Simultaneous Maximization of Char Yield and Volatility of Oil from Biomass Pyrolysis

This study proposes continuous biomass pyrolysis featuring internal recycling of a heavier portion of bio-oil (HBO) that evaporates, leaving solid residue when reheated. The recycling of HBO enables the selective production of light bio-oil (LBO) that is free from residue after evaporation, and also the maximization of the char yield. The performance of the proposed pyrolysis has been examined C (CZ) in series. The HBO recycling increases the char yield from the pyrolysis of pine sawdust from 0.25 to 0.36 kg/kg of dry feedstock while producing LBO, in which the organic compounds have carbon numbers no greater than 13. Such a large increase in the char yield is caused by two different events. HBO is captured by the parent biomass in CZ and undergoes self-charring and/or co-experimentally by employing an originally designed simulator of a vapor–solid countercurrent moving bed reactor, which provides the zone for pyrolysis at 120–550 °C (PZ) and the zone for capture of HBO by the parent biomass at 120 °carbonization in PZ. The vapor of HBO is decomposed over the surface of pyrolyzing solid (char) in PZ and then converted into a portion of char, LBO, and/or gas.