Sustainable management and recycling of food waste anaerobic digestate: A review

Anaerobic digestion (AD) is a widely used technology to valorise food waste for biogas production yet a considerable amount of digestate remains under-utilised. Sustainable management and recycling of the nutrientrich food waste anaerobic digestate (FWD) is highly desirable for closing resource loop and actualising circular economy. This work reviews the distinct properties of FWD and the existing treatment technologies. FWD shows great prospects as a nutrient source for microalgal cultivation and biofuel production. Emerging technologies such as thermal conversion (e.g., pyrolysis and hydrothermal treatment) of FWD into value-added products such as functionalised biochar/hydrochar with diverse applications would be attractive and warrant further research investigation. Integrated AD with subsequent valorisation facilities is highly encouraged to achieve complete utilisation of resources and reduce carbon emissions.

Automated summary

Anaerobic digestion is widely used to produce biogas from food waste, but a significant amount of nutrient-rich food waste anaerobic digestate (FWD) remains under-utilised. FWD has potential as a nutrient source for microalgal cultivation and biofuel production, and emerging technologies like thermal conversion show promise in converting FWD into value-added products like biochar/hydrochar. Integrated AD with valorisation facilities is encouraged to achieve complete resource utilisation and reduce carbon emissions.