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- Biogas reforming as a sustainable solution for hydrogen production: Comparative environmental metrics with steam-methane reforming and water electrolysis in the Portuguese contextPublication . Bento, Cláudia; Lopes, Tiago; Rodrigues, Pedro; Gírio, Francisco; Silva, CarlaABSTRACT: This study delves into the dynamics of hydrogen production, with a specific focus on biogas reforming (BGSMR) for hydrogen generation. It compares the environmental impact of this solution with hydrogen production from natural gas-steam reforming (NGSMR) and commercial electrolysis in the Portuguese context. Various metrics, including carbon footprint, water depletion, energy utilization, and waste valorization are employed for a comprehensive comparison. The assessment explores the impact of operational parameters and different off-gas combustion scenarios, incorporating water recycling practices. Due to challenges in obtaining detailed data on the actual reforming process, the study relies on process simulation techniques, primarily using DWSIM. Commercially available data for water electrolysers were used for comparison. In the context of decarbonizing power systems, hydrogen from water electrolysis emerges as a competitive option only in a scenario where the power system is 100% reliant on renewable sources, particularly with respect to the carbon footprint metric. Biogas systems, characterized by near-zero carbon emissions, stand out as a favourable option from the near future to the long run. This research contributes valuable insights into the dynamics of hydrogen production, shedding light on environmentally viable alternatives across a range of power system scenarios.
- Atlas Nacional do H2 Verde SustentávelPublication . Ponce Leao, Maria Teresa; Simoes, Sofia; Simões, Teresa; Quental, Lídia; Catarino, Justina; Amorim, Filipa; Brás, Teresa; Patinha, Pedro; Lopes, Tiago; Rodrigues, Carlos; Machado, Susana; Rangel, C. M.; Gírio, Francisco; Picado, AnaRESUMO: O "Atlas Nacional do H2 Verde Sustentável" tem como objetivo apoiar o processo de decisão quanto à localização de projetos de produção de hidrogénio verde no território de Portugal continental. O Atlas foi desenvolvido pelo LNEG em colaboração com várias entidades públicas e privadas nacionais. De uma forma mais geral, apoia à a transição para um país neutro em carbono, desenvolvendo uma economia de baixo carbono, liderando em inovação e desenvolvimento tecnológico.
- Admissibility Grid to Support the Decision for the Preferential Routing of Portuguese Endogenous Waste Biomass for the Production of Biogas, Advanced Biofuels, Electricity and HeatPublication . Crujeira, Teresa; Trancoso, Maria Ascensão; Eusebio, Ana; Oliveira, Ana Cristina; Passarinho, Paula; Abreu, Mariana; Marques, Isabel Paula; Marques, Paula; Marques, Susana; Albergaria, Helena; Pinto, Filomena; Costa, Paula; Andre, Rui N.; Girio, Francisco; Moura, PatríciaABSTRACT: A methodology was developed to assess the allocation of different types of endogenous waste biomass to eight technologies for producing electricity, heat, biogas and advanced biofuels. It was based on the identification of key physicochemical parameters for each conversion process and the definition of limit values for each parameter, applied to two different matrices of waste biomass. This enabled the creation of one Admissibility Grid with target values per type of waste biomass and conversion technology, applicable to a decision process in the routing to energy production. The construction of the grid was based on the evaluation of 24 types of waste biomass, corresponding to 48 sets of samples tested, for which a detailed physicochemical characterization and an admissibility assessment were made. The samples were collected from Municipal Solid Waste treatment facilities, sewage sludges, agro-industrial companies, poultry farms, and pulp and paper industries. The conversion technologies and energy products considered were (trans)esterification to fatty acid methyl esters, anaerobic digestion to methane, fermentation to bioethanol, dark fermentation to biohydrogen, combustion to electricity and heat, gasification to syngas, and pyrolysis and hydrothermal liquefaction to bio-oils. The validation of the Admissibility Grid was based on the determination of conversion rates and product yields over 23 case studies that were selected according to the best combinations of waste biomass type versus technological solution and energy product.
- Evaluation of the potential of biomass to energy in Portugal : conclusions from the CONVERTE projectPublication . Abreu, Mariana; Reis, Alberto; Moura, Patrícia; Fernando, Ana Luisa; Luís, Gabriel; Quental, Lídia; Patinha, Pedro; Gírio, FranciscoABSTRACT: The main objective of the Portuguese project "CONVERTE-Biomass Potential for Energy" is to support the transition to a low-carbon economy, identifying biomass typologies in mainland Portugal, namely agri-forest waste, energy crops and microalgae. Therefore, the aim was to design and construct a georeferenced (mapping) database for mainland Portugal, to identify land availability for the implementation of energy crops and microalgae cultures, and to locate agricultural and forestry production areas (including their residues) with potential for sustainable exploitation for energy. The ArcGIS software was used as a Geographic Information System (GIS) tool, introducing the data corresponding to the type of soil, water needs and edaphoclimatic conditions in shapefile and raster data type, to assess the areas for the implantation of the biomass of interest. After analysing the data of interest in each map in ArcGIS, the intersection of all maps is presented, suggesting adequate areas and predicting biomass productions for the implementation of each culture in mainland Portugal. Under the conditions of the study, cardoon (72 kha, 1085 kt), paulownia (81 kha, 26 kt) and microalgae (29 kha, 1616 kt) presented the greater viability to be exploited as biomass to energy in degraded and marginal soils.
- Biotechnology of polysaccharides for biofuels and bio-based products [Comunicação oral]Publication . Gírio, Francisco
- A thermotolerant xylan-degrading enzyme is produced by Streptomyces malaysiensis AMT-3 using by-products from the food industryPublication . Nascimento, Rodrigo Pires do; Reis, Alberto; Gírio, Francisco; Pereira Jr, Nei; Bon, Elba Pinto da Silva; Coelho, Rosalie Reed RodriguesABSTRACT: This study evaluated the production of endoxylanases by Streptomyces malaysiensis AMT-3 in submerged fermentation using by-products of the food industry at 28ºC. In shake-flasks experiments, the highest endoxylanase activity of 45.8 U.mL-1 was observed within 6 days in a medium containing (w/v) 2.5% wheat bran and 1.2% corn steep liquor. The same culture conditions were used to evaluate the enzyme production in a 2 L stirred tank reactor under different agitation (300, 450 and 600 rev.min-1) and aeration (30 and 60 L.h-1) conditions. The use of 450 rev.min-1 coupled to an aeration of 90 L.h-1 resulted on 81.3 U.mL-1 endoxylanase activity within 5 days. The effect of temperature and pH on endoxylanase activity and stability showed the highest activity at 60 ºC and pH 6.0. Zymography showed the presence of three xylanolytic bands with molecular masses of 690, 180 and 142 kDa. The results showed that the thermotolerant actinobacterial endoxylanase can be produced in high titers using by-product of the food industry.
- Ação concertada das renováveis participação portuguesaPublication . Joyce, A; Camelo, Susana; Gírio, FranciscoRESUMO: A Ação Concertada das Renováveis (CA-RES) é uma iniciativa conjunta de 27 Estados-Membros da EU, da Noruega, da Islândia e da Comissão Europeia (DG ENER, EASME), coordenada pela Agência Austríaca de Energia com vista a apoiar a implementação da Diretiva Europeia de Energias Renováveis. O projeto foi cofinanciado pelo Programa Horizonte 2020 da União Europeia e corresponde ao item B.2.2. “Coordination of Renewable Energy policies development and implementation through concerted actions with Member States” of the HORIZON 2020 WORK PROGRAMME 2014–2015 10. Secure, clean and efficient energy. A terceira fase da Ação Concertada (CA-RES 3) apoia a transposição da Diretiva das Energias Renováveis 2009/28/CE e a sua reformulação na nova Diretiva 2018/2001/UE (RED II). Os objetivos da Concerted Action estando diretamente relacionados com a transposição e implementação da Diretiva RES permitem também fomentar sinergias e criar novas oportunidades para explorar abordagens comuns em áreas específicas das energias Renováveis.
- Hydrothermal pretreatment of several lignocellulosic mixtures containing wheat straw and two hardwood residues available in Southern EuropePublication . Silva-Fernandes, Talita; Duarte, Luís C.; Carvalheiro, Florbela; Loureiro-Dias, M. Conceição; Fonseca, César; Gírio, FranciscoThis work studied the processing of biomass mixtures containing three lignocellulosic materials largely available in Southern Europe, eucalyptus residues (ER), wheat straw (WS) and olive tree pruning (OP). The mixtures were chemically characterized, and their pretreatment, by autohydrolysis, evaluated within a severity factor (log R0) ranging from 1.73 up to 4.24. A simple modeling strategy was used to optimize the autohydrolysis conditions based on the chemical characterization of the liquid fraction. The solid fraction was characterized to quantify the polysaccharide and lignin content. The pretreatment conditions for maximal saccharides recovery in the liquid fraction were at a severity range (log R0) of 3.65–3.72, independently of the mixture tested, which suggests that autohydrolysis can effectively process mixtures of lignocellulosic materials for further biochemical conversion processes.
- Deconstruction of the hemicellulose fraction from lignocellulosic materials into simple sugarsPublication . Gírio, Francisco; Carvalheiro, Florbela; Duarte, Luís C.; Lukasik, Rafal M.Hemicelluloses hold a great promise for the production of added-value compounds in the biorefinery framework. Specifically, the xylan-rich hemicelluloses from hardwoods and agro-industrial residues present themselves as effective feedstock choices for the biotechnological production of xylitol. This paper reviews the various hemicellulose structures present in such materials and critically evaluates the available processing options to produce xylose-rich fermentable hydrolysates. Currently, acid-based processes still present the best trade-off between operation easiness and xylose yield and recovery. Nevertheless, concerns regarding the impact of the fractionation processes on the overall upgradability of all biomass fractions (namely, cellulose and specially lignin) may turn the route to other strategies. Specifically, the combined/sequential use of processes targeting hemicellulose dissolution and hydrolysis might hold great promise for the economical production of pentoses.
- Correction: Correia et al. Sustainability Assessment of 2G Bioethanol Production from Residual Lignocellulosic Biomass. Processes 2024, 12, 987Publication . Correia, Bárbara; Matos, Henrique A.; Lopes, Tiago; Marques, Susana; Gírio, FranciscoError in Table: In the original publication [1], there was a mistake in Table 8 as published. The presented cost of purchased equipment and Total CAPEX cost shall not differ between the two scenarios. The purchased equipment cost and Total CAPEX cost should be, for both scenarios, 21.35 and 75.66M€, respectively. The corrected Table 8 appears below. The authors state that the scientific conclusions are unaffected. This correction was approved by the Academic Editor. The original publication has also been updated.