Mechanical recycling of plastic from waste of electrical and electronic equipment

Abstract

The European Union aims to increase the recycling rate of plastics. This means recy-cling evenmoreimpure and mixed plastic fractions that have previously ended up in incineration or landfill. Energy is recovered from waste incineration but is not counted for recycling. The aim is to reduce the amount of waste that ends up in landfills. This means that the recycled plastic must be of high quality in order to be re-used, or suitable uses must be devised for low-quality recycled plastic. This can open new business opportunities.Electrical and electronic waste (WEEE) is problematic for recycling due to its mixed nature. It contains several materials,and the life cycles of the devices vary in length. There are several problems and abuses associated with recycling WEEE. The aim of this study was to investigate the recycling of WEEE plasticwith simple mechanical equipment and to find out whether a useful recycledmaterial is obtained.Thismasterthesis examines the recycling of plastic separated from electricaland electronic waste. Literature review focusesonlegislation, challenges and possible uses of recycled material. The main emphasis is on mechanical recycling, but other methods are also considered. In the context of mechanical recycling, the different stages and economic aspects of the process are examined.The challenge of WEEE plastic recycling is the many grades, additives and differences in the life cycle of the equipment. In the experimental part of the work, the mechanical recycling of plastics separated from electrical and electronic waste on a laboratory scale was investigated.The plastics were cleaned with a washer and a hydrocyclone. Fractions were obtained which were granulated and injection moulded.The mechanical and physical properties of recycled plastics were examined from the prepared samples. Based on the experimental study, the properties of the recycled material were weaker than those of the virgin material. The biggest problem is impurities such as different plastic grades and miscellaneous additives. The recycled material could be used as a filler among virgin plasticbased onthis study. However, as the legislation tightens, the recycling rate must be increased and separately collected waste must not be sent to incineration in Finland, so it would be good to study other recycling methods or bettercleaning of the material.