The treatment of tanning wastewater has always been a matter of the utmost importance within the Tuscany Leather District, because of its environmental and economical impacts.
The sustainability of the whole tanning process strictly depends on the performances of the wastewater treatment and, as a consequence of this, within the tanning district on the right bank of the river Arno, were built three different wastewater treatment plants (WWTPs):
- Santa Croce sull'Arno
- Castelfranco di Sotto
Consorzio Aquarno was the managerial company of the plant established in Santa Croce sull'Arno, the biggest in the District, but after subsequent administrative and practical reorganisations, Aquarno has become the only manager of the municipal and industrial wastewater treatment on the right bank of the river Arno.
On July 2013, Aquarno aquired the control of the plant in Fucecchio while, the one in Castelfranco di Sotto, is still operated by another company, however its discharge stream flows to Aquarno.
Santa Croce sull'Arno centralized plant, thanks to its treatment capacity of about 2.050.000 E.I. ( Equivalent Inhabitants), is one of the biggest WWTP in Europe. It covers an approximative land surface of 2km2 where 42 basins of different capacities from 100 to 15.000m3, are distributed. The WWTP provides the cleansing of both industrial and municipal wastewater incoming from three different municipalities, to do this the plant has got two different treatment sections:
- Municipal wastewater section
- Industrial wastewater section
As a consequence of great differences among qualities and quantities of the two streams, also the wastewater treatment sections are very different, with regard to dimensions and typologies of processes involved.