Taguchi method optimization of syngas production via pineapple waste pyrolysis using atmospheric pressure microwave plasma

Pyrolysis of the pineapple waste biomass using an atmospheric pressure microwave plasma ensures satisfactory syngas production as a renewable energy source. The pineapple waste biomass samples used in the study were crowned and peeled in dry and wet conditions. The study used Taguchi experimental methods to find the optimum parameters for the experiment. Material mass was the most influential parameter, followed by input power, carrier gas flow, and material type. Increasing input power can reduce carbon dioxide emissions while increasing the production of carbon monoxide and hydrogen. The syngas production with 800 and 1000 W power peaked for 6 and 7 min, respectively, while the plasma with 1200 power peaked at 5 min. The wet pineapple waste sample with 1200 W had the highest syngas molar ratio (H2/CO) output, the wet peel sample reached 4.18, and the wet crown sample reached 4.00. The dry sample had a lower ratio, with only 2.43 for the pineapple peel and 2.42 for the pineapple crown. The highest energy efficiency of biomass conversion is 72.59 %, achieved by a dry crown sample with 1000 W, followed by a dry crown sample with 1200 W power of 72.01 % efficiency. This finding shows that pineapple waste can be a viable feedstock in syngas production using an atmospheric pressure microwave plasma system with a rapid pyrolysis process and without catalyst added. It contributes to producing renewable energy and sustainable agricultural practices, reducing the environmental impact of conventional waste disposal methods, chemical costs, and carbon emissions to the environment.