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Most effective chemical mixer to invert petroleum flammability?

Most effective chemical mixer to invert petroleum flammability?

Hi guys,

New to this forum, and seeking some answers for a current dilemma I have with a large storage of petroleum.

I would like to know if there is any kind of chemical that when petroleum is exposed to it, (in small amounts ideally), causes the petroleum to lose its flammable vapours.

Or if there is a way of easily treating petroleum to make it less flammable?

I was thinking of the obvious at first, with causing dilution using water etc or injection of insulating chemicals such as those in foam fire extinguishers etc.

Any help would be greatly appreciated.


RE: Most effective chemical mixer to invert petroleum flammability?

It sounds like you have been "sent on a Fools errand". A fools errand is where someone tells you to go to the tool supply room and get a "left-handed pipe wrench" and a "bucket of steam". Yes, they don't exist.
Except for a nitrogen purge to a closed tank a "chemical that when petroleum is exposed to it, (in small amounts ideally), causes the petroleum to lose its flammable vapors" does not exist.

You did not include enough information about your problem or situation so it is hard for us to offer any real help.

prognosis: Lead or Lag

RE: Most effective chemical mixer to invert petroleum flammability?

I am aware of what a fool's errand is.

I want to be able to make petrol fire-proof. Sounds idiotic.(I know)

I have a petrol tank...a huge one. And it is in a Hazardous area with exposure to ignition sources.

I need to somehow treat the petrol whilst still in the tank, to make it 'flame proof' or at least reduce the amount of vapours to a level which cannot ignite at room temperature? I don't know how this can be done.

As I stated, there is a little room in the tank to inject another liquid or I was hoping that I could do either make a reaction with the petrol or to mix and dilute the petrol.

The petrol will be dumped and not used again, so it does not matter if it renders it useless.

really lost with this???

RE: Most effective chemical mixer to invert petroleum flammability?

1) Burn it off. It's what they do with flammable gasses at well heads. Add a pipe to carry the material a distance far enough away that ignition at the burn point won't drive back to the tank.
2) Put a big fan on it drive the fuel to air mixture from too rich to burn (currently) to too lean to burn and dissipate the vapors - watch out for the intermediate just-right phase.

3) Leave a little hole with a check valve so that air can't get in, and whatever vapors escape are diluted fast enough to be too lean to ignite.

As real a concern as it is, it does sound like a fools errand - how to make a gas that can burn in an atmosphere with plenty of oxygen into one that can't. If it was easy the Hindenberg line would still be in operation. They chose method 1.

If you had other means available, like being able to pressurize the material, you could do something like is done with acetylene. Self-explosive at very low pressures, it is stored in high pressure tanks by being dissolved in acetone, effectively changing the phase. I don't know of any petroleum products that self-explode, so there would not need to be a liquid to dissolve in.

You could also drop the temp of the gas so the vapors recondense. Methane boils at -164C, so -200C is all the lower you'd really need to go.

RE: Most effective chemical mixer to invert petroleum flammability?

it is in a Hazardous area 

Is the area classified (hazardous) on account of the tank?

What is your goal in eliminating the fumes? Are you hoping to reclassify the area so that the ignition sources are allowed?

RE: Most effective chemical mixer to invert petroleum flammability?


Lets just go over this to see if I've got it right.

You have a tank of petrol? or some other petroleum product? "huge" or "large" - How large. Your "huge" may not be the same as mine...

You have a "Hazardous area with exposure to ignition sources" - Please tell me where this is so I can make sure I never go there. It does not sound at all safe from your description.

What sort of tank? Sealed, open, fixed roof, floating roof, flexible membrane - what??

The only way you can reduce vapours to below LFL is cool the liquid to near freezing point to reduce the vapour pressure to negligible amounts, vent the gas at high rates with air or (preferably) introduce inert gas (CO2 or Nitrogen. Some ships etc use exhaust gas from engines to do the same thing, but that's fraught with other difficulties...

"The petrol will be dumped and not used again" What?? How can you afford to dump "huge" volumes of petrol and dump doesn't sound very environmentally friendly to me...

Remember we only know what little information you tell us - with no real data this post won't go much further as you are looking for something which doesn't exist in terms of a liquid additive, but there are ways to deal with vapour.

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

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