script: kinetic rate

[forrie]

Hi Brian

 

I am trying to simulate acidification over time in a column test.

Can you please tell me what is wrong with my script for a kinetic mineral below...

 

 

 

 

IF pH > 3 THEN 20 ELSE 40

20: rate = 6.4565e-13 * surface * (1 - Q/K) * (activity("H+")^-0.11) * (activity("O2(aq)")^0.5)

GOTO 60

40: rate = rate_con * surface * (1 - Q/K) * (activity("Fe+++")^0.93) * (activity("Fe++")^-0.4)

60: RETURN rate

 

 

 

Thanks

Johan

[Brian Farrell]

Hi Johan,

 

Can you explain your problem a little more? Do you receive a specific error message? Could you attach your React script and any additional files I'll need to run it?

 

Thanks,

 

Brian Farrell

Aqueous Solutions LLC

[forrie]

Hi Brian

 

When I replace the built in rate law with the script the mineral does not react.

 

I thought that maybe it is again the script that is the problem as no reaction takes place. However if I specify the first condition of the script in the built in law then it runs perfectly. But I would like to run the second condition also.

 

Regards

Johan

Column test pyr.x1t

[Brian Farrell]

Hi Johan,

 

Thanks for posting this. Hopefully next week I'll have something for you.

 

Regards,

Brian

[forrie]

Hi Brian

 

Anything yet?

[Brian Farrell]

Hi Johan,

 

I've made some progress testing the rate law scripts in simpler examples, but I'm not sure yet why your X1t example isn't working.

 

Regards,

Brian

[Brian Farrell]

Hi Johan,

 

We've found a small error in the rate-law parser when reading pH. This will be fixed in the next maintenance release. In the meantime, I think you can use the rate-law scrip below in its place. Be sure to verify that it is behaving as you would expect it to (perhaps run a batch model).

 

IF activity("H+") < 1e-3 THEN 20 ELSE 40

20: rate = 6.4565e-13 * surface * (1 - Q/K) * (activity("H+")^-0.11) * (activity("O2(aq)")^0.5)

GOTO 60

40: rate = rate_con * surface * (1 - Q/K) * (activity("Fe+++")^0.93) * (activity("Fe++")^-0.4)

60: RETURN rate

 

Apologies for the inconvenience.

 

Regards,

Brian

[Brian Farrell]

Hi Johan,

 

Just wanted to let you know that Maintenance release 9.0.6 is out. It includes a fix for reading pH in the rate law parser, so your original basic script should work now.

 

Please let us know if you have any questions.

 

Regards,

Brian