Waste management of flame retardants in electronic plastics
In most plastics produced for mass consumer electronic products, such as PCs or TVs, flame retardants are incorporated as additives during compounding. These materials hinder plastics from burning and usually include organic halogen derivatives that are potentially hazardous chemicals according to occupational safety and health organisation reports. Nevertheless, there are currently no suitable cost-efficient techniques for the disposal of these specialised materials in an environmentally sound manner. In response, the proposed technology uses an innovative process for highly effective waste management of flame retardant materials contained in electrical and electronic equipment. Without using organic solvents, a combined method of carbon dioxide and water at supercritical conditions allows extraction and further degradation or oxidisation of extracts to minerals. Moreover, the method is also applicable for the treatment of wastes containing halogenated organics, such as those found in many chemical or pharmaceutical industries. Several components were built, including, a thin-film extractor, a counter-flow supercritical water and a continuous flow microwave reactor for treating industrial waste waters. These components and other achievements, such as an on-line measurement tool based on near infrared spectroscopy were the result of extensive research. Additionally, valuable research on the relation between key operating parameters and process brought further improvements in process concepts by employing suitable modeling and simulation techniques. Prior to disposal, waste management options include the ability to reduce, reuse and recycle in that hierarchical order of importance. The rapid technical advancements in the field of electrical and electronic equipment have resulted in an ever-increasing number of obsolete equipment. Since reducing consumption of such apparatuses or reusing them seems inevitable, the last alternative is recycling. Towards this aim, exploitation of the project results may instigate new scientific work for research and technical progress in these industries.
