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Dust extraction systems can extend equipment life and reduce product cross-contamination, yet traditional cleaning systems require costly facility downtime. But, as Dustcheck outlines, new online systems are emerging
The handling and transportation of mineral products is often associated with the creation of dust emissions, usually as a result of air turbulence caused by the sudden transfer of material.
The conditions for the generation of dust are varied: the product itself can be in dust form or contain an element of dust present in its composition; a solid or granular product can create dust via attrition or agitation due to handling methods; and dust can be created as a by-product of machining operations.
The resulting emissions are undesirable and need to be controlled for a number of reasons, including personnel safety, cross-contamination of products, risk to equipment performance, and compliance with ATEX regulations (the two European Directives for controlling explosive atmospheres). Emissions can be controlled through dust extraction systems.
Dust extraction systems are selected to handle a given air volume flow rate, which is mainly dependent on the type of dust source generator and the design of hood or enclosure selected to ensure good capture.
In order to obtain the air volume flow an air mover (a fan) is often used. These air movers need to overcome the resistance associated with the collection system components; the majority of these resistances remain constant, however the resistance due to the media does not. Media resistance can range from 0.3 mbar to 15 mbar and is quite often the largest individual resistance value, where it will vary between these values over the lifetime of the media.
Unless some form of control is used to alter the performance of the air mover, and depending on the air mover's characteristics, this increase in media resistance will reduce the air volume flow rate leading to reduced collection efficiency. It is important to control the rate of increase in resistance to the minimum.
Dust extraction systems
Most providers of dust extraction solutions focus heavily on the types of media they can offer, and while this is a major component in the dust extraction system it needs to be matched closely with the method of cleaning - since it is the cleaning system that...