X2t reaction

[Frederick Gyaase]

I am trying to get this reaction together but there a lot of parameters that I don't have. 

1. I want to know if these parameters can be found in a particular data base on Geochemist's Workbench or

2. They are in built.

The parameters i need are in the screenshot attached below. I am using Fond Du Lac rock.

In the third picture, I have indicated a section in a red ink, what is the best value to put there?

how do i get the values in the last picture?

[Jia Wang]

Hello,

You can review the GWB Reactive Transport Modeling User Guide for how to set up a simulation in X1t and X2t. You would need to provide information (e.g. kinetic rate constants) to create a simulation on your own. Though, if the software is new to you, I would recommend that you start with the single-node applications (SpecE8 or React) and familiarize yourself with how to configure chemical systems before jumping into a reactive transport model. There are a plethora of resources to help you get started. I would recommend starting with the GWB Essentials User Guide, in section 2 Configuring the Programs.

Information on setting up various types of reactants can be found in the GWB Reaction Modeling Guide. I would recommend starting in section 2 Getting Started with React when you are ready.

You can find the guides under the "Help" menu of any GWB applications or by going to the Docs pane on your GWB dashboard. All examples in the guides can be found in the Scripts folder, where the GWB is installed.

There are also a variety of fully worked examples available on the GWB Academy.

Hope this helps,
Jia Wang
Aqueous Solutions LLC

[Frederick Gyaase]

Hi Wang

Thank you for your support

[Frederick Gyaase]

I tried inputting my values and after running, this is the outcome I got. I don't know what could be wrong.

Kindly help me. Thank you.

[Brian Farrell]

Hi Frederick,

It looks like there is probably some problem with the initial system you defined. If you attach your .x2t file we can try to see what the issue might be.

Regards,

Brian Farrell
Aqueous Solutions

[Frederick Gyaase]

Hi Brian,

Please find attached the .x2t file.

 

Thank you. 

x2t_resume.x2t

[Brian Farrell]

Hi Frederick,

Your nodal blocks are quite small, which would be fine except that you've constrained the Na+ and Cl- components in terms of in absolute units (mass in g) instead of relative units (e.g. concentration in g/kg solution). So, that is equivalent to setting up extremely high Na+ and Cl- concentrations. You've set up the rest of the fluid in terms of relative units (concentrations of HCO3-, Ca++, and Mg++ are all in mmol/kg), so I think you'll want to use "/kg" units for the Na+ and Cl- as well.

Cheers,

Brian 

[Frederick Gyaase]

Thank you, Brian.

[Frederick Gyaase]

Dear Brian and Wang, 

Attached is the plot of the results I got, but the problem is, it's difficult for me to explain this or make any meaning out of it when I compare it to my experimental work. Could you please elaborate this plot for me? I injected NaCl solution into a Fond Du Lac rock sample, I wanted to see what comes out of the production. 

 

Thank you.

[Jia Wang]

Hello Frederick,

Xtplot can render the results from your reactive transport model and display them in different ways. In your screenshot, there is a color map that shows temperature and a set of contour lines for pH. You can see this information on the side banner on the left side of the plot. To learn more about how to configure Xtplot to show the variables that you want to display, please familiarize yourself with section 6 of the GWB Reactive Transport Modeling User Guide.

Hope this helps,
Jia

[Frederick Gyaase]

Thank you Wang.

[Frederick Gyaase]

Hi Jia and Brian,

From the Wells section in the X2t app, how do I add a production well? I had like know what comes out of my production well. 

[Jia Wang]

Hello Frederick,

You are on the right pane to set up an injection or extraction well. For an extraction well, you would set a negative rate, which would indicate to the program that you are extracting fluid. You do not need to set a fluid composition in that case. You can plot the results of an individual node in a reaction transport model in Xtplot using the XY plot configuration. You would want to set the X axis to time and then the variable of interest on the Y axis pane. On the Position pane, you can check "Wells first" and then select your well.

You can see sections 4.2 Wells for a more detailed explanation and 4.9 Example: metals contamination of an aquifer in the GWB Reactive Transport Modeling User Guide for a worked out example. Specific information regarding XY Plot configuration in Xtplot can be found in section 6.2 in the same user guide.

Hope this helps,
Jia

[Frederick Gyaase]

Hello Jia,

 

Thank you for your assistance.

[Frederick Gyaase]

Hello Jia,

 

I did a dual injection: 10% of H2 gas and 90% of Nacl solution of total flow rate 0.05cc/min in the same rock sample. I am trying to simulate this. Is there any way I can input this on the X2t software?

Again, is there any way I can also add pressure as I could do to temperature?

[Jia Wang]

Hello Frederick,

The software accounts for the effect of gas on an aqueous system by gas partial pressure or fugacity. For example, you can set a gas partial pressure in equilibrium with your injection fluid, then have the software calculate the corresponding dissolved concentration of the gas. I would recommend that you work in the React application to get the chemistry of your injection fluid correct before setting it in the reactive transport model applications.  Please see section 7.2 Equilibrium models in the GWB Essentials User Guide for an example on how to set partial pressure in equilibrium with your initial system.

Please note that the GWB does not keep track of the mass of gas in the reservoir. Additionally, please note that the reactive transport programs consider the flow of the aqueous phase only; they are not multiphase simulators.

You can't set confining pressure within GWB apps except in Act2 and Tact. All thermodynamic data in the datasets distributed with the GWB is compiled along the steam saturation curve. So you'll see a pressure of 1.013 bars up to 100 C, then the vapor pressure of water above that temperature. You can take a look at the Tables section (open in TEdit) of the thermo datasets to see the pressures corresponding to the principal temperatures.

If you wish, you can compile a thermo dataset at a specific pressure or temperature of interest. For more information, please refer to the K2GWB and DBCreate references on our thermo data page. However, unlike temperature, you cannot set pressure independently.

Hope this helps,
Jia

[Frederick Gyaase]

Thank you Jia.

 

I have another question; is there any way I can convert this plot into excel in other to get the data in a tabular form?

[Jia Wang]

Hello,

You're welcome. You can certainly copy plot data to a spreadsheet. You can do this by going to Edit -> Copy as -> select Spreadsheet and then pasting in your spreadsheet program. Please see section 6.7 Exporting the plot in the GWB Reactive Transport Modeling User Guide for more details.

Hope this helps,
Jia

[Frederick Gyaase]

Hello Jia,

Please I would like to know if there is any dataset available which contains olivine? or do you have any suggestions that I can import olivine dataset from any source?

 

Thank you.

Fred.

[Brian Farrell]

Hi Fred,

The default thermo dataset, thermo.tdat, contains several olivine-group minerals. If you’re only interested in a particular end member, you could use one of those. Or, you can define a binary solid solution. For more information, please see section 2.5, Solid solutions, in the GWB Essentials Guide.

Hope this helps,

Brian Farrell
Aqueous Solutions

[Frederick Gyaase]

Thank you, Brian.

I am trying to add catalyst like CO2, NaHCO3, Nikel, and Co in my system (file attached). How do I introduce these catalysts in the software?

Olivine rxn.rea

[Brian Farrell]

It's hard to tell exactly what you need, so I recommend reading chapters 2, 3, and 4 in the GWB Reaction Modeling Guide to get started.

[Frederick Gyaase]

Hi Brian, I am trying to produce hydrogen but by adding a catalyst, the hydrogen production is higher. Now the problem is that I don't know where to add the catalysts mentioned above, whether in the initial fluids or in the reactant pane.