The environmental and financial benefits of recovering plastics from residual municipal waste before energy recovery

A life cycle assessment was carried out to investigate the environmental benefits of removing dense plastics from household waste before burning the waste in an energy from waste (EfW) facility. Such a process was found to improve the climate change impacts of the waste management system by 75% and the non-renewable resource depletion impacts by 18%. A preliminary financial assessment suggests that the value of the plastics recovered in this way would be less than the reduction in electricity income for the EfW leading to a loss of £2-5 million per year. However, if the plastics were separated by householders for a kerbside recycling scheme, the higher price commanded by the higher-quality reclaimed plastics and lower processing costs means that overall the operation would be financially viable giving a net present value of £768 000 at a 5% rate of return. In both cases, there is a further financial benefit to the EfW operator resulting from the additional gate fees for processing waste to replace the plastics removed. Further work is required to assess the costs and effectiveness of using both kerbside collections and mechanical recovery to reduce the plastics content and carbon intensity of EfW feeds.