lea512

Ok, I think I may understand. What I was doing was running the model that contained about 9 minerals (with kinetics) for about 10 years and Quartz and Kaolinite were always supersaturated while everything else was either in equilibrium or undersaturated. So if I understand correctly, quartz and kaolinite just haven't reached equilibrium yet? Thanks for the help!! Lea

Hello again, Ok, so if the minerals in the system are in equilibrium with the fluid, what do the grams and volume of each mineral represent? In addition, I am adding CO2 into the system and sliding the fugacity which increases the acidity of the fluid, which means that I shouldn't have any minerals that are supersaturated (I am also adding in kinetic minerals and their dissolution rate). Quartz and kaolinite, however, are always supersaturated, but I have found that just adding these minerals in equilibrium eliminates this issue. Is there a better way kinetically to make it to where these two minerals are just in equilibrium or saturated in the fluid?

Tom, Thank you for the information, it really helped me out. However, I think where I was getting confused was with the "Minerals in System" results. Are these minerals that the model has predicted have precipitated along with their amounts in grams and volume (cm3)? I notice that most of the minerals within the "Minerals in the system" heading are saturated in solution. Anyway, if you could clarify what exactly the "minerals in the system" heading provides results for, that would help me out tremendously.

Thanks Tom. I have tried to suppress minerals, but I have suppressed the minerals that are supersaturated or saturated in the last step of the reaction. When I do this, new minerals are then in the system. Am I using the wrong minerals, and if so, which minerals do you suggest that I suppress?

Hello, I am currently trying out new water chemistry and mineral data in REACT (compared to a previous forum discussion). I am using kinetic data in REACT and do not want any minerals to precipitate in the reaction. However, when I turn precipitation off, the reaction path says it is abandoned and only provides results for a couple of steps. How do I not allow mineral precipitation with kinetic data? Do I need to use only equilibrium data for no minerals to precipitate? I have provided the file. Thanks, Lea 1755-1WaterChem_other SS.rea

Actually I have been using both smectites in a kinetic model. Currently, I am working with a carbon sequestration team that is in the planning/researching stages (and writing my thesis) where drilling has yet to begin and we have no data (some mineralogical). Some members on the team believe that we should forget the kinetics and just consider everything in equilibrium. Plus, I was trying to run both kinetic and equilibrium models together to compare how much the concentrations vary from model to model over a period of time. Just a thought. Do you have any suggestions (based on my input data) about how to improve my model for carbon sequestration? Also, I have no actual water chemistry data from the aquifer that we plan to inject into (the water data above is from 200+ miles away). Do you have any suggestions as to how to determine water chemistry data from using only mineralogical data? Thanks again. Lea

I attached the script. Hope it works!! Lea

Recently, I have been trying to input both high Fe,Mg-rich smectite and low Fe,Mg-rich smectite into my equilibrium model. When I input the values (in grams) that I want, I get this message at the bottom of the "Run" tab Cutting step size to find phase assemblage Swapping K+ in for Clinoptil-K Swapping Hematite in for Nontronit-Mg Swapping Mg++ in for Clinoptil-Ca Swapping SiO2(aq) in for Kaolinite Swapping Fe++ in for Pyrite Residuals too large, 661-th interation -- Didn't wake up, abandoning path However, when I change the low-fe-mg-smectite to a smaller value, it seems to work correctly. I would really like to use my value, but if I am doing something incorrectly, please let me know. I have provided my input data below to help in my explanation. Input Data: Water Chemistry H2O = 1 kg Ca2+ = 63.8 Na+ = 6.5 Mg2+ = 46.9 SO4-- = 100 Cl- = 5 HCO3- = 293 charge balance H+ = 7.5 Fe2+ = 0.11 Mn2+ = 0.05 K+ = 1.8 O2(aq) = 0.01 SiO2(aq) = 0.01 Al3+ = 0.01 Mineral Data Quartz = 1899.96 g in rxn K-Feldspar = 112.4 g in rxn Albite = 18.74 g in rxn Kaolinite = 89.91 g in rxn Illite = 1101.84 g in rxn Hematite = 67.44 g in rxn Goethite = 67.44 g in rxn Low Fe,Mg-rich Smectite = 200 g in rxn (I WANT THIS TO = 1035.61g INSTEAD!!) Fe,Mg-rich Smectite = 498.72 g in rxn Other Data Temperature = 30C Time = 0-20 years Sliding CO2 (g) Fugacity to 53.3 bar NS4C-1836-1_equil.rea