Browsing by Issue Date, starting with "2023-11"
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- Dados abertos no geoPortal da Energia e Geologia : Enquadramento, tipologia e gestãoPublication . Pereira, Aurete; Veiga, Arlinda; Quental, Lídia; Patinha, PedroRESUMO: O Laboratório Nacional de Energia e Geologia (LNEG) produz e disponibiliza “dados abertos” nas áreas da Energia e Geologia. A disponibilização deste tipo de dados, no seu geoPortal, vai ao encontro da política de abertura de dados promovida pela instituição no âmbito da missão que lhe está atribuída. A infraestrutura de Dados Espaciais (IDE), que suporta a informação, é também a interface com outras plataformas nacionais e internacionais, e.g. Sistema Nacional de Informação Geográfica (SNIG) ou a Infraestrutura Europeia de Dados Geológicos (EGDI). Irá também permitir a comunicação com o Portal Nacional de Dados Abertos.
- Steam reforming of biomass gasification gas for hydrogen production: From thermodynamic analysis to experimental validationPublication . Brito, João; Pinto, Filomena; Ferreira, Alexandre; Soria, M. A.; Madeira, Luís M.ABSTRACT: Biomass gasification produces syngas composed mainly of hydrogen, carbon monoxide, carbon dioxide, methane, water, and higher hydrocarbons, till C4, mainly ethane. The hydrocarbon content can be upgraded into richer hydrogen streams through the steam reforming reaction. This study assessed the steam reforming process at the thermodynamic equilibrium of five streams, with different compositions, from the gasification of three different biomass sources (Lignin, Miscanthus, and Eucalyptus). The simulations were performed on Aspen Plus V12 software using the Gibbs energy minimization method. The influence of the operating conditions on the hydrogen yield was assessed: temperature in the range of 200 to 1100 degrees C, pressures of 1 to 20 bar, and steam-to-carbon (S/C) molar ratios from 0 (only dry reforming) to 10. It was observed that operating conditions of 725 to 850 degrees C, 1 bar, and an S/C ratio of 3 enhanced the streams' hydrogen content and led to nearly complete hydrocarbon conversion (>99%). Regarding hydrogen purity, the stream obtained from the gasification of Lignin and followed by a conditioning phase (stream 5) has the highest hydrogen purity, 52.7%, and an hydrogen yield of 48.7%. In contrast, the stream obtained from the gasification of Lignin without any conditioning (stream 1) led to the greatest increase in hydrogen purity, from 19% to 51.2% and a hydrogen yield of 61.8%. Concerning coke formation, it can be mitigated for S/C molar ratios and temperatures >2 and 700 degrees C, respectively. Experimental tests with stream 1 were carried out, which show a similar trend to the simulation results, particularly at high temperatures (700-800 degrees C).
- Palynology and palynofacies studies in the lowermost Jurassic of the Lusitanian Basin (Pereiros Formation of the Silves Group), Portugal: evidence of the first transgressive episodePublication . Vilas Boas, Margarida; Pereira, Zélia; Cirilli, Simonetta; Duarte, L. V.; Sêco, Sérgio Luís Rodrigues; Fernandes, PauloABSTRACT: he Silves Group of the Lusitanian Basin in Portugal represents the initial infill of the continental rifting basins that formed during the breakup of northern Pangaea regions. Evaporites, especially halite, mark the transition from continental to marine settings and the beginning of the deposition in passive margin basins. This work presents the results of the palynostratigraphic and palynofacies analysis of two partial sections from the Pereiros Formation at the top of the Silves Group. The two sections are composed of sandstones, mudstones and dolostones interpreted as deposited in fluvial and lacustrine settings without apparent marine influence. The palynological content is diverse and wellpreserved, dating both sections to the early Hettangian (Lower Jurassic), indicated by the presence of spores Ischyosporites variegatus, Kraeuselisporites reissingeri, Porcellispora longdonensis and the pollen grains Perinopollenites elatoides and Pinuspollenites minimus. The palynological content of one of the sections (Lamas I) is noticeable by microforaminifera linings, suggesting evidence for a hitherto marine incursion at this age in the Silves Group stratigraphy. The beds that yielded the microforaminifera linings are interpreted as having been deposited in an estuarine-type setting, created by the first and short-lived marine transgressive event in the Lusitanian Basin during the early Hettangian.
- Europe’s Raw Materials Supply Chain: Front-End ConsiderationsPublication . Wittenberg, Antje; de Oliveira, Daniel Pipa Soares; Bide, Tom; Hollis, Julie; Nirgi, Siim; Žibret, Gorazd; Gautneb, Håvard; Sadeghi, Martiya; Domínguez, Rafael Navarro; Malyuk, BorisABSTRACT: Supply chains are linked for specific purpose and by something. Hence, the respective links of the chain must be hooked in the right place, sufficiently strong, and have to start somewhere. This chapter looks at the raw materials supply chain as the first link in a commodity supply, from the European Union (EU) perspective. Aspects of the raw material potential of critical or strategic mineral resources in Europe, its further exploration, and the concept of modifying factors are considered, and reporting systems of resources and reserves are described, underpinned by examples of mineral potentials in different regions of the EU. Thus, targeted exploration of raw materials, especially within the framework of national geological research, serves to support a sustainable and resilience supply chain. EU projects, such as GeoERA and Geological Service for EU, assist in shaping the tailor-made exploration programs fit for providing mineral data publicly available through EuroGeoSurveys’ European Geological Data Infrastructure. In the future, raw materials may be seen as global public goods required to address many challenges, from the climate crisis to geopolitical instability; therefore, the society could conceptualize them in a new way, from a dominant investment returns-oriented viewpoint to one linked to delivering global objectives.
- Dados abertos no geoPortal da Energia e Geologia : Enquadramento, tipologia e gestão [Comunicação oral]Publication . Pereira, Aurete; Veiga, Arlinda; Quental, Lídia; Patinha, Pedro
- A relevância da cartografia geológica para o ordenamento do território: o exemplo do Alto Douro VinhateiroPublication . Romão, José; Gomes, Maria Elisa Preto; Lourenco, José Manuel Martinho; Bento, RicardoRESUMO: Portugal foi um dos países pioneiros na elaboração de cartografia geológica do seu território, iniciando-se a sua produção em meados do séc. XIX, sendo atualmente disponibilizada em formato digital e papel pelo Laboratório Nacional de Energia e Geologia (LNEG). A conceção do modelo territorial de uma região suporta-se na caraterização e diagnóstico dos sistemas biofísico, territorial urbano e conetividade, e no produtivo de base territorial, bem como nas suas vulnerabilidades críticas. É essencial elaborar cartografia geológica a várias escalas, dado constituir um instrumento indispensável para o desenvolvimento económico, ambiental e social dos espaços territoriais. Na revisão dos Planos Diretores Municipais (PDM) de 1ª geração das autarquias do Alto Douro Vinhateiro, a cartografia geológica foi fundamental para se identificarem e representarem espacialmente, desde logo, zonas com potencial importância ecológica ou de forte suscetibilidade a riscos naturais, bem como Unidades Geomorfológicas atendendo ao parâmetro declividade. Tem desempenhado ainda um papel relevante no processo de reconhecimento e delimitação de áreas de máxima infiltração, que integram o sistema de áreas estratégicas de proteção e recarga de aquíferos no regime da Reserva Ecológica Nacional (REN), bem como na referenciação espacial dos recursos geológicos. A evolução da cartografia geológica faz-se no sentido de se constituir bancos de dados georreferenciados, interoperáveis e normalizados, recorrendo-se à integração de ferramentas de modelização (Geodesign) para representação a 3D do espaço subterrâneo. Este avanço será responsável pela melhoria significativa dos futuros Planos Diretores Municipais, em particular, nos espaços urbanos.
- Planning the Installation of Marine Renewable Energies in Portugal: a tool for decision makingPublication . Simões, Teresa; Couto, António; Estanqueiro, AnaABSTRACT: In the latest years, the European governments have developed and published the goals for their countries in terms of energy and climate as requested by the European Commission - The National Energy and Climate Plans (NECPs). In this sense, an intense activity on the planning of the installation of renewable energy systems took place in each Member State in order to meet the goals established on the NECPs. Following the recent energy crisis and the urgency to transform Europe's energy system in Europe, the NECPs are also being adapted to this situation and the installation of renewable energy systems assumed an even higher relevance. In this sense, offshore wind, due to its characteristics – high wind resource, less occupation issues and others – will play a key role in the future energy mix. This work proposed the development and application of a holistic planning methodology considering the available offshore renewable resource, restrictions to the installation of marine energy systems and economic indicators, which resulted in a techno-economic platform – MarinePlan, developed in the scope of a National funded project – OffshorePlan