Giving Old Tires New Life

Europe's tire waste production is 3 million tons per year, and more than 65% to 70% of used tires end up in landfills. Not only are they causing environmental damage, but a loss of added value in the form of new products that recycling can generate. This is why the EU is currently funding a project called TyGRE. The purpose of TyGRE is to focus on recycling ties and turning them into gas for energy, as well as creating a number of byproducts that can be used in manufacturing.

The recycling potential of tires is tremendous: they not only possess a better heating value than biomass or coal, but they also contain a high content of volatile gasses. This makes them a great potential source of synthetic fuels (or synfuels), according to Sabrina Portofina, an Italian researcher working on TyGRE. As part of the project, she is conducting an experiment to analyze a thermal process to recuperate synthesis gas, also called syngas, and solid materials from the tire scrap.

The research project consists of two components. First, it investigates extracting the volatile gasses that form the syngas. Second, it investigates using tires to produce other materials like silicon carbide, a material used in the manufacture of ceramic materials and in electronic applications. The first stage of the experimental process set up at ENEA consists of a heat treatment of the tire scrap to over 1,000 degrees celsius. Although the heating requires energy, it will be recovered by the energy contained in the produced syngas; a mixture of mainly hydrogen, carbon monoxide and dioxide, and methane. This gas can be used as a fuel -- having a similar heating capacity to natural gas -- but also as a starter material for the production of other by-products.

Such by-products are what add the most value to the recycling process. Recycling tires to create fuels and byproducts is a promising, exciting way to get rid of scrapped tires in such a way that benefits the environment.