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- A life cycle inventory of microalgae-based biofuels production in an industrial plant conceptPublication . Branco-Vieira, M.; Costa, D.; Mata, T.M.; Martins, A.A.; Freitas, M.A.V.; Caetano, NídiaMicroalgae have been reported as a promising alternative for biofuels production. However, the use of microalgae for biofuels is still a challenge due to the intense energy use and the generation of a significant amount of biomass residues in the process. In order to analyze the environmental impacts of different technological processes for the production of biodiesel from microalgae, several studies have been published making use of the Life Cycle Assessment (LCA) methodology, which allows the recognition of the process bottlenecks and supports the identification of alternatives for a more efficient use of the feedstock. Therefore, in this study, a Life Cycle Inventory (LCI) is compiled, based on real pilot-scale process data, which was scaled-up to a microalgae biomass industrial plant for biofuel production. Values of energy, nutrients, water, and materials consumption are used to create an inventory of inputs and outputs for biomass cultivation and biodiesel production, in order to acquire data to conduct a complete LCA modeling in future studies. According to this model, to produce 1 kg of biodiesel it is necessary about 12 kg of dried algae biomass. This study supports the decision-making process in biofuel production to promote the development of sustainable pilot and large-scale algae-based industry, through the identification of critical factors.
- Sustainable development in higher education: Different teaching & learning approachesPublication . Caetano, Nídia; Felgueiras, CarlosLinking the economic, social and environmental aspects of any plan, project or activity is fundamental to act according to the sustainable development goals. These three dimensions are interrelated and interconnected in such a way that it is sometimes very hard to discriminate what their individual effects are, or on the contrary, how their joint effects are synergistic. And if this is generically a difficult task, when it comes to education the difficulty becomes even more significant, as one must be very careful defining concepts in an absolutely clear and undoubtful way. While the specialization is required to educate professionals able to accurately project and build these projects, it is now mandatory that everyone is also able to understand the causes and effects of their actions, towards sustainable development. In this Track, different teaching & learning approaches have been presented and discussed, aiming to use Higher Education as a highway to educate the professionals of the near future as strategic partners for the development of different mindsets, able to tackle the real problems.
- Antioxidant potential of extracts of Chromochloris zofingiensis cultivated in pilot-scale outdoor tubular photobioreactors under nitrogen limitationPublication . Corrêa, Priscila S.; M. Júnior, Wilson G. de; Caetano, NídiaChromochloris zofingiensis is known to be able to produce large amounts of astaxanthin and also to coproduce other molecules with antioxidant properties. Outdoor cultivation is the cheapest way for large-scale production; however, the unstable weather conditions can hinder the productivity of the biomass and the target product. The final biomass (0.92 g·L−1) and total carotenoids (0.55 mg·g−1) concentration achieved in outdoor cultivation (i.e., during autumn in Porto, Portugal) had no statistically significant difference compared to control cultivation (i.e., constant temperature, 18 °C, and light intensity, 4000 lx) (1.36 g·L−1 and 0.56 mg·g−1, respectively), however the biomass productivity was about threefold lower. Regarding the antioxidant potential, methanolic extracts from outdoor cultivation presented one of the highest values for radical scavenging ability (44.2 %) and ferrous-ion chelating ability (59.1 %), similarly to the results obtained by ethanolic extracts from indoor cultivation under nitrogen limitation. Highest total antioxidant capacities were observed in ethanolic extracts varying from 120.0 to 185.2 mg GAE·g−1.
- Teaching sustainable development in higher education - Changing attitudes in a digital eraPublication . Caetano, Nídia; Felgueiras, CarlosSustainable Development (SD) is an increasingly important topic. Humanity has an absolutely vital dependence on a set of natural and artificial resources. The advancement of knowledge needed to adequately manage these resources has traditionally been achieved through specialization. In this strategy of dividing and ruling, what was gained in depth was lost in coverage. Yet, the most recent problems are intensely interdisciplinary, revealing that the previous specialization strategy is currently not wrong, but clearly insufficient. Strangely (or not), various courses in higher education continued to follow the traditional specialization strategy. As a result of this state-of-affairs, several conferences currently exist, both in the field of Education or in the field of Sustainability, but it has been particularly difficult to attract participants to deepen the theme of Teaching Sustainability. As an attempt to contribute to clarifying the needs of the present and future, this TEEM’21 track presents itself as a space for presenting results and debating works and strategies that involve both domains: Teaching and Sustainability.
- A multicultural approach to teach sustainabilityPublication . Caetano, Nídia Sá; Rocha, João; Quadrado, José Carlos; Cardoso, José Marílio; Felgueiras, CarlosGlobalization is a trend that covers all society perspectives in general, and higher education in particular. The main traditional objective of higher education institutions has been to prepare domestic students with a given set of skills. Research competition and University’s rankings, as well as the need to reach other publics, pushed them towards internationalization. The exchange of students across the EU is a well-known reality which success is largely due to cultural similarities. However, a set of issues raises in importance when students from different cultures are involved. ISEP proposed a Summer Course aiming both to increase its level of internationalization and to verify how the institution is able to host foreign students. Therefore was organized, in July 2014, ISEP’s first Engineering for Sustainable Development Summer Course, with a layout specifically designed to address those questions. In our study, and in order to gain from an intensive and multicultural experience, the class included equal number of Korean and Portuguese students to develop work under the framework of sustainability, a theme chosen in order to foster consensus. This work reports some results from this experience, which included a Problem Based Learning (PBL) approach, and points out new directions: PBL revealed to be a promoting integration way; the inclusion of multiple cultures allowed the analysis of different perspectives which otherwise would not have been succeed; institutional academic/social services need to be adapted in order to receive non-Portuguese speaking students; there is a need for further adequate accommodation able to receive a larger number of international students.
- Educating global engineers with EPS@ISEP: The 'pet tracker' project experiencePublication . Borzecka, Aleksandra; Fagerstrom, Anton; Costa, Artur; Gasull, Marti Domenech; Malheiro, Benedita; Castro Ribeiro, Maria Cristina De; Silva, Manuel; Caetano, Nídia; Ferreira, Paulo; Guedes, PedroThe European Project Semester (EPS) is a one-semester capstone project/internship programme offered to engineering, product design and business undergraduates by 18 European engineering schools. EPS aims to prepare future engineers to think and act globally, by adopting project-based learning and teamwork methodologies, fostering the development of complementary skills and addressing sustainability and multiculturalism. Since 2011, the EPS@ISEP programme offers a set of multidisciplinary projects to multicultural teams of students, so that each team element can bring to the project its previous knowledge and background experience. In the spring of 2013, a team choose to develop a pet tracker to provide pet owners with information regarding the whereabouts of their pets and, above all, to reduce the number of pets lost. After analysing related products, the team decided to add extra features for product differentiation. Combining a triple-axis accelerometer, a low cost GPS receiver and the GSM/GPRS communication technology, the team designed a system providing pet location, tracking, map display and activity monitoring services. This paper describes the development process of the Pet Tracker system, comprising a wearable device for pets and a website for pet owners.
- Valorização da borra de café: Recuperação de taninosPublication . Vilar, Mickael; Júnior, Wilson; Caetano, NídiaO elevado consumo mundial de café origina grande produção de resíduos. A borra (resíduo de extração) apresenta um grande potencial de contaminação devido à sua constituição (taninos, cafeína e polifenóis, entre outros compostos de elevado valor). Assim, a sua deposição, muitas vezes em condições descontroladas, representa um risco para o ambiente e perda de recursos. Neste trabalho pretendeu-se otimizar as condições de extração de taninos (composto de valor) em amostras de diferentes proveniências (cápsulas de café, borra de cafetarias, café não extraído). Os solventes testados neste trabalho foram água, acetona, metanol e etanol, tendo sido concluído que o solvente mais eficaz para a extração dos taninos foi a acetona à temperatura ambiente. A borra que apresentou uma maior abundância de taninos foi a proveniente de cápsulas, tendo sido possível recuperar 36,1 mgtaninos /100 gborra. Da borra de cafetarias húmida, extraída com etanol em 2 contactos, recuperaram-se 64,0 mgtaninos /100 gborra. O sucesso deste processo pode fomentar a redução da deposição descontrolada, com o desenvolvimento de uma indústria baseada em biorresíduos (borra), contribuindo para a criação de postos de trabalho e a produção de um bioproduto de valor, e para a dinamização da bioeconomia circular e a valorização dos biorresíduos.
- Sustainable energy systemsPublication . Caetano, Nídia; Vale, Zita; Jorgensen, Bo Norregaard; Felgueiras, CarlosThis Special Issue, therefore, aims to contribute to the “Sustainable Energy Systems” agenda through advanced scientific and multi-disciplinary knowledge, combined to improve energy security and performance. We therefore invite papers on innovative technical developments, reviews, case studies, analytical, as well as assessments, from different disciplines, which are relevant to “Sustainable Energy Systems”. These include smart grids, renewable energy systems, energy storage systems, life cycle analysis of energy systems, zero energy buildings, electric and hybrid vehicles, financial and economic analysis of energy systems, smart systems, energy management and big data, energy policy, novel energy sources, and renewable-based generation, among others.
- Adding Value to Tannery Fleshings Part I – Oils and Protein Hydrolysates – Production and ApplicationPublication . Bragança, I.; Crispim, Alfredo; Sampaio, A.; Ramalho, Elisa; Crispim, F.; Caetano, Nídia; Silva, P. C.The tanning industry generates a high quantity of solid wastes. Therefore, there is a need to create valorization [added value] options for these wastes. The present work had as its main objective creating added value by production of fat and hydrolyzed protein. To this end, fleshings were treated by hydrolysis with regard to the influence of various factors. The best result was found for a temperature of 60°C, 4 hours of hydrolysis, 2% of enzyme and 100% of water, with a fat extraction yield of 93%. The fat obtained through the hydrolysis process was used to produce sulphated oils. The protein hydrolysate was concentrated to about 40% of solids content and used to prepare co-products of protein hydrolysate and glutaraldehyde. Sulphated oils were applied in leather fatliquoring and the different protein hydrolysates were tested in leather retannage. The leather samples obtained were evaluated by physical-mechanical tests and the results were compared to those obtained through a standard process. The results were very satisfactory and, in some cases better than the specified standard. The process of adding value to this waste results in a double advantage for the leather industry, reducing the environmental impact and allowing production of alternative products for leather fatliquoring and retannage.
- Increase in antioxidant activity of Nannochloropsis sp. through stress cultivation conditionsPublication . Coimbra, R.S.T.; Corrêa, P:S.; Saraiva, J.A.; Lemos, Á. T.; Tavares, J.; Caetano, N.S.(Introduction) Nowadays, there is a great demand on the use of microalgae, or their derivatives, as novel foods or food ingredientes. Microalgal supplements provide an optimal solution to balance the diet of people who do not consume fish, promoting a healthy diet and reducing metabolic and aging pathologies with an environmentally and economically sustainable approach (1). The genus Nannochloropsis sp. has a high content of antioxidants, specific vitamins, PUFAs (in particular EPA) and is suitable for intensive culture thus being a good candidate for human consumption (1). This research work was done under the scope of the project Nº 33784: EXTRATOTECA – High Value Added Microalgae Extracts.