Question about adding Exchange and Surface in previous modeling results

[Jeonghwan Hwang]

I want to do a modeling where the water mass increases with time.
In my model assumption, as the water mass increases, the amount of 'Exchange' and 'Surface', and 'Mineral' increase together.

At first, I conducted the model 0.1kg of water mass and 0.2kg of water mass, respectively with the concept of snapshot.

Next, I want to perform the kinetic concept. When the 0.1kg of water and mineral were equilibrated, I want to add 0.1kg of non-reacted water and non-reacted mineral and re-calculated to equilibrium at 0.2kg of water-mineral condition.

I can add the solution by using 'MIX'
However, 'Exchange', 'Surface', and 'Minerals' could not use 'MIX'.
Can I ask how to add a new value to the existing equilibrium value.
Is it best to use Exchange_Modify or Surface_Modify?

Thank you
Sincerely,

Jeonghwan Hwang

===============================================================
DATABASE C:\PHREEQC\database\PHREEQC.dat
     EXCHANGE_MASTER_SPECIES
        Z   Z-
     EXCHANGE_SPECIES
        Z- = Z-
           log_k   0.0
        Z- + Na+ = NaZ
           log_K 0.0
        Z- + K+ = KZ
           log_k 0.6
        2Z- + Ca+2 = CaZ2
           log_k 0.41
        2Z- + Mg+2 = MgZ2
           log_k 0.34
     SURFACE_MASTER_SPECIES
        Mont_wa   Mont_waOH
        Mont_wb   Mont_wbOH
     SURFACE_SPECIES
        Mont_waOH = Mont_waOH
        log_k 0
        Mont_waOH + H+ = Mont_waOH2+
        log_k 4.5
        Mont_waOH = Mont_waO- + H+
        log_k -7.9
        Mont_wbOH = Mont_wbOH
        log_k 0
        Mont_wbOH + H+ = Mont_wbOH2+
        log_k 6.0
        Mont_wbOH = Mont_wbO- + H+
        log_k -10.5
     SELECTED_OUTPUT
        -reset false
        -file 1_3_3_1.txt
        -solution true
        -time true
        -pH true
        -pe true
        -Temp true
        -water true
        -totals Na K Mg Ca C(4) Si Fe(2) Fe(3) S(-2) S(6) Cl O(0) H(0)
        -equilibrium_phases Calcite Dolomite Gypsum Quartz Siderite Pyrite
        USER_PUNCH
           -headings Mont_waO- Mont_waOH Mont_waOH2+ Mont_wbO- Mont_wbOH Mont_wbOH2+ NaZ KZ CaZ2 MgZ2 CO2(g) O2(g) Ntg(g)
        10 PUNCH MOL("Mont_waO-") MOL("Mont_waOH") MOL("Mont_waOH2+") MOL("Mont_wbO-") MOL("Mont_wbOH") MOL("Mont_wbOH2+") MOL("NaZ") MOL("KZ") MOL("CaZ2") MOL("MgZ2")
        20 PUNCH SR("CO2(g)") SR("O2(g)") SR("Ntg(g)")
        end
     end
     SOLUTION 0
        units mol/L
        pH   7.2
        pe   -2.42
        Temp   15
        C   2.20E-03 as HCO3
        Ca   2.33E-02
        Cl   1.53E-01
        Fe   3.31E-05
        K   8.75E-04
        Mg   9.30E-03
        Na   8.88E-02
        S   6.80E-03 as SO4
        Si   1.85E-04
        -water 0.1
     EXCHANGE 0
           NaZ   0.45779
           CaZ2 0.057223
           KZ 0.012716
           MgZ2 0.025433
     SURFACE 0
        -sites_units absolute
        Mont_waOH 0.03391
        Mont_wbOH 0.03391
        no_edl
     EQUILIBRIUM_PHASES 0
        Quartz   0   0.70646
        #K-feldspar 0  0.21346
        Pyrite    0   0.0049514
        Gypsum     0   0.043634
       Calcite     0  0
       Siderite     0  0
       Dolomite     0  0
   Save Solution 1
   Save Exchange 1
   Save Surface 1
   Save Equilibrium_Phases 1
     END

     MIX 1
     0 1
     1 1
     Save Solution 2
     end

     #Summation of EXCHANGE 0 and EXCHANGE 1
     #Summation of Surface 0 and Surface 1
     #Summation of Equilibrium_Phases 0 and Equilibrium_Phases 1

===============================================================

[dlparkhurst]

I am not exactly sure what you have in mind, nor the physical situation that you are modeling.

Here is my interpretation of what you have described. RUN_CELLS; -cell 1 causes solution 1 and all of the reactants numbered 1 to react and then, after the reaction, all reactants are saved to user number 1.

There are _MIX keywords for all of the reactants, including SOLUTION_MIX. The difference between SOLUTION_MIX and MIX is that no reaction calculation occurs for SOLUTION_MIX.

There are _MIX keywords for all of the reactants, including SOLUTION_MIX. The difference between SOLUTION_MIX and MIX is that no reaction calculation occurs for SOLUTION_MIX. So, the _MIX data blocks cause the reactants numbered 0 to be added to the reactants following reaction, and then RUN_CELLS reacts everything again and re-stores it in user number 1.

To continue adding more of the 0 reactants, you would repeat the _MIX and RUN_CELLS with everything accumulating in cell 1.

Code: [Select]

EXCHANGE_MASTER_SPECIES
    Z             Z-           
EXCHANGE_SPECIES
Z- = Z-
    log_k     0
Na+ + Z- = NaZ
    log_k     0
K+ + Z- = KZ
    log_k     0.6
Ca+2 + 2Z- = CaZ2
    log_k     0.41
Mg+2 + 2Z- = MgZ2
    log_k     0.34
SURFACE_MASTER_SPECIES
    Mont_wa       Mont_waOH   
    Mont_wb       Mont_wbOH   
SURFACE_SPECIES
Mont_waOH = Mont_waOH
    log_k     0
H+ + Mont_waOH = Mont_waOH2+
    log_k     4.5
Mont_waOH = Mont_waO- + H+
    log_k     -7.9
Mont_wbOH = Mont_wbOH
    log_k     0
H+ + Mont_wbOH = Mont_wbOH2+
    log_k     6
Mont_wbOH = Mont_wbO- + H+
    log_k     -10.5
END
SOLUTION 0-1
    temp      15
    pH        7.2
    pe        -2.42
    redox     pe
    units     mol/l
    density   1
    C         0.0022 as HCO3
    Ca        0.0233
    Cl        0.153
    Fe        3.31e-005
    K         0.000875
    Mg        0.0093
    Na        0.0888
    S         0.0068 as SO4
    Si        0.000185
    -water    0.1 # kg
EXCHANGE 0-1
    NaZ     0.45779
    CaZ2    0.057223
    KZ      0.012716
    MgZ2    0.025433
SURFACE 0-1
    Mont_waOH    0.03391
    Mont_wbOH    0.03391
    -no_edl
EQUILIBRIUM_PHASES 0-1
    Calcite   0 0
    Dolomite  0 0
    Gypsum    0 0.043634
    Pyrite    0 0.0049514
    Quartz    0 0.70646
    Siderite  0 0
    #K-feldspar 0  0.21346
KINETICS 0-1
 Calcite
 -tol   1e-8
 -m0    3.e-3
 -m     3.e-3
 -parms 1.67e5   0.6  # cm^2/mol calcite, exp factor
 -time  1 day
END
RUN_CELLS
-cell 1
END
# Repeat from here
SOLUTION_MIX 1
    0    1
    1    1
EXCHANGE_MIX 1
    0    1
    1    1
SURFACE_MIX 1
    0    1
    1    1
EQUILIBRIUM_PHASES_MIX 1
    0    1
    1    1
KINETICS_MIX 1
    0    1
    1    1
END
RUN_CELLS
-cell 1
END
# Repeat to here


[Jeonghwan Hwang]

Thank you very much

It helped a lot.
In addition, we will set up the model conditions precisely in light of  your comments.

Sincerly,
Jeonghwan Hwang