(zhǔn)（單溢流型）》將塔徑圓整后取D=1.0m。塔截面積兀314A二一D2二X1.02二0.785m2T44實(shí)際空塔氣速u=0.542=0.690m/s0.7852）提餾段V=S2LS2VMVm2—3600pVm2LM96.42x101.85nnnQQ,Lmi==0.0029m3/s3600p3600x934.24Lm2=4**7°.49x97.27=0.543m3/s3600x3.51P、VF丿

hVH—h=0.42—0.07=0.35mTL0.0029x3600(934.24\0.543x3600<3.51丿12=0.087查圖得（20二0.068(C)02—<20.40]C—m21=0.068x20I20丿〔20丿C=0.2=0.0683.51u=0.6u=0.6x1.12=0.67m/s3.51u=0.6u=0.6x1.12=0.67m/s2max■4V塔截面積max塔截面積33實(shí)際空塔氣速0.543u實(shí)際空塔氣速0.543u=0.785=0.692m/s2．塔高的計(jì)算(1)精餾塔的有效高度精餾段Z=(N—1)H=(9—1)x0.42=3.36m精精T提餾段Z=(N—1)H=(14—1)x0.4=5.46m提提T在進(jìn)料板上方開一人孔，提餾段中開兩個(gè)人孔，其高度為0?8m,則有效高度為Z=Z+Z+0.8x3=3.36+5.46+2.4=11.2m有效精提(2)全塔實(shí)際高度取進(jìn)料板板間距為0?8m,人孔處的板間距為0.8m，塔底空間高度為2.0m,塔頂空間高度為0?7m,封頭高度為0.6m，裙座高度為2.0m，則全塔高為H=(n—n—n—1)H+nH+nH+H+H+H+HFPTFFPPDB12=(23—1—3—1)x0.42+0.8+3x0.8+0.7+2.0+0.6+2.0=16.06m六、塔板主要工藝尺寸計(jì)算根據(jù)塔徑和液體流量，選用單溢流弓形降液管、凹形受液盤，塔板采用單流和分塊式組裝。1)堰長(zhǎng)：2)堰高：1．溢流裝置的計(jì)算l=0.66D=0.66x1)堰長(zhǎng)：2)堰高：由h=h—h，選用平直堰，堰上液層高度由弗蘭西斯公式求得WLOW精餾段：h竺EOW1精餾段：h竺EOW110002.84(0.0006x3600、210000.66丿3=0.00626m取h二0.07m，則LhW1二h-h二0.07-0.00626二0.06374mLOW1提餾段：hOW22.84E1000IlL)4h2w丿取h二0.07m，則LhW1二h-h二0.07-0.00626二0.06374mLOW1提餾段：hOW22.84E1000IlL)4h2w丿2.84(0.0029x3600\100010.66丿23=0.0018mh二h-h二0.07-0.018二0.052mW2LOW2（3）降液管面積當(dāng)Iw=0.66時(shí)，查表得d=0.124,W=0.124x1.0=0.124mDdAf=0.0722,A=0.0722x0.785=0.057m2AfT塔的相對(duì)操作面積為G-2x0.0715)x100%=85.7%4）液體在降液管里停留的時(shí)間精餾段3600AH9二f—T1Lh13600x0.057x0.40—38s>5s3600x0.0006故降液管設(shè)計(jì)合理（5）降液管底隙高度h0h—0Lh—36001u'w0精餾段和提餾段降液管下端與塔板間出口處的液體流速分別取u'—0.075m/s01u'—0.180m/s02精餾段01Lhi—3600/u'w013600x0.00063600x0.66x0.075—0.012m提餾段h02L36001u'w023600x0.00293600x0.66x0.180—0.024m2．塔板布置的計(jì)算選用Fl型浮閥，閥孔直徑39mm，閥片直徑48mm，閥片厚度2mm，最大開度8.5mm，靜止開度2.5mm，閥質(zhì)量為32~34g。1）閥孔臨界速度精餾段lu]0Kp1(72.8)°.548'72.8￥精餾段lu]0Kp1(72.8)°.548'72.8￥548.290丿二5.86m/s提餾段lu]0Kp2(728)0.548〔叮丿(72.8\0.548、351丿-5.27m/s上下兩段相應(yīng)的閥孔動(dòng)能因子為：F=\u]j廠-5.86上下兩段相應(yīng)的閥孔動(dòng)能因子為：F=\u]j廠-5.86迂麗-9.979010_Kp1^V1F-\u]、芮-5.27.331-9.873020Kp2'V2均屬正常操作圍。取邊緣區(qū)寬度W=0.055m,安定區(qū)寬度W-0.065m,cs開孔區(qū)面積C，二兀R2.x-2xvR2—x2+sin-1一180Rn211-2°.31山4452—°3112+盒x0.4452sin-1扇-0?504m2其中，R-——W-10—0.055-0.445m2C2x-D—(W+W)=10—(0.124+0.065)=0.3112ds22）提餾段塔板布置取邊緣區(qū)寬度W=0.030m,安定區(qū)寬度W-0.055m,cs開孔區(qū)面積X\R2—X\R2—x2+nR2180xsin—1-RQOQ1=20?321J。4702-0?3212+命x0?4702sin—1苗=0-552m2其中，R二—-W二1.0-0.030二0.470m2C2x=D-(W+W)=10-(0.124+0.055)=0.3212ds2(3)浮閥數(shù)n與開孔率申F1型浮閥的閥孔直徑為39mmF閥孔氣速u0=L，其中取F=10

"VV浮閥數(shù)目n=u0d2兀/400d2=n-0-—2精餾段10un==5.87m/s0<2.904x0.542n==785.87x0.039x0.039x代0.039x0.0399=78x=11.86%1.x1提留段u0=10=5.34m/s0<3.514x0.543n==865.34x0.039x0.039x3.140.039x0.0399=86x=12.94%1x1浮閥排列方式采用等腰三角形叉排，取同一橫排的孔心距t=0.075m,則排間距tf為A0.504精餾段t=a==0.0862m=86.2mmnt78x0.075A0.552提留段t'=a==0.0856m=86.6mmnt86x0.075考慮到塔的直徑較大，故采用分塊式塔板，而各分快板的支撐與銜接將占去一部分鼓泡區(qū)面精餾段n=Aa=°.504=84tt'0.075x0.08積，因此排間距應(yīng)小于計(jì)算值，故取t'=80mm=0.08m重新計(jì)算孔速及閥數(shù)VV0.542x4u===5.53m/s0nd2兀/484x0.039x0.039x3.140F0二5.53x、；290二9.41申=84x0.039x0.039=12.78%1x1Aa0.552提留段n=a==92tt'0.075x0.080.543x4u===4.94m/s0nd2兀/492x0.039x0.039x3.140F0二4.94xf331二9.25一92xO.。39xO.。39=13.99%1x1由此可知，閥孔動(dòng)能因數(shù)變化不大七、塔板流體力學(xué)驗(yàn)算1．塔板壓降h二h+h+hpcib1）干板阻力精餾段u=i8/73.1/p=i.82§''73.1/2.90=5.860m/s0c1V1u<u,則010c1u0.17519x5.530.175h=19.001==0.029m液柱clP855.51L1提餾段u0c2=1^；73.1/p=1.82573.1/3.51=5.27m/sV2<u,則

0c2u0.175=19.0pL22）板上充氣液層阻力u02hc2=葺晉=0.026m液柱取充氣系數(shù)s=0.5,則0=sh=0.5x0.07=0.035m液柱0L3）液體表面力所造成的阻力：此阻力很小，忽略不計(jì)。因此，上下兩段塔板壓降如下精餾段每層壓降h=h+h=0.029+0.035=0.064m液柱p1c1lAp=hpg=0.064x855.51x9.81=537.12Pa<700Pap1p1L1提餾段每層壓降h=h+h=0.026+0.035=0.061m液柱p2c2lAp=hpg=0.061x934.24x9.81=559.06Pa<700Pap2p2L2上下兩段單板壓降均符合設(shè)計(jì)任務(wù)要求。2．液泛為了防止液泛現(xiàn)象的發(fā)生，要求控制降液管中清液層高度H（H+h）,dTW而H二h+h+hdpLd（1）與氣體通過塔板壓降所相當(dāng)?shù)囊褐叨忍狃s段(L\2(―S^=提餾段(L\2(―S^=0.153W01精餾段h=0.153d10.0006]0.66x0.012丿2=0.00088m液柱fL)2fh=0.153ccS2=0.153d2k1h丿W02k0.0029]0.66x0.024丿=0.0051m液柱精餾段h=0.064m液柱p1提餾段h=0.061m液柱p22）液體通過降液管的壓頭損失3）板上液層高度精餾段和提餾段皆為h=0.07mL因此，取0=0.5，降液管中清液層高度如下:精餾段H=h+h+h=0.064+0.070+0.00088=0.1349md1p1L1d10(H+h)=0.5(0.42+0.06374)=0.2419>HTW1d1可見，精餾段符合防止液泛的要求。提餾段H=h+h+h=0.061+0.07+0.0051=0.136md2p2L2d20(H+h)=0.5(0.42+0.052)=0.236>HTW2d2

可見，提餾段符合防止液泛的要求。3．液沫夾帶(1)精餾段液沫夾帶量e的驗(yàn)算v5.7xl0-6i竹-hf丿5.7xlO-5.7xlO-6(0.744521.27x10-30.42—2.5x0.07>3.2丿=0.0094kg液/kg氣<0.1kg液/kg氣故在設(shè)計(jì)負(fù)荷下不會(huì)發(fā)生過量液沫夾帶。(2)故在設(shè)計(jì)負(fù)荷下不會(huì)發(fā)生過量液沫夾帶。(2)提餾段液沫夾帶量e的驗(yàn)算v5.7x10-6c5.7x10-6c(u>3.25.7x10-6(0.7458>3.2厲-hf丿20.40x10-3J0.42—2.5x0.07丿=0.0085kg液/kg氣<0.1kg液/kg氣故在設(shè)計(jì)負(fù)荷下不會(huì)發(fā)生過量液沫夾帶。4故在設(shè)計(jì)負(fù)荷下不會(huì)發(fā)生過量液沫夾帶。4．漏液的驗(yàn)算(1)精餾段漏液的驗(yàn)算Fu0=取F『5,則PV<2.90=<2.90=2.94m/s<5.53m/s故在設(shè)計(jì)負(fù)荷下不會(huì)產(chǎn)生過量漏液。(2)提餾段漏液的驗(yàn)算=故在設(shè)計(jì)負(fù)荷下不會(huì)產(chǎn)生過量漏液。(2)提餾段漏液的驗(yàn)算==2.67m/s<4.94m/s0J3.51故在設(shè)計(jì)負(fù)荷下不會(huì)產(chǎn)生過量漏液。八、塔板負(fù)荷性能圖計(jì)算(一)精餾段塔板負(fù)荷性能圖1、漏液線0F0取F0=5，兀兀故(V).=一d2nm=—x0.0392x840F0取F0=5，兀兀故(V).=一d2nm=—x0.0392x84x2.94=0.295m3/ssmin4004據(jù)此做出與液體流量無關(guān)的水平漏液線(1)2．液沫夾帶線5.7x10-6ev(、

utH-h丿Tf3.2其中，ua=HT=0.785丿0.057=0.746VSTfa)h=2.5^fw+h)=2.5owh+2.84x10-3Ew3600L)近似取E~1.0,h=0.06374m,l=0.66mwWh=2.50.06374+2.84x10-3x1.0x(3600LSj0.66丿丿=0.159+2.20L2/3(b)S取液沫夾帶極限值e為0.1kg液/kg氣。v已知b=21.7mN/m,H=0.42mT并將(a)(b)代入得：0.1=x100.1=x10-6x10-30.746VI0.42—0.159—2.2L2/3SA3.2丿整理得：V=2.23-18.87L2/3SS在操作圍任取幾個(gè)L值，依上式算出相應(yīng)的V值列于下表中SSL,m3/ss0.00060.00150.00300.0045V,m3/ss2.101.981.841.72依表中數(shù)據(jù)在V—L圖中作出液沫夾帶線(2)。SS3．液相負(fù)荷下限線取平堰、堰上液層高度h=0.006m作為液相負(fù)荷下限條件，取E沁1.0ow2.843600L則h=E(Sn)2/3ow1000lw2.840.006=—xl.Ox1000(3600LS:min、0.66丿整理上式得L=0.00056m3/ss,min4．依此值在V—L圖中作線即為液相負(fù)荷下限線（3）。SS液相負(fù)荷上限線(L)=化=°.°57xO.42=0.006m3/sSmax445．依此值在V—L圖中作線即為液相負(fù)荷上限線（4）SS液泛線令H=9(H+h)dTWH=h+h+h;h=h+h+h;h=ph;h=h+hdpLdpc1匕1LLwow聯(lián)立整理得aV2=b—cL—dLs230.051式中a=將牛）=麗鶉顧（諾）=0.029ooLb=9H+(9—P—1)h=0.5x0.42+(0.5—0.60—1)x0.06374=0.140TWc=°.153/(lwho)2=(0.6比012)2=2439d=2.84x10-3E(1+p)(3600)23=2.84x10-3(1+0.60)(3600)23=1.40l0.66w故0.029V2=0.14—2439L—1.40L23sssL,m3/ss0.00060.00150.00300.0045V,m3/ss4.794.013.071.81在操作圍任取幾個(gè)L，計(jì)算出V的值列于表中。SS依此值在V—L圖中作線即為液泛線（5）SS將以上5條線標(biāo)繪于V-L圖中，即為精餾段負(fù)荷性能圖。5條線包圍區(qū)SS域?yàn)榫s段塔板操作區(qū)，A為操作點(diǎn)，0A為操作線。0A線與（2）線的交點(diǎn)相應(yīng)相負(fù)荷為V，0A線與氣相負(fù)荷下限線（1）的交點(diǎn)相應(yīng)氣相負(fù)荷為VS,maxs,min。圖見坐標(biāo)紙。可知本設(shè)計(jì)塔板上限由液沫夾帶控制，下限由漏液控制。讀圖，精餾段的操作彈性—S‘max==4V0.42S,min二、提餾段塔板負(fù)荷性能圖1、液沫夾帶線（1）5.7x10-6式中utH-h丿Tf3.2nn=1.374VA-A0.785-0.057sTa)=2.5^+hwow2.5h+2.84x10-3Ew3600L)l丿W丿近似取E~1.0,h=0.052m,l=0.66mwW故h=2.50.052故h=2.50.052+2.84x10-3x1.0x(3600L)SV0.66丿二0.13+2.2L2/3Sb)取液沫夾帶極限值e取液沫夾帶極限值e為0.1kg液/kg氣。已知b=20.40x10-3N/m，vH=0.42mT0.1=5.7x0.1=5.7x10-620.40x10-31.374VxsV0.42—0.13—2.2L2/3sA3.2丿整理得：V=1.36—10.1L2/3ss在操作圍任取幾個(gè)仝值’依上式算出相應(yīng)的VS值列于下表中L3/sS，m0.00060.00150.0030.0045V3/sS,m1.291.231.151.08依表中數(shù)據(jù)在VS—LS圖中作出液沫夾帶線（1）。2、液泛線（2）由H=h+h+h和H<①(H+h)得dpLddTw0+h)=h+h+h+h，Twpwowd近似取E沁1.0，l=0.66mwh=2.84x10-3Eowh=h=2.84x10-3Eowh=0.051c=2.84x10-3x1.0x=0.051xrvICA丿00、2Px—PL(3600L)S0.66丿2323=0.88L3sv5l丿2x3.51=0.032V2934.24sVS

r0.772x0.100丿=eC+h)=0.73x().052+0.88L2/3)=0.038+0.6424L2/30wow2S=0.051pSrl\2pSrl\2Srl\h=0.153―1=0.153Sdd丿、0.66x0.024丿w將HT2=609.79L2S=0.0018m（已算出），故h=0.032V2+0.038+0.6424L篤+0.0018=0.032V2+0.6424L2/3+0.0398SS0.42m，h=0.052m,0=0.5及以上各式代入得W0.5(0.42+0.052)=0.032V2+0.0398+0.6424L2/3+0.052+0.88L2/3+609.79L2SSSS整理得V2=4.51-47.58L2/3-19056.0L2SSS在操作圍任取幾個(gè)LS值’依上式計(jì)算Vs值列于下表中L3/s0.00060.00150.0030.0045S，m

V3/s2.041.971.831.68S,m依表中數(shù)據(jù)在VS—LS圖中作出液泛線⑵。3、液相負(fù)荷上限線（3）取液體在降液管中停留時(shí)間為4秒，由下式LSmaxHLSmaxH-A―T——fT0.42x0.0574=0.00599m3/s液相負(fù)荷上限線⑶在VS—LS圖中為與氣相流量Vs無關(guān)的垂線。4、漏液線（氣相負(fù)荷下限線）（4）F0VU=0—u0V取F-5，又n一0u0d2兀/400兀兀故（V）.=一d2nu°=一x00392x92x2.67=0.293m3/ssmin4004據(jù)此做出與液體流量無關(guān)的水平漏液線（1）5、液相負(fù)荷下限線（5）取平堰、堰上液層髙度h=0.006m作為液相負(fù)荷下限條件，取E1.0ow2.843600Lh=E(jin)2/3ow1000l(3600LS(3600LS,min0.66丿2.840.006=—x1.0x1000整理上式得L=5.63x10-4m3/ss,min依此值在Vs—Ls圖中作線即為液相負(fù)荷下限線（5）。將以上5條線標(biāo)繪于V-L圖中，即為提餾段負(fù)荷性能圖。5條線包圍區(qū)域?yàn)樘狃s段SS塔板操作區(qū)，P為操作點(diǎn)，0P為操作線。0P線與（2）線的交點(diǎn)相應(yīng)相負(fù)荷為V,OPS,max線與氣相負(fù)荷下限線（4）的交點(diǎn)相應(yīng)氣相負(fù)荷為V。圖見坐標(biāo)紙。s,min可知本設(shè)計(jì)塔板上限由液泛控制，下限由漏液控制。TOC\o"1-5"\h\z1.42讀圖，提餾段的操作彈性=?噸==3.380.42S,min九、精餾塔接管尺寸計(jì)算LWmLWm1．塔頂蒸氣出口管“VRT70.49x8.314x(83.2+273.15)門「廠/V二—二二0.551m3/sS3600p3600X105.33D選擇蒸氣速度u=18m/s，則i'4Vdi'4Vd二牯二，土也二0.197mY3.14x18按照按照GB8163—87，選擇熱軋無縫鋼管0245x6.5mm核算u==4X0.551=11.69m/s，在10~20m/s之間，可用。兀d23.14x0.24522．塔頂回流液管LMI」LMI」—LDmS3600pLDm35.5x80.183600x823.81=0.001m3/s選擇回流液流速u=0.4m/s選擇回流液流速u=0.4m/s，則:4xO.。006—0.043m3.14x0.4按照GB8163—87，選擇冷軋無縫鋼管045x2mm核算U呂=卅需=0.377m/s，在0.2?°.5m/s之間’可用。3．進(jìn)料管FMF—FMF—LFmS3600pLFm73.24x91.173600x894.28=0.0021m3/s選擇進(jìn)料液流速選擇進(jìn)料液流速u=2.0m/s，則d=d=丐='-0.037m3.14x2.0按照按照GB8163—87，選擇冷軋無縫鋼管042x2mm4F4x0.0021核算u—&——1.52m/s，在1.5?2.5m/s之間，可用。兀d23.14x0.04224．塔釜出料管,LM—,LM—LWm—S3600p96.42x112.533600x974.20—0.0031m3/s選擇塔釜出料液流速u=0.8m/s，則i^L^i'4i^L^i'4x0.0034d⑴二V3.14X0.8二°.°71m按照GB8163—87，選擇冷軋無縫鋼管Q83x2mm4L4x0.00309核算u=s==0.57m/s，在0.5~1.0m/s之間，可用。兀d23.14x0.08325．加熱蒸氣進(jìn)口管=1.26=1.26〉1.15選擇蒸氣速度u=選擇蒸氣速度u=15m/s，則VRT_70.49x8.314x(137+273.15)w——3600pw3600X116.53=0.573m3/sd—、：竺d—、：竺：4x0.747\：3.14x15=0.22m按照GB8163—87，選擇熱軋無縫鋼管0245x12mm4V'4X0747核算u—―s—.—12.3m/s，在12~20m/s之間，可用。兀d23.14x0.2452十產(chǎn)品冷卻器選型基本物性數(shù)據(jù)的查取:塔頂氯苯含量較少，可按純苯求取苯的定性溫度t=83.2°CD設(shè)水的進(jìn)口溫度為\—25C根據(jù)設(shè)計(jì)經(jīng)驗(yàn)，選擇冷卻水的溫升為8C,則水的出口溫度為t2—25+8—33C水的定性溫度25+33—29C2查得苯在定性溫度下的物性數(shù)據(jù)密度：P—812.94kg/m3飽和蒸汽氣化熱：r=393.9kJ/kg查得水在定性溫度下的物性數(shù)據(jù)密度：P—995.5kg/m3

定壓比熱容：C二4.174kJ/(kg?°C)p導(dǎo)熱系數(shù)：k=0.618W/(m2??黏度：卩=0.80X10一3Pa?s②熱負(fù)荷計(jì)算:Q二M?D?r=78.11X47.31X393.9X103/3600=4.04X105W4.04x4.04x105W===12.11kg/scC(t-t)4.174x10333-25)pc21確定流體的流徑該設(shè)計(jì)任務(wù)的熱流體為苯，冷流體為水，為使苯能通過殼壁面向空氣中散熱,提高冷卻效果，令苯走殼程，水走管程.計(jì)算平均溫度:暫按單殼程、雙管程考慮，先求逆流時(shí)平均溫度差苯T冷卻水t83.283.23325苯T冷卻水t83.283.23325△t50.258.2=At2~At1=58m2=54.10C

,At.58.2In2InAt50.21計(jì)算R和P：T-T-TR二2二0

t-t21t-t二0.137查表得：0查表得：0二1,At因0>0.&選單殼程可行。AtAtAt'二54.10CmAtm選擇換熱器型號(hào)由于兩流體溫差~50C，殼選用固定管板式換熱器的系列標(biāo)準(zhǔn)(JB/T4715-92)選擇主要參數(shù)如下：公稱直徑dn400mm公稱壓力公稱直徑dn400mm公稱壓力Np1.6MPA管程數(shù)NP4管子尺寸025x2.5管子根數(shù)n94管長(zhǎng)6000mm管中心距32mm中心排管數(shù)11管子排列方式正三角形管程流通面積0.0163m2實(shí)際換熱面積S0=n兀d(L一0.1)0=94x3.14x0.025(6-0.1)=43.5m2選K值，估算傳熱面積參照《化工流體流動(dòng)與傳熱》附錄二十六，初選取K=310W/(m2?*)QKAQKAtm4.04x105310x54.10=24.1m2435-230安全系數(shù)：F-x100%=891%，傳熱面積的裕度可滿足工藝要求。安全系數(shù)：采用此換熱面積的換熱器，則要求過程的總傳熱系數(shù)為：K=—Q=4.04x105=172W/(m2??0SAt43.5x54.100m驗(yàn)算：K\K=310172=1.80>1.15，符合實(shí)際標(biāo)準(zhǔn)o、設(shè)計(jì)結(jié)果一覽表物料衡算結(jié)果序號(hào)項(xiàng)目符號(hào)單位數(shù)值備注1塔頂摩爾分?jǐn)?shù)xD10.9862塔頂平均摩爾質(zhì)量MDkg/kmol78.6080.87氣相液相3塔頂流量Dkmol/h45.074進(jìn)料摩爾分?jǐn)?shù)xF10.6385進(jìn)料液平均摩爾質(zhì)量MFkg/kmol82.0791.17氣相液相6進(jìn)料流量Fkmol/h73.24

7塔釜摩爾分?jǐn)?shù)xW10.0038塔釜平均摩爾質(zhì)量MWkmol/h112.46氣相112.53液相9塔釜產(chǎn)品流量W25.93精餾塔工藝條件及有關(guān)物性數(shù)據(jù)計(jì)算結(jié)果序號(hào)項(xiàng)目符號(hào)單位精餾段提餾段備注1每層塔板壓降A(chǔ)pkPa0.7E二0.48T2平均壓力PmkPa108.48116.533平均溫度tmoC88.8115.74平均粘度mmPa-s0.2860.2355液相平均摩爾