The latest report in the Rapra Review Report series Plastics Waste – Feedstock recycling, Chemical Recycling and Incineration discusses the protection of the environment. Legislation is being introduced in regions such as the European Union to ensure material usage is maximized.
The recently released report examines the issues of converting Plastics Waste into energy and/or useful chemicals.
This report introduces the different waste management options. It discusses the methods available for treating mixed plastics waste and PVC-rich plastics waste. PVC can cause problems in some processes due to the chlorine content, which can cause corrosion of equipment and potentially generate hazardous gas on combustion.
The emphasis in the report is on technologies that 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. Methods have been developed including the Texaco gasification process, polymer cracking, the BASF conversion process, the Veba Combi cracking process, the 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, the Solvay Vinyloop PVC-recovery process, mechanical recycling, landfill and municipal solid waste incinerators. These processes are briefly discussed and compared to feedstock recycling as methods of disposing of plastic wastes. The commercial viability of each process is examined.
Around 400 abstracts from papers in the Rapra Polymer Library are included. Subjects covered include references to feedstock and chemical recycling, methods of energy recovery and the Vinyloop process.
For more information on the report go to Rapra’s web site at www.polymer-books.com., or send an e-mail to publications@rapra.net.