Is it considered necessary to install a flame arrester at the outlet of the on-site vent safety valve?
Thread Content
Is it considered necessary to install a flame arrester at the outlet of the on-site vent safety valve? According to clause 5.5.4 of the \"Code for Fire Protection in Petrochemical Enterprises,\" a flame arrester is not required for venting. However, in the projects we have worked on previously, flame arresters were installed on the hydrogen buffer tanks (for on-site venting). What are everyone’s thoughts on this? Should a flame arrester be considered for the on-site vent at the top of the propylene storage tank?
There is no need to install a flame arrester; if the valve is not opened frequently, a blind flange can be added.
I don’t think it’s necessary to install a flame arrester either; propylene storage tanks are not often vented to the atmosphere – generally, a flare system is used for such purposes, and venting to the atmosphere is rare
It seems unnecessary to add it. The people above have mentioned several scenarios. First, \"it’s not used frequently, so a blind flange is used.\" But when it’s necessary to vent the fluid on-site, which is more convenient: venting through a device equipped with a flame arrester or through one equipped with a blind flange?； Second, \"the flare system is rarely used for aerial discharge.\" This type of discharge is seldom utilized because, in addition to it, we can also use nitrogen sealing, or flame-arresting breather valves equipped with nitrogen sealing; the nitrogen gas generated is generally vented through flares or into the atmosphere. Installing safety valves for local discharge serves as our last line of defense, and they are activated only in very rare cases. Therefore, I believe there is no need to add flame arresters ；
There is no need to add anything; this type of storage tank is used only during operations such as purging. To prevent leaks, a blind flange or an internal threaded cap can be installed.
Propylene has a flash point of less than -108°C, and it is heavier than air, allowing it to spread over considerable distances at lower levels; it can also catch fire when exposed to an open flame. In accordance with the relevant requirements specified in HG-T 20570.19-1995 \"Installation of Flame Arresters\", I believe it is necessary to install flame arresters.
The original poster didn’t look carefully; a flame arrester is not required if the outlet pipe of the safety valve is connected to a pipeline or container, but one is necessary when venting directly.
Is a safety valve installed? If a vent pipe equipped with a safety valve is in use, there is no need to install an ignition arrester additionally, as the activation of the safety valve indicates a fault, and in such cases human intervention is required. When the safety valve does not activate, no combustible gases are released, so an ignition arrester is not necessary.
The purpose of adding a flame arrester is to prevent external sources of fire from entering the tank through the vent pipe. Under normal conditions, the safety valve is closed, so it isn’t necessary; moreover, when the safety valve activates, the pressure inside the tank is higher than the ambient pressure, so it’s still not needed. Similarly, atmospheric pressure storage tanks with a nitrogen seal may also omit a flame arrester.
For vent pipes, there are usually valves, and these valves are closed under normal conditions. According to what you say, vent pipes that already have valves don’t need flame arrestors anymore
The vent pipes for general flammable media are usually supplied with nitrogen to ensure the safety of the gas composition within the pipes.