18 replies to this topic

[shinloo]

Dear all,

My colleague just asked me a question: why won't the fire in a flare get put out by rain? Anyone who knows please answer. Thanks.

[gvdlans]

Do you have any thoughts on it yourself?

[shinloo]

Not really. I have never thought about this before. And I only have a mere 6 months of working experience. I would appreciate it if you people post your thoughts/discussions here.

Thanks.

[Qalander (Chem)]

Dear Could we something about your and your friend's Chemical Engineering Degree/Educational Background please!

[gvdlans]

OK. If you assume the rain would extinguish the flare flame, what would be the mechanism? In other words, why would the rain (or firewater in case of a fire) extinguish the flames?

Hint: think about the fire triangle... If you don't know what the fire triangle means: www.wikipedia.org

[shinloo]

If you know the answer and are willing to tell me then I'd very much appreciate it. Otherwise, let's focus on the topic of discussion here, shall we?

[shinloo]

The fire triangle. Fuel is always there. Oxygen of course it's there. But heat, rainwater can reduce the temperature.

[gvdlans]

We're almost there...

Now compare the heat removed by the rain water with the heat input from the burning flare gases...

[Qalander (Chem)]

Although you did not repond to my requested query.

However the hint from Guidoo should help in the first place,

As long as sufficient level of 'Fire triangle' or more appropriately 'Fire Tetraheron' elements is available the flare flame should stay.

Now Fire triangle is assumed as 1)Combustile/Flammable material, 2)Oxygen to assist in combustion reaction, 3)Ignition Source/Temperature/Energy

Having said that 'Fire Tetra Hedron' is assumed the three elements abovementioned for 'fire triangle' and 4)Reaction of 'fire'

Or we mean to understand as if all the four elements as part of 'Fire tetra Hedron' are sufficiently available Flare's 'flame' shall not get extiguished;

however if conditions become non-sustainble due to lack of availability, this may get extiguished.

Hope the above helps.

[mishra.anand72@gmail.com]

Dear Shinloo

Hw r u?? cut pilot gas supply. Isolate flare gas inlet valve. Wait for flare tip temperature to come down.Why u r waiting for rain to extinguish flare??

[gvdlans]

Please STOP THIS SMS "LANGUAGE"

Did you read the original question?

[Qalander (Chem)]

Dear Guidoo Hello/Good afternoon,

I dont know who was your adressee right now!

but I did witness the Refinery Flare's Flame going off;while with my previous employers on few occassions during working as 'Shift Manager Refinery' of three refineries complex.

e.g. Once Too litlle combustibles flow, cold weather,very heavy rain and windy conditions; it had to be re-ignited with great difficulty, few other circumstance also witnessed.

Hope this helps.

[gvdlans]

Hope this helps.

Hello Qalandar,

Not really.

I was addressing the original poster, Shinloo. What I tried to do in this thread is helping Shinloo to find the answer himself. That's why I wrote "we're almost there".

Of course there can be exceptional circumstances where a flare flame can be put out by heavy wind and/or rain. For a well designed and operated flare tip this should be a very rare event.

By the way, I doubt whether rain alone can put out a flare unless it is very badly designed/operated.

[Qalander (Chem)]

Thanks, and I am of the same opinion indeed!

[Qalander (Chem)]

Just a minor edition; Sometimes the original design parameters& related weather data are either poorly attributed/ selected/ provided; that definitely leads to similar problems.

There have been/are circumstances while Idle capacity of flare(s) is tapped but a requisite thorough HAZOP to determine'worst case credible scenario' is not done as due.

Hope this proves useful.

[djack77494]

Like many other readers and responders, I am awaiting reply by shinloo. As Guido has said, you are nearly there. A bit more thinking on your part and you'll have it. When you said, " But heat, rainwater can reduce the temperature", I thought you had it. Try to get a bit closer to qualifying this and you'll have your answer as well as the satisfaction of having figured it out yourself.

[shinloo]

Hi all,

Thanks very much for your inputs. Very informative indeed.

Actually when Gvdlands told me to look for the fire triangle I knew what he was trying to tell me. I just thought that if that was the case, the fire could still be extinguished if the conditions (eg. flowrate of gas, heavy rain etc.) are not right. Now that you guys had cleared my doubts, thanks a lot. =)

Qalander, when the flare was extinguished did the whole refinery had to be shut down?

p.s. I had posted another question about HYSYS simulation in "PROCESS SIMULATION" forum. Please do take a look. Thanks.

[Qalander (Chem)]

Hi all,

Thanks very much for your inputs. Very informative indeed.

Actually when Gvdlands told me to look for the fire triangle I knew what he was trying to tell me. I just thought that if that was the case, the fire could still be extinguished if the conditions (eg. flowrate of gas, heavy rain etc.) are not right. Now that you guys had cleared my doubts, thanks a lot. =)

Qalander, when the flare was extinguished did the whole refinery had to be shut down?

p.s. I had posted another question about HYSYS simulation in "PROCESS SIMULATION" forum. Please do take a look. Thanks.

Not Really, within few minutes Our team got this re-ignited in spite of very heavy rain and chilly conditions in my physical presence on-site;

Two or Three attempts had to be made by the responsible operating staff (Hurrah! for their effort) .

We also had another Sky flare (Non-extinguished) of smaller capacity ready for emergency line-up purpose if the First one could not be put on or otherwise other(May be a Shut Down) decision

Hope this helps.

[shinloo]

Very informative indeed.
Thanks very much to everyone.