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- Enterprise Europe Network (EEN) : Notas para a preparação de relatórios de sustentabilidade : Informação de apoio às PMEPublication . Miranda, Miguel; Catarino, Justina; Couto, António; Lopes, Fernando; Afonso, JoanaRESUMO: A Enterprise Europe Network (EEN) é uma rede de serviços que tem como objetivo ajudar as empresas ou organizações a inovar e a competir no quadro internacional. As entidades que pretendam inovar, competir e estabelecer parcerias com as suas congéneres estrangeiras ou que necessitam também de instrumentos que lhes permitam avaliar o desempenho do seu modelo de negócio podem fazê-lo através desta rede. Das diversas possibilidades disponibilizadas pela EEN destaca-se a preparação de relatórios de sustentabilidade. Os relatórios de sustentabilidade e a EEN podem estar relacionados por diferentes maneiras uma vez que esta rede visa auxiliar as empresas ou organizações a tornarem-se mais competitivas e inovadoras por via da oferta de um conjunto de serviços e informações relevantes num quadro internacional. No âmbito da Sustentabilidade, a EEN permite a disseminação, em larga escala, de informação diversa, bem como das melhores práticas relacionadas com o desenvolvimento sustentável em diferentes áreas de atuação. No quadro da divulgação de informações do modelo de negócio, os relatórios de sustentabilidade são utilizados como uma ferramenta que permite avaliar e comunicar o desempenho ambiental, social e económico de uma empresa ou organização. A EEN pode fornecer orientações e recursos que permitem apoiar estas entidades a desenvolver os seus relatórios de sustentabilidade, garantindo que as informações relevantes sejam identificadas e divulgadas de maneira adequada e assertiva. Na partilha de boas práticas, a EEN atua como uma plataforma de divulgação de boas práticas entre as entidades, de experiências na implementação de medidas sustentáveis e dos resultados alcançados, também por via dos relatórios de sustentabilidade, servindo de inspiração a outras empresas a adotarem práticas semelhantes. Na componente da sustentabilidade, a EEN pode oferecer ainda um suporte e uma orientação para todas as entidades que tenham o objetivo de se tornarem mais sustentáveis, por via da divulgação de informações sobre regulamentações ambientais, incentivos governamentais, bem como através da identificação de estratégias de economia de recursos em diferentes áreas tidas como relevantes. Os relatórios de sustentabilidade podem ser uma ferramenta muito útil na avaliação do progresso e na identificação de novas áreas de atuação ou de áreas que podem ainda ser desenvolvidas. Esta informação permite também demonstrar o compromisso e o desempenho destas entidades, tornando-as mais resilientes e, consequentemente, mais atrativas para investidores, parceiros comerciais e clientes. No quadro do acesso ao financiamento e nas oportunidades de negócios, a rede EEN permite ainda identificar oportunidades de financiamento e de negócios. Assim, os relatórios de sustentabilidade e a EEN estão estritamente interligados no sentido de que esta rede internacional pode fornecer suporte, orientação e recursos às entidades que manifestem o compromisso em promover a sustentabilidade e que, tenham ainda como objetivo, a avaliação e a comunicação do desempenho do seu modelo de negócio nas mais diferentes áreas de atuação. O presente documento congrega um conjunto de informação objectiva, estruturada e orientada e que tem como principal objetivo apoiar as entidades na preparação de relatórios de sustentabilidade. Assim, na Secção 1 são apresentados os serviços disponibilizados pela EEN, bem como identificadas as principais vantagens e a relação de proximidade que existe entre a EEN e estas entidades e a sua relação (critérios, benefícios e obrigatoriedade) com as normas e indicadores - European Sustainability Reporting Standards (ESRS). Na Secção 2 são abordados os temas relacionados com as normas europeias, o seu enquadramento, transparência, comparabilidade e gestão de desempenho, identificando os principais requisitos, objetivos e os critérios, bem como identificados os Critérios Técnicos de Avaliação e os Objetivos de Desenvolvimento Sustentável no âmbito da Taxonomia da União Europeia. Na Secção 3 é apresentada a estrutura e as principais áreas de atuação das ESRS-ESG (Environmental, Social e Governance) e sua relevância, identificados os desafios e limitações, bem como as principais estratégias de superação dos desafios. Nesta secção são ainda assinaladas algumas limitações ao atual enquadramento normativo. Na Secção 4 são apresentadas as principais conclusões.
- Effects of experimental conditions and of addition of natural minerals on syngas production from lignin by oxy-gasification: comparison of bench- and pilot scale gasificationPublication . Pinto, Filomena; Andre, Rui N.; Carolino, Carlos; Miranda, Miguel; Abelha, Pedro; Direito, Daniel; Dohrup, Jesper; Sorensen, Hanne Risbjerg; Gírio, FranciscoGasification of spent lignin pellets was used to obtain a gas suitable for energy production. Spent lignin was obtained from second-generation cellulosic ethanol demo plant using wheat straw as feedstock. Gasification of lignin did not give rise to any feeding problems, thus no significant changes were needed in the existing gasification installation. The rise of temperature and steam flow rate favoured the formation of H2, while hydrocarbons (CnHm) and tar contents decreased. The increase of equivalent ratio (ER) also decreased hydrocarbons and tar contents, but syngas higher heating value (HHV) was reduced. The use of natural minerals improved lignin gasification. The presence of dolomite led to the highest H2 and to the lowest CnHm and tar contents. Results obtained at bench-scale were confirmed at pilot-scale, as similar trends were obtained. However, as the residence time in pilot gasifier was higher, greater gas yields with higher H2 and CH4 concentrations were obtained, while tar contents decreased. After syngas hot cleaning and upgrading, the final syngas composition showed to be suitable for a wide range of applications (e.g. energy production and synthesis of chemicals), since it was substantially enriched in hydrogen, whereas tar and heavier gaseous hydrocarbons were completely destroyed.
- Potencial de integração de energia solar térmica de concentração em processos de secagem de resíduosPublication . Loureiro, David; Miranda, Miguel; Martins, António; Viegas, Sandra; Rodrigues, Hugo; Lobo, Gonzalo; Prieto, Elisabet Gonzalez; Galan, Silvia Pérez; Dias, Ivo; Mendez, Juan Orta; Perez, Manuel B. Acevedo; Mantilla, VictorRESUMO: A consciencialização dos problemas resultantes das atividades económicas relacionadas com a gestão de resíduos nas regiões transfronteiriças da Andaluzia-Algarve-Alentejo (AAA), conduziu ao desenvolvimento do projeto SECASOL. Este projeto de cooperação visa a integração de energia solar térmica de concentração (ESTC) nos processos de secagem de lamas de depuração de águas residuais (ETAR) e de resíduos sólidos urbanos (RSU). Foi avaliada a integração da energia solar de concentração em processos de secagem, através da identificação das principais soluções técnicas e tipologias de secagem de resíduos e caracterização dos processos tecnológicos com influência nos requisitos de valorização do produto final. Através da estimativa dos valores anuais para GHI e DNI nas principais instalações de tratamento de RSU e águas residuais do Algarve e Andaluzia, utilizou-se um modelo simplificado para estimativa do potencial de utilização da energia solar em dois processos de secagem de interesse – materiais CDR de RSU e lamas de depuração de ETAR- em termos de quantidade de matéria processada por unidade de área de captação de energia solar.
- Co-gasification of rice production wastesPublication . Andre, Rui N.; Pinto, Filomena; Miranda, Miguel; Carolino, Carlos; Costa, PaulaRice production is one of the major food sources in the world and unavoidably generates large amounts of wastes, mainly husk and straw that must be dealt in an environmentally sound and sustainable way. Traditional solutions, like burning in open fields or soil incorporation, may contribute for local pollution. Even the use of these wastes as animal food is not an appropriate solution. Plastics are also an additional waste arising from the life cycle of rice production, manufacturing and distribution. The co-gasification of these wastes was easily accomplished in a fluidized bed installation using steam mixed with air or oxygen as gasifying and fluidisation agents. By changing the gasifying agent composition it is possible to select the best conditions to co-gasify rice husks and PE wastes blends. For rice husks gasification, highest H2/hydrocarbons molar ratios were obtained using a mixture of air and steam and an equivalent ratio of 0.2. These conditions correspond to low tar emissions and very good gas yields and gas higher heating values (HHV). Co-gasification of rice husk mixed with PE enables to increase gas HHV, but also generates more tar. Nevertheless using up to 20 % of PE can be considered a promising solution to deal with this kind of wastes. Pollutants like H2S and NH3 were formed in the gasification process in acceptable amounts. Co-gasification with PE enables to decrease these pollutants. Depending on the gas end-use, the installation of a hot gas conditioning system could be needed to further decrease the contents of tar, H2S and NH3, while also promoting the conversion of hydrocarbons into H2 and CO.
- Hot treatment and upgrading of syngas obtained by co-gasification of coal and wastesPublication . Pinto, Filomena; Andre, Rui N.; Carolino, Carlos; Miranda, MiguelNowadays there is a great interest in producing energy through co-gasification of low grade coals and waste blends to increase the use of alternative feedstocks with low prices. The experimental results showed that the viability of co-gasification to process such blends and that by the right manipulation of coal and biomass or waste blends, syngas treatment and upgrading may be simplified and the cost of the overall process may be reduced. Blends of three different coal grades (sub-bituminous coal from Puertollano mines, South African bituminous coal and German brown coal) with two different types of biomass (pine and olive oil bagasse) or polyethylene (PE) were co-gasified. Blend co-gasification showed to be beneficial to reduce the negative characteristics of some coals, such as the high ash and sulphur contents, especially of Puertollano coal. Syngas obtained by these blends was hot cleaned and undesirable syngas components (tar, NH3 and H2S) were measured along the hot treatment tested, which proved to be suitable to treat syngas produced by a wide range of feedstocks. Different routes for syngas cleaning were analysed to reduce unsuitable components to values required by most common end-uses. The results obtained showed that the type of feedstock to be gasified is a key outcome on initial syngas composition, affecting greatly syngas cleaning needs, its application and the economic viability of the overall process.
- Benefits and drawbacks of energetic valorisation of Eucalyptus Globulus stumps by thermochemical processesPublication . Pinto, Filomena; Andre, Rui N.; Lopes, Helena; Neves, Diogo; Varela, Francisco; Santos, João Navalho; Miranda, Migueln the pulp and paper industry in Iberian Peninsula there is an intensive use of eucalyptus globulus that has a fast growth and a high productivity. There are large areas of forest dedicated to its growth. After 9 to 12 year rotation cycles trees are cut and the stumps are left in the fields. After 2 or 3 harvesting cycles these tree stumps are removed from the fields and considered low value biomass wastes. This corresponds to depletion on organic matter and of valuable minerals related to soil fertility. The use of these biomass wastes in thermochemical conversion processes like gasification or combustion may be a valuable alternative solution as it allows taking profit of these wastes energetic content. The solid by-products obtained by thermal conversion (ashes) may be incorporated in soils to return the valuable minerals and to ensure a good forest management system. Stumps removed from eucalyptus stands were used in combustion trials to improve the burning conditions and in gasification tests with different experimental conditions to obtain syngas suitable to be used in furnaces (chemical recover) of pulp industries. Stumps combustion and gasification processes were compared in terms of stumps energetic valorisation, gaseous emissions and gasification gas utilisation.
- Study of the experimental conditions of the co-pyrolysis of rice husk and plastic wastesPublication . Costa, Paula; Pinto, Filomena; Miranda, Miguel; Andre, Rui N.The main objective of this study is to access the technical and economical viability of using pyrolysis technology applied to the rice production main wastes to produce bio-fuels to substitute fossil fuels and electricity consumption during rice milling processes. Therefore, it was studied the effect of operating conditions (reaction temperature, initial pressure and reaction time) on products yields and quality, as well as the possible synergetic effects that may occur during the pyrolysis of these wastes. The pyrolysis experiments were performed in 1 L capacity batch reactor made of Hastelloy C276 and built by Parr Instruments. According to previous studies, the range of operational conditions studied was: 350-430 ºC for reaction temperature, 2-10 bar for initial pressure and 10-60 min for reaction time. So far, the results obtained showed that these two wastes can be processed together. The presence of PE seems to favour the biomass conversion, as PE is easily converted into liquids by pyrolysis, which increases heat and mass transfer in the reaction medium.
- Recentes avanços na literatura de reactores termoquímicos para produção de combustíveis solaresPublication . Miranda, Miguel; Bulfin, BrendanRESUMO: Este trabalho visa apresentar os principais resultados obtidos na revisão da literatura científica sobre “reactores termoquímicos para produção de combustíveis solares com recurso à energia solar de concentração”. Esta informação resulta da participação do LNEG no projeto SFERA-III mais especificamente na Subtask 8.2 - Protocols for monitoring and evaluating the performance of solar reactors. Para tal foram analisadas detalhadamente mais de 200 publicações científicas, desenvolvido um formulário personalizado em Visual Basic for Applications (VBA), desenvolvida uma base de dados em Excel para manipulação, organização e sistematização da informação. Esta informação foi agrupada em função das áreas: a) gaseificação, b) pirólise e c) reacções redox. Para cada área, a informação foi sistematizada considerando o tipo de trabalho: i) Experimental (E), ii) Modelação (M), iii) Simulador Solar (SS) e iv) Modelação em Simulador Solar (M+SS). Foi ainda desenvolvida uma análise estatística para os parâmetros experimentais temperatura, pressão, tempo, concentração solar e número de ciclos.
- Technical assessment report on solar thermal energy use in cork industry : António Almeida - Cortiças S.A.Publication . Miranda, Miguel; Salema, David; Azevedo, Pedro; Mendes, J. FarinhaABSTRACT: Nowadays, current industrial applications seek, whenever possible, to meet thermal needs on sustainable technologies that are economically viable and environmentally friendly. Despite the high potential, a number of challenges still have to be overcame. Those include maximum attainable temperatures, seasonal and daily transience in solar heat supply and its integration in the industrial processes (among others). For that purpose, the implementation of solar thermal energy into industrial applications has been recognised and addressed by IEA Solar Heating & Cooling Programme (established in 1977), in a number of different research studies, including those ones found in Task 33 and Task 49 (IEA, 2015a; IEA, 2015b; and IEA, 2016) supported by the International Energy Agency (IEA) agenda. In this area, a task called Solar Heat for Industrial Processes (SHIP) emerges, which suggested that solar thermal systems have a significant potential in the sector, even though in an early stage of progress. This activity was led primary by the Commonwealth Science and Industrial Research Organization (Fuller, 2011). General motivations to implement solar systems in cork industry include: i) economics, with respect to worldwide increasing gas prices, and ii) environmental, with respect to the carbon-dioxide footprint associated to this specific industrial sector. The main objective of this report is to assess the technical assessment of solar thermal use in the cork industry, more specifically in the António Almeida - Cortiças S.A., located in the north of Portugal. For that purpose, a close collaboration was establish with this industry through several activities namely: i) energetic audit and ii) different actions of monitoring and implementation of the Energy Consumption Rationalization Agreement (ECRA).
- Co-pyrolysis of wastes mixtures obtained from rice production: upgrading of produced liquidsPublication . Pinto, Filomena; Miranda, Miguel; Costa, PaulaThe increasing need to find alternative fuels to decrease the dependency on fossil fuels and to reduce the negative environmental impact of wastes accumulation has led to the idea of studying the energetic valorisation of different types of wastes by co-pyrolysis. Rice production process generates rice husk together with polyethylene (PE) bags that are used for rice packaging and to transport seeds and fertilizers used for rice culture. In Portugal, most of these plastic bags waste usually end up in landfills, since the amount of dirt and dust does not allow their recycling. Bio-oils produced by rice wastes pyrolysis present some undesirable properties: chemical instability, high solids content, ashes, oxygenated compounds and water, which prevent its direct use in conventional engines. On the other hand, PE pyrolysis produces around 80% w/w of liquid hydrocarbons (bio-oils) composed by a complex mixture of hydrocarbons from C5 to C20 (without the mentioned undesirable properties), 10% w/w of gases and almost no solids. Co-pyrolysis of rice husk blended with plastic wastes leads to the production of bio-oils that may be used as bio-fuels or as raw materials. These bio-oils quality can be improved by the optimisation of co-pyrolysis experimental conditions, including the use of suitable catalysts. Otherwise, liquids may be thermally upgraded to convert heavier liquid molecules into smaller ones with lower molecular weight and better fuel properties. The capability of these bio-fuels for energy production to be used during rice milling processes was analysed. Different approaches: pyrolysis, hydrogenation and pyrolysis followed by hydrogenation were analysed, considering the technical, economical and environmental viability of each process.