RT info:eu-repo/semantics/article T1 Liquid fertilizer production from organic waste by conventional and microwave-assisted extraction technologies: Techno-economic and environmental assessment A1 Fernández Delgado, Marina A1 Amo Mateos, Esther del A1 Lucas Yagüe, Susana A1 García Cubero, María Teresa A1 Coca Sanz, Mónica K1 Waste compost K1 Gestión de residuos K1 Nutrient recovery K1 Recuperación de nutrientes K1 Organic fertilizers K1 Abono orgánico K1 Sustainability K1 Sostenibilidad AB The use of mineral fertilizers in agriculture has significantly increased to support the growing global food demand. Organic fertilizers are produced from renewable waste materials to overcome the drawbacks of inorganic fertilizers. The development of novel production processes of organic fertilizers entails a significant advance towards the circular economy that reincorporates waste materials into the production cycle. In this work, the economic and environmental feasibility of an industrial plant with a treatment capacity of 300 kg/h of organic waste for the production of liquid fertilizers has been performed. Two extraction technologies (conventional and microwave) and two solvents (water and alkaline) have been compared to select the most sustainable and profitable scenario for scaling-up. The extraction process consists of 2 steps: extraction followed by a concentration stage (necessary only if water extraction is applied). The resolution of the mass balances shows that the fertilizer production under alkaline conditions is ten times higher than for water-based extraction. The economic analysis demonstrated that the total investment cost of microwave technology (>3.5 M€) is three times higher compared to the conventional extraction technology (<1.5 M€), mainly due to the higher complexity of the equipment. These facts directly impact the minimum selling price, because the fertilizers obtained by conventional extraction with alkaline solvent would have a lower selling price (about 1 €/L). As for environmental assessment, the indicators show that the environmental impact produced by water-based extraction is higher than alkaline-solvent extraction, mainly due to the necessity of a concentration stage of the liquid extract to meet the requirements of European regulations. In view of the results obtained in the economic and environmental evaluation, it could be concluded that the most favourable scenario for scaling up the production of liquid fertilizers from organic waste is the conventional extraction under alkaline conditions. PB Elsevier SN 0048-9697 YR 2021 FD 2021 LK https://uvadoc.uva.es/handle/10324/49072 UL https://uvadoc.uva.es/handle/10324/49072 LA eng NO Science of The Total Environment, 2022, vol. 806, n. 4, 150904 NO Producción Científica DS UVaDOC RD 28-mar-2024