How many parts can a dust collector consist of and which explosion category should it be made in?

Filtration dust collectors are one of the best solutions when it comes to dusted air cleaning in closed spaces – they are multifunctional and improve the safety of the people and of the plant. Their significant advantage is their modular structure which enables extension of an already existing installation by new modules. How many modules can a dust collector consist of and what this number depens on?

A filtration unit – the basis of dust collector structure

A single module, that is a filtration unit is in fact a self-sufficient dedusting device, which extracts the dusted, polluted air from a production hall (where the processing machines are located) – the filtration unit cleans the air and pushes the filtrated, clean air back to the production hall. The dust and dirt is caught inside of the unit, and can be easily discharged from it. The filtration units (modules) are often combined together in bigger sets which is possible thanks to the standardized (modular) structure of our own design. This way dust collectors of bigger efficiency can be bulit.

What does the number of modules in one dust collector depend on?

Theoretically, it is possible to built a dust collector that consists of a desired number of modules, however, in practice it is not neccessary – it is fair enough to select such a number of modules which is adequate for the needs of a given production plant. Which makes the answer to the question asked above very simple – the number of modules depends on the actual target efficiency of the dedusting process. And the efficiency of dust collecting is dependant on two factors:

• the number of processing machines which need to be connected to the dedusting system,
• the dust concentration in the air – depending on the processed materials

Generally speaking, the higher number of processing machines and the higher dust concentration, the bigger number of modules need to be used.

These are key issues which need to be considered when designing a dust collecting system. If, in case of insufficient number of modules, a dust collector is unable to clean the air effectively, the risk level is higher for both the people and the production venue.

Explosion proof category of a dust collector

If dusts produced during manufacture process in a given production plant are of combustible kind, they may create an explosive atmosphere – this means that the air is mixed with dust in such proportion that in case of an ignition source (e.g. a sparkle gets inside of the devices), an explosion takes place. A dust collector for a venue like that should be produced and installed according to the requirements of the ATEX directive. It means that both the structure and the protection systems of the dust collector have to be adequate for the explosion risk zone. The Atex directive enumerates three such zones:

Zone 20
It is a place where an explosive atmosphere in the form of a cloud of combustible dust in the air is present continuously, long or frequently.

Zone 21
It is a place where an explosive atmosphere in the form of a cloud of combustible dust in the air may occasionally occur during normal operation.

Zone 22
It is a place where an explosive atmosphere in the form of combustible dust in the air is not likely to occur in normal operation but, in case when it does occur, it persists for a short time only.

It is the dust kind and dust concentration that decide which zone a given production plant and its dedusting system inner parts are classified into.

Summing up …

It is clear now that dust collectors are devices that need to be selected specifically to the conditions of a given production plant. If they are not efficient enough and do not clean the air sufficiently, it may cause harmful efects for the people, the environment and the buildings. If dust collectors are too big, with overestimated parameters, their costs will be without proportion to the desired needs . As specialists in dedusting, we offer you all that is needed to selct an adequate solution.