Together with allies in a research partnership, Swedish recycling company Stena Metall says it has developed an energy recovery method designed for its auto shredder residue (ASR) fraction.
The energy value of ASR throughout the EU can correspond to 1 million cubic meters of oil, creating significant potential in the process, says Marianne Gyllenhammar, Project Manager at Stena Metall AB.
In a news release, Stena Metall says, “Millions of tons of domestic scrap, such as scrap vehicles, are recycled every year at the European fragmenting facilities. As much as possible of the iron, nonferrous metals and other materials are recycled and processed into new raw materials. Combustible residual products such as car interiors, rubber, certain types of plastic, etc., have, however, been landfilled for many years.”
Prior energy recovery processes have run into a problem: an “admixture of certain metals and halogens can cause operational disturbances in the power and heating plants when the residual materials are recovered for energy,” according to Stena Metall.
Gyllenhammar says, though, that if “there is a well-balanced mixture of residual materials, the so-called fluff, household waste and sewage sludge, we can increase the share of fluff in the fuel mix and avoid harmful deposits on and corrosion in the combustion boiler. This is an important improvement as the solution minimizes the risk of shutdowns.”
The Stena Metall Group has eight shredding plants in Europe. The energy value of the residual materials is approximately 350 GigaWatt hours, which corresponds to 35,000 cubic meters of oil. The energy value of residual materials in all EU shredding plants is estimated to correspond to more than 1 million cubic meters of oil.
If the energy from all ASR is recovered, it will be sufficient for the heating of 400,000 small houses each year. It also solves a waste problem by helping to meet an EU directive that organic material must not be landfilled.
Full-scale trials in the project, managed by Stena Metall, were carried out at the Lidköping, Sweden, heating plant in cooperation with Metso Power, the SP Technical Research Institute of Sweden and the Chalmers University of Technology. The project will soon be presented at different international conferences, according to Stena Metall.
The Stena Metall Group collects, processes and recycles all types of scrap and is also active in the production of aluminium from recycled raw material, financial operations and international trade in steel, nonferrous metals and oil. The company operates in more than 250 locations in Sweden Norway, Denmark, Finland, Poland, Russia, Germany, the Czech Republic, Austria, Italy, Romania and the United States. More information on the company can be found at www.stenametall.com.