Drying of sludge in a greenhouse and its agronomic valorization in Uruguay
DOI:
https://doi.org/10.65628/V3.N1.18Keywords:
Circular economy, Waste management, Environmental sustainabilityAbstract
The objective of this study was to evaluate the solar drying process of sludge generated by a wastewater treatment plant at a food industry in Uruguay and to analyze its potential for agronomic valorization. Experiments were conducted during the winter period in a 3 m² greenhouse, using sludge layers 5, 10, and 15 cm thick, with weekly monitoring of their moisture content. The sludge initially had a moisture content of 83% (w.b.) and, after the drying process, reached final values of 8% (30 days), 6% (60 days), and 54% (60 days) for the 5, 10, and 15 cm layers, respectively. The dried sludge, with 8% moisture content, was analyzed for agronomic valorization, determining the concentration of heavy metals and fecal coliforms. Regarding fecal coliforms, in addition to complying with Uruguayan regulations for agricultural use, the extent to which solar drying reduced their concentration was evaluated, achieving a 96% reduction. Likewise, the heavy metal concentrations also comply with the regulations established for agricultural use. This study highlights solar drying as an economical and sustainable technology that optimizes sludge management, integrating circular economy principles and promoting its valorization as a resource for agricultural applications.
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Alonso-Suárez, R., Abal, G., Musé, P., & Siri, R. (2014). Satellite-derived solar irradiation map for Uruguay. Energy Procedia, 57, 1237–1246. https://doi.org/10.1016/j.egypro.2014.10.072
Alonso-Suárez, R. (2017). Estimación del recurso solar en Uruguay mediante imágenes satelitales. Tesis de doctorado, Facultad de Ingeniería, Universidad de la República. https://iie.fing.edu.uy/publicaciones/2017/Alo17/Alo17.pdf
An-nori, A., El Fels, L., Ezzariai, A., El Gharous, M., El Mejahed, K., & Hafidi, M. (2020). Effects of solar drying on heavy metals availability and phytotoxicity in municipal sewage sludge under semi-arid climate. Environmental Technology & Innovation, 19, 101039. https://doi.org/10.1016/j.eti.2020.101039
An-nori, A., Ezzariai, A., El Mejahed, K., El Fels, L., El Gharous, M., & Hafidi, M. (2022). Solar drying as an eco-friendly technology for sewage sludge stabilization: Assessment of micropollutant behavior, pathogen removal, and agronomic value. Frontiers in Environmental Science, 10, 814590. https://doi.org/10.3389/fenvs.2022.814590
Belloulid, M. O., Hamdi, H., Mandi, L., & Ouazzani, N. (2019). Solar drying of wastewater sludge: A case study in Marrakesh, Morocco. Environmental Technology, 40(10), 1316–1322. https://doi.org/10.1080/09593330.2017.1421713
Bose, S., & Bhattacharyya, A. K. (2008). Heavy metal accumulation in wheat plant grown in soil amended with industrial sludge. Chemosphere, 70(7), 1264–1272. https://doi.org/10.1016/j.chemosphere.2007.07.062
Bux, M., Baumann, R., Quadt, S., Pinnekamp, J., & Mühlbauer, W. (2002). Volume reduction and biological stabilization of sludge in small sewage plants by solar drying. Drying Technology, 20(4–5), 829–837. https://doi.org/10.1081/DRT-120003765
Comisión Económica para América Latina y el Caribe (CEPAL) & Gobierno del Uruguay. (2024). Estrategia Nacional de Economía Circular del Uruguay: Acciones para la transformación del sistema de producción y consumo del país (Documentos de Proyectos, LC/TS.2024/77). Santiago: CEPAL. https://www.cepal.org/es/publicaciones/80715-estrategia-nacional-economia-circular-uruguay-acciones-la-transformacion
Cota-Espericueta, A. D., & Ponce-Corral, C. (2008). Eliminación de bacterias patógenas en lodos residuales durante el secado solar. Revista Internacional de Contaminación Ambiental, 24(4), 161–170. https://www.scielo.org.mx/scielo.php?pid=S0188-49992008000400002&script=sci_arttext
Díaz, R. (1994). Cambios en el largo plazo en el carbono y nitrógeno del suelo bajo rotación de cultivos con pasturas de leguminosas. En A. Morón, W. E. Baethgen, & R. M. Díaz Rossello (Eds.), Materia orgánica en la rotación cultivo-pastura (pp. 10–12). INIA, Serie Técnica N.º 41.
DINAMA. (2017). Método 1050UY: Determinación de humedad en muestras sólidas (residuos sólidos industriales, sedimentos, suelos). En Manual de procedimientos analíticos para muestras ambientales. Versión 1. División Laboratorio Ambiental, Ministerio de Vivienda, Ordenamiento Territorial y Medio Ambiente, Uruguay. https://www.gub.uy/ministerio-ambiente/sites/ministerio-ambiente/files/documentos/publicaciones/1050UY.pdf
Freitas, V. O. de, Rola, M. C., & Liesenfeld, K. A. (2022). Diseño, construcción y evaluación de un secador solar tipo invernadero aplicado al secado de lodos. Anais Congresso Brasileiro de Energia Solar – CBENS, 1–9. https://doi.org/10.59627/cbens.2022.1133
García de Souza, M., Alliaume, F., Mancassola, V., & Dogliotti, S. (2011). Carbono orgánico y propiedades físicas del suelo en predios hortícolas del sur de Uruguay. Agrociencia Uruguay, 15(1), 70–81. https://doi.org/10.31285/AGRO.15.613
Gilsanz, J. C., Leoni, C., Schelotto, F., & Acuña, A. (2013). Uso potencial de los lodos urbanos en la producción agrícola. Agrociencia Uruguay, 17(2), 1–10. https://doi.org/10.31285/AGRO.17.457
Huber Technology. (2024). Solar dryers are in demand worldwide, even for big and medium-sized wastewater treatment plants. Huber Report. Recuperado el 5 de agosto de 2024, de https://www.hubersverige.se/en/huber-report/ablage-berichte/sludge-treatment/solar-dryers-are-in-demand-worldwide-even-for-big-and-medium-sized-wastewater-treatment-plants.html
Kürklü, A., Bilgin, S., & Özkan, B. (2003). A study on the solar energy storing rock-bed to heat a polyethylene tunnel type greenhouse. Renewable Energy, 28(5), 683–697. https://doi.org/10.1016/S0960-1481(02)00109-X
Mathioudakis, V. L., Kapagiannidis, A. G., Athanasoulia, E., Diamantis, V. I., Melidis, P., & Aivasidis, A. (2009). Extended dewatering of sewage sludge in solar drying plants. Desalination, 248(1–3), 733–739. https://doi.org/10.1016/j.desal.2009.01.011
Ministerio de Ambiente. (2021). Uruguay + Circular: Plan Nacional de Gestión de Residuos 2022–2032. https://www.gub.uy/ministerio-ambiente/sites/ministerio-ambiente/files/2025-01/URY_1BTR_2024.pdf
Ministerio de Ganadería, Agricultura y Pesca (MGAP). (2018). Resolución N.º 141/018: Requisitos técnicos para el registro de enmiendas orgánicas. Diario Oficial, 30.066. https://www.gub.uy/ministerio-ganaderia-agricultura-pesca/comunicacion/publicaciones/requisitos-tecnicos-enmiendas-organicas
Naciones Unidas. (2015). Transformar nuestro mundo: La Agenda 2030 para el Desarrollo Sostenible. https://www.un.org/sustainabledevelopment/es/
Paluszak, Z., Skowron, K., Sypuła, M., & Skowron, K. J. (2012). Microbiological evaluation of the effectiveness of sewage sludge sanitization with solar drying technology. International Journal of Photoenergy, 2012, 1–11. https://doi.org/10.1155/2012/341592
Rodríguez, D. J., Serrano, H. A., Delgado, A., Nolasco, D., & Saltiel, G. (2020). De residuo a recurso: Cambiando paradigmas para intervenciones más inteligentes para la gestión de aguas residuales en América Latina y el Caribe. Banco Mundial. https://www.bancomundial.org/es/topic/water/publication/wastewater-initiative
Sahlström, L., Aspán, A., Bagge, E., Danielsson-Tham, M.-L., & Albihn, A. (2004). Bacterial pathogen incidences in sludge from Swedish sewage treatment plants. Water Research, 38(8), 1989–1994. https://doi.org/10.1016/j.watres.2004.01.031
Salihoglu, N. K., Pinarli, V., & Salihoglu, G. (2007). Solar drying in sludge management in Turkey. Renewable Energy, 32(10), 1661–1675. https://doi.org/10.1016/j.renene.2006.08.001
Shanahan, E. F., Roiko, A., Tindale, N. W., Thomas, M. P., Walpole, R., & Kurtböke, D. İ. (2010). Evaluation of pathogen removal in a solar sludge drying facility using microbial indicators. International Journal of Environmental Research and Public Health, 7(2), 565–582. https://doi.org/10.3390/ijerph7020565
Sorrenti, A., Corsino, S. F., Traina, F., Viviani, G., & Torregrossa, M. (2022). Enhanced sewage sludge drying with a modified solar greenhouse. Clean Technologies, 4(2), 407–419. https://doi.org/10.3390/cleantechnol4020025
Vávrová, K., Králík, T., Janota, L., Šolcová, O., Čárský, M., Soukup, K., & Vítek, M. (2023). Process economy of alternative fuel production from sewage sludge and waste celluloses biomass. Energies, 16(1), 518. https://doi.org/10.3390/en16010518
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Copyright (c) 2026 Kelly Andressa Liesenfeld, Marcelo Coleto Rola, Vitória Olave de Freitas (Author)

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