Does the flare gas fire accumulate?
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Experts, is the effect of torch gas taken into account in fire scenarios? What is the basis? Mainly looking for evidence
It seems there is a definition for the area affected by the fire, and the main regulations regarding the installation of torches are based on SH3009.
Code for Fire Protection Design of Petrochemical Enterprises GB50160, Chapter 5, Article 5.5: Pressure relief and flare systems. 5.5.21 The installation of elevated flares within the plant shall comply with the following provisions: 1. Combustible gases discharged into flares are prohibited from carrying combustible liquids； 2. The radiant heat from the flame should not pose a risk to human safety or equipment ； 3. Flammable gas vents shall not be installed within 30 m of the torch tube.
For flare gas, the maximum emission volume of the unit or tank under fire conditions is typically considered, rather than a cumulative amount.
There is no such rule in 3009
You should take another close look at how SH3009 is described
According to the provisions in standard SH3009-2013, emissions from the same accident should be added together; the principle for such addition shall be determined in accordance with the rules set out in 3009. However, when considering fires, sometimes only fires in a single unit area are taken into account, rather than a fire involving the entire plant (usually the largest unit). After all, the probability of all units in the plant catching fire at the same time is extremely low; otherwise, the amount of gas discharged through the flares would be too large, and the capacity of the flares designed for this purpose would also need to be increased, which is clearly not economical
The principle of superposition for fire conditions can be found in API520/521; it’s a circle with a radius of 25 meters, I believe