Re: PHREEQC question

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

You still need an estimate of the pe before the phase and si are entered.

   SOLUTION 1
         temp      25
         pH        7
         #pe        O2(g) -.7
         pe        10  O2(g) -.7
         redox     pe
         units     mmol/kgw
         density   1
         water    1 # kg


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


                                                                                                                   
                      "Paul S Domski"                                                                              
                      <psdomski@xxxxxxxxx         To:      dlpark@xxxxxxxx                                         
                      eering.com>                 cc:                                                              
In-Reply-To: <OF7D219FB9.D4EAE6C5-ON85256AAF.0056EBF2@xxxxxxxxxxxxx>
                                                  Subject: PHREEQC question                                        
                      08/21/01 08:56 AM                                                                            
                                                                                                                   
                                                                                                                   



Hello Dr. Parkhurst-

Question about the pe setting in the solution keyword.  It seems like pe is
not accepting a phase name & SI as valid input.  I'm probably missing
something but for example, using O2(g) -0.7 as the pe input results in the
following (I'm using a Yucca mt database).  Seems the code only recognizes
the -.7 and not the need to equilibrate the solution with O2 at logPO2 -.7.
What am I missing?

Thanks for your input.
Paul Domski



   Input file: D:\ymp_2001\High_T\test.pqi
  Output file: D:\ymp_2001\High_T\test.pqo
Database file: C:\Program Files\USGS\PhreeqcI2.3\phq_ymp.dat

------------------
Reading data base.
------------------

     SOLUTION_MASTER_SPECIES
     SOLUTION_SPECIES
     PHASES
     END
------------------------------------
Reading input data for simulation 1.
------------------------------------

     DATABASE C:\Program Files\USGS\PhreeqcI2.3\phq_ymp.dat
     SOLUTION 1
         temp      25
         pH        7
         pe        O2(g) -.7
         redox     pe
         units     mmol/kgw
         density   1
         water    1 # kg
-------------------------------------------
Beginning of initial solution calculations.
-------------------------------------------

Initial solution 1.

-----------------------------Solution
composition------------------------------

     Elements           Molality       Moles

     Pure water

----------------------------Description of
solution----------------------------

                                       pH  =   7.000
                                       pe  =  -0.700
                        Activity of water  =   1.000
                           Ionic strength  =  1.006e-007
                       Mass of water (kg)  =  1.000e+000
                 Total alkalinity (eq/kg)  =  1.135e-009
                    Total carbon (mol/kg)  =  0.000e+000
                       Total CO2 (mol/kg)  =  0.000e+000
                      Temperature (deg C)  =  25.000
                  Electrical balance (eq)  = -1.135e-009
 Percent error, 100*(Cat-|An|)/(Cat+|An|)  =  -0.56
                               Iterations  =   0
                                  Total H  = 1.110174e+002
                                  Total O  = 5.550868e+001

----------------------------Distribution of
species----------------------------

                                                Log       Log         Log
     Species            Molality    Activity  Molality  Activity     Gamma

     OH-              1.012e-007  1.012e-007    -6.995    -6.995    -0.000
     H+               1.001e-007  1.000e-007    -7.000    -7.000    -0.000
     H2O              5.551e+001  1.000e+000     0.000     0.000     0.000
H(0)            3.944e-016
     H2               1.972e-016  1.972e-016   -15.705   -15.705     0.000
O(0)            0.000e+000
     HO2-             0.000e+000  0.000e+000   -51.711   -51.711    -0.000
     O2               0.000e+000  0.000e+000   -60.803   -60.803     0.000

------------------------------Saturation
indices-------------------------------

     Phase               SI log IAP  log KT

     H2(g)           -12.60  -12.60    0.00  H2
     H2O(g)           -1.59    0.00    1.59  H2O
     Ice              -0.14    0.00    0.14  H2O
     O2(g)           -57.90   25.20   83.10  O2

------------------
End of simulation.
------------------

------------------------------------
Reading input data for simulation 2.
------------------------------------

-----------
End of run.
-----------