An MCDM approach for selection of a biomass fuel for a natural convection dryer based on thermo-economic-environmental analysis

Abstract Efficient selection of optimal biomass fuel for the developed natural convection dryers is essential for enhanced drying performance, ensuring environmental and economic viability. This research applies a Multi-Criteria Decision-Making (MCDM) approach based on the Analytical Hierarchy Process (AHP) and the Technique for Order of Preference by Similarity to an Ideal Solution (TOPSIS) to analyze thermo-economic-environmental factors for fuel selection. By preparing four different biomass pellets and evaluating these based on heat generation, environmental impact, and cost-effectiveness, the study aims to determine the best fuel for the dryer. The results indicate that the drying system can sustain higher temperatures for extended periods, and exhibit excellent energy and exergy efficiency. The drying system experiences reduced exergy losses of 28.82 to 31.98 W. The financial assessment reveals a payback period of 0.34 years for the dryer. The exhaust gas contains 1703–1928 ppm of CO, 32–44 ppm of NO and 5.3–7.2 ppm of SO 2 . The MCDM approach identifies the 80:10:10 mixture of sawdust, charcoal, and burnt engine oil as more effective blend of biomass. The study concludes that using biomass pellets with appropriate mixing ratios as fuel in the developed natural convection dryer significantly enhances its drying performance and sustainability.