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  1. Today
  2. Hi Brian, thank you for the information. Acutally I wanted to use the activity model "phreeqc" so this is one of the reasons I got in this trouble. I should more often remember to "RTFM"... ;-) Thank you and best wishes! Frank
  3. Hello, I use Spec8 to do an ion exchange simulation (please see this: https://www.e-education.psu.edu/png550/node/836), and have some questions. 1) In the simulation, they give a value of "specific surface area". Can I add this condition in Spec8? (And how to do it?) 2) There are some different results between Spec8 and the website. Is it because we do not use the same thermo data or maybe others reason? Thank you for your help. Betty TEdit_3_V.sdat test.sp8
  4. Yesterday
  5. Hi Frank, The biggest problem is that you’re missing values for Bdot and the water activity coefficient terms in the Tables section of your thermo dataset. You’ll probably also want to set real values for the ion size parameter for the basis and aqueous species, since 500 is currently being used. For more information, please see the Thermo Datasets chapter of the GWB Reference Manual. Regards, Brian Farrell Aqueous Solutions LLC
  6. Hello, I have prepared a database (attached) and both TEdit and React are loading the file without any warning. But even the simplest calculations fail and give an error message like this: Is there a way to locate the error to make it work? Thank you in advance and best regards, Frank thermo_test.tdat Test.rea
  7. Last week
  8. Friso

    pH effects in X1t and X2t

    Brian, thank you for your prompt response!
  9. Hi Brian, Thank you for this. It helps. I have now removed the reactants and tried several runs modifying the Initial (volume % of mineralogies relative to fluid, thus porosity, fluid composition, charge balance), but none of them are converging. The residual is, if I understand properly, too high for Na+. I tried the charge balance on Na and K instead of Cl. But I'm having the same issue. I manage to do the model with react though. So I am not sure what I am not doing right in x1t. I attached both the x1t and react scripts. I have changed the thermodynamic dataset so that it won't be an issue for you to open. In the initial pane, I entered a simple fluid composition and host-rock composition (basalt). Do I need to run react first to get those two at equilibrium and use the results in the initial pane of x1t? Just like I would have to do it for a flush model in react, using the "pick up" command? For the sake of simplicity here, I am assuming the mineralogy is in equilibrium with the fluid, and I am not using kinetic reactants. Any help would be much appreciated Regards Coralie Tholeiitic-basalt-simple-brine-2.x1t Simple-fluid-tholeiitic-basalt.rea
  10. Earlier
  11. Brian Farrell

    pH effects in X1t and X2t

    Hello, To simulate the continuous addition of ions into the fluid, you should use simple reactants. On the Reactants pane, click add > Simple > Aqueous… > H+. You’ll see a line that includes “React H+ + 0.0 mmol”. Click the “+” button to set a heterogeneous value for the rate of H+ addition. You might use the node-by-node editor or an equation to set the rate of H+ addition at the node containing the anode, and a rate of 0 everywhere else. The procedure is just like setting the spike in initial Pb concentration in the Diffusion tutorial. For more information, please see 3.1 Titration paths in the GWB Reaction Modeling Guide and the Heterogeneity Appendix to the GWB Reactive Transport Modeling Guide. Regards, Brian Farrell Aqueous Solutions LLC
  12. Hi Coralie, Do the minerals swapped into the Initial system represent the complete mineralogy of the basalt? Are they all in equilibrium with the initial porewater? Usually you include minerals in equilibrium with the porewater in the Initial pane. Minerals that are present but not in equilibrium can be set with kinetic rate laws on the Reactants pane. Then the infiltrating boundary fluids can react with those equilibrium and kinetic minerals. Adding the oxide components of the rock as simple reactants, as you've done, is much less common. And if you're just duplicating the composition of rocks in the Initial pane, you probably don't need to do it. I'm not sure what you mean with the ??? for minerals. I don't see that in your script anywhere. If you'd like to work on this script a little more and have someone take another look, please attach your custom thermo dataset as well. Regards, Brian Farrell Aqueous Solutions LLC
  13. Good day to you all, I have been wrestling with a question of H+ production by anodes in stagnant water. I have been asked to look at whether the pH 10 cm from the anode will drop below 4. I decide to start with a simplified situation, disregarding OH- production at the kathode (some 1.2 m away). The idea is that only diffusion will play a role in the distribution of H+ in this case However, the tutorial showing the effect of diffusion only starts with a local spike in concentration which then diffuses into the fluid. Is it possible to simulate a continuous addition of h+ ions to water? I tried making an inlet fluid with the desired h+ concentration, however, in reality no water is actually flowing into the system. If I do this i need to have an inlet on both sides of the simulation as well, this is confusing to me (same as left). Another thing I'm interested in is potential buffering by HCO3- in the fluid. If you have any suggestions i'm eager to learn more about this! I've added my feeble attempts at visualising the process in x1t and x2t. pH situation.x2t GWB pH prod x1t.x1t
  14. Hi, I am trying to model the flow of a brine into a basalt using x1t. I have read the documentations in React and x1t but must be doing something wrong. I thought I had to enter all the elements in Initial as well as Fluids tab. In the Initial, I added the fluid composition and the mineralogy of the basalt the fluid will flow through. In the fluid pane I copied the initial pane, but unswap the mineralogy and reduced their concentration as I only want the fluid composition here. In the reactants pane I added the composition of the basalt as oxide (wt%). Well not surprisingly, it doesn't converge. When I look at the command pane, I have many "???' for values I added for the minerals, and also for the fluid composition. Why is that? Do I need to equilibrate the fluid and the rock in the initial pane first in react then import the results? Any help with setting this up would be much appreciated. Attached is the file. Kind regards Coralie Tholeiitic-basalt-simple-brine.x1t
  15. Melika Sharifi

    Permeability Alteration

    Hello, Thanks for attaching your scripts. From your scripts, it looks like the concentration of some elements in the inlet fluid, such as silica SiO2(aq), is too high for seawater. Please double check the concentration of all elements and make sure you are using the correct unit. Hope this helps. Bests, Melika Sharifi Aqueous Solutions LLC
  16. MMichael

    Permeability Alteration

    Hello Ms Melika, I tried to simulate seawater injection into a geothermal reservoir in X1t, with a view to determining porosity and permeability alterations, if any. However, the simulation did not converge. Please find attached scripts for the model; both are similar, just slight differences in water compositions. Could you have a look and let me know what might be wrong. Kind regards. Seawater Injection_2.x1t Seawater Injection.x1t
  17. dan saalfeld

    GWB activation problem in Win10

    Hi Cycas, That seems very unusual. Do you have GWB installed on a local hard drive or a networked drive? If you could take a screenshot of the GWB Activation Utility and send it to support@gwb.com that may help us diagnose the issue. Thank you.
  18. Melika Sharifi

    Permeability Alteration

    Hello, In x2t, to plot porosity or permeability(along x or y), you can either plot them as a color map to see their variations over the domain at a specific time step. Or, you can plot them VS. time or position as an XY plot. Hope this helps. If you need more assistance, please attach your script so I can take a closer look at it. Thanks, Melika Sharifi Aqueous Solutions LLC
  19. Hi Forum Moderator, I would like to model permeability alteration in a geothermal well caused by the rock-water interaction, i.e.mixing of injection and formation waters, as well as their interaction with host rock. I noticed that with the the X1t and X2t applications, this may be possible, having gone through the tutorials on 'How do I set the Permeability?' and 'How do I account for domain heterogeneity?'. Both of these tutorials come close to what I would like to model but I cannot seem to find how to come up with a plot that depict how the porosity and/or permeability has changed due to the reactions of rock and fluids. Could you guide me. Kind regards
  20. Hello, I recently moved GWB Standard 11 from Win8 to Win10 Enterprise (version 10.0.17134 Build 17134) by deactivating in Win8 and then activating in Win10, and then I have experienced a problem. Every time I started GWB main GUI, all modules were disabled showing grey color. Then I clicked Activate GWB in Support, it responded extremely slow, typically taking 10+ min to open and once it was opened, it showed 'not activated'. But, I did not deactivate it every time I finished using GWB. What is more interesting is that, once the activation window was opened showing 'not activated' all the modules could be used as usual without clicking 'Activate'. And once I closed the activation window and opened it again it showed 'Activated'. How this issue can be solved? Many thanks.
  21. Hi all, I use X1t and X2t to predict phosphate concentrations from both dissolution reactors and within groundwaters. These models include lots of parameters, all of which have uncertainty associated with them. However, I am not sure how to estimate the uncertainty on the phosphate concentration that the RTM predicts. I could calculate it by propagating the error through the fundamental equations that the RTM use (SI, advection, dispersion, etc.), but I was wondering if there is a more straight-forward method through? Thanks for your help, Sam Bingham
  22. Melika Sharifi

    Activation code not working

    Hello, I'm sorry to hear about your laptop. I've reset your license from our end. You should be all set to activate your license on your new laptop. Bests, Melika Sharifi Aqueous Solutions LLC
  23. Melika Sharifi

    Cannot paste GSS data into excel

    Hi Polo729, We are not sure what the problem could be. Please make sure that when you want to paste your data into Excel, you single left-click on a cell to select the cell. If you double click on a cell, and then paste your data, all your data will be pasted in that cell. Please let us know if you keep having any issues. Thanks, Melika Sharifi Aqueous Solutions LLC
  24. Hey, My activation code was not working on my new laptop since my former laptop was stolen. How am I suppose to do next- i get this error code 2875-362480 Kindly assist me please. Regards
  25. I am trying to paste my GSS data into excel but it doesn't deliminate each individual cell from GSS. It simply pastes it all in one excell cell when I want it to display each data point in a separate cell. I have never had this issue in the past
  26. Thanks Brian. Once again, with the issues solved it all seems so silly. Hindsight = 20/20!
  27. Glad to hear you're up and running now. Cheers, Brian
  28. I can copy anything and everything at this point. The lack of default setting for Parallels to allow Mac clipboard access was the bottleneck. Although originally a very irritating situation, it turns out to be simple. Hindsight = 20/20.
  29. Can you copy a single cell's value from Excel into a single cell in GSS?
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