Biogas Production from Different Food Waste Using Small-Scale Floating Drum Type Anaerobic Digester

Abstract The generation of food waste poses an escalating societal challenge. Anaerobic digestion emerges as a sustainable and eco-friendly method for valorization and disposal. A small-scale floating drum-type digester was developed, operating in batch mode to harness biogas from three distinct food waste categories. Potato Waste (PW), Leftover Cooked Food (LCF), and Fish Waste (FW) were utilized as feedstock, maintained at an average temperature of 21°C for a retention time of 10 days, with cow manure serving as the inoculum source. The advances of the current work are built upon comparing biogas production volume and methane content from mono-anaerobic digestion of these various wastes. Examination of cow manure and different substrate samples offers insights into their composition, encompassing total solids, C/N ratio, and pH. Shredded raw wastes were wet-fed into the digester at a 1:1 waste/water ratio. Cumulative production of biogas and the methane fraction were monitored. The maximum cumulative biogas production per kg of waste was observed for LCF (73.5 L/kgWW), followed by FW (53 L/kgWW) and PW (37 L/kgWW). The maxium methane percentage occurred on the 7th to 8th day, with FW displaying the highest methane percentage (72%), trailed by LCF (54.6%) and PW (56%). A Statement of Novelty The novelty of this study lies in its multifaceted approach towards enhancing biogas production through mono-digestion of various organic waste materials. By focusing on the comparative analysis of these waste substrates in a controlled laboratory setting, using a simplified and efficiently designed floating drum digester, this research aims to shed light on their individual suitability for anaerobic digestion. Furthermore, the exploration extends to designing and deploying small-scale, decentralized anaerobic digestion systems tailored specifically for localized energy and waste management solutions, particularly beneficial in rural or off-grid areas. Through this integrated investigation, this study gives a comprehensive understanding of mono-digestion's contribution to biogas production and its implications for sustainable waste management practices.