[reflux dolomite modeling]

In the pick up reactants command do you recommend picking up the entire system? When I pick up the entire system the minerals do not show up...

thanks

 

Hi Rosario:

 

1. Titrate aragonite and calcite (Reactants) into seawater (Basis)
   
2. Use the Run- Pickup- Reactants command to add this mixture to your Reactants tab
   
3. Load your new fluid into the Basis using the File- Open command
   

 

Hope that helps,

 

Tom Meuzelaar

RockWare, Inc.

[reflux dolomite modeling]

I am trying to model reflux dolomite. I first mix seawater with aragonite and calcite. I want know to pick up the results of that model and mix them with a new fluid (in the basis) I am not sure how to do this second part.

[modern seawater and kinetic carbonates]

Hi Rosario:

 

I don't think the rate parameters are entirely behind the issue- kinetics is still driven by equilibrium. In your model, initial equilibration of seawater with calcite and aragagonite drives both minerals from undersaturation (dissolution) to supersaturation (precipitation). Given that the kinetic rates for both are identical, the mineral with higher thermodynamic stability (calcite) precipitates. Additionally, the rates you've set are so high that the model proceeds according to equilibrium and you have simple conversion of aragonite to calcite.

 

I would fix this model by looking at two issues:

 

1. set realistic kinetic rates for calcite and aragonite for the timeframe you've specified.

2. try to set up initial equilibrium between seawater and aragonite/calcite in such a way that they are not initially supersaturated.

 

I hope that helps,

 

Tom Meuzelaar

RockWare, Inc.

 

 

 

Tom,

thank you. In order to do #2 would you run the model without the kinetic to equilibrate it. then pick up the fluids and interact it with the rocks again??? The kinetic rates are a problem because there is limited info. since it is always assumed that they are at local equilibrium.

[modern seawater and kinetic carbonates]

modern seawater sed kinetic.rea

 

Tom,

Thank you

[modern seawater and kinetic carbonates]

I am trying to model the modern carbonate banks by mixing modern seawater composition with aragonite and calcite. The results I am getting are not what we see in modern carboante banks. I am using calcite kinetic rates for both calcite and aragonite. One problem that I have is that all the kinetic rates are in mole/m2 s and surface area in m2/g. In react all units are in cm2. If I don't change the units the model runs but is not realistic if I convert the units the model does not converge. The expected results should be the precipitation of dolomite and anhydrite and calcite dissolution. Thanks

[kinetics]

I am trying to run a kinetic model but I am a little bit confused. When I run react my model produces certain minerals, now for the second step I want to put kinetics to see if those minerals will indeed precipitate in the long run. Do I need to put those minerals in my reactant pannel and put a small volume. I would appreciate any help.

 

thanks

[iron oxide]

what does the © in FeO© stand for?

[mixing fluids]

Tom

Thank you

[mixing fluids]

Hi Rosario:

 

The key is to use the Pickup command. The following general set of steps works for all fluid mixing models:

 

• Load water 1 into the React Basis panel
  
• Speciate water 1
  
• After React converges, "pick up" the speciated fluid via the Run - Pickup - Reactants option (you can pick up the entire speciated system, or the fluid or mineral components only). This will load water 1 component masses into the Reactants pane after speciation.
  
• Load water 2 into the Basis pane
  
• To set a mixing fraction, use the reactants times option in the Reactants pane
  

 

The above instructions are for titrating water 1 into water 2. If you want to run the reverse mixing model, simply reverse the order.

 

I hope that helps,

 

Tom Meuzelaar

RockWare, Inc.

[mixing fluids]

I am trying to mix seawater with a well water in react, how do you go about it?