Loading FeOH+.sdat Error

[BruceW]

Working through examples on the Acid Drainage topic in the Online Academy I had no problems opening the FeOH+.sdat file. However, when working with acid drainage chemistry with site data, when attempting to open the FeOH+.sdat file I received the error message in the attached file. Any recommendations for how to fix this error would be appreciated.

[Guest Melika Sharifi]

Dear Bruce,

 

Thanks for attaching the error message.

All .sdat tedit datasets include in the Header a reference to the thermo dataset that supplied all the aqueous species and minerals involved in the surface complexation reactions. The error you are receiving is saying that As(OH)3 is not included in the thermo dataset you are using.

Hope this helps.

 

Bests,

Melika Sharifi

Aqueous Solutions LLC

[BruceW]

Thanks Melika - My question is, why do I not get that error message when I load the FeOH+.sdat file in the Acid Drainage React using the Co-precipitation.rea instructional file? The FeOH+.sdat database should be the same.

[Guest Melika Sharifi]

Dear Bruce,

 

My first thought was that you are using a custom-made thermo dataset that does not include As(OH)3. Could you, please, attach your script along with the surface dataset and thermo dataset that you are using, here? Even if you are using the GWB's dataset, please attach them here so I can take a look into them and make sure they are in a correct format.

 

Thanks,

Melika Sharifi

[BruceW]

Hello Melika,

 

Thanks for looking into this further. I have attached the .rea file I am using, and the .sdat file I am trying to load. It is the FeOH+.sdat file that was supplied with GWB Professional Version 10, and it works fine when I work with the Co-Precipitation.rea file downloaded from the Academy. I tried to set up the 170808 HDS-Lime_1.8g.rea file the same as the Co-Precipitation file with just changes to the chemical parameters and concentrations.

 

Cheers,

Bruce

FeOH+.sdat

170808 HDS-Lime_1.8g.rea

[Guest Melika Sharifi]

Dear Bruce,

 

Thanks for sharing your script.

 

As mentioned above, all .sdat datasets include in the Header a reference to the thermo dataset that supplied all the aqueous species and minerals involved in the surface complexation reactions. If you open FeOH+.sdat using TEdit, you will see its reference thermo dataset is thermo.tdat. It does not mean that FeOH+.sdat does not work with other thermo datasets; but all species in the surface dataset must exist in the thermo dataset loaded into the GWB app. The Preamble section of FeOH+.sdat offers as an example guidance for how to use the surface dataset with thermo.com.v8.R6 dataset instead of the default thermo.tdat dataset.

 

The Co-precipitation example in the GWB Academy is using thermo.tdat and FeOH+.sdat, but in your React script, you are using thermo.minteq dataset which does not have all the species and minerals in the surface dataset.

 

The solution to your problem can be any of the ideas mentioned below depending on the components present in your aqueous systems:

 

1. Change your working surface dataset to FeOH_minteq.sdat

2. Change your working thermo dataset to thermo.tdat or thermo.com.V8.R6 (for this one you have to change a few species names as mentioned in the preamble box in the Header section.

3. If FeOH_minteq.sdat does not have all the species and minerals you are interested in (it has fewer numbers of species and minerals compared to FeOH+.sdat), you can simply modify FeOH_minteq.sdat by adding species and minerals using TEdit app. Sections 9.2.3 and 9.2.4 in the GWB Essentials Guide describe how to add reactions to your thermo dataset using TEdit. All GWB guides can be accessed from the Docs pane of The GWB dashboard.

 

Bests,

Melika Sharifi

Aqueous Solutions LLC

[BruceW]

Thanks Melika.