Study of the co-pyrolysis of biomass and plastic wastes

This work aimed to study the recovery of two types of waste by the process of pyrolysis. The obtained results show that the adding of a plastic mix improves the overall efficiency of the slow pyrolysis of pine. Therefore, it was possible to achieve higher liquid yields and less solid product than in the classic slow pyrolysis carbonization of biomass. The obtained liquids showed heating values similar to that of heating fuel oil. The gas products had energetic contents superior to that of producer gas, and the obtained solid fractions showed heating values higher than some coals. There were also identified some typical products of fast biomass pyrolysis used as raw material in several industries. The effects of experimental conditions in product yield and composition were also studied. The parameters that showed higher influence were (with its increase): reaction time on gas product composition (increase of the alkane content) and on liquid composition (increase in aromatics content); reaction temperature on product yield (decrease of liquid yield with increase of solids and gases) and on gas product composition (increase in alkane content); initial pressure on liquid composition (increase in the aromatics content) and mainly the pine content of the initial mixture on products yield (increase of gas and solid yield with a decrease in liquids) and on the gas product composition (favouring CO and CO₂ formation).