Biogas production from different food waste using small-scale floating-drum-type anaerobic digester

Area of Science:

• Environmental Science
• Biotechnology
• Waste Management

Background:

• Food waste generation is a significant global issue.
• Anaerobic digestion offers a sustainable solution for waste valorization and disposal.
• Optimizing biogas production from diverse food waste streams is crucial for renewable energy.

Purpose of the Study:

• To compare biogas production volume and methane content from mono-anaerobic digestion of potato waste, leftover cooked food, and fish waste.
• To analyze the characteristics of different food waste substrates and cow manure inoculum.
• To evaluate the efficiency of a small-scale floating-drum digester for food waste treatment.

Main Methods:

• A small-scale floating-drum digester was operated in batch mode.
• Three food waste categories (potato, cooked food, fish) were used as feedstock with cow manure inoculum.
• Wastes were shredded, wet-fed at a 1:1 waste/water ratio, and maintained at 21°C for 10 days.
• Biogas production volume and methane content were monitored.

Main Results:

• Leftover cooked food produced the highest average cumulative biogas (261.4 L/kgTS), followed by fish waste (248.5 L/kgTS) and potato waste (137.15 L/kgTS).
• Fish waste exhibited the highest methane percentage (74%), followed by leftover cooked food (59%) and potato waste (55.8%).
• Substrate analysis included total solids, C/N ratio, and pH.

Conclusions:

• Leftover cooked food and fish waste are promising feedstocks for biogas generation via anaerobic digestion.
• The small-scale digester effectively harnessed biogas from various food waste types.
• Findings provide valuable data for optimizing food waste-to-energy systems.