4161 research outputs found
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Li-ion Battery Recycling: A Summary Review
No full textABSTRACT: A short review of battery recycling technologies is presented. Main components and materials of battery cells, modules and packs are identified, highlighting their compositions and contents. Main component of packs is aluminium, followed by the cathode materials, anode materials, copper and polymers. Safe discharge of the spent batteries is mandatory, and the subsequent dismantling allows separation and valorisation of the aluminium casings, electronic components, polymers and steel. The resulting cells or modules are pretreated by shearing and drying, and the solvent and evolving gases shall be safely treated and disposed. Physical separation operations, including secondary shredding, sieving, gravity separation, among others, are applied to separate the Al, Cu and polymer fragments from the electrode powders (black mass). Metallurgical processing, by hydro or pyrometallurgy, allows further recovery of the metals in pure forms, which are then sent back to the market. Nowadays, several hydrometallurgical processes are being introduced, allowing high recovery yields of the most important metals such as lithium, cobalt, nickel and manganese. By this way, a more sustainable management of the resources can be achieved.Innovation Pact “NGS – New Generation Storage” (C644936001-00000045) by the “NGS” consortium, cofinanced by NextGeneration EU, through the Incentive System – “Agendas for Business Innovation”, within the Recovery and Resilience Plan (PRR)
Functional alginate aerogels as green catalytic platform for CO₂-to-syngas conversion [Resumo]
No full textDeformação em ortognaisses peralcalinos em zonas de cisalhamento de escala orogénica: cartografia geológica e estrutural na região de Arronches (Zona de Cisalhamento Tomar-Badajoz-Córdoba, Zona de Ossa-Morena)
No full textABSTRACT: The lithological units in the Arronches region (included within the Arronches tectonic unit, Tomar-Badajoz-Córdoba Shear Zone, northernmost Ossa-Morena Zone) and in particular the peralkaline orthogneisses therein, have been the target for petrological, geochemical and structural studies in order to constrain its petrogenesis and tectono-metamorphic contextualization within the broader regional geology. Two detailed geological-structural maps of the Arronches region (from the Arronches village and the Fialha area), as well as the structural analysis allow the description of two mylonitic high strain fabrics found in different peralkaline orthogneiss bodies (the dominantly Arronches-type S fabric and the dominantly Fialha-type S-L fabric), which provide better insights about the internal architecture of the Tomar-Badajoz-Córdoba Shear Zone.RESUMO: As unidades litológicas na região de Arronches (incluídas na unidade tectónica de Arronches, Zona de Cisalhamento Tomar-Badajoz-Córdoba, extremo norte da Zona de Ossa-Morena) e em particular os ortognaisses peralcalinos, têm sido alvo de estudos de petrologia, geoquímica e geologia estrutural, para constranger a petrogénese e contextualização tectono-metamórficas para a geologia regional. Dois mapas geológico-estruturais detalhados da região de Arronches (da vila de Arronches e da área da Fialha), bem como uma análise estrutural permitiram a descrição de dois tipos de texturas miloníticas encontradas em diferentes corpos de ortognaisses (o fabric S dominante no tipo Arronches e o fabric S-L dominante no tipo Fialha) o que fornece uma visão mais detalhada sobre a arquitectura interna da Zona de Cisalhamento Tomar-Badajoz-Córdoba
Mineralogical characterization of the iron ore from the Cabeço de Mua and Carvalhosa (Moncorvo) deposits
No full textRESUMO: tecnologia e das infraestruturas de um país. Com o intuito de melhor conhecer os minérios de ferro de Portugal, especificamente dos jazigos de Cabeço da Mua e da Carvalhosa, foram efetuados estudos petrográficos, metalográficos e de microscopia eletrónica de varrimento com espetroscopia por dispersão de energias (MEV-EDE). Os minerais principais identificados foram quartzo, hematite e goetite, havendo algumas ocorrências de fosfatos disseminados, magnetite e fosfatos detríticos. O estudo MEVEDE destes minerais permitiu identificar os seus constituintes, tendo sido possível encontrar elementos terras raras nos fosfatos, nomeadamente em monazites. Para uma melhor caracterização dos minérios deveriam ser feitos estudos mais aprofundados, visto tratarem-se de amostras muito ricas e heterogéneas.ABSTRACT: Iron is a material of high importance for the development of technologies and infrastructures of a country. In order to better characterize iron ore deposits of Portugal, specifically the Cabeço de Mua and the Carvalhosa deposits, petrographic, metallographic and scanning electron microscope (SEM-EDS) studies were conducted. Quartz, hematite and goethite were identified as the main minerals present, although disseminated phosphates, magnetite and detrital phosphates also occur. Thanks to the SEM-EDS analysis, it was possible to identify the components of each mineral phase, with rare earth elements being found in the phosphates, specifically in monazites. Due to the samples’ richness
and heterogeneity, further detailed studies are required to improve the characterization of the ore
Environmental assessment of the Jequitinhonha river basin, in the Northeast portion of the State of Minas Gerais, Brazil
No full textRESUMO: A bacia hidrográfica do rio Jequitinhonha destaca-se pela heterogeneidade. O objetivo deste trabalho é apresentar uma avaliação ambiental da qualidade dos sedimentos e da disponibilidade das águas superficiais através de índices ambientais de uma porção da bacia localizada no Nordeste do Estado de Minas Gerais. A partir de dados de estações de monitoramento foram analisadas séries históricas de chuvas, vazões fluviais e sedimentos em suspensão de 1990 a 2021 e integrados dados de uso e ocupação do solo dos anos de 2000, 2007 e 2011. As concentrações de EPTs foram determinadas por ICP-OES e ICP-MS. O cálculo dos índices ambientais demonstrou que as maiores concentrações ocorrem em áreas onde as litologias são naturalmente ricas em EPTs. Contudo, os dados temporais mostraram que desde 2007, o Médio-Baixo Jequitinhonha passou a sofrer reduções na vazão fluvial e na carga de sedimentos em suspensão causadas pela instalação da Central Hidrelétrica de Irapé.ABSTRACT: The Jequitinhonha river basin stands out for its heterogeneity. The objective of this research is to present an environmental assessment of the quality of sediments and the availability of surface waters through environmental indices for a portion of the basin located in the Northeast of the State of Minas Gerais. Using data from monitoring
stations, historical series of rainfall, river flows and suspended sediments from 1990 to 2021 and evaluating land use and occupation data from the years 2000, 2007 and 2011. Obtaining concentrations of EPTs by ICP-OES and ICP-MS. The calculation of environmental indices demonstrated that the highest concentrations occur in areas where lithologies are naturally rich in EPTs. However, temporal data showed that since 2007, the Middle-Lower Jequitinhonha started to suffer reductions in river flow and suspended sediment load caused by the installation of the Irapé Hydroelectric Plant
3D and Earth observation viewers as a source of promotion and expansion of geological knowledge
No full textRESUMO: Os visualizadores 3D e de observação da Terra no geoPortal de Energia e Geologia proporcionam o acesso a dados multifonte para suportar, melhorar e expandir o conhecimento geológico. Estas plataformas expõem novos dados e disponibilizam novas funcionalidades para uma melhor interação adaptada aos requisitos dos utilizadores. Estes incluem a componente altimétrica, índices de deteção remota, perfis espectrais e comparação com materiais padrão, análise multitemporal e deteção de alterações, para uma visão sinótica da caracterização geológica e evolução atualizada. O resultado geral permite uma melhor compreensão da superfície e subsuperfície da Terra combinando dados de deteção remota, geologia e formas de relevo, promovendo e expandindo assim o conhecimento geológico.ABSTRACT: The 3D and Earth observation viewers within geoportal of Energy and Geology provide access to multisource data to support, enhance and expand geological knowledge. These platforms expose new data and allow several new functionalities for improved interaction tailored to the stakeholders needs. These include the elevation component, remote sensing indices, spectral profiles and comparison with standard set of materials, multitemporal analysis and change detection, for a fast overview of geological characterization and updated surface evolution. The overall
result allows a better understanding of the Earth´s surface and subsurface combining remote sensing data, geology, and landforms, thus promoting and expanding geological knowledge.Projeto GPGE2020 e Projeto GeoON - Informação Geológica e Mineira Online (POCI-05-5762-FSE-000426)
Benchmarking commercially available value-added fractions with potential for production via microalgae-based biorefineries: is it worth it?
No full textABSTRACT: The urgent need to mitigate climate change requires finding sustainable and efficient alternatives to fossil fuel-based materials. Biosequestration by microalgae has been suggested as a potential method for climate change mitigation due to its environmentally friendly nature and ability to produce high-value compounds. However, the large-scale application of microalgal biorefineries faces significant challenges, particularly in the harvest and processing stages, which are often costly and energy-intensive. This study aims to benchmark value-added fractions that can be produced via microalgae-based biorefineries against their commercially available counterparts. A systematic review was conducted using the Web of Science™ database to identify current commercial sources of proteins, lipids, polyunsaturated fatty acids and pigments, this study identified key sectors and applications for each fraction, as well as potential market competitors. The results highlight substantial cost differences across production systems, with traditional agricultural sources demonstrating lower CAPEX but greater environmental challenges. Meanwhile, microalgal systems, although associated with higher CAPEX, offer advantages such as reduced land and water dependency, potentially leading to long-term economic resilience and environmental sustainability. By pinpointing research trends, key sectors and optimization opportunities, this work offers valuable insights into the profitability and competitiveness of microalgal systems, providing a benchmark for future optimization efforts. The novelty of this research lies in its comprehensive comparison of microalgae-based and traditional production systems, establishing a clear benchmark for microalgal production and suggesting focus areas for enhancement.N/
Piggery wastewater treatment by solar photo-Fenton coupled with microalgae production
No full textABSTRACT: Pig farming generates highly polluted wastewater that requires effective treatment to minimize environmental damage. Microalgae can recover nutrients from piggery wastewater (PWW), but excessive nutrient and turbidity levels inhibit their growth. Solar photo-Fenton (PF) offer a sustainable and cost-effective pretreatment to allow microalgal growth for further PWW treatment. This study optimized the concentrations of PF reagents to minimise water and nutrient inputs while maintaining microalgae-based treatment efficiency. PF trials were conducted in pilot-scale raceway ponds under solar radiation, testing different concentrations of FeSO4 (4.48 and 8.95 mM) and H2O2 (77, 154, and 309 mM). Following PF, Tetradesmus obliquus was used in a biological treatment of PWW to recover the remaining nutrients. PF achieved high removal efficiencies for turbidity (97.6-99.5 %), total organic carbon (59.2-77.1 %), and chemical oxygen demand (83.8-94.7 %), but ammonium was not significantly removed. Phosphorus was almost completely removed through iron precipitation during neutralisation. Lowering the H2O2 concentration from 309 to 77 mM did not compromise removal efficiency but reducing FeSO4 below 8.95 mM negatively affected the process. Consequently, 8.95 mM FeSO4 and 77 mM H2O2 were selected for microalgae production. The pretreated PWW could be recycled at least once for microalgal production, without nutrient supplementation, improving biomass productivity and PWW treatment, especially targeting ammonium. Phosphorus supplementation, however, did not significantly boost biomass productivity or treatment efficiency. Moreover, the iron sludge generated from PF pretreatment contained enough NPK to be repurposed as an organic fertilizer boosting sustainable agricultural practices. These findings encourage further investigation of this emerging combined technology towards wastewater treatment at large-scale.info:eu-repo/semantics/publishedVersio
Ordenamento do Território e Desenvolvimento Sustentável da Indústria Extractiva
No full textRESUMO: Os conceitos de organização e desenvolvimento territorial enquanto função do estado tiveram origem na comunicação do ministro francês Claudius Petit, “Pur un plan national d’aménagement du territoire”, em 1950 (in C. ALVERGNE et P. MUSSO, 2003) em que este defendeu uma repartição da população francesa em função dos recursos naturais e das diferentes actividades económicas, procurando assegurar um maior equilíbrio entre cidade/campo e litoral/interior, ao mesmo tempo que a preservação do meio ambiente não seria esquecida. Esta procura de racionalidade no uso do território tem sofrido diversas evoluções consoante é abordado como um objectivo a atingir ou como um conjunto de processos instrumentais integrados para a organização do espaço físico. Hoje em dia o Ordenamento do Território anda a par, de modo indissociável, com os conceitos e políticas de desenvolvimento sustentável na procura das melhores soluções que possam conduzir a uma eficaz e rentável ocupação do território sem degradar as condições ambientais nem comprometer o seu uso futuro. O espaço territorial é, em si mesmo, um recurso.info:eu-repo/semantics/publishedVersio
A indústria ibérica de rochas ornamentais e minerais industriais
No full textABSTRACT: After more than two millennia of mining history, Spain and Portugal together produce approximately one billion tons of rocks and industrial minerals each year. In Spain and Portugal, the industry of ornamental rocks and industrial minerals has developed significantly in recent years. The demand for construction and ornamental materials has increased, and both countries have emerged as world leaders in the production of marble and other ornamental products. Despite environmental and competitive challenges, the industry remains profitable and continues to grow steadily.RESUMO: Após mais de dois milénios de história da mineração, Espanha e Portugal produzem juntos cerca de mil milhões de toneladas de rochas e minerais industriais a cada ano. Em Espanha e Portugal, a indústria das rochas ornamentais e minerais industriais desenvolveu-se significativamente nos últimos anos. A procura por materiais de construção e ornamentais aumentou e ambos os países emergiram como líderes mundiais na produção de mármore e outros produtos ornamentais. Apesar dos desafios ambientais e competitivos, a indústria continua lucrativa e em constante crescimento