Yes, is it possible to reach very low pressure in a flare network.
Therefore the oxygen in air can escape from flare tip back to flare header and causes explosion, especially in petroleum & petrochemical flare systems.
In this case we have to add a sealing system (gas or water) to be installed at flare header between KO Drum and flare tip to make a postive pressure inside the flare header.
Thanks,,,
__________________
It is better to be defeated on principles, than to win on lies!
Of course Abdel Halim in our flare network we have a purge of gas through the flare header, but when the instrumentation guys put the pressure gauge they find very low pressure but not all time, only from time to time, is it true or the gauge is not good.
If it's true I think that there are some phenomenones happen at flare tip like the effect of ejector to create vaccum!!!
Burning of the flare gases makes it hotter and lighter and rise up which causes an evacuation inside flare header. This vacuum is very low and can be measured by suitable gauges.
This vacuum causes the oxygen in air to inter into flare header which can cause a fire with explosion inside the flare header.
Therfore we recommend to furnish the flare tip with a retention ring around its inner surface at the upper point, which eliminate the oxygen escaping back to flare header.
Thanks,,,
__________________
It is better to be defeated on principles, than to win on lies!
Use a fine metal mesh as in davy lamp to prevent explosive mixing at low pessure.
This must be at the top of the flare stack and placed so as to be between the flame and the gas out let. Never need worry about flash back.
__________________
There's them that knows and them that just thinks they know, whitch are you? Stir the pot and see what rises up. I have catalytic properties I get a reaction going.