Phases Error

[Jestril]

Dear all,

I am a new user of PHREEQC and I am currently facing some challenges to model a water mixing scenario between seawater and formation brine.

The problem is, one of the mineral (Chlorite) in equilibrium with the formation brine seems not to be available either in the Pitzer or LLNL database.
To fix the issue, I firstly tried to create a new database as a combination of two (Pitzer and LLNL) thinking it would work but it did not.
As a second attempt, I tried to add the keyword Phases with the mineral and related information (log K and equations) but it gives me an error stating "elements in species have not been tabulated" and "reaction of species have not been defined, H4SiO4".
In my last attempt, I tried to define the H4SiO4 equations under PHASE but here again I get error messages such as "Expecting equation for phase H4SiO4. Parsing equation".

Is there anyone on the forum who had experienced the same and could debug the problem ?

In advance, thanks a lot for your input

[dlparkhurst]

I would simply add the PHASES data block to your input file so that the databases remain intact.

You can add this reaction from phreeqc.dat (using your reaction and log K if desired) for any database that uses H4SiO4 as the primary master species (SOLUTION_MASTER_SPECIES data block), which includes all databases except the llnl-type databases.

Code: [Select]

PHASES
PHASES
Chlorite(14A)
      Mg5Al2Si3O10(OH)8 + 16H+ = 5Mg+2 + 2Al+3 + 3SiO2 + 12H2O
-log_k 68.38
-delta_h -151.494 kcal

For llnl.dat and core10.dat, use the following reaction:

Code: [Select]

PHASES
Chlorite(14A)
Mg5Al2Si3O10(OH)8 + 16H+ = 5Mg+2 + 2Al+3 + SiO2
-log_k 68.38
-delta_h -151.494 kcal


[Jestril]

Dear David,

First of all, thanks a lot for your valuable input. It comes as a relief after many trials and error.

As suggested, I did try to implement the second option. However, it first gave me an error due to equation equilibrium which I was able to solve. After fixing this, now it is prompting another error stating that the phase (chlorite(14A)) is not found in database. I did try with both core10 and llnl but still get the same message.

Any thoughts ?

Thanks a lot,

Jestril

[dlparkhurst]

I need to see your input file.

[Jestril]

Dear David,

Please find below the code I am currently testing.

Thanks,

Jestril

Code: [Select]

SOLUTION 1 Formation Water at Room Temperature and Pressure
    temp      25
    pH        7
    pe        4
    redox     pe
    units     mg/l
    density   1
    Na        37780
    K         2981
    Ca        48620
    Mg        3155
    Sr        617
    Ba        303
    Si        17
    Cl        155477
    Fe        288
    S(6)      108
    Alkalinity 69
    -water    1 # kg

REACTION_TEMPERATURE 1
    135 #degC
SAVE SOLUTION 2
END

USE SOLUTION 2
REACTION_PRESSURE 1
    150 #atm
SAVE SOLUTION 3
END

USE SOLUTION 3

PHASES
Chlorite(14A)
Mg5Al2Si3O10(OH)8 + 16H+ = 5Mg+2 + 2Al+3 + 3SiO2 + 12H2O
-log_k 68.38
-delta_h -633.851 kcal
END

EQUILIBRIUM_PHASES 1
Illite 8.42E-06 #Smectite
Illite 2.42E-04 #Mica
Kaolinite 6.16E-05
Chlorite(14) 2.78E-05
Quartz 3.78E-02
K-Feldspar 6.32E-04
Albite 2.98E-04
Anorthite 2.98E-04
Calcite 2.17E-04
Dolomite 0.0
Siderite 0.0
SAVE SOLUTION 4

END

[dlparkhurst]

Your spelling needs work.

Chlorite(14A)

[Jestril]

Thanks a lot David just realized where the mistake is.

Again, thanks a lot.

Jestril