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1、设计计算设计方案的确定本设计任务为分离甲醇-水混合物。对于二元混合物的分离，应采用连续精馏流程。设计中采用泡点进料，将原料液通过预加热器至泡点后送入精馏塔内。塔顶上升蒸汽采用全凝器冷凝，冷凝液在泡点下一部分回流至塔内，其余部分经产品冷却器冷却后送至储罐。该物系属易分离系，最小回流比，故操作回流比取最小回流比的2倍。塔釜采用间接蒸汽加热，塔底产品经冷却后送至储罐。精馏塔的物料衡算1、原料液及塔顶、塔底产品的摩尔分率甲醇的摩尔质量 M甲醇=32.04kg/ kmol 水的摩尔质量 M水=18.02kg/kmolXF= XD=XW=2、原料液及塔顶、塔底产品的平均摩尔质量MF=0.27332.04+
2、（10.273）18.02=21.85kg/kmolMD=0.994732.04+(10.9947）18.02=31.96kg/kmolMW=0.00281832.04+(10.002818)18.02=18.06kg/kmol3、物料衡算原料处理量：F=kmol/h总物料衡算：F=D+W 115.57=D+W甲醇物料衡算：FXF=DXD+WXW 115.570.273=D0.9947+W0.002818联立解得 D=31.48kmol/h w=84.09kmol/h塔板数的确定1、理论板数的求取由 y=及甲醇水在不同温度下的汽液平衡组成温度液相气相a温度液相气相a92.90.05310.28
3、347.0581.60.20830.62736.490.30.07670.40018.0380.20.23190.64856.1188.90.09260.43537.55780.28180.67755.3586.60.12570.48316.577.80.29090.68015.18850.13150.54557.9376.70.33330.69184.4983.20.16740.55866.2976.20.35130.73475.1182.30.18180.57756.1573.80.4620.77564.0272.70.52920.79713.49680.77010.89622.5771.
4、30.59370.81833.0866.90.87410.91941.64700.68490.84922.59am=4.83得到相平衡方程 y=因为泡点进料，所以q=1 且Xq=XF=0.273且q点过相平衡线 则yq=0.645Rmin=0.94 取操作回流比 2、 求精馏塔的气液相负荷1.8831.48=59.18kmol/h V=(R+1)D =2.8831.48=90.66kmol/h =L+F=59.18+115.57=174.75kmol/h =V=90.66kmol/h3、 求操作线方程精馏段操作线方程 =+=0.6528Xn+0.3454提馏段操作线方程 =1.927Xn-2.
5、61410-35、逐板计算法求理论板数因为塔顶为全凝器 通过相平衡方程求 X1=再通过精馏段操作线方程 y2=0.6528X1+0.3454=0.9818 ，如此反复得y1=0.99947x1=0.9749y2=0.9818x2=0.9179y3=0.9446x3=0.7793y4=0.8541x4=0.5482y5=0.7032x5=0.3291y6=0.5603x6=0.20870.273当X6Xq后，改用相平衡方程与提馏段操作方程yn+1=1.927Xn-12.61410-3计算.如此反复得y7=0.3995x7=0.1211y8=0.2308x8=0.0585y9=0.1101x9=0
6、.025y10=0.0455x10=0.1474y11=0.02578x11=5.4510-3y12=7.8810-3x12=1.6410-30.002818可得到进料板位置 NF=6总理论板数 NT=12 2、实际板层数的求取精馏段实际板层数：N精=8.39提馏段实际板层数：N提=10（不包括再沸器）精馏塔工艺条件及有关物性数据的计算1、 操作压力计算塔顶操作压力 PD=101.3+4=105.3KPa每层塔板压力降 DP=0.7KPa进料板压力 PF=105.3+0.79=111.6KPa塔底压力 Pw=PF+0.710=118.6KPa精馏段平均压力 Pm=KPa提馏段平均压力 Pm=K
7、Pa2、 操作温度计算（内插法得）根据甲醇-水的气-液平衡组成表，再通过内插法得：塔顶温度 tD=64.79进料板温度 tF=78.3塔釜温度 tw=99.6精馏段平均温度 tm=提馏段平均温度 tm=3、 平均摩尔质量的计算塔顶平均摩尔质量计算由XD=y1=0.9947 通过相平衡方程求得 X1=0.9749MVDM=y1M甲+（1-y1）M水=0.994732.04+(1-0.9947) 18.02=31.97Kg/KmolMLOM=X1M甲+（1-X1）M水=0.974932.04+(1-0.9749) 18.02=31.69 Kg/Kmol进料板平均摩尔质量计算 通过逐板计算得进料板y
8、F=0.5603，再通过相平衡方程得XF=0.2087MVFM= yFM甲+（1-yF）M水=0.560332.04+（1-0.5603）18.02=25.87Kg/KmolMLFM=XFM甲+（1-XF）M水=0.208732.04+（1-0.208718.02）=20.95Kg/Kmol塔釜平均摩尔质量的计算由Xw=0.002818 查平衡曲线得 yw=0.01346MVWM=ywM甲+（1-yw）M水=0.0134632.04+（1-0.01346）18.02=18.21Kg/KmolMLWM=XWX甲+（1-XW）M水=0.00281832.04+（1-0.002818）18.02=1
9、8.06Kg/Kmol精馏段平均摩尔质量MVM=MLM=提馏段平均摩尔质量MVM=MLM=4、平均密度计算气相平均密度计算由理想气体状态方程计算 即精馏段 rVM= Kg/m提馏段 rvm= 液相平均密度计算液相平均密度按下式计算 即塔顶液相平均密度的计算 由tD=64.79 查手册得 r甲=747.168Kg/m r水=980.613Kg/mrLPM=Kg/m进料板液相平均密度计算 由tF=78.3 查手册得 r甲=735.53 Kg/m r水=972.82 Kg/m进料板液相的质量分率 rLFM=Kg/m提馏段液相平均密度计算 由tw=99.6 查手册得 r甲=716.36Kg/m r水=
10、958.176 Kg/mrLWM= Kg/m精馏段液相平均密度为rLM= Kg/m提馏段液相平均密度rLM=Kg/m5、液体平均表面张力的计算液相平均表面张力依下式计算 即 dLM=Xidi塔顶液相平均表面张力的计算 由tD=64.79查手册得d甲=18.31mN/m d水=65.29Mn/mdLOM=XDd甲+（1-XD）d水=0.994718.31+0.005365.29=18.56mN/m进料板液相平均表面张力的计算 由tF=78.3 查手册得 d甲=17.0647mN/m d水=62.889mN/mdLFM=XFd甲+（1-XF）d水=0.208717.0647+0.791362.88
11、9=53.32mN/m塔釜液相平均表面张力的计算 由tw=99.6 查手册得 d甲=14.93mN/m d水=58.9mN/mdLWM=Xwd甲+(1-Xw)d水=0.00281814.93+（1-0.2087）62.889=53.32mN/m精馏段液相平均表面张力为dLM=mN/m提馏段液相平均表面张力为dLM=mN/m6、液体平均粘度计算液相平均粘度以下式计算，即mLM=Ximi塔顶液相平均粘度计算 由tD=64.79查手册得m甲=0.3289mpa.s m水=0.4479mpa.smLDM=XDm甲+（1-XD）m水=0.9947g（0.3289）+（1-0.9947）（0.4479）=
12、 0.4825mLDM=0.3292mpa.s进料板液相平均粘度计算 由tF=78.3查手册得m甲=0.28193mpa.s m水=0.37084mpa.smLFM=XFm甲+（1-XF）m水=0.2087(0.28193)+(1-0.2087)(0.37084)=0.4557mLFM=0.35mpa.s由tw=99.6 查手册得m甲=0.226mpa.s m水=0.289mpa.smLWM=Xwm甲+(1-Xw)m水=0.002818lg(0.226)+(1-0.002818)(0.289)=-0.5394mLWM=0.2888mpa.s精馏段液相平均黏度为mLM=mpa.s提馏段液相平均黏
13、度为mLM=mpa.s精馏塔的塔体工艺尺寸计算1、 塔径的计算精馏段的气液相体积流率为Vs= m/sLs= m/s提馏段的气液相体积流率为Vs=m/sLs= 10-3 精馏段 umax= 式中C由C20求取，C20可通过查图（P129页）筛板塔的泛点关联图的横坐标功能参数取板间距HT=0.35m（通过筛板塔的的泛点关联图）（书P129 图10-42）得到C20=0.068C=C20（）0.2=0.068() 0.2=0.07646最大空塔气速umax=取安全系数为0.8，则空塔气速u=0.8umax=0.82.085=1.668m/sD=按标准塔径圆整后 D=0.8m（据书P129 表10-1
14、）塔截面积为AT=m实际空塔气速 u=(安全系数在允许范围内，符合设计要求)提馏段同理查阅得C20= =0.05161查表得 HT=0.35m C20=0.07C=C20()0.2=0.07()0.2=0.08602Umax=C=0.08602=2.84m/s同上取安全系数0.8 u=0.8 Umax=0.82.84=2.272m/sD=0.6076m 圆整取D=0.8m 同上AT=0.5024实际空塔气速u=（符合安全系数范围，设计合理）2、精馏塔有效高度的计算精馏段有效高度为Z精=（N精-1）HT=（9-1）0.35=2.8m提馏段有效高度为Z提=（N提-1）HT=（10-1）0.35=3
15、.15m在加料板上设一人孔，其高度为0.7m故精馏塔的有效高度为Z=Z精+Z提+0.7=2.8+3.15+0.7=6.65m塔板主要工艺尺寸的计算1、溢流装置计算因塔径D=0.8，可选用单溢流弓形降液管，采用凹形受液盘堰长lw 取lw=0.6D=0.48m溢流堰高度hw 由hw=hLhow选用平直堰，堰上液层高度how=取E=1.03 how=mm how=mm取板上清液高度为hL=60mm hw=60-7,35=0.05265m hw=60-11.31=0.04869m弓形降液管宽度wd和截面积Af由 查图（P127页 弓形降液管的宽度与面积图）得 所以Af=0.052AT=0.0520.5
16、024=0.02612Wd=0.1D=0.10.8=0.08m所以依式计算液体在降液管中的停留时间精馏段：q= 35s（故设计合理）提馏段：q= 35s(故设计合理)降液管低隙高度h。h。.= u。=0.08m/s精馏：h。=提馏：h。=故降液管设计合理，选用凹形受液盘hw=52.65mm hw=48.69mm2、塔板布置塔板的分块因D800mm,故塔板采用分块式，塔板查表可知分为3块边缘区宽度确定取Ws=Ws=0.04m wc=0.03m开孔区面积计算Aa=2（）x=(wd+ws)=R=wc=故Aa=2（0.28）=0.3703筛孔计算及其排列选用d=3mm碳钢板，取筛孔直径d。=4.5mm
17、筛孔按正三角形排列，取孔中心距t为 t=3.1d。=3,14.5=13.95mm筛孔数目n为 n=开孔率f=0.907（）2=0.907（）2=9.44%气体通过阀孔的气速精馏段 u。=提馏段 u。=(七)塔板的流体力学验算1、塔板压降干板阻力hc计算：（由查资料附表图3-14干筛孔的流量系数有C。=0.82）hc=液柱hc=液柱气体通过液层的阻力hl及hlua=F。= ua =1.4619/查资料附表图3-15充气系数关联图，由F。=1.4619 得b=0.59hc=bhL=b（hw+how）=0.59（0.05265+0.00735）=0.0354m液柱ua=F。= ua=/查资料附表图3
18、-15充气系数关联图，由F0=1.258得b=0.62hc=bhL=b（hw+how）=0.62液体表面张力的阻力hs及hs计算hs=hs=气体通过每层塔板的液柱高度hp及hp计算hp=hp=气体通过每层塔板的压降DPp及DPp计算DPp =（设计允许值）DPp=（设计允许值）2、 液面落差对于筛板塔，液面落差很小，且本方案的塔径和液流量均不大，故可忽略页面落差影响。3、液沫夹带液沫夹带量ev及ev计算按经验，一般hf=2.5hc=2.50.06=0.15mev=3.2=3.2=0.07986Kg液/Kg气0.1 Kg液/Kg气ev=3.2=3.2=0.0489 Kg液/Kg气稳定系数K=实际
19、孔速u。=18.73稳定系数K=5、液泛为防止塔内发生液泛，降液管内液层高Hd及Hd应服从下式Hdj（HT+hw） j取0.5；Hdj（HT+hw）j（HT+hw）=0.5（0.35+0.03882）=0.19441m液柱j（HT+hw）=0.5（0.35+0.04869）=0.199 m液柱而Hd=hp+hL+hd；Hd= hp+hL+hd板上不设进口堰hd=hd=hd=0.001m液柱Hd=hp+hL+hd=0.07629+0.06+0.001=0.13729m液柱0.19441m液柱Hd= hp+hL+hd=0.0669+0.06+0.001=0.1279 m液柱0.199m液柱故在本设
20、计中不会出现液泛现象（八）塔板负荷性能图1.漏液线由得同理可得在操作范围内，任取几个值，依上式计算出值，计算结果列于下表：Ls（Ls），0.00050.00100.00150.0020Vs，0.3400.3490.3570.364Vs，0.3340.3360.3380.340由上表数字即可作出漏液线2、液沫夹带线以=0.1液/气为限，求Vs-Ls关系如下由整理得同理可计算出整理得在操作范围内，任取几个Ls（Ls）值，依上式计算出Vs值，计算结果列于下表：Ls（Ls），0.00050.00100.00150.0020Vs，0.8620.8250.7930.766Vs，0.8640.8220.78
21、60.754由上表得出液沫夹带线3、液相负荷下限线对于平直堰，取液上液层高度how=0.006m，作为最小液体负荷标准，由下式得取E=1，则同理，据此作出气体流量无关的垂直液相负荷下限图4、液相负荷上限图以=4s作为液体在降液管中停留时间的下线，由下式得故据此可以作出与气体流量无关的垂直液相负荷上限图5、液泛线令由式中，故在操作范围内，任取几个值，依上式计算出值，计算结果列于下表0.00050.00100.00150.00201.2211.1861.1451.0951.3801.3321.2861.240由上表数据即可作出液泛线（5）换热器的设计1、冷凝器的选择有机物蒸气冷凝器设计选用的总体传
22、热系数一般范围为5001500kcal/(.h.)本设计取k=600w/(.) 出料温度：64.6（饱和气）（饱和液）64.6冷却水温度：3040逆流操作：Dt1=34.6 Dt2=24.6Dtm=传热面积：A=在此温度下，查化工原理附录得g甲=1200KJ/Kg，g水=2378 KJ/KgQ=wg=1.0940.66570.99471220+（1-0.9947）2378=0.73031226=895.35KJ/sA=设备型号公称直径公称压力管程数管子根数中心排管数管程流通面积换热管长度计算换热面积f252.5600mm1.6MPa2232160.03643000mm52.82、再沸器的选择选
23、用120饱和水蒸气加热，传热系数取K=600w/(.)料液温度：99.6100 热流体温度：120120逆流操作：Dt1=20 Dt2=20.4 Dtm=同上w=rvVs=0.84270.6586=0.555Kg/sg=xwg甲+（1-xw）g水 查表知此温度下g甲=1100KJ/Kg g水=2400 KJ/Kgg=0.0028181100+（1-0.002818）2400=2396 KJ/Kgq=wg=23960.555=1329.8KJ/sA=设备型号公称直径公称压力管程数管子根数中心排管数管程流通面积换热管长度计算换热面积f252.5700mm4.00MPa4322210.0253450
24、0mm111.2（十）馏塔接管尺寸计算1、接管进料管的结构类型很多，本设计采用直管进料管，管径计算如下：D= 取=1.6m/s25进料，此温度下r甲=786.9Kg/m3 r水=996.95 Kg/m3 （查化工原理（上）附录）rLP=Vs=D=查标准系列 取f323回流管 采用直管回流管 取uR=1.6m/sDR=查表取f894塔釜出料管 取uw=1.6m/sDw=查表取f383塔顶蒸气出料筒 直管出气，取出口气速u=20m/sD=查表取f2738塔釜进气管 采用直管 取气速u=23m/sD=查表取f2738法兰本设计常压操作，采用进料管接管法兰2、筒体与封头筒体壁厚选6mm，所用材质为A3
25、 封头本设计采用椭圆形封头，由公称直径DN=800mm,曲面高度200mm，直边高度25mm，内表面积0.757，容积0.08m，选取风同样DN8006。（选自常用化工单元设备设计附表1（A）椭圆封头尺寸与质量（JB/T4729-94）除沫器当空塔气速较大带液现象严重，以及工艺过程中不许出塔气速夹带雾滴的情况下，设置除沫器，以减少液体夹带损失，确保气体纯度，保证后续设备的正常操作。常用除沫器有折流板式除沫器，丝网除沫器以及程流除沫器。本设计采用丝网除沫器，其具有比面积大、质量轻、空隙大及使用方便等优点。设计气速选取：，系数=0.107，除沫器直径：吊柱塔径D=800mm，可选用吊柱250Kg，
26、S=600mm，L=3150mm，H=900mm，材料用A3裙座塔底采用裙座支撑，裙座的结构性能好，连接处产生的局部阻力小，所用它是塔设备的主要支座形式，为了制作方便，一般采用圆筒形。由于裙座内径800mm，故裙座壁厚取16mm基础环内径：基础环外径：圆整：Dbi=1600mm，Db。=2200mm；基础环厚度，考虑到腐蚀余量取18mm；考虑到再沸器，裙座高度取3m（H2=3m），此角螺栓直径取M30人孔人孔是安装和检修人员进出塔的惟一通道，人孔的位置应便于进入任何一层塔板，由于设置人孔处塔间距离大且人孔设备过少会使制造时塔体的弯曲度难于达到要求 塔中共19块板，设置2个人孔，第6块和第7块板
27、之间设一块，第12块和第13块板之间设一块，每个孔直径为450mm，人孔处的板间距取700mm，塔顶和塔釜各设一人孔，裙座上再开2个人孔，直径为450mm，人孔伸入塔内部与塔内壁修平，其边缘倒棱和磨圆，人孔法兰的密封面及垫片用材与塔的接管法兰相同。进料段进料板设置在第5块板和第7块板之间，高度为700mm3、塔总体高度设计塔的顶部空间高度塔的顶部空间高度是指塔顶第一层塔盘到塔顶封头的直线距离，塔顶部空间高度设1200mm塔的底部空间高度塔的底部空间高度是指塔底最末一层塔盘到塔底下封头切线的距离，釜液停留时间取5minHb=塔体高度H塔高，m；没人孔处的板间距，m；n实际塔板数；板间距，m；裙座
28、高度，m；进料板处板间距，m；人孔数；塔底空间高度，m；塔顶空间高度。ag an employment tribunal clai Emloyment tribunals sort out disagreements between employers and employees. You may need to make a claim to an employment tribunal if: you dont agree with the disciplinary action your employer has taken against you your employer dismi
29、sses you and you think that you have been dismissed unfairly. For more informu, take advice from one of the organisations listed underFurther help. Employment tribunals are less formal than some other courts, but it is still a legal process and you will need to give evidence under an oath or affirma
30、tion. Most people find making a claim to an employment tribunal challenging. If you are thinking about making a claim to an employment tribunal, you should get help straight away from one of the organisations listed underFurther help. ation about dismissal and unfair dismissal, seeDismissal. You can
31、 make a claim to an employment tribunal, even if you haventappealedagainst the disciplinary action your employer has taken against you. However, if you win your case, the tribunal may reduce any compensation awarded to you as a result of your failure to appeal. Remember that in most cases you must m
32、ake an application to an employment tribunal within three months of the date when the event you are complaining about happened. If your application is received after this time limit, the tribunal will not usually accept i. If you are worried about how the time limits apply to you If you are being re
33、presented by a solicitor at the tribunal, they may ask you to sign an agreement where you pay their fee out of your compensation if you win the case. This is known as adamages-based agreement. In England and Wales, your solicitor cant charge you more than 35% of your compensation if you win the case
34、.youre clear about the terms of the agreement. It might be best to get advice from an experienced adviser, for example, at a Citizens Advice Bureau. To find your nearest CAB, including those that give advice by e-mail, click onnearest CAB.For more information about making a claim to an employment tr
35、ibunal, seeEmployment tribunals.The (lack of) air up there Watch m Cay man Islands-based Webb, the head of Fifas anti-racism taskforce, is in London for the Football Associations 150th anniversary celebrations and will attend Citys Premier League match at Chelsea on Sunday.I am going to be at the ma
36、tch tomorrow and I have asked to meet Ya ya Toure, he told BBC Sport.For me its about how he felt and I would like to speak to him first to find out what his experience was.Uefa hasopened disciplinary proceedings against CSKAfor the racist behaviour of their fans duringCitys 2-1 win.Michel Platini,
37、president of European footballs governing body, has also ordered an immediate investigation into the referees actions.CSKA said they were surprised and disappointed by Toures complaint. In a statement the Russian side added: We found no racist insults from fans of CSKA.Age has reached the end of the
38、 beginning of a word. May be guilty in his seems to passing a lot of different life became the appearance of the same day; May be back in the past, to oneself the paranoid weird belief disillusionment, these days, my mind has been very messy, in my mind constantly. Always feel oneself should go to d
39、o something, or write something. Twenty years of life trajectory deeply shallow, suddenly feel something, do it.一字开头的年龄已经到了尾声。或许是愧疚于自己似乎把转瞬即逝的很多个不同的日子过成了同一天的样子；或许是追溯过去，对自己那些近乎偏执的怪异信念的醒悟，这些天以来，思绪一直很凌乱，在脑海中不断纠缠。总觉得自己似乎应该去做点什么，或者写点什么。二十年的人生轨迹深深浅浅，突然就感觉到有些事情，非做不可了。The end of our life, and can meet many
40、things really do?而穷尽我们的一生，又能遇到多少事情是真正地非做不可？During my childhood, think lucky money and new clothes are necessary for New Year, but as the advance of the age, will be more and more found that those things are optional; Junior high school, thought to have a crush on just means that the real growth, but
41、 over the past three years later, his writing of alumni in peace, suddenly found that isnt really grow up, it seems is not so important; Then in high school, think dont want to give vent to out your inner voice can be in the high school children of the feelings in a period, but was eventually infarc
42、tion when graduation party in the throat, later again stood on the pitch he has sweat profusely, looked at his thrown a basketball hoops, suddenly found himself has already cant remember his appearance.童年时，觉得压岁钱和新衣服是过年必备，但是随着年龄的推进，会越来越发现，那些东西根本就可有可无；初中时，以为要有一场暗恋才意味着真正的成长，但三年过去后，自己心平气和的写同学录的时候，突然就发现是
43、不是真正的成长了，好像并没有那么重要了；然后到了高中，觉得非要吐露出自己的心声才能为高中生涯里的懵懂情愫划上一个句点，但毕业晚会的时候最终还是被梗塞在了咽喉，后来再次站在他曾经挥汗如雨的球场，看着他投过篮球的球框时，突然间发现自己已经想不起他的容颜。Originally, this world, can produce a chemical reaction to an event, in addition to resolutely, have to do, and time.原来，这个世界上，对某个事件能产生化学反应的，除了非做不可的坚决，还有，时间。A persons time, you
44、r ideas are always special to clear. Want, want, line is clear, as if nothing could shake his. Also once seemed to be determined to do something, but more often is he backed out at last. Dislike his cowardice, finally found that there are a lot of love, there are a lot of miss, like shadow really have b