IPhreeqc/Matlab

[omarchaabi]

Dear all,

I am trying to run some PHREEQC simulations through matlab. To clarify my question I will propose the following example. Lets say I want to initialize the following solution as follows:

iphreeqc.AccumulateLine("SOLUTION 1");
iphreeqc.AccumulateLine("   temp      25");
iphreeqc.AccumulateLine("   pH      7");
iphreeqc.AccumulateLine("   pe      4");
iphreeqc.AccumulateLine("   redox   pe");
iphreeqc.AccumulateLine("   units      mg/l");
iphreeqc.AccumulateLine("   density   1");
iphreeqc.AccumulateLine("   Alkalinity   332   as HCO3");
iphreeqc.AccumulateLine("   Ca      13840");
iphreeqc.AccumulateLine("   Cl      96560");
iphreeqc.AccumulateLine("   Mg      1604");
iphreeqc.AccumulateLine("   Na      44261");
iphreeqc.AccumulateLine("   S(6)           885");
iphreeqc.AccumulateLine("END");
iphreeqc.RunAccumulated;

According to the default settings, it will use 1 Liter of water. My question is the following, can I set a different volume of water that is already defined as a variable in matlab. I was hoping maybe something as the following would work

iphreeqc.AccumulateLine(['-water ', Saturation]);

where Saturation is a variable calculated previously in my Matlab code. But unfortunately it doesn't work. I am using my simulations in loops so it is not possible for me to define the volume of water manually. I hope someone can help or guide me to possible solutions. Thanks in advance

Regards,
Omar

[dlparkhurst]

Just to be pedantic, PHREEQC uses 1 kg water for the default in SOLUTION definitions, which may vary from 1 L of SOLUTION, especially in brines. (PhreeqcRM has methods that convert from volume to mass of water and back again.)

The -water option in SOLUTION also defines a number of kilograms of water, but again, it is usually is within a percent or two of the volume in liters.

You can definitely use -water in SOLUTION, perhaps your syntax is not correct. AccumulateLine requires a string argument.

[omarchaabi]

Thanks for the prompt reply. It was indeed a syntax mistake. I used matlab function (num2str) to convert the Saturation to a string. It worked and for anyone who might face the issue here is how it was written:

iphreeqc.AccumulateLine(['-water ',num2str(Saturation)]);