Co-Processing Agricultural Residues and Wet Organic Waste Can Produce Lower-Cost Carbon-Negative Fuels and Bioplastics

Abstract

Scalable, low-cost biofuel and biochemical production can accelerate progress on the path to a more circular carbon economy and reduced dependence on crude oil. Rather than producing a single fuel product, lignocellulosic biorefineries have the potential to serve as hubs for the production of fuels, production of petrochemical replacements, and treatment of high-moisture organic waste. A detailed techno-economic analysis and life-cycle greenhouse gas assessment are developed to explore the cost and emission impacts of integrated corn stover-to-ethanol biorefineries that incorporate both codigestion of organic wastes and different strategies for utilizing biogas, including onsite energy generation, upgrading to bio-compressed natural gas (bioCNG), conversion to poly(3hydroxybutyrate) (PHB) bioplastic, and conversion to single-cell protein (SCP). We find that codigesting manure or a combination of manure and food waste alongside process wastewater can reduce the biorefinery's total costs per metric ton of CO 2 equivalent mitigated by half or more. Upgrading biogas to bioCNG is the most cost-effective climate mitigation strategy, while upgrading biogas to PHB or SCP is competitive with combusting biogas onsite.

Review on food waste valorisation for bioplastic production towards a circular economy: sustainable approaches and biodegradability assessment

“…Consideration of packaging and promoting the development of a circular economy by transforming food waste into green plastics to create recyclable containers made of bioplastic are two potential solutions to lessen the burden on the natural environment. 8 Bioplastics have been extracted from renewable sources, which are biodegradable or non-biodegradable, for the sustainable replacement of traditional plastics. The bioplastic production capacity was estimated to be 2.22 million tonnes in 2022 (ref.…”

“…Consideration of packaging and promoting the development of a circular economy by transforming food waste into green plastics to create recyclable containers made of bioplastic are two potential solutions to lessen the burden on the natural environment. 8…”