Pyrolysis of municipal food waste: A sustainable potential approach for solid food waste management and organic crop fertilizer production

Abstract

Food waste can be converted to a useful product such as biochar as a way of recycling waste to retain nutrients in the soil, which in turn contributes to carbon sequestration and offset some greenhouse gas emissions in the struggle to achieve carbon neutrality. Mixed food waste-derived biochars (FWB1–300°C, FWB2–450°C and FWB3–600°C) were pyrolysed at 300°C, 450°C and 600°C, respectively, using an electric kiln. Tests for physiochemical parameters and germination tests were performed. It was realized that at 300°C biochars produced had high nitrogen, organic matter, bulk density, biochar yield, and longer root lengths. The results indicate that municipal food waste biochars produced at three temperatures were suitable for use as fertilizer. However, biochar produced at a moderately lower temperature is favourable for agriculture purposes, FWB1–300°C and FWB2–450°C obtained moderate pH and ash levels and so are less toxic to the growth of plants.