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LSRE-LCM - Artigos em Livros de Atas (participação em conferências)

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  • Energy Efficiency and Sustainability in an Aquaponic Greenhouse Supported by IoT
    Publication . Galvão, João; Santos, Pedro; Aires, Luis; Ribeiro, Vânia; Neves, Filipe
    The increasing demand for agricultural crops and the necessity to reduce environmental impacts from traditional agriculture have led to the emergence of sustainable production systems such as hydroponics and aquaponics. These soil and pesticide-free systems require less water and fertilizers but need electrical energy and controlled greenhouse environmental conditions to be highly productive. This work presents a monitoring and management system for environmental parameters inside an aquaponic greenhouse, that allows the manager to assess in real-time the working status of the aquaponic system, helping in the detection of critical conditions that require a quick decision. This system was developed to measure, through IoT sensors network, the temperature and the relative humidity of the air, the temperature, pH and the electrical conductivity of the water that contains the dissolved nutrients that feed the growth of the plants. It is possible to visualize the measured parameters via the Internet, on a dashboard, in a mobile application and store these variables in a database. To further increase the sustainability of the aquaponic greenhouse, the electricity consumed during its activity will be produced locally by photovoltaic technology. The technologies proposed in this work may promote the emergence of small models of greenhouses, implemented by communities and populations, reducing production energy costs and transportation resources.
  • Recycling of PET fines waste by density separation: a way to circularity of plastic
    Publication . Heleno, M. L.; Oliveira, N. S.; Gaspar, M.; Silveira, A.; Vasco, J.
    Plastic is one of the most used materials due to its specific characteristics such as high flexibility and impact resistance, low cost, formability, light weight and recyclability. In this set, polyethylene terephthalate (PET) based materials are among of the most used plastics on the packaging market worldwide. The European strategy for plastics aims to modify the processes of design, production, use and recycling of plastics. It becomes crucial to study solutions to enhance the circularity of plastics in recycling processes. Therefore, it is mandatory to evaluate the potential separation of PET fines resulting from the recycling process of PET bottles (post-consumer waste), which are still contaminated by other polymers and other materials. The recovery of PET fines was successfully achieved with a multistage density plastics separation process, consisting on the use of solutions of different densities and ensuring the adequate wettability of the residues in the solutions. The addition of this multistage separation process by plastics density, improves PET fines recovery, by achieving 91.7% of pure PET fines from plastic material waste.
  • Sustainability study of limestone quarry waste into value-added products: PCC and GCC
    Publication . Monteiro, S. M. C. S.; Jorge, Muanassa; Heleno, M. L.; Oliveira, N. S.; Alves, M. L.; Veiga, A.; Silva, A.
    Calcium carbonate can be obtained naturally from limestone, chalk, marble, and other sedimentary rock forms. Ground calcium carbonate (GCC) and precipitated calcium carbonate (PCC) are two materials that can be produced from natural calcium carbonate. The future of GCC and PCC is promising since they are linked to industries with high demand, such as packaging, building & construction, transportation, and industrial applications, with an expected compound annual growth rate higher than 4% until 2027. This research focuses on the production of GCC and PCC through a comparative analysis that identifies the macro conditions that become advantageous to produce and commercialising PCC in a quarry context. This allows a valorisation of the limestone waste resulting from the extraction operations, converting it into by-products of the process. Not all existing limestone quarries in the Serra de Aire e Candeeiros region are suitable sources of raw material to produce PCC. The five extraction poles were identified with the potential for extracting suitable raw materials, associated with several companies dedicated to the extraction operation in these quarries.
  • Qualitative analysis of the limestone waste potential from the Serra de Aire e Candeeiros quarries
    Publication . Monteiro, S. M. C. S.; Jorge, Muanassa; Oliveira, N. S.; Alves, M.L.; Veiga, A.; Silva, A.
    The mountains of Aires and Candeeiros are part of the Maciço Calcário Estremenho where the landscape is predominantly made up of limestone. The limestone explored in the region has been the driver of social and cultural development, contributing significantly to the local economy. This emerging concern has motivated public and private organisations to develop solutions to improve the sector's sustainability. The present work aims to evaluate the limestone waste potential to produce precipitated (PCC) and ground (GCC) calcium carbonate in the region by surveying the local extraction industries that fulfil the defined minimum requirements to produce high quality PCC and GCC. The results allowed to stablish an estimate of the amount of waste resulting from the extraction process. The conversion of these wastes into PCC or GCC constitutes a possibility of recovery into by-products, allowing use in noble and profitable applications and contributing to the circular economy and the sustainability of the sector.
  • Sustainability Performance of Buildings in the Project Stage—Residence Students
    Publication . Heleno, Lizete; Baptista, Pedro; Marta Gregório; Oliveira, Nelson S.; Monteiro, Silvia
    In recent years, the concept of sustainable construction has been promoted by demand and by regulations. Several methodologies to assess the sustainability of the construction have been spread across the world, by several countries for almost all continents. This study focuses on the most used construction sustainability assessment methodologies, which were compared with the Portuguese methodology, LiderA. It was found that the LiderA is the sustainability system with the greatest number of relevant criteria, considering the three dimensions of sustainability, environment, economy and social. Considering the 5 phases of the construction life cycle, the importance to apply these methodologies in construction is crucial in the early phases. It can help to draft the sustainability classification of the building. To apply the LiderA was used a residence of students, a building composed of apartments, in the phase of planning. All of the 40 criteria from the LiderA were classified from F to A++, according to the project of the residence of students. The final classification, as it was projected, was A, meaning that the building has an environmental performance 50% higher than usual practice. The category of criteria with the highest contribution was the category of quality of service and resilience, with a percentage of achievement greater than 50%. The local dynamics and the resources category were the categories with the lowest contribution, and they have the potential to be reevaluated by the building promoter, since it has the potential to improve the sustainability classification of the residence of students.
  • Sustainability Assessment of Building Rehabilitation Solutions: The Mid 70s Portuguese Building
    Publication . Reis, Alexandre; Heleno, Lizete; Monteiro, Silvia; Oliveira, Nelson S.
    The Energy Performance of Buildings Directive (EPBD) establishes improvements to buildings’ comfort conditions and energy performance, bringing them closer to buildings with almost zero energy needs, namely the Nearly Zero Energy Building (NZEBs). The assessment tools for sustainable construction, more recognized internationally, are LEED and BREEAM, and in Portugal is the LiderA. The application of those tools promotes energy efficiency and decarbonization of buildings, as referred to in the Portuguese Long-Term Strategy for Building Renovation (LTRS-PT) until 2050. In this case, a house representative of the construction of the period between 1971 and 1980 in Portugal was chosen to evaluate environmental sustainability using LiderA. In the current conditions, the LiderA rating class of the house was D. To improve the performance of the building were identified balanced rehabilitation solutions without excessive automation. The presented solutions should avoid transforming the house into a complicated device with operational difficulties or specialized operation. In this way, the proposed interventions in the building and systems are based on renewable sources, prioritizing energy and water efficiency. Furthermore, as a contribution to the health and well-being of the occupants, we considered measures related to indoor air quality (IAQ) and noise minimization. In addition, the encouragement of native species has contributed to ecological enhancement. With that proposals, the house rating class using LiderA improved from class D to class A+.
  • Ink Removal on Plastic Films Printed by Flexography
    Publication . Bozzola, Fernando; Nascimento, Bruna Guilherme do; Vasco, Joel C.; Silva, Nelson; Lagoa, Fernando; Capela, Carlos; Heleno, Lizete; Gaspar, Marcelo; Oliveira, Nelson S.
    Plastics are key engineering materials for our society and economy, mainly due to their multifunctionality and ease of processing. Nonetheless, their main drawback is related to the fact that when these cannot be reprocessed, they do generate waste, which leads to several environmental impacts. Therefore, considering plastics’ circularity, minimizing their waste, and the resulting impacts, stresses the need for these to be recyclable. One of the main challenges that concern their recyclability is the deinking of plastic films when printed by flexography. The current technology uses non-bio-based surfactants and non-renewable surfactants, which are harmful to the environment. Therefore, the main objective of current research is to develop an environmentally sustainable process for ink removal on printed post-industrial flexible plastic films using bio-based surfactants. This process focuses on obtaining a deinked plastic that may be reprinted, avoiding this way for inappropriate disposal or reprocessing problems. The value increase of upcycling such post-industrial waste makes it possible to match the quality of the virgin plastic, which is key to carrying out an effective cost analysis of recycled plastic when compared to the new plastic films. Dedicated laboratory deinking procedures were undertaken with transparent polyethylene films printed by flexography with different conditions. Preliminary results show the dedicated experimental ink removal procedure using bio-based surfactants to be effective and environmentally sustainable.
  • Feasibility Study of the PET Fines Incorporation into Recycling Processes
    Publication . Nascimento, Bruna Guilherme do; Bozzola, Fernando; Vasco, Joel C.; Parnigoni, Milena; Capela, Carlos; Heleno, Lizete; Gaspar, Marcelo; Oliveira, Nelson S.
    Circular economy principles focus on the need to preserve natural resources and foster the use of environmentally sustainable practices. Concerning the use of plastics in a circular economy, increasingly demanding solutions have to be developed towards the zero-waste goal sought after by researchers and society alike. Particular attention has been put into the recycling of PET, mainly due to its wide spectrum of use and, consequently, to large volumes of related waste. The PET mechanical recycling process requires these waste materials to be shredded into PET flakes. Following such a procedure, these flakes are pelletized to be used again as feedstock. Considering the main stages of the mechanical recycling processes, which include plastic screening, shredding and washing, significant amounts of end waste materials are generated. This end-waste integrates small scale particles that are designated by plastic fines. Concerning the PET recycling process, the PET fines resulting from its mechanical recycling are not currently valued due to several technical issues, such as their high contamination level and the complexity of sorting them from other small-size particles. Current research focuses on the feasibility of incorporating these PET fines into the film/injection extruders, avoiding this way the need for an intermediate pelletization stage. To allow for such direct incorporation of PET fines into recycling processes, different decontamination and sorting solutions were implemented and tested. The current study is based on analyzing the mechanical properties of PET fines, using laboratory tests such as FTIR, DSC, MFI, moisture content, tensile tests and bending tests. Preliminary results allow foreseeing the successful direct incorporation of PET fines into PET recycling.
  • Oxidative Stress and Inflammatory Response of Skin Fibroblasts Exposed to Chlorpyrifos
    Publication . Silva, Zélia; Almeida, Danielle; Marques-da-Silva, Dorinda; Lagoa, Ricardo; Videira, Paula A.
    Chlorpyrifos (CPF) is a widely used insecticide. The aim of this work was to study the effect of CPF in skin fibroblasts exposed to concentrations detected in human skin and unleash underlying cellular mechanisms. Fibroblasts were exposed to different concentrations (0.36–250 µM) of CPF pure alone or in a commercial CPF mixture (Lethal 20) for 6 days. In conclusion, prolonged exposure to 250 µM of CPF pure and 125 µM of Lethal 20 caused a significant loss of the fibroblast´s viability. Moreover, the toxicity of this pesticide in fibroblasts is evidenced by the induction of oxidative stress and stimulation of the production of interleukin (IL)-6.
  • Permeation of chlorpyrifos in ex vivo pig skin – Experimental conditions to get closer to human exposure
    Publication . Silva, Dorinda
    Track 3: Environmental chemistry and exposure assessment: analysis, monitoring, fate and modeling 3.06.P-Tu151 Permeation of Chlorpyrifos in Ex Vivo Pig Skin - Experimental Conditions to Get Closer to Human Exposure to air pollutants is not limited to inhalation risk and dermal contact is gaining increasing interest with the possibility to represent a risky carcinogenic route. Chlorpyrifos is a broad-spectrum organophosphorus pesticide used for aerial and ground-based treatments with different permeation values being reported for human skin. Despite the recommendations of the organisation for economic co-operation and development (OECD) to use 50% of ethanol in the receptor fluid for skin permeation of lipophilic compounds (as chlorpyrifos), this condition was suggested to exaggerate its permeation.