Publisher's Synopsis
Protection of our environment is now a global priority and legislation is being introduced in regions such as the European Union to ensure that material usage is maximised. Much of the development work has been pioneered in Germany which introduced very strict recycling laws. This report examines the issue of converting Plastics Waste into energy and/or useful chemicals. Polymers are generally derived from fossil fuels which are being gradually depleted. Much plastic material is discarded as waste, such as packaging and end-of-life vehicle components. It is essential that we find means to preserve fossil fuels and to reuse materials in some form. Life cycle analysis is being performed on the different methods of disposing of waste plastics to discover the most environmentally friendly methods. mechanical recycling is often discussed but it is limited by the need to separate and clean used plastics prior to recycling. This report introduces the different waste management options. It discusses the methods available for treating mixed plastics waste and PVC-rich plastics waste. can cause corrosion of equipment and potentially generate hazardous gas on combustion. The emphasis in this report is on technologies which are already being used or assessed for use on a commercial scale. Comparisons are made between the different types of recycling currently available in terms of life cycle assessment and environmental impact. The EU draft directive on Packaging waste includes definitions of the types of recycling. Chemical recycling implies a change of the chemical structure of the material, but in such a way that the resulting chemicals can be used to produce the original material again. Such processes include monomer recover. There are few commercial techniques available which accomplish this, one outstanding example is nylon carpet recycling. Feedstock recycling is discussed extensively in this review. It is defined as a change in the chemical structure of the material, where the resulting chemicals are used for another purpose than producing the original material. polymer cracking, the BASF conversion process, the Veba Combi cracking process, BSL incineration process, the Akzo Nobel steam gasification process, the Linde gasification process, the NKT pyrolysis process and pressurised fixed bed gasification from SVZ. Typical feedstocks generated include synthesis gas, containing mainly CO and H2. By-products such as chlorides are generally sold on for other processes and slag can be used in applications such as building. Energy released during these processes is generally used or recovered. Alternatives to feedstock recycling include cement kilns (energy recovery), the Solvay Vinyloop PVC-recovery process, mechanical recycling, landfill and municipal solid waste incinerators (energy recovery). These processes are briefly discussed and compared to feedstock recycling as methods of disposing of plastics wastes. The commercial viability of each process is examined. This report is accompanied by around 400 abstracts from papers in the Rapra Polymer Library. also methods of energy recovery and the Vinyloop process.
