Re: PHREEQC

["David L Parkhurst" <dlpark@xxxxxxxx>]

The unexpected result is the reaction of N2 with O2 to make nitric acid and
the low pH.

There are entries in the mail archive
https://wwwbrr.cr.usgs.gov/projects/GWC_coupled/phreeqc/mail related to the
partial equilibrium system. See particularly an entry related to Yves Dudal
for an example of how to disconnect nitrogen gas from equilibrium with
nitrate and oxygen.

David


David Parkhurst (dlpark@xxxxxxxx)
U.S. Geological Survey
Box 25046, MS 413
Denver Federal Center
Denver, CO 80225

Project web page: https://wwwbrr.cr.usgs.gov/projects/GWC_coupled



                                                                                                                   
                      "Pedro Chambel Leitao"                                                                       
                      <pedro.chambel.maretec@xx        To:       "David L Parkhurst" <dlpark@xxxxxxxx>             
                      guspark.pt>                      cc:                                                         
                                                       Subject:  PHREEQC                                           
                      05/22/03 08:49 AM                                                                            
                                                                                                                   
                                                                                                                   




Dear David L Parkhurst,

I want to simulate pure water in equilibrium with atmosphere (see example
below).

When I run the example I get a reduction of pH from 7 to 2.

Where is my mistake?

PS: Is there any discussing group of PHREEQC

Best regards

Pedro Chambel Leitao
~~~~~~~~~~~~~~~~~~~~~~~~~~
IST - MARETEC
Taguspark
Nucleo Central, Sala 363
2780-920 Oeiras, Portugal
Tel.: +351 21 4239016
Fax:  +351 21 4211272
URL:  http://www.mohid.com



TITLE Test
SOLUTION 1 Seawater
    temp      25
    pH        7
    pe        18
    redox     pe
    units     mol/l
    density   1
    -water    1 # kg
GAS_PHASE 1 Atmosphere
    -fixed_pressure
    -pressure 1
    -volume 1
    -temperature 25
    CO2(g)    0.0003
    O2(g)     0.2
    N2(g)     0.7797
SAVE solution 1
END

-----Original Message-----
From: David L Parkhurst [mailto:dlpark@xxxxxxxx]
Sent: quarta-feira, 21 de Maio de 2003 14:47
To: Pedro Chambel Leitao
Subject: Re: subscribe


Ok. Your name will be added to the PHREEQC mailing list.