WinProp
Tutorial
Dry Gas, Wet Gas, Gas Condensate,
Volatile Oil, Black Oil, and Heavy Oil
Prepared for: Petroleum Institute Abu Dhabi
Instructor: Amir Moradi
December 2011
Table of Contents
Exercise 1 – Base Models of Five Different Fluid Types ........................ 3
Basic Setup and Dry Gas Fluid Model Creation .................................................................................. 3
Additional Exercises ............................................................................................................................. 19
Exercise 2 – Determination of MMP and MME .................................... 24
Addition of Injection Streams and Calculations ................................................................................ 24
Multi-Contact Miscibility Minimum Pressure Calculation .............................................................. 28
Exercise 3 – Creation of Raleigh Black Oil ........................................... 30
Setup of WinProp model with Plus Fraction Splitting ...................................................................... 30
Defining Calculations and Experimental Values ............................................................................... 32
Using Regression to Match WinProp model to Laboratory Results ................................................ 36
Matching Viscosity in WinProp to Laboratory Values ..................................................................... 39
Defining an IMEX Fluid Model Output ............................................................................................. 41
Exercise 4 – Heavy Oil Fluid Model ...................................................... 46
Setup of WinProp model with Plus Fraction Splitting ...................................................................... 46
Matching of WinProp Model to Laboratory Results ......................................................................... 48
Matching of WinProp Model Viscosity to Laboratory Viscosity...................................................... 52
Creating a STARS PVT Model from WinProp .................................................................................. 56
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Exercise 1 – Base Models of Five Different Fluid Types
The purpose of this exercise is to utilize WinProp to build 5 different types of fluid models. A
general understanding of the interface and associated windows should be gained in the process of
creating fluid models for Dry Gas, Wet Gas, Gas Condensate, Volatile Oil, and Black Oil cases.
Basic Setup and Dry Gas Fluid Model Creation
1.
Double click on the WinProp icon in the Launcher and open the WinProp interface.
Please note that this course’s images and descriptions are based on WinProp
version 2011.10 or newer.
2.
Open the Titles/EOS/Units form and write “Dry Gas” in the Comment Line section and
the Title Line 1 section.
When inputting data for the other fluid models (Wet Gas, Gas Condensate,
etc.) input the appropriate name for the model.
Select PR 1978 as the equation of state to be used in characterizing the fluid model,
select “Psia & deg F” as the units and Feed as "Mole".
Figure 1: Title/EOS/Units Screen
3.
Go to Component Selection/Properties form and insert the library components in the
following order:
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CO2, N2, C1, C2, C3, IC4, NC4, IC5, NC5, and FC6.
To do this click on the Ins Lib button (Insert Library Component) and select the library
components you wish to insert (select multiple components at a time by holding Shift or
Control) then click on the right arrow to add the components (Figure 3), and click OK
to finalize.
If you need to inset a component you missed (Figure 4), select the component above
where you want to inset the new component (Figure 5), and then use Ins Lib again to
insert the new component directly under the current selection. (*Note: This feature is
not working properly in Windows. It works only if you insert missing C2H6 when
cursor is at CO2 location. It also works if you select one additional component).
Figure 2: How to Insert Library Components
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Figure 3: Selection of Components
Figure 4: Component Definition Missing C2 Compound
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Figure 5: Select CH4 then use Ins Lib to insert the missing C2H6 Compound
immediately below.
Note on Order:
The order of these components only matters in the input of compositions. In these
examples the compositions will be copied from an Excel file in this order which
implies that the order will be important.
4.
+
In all cases, except “Dry Gas”, also characterize the C7 fraction with a single
pseudocomponent by inserting a user defined component (Figure 6).
In the Component Selection/Properties form select the last component on the list, then
click on the Ins Own button. Click the New Row button, and enter the information for
component name, specific gravity (SG) and molecular weight (MW).
Use the properties given in the file “Five Fluid Types Data.xls” under the REQUIRED
DATA folder. Your component definition form should look like Figure 7 for Dry gas
and Figure 8 in case of other fluid types. Click OK to close the Form.
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Figure 6: Definition of C7+ Variable for Black Oil Fluid Type
Figure 7: Example of Dry Gas Component Definition Screen
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Figure 8: Example of Black Oil Component Definition Screen
5.
6.
Open the Composition form and input the mole fractions of the primary composition
as mentioned in the file “Five Fluid Types Data.xls” (Figure 9). The “secondary”
corresponds to the injection fluid (if applicable). The secondary stream concept will be
covered in a later section.
(*Note: it is important that you enter a value of 0 for any components that are not
present otherwise an empty space will cause the simulator to error.)
Figure 9: Example of Black Oil Composition Form with compositions copy/pasted
from excel file
Insert a Two-phase Flash form
into the WinProp interface. Make sure that in doing
this you have first selected the Composition form.
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It is important when adding new calculations to always click on the form you want to
insert the calculation after/into. If any calculations need to be moved in a different
order they must be copied/pasted by right clicking on the item and selecting “copy/paste
after” respectively.
Open the newly inserted form by clicking on it and under the comments section type
“Standard condition flash”. We will be performing a flash at 14.7 Psia and 60 deg F.
Leave other calculation options as default. The feed composition is subjected to mixed
(i.e. primary and secondary composition). The Two-phase Flash form should look like
as shown in Figure 10.
Figure 10: Example of Two-Phase Flash Calculation Form
7.
Insert a Saturation Pressure form
into the WinProp Interface to perform a
saturation pressure calculation at the reservoir temperature.
8.
Open the Saturation Pressure Calculation form. Under the comments type “Psat at
reservoir temperature”. Also, input the reservoir temperature and saturation pressure
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estimate as 180 ºF and 1000 Psia respectively (for Dry Gas). In the other cases insert
the temperature as given in the Excel file but still use 1000 Psia.
The input value of “Saturation Pressure Estimate” is used as an initial guess by WinProp
during the iteration processes for calculating the actual saturation pressure.
Figure 11: Example of Two-Phase Saturation Pressure Form for Dry Gas
9.
We would also like to generate a pressure-temperature phase diagram. Insert a Twophase Envelope
form. Open the form and type in “P-T envelope” under the
comments section. Input the data as shown in Figure 12.
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Figure 12: Example of Two-Phase Envelope Construction for Dry Gas
10. Create plots of phase properties vs. pressure at the reservoir temperature using the
2-phase flash calculation.
Examples of properties which may be plotted are: Z-factors, phase fractions, densities,
molecular weights, K-values, etc.
This can be done by adding another Two-phase Flash calculation form. Type in the
comments “Phase properties as a function of Pressure”. Input the reservoir
temperature as 180 deg F (for Dry Gas), temperature step as 0 and No. of
temperature steps as 1. Input the reservoir pressure as 250 Psia, pressure step of
250 Psia and No. of pressure steps as 12 for dry and wet gas cases, and 24 for gas
condensate, volatile oil and black oil. The reservoir temperature will also change
depending on the case you are modeling, as mentioned in the file “Five Fluid Types
Data.xls”.
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Figure 13: Example of Two-Phase Flash Calculation used in setting up Plots for Dry
Gas. Other cases will have differing temperatures
11. In the plot control tab of the two-phase calculation form select the properties
depending on the case as follows:
No.
1
2
3
Case
Dry Gas
Wet gas
Gas Condensate, Volatile Oil & Black oil
Plot Property
Z compressibility factor
Z compressibility factor
Phase volume fraction,
Z factor, K-values (y/x)
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12. For all the oil cases, add a single-stage separator calculation with separator pressure
of 100 psia and separator temperature of 75 F. In order to do this add the Separator
Calculation
Insert Sep.
. Click anywhere inside the table to allow you to click the button labeled
Under Sat. Pres. make sure Pres. is 2000 psia and the Temp. is the same as in the file
“Five Fluid Types Data.xls”, for the specific fluid type, and click OK (Figure 14).
(*Note this is to be done only for oil cases)
Figure 14: Example of Separator Form for Black Oil
13. The final WinProp interface should look like Figure 15 for the Gaseous Cases. The oil
cases will have a Separator Calculation added after the last Two-Phase Flash
Calculation.
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Figure 15: WinProp interface for modeling Dry Gas case
14. Save the WinProp file as ‘drygas.dat’ and Run it.
15. Repeat Steps 1 to 14 and build a dat file for other types of fluid and save them as
‘wetgas.dat’, ‘gascondensate.dat’, ‘volatileoil.dat’, and ‘blackoil.dat’ files respectively
and then run.
After running these jobs analyze the Simulation Results for the different cases. These are
demonstrated in Figure 16 to 24.
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Figure 16: 2-Phase P-T diagram for Dry Gas case
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Figure 17: Vapor Z factor for Dry gas case
Figure 18: 2-Phase P-T diagram for Wet Gas case
Figure 19: Vapor Z factor for wet gas case
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Figure 20: 2-Phase P-T diagram for Gas condensate case
Figure 21: Phase volume fractions and Z factors for gas condensate
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Figure 22: K value for gas condensate case
Figure 23: 2-Phase P-T diagram for Volatile oil case
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Figure 24: 2-Phase P-T diagram for Black oil case
Additional Exercises
For the black oil data case, investigate the effect on the simulated separator calculation induced
by changing the following parameters:
• Apply the volume shift correlations
• Set the hydrocarbon binary interaction parameters to zero
• Reduce the C7+ Pc by 20%
1. To set volume shift to correlations, open Component Selection/Properties and click on
Calculate Volume Shift button then save as 'blackoil1_volshift correlation value.dat' file
(Figure 25). Go back to the Volume Shift tab again and click on Zero Volume Shift and
save as 'blackoil1_volshift set to zero.dat' file.
Run both data files and compare the results of the Separator calculations. These can be
found at the bottom of the output file which can be opened in a text editor.
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Figure 25: Calculate volume shift values
The Separator Calculations should look like to the following outputs:
Separator output with Volshift set to zero:
Oil FVF = vol of saturated oil at 2861.95 psia and 170.0 deg F per vol of stock tank oil
at STC(4) = 1.111
API gravity of stock tank oil at STC(4) = 58.10
Separator output with Volshift set to correlation value:
Oil FVF = vol of saturated oil at 2861.95 psia and 170.0 deg F per vol of stock tank oil
at STC(4) = 1.137
API gravity of stock tank oil at STC(4) = 32.77
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2. Open ‘blackoil.dat’ again and set hydrocarbon binary interaction parameter to zero. Do
this by clicking on Component Selection/Properties, click on the Int. Coef. tab (Figure
26) and click on “HC-HC Groups / Apply value to multiple non HC-HC pairs…”.
Check on HC-HC and change Exponent value to zero (Figure 27), and press OK. Save as
'blackoil1_int_coeff_zero.dat' and Run the model. Observe the result from the Separator
calculation in the output file. It should appear as follows:
Oil FVF = vol of saturated oil at 2014.47 psia and 170.0 deg F per vol of stock tank oil
at STC(4)= 1.115
API gravity of stock tank oil at STC(4) = 58.16
Figure 26: Int. Coef. Tab under Component Selection
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Figure 27: Step 17, Setting HC-HC Exponent to Zero
3. Change the Critical Pressure of the heaviest component to see its effects.
To reduce the C7+ Pc by 20%, in Component Selection/Properties change the Pc
value of C7+ to 12.36 click Apply Change (Figure 28). Save as
'blackoil1_int_coeff_reduce_Pc.dat' and Run it.
Observe the result from the Separator calculation in the output file. It should appear as
follows:
Oil FVF = vol of saturated oil at 1589.51 psia and 170.0 deg F per vol of stock tank oil
at STC(4) = 1.103
API gravity of stock tank oil at STC(4) = 104.81
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Figure 28: Changing the C7+ Component's Pc to 12.36 atm
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Exercise 2 – Determination of MMP and MME
The purpose of this exercise is to utilize WinProp to determine the Minimum Miscibility
Pressure (MMP) and Minimum Miscibility Enrichment (MME) for a rich gas injection into a
reservoir. This is generally related to enhanced oil recovery techniques such as CO2 flooding
where a gas is injected at a pressure sufficient to become miscible with the native hydrocarbon.
This can lead to a decrease in viscosity and interfacial tension which can increase mobility.
Addition of Injection Streams and Calculations
1. Open the black oil data set from Exercise 1 ‘blackoil.dat’ and Delete all of the
calculations EXCEPT the Title/EOS/Units, Component Selection/Properties,
Composition, and Saturation Pressure (Figure 29).
Figure 29: Exercise 2 Starting Parameters from Exercise 1 Black Oil Data
A variety of secondary injection streams will be added in order to determine their interactions
with the native hydrocarbons. These will include the following compositions:
• Pure N2
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•
•
•
Pure CO2
Dry gas (from Exercise 1)
A rich gas stream with the composition (in mole %):
CO2
1.4
N2
1.0
C1
33.2
C2
23.3
C3
25.3
IC4
NC4
IC5
NC5
3.8
9.6
2.1
0.3
2. To do this, begin by opening the existing Composition Form. Under the second column
labeled “Secondary” enter 100.00 into the box relating to N2. Rename the form to be
"Black Oil + N2" then hit OK (Figure 30).
Figure 30: Addition of N2 Secondary Stream to Composition
3. Next add a 2-Phase Envelope calculation and Name it "N2 Injection”. Copy and Paste
the new Component and 2-Phase Envelope Forms in the Menu so that you have two
sets of them.
4. In the second set change the Secondary stream to 100.00 for CO2 and 0.00 for N2.
Rename the Component form and 2-Phase form.
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5. Repeat the Copy/Paste and set the forms up for Dry Gas (which you get the properties of
from the “Five Fluid Types Data.xls” excel file) and Rich Gas.
The required forms and their arrangement of the calculation options in WinProp interface should
look as shown in Figure 31 for this Exercise. Save this file as
‘blackoil_richgas_MMP_MME.dat’.
Figure 31: Addition of solvents in black oil
6.
7. Implement a multi-contact miscibility (MCM) calculation to determine the MMP for pure
rich gas injection. Insert a Multiple Contacts calculation form by clicking on the
Calculations drop down menu and going down to Multiple Contacts. Input the data
shown in Figures 32 and 33.
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Figure 32: Input data for calculation of MMP
Figure 33: Rich gas (make-up gas) composition for calculation of MMP
Analyze the output file for results of single contact miscibility and multi-contact miscibility
pressures and mole fraction of make-up gas:
SUMMARY OF MULTIPLE CONTACT MISCIBILITY in *.OUT file
CALCULATIONS AT TEMPERATURE = 170.000 deg F
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______________________________________________
FIRST CONTACT MISCIBILITY ACHIEVED
AT PRESSURE 0.48250E+04 psia
MAKE UP GAS MOLE FRACTION = 0.10000E+01
MULTIPLE CONTACT MISCIBILITY ACHIEVED
AT PRESSURE = 0.37250E+04 psia
MAKE UP GAS MOLE FRACTION = 0.10000E+01
BY BACKWARD CONTACTS - CONDENSING GAS DRIVE
Multi-Contact Miscibility Minimum Pressure Calculation
Run a multi-contact miscibility calculation to determine the minimum amount of rich gas
necessary to add to the dry gas to achieve miscibility at 4500 psi (MME calculation).
1. Insert a new Multiple Contacts form and input the following parameters.
Notice that in this case only one pressure value is used at which the miscibility is
desired. In the composition form the starting point for the make-up gas fraction is
from 50%.
Figure 34: Input data for calculation of MME calculation
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Figure 35: Rich gas (make-up gas) composition for calculation of MME
Analyze the output file for results of single contact miscibility and multi-contact miscibility
pressures and mole fraction of make-up gas:
SUMMARY OF RICH GAS MME CALCULATIONS AT TEMPERATURE = 170.000 deg F
FIRST CONTACT MISCIBILITY PRESSURE
(FCM) IS GREATER THAN 0.45000E+04 psia
MULTIPLE CONTACT MISCIBILITY ACHIEVED
AT PRESSURE = 0.45000E+04 psia
MAKE UP GAS MOLE FRACTION = 0.90000E+00 psia
BY BACKWARD CONTACTS - CONDENSING GAS DRIVE
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Exercise 3 – Creation of Raleigh Black Oil
The purpose of this exercise is to utilize WinProp in building a Black Oil fluid model. This
exercise will introduce the concept of Plus Fraction Splitting of components and the tuning of
component values and Equation of State to match laboratory experiments such as Constant
Composition Expansion (CCE), Separator Tests, and Differential Liberation (DL). This will be
done on a new WinProp model.
Setup of WinProp model with Plus Fraction Splitting
1. Initialize WinProp through CMG launcher.
2. In the Titles/EOS/Units form insert a title: “Plus fraction characterization” and select
PR (1978), Psia & deg F, and feed as moles.
3. In the Component Selection/Properties form add the following library components:
CO2, N2, and C1-C6 (DON'T ADD C7+)
Under the Composition form add the compositions as given in the file:
“Raleigh black oil-data1.xls”.
Figure 36: Black oil composition for Raleigh oil
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4. To add and split the C7+ fraction into pseudo-components select Composition then click
Characterization|Plus Fraction Splitting.
On the General Tab specify Gamma distribution function, the first single carbon
number in plus fraction as 7, 4 Pseudocomponents, Lumping Method as Gaussian
Quadrature, and leave the other properties as default.
Figure 37: Plus fraction splitting for Raleigh Oil General Tab
5. Go to Sample 1 Tab and input the MW+ as 190, SG+ as 0.8150, and Z+ (mole fraction
of C7+ fraction) as 0.2891. Make sure alpha is equal to 1.
Figure 38: Plus fraction splitting for Raleigh Oil Sample 1 Tab
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6. Save the dataset as ‘raleigh oil.dat’ and Run it.
After running the data set, use the Update component properties in the File menu and
delete Plus Fraction Splitting. Save the data set as ‘raleigh oil_plus fraction
splitting.dat’. You will now notice that 4 hypothetical pseudo components have been
added in the components form.
Defining Calculations and Experimental Values
1. In order to match the CCE, Differential liberation and separator test, use the data given in
the file “Raleigh black oil-data1.xls”.
Add Saturation Pressure, Constant Composition Expansion, Separator, and
Differential Liberation forms in sequence. Input the experimental data given in the file
“Raleigh black oil-data1.xls” (Figures 39-44). (You can also input all above forms, from
another WinProp dataset by copy/pasting).
Figure 39: WinProp Forms Inserted in Step 7
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Figure 40: Saturation Pressure Form with Data from Excel File
Figure 41: Constant Composition Expansion Form with Values for Pressure and
Exp. ROV Copy/Pasted from Excel
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Figure 42: Separator Form Populated with data from Excel file
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Figure 43: Experimental Tab of Separator Form Populated with Data from Excel
file
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Figure 44: Differential Liberation Pressure Levels Tab with Excel Data (entire excel
table can be copied and pasted directly into this)
2. In the Component Selection/Properties form, click the “Calculate Volume Shift”
Button and hit Apply Change to calculate the volume shifts using correlation values.
Save your model as ‘raleigh oil_experimental data.dat’ and Run it once to validate
your model and check for errors in the input data.
Using Regression to Match WinProp model to Laboratory Results
3. Select Differential Liberation then click on Regression Start
on the top menu to
place Regression Parameters after everything else. In Regression Parameters go to the
Component Properties tab.
Select Pc and Tc for the Heaviest Component.
For all of the C7+ pseudocomponents and C1 select the volume shifts (Figure 45).
Figure 45: Component Properties for experimental data matching
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In the Interactions Coefficients tab, select the hydrocarbon interaction coefficient
exponent (Figure 46). Set the convergence tolerance to 1.0E-06 in Regression Controls
tab (Figure 47).
Figure 46: Interaction Coefficients tab setting Hydrocarbon Interaction Coefficient
Exponent
Figure 47: Regression Control tab displaying where to change the Convergence
tolerance
4. Select Differential Liberation and Delete/Cut, and then click on Regression
Parameters and Paste into Reg-Block.
Select Separator and Delete/Cut then click on Regression Parameters and Paste into
Reg-Block.
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Do this for both Constant Composition Expansion and Saturation Pressure as well.
Your window should now look like Figure 48. Run and check for errors in the output file.
Figure 48: WinProp Calculations Layout including Regression Parameters
5. Adjust the weight of some key experimental data points. Try setting the weight for the
API gravity to 5.0 in the Separator -> Experimental Data tab; 10.0 in the Saturation
Pressure form; and in the Differential Liberation form set the API gravity at STD
conditions to 0.0. Re-run the regression.
6. In some cases, you may have to change the lower and upper bounds of the regression
parameters depending on whether these bounds are reached during the regression. In this
case the following bounds were used:
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Figure 49: Variable bounds used during the regression
Analyze the *.out file and refer to the Summary of Regression Results for comparison
of the experimental versus calculated values.
7. After completing the match to the PVT data, Update component properties and Save
the file under a new name as ‘raleigh oil_experimental data_vis.dat’ in preparation for
viscosity matching.
Matching Viscosity in WinProp to Laboratory Values
1. For viscosity matching, temporarily exclude the Saturation Pressure, Constant
Composition Expansion and Separator calculations from the data set by right-clicking on
each option and select Exclude from the pop-up menu (Figure 50).
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Figure 50: WinProp Calculations with Exclusions as per Step 15
2. In Differential Liberation set the weight for the viscosity data to 1.0, and all other
weights to 0.0 (Figure 51).
Figure 51: Differential Liberation with Weighting Factors of everything except
Viscosity set to 0
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3. In Regression Parameters remove all previously selected parameters from the
Component Properties and Interaction Coefficients tab.
On the Viscosity Parameters tab select C1 and the C7+ pseudo components as
regression variables (Figure 52). Run the data set. Check for errors in the output file.
Figure 52: Viscosity Regression Parameters for C1 and C7+ Pseudo-Components
4. After completing the match to the viscosity data, Update component properties and
Save the file under a new name ‘raleigh oil_Blackoil PVT.dat’ in preparation for
generating the IMEX PVT table.
Defining an IMEX Fluid Model Output
1. Select Regression Parameters and Delete/Cut. The Saturation Pressure, Constant
Composition Expansion and Separator options should still be on the side bar, right-click
on each and choose Include from the pop-up menu. Now select the bottommost
calculation form and Add After -> Simulator PVT -> Black Oil PVT Data (Figure 53).
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Figure 53: WinProp Calculations Layout for Step 19
2. In Black Oil PVT Data, enter the saturation pressure data, desired pressure levels
and the separator data (Figure 54). Enter mole fractions of 0.1, 0.2, and 0.3 for the
swelling data (Figure 55).
Figure 54: Black oil PVT export for IMEX Saturation Pressure Tab Inputs
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Figure 55: Pressure levels for back oil PVT
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Figure 56: Water properties for back oil PVT
3. Leave the Oil Properties controls at the defaults, and then select “Use solution gas
composition…” for the swelling fluid specification on the Gas Properties tab. Run the
data set and check the output file.
If you see the following messages in the output file:
Then do the following:
• Open the *.dat file in Textpad
• Search for the keyword JSAT-SWEL
• Make sure that the numbers on the line directly below are only integers (it should be 2
instead of 2.0)
• Save the file and run the data set again. The messages should be cleared.
•
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Exercise 4 – Heavy Oil Fluid Model
The purpose of this exercise is to utilize WinProp in building a Heavy Oil Model. Commonly,
such models will be used in STARS for thermal applications. Because of this thermal properties
may play a larger role than observed in Black-Oil fluid models (such as Exercise 3). This fluid
model will be created by incorporating similar techniques implemented in Exercise 3, including
matching laboratory data, as well as some new concepts, such as Plus Fraction Splitting.
Setup of WinProp model with Plus Fraction Splitting
1. Open WinProp through CMG launcher.
2. In the Titles/EOS/Units form insert a title: “Fluid Model for STARS” and select PR
(1978), kPa & deg C, and feed as moles.
3. In the Component Selection/Properties add the library component C1. Open the
Composition form and add the composition for C1 as given in the file “Heavy Oil for
STARS-Data1.xls”. (The mole fraction of C1 is 0.08223).
4. The laboratory has supplied a C6+ component which now needs to be split into
pseudocomponents.
In order to split the C6+ fractions, insert a Plus fraction Splitting form in the WinProp
interface after the Composition form. The first single carbon number in plus fraction
should be 6. Specify the number of Pseudo-components to 4 and select Gamma,
Gaussian Quadrature, and Lee-Kesler (Figure 57).
Figure 57: Plus Fraction Splitting for Heavy Oil
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5. In the Sample 1 tab, input SG+ as 0.989 and the global mole fractions and molecular
weights for liquid component as given in the file “Heavy Oil for STARS-Data.xls”
(Figure 58).
Figure 58: Plus fraction splitting for Heavy Oil
6. Add a Saturation Pressure form (Figure 59). Save the dataset as ‘S1-char.dat’ and Run
it. After running the data set, Update component properties and Save the data set as
‘S2-regression psat.dat’.
You will now notice that 4 hypothetical pseudo components have been added in the
components form.
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Figure 59: Saturation Pressure Calculation added per Step 6
Matching of WinProp Model to Laboratory Results
Due to splitting the component into 4 pseudocomponents a regression/tuning must be
performed to match the WinProp model to the experimental data.
1. The first experimental value to match is the Saturation Pressure. Delete Plus Faction
Splitting, and then add Regression Parameters below Composition.
Then select Saturation Pressure and Delete/Cut and click Regression Parameters and
Paste into Reg-Block.
On the Regression Parameters form, select Pc and Tc for the heaviest
pseudocomponent. In the Interactions Coefficients tab select the hydrocarbon
interaction coefficient exponent.
Run the dataset. After running the dataset, Update component properties and Save the
data set as ‘S3-lumping.dat’.
2. Delete Regression Parameters, than add a Component Lumping form and lump the
last three heavy components by highlighting all three then selecting the bottom-most
component. The Component Lumping form should look like Figure 60.
3.
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Figure 60: Component Lumping form for Heavy Oil
4. Run the dataset. After running the dataset, Update component properties and Save the
data set as ‘S4-regression.dat’.
5. Delete Component Lumping and add Regression Parameters. Then select Saturation
Pressure and Delete/Cut and click Regression Parameters and Paste into Reg-Block.
Select Regression Parameters and Add into Reg-Block -> Lab -> Separator. Enter
saturation pressure, reservoir temperature, GOR and API data from “Heavy Oil for
STARS-Data1.xls” (Figures 61-63).
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Figure 61: Saturation Pressure Form Populated with Excel Values
Figure 62: Separator Form Populated with values from Excel File
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Figure 63: Separator Form Experimental Tab Populated with Excel Values
6. In Regression Parameters under the Component Properties tab select Pc and Tc for
the Heaviest component, and Vol. shift for the 2 Heaviest components. Run the
dataset. Check for match in regression summary. After running the dataset, Update
component properties and Save the data set as ‘S5-regression_visc.dat’.
7.
Figure 64: Regression Parameters Set per Step 11
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Matching of WinProp Model Viscosity to Laboratory Viscosity
We will repeat the regression to match Viscosity at 10 deg C (Figures 65 and 66) and 100
deg C (Figures 67 and 68) as given in “Heavy Oil for STARS-Data.xls”.
1. Insert 2 Two Phase Flash forms to input experimental viscosity data (Figures 65 and 66)
Figure 65: Two-Phase Flash Calculations for viscosity data of Heavy Oil (10 deg)
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Figure 66: Two-Phase Flash Experimental Data viscosity of Heavy Oil (10 deg)
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Figure 67: Two-Phase Flash Calculations viscosity data of Heavy Oil (100 deg)
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Figure 68: Two-Phase Flash Experimental Data viscosity of Heavy Oil (100 deg)
2. In Component Selection/Properties on the Viscosity tab, set viscosity model type to
Pedersen Corresponding State Model and the corresponding states model to
Modified Pedersen (1987), (Figure 69).
In Regression Parameters, Viscosity Parameters tab, select all check boxes. Run the
dataset. After running the dataset, check for a match.
You may have to change variable bounds to improve the match.
When an acceptable match has been found Update component properties and Save the
data set as ‘S6-STARS PVT.dat’.
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Figure 69: Viscosity Component Definition Tab showing changes to Modified
Pedersen
Creating a STARS PVT Model from WinProp
1. Delete Regression Parameters then insert 2 CMG STARS PVT Data forms from the
Simulator PVT drop down menu.
2. On the first CMG STARS PVT Data form, on the Calc. Type tab select “Basic STARS
PVT Data”. Then on the Basic PVT tab enter the initial reservoir conditions (3200
kPa and 12 C) as the reference conditions.
Generate a Component liquid viscosity table from 10 C to 360 C with 8 steps and use
the WinProp viscosity model (Figure 70). Set lower pressure at 500 kPa, upper
pressure at 5500 kPa and number of steps as 10.
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Figure 70: STARS PVT Data Generator with Initial Reservoir Conditions
3. On the second CMG STARS PVT Data form, on the Calc. Type tab select “GasLiquid K-value Tables.” On the K-Value tab enter 500 kPa for both the Pressure and
Pressure Step and 9 for the No. of pressure steps. Also enter 10 C for Temperature, 50
C for Temperature Step, and 8 for No. of temperature steps.
Entering a minimum K-value threshold of 1.0E-06 will improve STARS numerical
stability without materially affecting the simulation results (Figure 71). This option sets
any K-Value less than this threshold to 0.
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Figure 71: STARS PVT Data Generator K-Value Data Entries
4. Save the dataset under a new name and Run it. The information obtained is now capable
of being imported to a STARS dataset and Ran.
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