When looking to protect your equipment against a dust explosion, it is critical that you know the Kst value of your material. Kst, is the dust deflagration index, and it measures the relative explosion severity compared to other dusts. This is a relative index, however, and any material with a Kst value greater than zero is considered to be at risk of an explosion. In fact, sugar has a relatively low Kst value, but was the fuel for for a massive explosion in 2008 that claimed the lives of 14 workers1.
Dust explosions present a real problem for manufacturing facilities. Plants that handle and process dry bulk materials are especially at risk because of the amount of dust that is created during normal handling and processing. The threat of dust explosions is made worse by the fact that they are not limited to a single industry. Any plant in any industry that handles dry materials is at risk including:
Food Production
Metal Processing
Wood Products
Chemical Manufacturing
Rubber and Plastics
Coal-fired Power Plants
Learn how dust explosions happen, and why they cause so much damage. Also learn some of the steps that are being taken to help prevent dust explosions, including some of the potential new legislation.
Air Classification can separate materials across particle sizes that are too fine to screen, and can improve the efficiency of mills.
When are air classifiers used?
Air Classifiers are normally used when the particle size that needs to be separated is too fine to screen. The air classified product can be the granular Coarse discharge with very little Fines/Dust or the Fines discharge with very little Coarse/Grit. Air Classifiers eliminate the blinding and breakage issues associated with screens.
How dry does the feed need to be?
In order to effectively remove fine powders, the surface moisture of the feed must be very low, less than 1 – 2% is best, but some fines can be removed even at 2.5-3%.
