Co-gasification study of biomass mixed with plastic wastes

Fluidised bed steam gasification has proven to be a possible way of converting biomass and plastic undesirable wastes into fuel gases. The addition of plastics to pine wastes decreased CO content, but increased H2 released, up to values of 50% (v/v). The highest gas yield obtained was 1.96 Nl/g daf for 98% of energy conversion, when 60% (w/w) of plastic was in the feedstock. The steam/waste mixture ratio seems to have a small effect on gas composition. Temperature is the parameter that most influenced gases composition. The rise of temperature favoured the formation of H2 and decreased the formation of hydrocarbons, tars and char. At 885°C and in presence of 40% (w/w) of plastic, conversion to char was around 2%, whilst feedstock conversion to gas was around 90%. In this paper, the effect of experimental conditions on gasification process, with the aim of enhancing the gas production and improving its composition and energetic content was analysed.