The thermal impact of a flare is an important issue to be taken into consideration when designing and operating flares. The flame of a flare should be discharged at such a distance that the thermal radiation flux does not pose a hazard to the personnel both during normal operation of the installation, and in case of an emergency gas discharge.
If a flare is located near potentially explosive zones, thermal radiation generated by the flare should not cause a temperature increase up to a level exceeding the substance self-ignition temperature.
What is more, in areas where electrical explosion protection equipment is installed, the flame of the flare should not cause a temperature increase up to a value exceeding 40oC (i.e. the temperature up to which explosion protected electrical equipment is usually designed for).
In case of an emergency flare flame extinction, a large stream of flammable, sometimes even toxic gases is released into the atmosphere. A flare gas dispersion study is prepared in order to determine whether the generated gas cloud may pose a hazard for the surrounding area. Both structures located on the ground level and elevated structures on which the personnel may walk, are considered in the study. A flammable substances dispersion analysis involves the presence of ignition sources. If gases supplied to the flare include toxic substances, a toxicity hazard assessment is done as part of a gas dispersion study.
Flare thermal radiation and gas dispersion studies are mostly done at the stage of designing new and modernising existing flares. Such analyses are also required in the following situations:
On the basis of a flare thermal radiation and gas dispersion study it is possible to determine measures mitigating its negative impact on the personnel and installations (e.g. use of protective clothing, fencing-off of the area around the flare, use of water curtains during an emergency discharge).
ASE experts have the experience, know-how and tools necessary to conduct flare safety analyses (including specialist software). Mathematical models established for specific types of flares are used for the calculations. Get in touch with us if you want to learn more about flare safety.