Nitrogen sealing and nitrogen fire suppression
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I have a question for everyone’s help. I am currently working on a heat transfer oil system, and the expansion tank as well as the oil storage tank require nitrogen sealing. The gas-fired heat transfer oil furnace is equipped with nitrogen discharge ports for fire suppression. When calculating the amount of nitrogen needed, should it be the sum of the amounts required for both components, or should it be based on the larger amount? Thank you all
I think going with the larger size is fine; compared to fire suppression, the amount of nitrogen used for sealing is very small
Nitrogen for fire extinguishing: \"Fill 3 times the furnace volume in 15 minutes.\" Should the amount of nitrogen calculated based on this specification be understood as being at standard conditions?
The furnace volume is V*3 *60/15=12V; 12V represents the amount of nitrogen required for 1 hour. Should this amount be considered under standard conditions after it is introduced into the furnace? Still the operating conditions at pipeline pressure and temperature?
It should be under standard conditions. It is unclear what the basis is for these regulations regarding fire-fighting requirements. Theoretically, oil tanks that are sealed and filled with nitrogen should not catch fire; if a fire does occur, it must mean that the sealing has failed. In such a situation, the nitrogen present cannot serve to prevent ignition or suppress the fire. Since the specifications state it this way, let’s follow the specifications
Okay, thank you for the reply:handshake
Let’s see if it’s possible, with this design, to install a pressure storage tank; one circuit can be used for pressure reduction and nitrogen sealing, while another circuit for fire suppression should be equipped with a quick-acting valve (electric or pneumatic) as well as temperature interlocks. When equipped with a compressor, the amount of sealing gas is taken into consideration; the compressor fills the pressure tank to its maximum design pressure and then stops (or is unloaded), while it starts up (or is loaded) when the pressure drops below the minimum design value. One should not just think about designing one that uses the maximum amount for fire extinguishing. It’s best to visit the relevant companies to get some references.
The two are different concepts; nitrogen sealing is a preventive measure, while the latter is for dealing with accidents.