Detailed analysis of RDF wastes and pyrolysis products

A feasible feedstock for waste-to-energy applications is refuse-derived fuel (RDF), a diverse blend composed of plastic and waste from biomass. Nevertheless, there is still a lack of quantification regarding the combined impacts of short vapor residence durations and feedstock composition in fluidized-bed decompositions. In order to close this gap, this study compares two compositionally different RDFs in a standard laboratory-sized fluidized-bed reactor under fast thermal pyrolysis conditions (550–600 °C, 2–5 s). At 550 °C, plastic-rich RDF 1 yielded a maximum liquid yield of 58 wt%, which was made up of hydrocarbon-rich oil with a high thermal value (HHV (dry) = 37.8 MJ kg −1 ) and a significant aromatic content. On the other hand, biomass-rich RDF 2 produced 52 wt%, liquid at 570 °C, with somewhat lower HHVs (35.9–39.2 MJ kg −1 ) and a higher oxygen and water concentration. Detailed characterization of the feedstock, resulting bio-oils, gases, and chars was conducted using TGA, FT-IR, NMR, GC–MS, SEM, and XRD techniques to elucidate the influence of temperature, residence time, and feedstock composition on product yield and quality. For biomass-rich RDF 2, raising the temperature from 570 °C to 600 °C decreased liquid yield while boosting olefinic entities, gaseous hydrocarbons, and suggesting increased secondary fracturing processes. Hydrocarbon, phenolic substances, and oxygenate distributions are highly dependent on RDF composition, according to product composition studies, with biomass-rich RDF tends to produce more oxygenated compounds while plastic-rich RDF tends to produce more aromatic compounds. These findings show that while minor temperature spikes (30 °C) can reroute products from liquids to gases, feedstock composition can shift liquid yield by up to ∼6 wt% and considerably impact fuel performance. In order to optimize RDF valorization in fluidized-bed systems, this work offers quantitative data that links RDF composition and fast pyrolysis parameters to product distribution.