Re: Use of PHREEQC

[Alex Carrillo <ambiente@xxxxxxxxxxxxxxxxxxx>]

> >Could PHREEQC be used for modeling petroleum brines (20,000 to 150,000
> ppm)?
> My main interest would be in speciation, SI, mixing, forward modeling and
> inverse modeling.
>
> PHREEQC has an ion-association model, which is limited to the lowest
> concentrations that you mention. The program will make calculations at
> higher concentrations, but I think the aqueous model would be suspect. You
> really need a Pitzer (specific ion interaction) model for the high ionic
> strengths. Geochemist's Workbench, EQ3/6, TEQUIL, SOLMINEQ, and PHRQPITZ
> implement Pitzer models. I maintain PHRQPITZ, but I don't advocate its use.
> It is old and difficult to run, although I am confident that it does the
> calculations correctly.


Dear David,

Many thanks for your message. I have used PHREEQC for several years in 
natural waters and in different ways ( I give a course in UNAM-major 
Mexican U¿university). But now the Mexican oil industry (PEMEX) is 
interested in the characterization of petroleum brines and their 
evolution.  Would you recommend Geochemist{s Workbench?

Thanks again for your help an time

*****************************************************
Dr. Alejandro Carrillo-Chávez
Centro de Geociencias-UNAM
Campus Juriquilla,  A.P. 1-742
Queretaro, 76230, Mexico.
Tel: + 52 (01) 442 238-1104 ext 106
Tel: + 52 (01) 555 623-4104 ext 106
Fax: + 52 (01) 442 238-1101
E.mail: ambiente@xxxxxxxxxxxxxxxxxxx
Home page: http://geminis.geociencias.unam.mx/~ambiente/
MSN messenger:  alex_carrilllo58@xxxxxxxxxxx
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