Mixture flammability calculation

[Camarena]

I´m running a simulation of a purifiaction process, where I have,oxigen, propane, propilene, propilene oxide and methanol at the top of the distillation column.
I would like to know if there is any formula or graphic to calculate de flammability of this mixture at pressure and temperature conditions.
How can I calculate the maximum percentage (w) of oxigen allowed in the mixture to work on safety conditions.
Any suggestions...?

 

[SooCS]

Le-Chartelier Rules of mixing:

1/Qm = Sum (yi/Qi)

where Qm =the flammability of mixture
yi = flammability of individual component
Qi = flammability of the individual component.

 

[SooCS]

Looking into the Loss Prevention in Process Industries by Frank Lee,
increase the temp increases widen the gap between LFL and UFL.
increase the pressure widen the gap between LFL and UFL event more.

How much oxygen do you have in the system? The oxygen content also affect the flammable limits.

The flammable limit equations (LFL & UFL) as the function of the temp are provided in the above ref.

 

[25362]

SooCS is absolutely right. MOCs (minimum oxygen concentrations) are proportional to LFL. LFL drop with higher temperatures, widening the flammability range. Thus at higher temperatures the MOCs also come down.

Peroxides have a lower activation energy or higher chemical reactivity. As an example ethylene oxide explodes when contaminated by ammonia. I'd recommend to carry out explosivity tests to gather data on the various vapour mixtures likeable to be encountered in the plant. There are apparatus for such testing that measure the pressures and temperatures as function of time, developed upon ignition by a spark. I pressume there are companies offering this service.

Besides, on condensation, mists having droplets of diameters lower than 0.01 mm act as vapours regarding flammability, and are of more concern if the droplets accumulate static electricity.