Impact of aeration adjustments during the declining phase on biodrying efficiency of market waste

Abstract

The fast decomposition rate and high moisture content of market waste create substantial obstacles to creating efficient waste-to-energy systems. This research investigates the effects of adjusting aeration rates (ARs) during the declining phase of biodrying on operational performance and fuel quality. The lysimeter system with negative pressure ventilation operated three different aeration strategies, which included maintaining a constant AR of 0.6 m³/kg/day and two other configurations that lowered the AR to 0.3 m³/kg/day and 0.2 m³/kg/day during the declining phase. The research tracked essential parameters through a 7-day observation period, which included temperature fluctuations and gas releases and mass reduction, moisture content (MC), and low heating value (LHV). The AR reduction to 0.2 m³/kg/day generated the most effective results by keeping thermophilic conditions active while maintaining aerobic microbial activity. This strategy achieved the highest moisture reduction and overall mass reduction, making the final product suitable for conversion into RDF. The specific AR adjustment strategy successfully reduced thermal energy loss, demonstrating superior thermal efficiency while maintaining effective biodegradation kinetics. However, the LHV increase was found to be negligible across all treatments. This finding suggests that while the process is successful in dewatering, it is limited in its ability to significantly enhance energy density. The established methodology follows sustainable waste management guidelines and demonstrates how biodrying functions as a suitable pre-treatment method to create refuse-derived fuel in circular economy systems.