6.1 The tanning process requires inputs such as water, energy and chemicals and produces outputs mainly represented by water discharges, waste and emissions into the atmosphere.

Raw to tanned leather

The first stages of the tanning process require water, subsequently purified at a consortium plant serving the entire tanning district. The treatments envisaged break down pollutants such as COD, suspended solids, chlorides, sulphates, organic nitrogen and chromium III, reducing them to non-hazardous values for the environment. This treatment leads to the production of sludge currently disposed of in landfills. This step also originates by-products such as scraps, fur and skin trimmings that are sent to recovery, becoming a component of fertilisers and biostimulants thanks to their appreciable protein content.

Tanned to crust leather

The wastewater from the dyeing operations is sent to the purification plant, where it is adequately treated. Mechanical drying operations require modest amounts of electrical and thermal energy.

From crust leather to finished leather

The intermediate and final ennobling operations give rise to powders and volatile organic substances (SOV), conveyed to filters, blast chillers and post-combustion systems, which guarantee compliance with the legal limits.

The environmental aspects related to tanning are governed by an articulated legislation, which is implemented in specific and articulated environmental authorisations issued by the Public Administration in which the numerous environmental requirements that the company must comply with to exercise its activity are reported.

The regulatory complexity and, above all, the desire to guarantee an effective and structured management of environmental aspects have led Gruppo Mastrotto to equip itself with an Environmental Management System (EMS) that establishes a company policy, precise assignments of responsibilities, both at group level and for each individual plant, an environmental improvement programme and adequate monitoring indicators.

In addition to its EMS, Gruppo Mastrotto implements an even more stringent environmental monitoring plan for the 3 sites that have obtained the Integrated Environmental Authorisation (AIA), namely the sites of Via Quarta Strada, 7 and Via della Concia, 156 in Arzignano and the site of Santa Croce sull’Arno, adopting the best available technologies in the sector:

Reuse Of Water At Certain Stages Of The Production Process

timely monitoring of water discharges elimination of solventbased chemicals differentiation of the waste produced, start to recover them and reduction of packaging waste adoption of advanced technologies in some spraying (finishing) plants for the saving of chemicals and the reduction of atmospheric emissions reduction of VOC5 emissions into the atmosphere by means of a post-combustion plant, with a reduction of more than 90% of emissions

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