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Gas Gathering 1

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Gas Gathering

© 1999 AEA Technology plc - All Rights Reserved.Gas 6_1.pdf

2 Gas Gathering

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WorkshopIn this example, a gas gathering system located on varied terrain is simulated using the steady state capabilities of HYSYS. The following figure shows the physical configuration of this system superimposed on a topographic map. The system consists of four wells distributed over an area of approximately 2.0 square km, connected to a gas plant via a network of pipelines.

The gas in this case is varied, both sour and sweet gas are being combined in the pipeline, as well as a gas condensate mixture. A Mixer combines all of the incoming gas streams from the outlying wells into one common header. Flowlines extending from this central site to each of the individual wells are modelled in HYSYS using the Pipe Segment operation. Since the plant is located in an area with mixed terrain, the elevation changes, must be accounted for in the Pipe Segments.

Additional Mixer operations are used to model mixing points where flows from remote wells are combined in common lines.

Fast Track to page 6.

Gas Gathering 3

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Learning ObjectivesOnce you have completed this module, you will be able to:

• Use the Pipe Segment in HYSYS to model pipelines

Prerequisites• Adding Streams and Operations

Process OverviewPipe Diameters for each of the branches are:

Schedule 40 steel pipe is used throughout and all branches are buried at a depth of 1m (3 feet). All pipes are uninsulated.

Elevation data for each of the branches are provided in the following table. Branches that traverse undulating terrain have been subdivided into a number of segments with elevation points assigned at locations where there is a significant slope change. Such locations in the network

Pipe Branch Diameter

Branch 1 76.2 mm (3")

Branch 2 76.2 mm (3")

Branch 3 76.2 mm (3")

Branch 4 101.6 mm (4")

Branch 5 76.2 mm (3")

Branch 6 152 mm (6")

Branch 7 152 mm (6")

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are labeled on the schematic diagram with the elevation value in italics.

Branch Segment Lengthmeter (feet)

Elevationmeter (feet)

Elevation Changemeter (feet)

Branch 1 GasWell 1 639 (2095)

1 150 (500) 645 (2110) 6 (15)

2 125 (410) 636.5 (2089) -6.5 (-21)

3 100 (325) 637 (2090) 0.5 (1)

Branch 2 GasWell 2 614 (2015)

1 200 (665) 637 (2090) 23 (75)

Branch 3 GasWell 3 635.5 (2085)

1 160 (525) 648 (2125) 12.5 (40)

2 100 (325) 634 (2080) -14 (-45)

3 205 (670) 633 (2077) -1 (-3)

Branch 4 Branch 1 & 2

637 (2090)

1 355 (1165) 633 (2077) -4 (-13)

Branch 5 GasWell 4 632.5 (2075)

1 180 (590) 625 (2050) -7.5 (-25)

2 165 (540) 617 (2025) -8 (-25)


633 (2077)

1 300 (985) 617 (2025) -16 (-52)


617 (2025)

1 340 (1115) 604 (1980) -13 (-45)

Process Overview

6 Gas Gathering

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Building the SimulationThe gas field will be modelled using the Peng Robinson property package. The Fluid Package needs to contain the components from Module 1, Getting Started as well as the Oil Components from the Gas Chromatograph Module.

Rather than adding the components and the oil again, open the case from Module 5 (containing the four Gas Well streams).

The following components should appear in the Fluid Package, N2, H2S, CO2, C1, C2, C3, i-C4, n-C4, i-C5, n-C5, C6, C7+*, H20, NBP[0]78*, NBP[0]162*, NBP[0]245*, NBP[0]318*, NBP[0]431*

The four streams should have the following values:

Adding the Pipe SegmentsThe Pipe Segment is used to simulate a wide variety of piping situations ranging from single/multiphase plant piping with rigorous heat transfer estimation, to large capacity looped pipeline problems. It offers the pressure drop correlations developed by Gregory, Aziz, and Mandhane, and Beggs and Brill. A third option, OLGAS, is also available as a gradient method. Four levels of complexity in heat transfer estimation allow you to find a solution as rigorous as required while allowing for quick generalized solutions to well-known problems.

The Pipe Segment offers three calculation modes: Pressure Drop, Flow, and Length; the appropriate mode will automatically be selected depending on the information supplied. In order to solve the pipe, you must supply enough information to completely define both the material balance and energy balance.

Open case Optional6.hsc

Start adding the pipe segments.

If you are using Field units, the oil components will have different names, corresponding to the different NBP.

GasWell 1 GasWell 2 GasWell 3 GasWell 4

Temperature °C (°F)

40 (105) 45 (115) 43 (110) 35 (95)

Pressure kPa (psia)

4135 (600) 3450 (500)

Flowkgmole/h (lbmole/hr)

425 (935) 375 (825) 575 (1270) 545 (1200)

Getting Started 7

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5. Select the library components N2, H2S, CO2, C1, C2, C3, i-C4, n-C4, i-C5, n-C5, C6, and H2O.

6. Select the Hypothetical radio button under Add Comps to add a hypothetical component to the Fluid Package.

A hypothetical component can be used to model non-library components, defined mixtures, undefined mixtures or solids. We will be using a hypothetical component to model the components in the gas mixture heavier than hexane. To create this hypothetical component, select the Quick Create A Hypo Comp button.

When you use the Quick Create a Hypo Comp button, HYSYS adds a hydrocarbon class hypo by default. If you want to add a hypo from another class, push the Quick Access to Hypo Mgr button and then in the view that appears, push the View Group button. This will open the Tabular Hypothetical Input Manager, where you can add non-hydrocarbon class hypotheticals.

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7. On the ID tab of the hypo component view, supply the Component Name, C7+.

In this case, we do not know the structure of the hypothetical component and we are modelling a mixture so the Structure Builder will not be used.

HYSYS always places an ‘*’ after a hypo name so it can be distinguished from library components.

Getting Started 9

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8. Move to the Critical tab. The only property supplied by the lab for the C7+ component is the Normal Boiling Pt. Enter a value of 110°C (230°F). Press the Estimate Unknown Props button to estimate all the other properties and fully define the hypothetical component.

9. When the hypo has been defined, return to the Fluid Package by closing the Hypothetical Component C7+* view.

10. Add the hypo to the Current Component List by selecting it in the Hypo Components group and then pressing the Add Hypo button.

The minimum information required for defining a hypo is the Normal Boiling Point or the Density and Molecular Weight.

You can use the Sort List button to order the Component List.

Getting Started 15

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Adding a Stream from the Menu Bar

To add a stream using the <F11> hot key:

1. Press the <F11> hot key. The stream property view appears. If the stream property view is not displayed, double click on the newly created stream to bring up the property view.

Highlight the Stream Name cell. Change the stream name by typing in a new name:

2. Change the stream name to GasWell 1.

3. Click on the Check button, or press Enter.

Getting Started 17

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6. Enter the following compositions

7. Press the OK button when all the mole fractions have been entered.

8. Close the Stream property view.

For this Component... Enter this Mole Fraction...

N2 0.0002

H2S 0.0405

CO2 0.0151

C1 0.7250

C2 0.0815

C3 0.0455

i-C4 0.0150

n-C4 0.0180

i-C5 0.0120

n-C5 0.0130

C6 0.0090

C7+ 0.0252

H2O 0.0000

If there are <empty> values either enter 0 or press the Normalize button. The stream is not fully defined until all composition values have a numerical input.

18 Getting Started

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Adding a Stream from the WorkbookTo open or display the Workbook, press the Workbook button on the Button Bar.

1. Enter the stream name, GasWell 2 in the **New** cell.

2. Double click on the Molar Flow cell and enter the following compositions:

3. Click the OK button to close the Input Composition for Stream dialog box.

Adding a Stream from the Object Palette

1. If the Object Palette is not open on the Desktop, press the <F4> hot key to open it.

2. Double click on the Material Stream button. The Stream property view displays.

3. Change the name of the stream to GasWell 3.

4. Double click on Molar Flow.

Workbook button


N2 0.0025

H2S 0.0237

CO2 0.0048

C1 0.6800

C2 0.1920

C3 0.0710

i-C4 0.0115

n-C4 0.0085

i-C5 0.0036

n-C5 0.0021

C6 0.0003

C7+ 0.0000

H2O 0.0000

Material Stream button (Blue)

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5. Enter the following stream compositions:

Saving your CaseYou can use one of several different methods to save a case in HYSYS.

• From the File menu select Save to save your case with the same name.

• From the File menu select Save As to save your case in a different location or with a different name.

• Press the Save button on the Button Bar to save your case with the same name.


N2 0.0050

H2S 0.0141

CO2 0.0205

C1 0.5664

C2 0.2545

C3 0.0145

i-C4 0.0041

n-C4 0.0075

i-C5 0.0038

n-C5 0.0037

C6 0.0060

C7+ 0.0090

H2O 0.0909

Save your case often to avoid losing information.

Save Button

Save your case!

Getting Started 31

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Printing an Individual Stream Datasheet

To print the datasheet for an individual Stream, Object Inspect the stream property view title bar and follow the same procedure as with the Workbook.

Finishing the SimulationThe final step in this section is to add the stream information necessary for the case to be used in future modules.

Add the following temperature, pressure and flowrate to the streams:

Temperature Pressure Flowrate

GasWell 1 40°C (105°F)

4135 kPa (600 psia)

425 kgmole/h

(935 lbmole/hr)

GasWell 2 45°C(115°F)

3450 kPa(500 psia)

375 kgmole/h (825 lbmole/hr)

GasWell 3 40°C(105°F)

575 kgmole/h(1270 lbmole/hr)

Save your case!

Oil Characterization 5

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Building the SimulationBefore you can start the actual characterization process, you must:

• Select a Property Package• Add any non-oil components, specifically the Light Ends that

are to be used in the characterization process.

Defining the Simulation BasisFor this module, you will be building on the case you started in Module 1.

1. Open the case you saved at the end of Module 1.

2. Press the Basis Environment button to return to the Basis Environment.

3. Go to the Oil Manager tab and press the Enter Oil Environment button. You could also press the Oil Environment button on the Button Bar. The Oil Characterization view displays.

Basis Environment Button

Oil Environment Button

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Oil CharacterizationThe petroleum characterization in HYSYS accepts different types of information about the oil. The more information you can supply about your sample, the more accurate the representation will be.

There are three steps involved in characterizing any oil in HYSYS:

1. Characterize the Assay

2. Generate Pseudo Components

3. Install the Oil in the Flowsheet

Characterize the Assay

The assay contains all of the petroleum laboratory data, boiling point curves, light ends, property curves and bulk properties. HYSYS uses the supplied Assay data to generate internal TBP, molecular weight, density and viscosity curves, referred to as Working Curves.

Assay Types

Accurate volatility characteristics are vital when representing a petroleum fluid in your process simulation. HYSYS accepts the following standard laboratory analytical assay procedures.

• True Boiling Point (TBP) - Performed using a multi-stage batch fractionation apparatus operated at relatively high reflux ratios. TBP distillations conducted at atmospheric or vacuum conditions are accepted by the characterization.

• ASTM D86 - Distillation employing batch fractionation but conducted using non-refluxed Engler flasks. Generally used for light to medium petroleum fluids. HYSYS can correct for barometric pressure or cracking effects. You must provide the data on a liquid volume basis.

• D1160 distillation - Distillation employing batch fractionation but conducted using non-refluxed Engler flasks. Generally used for heavier petroleum fluids. Curves can be given at atmospheric pressure or corrected for vacuum conditions. You must provide the data on a liquid volume basis.

• D86_D1160 - This is a combination of the D86/D1160 distillation data types. You can correct for thermal cracking and enable vacuum distillation for sub-atmospheric conditions. You must provide data on a liquid volume basis.

• ASTM D2887 - Simulated distillation analysis from chromatographic data. Reported only on a weight percent basis at atmospheric conditions.

The Minimum amount of information that HYSYS requires to characterize an oil:

• a laboratory distillation curve

• two of the following bulk properties: Molecular Weight, Density, or Watson K Factor

For all Distillation Curves, you are required to enter at least five data points.


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• Equilibrium Flash Vaporization (EFV) - Involves a series of experiments at constant atmospheric pressure, where the total vapour is in equilibrium with the unvaporized liquid.

• Chromatographic Analysis - A gas chromatograph analysis of a small sample of completely vaporized oil, analyzed for paraffin, aromatic and naphthenic hydrocarbon groups from C6 to C30. Chromatographic analyses may be entered on a mole, mass or liquid volume basis.

Light Ends

Light Ends are defined as pure components with low boiling points. Components in the boiling range of C2 to n-C5 are most commonly of interest.

HYSYS provides three options to account for Light Ends:

• Ignore - HYSYS will characterize the Light Ends portion of your sample as pseudo components. This is the least accurate method and as such, is not recommended.

• Auto Calculate - Select this when you do not have a separate Light Ends analysis but you want the low boiling portion of your assay represented by pure components. HYSYS will only use the pure components you have selected in the Fluid Package.

• Input Composition - Select this when you have a separate Light Ends assay and your petroleum assay was prepared with the Light Ends in the sample. HYSYS will provide a form listing the pure components you selected in the Fluid Package. This is the most accurate method of representation.

Bulk Properties

Bulk Properties for the sample may also be supplied. The bulk properties are optional if a distillation curve or chromatograph have been supplied.

• Molecular Weight - This is the Molecular Weight of the bulk sample. It must be greater than 16.

• Mass Density - The mass density must be between 250 and 2000 kg/m3.

• Watson (UOP) K Factor - This must be between 8 and 15.• Bulk Viscosity’s - Given at two reference temperatures,

typically 37.78 C and 98.89 C (100 F and 210 F).

• The units for density can be mass density, API or specific gravity, chosen from the drop down list in the Edit Bar

• The Watson K Factor is an approximate index of paraffinicity. K = (Mean Avg BP)1/3/(sp gr 60F/60F)


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Physical Property Curves

HYSYS accepts different types of physical property curves

• Molecular Weight Curve• Density Curve• Viscosity Curve

Physical property analyses are normally reported from the laboratory using one of the following two conventions.

• An Independent assay basis, where a common set of assay fractions is NOT used for both the distillation curve and the physical property curve

• A Dependent assay basis, where a common set of assay fractions is utilized for both the distillation curve and the physical property curve.

As you supply more information to HYSYS, the accuracy of the Petroleum Characterization increases. Supplying any or all of the bulk molecular weight, bulk density, or bulk Watson K factor will increase the accuracy of your pseudo component properties. You can also supply laboratory curves for molecular weight, density, and/or viscosity, which will increase the accuracy further.

Adding Assay Data

1. On the Assay tab of the Oil Characterization view, select the Add button to display the Input Data tab of the Assay view.

2. In the Name cell, change the assay name to Res-Fluid.

3. For the Bulk Props cell, use the drop down menu to select Used.

4. From the Data Type drop down, select Chromatograph.

5. Once the correct Data Type is chosen, a third cell should appear. This is the Light Ends cell; use the drop down menu to select Input Composition.


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When steps 1 - 5 are completed, the view should look something like this.

6. Select the Light Ends radio button in the Input Data group. Specify the Light Ends Basis as Mole % and enter the following data:

You need to enter the light components in the Fluid Package for them to be available to the Oil Manager.

For this Component... Enter this Mole Percent...

N2 0.98

H2S 0.00

CO2 0.37

C1 41.83

C2 8.87

C3 7.11

i-C4 1.47

n-C4 3.75

i-C5 1.25

n-C5 1.63

n-C6 0.00

H2O 0.00


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7. Select the Paraffinic radio button and specify the Basis as Mole. Enter the following data.


Hexane (C6) 0.0268

Heptane (C7) 0.0371

Octane (C8) 0.0348

Nonane (C9) 0.0231

Decane (C10) 0.0240

Undecane (C11) 0.0183

Dodecane (C12) 0.0142

Tridecane (C13) 0.0141

Tetradecane (C14) 0.0113

Pentadecane (C15) 0.0099

Hexadecane (C16) 0.0074

Heptadecane (C17) 0.0082

Octadecane (C18) 0.0062

Nonadecane (c19) 0.0049

Eicosane (C20) 0.0046

Heneicosane (C21) 0.0039

Docosane (C22) 0.0036

Tricosane (C23) 0.0032

Tetracosane (C24) 0.0027

Pentacosane (C25) 0.0024

Hexacosane (C26) 0.0021

Heptacosane (C27) 0.0020

Octacosane (C28) 0.0018

Nonacosane (C29) 0.0016

Triconane Plus 0.0133


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8. Select the Aromatic radio button, and enter the following mole fractions.

9. Enter the following data for the Naphthenic components.

10. Select the Bulk radio button to enter the Bulk information.

11. The Molecular Weight is 79.6 and the Specific Gravity (Density) is 0.6659 SG_60/60api.

12. Once you have entered all of the data, press the Calculate button. The status message at the bottom of the Assay view will display Assay Was Calculated.

Once the Assay is calculated, the working curves are displayed on the Working Curves tab. The working curves are regressed from the Assay input. The calculation of the Blend is based on these working curves.

13. Close this view to return to the Oil Characterization view. You should still be on the Assay tab of the view.

Notice that all of the buttons on the view are now accessible.


Benzene (C6H6) 0.0004

Toluene (C7H8) 0.0015

EBZ, p+m-Xylene (C8H10) 0.0070

o-Xylene (C8H10) 0.0028

1,2,4 TriMethylBenzene (C9H12) 0.0028


Cyclopentane (C5H10) 0.0002

MethylCycloPentane (C6H12) 0.0106

Cyclohexane (C6H12) 0.0050

MethylCycloHexane (C7H14) 0.0156

Specific Gravity is added in the Mass Density cell.

Just as with Fluid Packages, Assays can be Imported and Exported to be used in different cases.


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Pseudo Component Generation/Blending the Oil

The Cut/Blend characterization in HYSYS splits the internal working curves for one or more assays into pseudo components. The Blend tab of the Oil Characterization view provides two functions, Cutting the Oil into Pseudo Components and Blending two or more Assays into one set of pseudo components.

Cut Ranges

You have three choices for the Cut Option Selection:

• Auto Cut - HYSYS cuts the assay based on internal values

• User Points - You specify the number of pseudo components required. HYSYS proportions the cuts according to an internal weighting scheme.

• User Ranges - You specify the boiling point ranges and the number of cuts per range.

Range Cuts

37.78 - 425 oC (100 - 800 oF) 28 (4 per 37.78 oC/100 oF)

425 - 650 oC (800 - 1200 oF) 8 (2 per 37.78 oC/100 oF)

650 - 870 oC (1200 - 1600 oF) 4 (1 per 37.78 oC/100 oF)

Cutpoint Range Internal Weighting

IBP - 425 oC (IBP - 800 oF) 4 per 37.78 oC/100 oF

425 - 650 oC (800 - 1200 oF) 2 per 37.78 oC/100 oF

650 oC - FBP (1200 oF - FBP) 1 per 37.78 oC/100 oF


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Cutting the Assay

Once the Assay has been calculated, you can cut the Assay into individual pseudo components.

1. Move to the Cut/Blend tab of the Oil Characterization view. Select the Add button to create a new Blend.

2. In the Name cell, change the name from the default, Blend-1 to Res-Fluid.

3. From the list of Available Assays (there should only be one), select Res-Fluid and press the Add button. This will add the Assay to the Oil Flow Information table and a Blend (Cut) will automatically be calculated. The Blend is calculated using the default Cut Option, Auto Cut.

4. Instead of using the default Auto Cut option, change the Cut Option Selection to User Points and change the Number of Cuts to 5.

The results of the calculation can be viewed on the Tables tab of the Blend view.

Installing the Oil in the Flowsheet

The final step of the characterization is to transfer the pseudo component information into the Flowsheet.

1. Move to the Install Oil tab of the Oil Characterization view.

2. The Blend, Res-Fluid appears in the Oil Install Information group.

3. In the Stream Name column, enter the name, GasWell 4, to which the oil composition will be transferred.

HYSYS will assign the composition of your calculated Oil and Light Ends into this stream, completing the characterization process.

Return to the Basis Environment by pressing the Return to Basis Environment button.

When you return to the Basis Environment, the pseudo components that you have generated in the Oil Characterization are placed in the current Fluid Package. You can View the Fluid Package and examine the individual hypothetical components which make up your oil.

Note that reducing the Number of Cuts will increase simulation speed, but it may have a negative effect on simulation accuracy.

Save your case!


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Composite Plot Tab

The Composite Plot tab allows you to visually check the match between the input assay data and the calculated property curves. The choice for the graphical comparison is made from the Property drop down list.

• TBP or ASTM Distillation Curve• Molecular Weight Curves• Mass Density Curves• Viscosity Curves• Any User Property Curve

Viewing the Stream in the Simulation

Leave the Oil Environment, return to the Basis Environment, and enter the Simulation Environment. Move to the Workbook to view the stream that you created, GasWell 4. You can view the stream composition on the Compositions tab of the WorkBook.

If you decided that some of the pseudo components parameters need to be recalculated, you can return to the Oil Environment at any time to make changes.

The following parameters need to be added to the stream GasWell 4:

In this cell... Enter...

Temperature 35°C (95°F)

Flowrate 545 kgmole/h (1200 lbmole/hr)

Save your case!

Gas Gathering 7

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In this simulation, we will be using seven individual Pipe Segment operations in the gathering system. In addition, each Pipe Operation may contain multiple segments to represent the various elevation rises and drops.

Adding the first Pipe Segment1. Double click on the Pipe Segment button.

Connections page

On the Connections page, the Feed, Product and Energy stream connections are made.

2. Complete the Connections page as shown below:

Pipe Segment Button

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Parameters page

On this page, you can select the gradient method which will be used for Two-Phase (VL) flow calculations. The options are:

• Gregory Aziz Mandhane • Beggs and Brill • OLGAS

For all of the pipes in this example, use the Beggs and Brill correlation for two phase flow.

The Pressure Drop for the pipe can be supplied on the Parameters page. In this example, it will be left empty and calculated.

Rating tab

Dimensions page

On the Sizing page, you construct the length-elevation profile for the Pipe Segment. Each pipe section and fitting is labeled as a segment. To fully define the pipe sections segments, you must also specify pipe schedule, diameters, pipe material and a number of increments.

The first pipe, Branch 1 is broken into three segments.

3. Add the first segment to the pipe unit operation by pressing the Add Segment button. Specify the following information for the segment.

4. To specify the diameter, press the View Segment button.

5. Select Schedule 40 as the Pipe Schedule.

6. From the Available Nominal Diameters group, select 76.20 mm (3 inch) diameter pipe and press the Specify button. The Outer and Inner Diameter will be calculated by HYSYS.

7. Use the default Pipe Material, Mild Steel and the default Roughness, 4.572e-5 m.

For single phase streams, the Darcy equation is used for pressure drop predictions.

Horizontal pipe sections have an Elevation of 0. Positive elevation indicates that the outlet is higher than the inlet.


Fitting/Pipe Pipe

Length 150 m (500 ft)

Elevation Change 6 m (15 ft)

HYSYS contains a database for three pipe schedules, 40, 80 and 160.

Gas Gathering 9

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8. Two more segments are needed to complete the branch.

When all three segments have been added and defined, the view should look like this:

The Pipe Segment is not yet able to solve because we have not specified any information about the heat transfer properties of the pipe.

In this cell... Enter... Enter...

Segment 2 3

Fitting/Pipe Pipe Pipe

Length 125 m (410 ft) 100 m (325 ft)

Elevation -6.5 m (-21 ft) 0.5 m (1 ft)

Schedule 40 40

Nominal Diameter 76.2 mm (3 inch) 76.2 mm (3 inch)

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Heat Transfer page

On this page, you select the method that HYSYS will use for the heat transfer calculations.

You have the option of specifying the heat transfer information By Segment or Overall.

• By Segment - you specify the Ambient Temperature and HTC (Heat Transfer Coefficient) for each segment that was created on the Dimensions page.

• Overall - one of four heat transfer methods will be applied to the whole pipe segment.

• Duty Method - if the Overall heat duty of the segment is known, the energy balance can be calculated immediately. Each increment is assumed to have the same heat loss.

• Stream Temperatures - if both inlet and outlet and ambient temperatures are specified, a linear profile is assumed and the overall heat duty can be calculated.

• Overall Heat Transfer Coefficient Specified - if the overall HTC and Ambient Temperature are known, then rigorous heat transfer calculations are performed on each increment of the pipe.

• Heat Transfer Coefficient Estimation - the overall HTC can be found from its component parts.•Inside Film Convection•Outside Conduction/Convection•Conduction through Insulation

For all pipes in this simulation, use Overall and the Heat Transfer Coefficient Estimation method.

9. Supply an Ambient Temperature of 5°C (40°F)

10. In the Heat Transfer Coefficient Estimation group, provide the following information:

Inside

Outside - everything is default

Gas Gathering 11

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Conduction- everything is default, except the insulation thickness which must be changed to zero.

Completing the SimulationNow add the remaining unit operations to your case.

1. Add two Pipe Segments with the following values:

What is the outlet pressure of Branch 1? __________Fast Track to page 15


Connections

Name Branch 2

Feed GasWell 2

Product B2 Out

Energy B2-Q

Dimensions

Segment 1


Elevation 23 m (75 ft)

Nominal Diameter 101.6 mm (4 in)

Heat Transfer

Estimate Inner, Outer and Conduction HTC

Remember for all pipes in this example, use Schedule 40, an Ambient Temperature of 5°C.

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Connections

Name Branch 3

Feed GasWell 3

Product B3 Out

Energy B3-Q

Dimensions

Segment 1


Elevation 12.5 m (40 ft)


Segment 2


Elevation -14 m (-45 ft)


Segment 3




Heat Transfer


Gas Gathering 13

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2. Add a Mixer with the following information:

3. Add two Pipe Segments to your case with the values provided in the following tables.


Connections

Name Junction 1

Feed B1 Out, B2 Out

Product J1 Out

Parameters

Pressure Assignment Set Outlet to Lowest Inlet


Connections

Name Branch 4

Feed J1 Out

Product B4 Out

Energy B4-Q

Dimensions

Segment 1




Heat Transfer


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4. Add a second Mixer to your case.


Connections

Name Branch 5

Feed GasWell 4

Product B5 Out

Energy B5-Q

Dimensions

Segment 1


Elevation -7.5 m (-25 ft)


Segment 2




Heat Transfer



Connections

Name Junction 2

Feed B3 Out, B4 Out

Product J2 Out

Parameters

Pressure Assignment Equalize All

What is the pressure of GasWell 3? __________

How was this calculated? __________

Gas Gathering 15

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5. Add a Pipe Segment to your case.

6. Add a Mixer to the simulation.


Connections

Name Branch 6

Feed J2 Out

Product B6 Out

Energy B6-Q

Dimensions

Segment 1




Heat Transfer


Continue with step 6.


Connections

Name Junction 3

Feed B5 Out, B6 Out

Product J3 Out

Parameters

Pressure Assignment Equalize All

What is the pressure of GasWell 4? __________

How was this calculated? __________

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7. Add another Pipe Segment to the simulation with the following values:

Optional:


Connections

Name Branch 7

Feed J3 Out

Product B7 Out

Energy B7-Q

Dimensions

Segment 1




Heat Transfer


Save your case!

Convert your case to a template and save!

Gas Gathering 19

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Exploring with the Simulation

Exercise 1The flow of gas being produced by GasWell 2 increases to about 1000 kgmole/h (2200 lbmole/hr). Can the existing pipeline handle this increased flow. If not, what size pipe will be needed in Branch 2. Do any other parts of the pipeline need to be changed?

ChallengeYou instruct your summer student, Peter Reynolds to go out to the field and measure the temperature and pressure of the gas that is being delivered to the Gas Plant. He reports that the temperature is 38 °C (100 oF) and the pressure is 7457 kPa (1080 psia). Using your HYSYS simulator, what do you find the pressure of each of the Gas Wells to be?

Hint: you will have to make some changes to the simulation into order for it to solve completely.

gas gathering 1 gas gathering - ferdowsi university of...

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