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The textile industry generates millions of tons of waste annually, making this sector one of the most polluting in the world. The objective of this research was to study the energy potential of three industrial textile wastes of vegetable and animal origin: CW (card waste), SFW (short fibre waste) and W (wool), using conventional and flash pyrolysis at 500 °C and 750 °C. CW and SFW thermogravimetric profiles were very different from W. In general, the bio-oil yield was higher in the conventional and in the low-temperature flash pyrolysis (up to 55 %). The gas obtained by flash pyrolysis at 750 °C has higher flue gas content and lower CO2 content so their high heating value (HHV) is higher (up to 15.34 MJ/kg). Bio-oils obtained by flash pyrolysis at high temperature stood out for their higher HHV (>30 MJ/kg), with the highest value (34.15 MJ/kg) obtained from SFW waste. Both low temperature flash pyrolysis and conventional pyrolysis produce bio-oils that contain aromatic (35–48 %) and non-aromatic (18–34 %) organic compounds. Additionally, they have high levels of phenols and benzenes. High-temperature flash pyrolysis bio-oils are mainly composed of polycyclic aromatic hydrocarbons. The textile samples are suitable for an energetic valorisation, highlighting the best SWF behaviour.

Residual biomass is a valuable and growing by-product, but often underutilized. This research aims to investigate the possible strategies for the energetic valorisation of agri-food industry wastes: grape seed and chestnut shell. Pyrolysis thermal process was the selected for this work. Applied to biomass, pyrolysis is a promising method for the simultaneous production of biochar, bio-oil, and gas. Two different pyrolysis processes were conducted: conventional pyrolysis at 750 °C and flash pyrolysis at 750 °C and 850 °C. Flash pyrolysis yielded superior product properties compared to conventional pyrolysis. The gas obtained through flash pyrolysis presented a four-fold higher high heating value due to increased CH4 and H2 content. Bio-oil contains over 90% of polycyclic aromatic hydrocarbons, and calorific value reached up to 32 MJ kg−1 for grape seed, which is 7% more than bioethanol HHV. Biochar can be used both as fuel or as activated carbon precursor due to its high carbon content (91%). Calorific value of chestnut shell biochar (32.7 MJ kg−1), comparable to mineral coals, increased by 72% with respect to the value of this untreated raw material. This work approved the potential of flash pyrolysis as a method to process biomass wastes in a renewable energy scenario.