Management of Agri-Food Waste Based on Thermochemical Processes towards a Circular Bioeconomy Concept. The Case Study of Portuguese Industry

Sustainable biomass production has significant potential for mitigating greenhouse gas emissions and is a promising alternative for the production of eco-friendly biofuels, biochemicals, and carbonaceous materials for biological, energetic, and environmental applications. Biomass from agroforestry and agricultural wastes is the richest natural carbon source and a sustainable option for woody biomass from a circular economic perspective. Portugal has several residues and by-products of agriculture, food processing, and forestry origin, and has a high availability of residual biomass. Portugal intends to reduce its dependence on energy imports and the use of fossil fuels, thereby increasing its economic performance while using biomass waste to produce high-value-added products. In this context, this review aims to explore the potential of agri-food wastes obtained from Portuguese industries via thermochemical conversion technologies as a promising sustainable alternative to woody biomass for the development of eco-friendly biofuels, biochemicals, and high-value carbonaceous materials and their applications. This strategy based on the circular bioeconomy concept can contribute to reducing the dependence on fossil fuels and minimising greenhouse gas emissions while meeting the demands of the growing population and providing a sustainable waste management solution.