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  2. Brian Farrell

    Script in Chemplugin

    Hi Johan, The inner quotes in the kinetic rate law need to be escaped with a backslash (e.g. \"H+\" or \'H+\') . For the thermo data, the issue is the same. You can do something like this: cmds = ('data = "C:\\Program Files\\ChemPlugin\\Gtdata\\thermo.com.V8.R6+_MRM_JF.tdat" ', Hope this helps. We appreciate your patience. Regards, Brian
  3. JohanFourie

    Chemplugin: Pore Volume (PV) and Extendrun()

    "Hi Brian This works well for my model when changing the flowrate. But now I want to change a configuration of one of the instances also at a certain timestep. 1) Can I still do it before the time marching loop (this doesn't seem to work) or should I use extend run if I want to change the configuration 2) Have I done it correctly below or should I use the "remove" and "add" functions? Both temp and Br are already in the configuration - I just want to change their values..... 3) Can one also use the "slide" function in chemplugin? I also tried it but chemplugin ignored it. for n in range(0, var_ScenFlow): ………………………..for each flow scenario: if n == 1: ……………………….not at the 0 flow scenario but for the 1 one var_Temp2 = var_Temp1 cp_reactor[2].Config("Temperature = " + str(var_Temp2) + " C") ……………………...change the temperature in the configuration cp_reactor[2].Config("Br- = 1 mg/l") ……………………….change the tracer concentration # Time marching loop. while True: for c in cp_reactor: deltat = c.ReportTimeStep() …………….etc
  4. Hi Jeonghwan Hwang, There are various thermodynamic datasets installed with the software. You can search through them for minerals that you need. In a text editor, you might try to search (ctrl+F) on smectite or clay to find minerals of that type that would be representative of a montmorillonite group mineral. Or in TEdit, the GWB’s graphical thermo data editor, you can use the filter option to show only minerals with Al+++, SiO2(aq), etc to find the clays. If you don’t see the mineral you need in any of the datasets, you can add a new mineral using information from the literature. You need to supply its reaction and log K at one or more temperatures, as well as its mole weight and mole volume. For more information, please see the Thermo Datasets chapter in the GWB Reference Manual and the Using TEdit chapter in the GWB Essentials Guide. Regards, Brian Farrell Aqueous Solutions LLC
  5. Jeonghwan Hwang

    Smectite dissolution with Sulfuric Acid

    Dear, pavanpec30 Hello, this it Jeonghwan Hwang, i'm new to GWB. I'm interested in Montmorillonite-illite diagenesis and want to make a phase diagram. Unfortunately, i cannot find any similar mineral as montmorillonite in GWB. Can you help me to find the montmorillonite? Thank you Sincerely, Jeonghwan Hwang
  6. Brian Farrell

    Script in Chemplugin

    Hi Johan, Thanks for the additional information. I'm looking into this issue. Regards, Brian
  7. Brian Farrell

    Jude

    Hi Jude, Please don’t post multiple topics about the same issue. I’ve responded to your query in the original post. We appreciate your patience and hope you enjoy using the free GWB Student Edition. Regards, Brian
  8. Brian Farrell

    Eh vs Ph

    Hi Jude, Ok, you showed an Eh vs. log a HCO3- diagram before (Figure 1D/2D). Now you want to make an Eh-pH diagram (Figure 1A/2A) instead? If so, based on the caption to Figure 1A, you need to set the HS- activity to 10^-12 and add HCO3- with an activity of 10^-2. For each different diagram you want to make, you need to pay close attention to the conditions indicated in the figure caption. After getting the geochemical constraints right, the most important step is to make sure the thermodynamic data you’re using in Act2 matches that used in the original reference. There are potentially multiple different sources of data in thermo.comV8.R6+.tdat. It’s also possible the information in SUPCRT has changed over the years. I think you’ll need to calculate the log K for every relevant reaction from the delta G o formation values listed in Table 2 and see if they match the log K values in the GWB thermo dataset. If not, you can permanently modify the log Ks in the thermo dataset, or you can temporarily change them within an Act2 run using the “Alter log K” feature. Finally, it looks like the publication used a relatively short list of species in its calculation. Act2, on the other hand, will load every possible species that can be formed based on the specific basis – in your case Fe++, H2O, e-, H+, HCO3-, and HS-. You may need to suppress certain species, like FeHCO3+ or FeCO3(aq), if they appear in Act2 but not in the original calculation. For more information, please see the “alter” and “suppress” commands in the Act2 chapter of the GWB Command Reference. Please see as well the Using Act2 and Using TEdit chapters in the GWB Essentials Guide. Regards, Brian
  9. jude osamor

    Jude

    Hi Bryan, I've tried to decoupled i'm still not getting the same thing. Please I will appreciate your input. Regards, Jude
  10. Hi, this is Jeonghwan Hwang. I wan't to make the phase diagram for montmorillonite-illite diagenesis using temperature and pressure. But i cannot find the montmorillonite in any mineral information. How to find the montmorillonite? I am very pleased to help me. Sincerely, Jeonghwan Hwang
  11. jude osamor

    Eh vs Ph

    Hello Brian, Please help me have a look at my reply. Thanks Jude
  12. Earlier
  13. JohanFourie

    Script in Chemplugin

    Hi Brian I tried different ways with the quotation marks. If I use single quotes, then there is no error, however chemplugin just ignores the line. I may have a similar problem when I want to assign a different database when using python. There is no error but chemplugin just ignores this and use the default database anyway, e.g. cmds = ('data = "C:\Program Files\ChemPlugin\Gtdata\thermo.com.V8.R6+_MRM_JF.tdat" ', …...etc I have tried to use all different ways with the quotation marks but it doesn't help. Regards Johan
  14. jude osamor

    How to remove the dashed line in the mosaic diagram of Act2

    Hello Polly, Please do you know to plot Eh vs Ph plot on act2 with your own database put in the system
  15. jude osamor

    Eh vs Ph

    Hello Brian, Thank you for your prompt response. I've tried to decouple it as you advised, it's not giving me the same thing as the model. The data base i used is the thermo.com.V8.R6+.tdat which is said to be gotten from SUPCRT92 . I've also attached my input file as well. To be honest, i saw model i'm working on in a paper which i attached below there are no other information on how the Model was built. I look forward to your favourable assitance with this Brian. Regards Jude Hello Brian, Thank you for your prompt response. I've tried to decouple it as you advised, it's not giving me the same thing as the model. The data base i used is the thermo.com.V8.R6+.tdat which is said to be gotten from SUPCRT92 . I've also attached my input file as well. To be honest, i saw model i'm working on in a paper which i attached below there are no other information on how the Model was built. I look forward to your favourable assitance with this Brian. Regards Jude MAG-4_Burton.Machel.Qi_SEMP_1993.pdf
  16. Brian Farrell

    Eh vs Ph

    Hi Jude, It's really hard to tell without any knowledge of how your model or the originals were set up. One guess is that the originals considered only inorganic carbon, whereas you're forming various organic species under reducing conditions. You can decouple the various carbon redox species from the HCO3- basis species to limit your calculation to inorganic carbon. For more information, please see 2.4 Redox couples and 7.3 Redox disequilibrium in the GWB Essentials Guide. If you have more questions, you'll have to provide your Act2 input file, your thermo dataset, and more information about how the original diagrams were made. Regards, Brian Farrell Aqueous Solutions
  17. Brian Farrell

    Script in Chemplugin

    Hi Johan, Can you try using single quotes for the helper functions? For example, activity('H+'). Hope this helps, Brian Farrell Aqueous Solutions
  18. JohanFourie

    Script in Chemplugin

    Hi Brian We struggle to write a script in Chemplugin for the reaction rate of kinetic minerals. The script for dolomite is given below. Python also don't like the double notation: "H+" for the parameters. "kinetic Dolomite-Mn 12.1 volume% rate_law = script 'rate = (1.49e-02*EXP(-29000/(8.3144598*TK))*activity("H+")^0.75 + 1.00e-02*EXP(-34800/(8.3144598*TK))*activity("H2CO3")^0.75 + 2.20e-7*EXP(-52200/(8.3144598*TK))*activity("H2O")^0.75) * surface * (1 - QoverK) RETURN rate' pre-exp = ??? act_eng = ??? surface = .65" We would appreciate your help. Regards Johan
  19. JohanFourie

    Script in Chemplugin

    Hi Brian We struggle to write a script in Chemplugin for the reaction rate of kinetic minerals. The script for dolomite is given below. Python also don't like the double notation: "H+" for the parameters. "kinetic Dolomite-Mn 12.1 volume% rate_law = script 'rate = (1.49e-02*EXP(-29000/(8.3144598*TK))*activity("H+")^0.75 + 1.00e-02*EXP(-34800/(8.3144598*TK))*activity("H2CO3")^0.75 + 2.20e-7*EXP(-52200/(8.3144598*TK))*activity("H2O")^0.75) * surface * (1 - QoverK) RETURN rate' pre-exp = ??? act_eng = ??? surface = .65" We would appreciate your help. Regards Johan
  20. jude osamor

    Eh vs Ph

    Dear Bryan, Please i'm in need of help with Eh vs Ph plot with act2. I'm trying to reproduce a thermodynamic model that was done with SUPCRT92 with Geochemist Work Bench's thermodynamic Model. I realise that my result is not the same, even after using same Delta G values that was used in SUPCRT92. Please any ideas why the results are not the same please? is there any way you can help me. I want to reproduce the same thing that was done on SUPCRT92.
  21. Hi KH, This is an interesting problem. It’s similar to the “mosaic diagram” feature in Act2, but it’s the axis variable that needs to speciate. There’s no way to account for this in the simple calculations that Act2 performs, apart from drawing separate diagrams for the regions in which HS- or H2S predominate. An actual multicomponent chemical model, like a SpecE8 calculation, allows you to handle more complexity. For a single condition, you can calculate the predominant Sb species or stable Sb minerals. You can set the composition of a fluid in terms of total (or component) concentrations, and the program will account for the complete set of equations describing the distribution of mass. You can take this analysis a step further in React by looking at the effect of one variable at a time. By titrating HS- into a fluid at a fixed pH (preferably using log steps), or by sliding the pH in fluids of specified total HS- concentration, you can look at the effects of total HS- or pH on species predominance and mineral stability. Essentially, these calculations are like transects plotted through the 2D diagram you’re envisioning. The best solution to make the diagram you want is to use the new Phase2 program in GWB12. It was created for problems like this. It’s essentially a two-stage calculation in which a series of React paths are stacked together to form a 2D grid. Some diagrams may resemble what you can calculate in Act2, but you have many more capabilities and fewer simplifying assumptions. I've attached an example of the diagram I think you're trying to make, using Phase2 and the thermo.com.V8.R6+.tdat dataset. Hope this helps, Brian Farrell Aqueous Solutions LLC
  22. I am trying to plot Sb(III) speciation over pH as a function of sulfide, which itself speciates over pH (using Arc2). The x axis is pH and the y axis should be the sum of HS- and H2S concentrations. I have added the thermodynamc data for Sb sulfide complexes to the database, but sulfide does not speciate as HS-/H2S. I managed to plot Sb speciation with either HS- or H2S as the y axis and I have attached these files. Could you please advise me if (and how) it is possible that sulfide speciates over pH (no redox reactions required) to merge the two diagrams into one? Thanks a lot KH
  23. Hi Polly, I’m glad to hear that your uraninite solubility calculation worked out well. You might try charge balancing on a different ion, or disabling charge balancing entirely, since this is a simple solubility diagram calculation. Regards, Brian Farrell Aqueous Solutions
  24. Brian Farrell

    GSS student edition

    Hi Raquel, GSS is a spreadsheet for storing water analyses. As you've discovered, you can create "user-defined variables" to store certain properties, like your gas weight percents. GSS doesn't use these in any of its calculations, though. The only input GSS accepts for its calculations are the concentrations of the basis species (thermodynamic components in the fluid) and a few parameters like temperature, pH, and Eh. GSS can calculate gas fugacity or partial pressure from the activity of the dissolved gas species. You need to create a chemical model of the fluid to do this. For your information, GSS uses a program called SpecE8 to perform its calculations. You should familiarize yourself with SpecE8 before working with GSS. From the screenshot of your spreadsheet, it appears you've already found how to add the temperature. Click +analyte > Chemical parameters > Temperature. For pressure, click +analyte > Physical parameters > Pressure. For more information, please see the Using SpecE8 and Using GSS chapters of the GWB Essentials Guide. Regards, Brian Farrell Aqueous Solutions
  25. Hello, Yesterday I tried to enter data of weight percentage of some gases present in an oil field, so that the software could then calculate the fugacity, activity and partial pressures of these gases. When I gave the option to calculate to select what was the calculation I wanted, it indicated an error indicating that there is not an initial system specified. What should I do? can you help me? would I skip a step? Also, I would like to enter the reservoir temperature and pressure so that I can consider them in the calculation and I do not know how to do it. Attached a screen print. Regards, Raquel print error gwb gss.pptx
  26. From 1 user to another: GWB does not have the facility to include statistical distribution of parameters. Option 1: Manually run various scenarios with consideration of the statistical distribution of the most sensitive parameters. Let say the 50, 66 and 95 percentile of a parameter. Option 2: Write a code in Chemplugin that run several models for you with consideration of the statistical distribution of your parameter (which might even be a water balance component). I have not done it myself but think it is a great idea - but one would probably need a lot of time for the development of the code. If you have several parameters with several different distribution functions, I would say first try to simplify your conceptual model as much as possible...….
  27. Hi Brian, Thanks for everything!
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