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1、AspenAspen高级班石油炼制过高级班石油炼制过程的模拟解读程的模拟解读高级精馏在化工领域的应用RADFRAC单元操作模型的应用、收敛方法和参数的单元操作模型的应用、收敛方法和参数的选取；选取；三相蒸馏、萃取蒸馏、共沸蒸馏和反应蒸馏等特殊蒸三相蒸馏、萃取蒸馏、共沸蒸馏和反应蒸馏等特殊蒸馏过程的模拟；馏过程的模拟；电解质过程的模拟等。电解质过程的模拟等。 2024/7/30石油炼制过程的模拟方法 以以一一套套典典型型的的常常减减压压装装置置为为主主线线，讲讲授授下下列列5部部分内容：分内容：1) 油品馏程分析数据的处理；油品馏程分析数据的处理；2) 初馏塔的模拟计算；初馏塔的模拟计算；3)
2、常压塔的模拟计算；常压塔的模拟计算；4) 减压塔的模拟计算；减压塔的模拟计算；5) 计算原油中所含杂质硫在各种产品中的分布。计算原油中所含杂质硫在各种产品中的分布。 2024/7/30掌握如下新的内容：1) 石油炼制过程蒸馏单元的模拟步骤；石油炼制过程蒸馏单元的模拟步骤；2) 流程模拟软件中石油馏份的特殊处理方法；流程模拟软件中石油馏份的特殊处理方法；3) 掌握掌握PETROFRAC单元操作模型的使用；单元操作模型的使用；4) 产品中杂质分布的计算。产品中杂质分布的计算。 2024/7/30复习：建立流程模拟模型的基本步骤确定模拟范围，绘制模拟流程图；确定模拟范围，绘制模拟流程图；将已知条件输
3、入相应表格：将已知条件输入相应表格：SETUPCOMPONENTSPROPERTIESSTREAMSBLOKS。运行模拟计算运行模拟计算检查结果检查结果2024/7/30油品分析和虚拟组分目标:学习输入石油分析数据学习输入石油分析数据, 创建调和组分创建调和组分(油品混合油品混合), 以及表征石油馏分以及表征石油馏分Aspen Plus 参考资料: User Guide, Chapter 6, Specifying Components User Guide, Chapter 32, Petroleum Assays and Pseudocomponents本章概况表征石油流体的挑战表征石油流
4、体的挑战油品馏程数据和性质数据的输入油品馏程数据和性质数据的输入蒸馏曲线的转换蒸馏曲线的转换生成虚拟组分生成虚拟组分油品调和油品调和用户自定义的虚拟组分用户自定义的虚拟组分2024/7/30石油的表征石油是烃类化合物和杂质组成的宽沸程的混合物石油是烃类化合物和杂质组成的宽沸程的混合物. 石油或石油馏分的性质取决于它们的组成，但是石油或石油馏分的性质取决于它们的组成，但是其组成难以定量分析其组成难以定量分析石油用虚拟组分石油用虚拟组分(pseudocomponents)来表征来表征, 虚虚拟组分是蒸馏曲线上较小的片断拟组分是蒸馏曲线上较小的片断. 每一个虚拟组分的基本性质由下列关联式来计算每一个
5、虚拟组分的基本性质由下列关联式来计算:分子量分子量(MW)正常沸点正常沸点(TBP)重度或者重度或者 Watson UOP K2024/7/30Assays 和 Blends 组分Assay Data(TBP, D86)PseudocomponentsAssay-1Assay-2BlendPseudocomponents输入输入输出输出2024/7/30输入油品馏程分析数据1.在在 Data Browser下面下面, 选择选择Components, 然然后选后选 Assay-Blend.2.在在 Assay-Blend 目标管理器下目标管理器下, 创建一个创建一个 assay 并且提供一个名称
6、并且提供一个名称(ID).3. 在在BasicDataDistCurve表中，输入蒸馏曲线表中，输入蒸馏曲线数据数据.4.在在BasicDataDistCurve表中，输入油品重度，表中，输入油品重度，或者在或者在BasicData Gravity/UOPK表中，输入表中，输入重度曲线或重度曲线或UOPK曲线数据曲线数据.虚拟组分将在模拟计算之初自动生成虚拟组分将在模拟计算之初自动生成.2024/7/30ASSAY组分的表征输入蒸馏曲线输入蒸馏曲线蒸馏曲线分割为很多个片段蒸馏曲线分割为很多个片段 (TBP Cut points)每一个片段生成一个虚拟组分每一个虚拟组分的性质每一个片段生成一个虚
7、拟组分每一个虚拟组分的性质以下列参数的平均值为基础进行估算：以下列参数的平均值为基础进行估算：分子量分子量 (MW)正常沸点正常沸点 (NBP)密度或比重密度或比重 (API or SG)虚拟组分的流率在流股结果表中报告虚拟组分的流率在流股结果表中报告.2024/7/30Assay组分BasicData DistCurve 表2024/7/30重度的规定油品整体重度油品整体重度 比重比重API 重度重度重度曲线重度曲线 比重比重API 重度重度 API=141.5/SG-131.5Watson UOPK 曲线曲线 NBP=(UOPK*SG)32024/7/30Assay组分BasicData
8、Gravity/UOPK 表2024/7/30蒸馏曲线蒸馏曲线类型蒸馏曲线类型:ASTM D86, D1160, D2887实沸点蒸馏曲线实沸点蒸馏曲线 (TBP) (重量或体积基准重量或体积基准)真空蒸馏曲线真空蒸馏曲线 (重量或体积基准重量或体积基准)每一个蒸馏曲线至少需要输入每一个蒸馏曲线至少需要输入4个点个点.报告中的蒸馏曲线为报告中的蒸馏曲线为:ASTM D86ASTM D1160Vacuum (liquid volume)2024/7/30油品分析数据计算程序油品分析数据计算程序Version 9 或更新的版本或更新的版本 Version 8 或更老的版本或更老的版本蒸馏曲线转换方
9、法蒸馏曲线转换方法ASTM D86 至实沸点至实沸点 (True boiling point)EdmisterEdmister-Okamota PMLD2887 至至 True boiling pointAPI87API94TBPWT蒸馏曲线计算方法2024/7/30曲线处理选项曲线处理选项初馏点初馏点 (Initial boiling point)0.5% (缺省缺省)终馏点终馏点 (Final boiling point)99% (default)外延方法外延方法Probability (缺省缺省)Quadratic锯齿段拟合方法锯齿段拟合方法Harwell (缺省缺省)Hermite曲线
10、处理选项在曲线处理选项在 ComponentsPetroCharacterization AnalysisOptions AssayProcedure表上表上.蒸馏曲线计算方法 (续)2024/7/30虚拟组分从油品分析数据生成虚拟组分从油品分析数据生成. 你可以规定切割温度或切你可以规定切割温度或切割片段割片段(窄馏份窄馏份)的宽度的宽度.ComponentsPetroCharacterizationGenerationCuts表上，规定切割温度等表上，规定切割温度等.缺省值是缺省值是40个切割点个切割点:TBP Range(F)100 - 800No. of CutsIncrements(
11、F)800 - 1200 1200 - 160028842550100切割温度2024/7/30蒸馏曲线的切割2024/7/30虚拟组分性质用用Watson/UOP “K”和和API关联式估算：关联式估算：典型地典型地10 UOPK 13此处此处 10.0 表示芳烃含量很高表示芳烃含量很高13.0 表示烷烃含量很高表示烷烃含量很高2024/7/30所生成虚拟组分的命名ComponentsPetro CharacterizationGeneration 规定命名选项规定命名选项自动生成的名称可以是自动生成的名称可以是:实际计算出来的实际计算出来的 NBP (如如: PC864F)沸程下限温度沸程
12、下限温度 (如如: PC800F)沸程上限温度沸程上限温度 (如如: PC900F)用户选择的顺序号用户选择的顺序号 (如如: PC1, PC2 )用户定义的名称用户定义的名称2024/7/30附加的ASSAY组分数据可选的性质曲线可选的性质曲线:轻端组分分析轻端组分分析 (light-ends matching)比重或者比重或者API重度曲线重度曲线Watson UOPK 曲线曲线分子量曲线分子量曲线性质曲线性质曲线 (多于多于30种性质种性质)绝对绝对 & 动力粘度曲线动力粘度曲线如果输入油品整体性质，单独的曲线数值被归如果输入油品整体性质，单独的曲线数值被归一到整体性质一到整体性质.可以
13、应用用户性质曲线可以应用用户性质曲线2024/7/30Assays组分的用户性质曲线在表格在表格PropertiesAdvancedUser Properties 上，建立用户性质曲线上，建立用户性质曲线. 在表格中激活在表格中激活 Assay Curve properties 选项选项在在 表格表格ComponentAssay/BlendProperty Curve上，输入用户性质曲线的数据。上，输入用户性质曲线的数据。对于高度非线性调和现象，如马达法辛烷值，对于高度非线性调和现象，如马达法辛烷值，建议使用用户调和子程序。建议使用用户调和子程序。2024/7/30性质曲线的流股计算性质曲线被
14、切割为与虚拟组分同样多的片段。性质曲线被切割为与虚拟组分同样多的片段。为每一个片段计算出平均的性质数值为每一个片段计算出平均的性质数值流股的性质数值由虚拟组分以及它们在流股中流股的性质数值由虚拟组分以及它们在流股中的浓度做调和计算得出的浓度做调和计算得出计算虚拟组分混合物的性质，有各种调和计算计算虚拟组分混合物的性质，有各种调和计算选项。选项。2024/7/30石油性质的调和石油性质调和方法石油性质调和方法:标准体积标准体积 (StdVol)摩尔摩尔 (Mole)质量质量 (Mass)用户用户 (User)用于性质计算的用户调和子程序：用于性质计算的用户调和子程序：用户子程序名称为用户子程序名
15、称为 BLDPPU.“调和选项调和选项”可以规定可以规定.性质可以外延与否性质可以外延与否.在在 Components Petro CharacterizationAnalysis OptionsBlend Options 上，调和规则可以修改。上，调和规则可以修改。2024/7/30Assay(石油)数据库 软件内置的软件内置的Assay 数据库，包含数据库，包含 194 种石油种石油的分析数据的分析数据, 其中有其中有:- 来自来自Phillips 石油数据库的石油数据库的10 种石油种石油 -来自文献的来自文献的184种石油种石油 在在 Component SpecificationsP
16、etroleum表，表，查找查找Assay 库文件。库文件。和和Phillips Petroleum 石油分析数据库的接口，石油分析数据库的接口，其中收集了超过其中收集了超过250种石油的数据种石油的数据 *需要与需要与Phillips Petroleum签订签订License协议。协议。2024/7/30Assay(石油)数据库每一种石油至少提供如下信息每一种石油至少提供如下信息:馏程分析馏程分析重度重度 和和/或或 重度曲线重度曲线某些石油有附加的性质曲线某些石油有附加的性质曲线:苯胺点苯胺点闪点闪点凝固点凝固点硫含量硫含量金属含量金属含量硫醇硫醇研究法研究法/马达法马达法 辛烷值辛烷值烷
17、烃烷烃环烷烃环烷烃芳烃芳烃雷诺蒸汽压雷诺蒸汽压2024/7/30访问Assay数据库2024/7/30创建Blends组分通过规定通过规定blend 中每个中每个assay 的百分数，由的百分数，由assay创建创建blend.调和可以是调和可以是 Mole, Mass, 或或 StdVol基准基准.要创建一个要创建一个blend，至少规定，至少规定2个个assay组分组分.一个一个blend中的中的 assay的数量没有上限的数量没有上限.报告中的蒸馏曲线为报告中的蒸馏曲线为:ASTM D86ASTM D1160Vacuum (liquid volume)2024/7/30输入 Blend组
18、分1.在数据浏览器在数据浏览器 Data Browser, 选择组分选择组分 Components, 然后选择然后选择 Assay-Blend.2.In the Assay-Blend 目标管理器目标管理器, 创建一个创建一个 blend 并且提供名称并且提供名称(ID ).3.在在Mixture Specifications表上，输入各表上，输入各 assay 组分的调和分数组分的调和分数.虚拟组分将在模拟计算之初自动生成虚拟组分将在模拟计算之初自动生成.2024/7/30Blend组分之 MixtureSpecifications表2024/7/30Assay/Blend 结果Assay/
19、blend 的计算结果的计算结果 可以在表格可以在表格 ComponentsAssay-Blend Results查看查看. 每一个每一个assay 或或 blend 组分有自己单独的结组分有自己单独的结果表格果表格(results form).2024/7/30GenerationCuts 表格2024/7/30虚拟组分的生成缺省情况缺省情况, 一套完整的虚拟组分由输入的所有一套完整的虚拟组分由输入的所有 assay组组分生成分生成.在表格在表格ComponentsPetro Characterization Generation Specifications上，用户可以规定生成上，用户可以
20、规定生成虚拟组分时，包括虚拟组分时，包括/不包括特别的不包括特别的assay.只有在表格只有在表格 GenerationSpecifications上选出的上选出的assays和和 blends ，才用于生成虚拟组分。，才用于生成虚拟组分。在表格在表格 GenerationSpecifications上未选用的上未选用的Assays or blends，将不被使用，将不被使用， 它们的它们的IDs 不在不在 流股输入表格上显示流股输入表格上显示. 2024/7/30虚拟组分命名虚拟组分的命名约定虚拟组分的命名约定计算出的沸点计算出的沸点 (例如：例如： PC125, PC136, )规定起始编
21、号规定起始编号切割温度上限切割温度上限 (例如：将例如：将225-250F 窄馏份命名为窄馏份命名为PC250)切割温度下限切割温度下限 (例如：将例如：将225-250F 窄馏份命名为窄馏份命名为PC225)用户定义的名称列表用户定义的名称列表 在表格在表格 Components Petro CharacterizationGenerationNaming Options 上，规定命名约定上，规定命名约定.如果你要将如果你要将Aspen Plus 生成的虚拟组分与反应器生成的虚拟组分与反应器或者分离模块关联，应使用用户定义的名称列表。或者分离模块关联，应使用用户定义的名称列表。2024/7/
22、30GenerationNamingOptions表格2024/7/301. 在表格在表格 ComponentsSpecificationsSelection上，上， 输入组分输入组分 IDs 并且选择并且选择 Pseudocomponent类型。类型。2.在表格在表格 ComponentsPseudocomponentsSpecifications 上上, 至至少提供下列参数中的两个：少提供下列参数中的两个： 正常沸点正常沸点 NBP, 重度重度 Gravity (Specific gravity, API gravity, or Liquid density), 分子量分子量 Molecu
23、lar weightAspen Plus 可以估算第可以估算第3性质性质.3.可选地可选地, 输入与温度相关的性质数据输入与温度相关的性质数据:液相粘度液相粘度 Liquid viscosity水溶解度水溶解度 Water solubility饱和蒸汽压饱和蒸汽压 Vapor pressure定义用户虚拟组分2024/7/30虚拟组分规定表格2024/7/30虚拟组分物性方法方法名称描述API-METHCOAL-LIQLKAPI-TWUAPI procedureCorrelations for coal-liquid fractionsLee Kesler correlationsAPI pr
24、ocedure with Twu correlationsfor critical propertiesASPEN (default)API procedure with Aspen modifications注意: 不要将虚拟组分物性方法与流程模拟物性方法混淆， 前者只是用于虚拟组分石油性质参数的计算。2024/7/30虚拟组分计算结果生成的虚拟组分在表格生成的虚拟组分在表格 Components Petro CharacterizationResults上浏览检查。上浏览检查。2024/7/30表格Analysis OptionsAssay Procedure2024/7/30石油性质模型
25、基本的虚拟组分性质模型基本的虚拟组分性质模型分子量分子量 Molecular Weight临界温度临界温度 Critical Temperature临界压力临界压力 Critical Pressure临界体积临界体积 Critical Volume偏心因子偏心因子 Accentric Factor饱和蒸汽压饱和蒸汽压 Vapor Pressure液相摩尔体积液相摩尔体积 Liquid Molar Volume水溶解度水溶解度 Water Solubility粘度粘度 Viscosity基本的虚拟组分性质模型可以在表格基本的虚拟组分性质模型可以在表格ComponentsPetro Charact
26、erizationProperties MethodsBasic 上修改。上修改。2024/7/30石油性质模型 (续)虚拟组分热力学性质模型虚拟组分热力学性质模型理想气体热容理想气体热容 Ideal Gas Heat Capacity汽化焓汽化焓 Enthalpy of Vaporization标准生成焓标准生成焓 Standard Enthalpy of Formation标准生成自由能标准生成自由能 Standard Free Energy of Formation基本的虚拟组分性质模型可以在表格基本的虚拟组分性质模型可以在表格ComponentsPetro Characterizati
27、on Properties MethodsThermodynamic上修上修改改.2024/7/30石油性质模型 (续)虚拟组分状态方程虚拟组分状态方程(EOS)性质模型性质模型RKS Interaction ParametersBWR Orientation ParameterBWR Critical TemperatureBWR Critical Volume基本的虚拟组分性质模型可以在表格基本的虚拟组分性质模型可以在表格ComponentsPetro Characterization Properties MethodsEOS上修改上修改.2024/7/30石油交互作用参数虚拟组分与下列
28、常规组分的交互作用参数虚拟组分与下列常规组分的交互作用参数Kijs :H2SN2CO2COH2CH42024/7/30物性方法的修改用户可以建立自己的虚拟组分石油性质方法用户可以建立自己的虚拟组分石油性质方法.各种性质的计算模型可以改变各种性质的计算模型可以改变.大多数虚拟组分性质可以应用子程序大多数虚拟组分性质可以应用子程序.在线帮助中有每一种性质方法的简要说明在线帮助中有每一种性质方法的简要说明2024/7/30流程模拟计算在流程模拟计算期间在流程模拟计算期间, 不区分虚拟组分和真实不区分虚拟组分和真实组分组分.产品流股中的虚拟组分调和在一起，并且生成产品流股中的虚拟组分调和在一起，并且生
29、成蒸馏曲线蒸馏曲线产品终馏点产品终馏点 (即即 D86 95% point) 或者初馏点或者初馏点 (D86 5% point) 可以规定为单元操作的性能可以规定为单元操作的性能指标：指标：塔内部的设计规定塔内部的设计规定用于其它单元操作的外部设计规定用于其它单元操作的外部设计规定2024/7/30检查蒸馏塔各产品之间的分离效果(重叠度)2024/7/30Petroleum Properties and Property SetsObjective:Become familiar with petroleum properties and learn the use of stream ana
30、lysisAspen Plus References: User Guide, Chapter 32, Petroleum Assays and PseudocomponentsPetroleum PropertiesReid vapor pressureAPI and specific gravityWatson UOP K factorAniline pointPour pointFlash pointCetane numberCarbon to hydrogen ratioGross heating value2024/7/30Petroleum Properties (Continue
31、d)Mean and volume average boiling pointHydrate formation pressure and temperatureRefractive indexLiquid viscosity indexD86 temperatures at (0, 5, 10, 95%)D1160 temperatures at (0, 5, 10, 95%)D2887 temperatures at (0, 5, 10, 95%)TBP temperaturesVacuum temperatures2024/7/30Petroleum Properties (Contin
32、ued)Properties (curves) from Assay AnalysisPointsAniline, cloud, flash, freeze, smokeContentsAromatic, olefin, paraffin, naphthalene, mercaptanC, H, O, NImpurities: S, V, Fe, NiIndices:Antiknock, vapor knock, refractive, warm-upNumbers:Motor and research octaneLuminometerViscosityGenerally input cur
33、ves for assays to generate these curves for product streams is needed.2024/7/30Distillation CurvesVolume and weight basisASTM D86ASTM D1160ASTM D2887 (weight percent only)VacuumTBPAPI GravityGravity MW2024/7/30Property SetsA property set (Prop-Set) is a way of accessing a collection, or set, of prop
34、erties as an object with a user-given name. Only the name of the property set is referenced when using the properties in an application.Use property sets to report thermodynamic, transport, and other property values.Current property set applications include:Design specifications, Fortran blocks, sen
35、sitivityStream reportsPhysical property tables (Property Analysis)Tray properties (RadFrac, PetroFrac, etc.)Heating/cooling curves (Flash2, MHeatX, etc.)2024/7/30Properties included in Prop-SetsProperties commonly included in property sets include:API- API gravitySGSTD - Standard specific gravity (6
36、0 F, 1 atm)REIDVP- Reid vapor pressureD86T - D86 temperatureMUMX - ViscosityAvailable properties include:Thermodynamic properties of components in a mixturePure component thermodynamic propertiesTransport propertiesElectrolyte propertiesPetroleum-related propertiesReference: Aspen Plus Physical Prop
37、erty Data Reference Manual, Chapter 4, Property Sets has a complete list of properties that can be included in a property set.2024/7/30Defining Property SetsSpecifications for a property set include:Property name and unitsTemperature and pressure at which to calculateInclude or exclude waterphase qu
38、alifier (V, L, L1, L2, T, S) 2024/7/30Specifying Property SetsUse the Properties Prop-Sets form to specify properties in a property set.The Search button can be used to search for a property.All specified qualifiers apply to each property specified, where applicable.Users can define new properties o
39、n the Properties Advanced User-Properties form by providing a Fortran subroutine.2024/7/30Predefined Property SetsSome simulation Templates contain predefined property sets. The following table lists predefined property sets and the types of properties they contain for the General Template:2024/7/30
40、Predefined Petroleum Prop-Sets (Continued) Predefined Prop-Sets with the Petroleum Application template:PREDEFINEDPROPERTY SETTYPES OF PROPERTIESCUTS - E Volumetric flow rate of petroleum cuts at 100F intervals D86 - 5 ASTM D86 temperature at 5% liquid volume distilled D86 - 95 ASTM D86 temperature
41、at 95% liquid volume distilledGAS - PROPS Compressibility, volumetric flow rate, heat capacity ratio KINVISC Liquid kinematic viscosity at 100F and 212F LIGHT Petroleum characteristics for light distillates MIDDLE Petroleum characteristics for middle distillates PETRO Volumetric flowrate, gravity, W
42、atson K, distillation curves TBP-5 True boiling point temp. at 5% liquid volume distilled TBP-95 True boiling point temp. at 95% liquid volume distilled2024/7/30Petroleum Prop-SetsMost petroleum properties are calculated from input property curves.Some petroleum properties are calculated from correl
43、ations (FLSH-API, POUR-API)Properties are accessed and used in exactly the same way as other prop-set properties2024/7/30Stream Results OptionsOn the Setup Report Options Stream sheet, use: Flow Basis and Fraction Basis check-boxes to specify how stream composition is reportedProperty Sets button to
44、 specify names of property sets containing additional properties to be reported for each stream2024/7/30Prop-sets Discussion1. Give two reasons that a property set is needed.2. How do you define a property set?3. A user defined a prop-set for viscosity and then ran the simulation. After the simulati
45、on was complete, he opened the stream results. To his surprise, he did not see viscosity. What happened?2024/7/30PetroFracObjective:Introduce the features of the PetroFrac model and its use in simulating a crude towerAspen Plus References: Unit Operation Models Reference Manual, Chapter 4, ColumnsCh
46、aracteristics of Refining ProcessWide boiling range fluidsLarge temperature gradients along columnMost fluid compositions are unknown but their distillation analysis is knownThree phase with free waterSide strippers and pumparoundsPetroleum specific physical propertiesHigh degree of heat integration
47、Metal and sulfur contents2024/7/30Petroleum Refining ApplicationsPetroFrac is a distillation model specifically designed for petroleum refining applications:preflash towercrude unitvacuum unitvacuum lube fractionatorFCC main fractionatordelayed coker main fractionatorquench tower/primary fractionato
48、r 2024/7/30PetroFrac FeaturesIntegration of furnace, column, side stripper and pumparoundADA/PCS for assay input, crude blend and breakdownConversion between different ASTM curvesUser specification of cutsPetroleum oriented specificationsTray and packing sizing and ratingOther featuresInitialization
49、 and convergence2024/7/30Example Crude TowerGASDECANT WATERNAPHTHAJET FUELKEROSENEDIESEL GAS OILRESIDCRUDE FEEDSTEAM2024/7/30PetroFrac - ConnectivityVapor DistillateBottomsFeedsFeedsOverflashPumparoundPumparoundStripper BottomsLiq ReturnSide ProductsOverheadLiquid DistillateWater DistillateFeedHeatB
50、ottom Stage orReboiler Heat DutyTop Stage or Cond. Heat DutyHeat or Reboiler Heat DutySteam Feed2024/7/30PetroFrac - Flowsheet ConnectivityAny number of pumparounds and side strippersSteam or reboiler strippersStripper hot liquid returnMultiple feeds to strippersTotal pumparound and product drawoffs
51、Interstage water decantersHeat streams for pumparound coolersPseudostreams2024/7/30PetroFrac - Model SpecificationsSetup form (required)Number of stagesCondenser and ReboilerDistillate rate, Bottoms rate, Condenser duty, Reboiler duty, or Reflux RatioFeed/Product (required)Feed convention: furnace,
52、on-stage, above-stagePres-Profile (required)PumparoundsStrippers2024/7/30PetroFrac - Pumparound SpecificationsDraw and return stage locations (required)For total drawoffs, specify one of the following:return temperaturetemperature change (negative if cooled)duty (negative if cooled)For partial drawo
53、ffs, specify liquid flow rate and one of the above.2024/7/30PetroFrac - Side Stripper SpecificationsStage NumberFor each stripper, the trays are numbered from top to bottom starting with stage 1.Steam StripperSpecifying a steam-to-product ratio will override the steam flow rate.Reboiler StripperSpec
54、ify a reboiler duty.2024/7/30PetroFrac - Side StripperConventionsLiquid draw always goes to the stripper top stage.Vapor always returns to the main columnOther SpecificationsA fraction of the stripper bottoms can be returned to the main columnMultiple drawoffs from different stages as feeds to the s
55、ame stripper are allowed 2024/7/30PetroFrac - Other SpecificationsSteam to product flow ratio (mass)Feed overflashFurnace outlet temperatureLiquid runback from a stageASTM temps and gapsPetroleum properties (RVP, flash point, pour point, etc)Murphree efficiencyMultiple property option specifications
56、Free water calcs in the condenser or on all traysBlocks PetroFrac Properties form to specify internal stages checked for free water - condenser is checked automaticallyTray/packing2024/7/30PetroFrac - Design SpecificationsMeet product property by varying:stripping steam flow rate/reboiler dutyproduc
57、t flow ratepumparound flow rate or return temperaturefurnace temperatureMeet a particular stage temperature by varying:furnace outlet temperaturepumparound flow rate or return temperatureMeet product flow rate by varying:furnace outlet temperature2024/7/30PetroFrac - DefinitionsRunbackLiquid flow ra
58、te from a stage to a lower stage, equivalent to stage liquid flow rate less side drawsThe Runback form is used to specify the runback from a stage. The manipulated variable is the pumparound duty or flow rateLiquid FlowIn PetroFrac, stage liquid flow reported in the tray profile is the sum of runbac
59、k, side draw, and pumparound.In RadFrac, stage liquid flow excludes any side product draw and pumparound. 2024/7/30Outside LoopPhysical Properties (ai, KB, HV, HL)Inside Loopcmi = cmi outyi = Ki xiS xi = 1.0, S yi = 1.0S Hi in = S Hi outl, v, x, y,L = S li, V = S vi TInside loop solved byNewton meth
60、od withor without log-legPetroFrac - ConvergenceSum-Rates variant of the inside-out algorithm2024/7/30PetroFrac - ConvergenceAlgorithm: sum-rates variant of the inside-outInitialization: designed for refining applicationTo enhance convergence:provide column/stripper temperature estimatesvary converg
61、ence damping factors to enhance stabilitychange design specifications2024/7/30PetroFrac - Summary1.PetroFrac combines Furnace, Column, Pumparound, and Sidestripper into one model which makes the simulation easy to setup and converge.2.Feed characteristics can be user input or from the assay library.
62、3.Multiple feeds can be blended to create a feed mixture.4.Additional properties of a particular product can be reported by adding property sets.5.Runback from a stage is the liquid flow rate leaving the stage and entering the stage below. Runback and liquid flow can be different.6.Most crude towers
63、 do not have a reboiler at the bottom. Either the bottom steam rate or the furnace duty is varied to meet the energy requirement (energy balance). 2024/7/30PetroFrac - Discussion1.RadFrac and MultiFrac can also be used to simulate the crude tower. Why choose PetroFrac?2. If you have the characterist
64、ics of all the products, but not the crude, how do you run the simulation?3. Can you change the number of cuts for pseudocomponents? Under what conditions should you increase or decrease the number of pseudo components?4. How do you control the property of a side draw?5. Are you confident that you c
65、an build your own model from this workshop?6. Is there any function that you dont know or see in Aspen Plus?2024/7/30Pseudo streams in PetroFracWhat is a pseudo stream?Why are pseudo streams useful?How are they created?2024/7/30Pseudo StreamAn imaginary stream that references a column internal fluid
66、The pseudo stream includes:TemperaturePressureCompositionFlowratePseudo stream values do not affect the calculations or mass balance inside the source columnPseudo streams may be fed to another unit operation, or become a terminating product stream2024/7/30Uses for Pseudo StreamsAccess quality and c
67、ondition of any column internal fluid (these normally dont show up in any other report)Tray fluidsStripper fluidsPumparound fluidsModel column internal equipment by connecting pseudo streams to:Pumparound heat exchangersOverhead condensers2024/7/30Locating the Pseudo Stream Port2024/7/30Creating a P
68、seudo Stream1. Connect a material stream to the columns pseudo stream connection port.2. Optional: Connect the material stream to another unit operation.Drag the pseudo stream connection port to another side or part of the column icon.3. Hit the next button. 4. Define the pseudo stream source on the
69、 Column Report Pseudo Streams sheet.2024/7/30Column Report Pseudo Streams Sheet2024/7/30Pseudo Stream ResultsLocated in the stream summaryNOT Part of the overall mass balanceNot part of the source unit balanceNot part of the overall flowsheet balance (Sum of Feeds = Sum of Products)Attached or destination unit results do not differentiate between a real or pseudo stream2024/7/30结束结束
