Fast pyrolysis and steam gasification of pellets prepared from olive oil mill residues

This paper examines the fast pyrolysis coupled with the steam gasification of agropellets prepared from the olive oil industries by-products via Macro-thermogravimetry. Three pellets samples were prepared from exhausted olive mill solid waste, impregnated olive mill wastewater/exhausted olive mill solid waste and impregnated olive mill wastewater/pine sawdust. The behavior of the three pellets during the fast pyrolysis and the char gasification stages were generally comparable despite some small differences in the conversion rates or char yields. The gasification of impregnated olive mill wastewater/exhausted olive mill solid waste pellets was selected as a promising route for their valorization and the reduction of the pollution impacts of olive mill wastewater. The impregnated olive mill wastewater/exhausted olive mill solid waste pellets pyrolysis rate was affected significantly by the temperature in the range of 750°C–950 °C. The mean char gasification rate was linearly dependent on temperature and steam molar fractions in the respective ranges of 750°C–950 °C and 10%–30% of steam concentration. The provided data on the fast pyrolysis and char gasification of the formulated impregnated olive mill wastewater/exhausted olive mill solid waste pellets constitute new set of experimental data that can serve for the design of gasifiers working with such kind of wastes.