Employment of conventional and flash pyrolysis for biomass wastes from the textile industry with sustainable prospects

Abstract

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.