PhreeqcUsers Discussion Forum

Beginners => PHREEQC basics => Topic started by: peterwadeuk on February 23, 2021, 05:13:34 PM

Title: How to perform sequential equilibrations with Solution Spread
Post by: peterwadeuk on February 23, 2021, 05:13:34 PM
Greetings good people,

I apologise for the basic nature of this question, I haven't used PHREEQC for a while and someone asked me to help with a problem.

The attached pqi file has SOLUTION_SPREAD defined for a host of entities, some of which are not in much used databases. That is not the problem we are experiencing.

We follow up with EQUILIBRIUM_PHASES statements, and find that PHREEQC only executes the first one.

How are we bungling the format of the input?

All the best,
Peter
Title: Re: How to perform sequential equilibrations with Solution Spread
Post by: dlparkhurst on February 23, 2021, 05:53:57 PM
Yes, by default, PHREEQC will take the first solution and the first equilibrium phases (before an END) and only do one reaction calculation that equilibrates the solution with the equilibrium phases.

The trick is to use RunCells. Here is the way I set up the problem. Because all of the equilibrium phases definitions are the same, you can define them in one data block. I used lots of END statements to avoid the default reaction calculation.
Title: Re: How to perform sequential equilibrations with Solution Spread
Post by: peterwadeuk on February 24, 2021, 09:44:33 AM
Thank you very much, David.

A great day to you.

Peter