PHREEQC 3 can calculate the solubility of typical scale forming minerals like barite, celestite, halite, etc. at high pressures and temperatures. The Pitzer database that is used for calculating the solubilities has been updated, fitting interaction coefficients for the Na-K-Mg-Ca-Ba-Cl-CO2-HCO3-SO4-H4SiO4 system on many experimental data (Appelo, 2015, Appl. Geochem. 55, 62-71). The appendix to the paper contains figures showing experimental solubilities and PHREEQC calculations and can be inspected in the pdf file appendix.pdf’. All the PHREEQC input files (and the paper and appendix) can be downloaded as zip from: appendix.zip’.
A few cases are presented here, from the directory c:\phreeqc\high_P_T\salts’ that is installed by phreeqc3.Installer.exe’.
The files can be run from Notepad++ (will be installed with phreeqc3), or by starting a DOS window and typing (for example)
where Barite_NaCl.phr is the name of the file.
Barite in NaCl solutions, in Barite_NaCl.phr:
Barite at 500 bar, f(T), in Barite_tc.phr:
Celestite at 25, 100, 200oC, f(P), in SrSO4_P.phr:
Celestite at 200 bar, f(T), in SrSO4_tc.phr:
Halite at 30 °C, f(P), in halite.phr: