Controlling the fire triangle and explosion pentagon
For a fire to occur three elements of the fire triangle must be present: fuel (gas, dust ...), the oxidant (oxygen in air) and the activator (heat). For an explosion to occur other two elements must be present: containment (mill, filter, silo) and an ignitable dust cloud. The fuel and the activator cannot be removed from the equation, but the oxidant can. That is principle upon which Yara’s inert gas injection systems operate.
Inert gases have the property of being unresponsive and by replacing the oxidant they reduce oxygen levels to below critical concentration thresholds. The use of inert gases can prevent the ignition of dusts, gases or vapours and prevent oxidation and moisture absorption of certain sensitive products.
Materials used: inert gases
Inert gases listed below are used in Yara inerting processes:
- Carbon Dioxide
- Flue Gas
- Noble gases
Combustion gases and / or steam can be used in most applications, but are not available in the start-up and shutdown phases of industrial facilities. In practice, carbon dioxide (CO₂) and nitrogen are most often used. CO₂ is the most often recommended because it is easier to store.
Yara fire prevention and explosion prevention inerting technology is based on the precisely controlled injection of inert gases such as carbon dioxide (CO₂) and N₂.
For example, during the normal operation of a coal pulverizer, inerting is naturally provided by the combustion gases from the furnace. In the event of a technical problem or during start-up or shutdown, the coal mill will be free of inert gases. It is in these cases that Yara offers an additional source of reliable inert gas to secure your industrial installation and its employees.