Setting up systems so that consumers can return obsolete products to retailers – whether or not at the time of purchase of a new product – is an effective way of diverting old products from waste streams and encouraging reuse and recycling.
Backed by legislation, such collection schemes are in place for products such as batteries and electronic goods. A Spanish project has now demonstrated that a similar approach can be effective for footwear, and that old shoes and boots can be effectively recycled into useful products.
According to the NATURALISTA project, 2.6 billion pairs of shoes and boots are sold in Europe each year, with 1.5 million tonnes of old footwear buried in landfill sites annually. Waste shoes are made up of leather, textiles and polymers – substances that degrade slowly and that, because of the way shoes are constructed, can be difficult to separate and reuse.
The project set up collection bins in El Naturalista branded stores – El Naturalista is a well-known Spanish footwear brand with origins in the La Rioja region. The old shoes collected in this way were combined with obsolete stock and old display shoes and boots. The old footwear was then processed by cutting and grinding. First it was cut down into 12mm pieces, which were sent through a conveyor system with magnets to separate the metal parts. The remaining material was then further ground down into 3-4mm granules. This was the raw material for the next stage of the project.
NATURALISTA experimented with the granules as the basis for a number of products. They were used to manufacture new shoe parts: soles, insoles and orthopaedic footwear. The granules were also tested in paving materials and in speed bumps for roads. In the speed bumps, the granules were combined with rubber, and it was found that the granules could be used in ratios of up to 66% of the total material input.
The main objective of the project was to analyse if marketable products could be produced from waste polymeric material, thus diverting waste from landfill, and reducing the need for production of new polymers. The project finished in August 2012, and has not so far published a full analysis of the environmental impacts of its processes. However, it is regarded as a success, having demonstrated public acceptance of recycled materials in shoes. More than 12,000 pairs of shoes with recycled insoles have been sold. The project promoters believe that potentially large markets for products made from recycled footwear granules can be established worldwide.
The NATURALISTA project received funding from the European Union's Competitiveness and Innovation Programme Eco-innovation initiative, and involved partners from Spain, Portugal, Poland and the Czech Republic.