VALORIZZAZIONE DEI PNEUMATICI FUORI USO (PFU) ATTRAVERSO IL RECUPERO E RICICLAGGIO PER LA PRODUZIONE DI PRODOTTI INNOVATIVI

The aim of the current research activity is to develop, through suitable forms of re-use and recovery, scrap pneumatic tyres (SPT) in order to manufacture technical innovative products with low environmental impact. The following sectors in particular have been extensively studied: bitumen modified with SPT; sound-proofing panels for the construction industry; synthetic grass for football / rugby fields. Furthermore, the LCA (Life Cycle Assessment) method has been applied in order to evaluate the life cycle of the materials produced from SPT recovery, performed by the firm Ambra Ambiente (Cotignola di Ravenna). Regarding modified bitumen, various mixtures have been prepared, obtained by adding in various percentages powder derived from SPT. Specific laboratory tests have since allowed us to define the product from a chemical, physical and mechanical viewpoint before it is put to use as a road surface. Further laboratory tests have been performed directly upon the road surface itself as to verify its compliance to the relevant laws in effect, and therefore the final work test can be performed. Another important application of SPT regards the study and production of innovative soundproofing material, which is jet applied. Instead of the rigid panels usually used, this particular mixture is infact applied to the surface in a semi-liquid state which solidifies within 48 hours. In such a setting numerous mixtures, with differing percentages of SPT, have been tested that could ensure the soundproofing capacity as set by current laws once put to use. For this reason there have been performed numerous mechanical and acoustic tests in the laboratory and in situ on material that had been applied with the jet technique directly in various apartments. All the acoustic values recorded have found to be beneath the legal limits, which confirms that the material so produced could have important applications in the construction industry. The last application of SPT performed in the present research is its use in the production of synthetic grass for football / rugby fields. The highly constrictive regulation in this area, approved by the Lega Nazionale Dilettanti (LND), has imposed a very precise study of material loaded with SPT derivatives, both from a chemical viewpoint and from that of mechanical performance of the system as a whole. And even in this case it was possible to certify said material and reach product testing. The last part of the research was dedicated to the application of the LCA (Life Cycle Assessment) method for the evaluation the life cycle of the materials produced from SPT recovery, as performed by the firm Ambra Ambiente (Cotignola di Ravenna). Particularly through the use of dedicated software (SimaPro 6.0) it was possible to confirm that the re-use/recovery activity of SPT has overall less impact compared to waste-dumps disposal , which in any case is currently no longer possible due to the entering into effect the Legislative Decree 36/2003. It can therefore be stated that the various applications usable by the aforementioned sectors confirm that SPT is a resource to be valued and that the SPT-derived products studied in this Doctorate show performances that confirm to laws currently in effect. In short, other than the environmental aspects of reduced impact and reduce use of virgin inert material, the activity of SPT-recovery certainly represents a good investment in terms of economic profit.