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Limiting oxygen concentration

Limiting oxygen concentration

Limiting oxygen concentration

(OP)
Hi

I have a question. I am working on a project where I need to find out what sort of inert gas is best to use.
I have a mixture of ethanol and air and in order to avoid an explosion it is important to determine limiting oxygen concentration. I have found data when using nitrogen as inert gas but I am more lenient to use carbon dioxide but I have not much information regarding the limiting oxygen concentration when using carbon dioxide.
can you guys help me ?

RE: Limiting oxygen concentration

adding any inert is the same, nitrogen, carbon dioxide, helium, argo, the inerting function is the same.  

RE: Limiting oxygen concentration

(OP)
Yes but I have found some data showing that when using Nitrogen the Limiting Oxidant Concetration value is different that when using carbondioxide.I just have not found any LOC values when using carbon dioxide and ethanol.

RE: Limiting oxygen concentration

Hi,

What's the application? For marine applications (tankers, FPSO's) the classification society has a upper oxygen content level on 8% (normal practice is to use 5% O2 maxi). Below 11% is considered inert. They do not differ between N2 or CO as inert gas regarding LOC.

or something like that.

RE: Limiting oxygen concentration

Nitrogen blanketing is widly used in oil refinery industry

Cheers

Luis

RE: Limiting oxygen concentration

The reason that N2 is used much more often than CO2 is that CO2 is not chemically inert.  When it dissolves in a solute, it may lower the pH, or it may raise the pH.  When it lowers the pH by forming carbonic acid it can be pretty corrosive.  When it raises the pH by forming carbonate it can affect downstream processes.

Nitrogen is not absolutely non-reactive, but it is the culprit in fewer problems.

David

RE: Limiting oxygen concentration


thread798-33615 may shed some light.

RE: Limiting oxygen concentration

CO2 is more efficient. see thread 816-162978  1 CO2 counts as much as 1.82 N2. The reason is that CO2 is a much better "heat sink" than N2. But CO2 is not quite "inert" as already pointed out.

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