Characterization of SRF from MBT plants: Influence of the input waste and of the processing technologies

Abstract Mechanical and biological treatments are the widespread treatments of mixed waste and organic waste in order to enable recovering recyclable materials from MSW. However, a large portion of mixed waste ends up as rejects, which can provide a remarkable energy content. Rejects can therefore become a solid recovered fuel (SRF) for incineration or co-incineration plants that meet the classification and specification requirements laid down in standard CEN/TS 15359 (2012). In this work, different flows of reject have been studied and identified, and different rejects have been characterized. The most important differences exist between rejects from the stages of recovery of recyclable materials and rejects from the stages of compost/bio-stabilized matter refinement. Rejects are composed mainly of combustible material, with low S, C and Hg contents, although rejects from the material recovery stage have a higher chlorine content than the others, due to their higher plastics content. Nevertheless, rejects from the material recovery stage have the most favourable SRF class code. Therefore, to take advantage of the fuel contained in the SRF it is necessary to examine the different reject flows from MSW treatment plants separately in order to improve the quality of SRF obtained from rejects.