If the handled dust is potentially combustible or explosive, a thorough risk assessment is recommended. This includes the process to which the dust collector is applied as well as the area in which the dust collector is installed, in order to mitigate risks for people and to avoid equipment and facility damage in case of a dust explosion. The results of the hazard analysis allow us to determine the required level of fire and explosion protection.
Explosion protection systems for dust collectors are broadly divided into two groups:
- Passive explosion protection
- Active explosion protection
Passive explosion protection systems rely on the pressure generated during the early stages of explosion development to cause mechanical movement. For example, explosion relief vents which are part of the vessel of a dust collector, open at a predetermined pressure to relieve the explosion pressure and the flame front to a safe area.
In contrast, active explosion protection systems utilize optical or pressure detectors, which in case of an incident trigger an electrical circuit to cause the rapid actuation of an explosion protection device, such as chemical isolation, chemical suppression or fast-acting valves.
When considering what technique works best for which process, it very much depends on the individual application. But make sure the determined equipment is certified to ATEX or in compliance with NFPA, to be in line with local legislation.