Influence of temperature and residence time in the pyrolysis of woody biomass waste in a continuous screw reactor

Both the peak temperature and the exposition time at peak temperature have an impact in the pyrolysis fractions yields and composition, however it is at 1173 K where the bigger changes occur both in pyrolysis products yield and composition. In all cases the solids obtained (charcoal) fulfill the requirements to perform as metallurgical reducers. The higher the peak temperature the greater the charcoal quality but the lower the pyrolysis solid yield since secondary pyrolysis reactions consume charcoal. The pyrolysis gases obtained are valuable products rich in CO (22-35 vol%) and hydrogen (35-50 vol%); on the contrary, the pyrolysis liquids obtained are mainly worthless products composed of water and some aromatic compounds (e.g. naphthalene, fluorene & antrhacene).