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- LNEG obrigado a aceitar as certificações dos biocombustíveis reconhecidas pela UEPublication . Gírio, FranciscoRESUMO: Recentemente, notícias vieram a público sobre possível fraude na origem de biocombustíveis usados na Europa e em Portugal. A Associação ZERO veio mesmo sublinhar que, apesar de Portugal ter assumido o compromisso de abandonar o uso de biocombustíveis à base de óleo de palma, inscrito na Lei de Bases do Clima e no Orçamento do Estado para 2022, a medida nunca saiu do papel. Por outro lado, os produtores nacionais de biocombustíveis, através das suas organizações, Associação Portuguesa de Produtores de Biocombustíveis (APPB) e Associação Bioenergia Avançada (ABA), referem mesmo que as autoridades nacionais não controlam as possíveis fraudes na origem, em particular as matérias-primas que chegam à Europa que são resíduos da indústria de palma, caso do efluente de éster metílico de óleo de palma (POME) e dos cachos vazios de frutos de palma. E alegam que existe uma diferenciação de tratamento entre produtores nacionais/europeus e terceiros (fora da UE), com um escrutínio mais apertado aos produtores nacionais. Em súmula, todos pedem uma atuação urgente do Estado português. Entre as medidas propostas, estão a revisão do modelo europeu de certificação, passando o controlo para entidades públicas, a criação de um sistema transparente de rastreabilidade e informação ao consumidor, bem como o reforço do combate à fraude através de uma estrutura europeia dedicada. Acresce que estas queixas das empresas não ocorrem apenas em Portugal, sendo agora o momento para nos debruçarmos com factos sobre a realidade atual. Relativamente a eventuais fraudes nos biocombustíveis, alguns países europeus — casos da Bélgica, Holanda e Irlanda — fizeram chegar ao Conselho Europeu alegações de fraudes com biocombustíveis provenientes da Ásia, que, até ao momento, não foram consubstanciadas por estes países nem comprovadas. Apenas a Alemanha apresentou na Comissão Europeia (CE), em 2023, uma queixa formal sobre fraude na importação de biodiesel da China. Após mais de um ano e meio de investigações pela CE, esta acabou de encerrar o caso, informando que não foi possível comprovar evidências de fraude, embora admita que identificou fraquezas na legislação europeia de confirmação da sustentabilidade dos biocombustíveis, principalmente nas matérias residuais produzidas na origem, e anunciou medidas de curto e médio prazo para tornar o sistema europeu mais robusto à fraude. Em Portugal, a entidade que supervisiona o sistema de certificação na produção ou importação de biocombustíveis é o Laboratório Nacional de Energia e Geologia, através da Entidade Coordenadora do Cumprimento dos Critérios de Sustentabilidade (LNEG/ECS). O LNEG/ECS atua apenas a montante na cadeia de valor, estabelecendo e verificando a aplicação da Diretiva 2018/2001 (RED II) desde a matéria-prima utilizada até à produção ou importação do biocombustível. Decorrente desse trabalho, o LNEG/ECS informa mensalmente a ENSE E.P.E., para cada operador económico, sobre quais os lotes de biocombustíveis classificados como sustentáveis e se tem direito a um Título de Biocombustível (TdB) simples ou duplo.
- Descarbonizar micro/mini-redes através da complementaridade da produção solar fotovoltaica e eólicaPublication . Couto, António; Cardoso, João P.; Simões, Teresa; Estanqueiro, Ana; Stevanato, N.; Mereu, R.RESUMO: Este trabalho apresenta uma metodologia para determinar a capacidade instalada ótima de fontes de energia renováveis variáveis no tempo, numa mini-rede selecionada, e avaliar o potencial destas tecnologias para satisfazer o consumo de eletricidade, permitindo reduzir a dependência de geradores alimentados por combustíveis fósseis. A capacidade ótima é identificada com base na exploração estratégica da sinergia eólica e solar fotovoltaica (FV) para atender à procura de eletricidade, neste caso, para substituir a produção com geradores a diesel. Para este efeito, neste trabalho, explora-se o uso de diferentes ângulos de azimute e inclinação dos sistemas solares fotovoltaicos fixos (convencionais e bifaciais), bem como sistemas com seguimento para criar um portfólio de geração ideal. Os resultados preliminares obtidos destacam que é necessário diversificar a orientação dos painéis solares e explorar a energia eólica para evitar vários períodos com excesso de produção e, consequentemente, corte de geração. Apesar de ser necessário continuar a desenvolver este trabalho, os resultados mostram que o uso dos geradores a diesel pode ser significativamente reduzido, especialmente durante o período diurno.
- A Infraestrutura INIESC no Contexto da EU-SOLARIS: Actividades e Perspectivas FuturasPublication . Horta, Pedro; Canavarro, Diogo; Cardoso, João; Azevedo, Pedro; Martinez, Diego
- Estimativa do Potencial Técnico da Energia Solar Térmica no Setor dos Edifícios e na Indústria em PortugalPublication . Cardoso, João; Facão, Jorge
- Systematic and Bibliometric Review of Biomethane Production from Biomass-Based Residues: Technologies, Economics and Environmental ImpactPublication . Tiago, Gonçalo A. O.; Rodrigo, Naresh P. B.; Lourinho, Gonçalo; Lopes, Tiago; Gírio, FranciscoABSTRACT: Fossil fuels drive global warming, necessitating renewable alternatives such as biomethane (or renewable natural gas). Biomethane, primarily produced through anaerobic digestion (AD), offers a cleaner energy solution but is limited by the slow AD process. Biomass gasification followed by syngas methanation has emerged as a faster alternative. This review examines advancements in these processes over the last decade (2015–2024), focusing on techno-economic and life cycle assessment (LCA) studies. Techno-economic analyses reveal that biomethane production costs are influenced by several factors, including process complexity, feedstock type and the scale of production. Smaller gasification units tend to exhibit higher capital costs (CAPEX) per MW capacity, while feedstock choice and process efficiency play significant roles in determining overall production costs. LCA studies highlight higher impacts for gasification and methanation due to energy demands and associated emissions. However, integrating renewable hydrogen production through electrolysis, along with innovations such as sorption-enhanced gasification (SEG), can enhance overall system efficiency and reduce environmental impacts. This review critically evaluates the technical and economic challenges, along with the opportunities for optimizing biomethane production, and discusses the potential for these technologies to contribute to sustainable bioenergy solutions in the transition to a low-carbon economy.
- Chemical and Mineralogical Characterization ofWaste from Abandoned Copper and Manganese Mines in the Iberian Pyrite Belt, Portugal: A First Step Towards the Waste-to-Value Recycling ProcessPublication . de Oliveira, Daniel Pipa Soares; Silva, Teresa; Morais, Igor; Fernandes, JoãoABSTRACT: This study examines the chemical and mineralogical composition of waste materials from abandoned copper and manganese mines in the Iberian Pyrite Belt, Portugal, as a first step toward their potential recycling for critical and strategic raw materials (CRM and SRM). Using portable X-ray fluorescence (pXRF) and other analytical techniques, this research highlights the presence of valuable elements, including copper, manganese, and rare earth elements, in concentrations significantly above their crustal abundance. The findings underscore the dual potential of these wastes: as sources of secondary raw materials and for mitigating environmental hazards such as acid mine drainage (AMD). Recovered materials include chalcopyrite, pyrolusite, and rhodochrosite, with critical elements like cobalt, lithium, and tungsten identified. pXRF proved to be a reliable, cost effective tool for rapid field and laboratory analyses, demonstrating high precision and good correlation with standard laboratory methods. The study emphasizes the importance of characterizing historical mining waste to support a circular economy, reduce reliance on foreign material imports, and address environmental challenges. This approach aligns with the European Union’s Critical Raw Materials Act, promoting sustainable resource use and the recovery of strategic resources from historical mining sites.
- Simulation of Surface Segregation in Nanoparticles of Pt-Pd AlloysPublication . Correia, Jose B.; Sá, AnaABSTRACT: Platinum (Pt) and palladium (Pd) are crucial in hydrogen energy technologies, especially in fuel cells, due to their high catalytic activity and chemical stability. Pt-Pd nanoparticles, produced through various methods, enhance catalytic performance based on their size, shape, and composition. These nanocatalysts excel in direct methanol fuel cells (DMFCs) and direct ethanol fuel cells (DEFCs) by promoting alcohol oxidation and reducing CO poisoning. Pt-Pd catalysts are also being explored for their oxygen reduction reaction (ORR) on the cathodic side of fuel cells, showing higher activity and stability than pure platinum. Molecular dynamics (MD) simulations have been conducted to understand the structural and surface energy effects of PdPt nanoparticles, revealing phase separation and chemical ordering, which are critical for optimizing these catalysts. Pd migration to the surface layer in Pt-Pd alloys minimizes the overall potential energy through the formation of Pd surface monolayers and Pt-Pd bonds, leading to a lower surface energy for intermediate compositions compared to that of the pure elements. The potential energy, calculated from MD simulations, increases with a decreasing particle size due to surface creation, indicating higher reactivity for smaller particles. A general contraction of the average distance to the nearest neighbour atoms was determined for the top surface layers within the nanoparticles. This research highlights the significant impact of Pd segregation on the structural and surface energy properties of Pt-Pd nanoparticles. The formation of Pd monolayers and the resulting core-shell structures influence the catalytic activity and stability of these nanoparticles, with smaller particles exhibiting higher surface energy and reactivity. These findings provide insights into the design and optimization of Pt-Pd nanocatalysts for various applications.
- Exploring Marine Biomineralization on the Al-Mg Alloy as a Natural Process for In Situ LDH Growth to Improve Corrosion ResistancePublication . Marques, Maria João; Mercier, Dimitri; Seyeux, Antoine; Zanna, Sandrine; Tenailleau, Christophe; Duployer, Benjamin; Jeannin, Marc; Marcus, Philippe; Basséguy; BASSEGUY, RegineABSTRACT: This study provides a detailed characterization of the AA5083 aluminum alloy, surface, and interface over 6 months of immersion in seawater, employing techniques such as SEM/EDX, GIXRD, mu-Raman and XPS. The purpose was to evaluate the evolution of the biomineralization process that occurs on the Al-Mg alloy. By investigating the specific conditions that favor the in situ growth of layered double hydroxide (LDH) during seawater immersion as a result of biomineralization, this research provides insights into marine biomineralization, highlighting its potential as an innovative and sustainable strategy for corrosion protection.
- Optimizing bacterial nanocellulose production from eucalyptus bark: A circular approach to wastewater management and resource recoveryPublication . Rodrigues, Ana Cristina; Martins, Daniela; Duarte, Maria Salomé; Marques, Susana; Gama, Miguel; Dourado, Fernando; Carvalho, Ricardo; Cavaleiro, AnaABSTRACT: The production cost of bacterial nanocellulose (BNC) is a major limitation to its widespread use. However, this limitation can be addressed by using alternative low-cost substrates and high-yield strains. Agro-industrial wastederived substrates offer a cost-effective and sustainable solution, but their high organic load often requires additional downstream wastewater treatments. Here, we optimized static BNC production using eucalyptus bark hydrolysate (EBH) as a low-cost carbon source and proposed a circular approach for wastewater management. Optimization was performed using response surface methodology - central composite design. The optimized EBH medium yielded a 39.7-fold increase compared to standard medium, with a maximum BNC production of 8.29 f 0.21 g/L. Fermentation wastewater only (WaF) and combined with BNC washing streams (WaW) revealed high levels of organic matter, namely chemical oxygen demand (COD) of 159.0 f 2.0 and 41.1 f 0.3 g/L, and volatile solids (VS) of 99.5 f 0.9 and 26.3 f 0.2 g/L, respectively, requiring treatment before disposal. A sequential anaerobic-aerobic digestion was investigated for wastewater treatment and valorisation. Anaerobic digestion proved to be effective in treating the wastewater: methanization percentages over 87 % were achieved, and methane productions of 486 f 2 and 544 f 30 L/kg VS were obtained from WaF and WaW, respectively. Subsequent aerobic treatment was unsuccessful in further reducing COD levels (approximately 1.5 g/L). Notably, treated wastewater was recycled into the production process up to 45 % without affecting the BNC yield. This study provides valuable insights into the optimization of BNC production from lignocellulosic biomass and the management of wastewater streams, contributing to the development of a more sustainable and economically viable process.
- Biopolymers Derived from Forest Biomass for the Sustainable Textile IndustryPublication . Dias, J. C.; Marques, Susana; Branco, Pedro C.; Rodrigues, Thomas; Torres, Cristiana A.V.; Freitas, Filomena; Evtuguin, Dmitry; Silva, CarlaABSTRACT: In line with environmental awareness movements and social concerns, the textile industry is prioritizing sustainability in its strategic planning, product decisions, and brand initiatives. The use of non-biodegradable materials, obtained from non-renewable sources, contributes heavily to environmental pollution throughout the textile production chain. As sustainable alternatives, considerable efforts are being made to incorporate biodegradable biopolymers derived from residual biomass, with reasonable production costs, to replace or reduce the use of synthetic petrochemical-based polymers. However, the commercial deployment of these biopolymers is dependent on high biomass availability and a cost-effective supply. Residual forest biomass, with lignocellulosic composition and seasonably available at low cost, constitutes an attractive renewable resource that might be used as raw material. Thus, this review aims at carrying out a comprehensive analysis of the existing literature on the use of residual forest biomass as a source of new biomaterials for the textile industry, identifying current gaps or problems. Three specific biopolymers are considered: lignin that is recovered from forest biomass, and the bacterial biopolymers poly(hydroxyalkanoates) (PHAs) and bacterial cellulose (BC), which can be produced from sugar-rich hydrolysates derived from the polysaccharide fractions of forest biomass. Lignin, PHA, and BC can find use in textile applications, for example, to develop fibers or technical textiles, thus replacing the currently used synthetic materials. This approach will considerably contribute to improving the sustainability of the textile industry by reducing the amount of non-biodegradable materials upon disposal of textiles, reducing their environmental impact. Moreover, the integration of residual forest biomass as renewable raw material to produce advanced biomaterials for the textile industry is consistent with the principles of the circular economy and the bioeconomy and offers potential for the development of innovative materials for this industry.