11-5240 JS DelayedCoker Refresh (1) (1)

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© 2014 Aspen Technology, Inc. AspenTech ®, aspenONE ®, the Aspen leaf logo, the aspenONE logo, and OPTIMIZE are trademarks of Aspen Technology, Inc. All rights reserved.11-5240-0214

Jump Start : Delayed Coker Model in Aspen HYSYS®

Petroleum Refining

A Brief Tutorial (and supplement to training and online documentation)Caleigh Holden, Product Management, Aspen Technology, Inc.


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Jump Start: Delayed Coker Model in Aspen HYSYS ® Petroleum Refining

Table of ContentsIntroduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Scope of this Document. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Example Cases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Petroleum Assay Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Properties Environment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Simulation Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Setting up the Delayed Coker . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Calibrating the Delayed Coker. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Setting up the Fractionation Column . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Combined Feed Ratio. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Additional Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11


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IntroductionThe new Delayed Coker model in Aspen HYSYS Petroleum Refining rigorously models the delayed coker unit in a refinery,

helping to optimize and debottleneck the process. This new feature allows users to:

• Calibrate the simulation model to match the behavior of the unit in the refinery• Predict coke and liquid product yields in scenarios away from calibration point

• Use the capabilities of Aspen HYSYS Petroleum Refining assay management to accurately characterize heavy crude

feed streams

This feature is a part of Aspen HYSYS Petroleum Refining, which allows users to seamlessly integrate with existing models

for Refinery simulation, making modeling easier and more accurate.

Scope of this DocumentThis document is intended as a “getting started” guide. It will cover the process of creating a delayed coking model,

including setting up a heavy crude feed with a petroleum assay, configuring a delayed coker unit operation, calibrating thecoker unit, and putting a recycle network together. It is not meant as a standalone reference document. We recommend

pairing this guide with a range of other resources, including:

• AspenTech knowledgebase items, training, and sample models available in aspenONE Exchange ®

• AspenTech Computer Based Training modules available from within Aspen HYSYS

• AspenTech support website (support.aspentech.com )

• AspenTech courseware available in on-line and in-person versions

• AspenTech Business Consultants

Knowledge of Aspen HYSYS V8 is assumed for this guide. Aspen HYSYS V8.4 needs to be installed to access the

functionality. If you do not know how to build a flow sheet in Aspen HYSYS, you should first consult reference material on

this subject. We recommend the following:

• Jump Start Guide: Getting Started with HYSYS V8

• AspenTech support website (support.aspentech.com )

• Aspen HYSYS training course

• Computer Based Training Module: Getting Started with Aspen HYSYS

http://support.aspentech.com/http://support.aspentech.com/http://support.aspentech.com/http://support.aspentech.com/http://support.aspentech.com/http://support.aspentech.com/http://support.aspentech.com/http://support.aspentech.com/


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Example CasesAn example Delayed Coking case ("DelayedCoker_RigorousColumn.hsc") is available in the Samples\Refining Cases

folder within Aspen HYSYS V8.4. This sample case can serve as a starting point for your modeling.

For this Jump Start Guide, we will be creating a similar model as the sample case mentioned above, but with a simplecomponent splitter in place of the rigorous column for the coker fractionator.

Petroleum Assay SetupThe first step in building any HYSYS flowsheet is setting up the Properties Environment. In this environment, the user

selects the components that will be used in the simulation and groups them into Component Lists. The user must also

select one or more Property Packages, which contain the thermodynamic properties and calculations used in the model.

The combination of a Component List and a Property Package is called a Fluid Package, and the user must define it

completely before they can move on to the Simulation Environment.

Properties Environment

When modeling a Delayed Coker in Aspen HYSYS, you are required to use a feed characterized with a petroleum assay.

Creating a petroleum assay will automatically set up the fluid package for you. First, we need to import the petroleum

assay into the properties environment using the “Petroleum Assays” button, as shown in Figure 1. When you open the

Assay Management tab, you can then find the “New Assay” button to the far right and select between these options, as

shown in Figure 2.

Figure 1. The Petroleum Assays button is the starting point for modeling a Delayed Coker in HYSYS


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Figure 2. The “New Assay” Button allows you to select the source of the Assay used in the Delayed Coker modelIn this example, we will import an existing assay file in .AFAM format, named “VacuumResid”, which contains assay data

from a typical vacuum column residual stream. This file can be found here:

http://www.aspentech.com/email/afam/VacuumResid.afam . After the file has been imported, you can verify stream

properties by checking the “Input Assay” and “Conventional Results” pages in the left hand Navigation Pane, as well as

viewing the distillation and property plots. When this input is complete, you can move on to the Simulation Environment.

Simulation Environment

The first step for setting up the Delayed Coker feed stream in the Simulation Environment is to add a Petroleum Feeder to

the flowsheet. The Feeder can be found in the Palette under the Refining tab, as shown in Figure 3. After the Feeder has

been added, it can be setup by double-clicking it. The Feed Assay should be set to the imported assay and the Product

Stream, which will be the initial input stream to the Delayed Coker and can be created within this page. In this case, it has

been named “VR Feed”, as seen in Figure 4.

Figure 3. Palette showing Petroleum Feeder among Refining units

http://www.aspentech.com/email/afam/VacuumResid.afamhttp://www.aspentech.com/email/afam/VacuumResid.afamhttp://www.aspentech.com/email/afam/VacuumResid.afamhttp://www.aspentech.com/email/afam/VacuumResid.afam


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Figure 4. Petroleum Feeder Setup, showing Feed Assay selection and Product Stream selection, in this case, “VR Feed”

After the Feeder has been setup, you can change the characteristics of this new stream. For the purposes of this guide, we

have set the temperature, pressure, and flow rate as shown in Figure 5.

Figure 5. Setup characteristics for Feeder output stream, which will become the initial Delayed Coker input


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Setting up the Delayed CokerAfter the feed stream has been set up, the Delayed Coker should be added to the flowsheet. It can be found in the Refining

tab of the Palette, as shown in Figure 6.

Figure 6. Delayed Coker model in the Refining tab of the Palette

After the Delayed Coker model is added to the flowsheet, it will need to be setup

starting with streams. In an actual refinery, there is usually a complicated recycle

scheme. For easier model convergence, we are going to first solve the reactor feeding

the vacuum column residue stream directly into the coker. In a later part of this jump

start guide, we will show you how to set up the recycle scheme. The output stream

from the Feeder, which we named “VR Feed”, should be connected to the Delayed

Coker as the “Crude Feed to Heater”. The “Coker Drum Effluent” can be created within

this window, and in this case we’ll call it “Coker Effluent”. The Coker is then ready for

the basic Input setup, which we have done using the numbers shown in Figure 7.

Figure 7. Setup for the Delayed Coker, including connected streams and model characteristics

When all the input is complete, the Delayed Coker should converge. Within the model window under the Design tab, you

can find Product Yields, Product Properties, and Tuning Factors. It is important to note that during the initial setup of theDelayed Coker, we are using default Tuning Factors which will later change when the model is calibrated. Under the Solver tab,

you can also see the Solver Settings. Users having convergence issues can increase the number of iterations or change

tolerance and step size to converge the model.


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Calibrating the Delayed CokerAfter the Delayed Coker has been solved, it is necessary to calibrate it. As mentioned previously, the model this far has

been solved using default factors which are not plant-specific. To calibrate the model, open the “Calibrate” tab within the

Delayed Coker window. The first page on the left will ask for specific cuts if it’s different from the value set by default. In

the second and third pages, the user should enter information about the composition of the light and heavy end cuts.

Example data is shown in Figures 8 and 9 below.

Figure 8. Example of l ight end calibration data for Aspen HYSYS Delayed Coker model

Figure 9. Example of heavy end calibration data for Aspen HYSYS Delayed Coker model


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In addition to cuts and heavy and light end data, you also need to enter drum temperature and coke sulfur percentage.

When all of this data has been entered, the “Calibrate” button under the “Calibration Targets” ply will become available

and the system will be ready to calibrate, as shown in Figure 10. Once the calibration is successful, the option to “Transfer

to Simulation” will also become available. This step transfers the calibration results to the HYSYS model and the button

must be clicked before the data is transferred.

Figure 10. After all the calibration data has been entered into the model, the option to “Calibrate” the Delayed Coker will become available andafter a successful calibration, the “Transfer to Simulation” button will become available


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Setting up the Fractionation ColumnOnce the calibration is complete and the tuning parameters are applied to the simulation, the Delayed Coker model needs

to be connected to a Fractionation Unit for product separation. In the actual process, the bottoms stream from this column

is the inlet into the Delayed Coker, so it is necessary to change the model accordingly after calibration. In this example, for

the sake of length, we will add a simple Fractionation Column. The model is available in the palette under the Column tab

as a Component Splitter, as shown in Figure 11.

Figure 11. The addition of the Fractionation Column, available as a Component Splitter under the Columns tab in the Palette

Once the Fractionation Column is added, the feed streams must be connected. The connection between the VR Feed and

the Delayed Coker must be broken, as both this stream and the Coker Effluent will be the inlet streams into the column. By

double-clicking the Fractionation Column, you can set the Inlet, create Overhead and Bottoms Outlets, and add an Energy

Stream (in this case, “Q”). At first, only the VR Feed should be connected to the column. The overhead outlet streams of

the column in this case, include the Fuel Gas, Liquefied Gases, Naphtha, and Gas Oils, while the bottoms outlet will be fed

to the coker, as shown in Figure 12.

Figure 12. Streams being connected to the Fractionation Column, including the VR Feed, overhead outlets, and bottoms outlet


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After all the streams have been connected, more data needs to be entered for the column to solve. The temperature and

pressure of the overhead streams need to be determined in the “Parameters” ply, and the cut points for the product

streams must be added in the “TBP Cut Point” ply. At the end of this process, the column should converge.

Connect the bottoms outlet of the fractionation unit to the Delayed Coker as the feed. The model should converge. The

“Coker Effluent” stream is essentially a recycle stream and will be treated as one in this case. The converged reactor setup in the previous steps is a good starting point for the recycle calculations, and will help converge the final solution

quickly. Therefore, before connecting it to the Fractionation Column, we will add a Recycle block, which can be found

under the “Common” tab in the Palette, as shown in Figure 13.

Figure 13. Location of the Recycle block in the Palette

The “Coker Effluent” stream should then be connected to the Recycle block and a new stream, which we’ve called

“Coker Product” stream, should be created as the Recycle outlet. After the recycle is set up, the "Coker Product" stream

can be connected to the Fractionation Unit, and the full model should solve. The final flowsheet should look like the one

in Figure 14.


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Figure 14. Completed flowsheet for a delayed coking processCombined Feed Ratio

Combined Feed RatioThe combined feed ratio (CFR), also known as recycle ratio, is the ratio of the flow into the coker furnace to the total

Vacuum Resid feed to the entire unit. In the above flowsheet, this is the ratio of the “Bottoms to Coker” stream to the “VR

Feed” stream. In a typical refinery, this number will be greater than 1 because the heavier portion of the coker product

comes out of the bottom of the column with the fresh feed.

In the Aspen HYSYS Delayed Coker model, the user is required to enter this value into the input page. When calibrating

the model, this value is used for product flowrate calculations and for property calculations. For simulation, however, this

value is only used for property prediction and does not affect the flowrates of streams in the Aspen HYSYS flowsheet. For

the most accurate model, the CFR should be consistent with the flowrates in the Aspen HYSYS flowsheet, but it is not a

requirement for the model to solve.


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Additional ResourcesPublic Website:

www.aspentech.com/products/aspen-refsys-delayed-coker.aspx

Aspen Online Training:

www.aspentech.com/products/aspen-online-training

On-demand Short Presentation:

Intro to HYSYS Petroleum Refining V8.4

www.brainshark.com/aspentech1/reactors-assays-v84

Jump Start Tutorial Series:

Jump Start: Aspen HYSYS V8.0

www.aspentech.com/JumpStart_HYSYSV8/

http://www.aspentech.com/products/aspen-refsys-delayed-coker.aspxhttp://www.aspentech.com/products/aspen-online-traininghttps://www.brainshark.com/aspentech1/reactors-assays-v84https://www.brainshark.com/aspentech1/reactors-assays-v84http://www.aspentech.com/JumpStart_HYSYSV8/http://www.aspentech.com/JumpStart_HYSYSV8/http://www.aspentech.com/products/aspen-refsys-delayed-coker.aspxhttp://www.aspentech.com/products/aspen-online-traininghttps://www.brainshark.com/aspentech1/reactors-assays-v84http://www.aspentech.com/JumpStart_HYSYSV8/


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