VENTILATION SYSTEMS

CENTRAL VENTILATION AND DEDUSTING SYSTEMS

Centralized systems are the most commonly used method to capture and remove airborne pollutants from the working environment.
In many industrial processes can develop emissions of dust, fumes, gases, toxic or flammable vapours of any kind. The employer must take appropriate measures to prevent or reduce as far as possible their development and spread in the working environment.

Contaminating atmospheres, in addition to human risk, are highly undesirable in industrial production as dust, fumes and vapours can cause numerous inconveniences on exposed machinery and cause damage to the products.

Localised aspiration has the task of capturing the pollutants as close as possible to the point of production of the pollutants (source), before they are breathed by workers or spread into the working environment, to channel them and cut them down before entering the atmosphere in order to reduce concentrations to values compatible with the protection of the environment.

A correct design of the suction systems is, of course, the one able to achieve the best control of the atmosphere with the minimum consumption of air and energy.

Schematic diagram of vacuum dedusting plant

MAIN COMPONENTS OF A VENTILATION AND DEDUSTING SYSTEM:

System of collection: extractor hood (closed, receiving, catching), mobile arm, and suction vent

Ducting of suction pipe: connecting pipe between the various collection points and the filtration system. It is very important to size it correctly to ensure that the polluted are correctly picked up and conveyed to the air purifier (filter). A correct sizing and installation, allows to avoid the eventual deposit of polluted particles inside it and to reduce to a minimum the losses of load (greater efficiency of the plant)

The filtration system is the device that allows to separate/filter the pollutant aspirated from gaseous flow. Depending on the characteristics of the pollutants, different filtration/purification systems are adopted which can also be combined together to maximise filtration efficiency. The main filtration systems are:

Electro-fan: is the machine for handling polluted air inside the intake system, through the creation of a negative pressure (intake) inside the ducts that connect it to the various intake points. It is driven by a motor powered by electric energy, which is then converted into the energy of pressure and kinetic energy of the air current moved.

Channelling of expulsion: the purified air flow shall be expelled from the outside in such a way as to dilute as far as possible the remaining pollutant. Re-entry into the working environment is not permitted in the case of toxic pollutants.