Fast pyrolysis of cellulosic ethanol solid residues with high ash and lignin contents in a fluidized bed

Pyrolysis of corn stalk residue (CSR) and cassava rhizome residue (CRR) to produce bio-oil were investigated using a fluidized bed reactor. Both feedstocks possessed low volatile matters and high ash contents. The results showed that the bio-oil yield of CSR reached the highest value (25.1%) at 700 °C, while that of CRR peaked (30.6%) at 600 °C. The obtained bio-oils were separated into light fraction and heavy fraction automatically. The light fraction mainly consisted of furan compounds and carboxylic acids, while the heavy fraction mainly consisted of aromatic compounds. Due to the abundant lignin in the residues, high heating values (HHVs) of the heavy fractions reached 25.5-26.8 MJ/kg which were significantly higher than typical bio-oils.