DWSIM/C2/Rigorous-Distillation/English-timed

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Time Narration
00:01 Welcome to this tutorial on Simulating a Rigorous Distillation column in DWSIM.
00:07 In this tutorial, we will learn to:
00:10 Simulate a Rigorous Distillation column
00:13 Specify column Pressure Profile
00:16 Specify Tray Efficiencies
00:19 Check desired product compositions and
00:22 View the Column profiles
00:25 This tutorial is recorded using

DWSIM 5. 8 (Classic UI) Update 3 and Windows 10 OS.

00:36 But, this process is identical in Linux, Mac OS X or FOSSEE OS on ARM.
00:44 To practise this tutorial, you should know to-

Add components to a flowsheet

00:50 Select thermodynamic packages
00:53 Add material and energy streams and specify their properties.
00:58 The prerequisite tutorials are available on this website.
01:03 You can access these tutorials and all the associated files from this site.
01:09 shortcut-end file used in the tutorial is provided as a Code file on this tutorial page.
01:17 Download the files from Code Files link.
01:21 I have already opened DWSIM on my machine.
01:26 I have opened the file shortcut-end.dwxmz.
01:32 Let me save this as rigorous.
01:37 We can see that the file name has changed now to rigorous.
01:42 Click on the Settings button on the toolbar.
01:46 Click on Systems of Units tab.
01:49 Locate Pressure menu on the right hand column.
01:53 Click and choose atm for atmosphere.

Press Enter.

01:59 Similarly, change the units of Delta_P to atm.

Press Enter.

02:06 Close the Settings window.
02:09 Let me switch to the slides.
02:12 This problem was solved in the spoken tutorial on Shortcut Distillation.
02:18 These values form the basis for the rigorous distillation column problem.
02:24 This represents the solution of the given problem using Shortcut Distillation.
02:30 We will be using these values shortly.
02:33 Let us begin by replacing the Shortcut column with a Rigorous column.
02:38 Let me go back to the simulation.
02:41 Right-click on the Shortcut column, and select delete.

Click Yes in the prompt box.

02:49 At the bottom of the main simulation window, go to Columns tab.
02:54 From the displayed list, drag and drop a Distillation Column to the Flowsheet.
02:59 Let’s us now arrange it as required.
03:02 Click on the Distillation Column.
03:05 On the left, go to the Property Editor Window of the Distillation Column.
03:10 Now under Column Specs, click on the General tab.
03:15 Locate the Number of Stages option.
03:18 We have to enter the total number of trays here.
03:22 We got the equilibrium stages to be 20 from the shortcut method.
03:27 We can see it in the slide.

Let us go back to DWSIM.

03:33 This number should be one more than the equilibrium stages given by shortcut method.
03:39 So, change the Number of Stages to 21 and press Enter.
03:46 This number includes the condenser also in DWSIM.
03:51 So here we will use a total condenser.
03:56 Now we will select the solution method.
03:59 Click on the drop-down against Solver.
04:03 Choose the Solver as Wang-Henke (Bubble Point), if not already selected.
04:09 By default, Wang-Henke (Bubble Point) is already selected as Solver.
04:15 Now we will connect the streams to the Distillation column.
04:20 Go to Column Configuration section.
04:23 Navigate to Connections >> Streams Connections >> Feeds
04:29 Here we have to specify the stream which is entered as a feed to the column.
04:35 Here, we can see the list of Feed Ports.
04:39 Select any port where we want the feed to enter the Distillation column.
04:44 For a better look, we select Column Feed Port 5.
04:48 Click on the down-down against Column Feed Port 5.
04:53 Select Feed and press Enter.
04:56 In a similar way, we will connect the product streams.
05:00 Now, click on the Products tab.
05:03 Select Distillate as Distillate and press Enter.
05:08 Select Bottoms as Bottoms and press Enter.
05:13 Now we will connect heat duties to reboiler and condenser.
05:18 Click on the Duties tab.
05:20 Select Reboiler Duty as R-Duty and press Enter.
05:25 Select Condenser Duty as C-Duty and press Enter.
05:31 Now under Connections, click on Stream-Stage Associations tab.
05:37 For Feed Port type, select Stage location as Stage9.

Press Enter.

05:44 This is as per the solution we got in the Shortcut Distillation column.
05:49 We got the Optimal Feed Location to be 9 from the Shortcut method.
05:54 We can see it in the slide.

Let us go back to DWSIM.

06:00 This completes the connections.
06:03 Now we have to provide the top and bottom specifications.
06:08 Under Properties tab, locate the section Column Specs.
06:13 Click on the Condenser tab.
06:16 Select Condenser Type as Total, if not already selected.
06:21 By default, it is total condenser.

We will leave it as it is.

06:25 Change Condenser Pressure to 1 atmosphere and press Enter.
06:32 Select Condenser Pressure drop as 0.

By default, it is 0. We will leave it as it is.

06:40 Next select the Specification as Reflux Ratio, if not already selected.
06:47 By default, Reflux Ratio is already selected as Specification.
06:53 Under Compound, we can see a field.
06:56 Here we can enter the value of reflux ratio.
07:00 We will enter the Reflux Ratio as 2.317.

Press Enter.

07:06 Now click on Reboiler tab.
07:10 Change Reboiler Pressure to 1.1 atmosphere and press Enter.
07:16 Select Specification as Product Molar Flow, if not already selected.
07:22 Under Compound, change the units to kilomol per hour and press Enter.
07:29 Now enter the Molar flow rate as 60.204.

Press Enter.

07:36 This is suggested by the shortcut solution.

We can see it in the slide.

07:43 Let us go back to DWSIM.
07:46 Now we will also see how to specify the pressure for the intermediate stages.
07:53 Now go to Column Configuration section.
07:56 Click on Stages tab.
07:59 It shows the condenser and reboiler pressures as 1 and 1.1 atmosphere.
08:06 New stages that have been added, are assigned zero pressure, which is incorrect.
08:12 We would like the intermediate stage pressures to take the interpolated values.
08:18 Under Column Configuration section, go to the extreme left.
08:23 Here we can see 5 different icons.

Hover the mouse to the last icon.

08:30 A popup is displayed as Estimate Stage Pressures by Interpolation.

Click on the icon.

08:38 Immediately, linearly interpolated values are assigned to every stage.
08:44 We can also edit the pressure of the individual stages, if they are known.
08:50 We may also change the efficiency in one or more stages.
08:55 Now we will run the simulation.
08:58 Click on Solve Flowsheet button on the toolbar.
09:02 When the calculations are completed, click on the Distillation column.
09:07 Go to the Property Editor Window of the Distillation Column.
09:12 Locate the Results section.
09:15 This shows all the required results like
Condenser Duty ,  Reboiler Duty and  Column Profiles 
09:23 Now let us look at the Column profiles.
09:27 Click on View Temperature, Pressure and Composition Profiles button.
09:33 Now we can see a pop-up window.
09:37 Here, we can see the- Temperature profiles, Flows profiles, Component flows and Component fractions
09:50 For the exact numbers, click on the Table tab to the right of the Graph tab.
09:56 Now save this file.
09:59 Let us summarize
10:03 In this tutorial, we have learnt to:

Simulate a Rigorous Distillation column, Specify column Pressure Profile

10:11 Specify Tray Efficiencies, Check desired product compositions and View the Column profiles
10:20 Take the Assignment from the Shortcut Distillation column.
10:24 Perform the simulation using Rigorous Distillation.
10:28 Here is the assignment problem statement of the Shortcut Column.
10:33 With this, we have come to the end of this tutorial.
10:37 Watch the video available at the following link.

It summarizes the Spoken Tutorial project.

10:45 The Spoken Tutorial Project Team, Conducts workshops and Gives certificates.
10:51 For more details, please write to us.
10:54 Please post your time queries in this forum.
10:58 The FOSSEE team coordinates conversion of existing flowsheets into DWSIM.
11:04 We give honorarium and certificates for those who do this.

For more details, please visit this site.

11:13 The FOSSEE team helps migrate commercial simulator labs to DWSIM.
11:19 We give honorarium and certificates for those who do this.

For more details, please visit this site

11:28 Spoken Tutorial and FOSSEE projects are funded by NMEICT, MHRD, Government of India.
11:37 This tutorial was originally recorded by Prof Kannan Moudgalya in September 2015.

This is Kaushik Datta from IIT Bombay. Thanks for joining.

Contributors and Content Editors

PoojaMoolya