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Strategies for

EXPLOSION PROTECTION in feed processing

Mark Shannon from BS&#38;B Safety Systems explains how to avoid basic mistakes in explosion protection installation for your factory

Destructive dust explosions have been recorded for decades across process industries. In the animal feed industry, the risk of spark ignition tends to happen during the pelletising of combustible organic materials which involves grinding and drying processes. Pellet presses are a high risk source of ignition, due to friction and high running temperatures of machinery. If sparks are created,

they can spread throughout the process machinery to silos and bins, where any accumulated or suspended feed dust is waiting fuel to start an explosion. The other significant risk is found during the drying process of

organic feed materials. Any accumulation of dust particles in the dryer when exposed to continuous levels of heat in the system, are prone to ignition. Once ignition occurs, the propagation of the flame through suspended feed dust can cause a rapid rise in pressure; the result can be an explosion of notable size. Without adequate controls and safety measures, feed dust

explosions can cause tremendous damage. Even though owners are making the effort to comply with required regulations such as ATEX and DSEAR, the execution of preventive measures is not always been correct. Many processing facilities share common problems when it comes to the installation of protective safety equipment. Here are examples of the most regularly encountered issues

when it comes to protecting against dust explosion risk. While these observations come from years of experience, always seek the help of a professional to survey your site and make the recommendations appropriate your facility’s requirements.

1. First test your dust At BS&#38;B we always recommend laboratory testing of the particular types of dust generated in your process facility. Testing is designed to identify two key performance characteristics of dust, which in turn influence explosion protection equipment design and their well as their application:


A spark detection system can counteract the risk of severe damage and harm to personnel

Even though the explosion severity of grain and feed dust is rather

low, it can still ignite at a fairly low temperature, making it a dangerous combustion risk. At the first hint of ignition, a spark detection system can counteract the risk of severe damage and harm to personnel.

3. Always protect bucket elevators Because bucket elevators have many possible ignition sources, they are a high risk piece of equipment. They are also connected to other

• The first measures maximum pressure of a dust explosion (Pmax in bar) • The second identifies the speed of the rise in explosive pressure (KSt in m/sec) The KSt will tell you how explosive your dust is. Testing can also

identify the dusts’ Minimum Ignition Temperature (MIT) and Energy (MIE) – in other words, at what temperature the dust will self-ignite through heat and static. Knowing such information about dust in relation to its process environment can help inform the user about correct precautionary measures against a potential explosion.

2. Manage hot particles or sparks Spark detection is an invaluable protective measure in feed processing and handling. By detecting and preventing sparks, embers and hot particles right at the start of the process, you prevent them from potentially reaching other equipment downstream, such as dust collectors, bins and silos.
