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yzdm

Error: Bad Pivot

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Recently, i want to run two reactions, the second one is on the basis of the first one. After running the first reaction, i use run-pick up-system-entire, but an error occurs.

1.thumb.png.8433e0b28ee04ee3c480ac2d98c10b12.png

However, this situation doesn't occur all the time, just in a small range of amount of reactant. The reaction files and database are attached below.

I don't know what's wrong, so i am here asking for help.

 

Stage1.rea

thermo.nn.tdat

!What's more, aftering reading the content about redox pivot, i decoupled  "HS-/SO4--" and solved this problem. But the sulfide won't form in the reaction. I am not sure what happened inside.

 

 

Edited by yzdm
New thoughts maybe helpful

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Hello,

Thank you for supplying this script. There is nothing wrong with your file. Instead, we traced an issue to a linear algebra module that diagonalizes a matrix needed to set up basis swaps. The method the module uses is considered reliable, but not guaranteed. This is, in fact, the first time we’ve seen it fail.

I’ve forwarded the script to our development team and I hope to have a solution in the not-too-distant future. In the meantime, you can pick up the results by hand. You’ll want to use the current basis, rather than the original basis, from the end of your reaction path. First, go to Config -> Output and set the 3-way checkbox labeled “basis composition” to the “filled” state. You may wish to do the same for the original basis composition, for comparison. Run the model, then click “View Results” on the Results pane to open up the printed text file. Go to the end of the file to find the last step (Xi = 1), then scroll down to the section labeled “Basis components”. You’ll use the values for total moles to constrain the chemical system in a new instance of React (be sure to use the same thermo dataset, temperature, and suppressed minerals as in the original calculation). You’ll obviously need to make some basis swaps (e.g. AlO2- for Al+++, CO2(aq) for HCO3-, Chrysotile for H+, etc.). Make sure you use mol units throughout (except H2O, which must be converted to kg) and that you’re using “bulk” constraints rather than “free” constraints. You should be able to reproduce the final state of your calculation without too much effort.

We appreciate your patience as we work towards fixing this problem.

Regards,

Brian Farrell
Aqueous Solutions LLC

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Hello,
 
I’m writing to let you know about our latest maintenance release, GWB 11.0.8. The release fixes the issue you encountered with the pickup command.
 
Existing installations should automatically update to this release within the next three days, unless auto-update is disabled. In that case, you can update your installation from the Help pulldown on any GWB app.
 
I hope you enjoy using the software.

Regards,

Brian Farrell
Aqueous Solutions LLC

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