Reaction rates and specific contact area for gases

[Neda]

Hi,

 

I am trying to set up a kinetic geochemical model that simulates injection of gas (H2) into a system composed of brine and minerals. I'd like to model the injected gas kinetically through Reactants-->Kinetic--> Gas transfer option. After reading the Gas transfer kinetics description in the Reaction Modeling Guide tutorial of GWB and doing quite a bit of research, I could not find any information about rate constant or specific contact area of the gases.

 

I am wondering if anyone has an idea of the order of magnitude reaction rates for gases as well as specific contact area. I would greatly appreciate any comments. Thank you.

 

Best regards,

Neda

[Neda]

Hi again,

 

In regards to my previous question, I'd like to make sure the entered value for kinetic gas is a fugacity coefficient. Is it correct or it is an effective pressure of gas so it needs to have a unit such as atm or bar. Thanks.

 

Best,

Neda

[Brian Farrell]

Hi Neda,

 

I don't know too much about specific values for rate constants that would be useful for you. As for the second question, you are not specifying a fugacity coefficient. Rather, you directly specify the fugacity, or effective pressure in bars, of the gas in the external reservoir.

 

Hope this helps,

 

Brian Farrell

Aqueous Solutions

[Neda]

Hi Brian,

 

Thank you for clarifying fugacity unit. Since there is no unit written in front of this parameter, it a bit confusing to understand the exact meaning of it.

 

Best regards,

Neda