How to decrease the environmental impact of tannery finishing plants

Mattia Dal Ceredo

In tanneries, the spray finishing plants are mainly composed of the paint booth and the drying tunnel where the leathers are dried.
The environmental impact is usually very high, since during the processing several airbrushes function simultaneously in order to cover the entire surface of the leather with the paint.
Using a high number of airbrushes results in a considerable production of overspray.
The term “overspray” refers to the paint that is sprayed but which is not deposited on the surface to be covered. By its nature, overspray does not benefit the coating process in any manner.
Overspray is also a cost inasmuch as it results in an increase in the quantity of material that must be disposed of, it increases the load on the filters, it dirties the booth and it increases the emissions into the atmosphere; its reduction can therefore represent a saving.
Furthermore, the overspray which is deposited on the parts already painted negatively influences the quality of the coating process, reducing the shine of the surface and contributing to the “orange peel” effect.

The overspray ends up in the purification systems which have the purpose of reducing fumes by means of the use of water.
The fumes expelled must respect the limits laid down by law.

How can the environmental impact be cut down, and the quality of the coating be increased?
With the S1 system.
In fact S1 stabilises the air temperature of the nebulisation and optimises the application of the paint. The compressed air used to initially atomise the paint is filtered and purified, and successively heated to then be re-issued into the nebulisation circuit.
Thanks to a decrease in the viscosity of the paint, the atomisation pressure can be reduced. Several benefits will be obtained, including a reduction in the environmental impact, a reduction in the quantity of paint used, and a higher quality finish inasmuch as the chemical product is sprayed more evenly onto the leather.