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Transformation from Static Leaching to Dynamic Leaching Via Kinetic Flow Term
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Topic: Transformation from Static Leaching to Dynamic Leaching Via Kinetic Flow Term (Read 237 times)
jLi200H
Contributor
Posts: 8
Transformation from Static Leaching to Dynamic Leaching Via Kinetic Flow Term
«
on:
November 15, 2018, 12:44:04 PM »
Hello,
I have been working on a static glass leaching model where there are many different components leaching into a stationary solution of deionised water. This works well, and I now want to implement a kinetic flow term within the KINETICS data-block to represent dynamic leaching. Unfortunately, I've been having problems implementing this flow term, which I'd like to implement for each species i as dCi/dt = q*(C_in,i-C_out,i)).
I've given a simple example below, which represents the basic aspects of my model. This model is unrealistic, but I just want to check that my general approach is OK. The differences between my working static leaching and my not working dynamic leaching model are the addition of a kinetic flow term. So, please can you check that I'm implementing this term correctly. In this model, this is seen by the addition of FLOW_Al and FLOW_B terms in KINETICS and RATES.
In the full model, my pH and species concentrations as a function of time give approximately correct profiles although wrong values. Please can you advise me on what my problem might be?
Many thanks in advance.
SOLUTION 1
temp 80
pH 6.13 charge
redox O(-2)/O(0)
units mol/kgw
O(0) 1.0e-5 O2(g) -0.679
-water 0.190
SAVE solution 1
END
# Sim 2
USE solution 1
#EQUILIBRIUM_PHASES 1
#...
KINETICS 1
glass
-formula B2O3 2.07e-3 Al2O3 1.64e-4
-m0 5.0
-parms 3e-8
-tol 1.0e-12
FLOW_Al
-formula Al 1
-parms 8.0903e-04 0
-tol 1.0e-12
FLOW_B
-formula B 1
-parms 8.0903e-04 0
-tol 1.0e-12
-steps 20000 in 30000 steps
-runge_kutta 6
INCREMENTAL_REACTIONS true
RATES
glass
-start
60 moles = parm(1)*time
70 SAVE moles
-end
FLOW_Al
-start
10 totalelement = TOTMOLE("Al")
30 rate = parm(1)*(parm(2)-totalelement)
40 moles = rate*time
60 SAVE moles
-end
FLOW_B
-start
10 totalelement = TOTMOLE("B")
30 rate = parm(1)*(parm(2)-totalelement)
40 moles = rate*time
60 SAVE moles
-end
END
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dlparkhurst
Top Contributor
Posts: 1384
Re: Transformation from Static Leaching to Dynamic Leaching Via Kinetic Flow Term
«
Reply #1 on:
November 15, 2018, 10:02:10 PM »
First, you need to be careful removing elements Al, B, etc. You are removing the elements, which will cause redox reactions, like the following
Al+3 + 1.5H2O = Al(s) + 3H+ + 3/2O2
As for flow, I don't understand why you do not use TRANSPORT or ADVECTION.
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jLi200H
Contributor
Posts: 8
Re: Transformation from Static Leaching to Dynamic Leaching Via Kinetic Flow Term
«
Reply #2 on:
December 12, 2018, 08:53:37 AM »
Ok thanks, will do.
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Transformation from Static Leaching to Dynamic Leaching Via Kinetic Flow Term