1. Department of Chemical Engineering, UPC, Avenue Diagonal 647, H-4, 08028 Barcelona, Enviros Spain S.L., Passeig de Rubí 29-31, 08197 Valldoreix, Barcelona, Spain, and Enresa-Enviros Environmental Science and Waste Management, UPC, Jordi Girona 1-3, B2, 08034 Barcelona, Spain