Strategic recycling and valorisation of waste plastics for improving the circular economy

Mixed post-customer plastic waste (MPW) is one of the world’s largest waste stream challenges. In January 2018, the UK government pledged that all ‘avoidable plastic waste’ will be eradicated by 2042. Traditional methods for processing MPW (incineration, landfill) are no longer sustainable. Hence, the UK’s recycling industry is under pressure to procure innovative processes to recycle MPW, with a view to improving the circular economy. Urbanisation is also accelerating, placing pressure on the cement/aggregate industries to meet the demand for construction materials. However, cement production is energy intensive and produces 10% of the world’s atmospheric CO2 emissions. Hence, there is a need to develop low carbon construction materials that utilise industrial wastes and improve the circular economy. MPW has technical prospects for re-use in road surfacing and as a construction material but has yet to be investigated in detail. Research at Teesside University has revealed that sewage sludge can be pyrolysed to produce char and gas co-products, resulting in an 85% reduction in waste volume. Chars from MPW pyrolysis have encouraging prospects for applications within the engineering and energy sectors. There are also prospects for harnessing pyrolysis gas co-products as an energy source. The aims of this project are: 1) valorise MPW to demonstrate it adds value to industrial waste derived energy systems and improves the circular economy; 2) assess the technical prospects of recycling MPW char with aggregates to form new durable construction materials; 3) determine the potential for harnessing heat and gas co-products from pyrolysis as a renewable energy source.