Aspen Plus计算.docx

Aspen Plus多组分精馏简捷法计算-DSTWU计算主要步骤及参数设置在利用Aspen Plus计算前先做如下假设和说明：1.进料为饱和液体进料，因此进料中气相组分数为零。2.塔顶压力0.016MPa，假设进料为第30块理论板，采用CY型丝网填料，等板高度5块/m,填料压降5mmHg/m,则每块理论板压降为1mmHg/块，则进料板处的压力为：0.016+（30/760）0.1013=0.020MPa 。3.进料量3t/d= (3000kg)/(24h126.587kg/mol)=0.9875kmol/h4.回流比的初始值设定为25。5.塔顶产品中OCT回收率的计算进料中OCT：0.98750.4=0.3950 PCT=0.98750.6=0.5925所以塔顶产品中OCT的回收率=DXD/FZF=0.66667塔顶产品中PCT的回收率=D(1-XD)/F(1-ZF)=0.1111116.假设总板数为40，则塔底压力为： 0.016+（40/760）0.1013=0.02133MPa1Data，Setup1.1 specifications1.1.1 GlobalTitle: Separation of OVT and PCT-DSTWUInput data: MET1.1.2 Accounting: WXL1.2 Report Options, StreamFraction basis: MoleStream format: TFF: FULL2.Components 2.1 Specification2.1.1 Selection: Component ID type Component name Formula OCT Conventional o-chlorotoluene C7H7CL-D2PCT Conventional p-chlorotoluene C7H7CL-D33.Properties3.1Specifications3.1.1 Global: Base method: UNIFAc4.建立简捷计算法模拟流程图在主窗口下建立一精馏塔模型并连接物料流股线并重命名得下图所示流程图。简捷计算法模拟流程图5.Data,Setup,Streams5.1 FEED5.1.1SpecificationState variables:Vapor fraction= 0 Pressure： 0.020MPaTotal flow: 0.9875kmol/hComposition: Mole-Frac OCT=0.4 PCT=0.66.Blocks6.1 Input6.1.1SpecificationsReflux ratio: 25Light key: Comp-OCT Recov-0.666667Heavy key: Comp-PCT Recov-0.111111Pressure Condenser: 0.016MPa Reboiler: 0.021337进行计算，由Blocks，DSTWU，Results得到计算结果如下：RminRNminNFNT14参数修正进料板处压力修正为： 0.016+（23/760）0.1013=0.019066回流比修正为： R=14.151.3=18.395再沸器压力修正为：0.016+（35/760）0.1013=0.020665 MPa分别进入相应区域进行修正后计算得到结果如下：RminRNminNFNT14.106518.395264430Aspen Plus多组分精馏严格法计算-RADFRAC1Data，Setup1.1 specifications1.1.1 GlobalTitle: Separation of OVT and PCT-RADFRACInput data: MET1.1.2 Accounting: WXL1.2 Report Options, StreamFraction basis: MoleStream format: TFF: FULL2.Components 2.1 Specification2.1.1 Selection: Component ID type Component name Formula OCT Conventional o-chlorotoluene C7H7CL-D2PCT Conventional p-chlorotoluene C7H7CL-D33.Properties3.1Specifications3.1.1 Global: Base method: UNIFAC4.建立严格计算法模拟流程图在主窗口下建立一精馏塔模型并连接物料流股线并重命名得下图所示流程图。严格计算法模拟流程图5. Data,Setup,Streams5.1 FEED5.1.1Input, SpecificationState variable:Vapor fraction: 0 Pressure： 0.020MPa(NF=30)Total flow: 0.9875kmol/hComposition: Mole-Frac: OCT=0.4 PCT=0.66.Blocks,RADFRAC,Setup6.1ConfigurationNumber of stages: 44Condenser: TotalDistillate rate Mole 0.329167kmol/hReflux ratio Mole 18.3956.2 StreamsstageFeed 30Product streams: Top 1(stage) Liquid Botm 44(stage) Liquid6.3PressureStage1/Condenser pressure: 0.016MPaStage pressure drop: 1mmHg/块=0.0001333MPa or Column pressure drop:44mmHg=(44/760)0.1013=0.005865 MPa7.进行计算，由Data, Setup, Blocks, RADFRAC, Results Summary7.1 Summary View Condenser/Top stage Reboiler/Bottom stage7.2Stream ResultsTop: OCT=0.7772215 Botm: OCT=0.21138908.修改参数，重新计算在Blocks, RADFRAC, Setup中修改Configuration: Number of stage和 Stream: Feed的参数并进行重新计算，最终参数修改为：Configuration: Number of stage 51Stream: Feed 30计算得结果如下：Stream ResultsTop: OCT=0.80065320.8 Botm: OCT=0.1996731Feed/Product Streams Top 9.2 Vary, New, 1, OKType: Reflux ratioLower bound: 15U