LSRE-LCM - Artigos em Livros de Atas (participação em conferências)
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Percorrer LSRE-LCM - Artigos em Livros de Atas (participação em conferências) por Objetivos de Desenvolvimento Sustentável (ODS) "12:Produção e Consumo Sustentáveis"
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- Design of Pyrolysis System to Convert Waste Plastic to FuelsPublication . Oliveira, Nelson S.; Pardo, Michael; Capela, Carlos; Gaspar, Marcelo; Vasco, Joel; Heleno, LizeteThe conventional recycling technology to process waste plastic, mechanical recycling, is not suitable to recycle waste thermoplastic with high content of contamination. Pyrolysis is a promising technology since it can convert into valuable products, such as fuels and monomers. This study focused on the design of the pyrolysis equipment for waste plastic based on polyolefins. The feeder of waste plastic is a worm screw conveyor that will be in a pre-heating system. The batch reactor has support for catalyzer and can operate between 300 up to 600 ºC with attached induction system for heating. The output flows into condenser in series to separate two liquid phases and gases, depending on its boiling point. The 3D model was done with SolidWorks, control system modelled in CADe SIMU and particle simulation with FloXpress.
- Energy Efficiency and Sustainability in an Aquaponic Greenhouse Supported by IoTPublication . Galvão, João; Santos, Pedro; Aires, Luis; Ribeiro, Vânia; Neves, FilipeThe 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.
- Feasibility Study of the PET Fines Incorporation into Recycling ProcessesPublication . 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.
- Ink Removal on Plastic Films Printed by FlexographyPublication . 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.
- Permeation of chlorpyrifos in ex vivo pig skin – Experimental conditions to get closer to human exposurePublication . Silva, DorindaTrack 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.
- Production and Material Types for Pallets: A ReviewPublication . Pulgar, Alejandro; Oliveira, Nelson S.Pallets are used extensively in the supply chain for the transportation of goods between suppliers, manufacturers, distributors, and retailers. This article reviews pallet production, its mechanical properties related to material options (according to European standards and industrial applications) and management systems. In the global supply chain, polymer, metal, and composites pallets compete in line with the concept of sustainable development. The supply chain requires pallets according to specific characteristics, such as sizing, maximum load capacity, durability (lifespan), cost and more information is needed about their environmental impacts. Some types of pallets (stringer and blocks) can have several configurations, number, width and spacing. Furthermore, the pallets management system is divided in three models; EMP (extensive management of pallets), TPO (transfer pallet’s ownership) and PR (pallet rent), where suppliers, distributors and retailers select the most suitable option. The systematic review of the literature identified 15 documents with the key methodological elements, such as, specifications, inventory data, goals, and system boundaries for a life cycle assessment of pallets.
- Qualitative analysis of the limestone waste potential from the Serra de Aire e Candeeiros quarriesPublication . 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.
- Recycling of PET fines waste by density separation: a way to circularity of plasticPublication . 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.
- Summer production of lettuce grown in a hydroponic system using wastewaterPublication . Vieira, Judite; Vaz, Daniela C.; Santos, Ounísia; Pala, HelenaPopulation growth leads to an increasing need for food production, which causes negative impacts on the environment, namely a higher use of water, and fast depleting land. The search for more efficient technologies in the agricultural sector aims for sustainable production, reducing water consumption and waste, inducing wastewater reuse, and the use of soilless cropping systems as an alternative to traditional agriculture. The aim of this study was to evaluate the growth of lettuces in wastewater from an urban treatment plant in a small hydroponic system, without recirculation, during the summer period, when the scarcity of water is higher thus increasing the impacts of crop production with soil. The crop growth was studied under three different conditions: wastewater (after primary or secondary treatment); wastewater with potassium supplementation; and synthetic medium, as control. Physical and chemical parameters of the wastewater, crop growth, and the environmental conditions of the greenhouse were monitored. At end of the assay the crop fresh weight was determined, and toxicity analysis were carried out through cell viability assays with the Caco-2 cell line. Results point to a limited crop growth in the wastewater with a secondary treatment, due to low nutrients concentrations, which affects the plants fresh weight. Solids load, pH value and nitrite concentration in wastewater seem to affect crop growth. Wastewater with a primary treatment had a large organic load, and the system allowed the removal of over 98% of BOD5 and the removal of over 68% of COD. The system provided an improvement in the wastewater quality, allowing the removal of the nutrient load (minimum value) of 43% N, 53% K, and 46% P (total phosphorus). For extract percentages up to 1% (w/v) there is no evidence of toxicity associated with the lettuce culture from the hydroponic system. The reuse of urban wastewater in hydroponics seems to be a sustainable promising technology that may complement the lack of crop production in soil due to water scarce.
- Sustainability Assessment of Building Rehabilitation Solutions: The Mid 70s Portuguese BuildingPublication . 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+.