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.

GRAPHICAL ABSTRACT

KEYWORDS:

• Biochar
• pyrolysis
• food waste
• organic fertilizer
• solid waste management

Highlights

• Increased generation of food waste due to growing population.

• Disposal of food wastes into landfills reduces landfill lifespan.

• Gases and leachate generated during landfilling, a threat to the ecosystem.

• Food waste biochar production—waste management and organic fertilizer production.

Abbreviation

FWB represents Food Waste biochar, all biochars produced from Food Waste constitute a mixture of cooked and uncooked food wastes which were dried and milled; FWB1–300°C, FWB2–450°C and FWB3–600°C; pyrolysis temperature at which production was achieved include 300°C, 450°C and 600°C, respectively.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The authors confirm that the data supporting the findings of this study are available within the article.

Additional information

Funding

The project was supported by Ghana and International Development Association and implemented by World Bank Financing Agreement Credit number 5423-GH through the Regional Water and Environmental Sanitation Centre Kumasi (RWESCK) at the Kwame Nkrumah University of Science and Technology, Kumasi.