HYSYS ® :An Introduction to Chemical Engineering Simulation B Presented by: Kazem Akbarzadeh Malihe mohamdi Abadan Institute of Technology 2

Process simulation Process simulation is used for the design, development, analysis, and optimization of technical processes such as: chemical plants, chemical processes, environmental systems,power stations, complex manufacturing operations, biological processes, and similar technical funcations. Process simulation is a model-based representation of chemical, physical, biological, and other technical processes and unit operations in software. Basic prerequisites are a thorough knowledge of chemical and physical properties of pure components and mixtures, of reactions, and of mathematical models which, in combination, allow the calculation of a process in computers. 3

Process simulation software describes processes in flow diagrams where unit operations are positioned and connected by product or educt streams. The software has to solve the mass and energy balance to find a stable operating point. The goal of a process simulation is to find optimal conditions for an examined process. This is essentially an optimization problem which has to be solved in an iterative process. Process simulation always use models which introduce approximations and assumptions but allow the description of a property over a wide range of temperatures and pressures which might not be covered by real data. Models also allow interpolation and extrapolation - within certain limits - and enable the search for conditions outside the range of known properties. 4

Hysys as the simulation tool Hysys is a Process modeling tool for steady-state simulation, design, performance monitoring, optimization and business planning for chemicals, specialty chemicals, petrochemicals and metallurgy industries. 5

Hysys Refinery Features Hysys Refinery solves the critical engineering and operating problems that arise throughout the lifecycle of a chemical process, such as: designing a new process troubleshooting a process unit optimizing operations of a full process With reliable thermodynamic data, realistic operating conditions and the rigorous Hysys Refinery equipment models, they can simulate actual plant behavior. 6

The process simulation capabilities of Hysys Refinery enables engineers to predict the behavior of a process using basic engineering relationships such as: mass and energy balances phase and chemical equilibrium reaction kinetics. 7

Contents Part 1. Starting with HYSYSStarting Part 2. Equations of StateEquations Part 3. PumpPump Part 4. CompressorCompressor Part 5. Conversion ReactionConversion Part 6. Equilibrium ReactionEquilibrium Part 7. Process Simulation Process Part 8. ReferencesReferences 8

Part 1 Starting with HYSYS 9

Starting HYSYS To start a new simulation case, do one of the following: From the File menu, select New and then Case. Click the New Case icon in the toolbar. The Simulation Basis Manager appears: 10

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Building the Simulation In building a simulation case HYSYS split the configuration options into two different environment: Basis environment enables you to specify the basic information like components, property package, reactions and so forth associated to the simulation. Case environment enables you to specify the streams and operation equipment associated to the simulation, and view the calculated results from the simulation. 12

Creating a New Simulation 13

Creating a Component List the next step is to select the components. You can create a list of components using the options on the Components tab of the Simulation Basis Manager property view or from the Set Up tab of the Fluid Package property view. The Component List property view appears. 14

Adding Component 15

There are a number of ways to select components for your simulation. One method is to use the matching feature. Each component is listed in three ways on the Selected tab: 16

Creating a Fluid Package The next step is to add a Fluid Package. As a minimum, a Fluid Package contains the components and property method (for example, an Equation of State) HYSYS will use in its calculations for a particular flowsheet. Depending on what is required in a specific flowsheet, a Fluid Package may also contain other information such as reactions and interaction parameters. 1. On the Simulation Basis Manager property view, click the Fluid Pkgs tab. 2. Click the Add button, and the property view for your new Fluid Package appears. 17

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Property Package Selection In the Property Package Selection group, you have access to the list of all the Property Methods available in HYSYS and to the Property Package Filter group. The Property Package Filter allows you to filter the list of available property methods, based on the following criteria: 19

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Note HYSYS has created a Fluid Package with the default name Basis-1. You can change the name of this fluid package by typing a new name in the Name field at the bottom of the property view. The property view is divided into a number of tabs. Each tab contains the options that enables you to completely define the Fluid Package. 21

Recommended Fluid Package 22

Enter Simulation Environment To leave the Basis environment and enter the Simulation environment, do one of the following: Click the Enter Simulation Environment button on the Simulation Basis Manager property view. Click the Enter Simulation Environment icon on the toolbar. 23

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When you enter the Simulation environment, the initial property view that appears depends on your current Session Preferences setting for the Initial Build Home property view. Three initial property views are available: PFD Workbook Summary Any or all of these can be displayed at any time; however, when you first enter the Simulation environment, only one appears. In this example, the initial home property view is the PFD (HYSYS default setting). 25

Object Palette 26

A number of new items are now available in the menu bar and toolbar, and the PFD and Object Palette are open on the Desktop. These latter two objects are described below. 27

Using the Workbook The Workbook displays information about streams and unit operations in a tabular format, while the PFD is a graphical representation of the flowsheet. Click the Workbook icon on the toolbar to access the Workbook property view. 28

Installing the Feed Streams In general, the first action you perform when you enter the Simulation environment is installing one or more feed streams. The following procedure explains how to create a new stream. On the Material Streams tab of the Workbook, type the stream name Feed 1 in the cell labelled **New**, and press ENTER. Your Workbook should appear as shown below. 29

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Specifying Material Streams In the previous section you specified the stream conditions in the Workbook property view. Next you will input the composition information in the Stream property view. The PFD becomes visible and displays a light blue arrow on it, labeled Feed 1. That arrow is the stream Feed 1 that you just created. 31

Alternative Methods for Defining Streams In addition to the method you just learned, there are several alternative ways to define streams. Access the Object Palette by pressing F4. Then Click the Material Stream icon on the Object Palette, then click on the Add Object icon. Press F11. From the Flowsheet menu, select Add Stream. Each of the above three methods creates a new stream and access the property view of the new stream. 32

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Double-click the blue arrow. The Feed 1 view appears. 34

Specifying The Compositions Click on the Composition page. By default, the components are listed by Mole Fractions. When you have entered the fraction of each component the total at the bottom of the property view will equal

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The compositions currently appear in Mass Fraction. To change this, click the Basis button, then select the appropriate radio button in the Composition Basis group of the property view that appears. 37

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The following table lists and describes the features available on the Input Composition for Stream property view: 39

Specifying The Temperature and Pressure 40

Specifying The Flow Rate 41

The properties of Feed 1 appear below. The values you specified are blue and the calculated values are black. 42

Part 2 Equations of State The ideal gas equation of state,which relates the pressure, temperature, and specific volume, is a familiar equation: The term p is the absolute pressure, V is the volume, n is the number of moles,R is the gas constant, and T is the absolute temperature. This equation is quite adequate when the pressure is low (such as one atmosphere).However, many chemical processes take place at very high pressure. Under these condition,the ideal gas equation of state may not be valid representation of reality. 43

Other equations of states have been developed to address chemical processes at high pressure. The first generalization of the ideal gas law was the van der Waals equation of state: This extension is just a first step, however, because it will not be a good approximation at extremely high pressure. The Redlich-Kwong equation of state is a modification of Vander Waal s equation of state, and then was modified further by Soave-Redlich-Kwong (SRK) equation of state. Which is a common one in process simulators. Another variation of Redlich- Kwong equation of state is Peng-Robinson (PR)equation of state. 44

For oil, gas and petrochemical applications, the Peng Robinson Equation of State is generally the recommended property package. Hyprotech’s enhancements to this equation of state enable it to be accurate for a variety of systems over a wide range of conditions. It rigorously solves most single phase, two phase and three-phase systems with a high degree of efficiency and reliability. All equation of state methods and their specific applications are described below: 45

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SRK & PR 47

Activity Models Although Equation of State models have proven to be very reliable in predicting the properties of most hydrocarbon based fluids over a wide range of operating conditions, their application has been limited to primarily non-polar or slightly polar components. Highly non-ideal systems are best modelled using Activity Models. The following Activity Model Property Packages are available: 48

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Chao Seader Models The Chao Seader and Grayson Streed methods are older, semi empirical methods. The Grayson Streed correlation is an extension of the Chao Seader method with special emphasis on hydrogen. Only the equilibrium data produced by these correlations is used by HYSYS. The Lee- Kesler method is used for liquid and vapour enthalpies and entropies. 50

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Vapour Pressure Models Vapour Pressure K-value models may be used for ideal mixtures at low pressures. Ideal mixtures include hydrocarbon systems and mixtures such as ketones and alcohols, where the liquid phase behaviour is approximately ideal. The models may also be used as first approximations for non- ideal systems: 52

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Miscellaneous The Miscellaneous group contains Property Packages that are unique and do not fit into the groups previously mentioned. 54

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Building the Simulation 57

Defining Necessary Stream 58

Preview the Results using Workbook To preview the result for the simulation: 1. go to tools menu and select Workbooks or click Ctrl+W as shown in below figure. 2. Next, click View and the Bookmark can be seen as shown in 59

Preview the Results using Workbook 60

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Workbook Configuration 62

Workbook Configuration 63

Analyze the property using case study In this section we will analyze the specific volume of n-butane when the temperature is changing. To do this analyze do the following: 64

Using Case Study 65

Variable Navigator 66

Data Book 67

Case Study Setup 68

Changing the Fluid Package 69

Part 3 Pump 70

Building the Simulation 71

Defining Necessary Stream 72

Adding New Operations 73

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Connecting Pump with Streams 75

Specifying the Pump Efficiency 76

Worksheet tab in Pump 77

Discussion 78

Part 4 Compressor 79

Building the Simulation 80

Hypothetical Component 81

Defining new Component 82

C7 + 83

Add Hypo 84

Adding a Feed Stream 85

Adding a Compressor 86

Compressor Efficiency 87

Outlet Temperature 88

Discussion 89

Part 5 Conversion Reaction 90

Problem Statement 91

Adding the Reactions 92

Adding stoichiometry 93

Adding Conversion 94

Adding the Reaction Sets 95

Making Sequential Reaction 96

Attaching Reaction Set to the Fluid Package 97

Adding the Feed Stream 98

Adding the Conversion Reactor 99

Data Entering 100

The Results 101

Review and Summery 102

Part 6 Equilibrium Reaction 103

Problem Statement 104

Defining the simulation Basis 105

Adding the Reactions 106

Adding stoichiometry 107

Adding the Reaction Sets 108

Attaching Reaction Set to the Fluid Package 109

Adding the Feed Stream 110

Adding the Equilibrium Reactor 111

Detail Page 112

The Results 113

Part 7 Process Simulation 114

Hints for Success in modeling 115

116 Steps in modeling of a Chemical Process

Self Study Aspen Hysys 2006 Guide\HYSYSTutorial.pdf 117

Aspen HYSYS Operations Guide, Aspen Technology, Inc., January Aspen HYSYS Tutorials & Applications, Aspen Technology, Inc., October Ikhyun Kim,HYSYS : Steady states and Dynamic Simulator Seoul National University,Fall Semester, HYSYS Design Tutorial for CHEE470, Queen’s University Department of Chemical Engineering,2009. Part 8 References 118