Valorization of Food Waste into Hydrochar

Abstract

Abstract The dwindling fossil fuels that are being unsustainably exploited are soon going to finish. One of the major reasons for the exploitation of fossil fuels is their use as an energy source in industries. While we are nearing the end of our reserves, we are also running out of our carbon budget projected to remain within the 1.5 . While the world battles with the unprecedented patterns of climate change it is important to look for alternate clean and renewable energy sources. Biomass as a source of renewable energy only contributes 0.9% of the total primary energy consumption by source. If we increase the percentage of renewable energy harvested from biomass we can reduce stress from fossil fuels and decrease carbon emissions due to the carbon neutrality of biomass. Hydrothermal carbonization is an attractive technology due to its several advantages like compatibility with varied moisture content, the lack of need for pretreatment and it results in hydrochar which is a carbon dense energy-rich material. Three fruits, apple, banana and orange were selected for the hydrothermal carbonization. Microwave-assisted hydrothermal carbonization resulted in a lower mass yield of hydrochar. The six samples that were analyzed banana peel hydrochar had an energy densification ratio of less than 1. In the critical analysis, it was later concluded that owing to the lesser lignin content than the other two fruits, banana peel resulted in a lower energy yield. The effects of mixed biomass were also investigated in the research. The combination of biomasses resulted in a higher mass yield, however, lower calorific values.