Development of a Manufacturing Process of Biomass Solid Fuel with Wasted Coffee Beans and its CO₂ Assessment

Abstract

A new manufacturing process of biomass solid fuel derived from wasted coffee beans and wasted plastics was proposed in this study. A biomass sample and wasted plastics were used discharged from the certain coffee beans processing factory. At the biomass proportion of 60wt% the calorific value was 29,750 kJ/kg and corresponded to sub bituminous coal. The contents of water, ash and chlorine were 5.08wt%, 4.00wt% and 0.14wt%, respectively and these values satisfied the acceptable standard of RPF in a papermaking company. In the CO₂ assessment, the amount of discharged CO₂ of biomass solid fuel was calculated by fixing the functional unit and the calculated data were compared with the amount of discharged CO₂ of coal for fuel. When biomass and wasted plastics are mixed at the mixture ratio of 60 to 40 and is manufactured by 1 ton/hour, CO₂ is generated at the amount of 0.108 tons/hour. Concerning transportation, the distance between the place where wastes are generated and the manufacturing place of biomass solid fuel was fixed to be 200 km. Consequently CO₂ of 0.0523 tons is generated in the raw material transportation. The combustion of this material must emit CO₂ of 0.412 tons. As the final results, it was found that CO₂ of about 0.999 tons can be reduced comparing combustion of coal for power generation when 1 ton of biomass solid fuel is manufactured and combusted.