Off-Gas Collection System and Flares

The flare must be equipped with diverse safety systems to prevent flashback of the flame (e.g., water-immersion bath, flame traps, acceleration path as dynamic flashback protector). 

In the chemical industry, flares are being used less and less for off-gas purification and more as safety measures, for example, for fast pressure relief or for the disposal of harmful gases during process disturbances. 

In the last few decades numerous developments have taken place in the field of off-gas and waste-air purification. They are treated briefly in the following  

Waste air that contains only one certain pollutant can be purified by physical or chemical absorption of this contaminant in a suitable washing agent. This method is often economical in those cases in which the loaded washing liquid can be used in a process without workup. 

Adsorption exploits the capability of, for estample, activated carbon to take up large amounts of organic vapors. Very low residual concentrations can be achieved. Since this is a regenerative process, at least two adsorption toweres are required. 

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