http://repositorio.lnec.pt:8080/jspui/handle/123456789/50 DHA 2026-10-26T10:00:03Z http://repositorio.lnec.pt:8080/jspui/handle/123456789/1020099 Full-scale multipurpose ozonation in urban wastewater with strong textile input: removal of colour, micropollutants, pathogens and antimicrobial resistance indicators Campinas, M.; Vaz-Moreira, I.; Viegas, R.M. C.; Mesquita, E.; Ribeiro, D.; Ruivo, A.; Soares, J.; Paíga, P.; Delerue-Matos, C.; Faria, G.; Silva, C.; Costa, C.; Manaia, C; Rosa, M. J. Understanding multipurpose ozonation performance under realistic and variable wastewater conditions is critical for investment decisions under the revised EU Urban Wastewater Treatment Directive (EU-UWWTD). As most studies focuses on single treatment objectives or homogeneous municipal effluents, integrated evaluations are particularly needed for industry-influenced wastewaters, where ozone reactivity and process efficiency can differ markedly. This study aims to provide a holistic assessment of full-scale ozonation by simultaneously investigating the responses of chemical and biological contaminants, as well as microbial community dynamics, variable ozone doses applied primarily for textile colour control. To our knowledge, this is one of the first integrated full-scale studies of ozonation in a strongly textile-influenced urban WWTP (51% of total inflow). Ozonation performance was assessed through three full-scale experimental campaigns, each evaluating three ozone doses in the range of 0.4–1.0 mg O₃/mg TOC. The study evaluated colour removal, micropollutant abatement, pathogen and antimicrobial resistance (AMR) indicators reduction, by-product formation, acute toxicity and surrogate parameters for process monitoring. Ozonation had little effect on bulk organic parameters but achieved 50–84% colour removal and near-complete elimination of terrestrial humic-like fluorescence. High organic matter content and colour constrained ozone exposure, shifting micropollutant abatement towards predominantly •OH-driven oxidation. Nevertheless, ozonation alone achieved ≥80% removal of the monitored micropollutants at ozone doses ≥0.65 mg O₃/mg C, indicating its major contribution towards EU-UWWTD compliance targets. Somatic coliphages and bacteria log-reductions ranged from 0.9 to >2.3 and from 0.2 to 1.2, respectively. Acute toxicity was reduced, whereas AMR gene abundance showed limited sensitivity to ozone dose. Post-treatment microbial regrowth was observed, particularly at higher ozone doses, including bacterial groups carrying resistance genes, suggesting a selection-like process. Operational surrogate indicators (A254, A436, colour-scan and PARAFAC components) were identified/validated to support process monitoring and EU-UWWTD implementation in complex wastewater matrices. 2026-07-01T00:00:00Z http://repositorio.lnec.pt:8080/jspui/handle/123456789/1020097 Diagnosis of residual flow drivers in estuaries with the densimetric tidal Froude number Khosravi, M.; Fortunato, A. B.; Lopez-Ruiz, A.; Valle-Levinson, A.; Garel, E. Diagnosis of Residual Flow Drivers in Estuaries with the Densimetric Tidal Froude Number Residual circulation in estuaries drives salt intrusion, material transport, and ecosystem functioning. Yet the ability to diagnose its dominant forcing mechanism remains a challenge. While previous studies suggest that the densimetric tidal Froude number (Frt) may distinguish tidal from baroclinic forcing, its reliability across varying estuarine conditions and spatial scales requires systematic evaluation. This study investigates whether Frt can reliably diagnose the dominant drivers of residual circulation in estuaries by using a suite of process-oriented numerical simulations in an idealized estuary–shelf system with Gaussian cross-channel bathymetry. The model configuration spans a wide parameter space, including variations in tidal amplitude, channel depth, lateral slope, and river discharge. Residual circulation regimes are diagnosed using the ratio between the barotropic and baroclinic terms of the tidally averaged, axial momentum equation obtained from the model outputs, together with the transverse structure of residual flows, allowing direct comparison with Frt predictions. This study demonstrates, for the first time, that Frt can reliably diagnose the dominant driver of residual circulation when the density length scale is defined over the shortest feasible axial distances. Crucially, the results show that the skill of Frt is highly sensitive to this spatial scale: its performance deteriorates when the density gradient is computed over lengths that extend into regions with heterogeneous forcing. Across all simulations, Frt functions as a robust bulk indicator of tide-dominated, density-dominated, and near-balanced regimes only when the density scale is restricted to zones where the axial salinity gradient is approximately constant. Such zones consistently occupy the seaward side of the peak salinity gradient. Within this region, Frt emerges as a reliable diagnostic tool and offers practical value for field applications that require identifying the prevailing residual-flow driver. Tidally driven circulation is characterized by relatively high Frt values (0.53 ± 0.31), density-driven circulation by low values (−0.23 ± 0.16), and near-balanced regimes occupy a narrow transitional interval (0.12 ± 0.14) in which neither process exerts clear dominance. Future research may evaluate how these thresholds vary with the estuarine configuration. 2026-07-01T00:00:00Z http://repositorio.lnec.pt:8080/jspui/handle/123456789/1020018 Parecer do Plano de Atividades do LNEC, I.P. PARA 2026 Leitão, T. E.; Serra, C. Este relatório apresenta o parecer sobre o Plano de Atividades do LNEC para 2026, visando avaliar a sua exequibilidade, rigor e coerência com a estratégia institucional. Através de uma análise nos contributos das Comissões Científicas Departamentais (CCD), o documento emite um parecer favorável, condicionado à revisão de alguns aspetos. 2026-04-01T00:00:00Z http://repositorio.lnec.pt:8080/jspui/handle/123456789/1019979 Activated carbon adsorption in water treatment - an expanding application Rosa, M. J.; Mestre, A.S.; Silva, C.; Mesquita, E.; Campinas, M.; Carvalho, A. P.; Viegas, R.M. C. Population growth, water scarcity, and climate change are driving the need for enhanced control of organic micropollutants and contaminants of emerging concern (CECs) in the urban water cycle1. Activated carbon adsorption is considered a best available technology for removing these challenging contaminants, such as pharmaceuticals, pesticides, and cyanotoxins, from both drinking water and treated wastewater. This communication focuses on the application of powdered activated carbon (PAC) and granular activated carbon (GAC) in drinking water and urban wastewater treatment (DWT, UWWT). Several key projects have supported the research and demonstration of these advanced materials and treatment technologies for DWT (LIFE Hymemb, FCT EMPOWER+, CYTED-Recircula), UWWT (LIFE Impetus, LIFE ReFitting), non-potable water reuse (FP7 TRUST) and direct potable water reuse (H2020 B-WaterSmart). 2026-06-01T00:00:00Z