1. Environmental Engineering, Dept. of Civil and Environmental Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ, UK (corresponding author).
2. Postgraduate Researcher, Dept. of Civil and Environmental Engineering and Dept. of Materials, Imperial College London, South Kensington Campus, London SW7 2AZ, UK.
3. Full Professor, Dept. of Materials, Imperial College London, South Kensington Campus, London SW7 2AZ, UK.
4. Reader in Waste Management, Dept. of Civil and Environmental Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ, UK.