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- Local waste agroforestry managment - biomass to energy analysis with LCAPublication . Brás, Isabel; Ferreira Silva, Maria Elisabete; Ferreira, José; Raimondo, Roberta; Saetta, Rafaella; Fabricino, MassimilainoTo enable the protection of forests against rural fires are foreseen a set of measures for plan-ning and intervention, reduction their risk and impacts. Forest residues collecting centers are being created in Portugal, to reduce undesired thermal charge in nature and for biomass further valorization. Keeping this in mind, one of the strategies is the energy recovery from these residues in bi-omass power plants that were built in strategic locations. The biomass is mostly natural residu-al forest, agricultural and garden wood and green materials The present work aims to study its environmental impact. The Life Cycle Assessment methodology, using SimaPro 9.3.0.3 PhD software, was applied to identify the burden of this process and the environmental categories most relevantly affect-ed. Data achieved showed the importance of the valorization of residual biomass for energy production, reduction the impact categories of abiotic depletion due to fossil fuels, global warming, human toxicity and eutrophication.
- Risk assessment of reusing treated water from the Viseu Sul WWTP for irrigation and similar usesPublication . Santos, Lenise; Ferreira, José; Silva, Maria; Simões, Luis; Ferreira, Miguel; Brás, IsabelDue to the growing water scarcity, the reuse of treated wastewater arises as a possibility for sustainable water management. However, it is necessary to evaluate the possible risks associated with its activity. This study aims to develop a risk assessment of water for reuse, in terms of public health and water resources, for production and internal use by the Viseu Sul Wastewater Treatment Plant (WWTP) and external use in irrigation of green spaces in Viseu. The methodology used was a semi-quantitative risk assessment. The results demonstrated the viability of the production and use of Reused Water by the Viseu Sul WWTP, with an overall risk to public health of 0.68, and for use in irrigating green spaces in Viseu, with an overall risk of 0.75. The overall risk to water resources was 2.33 for nitrogen and phosphorus and 0.78 for E. coli. All risks were considered insignificant, considering the criteria defined by the method. Based on the information presented, it can be inferred that the use of treated wastewater to meet Viseu's water needs is a viable option.
- Changes in the content and composition of the extractives in thermally modified tropical hardwoodsPublication . Esteves, Bruno; Ayata, Umit; Cruz-Lopes, Luísa; Brás, Isabel; Ferreira, José; Domingos, IdalinaChemical composition of wood is known to change during thermal treatments. Two species grown in Turkey, afrormosia (Pericopsis elata) and duka (Tapirira guianensis) were heat treated according to Thermowood® method. Lignin, cellulose, hemicelluloses and extractives in dichloromethane, ethanol and water were determined. Wood extracts were analysed by gas chromatography with mass detection and existing compounds were identified by NIST17 database. Results show that hemicelluloses and cellulose content decreased for both heat-treated woods along the treatment while lignin percentage increased. The analysis of extractives has shown several compounds normally associated to lignin thermal degradation that increased along the treatment. At the same time several compounds associated to carbohydrate thermal degradation were found in all the extracts for both heat-treated woods. These founding have allowed the understanding of the degradation pattern of wood during thermal modification. There was not much difference between afrormosia and duka woods structural compounds behaviour along thermal modification. However, the variation of the amount of extractives along the treatment depended on the species.
- Effects of the Addition of Different Additives before Mechanical Separation of Pig Slurry on Composition and Gaseous EmissionsPublication . Pereira, José L.S.; Perdigão, Adelaide; Tavares, Ana; Silva, Maria E. F.; Brás, Isabel; Ferreira Wessel, DulcineiaThe treatment of animal slurry is used to improve management on a farm scale. The aim of this laboratory study was to assess the effects of the addition of the additives biochar, alum and clinoptilolite before the mechanical separation of whole pig slurry (WS) on the characteristics and emission of NH3 , N2O, CO2 and CH4 from solid (SF) and liquid fractions (LF). The additives were mixed with WS (5% w/w), followed by separation, in a total of 12 treatments with 3 replicates, including the controls and WS with additives. Gaseous emissions were measured for 30 d by a photoacoustic multigas monitor, and initial characteristics of the slurries were assessed. The results indicated that the separation of the WS modified the initial physicochemical characteristics and increased the GWP emissions of the SF and LF, but not the NH3 losses. However, the addition of additives before separation increased the nutrient value and reduced the GWP emissions from the SF and LF. Additionally, just the additive alum was effective in the reduction of E. coli. The additives led to significant reductions in NH3 and N2O emissions, with higher reductions in NH3 losses for alum (51% for NH3 ) and similar N2O losses for all additives (70% for N2O) observed, whereas the CO2 and CH4 emissions were reduced by biochar (25% for CO2 and 50% for CH4 ) and alum (33% for CO2 and 30% for CH4 ) but not by clinoptilolite. Although the additives had a positive effect on slurry management, it can be concluded that the addition of alum before mechanical separation has the potential to be the best mitigation measure because it improves the nutrient content and sanitation and decreases gaseous losses from slurry management.
- Forest waste composting—operational management, environmental impacts, and applicationPublication . Ferreira Silva, Maria Elisabete; Saetta, Raffaella; Raimondo, Roberta; Costa, José Manuel; Ferreira, José; Brás, IsabelIn Portugal, the number of fres and the size of burnt areas are rising dramatically every year, increasing with improper management of agroforestry wastes (AFRs). This work aims to study the composting of these wastes with minimal operational costs and understand the environmental impact and the compost application on burnt soil. Thus, a study of life cycle assessment (LCA) was carried out based on windrow composting processes, considering the avoided environmental impacts associated with the end-product quality and its application as an organic amendment. Three composting piles were made with AFRs from the Residual Biomass Collection Centre (RBCC) in Bodiosa (Portugal). Sewage sludges (SS) from an urban wastewater treatment plant were used as conditioning agent. One pile with AFRs (MC) and another with AFRs and SS (MCS) were managed according to good composting practices. Another pile with the AFRs was developed without management (NMC), thus with a minimal operational cost. Periodically, it was measured several physical and chemical parameters according to standard methodologies. Eleven environmental impacts of compost production, MC and MCS, were analyzed by a LCA tool, and their efect on the growth of Pinus pinea was evaluated, using peat as reference. Composting evolution was expected for both piles. Final composts, MC and MCS, were similar, complying with organic amendment quality parameters. Compost NMC, with no operational management, showed the highest germination index. Piles MC and MCS showed similar environmental impacts, contributing to a negative impact on global warming, acidifcation, and eutrophication. Greater growth was obtained with application of MCS, followed by MC, and fnally, peat. Composting is a sustainable way to valorize AFRs wastes, producing compost that could restore burnt soils and promote plant growth and circular economy.
- Influence of Different Agro-Food Waste on Ammonia and Greenhouse Gas Emissions during CompostingPublication . Pereira, José; Costa, Telma; Figueiredo, Vítor; Marques, Francisco; Perdigão, Adelaide; Brás, Isabel; Ferreira Silva, Maria Elisabete; Ferreira Wessel, DulcineiaComposting is one of the best organic waste management techniques, with zero waste; however, it generates environmental impacts. The objective of this study was to evaluate the emission of NH3, N2O, CO2, and CH4 from the composting of olive, elderberry, and grape agro-food waste. The experiment was carried out using reactors receiving straw as control and three treatments receiving mixtures of straw and olive, elderberry, or grape wastes. The gas emissions were measured for 150 days, and the composition of the mixtures and composts was determined. The results showed NH3 and CH4 emissions were reduced by 48% and 29% by the Olive and Elderberry treatments, while only NH3 loss was reduced by 24% by the Grape treatment. Nitrous oxide, CO2, and GWP emissions were reduced by 46%, 32%, and 34% by the Olive treatment, while these losses were not reduced by the Elderberry or Grape treatments. It can be concluded olive waste can effectively reduce NH3 and GWP, while elderberry and grape wastes are also effective in reducing NH3, but not GWP. Thus, the addition of agro-food waste appears to be a promising mitigation strategy to reduce gaseous losses from the composting process.
- Carbon Footprint of Tourism Sector in Portugal Calculator DevelopmentPublication . Fernandes, Marco; Neves, Pedro; Araújo, Patrícia; Brás, Isabel; Ferreira Silva, Maria ElisabeteA carbon footprint (CF) calculator was developed to apply to a Portuguese touristic accommodation to contribute to a sustainable touristic activity. Although some calculators are available online, they are related to the country reality or use outdated emission factors. A calculator based on national emission factors is important. The calculator was developed in Microsoft Excel (version 365) and is based on the CO2e emissions resulting from electricity, water, fuels and food use, laundry and waste production. The calculator development involved: study the accommodation emission sources, selection the environmental indicators, determination of the emission factors and development of the CF formulas. Total CF calculation was made considering the partial CF per component, a monthly and annual comparison of each indicator’s emissions contribution using graphs. The emissions amount per overnight stay, per room, per area, were also assessed and these values were transformed into global hectare (gha). Avoided emissions calculation gives the information about the efforts in CF reduction, and two indicators were considered: electricity production from renewable energy sources and the amount of separated waste for recycling. It was considered reforestation measures to achieve carbon neutrality. This calculator incorporates four components not often used: water, laundry, waste, food, and avoided emissions.
- Valorisation of Forest and Agriculture Residual Biomass—The Application of Life Cycle Assessment to Analyse Composting, Mulching, and Energetic Valorisation StrategiesPublication . Brás, Isabel; Ferreira Silva, Maria Elisabete; Raimondo, Roberta; Saetta, Raffaella; Mignano, Vincenzo; Fabbricino, Massimiliano; Ferreira, JoséThe treatment of agricultural and forest residues (AFRs) has become an important issue nowadays, both to avoid improper management and for their enhancement. In the study area of Viseu (Portugal), the AFRs are taken to a Residual Biomass Collection Centre. These are valorised in a Biomass Power Plant to produce electricity. Two further processes could be implemented to valorise this biomass: mulching and composting. This study aims to understand the best strategy to enhance this type of biomass residual considering their environmental performance. The Life Cycle Assessment (LCA) was applied considering a cradle-to-grave approach. Different processes of all the technologies were analysed, and the data collected enabled a comparison of 11 environmental impact categories. The results show that composting is the best alternative, except for global warming and ozone layer depletion, and energy valorisation has the greatest impact on five of the considered categories. In the three processes, impacts are mainly associated with the production and shredding phases of the residual biomass, rather than the transportation stages, due to the short distances covered. In all cases, the value of the final product generates market consequences in terms of electricity and fertiliser production. In line with the aim of the study, its outcomes may provide scientific support to local decision makers in defining best practices in the management of the AFRs.
- A Cradle-to-Grave Life Cycle Assessment Study on a New Countertop MaterialPublication . Silva, Luiza; Silva, Maria; Brás, Isabel; Domingos, Idalina; Ferreira Wessel, Dulcineia; Ferreira, JoséThe life cycle of furniture products has been decreased in the last years as a consequence of the continuous improvement of people’s housing conditions. This behavior increases the waste amount in an urban area. The focus of this study was developing a Life Cycle Assessment (LCA) (cradle-to-grave) of a new countertop product. Two scenarios for countertop waste management were proposed, one considering landfilling and another considering recycling. The functional unit chosen was 1 m2 of finished panel (countertop) and the boundary system involved the study of raw materials, product packaging, the panel production process, the installation process, the panel use, and its end of life. The chosen method for impact assessment was EPD (2018) available in the SimaPro PhD software. The results showed that recycling has a positive effect on the environmental impacts, with the variation ranging from 0.3% on Abiotic Depletion (FF) to 15.9% on Eutrophication. A comparison between the product studied and products with similar functions was also conducted and although this product was not the worst performer, it has a lot of room for improvement.
- Avaliação de impacte ambiental da gestão de resíduos da produção de uma bancada com base na abordagem de ACVPublication . Silva, Luiza; Ferreira Silva, Maria Elisabete; Brás, Isabel; Domingos, Idalina; Ferreira Wessel, Dulcineia; Ferreira, JoséIntroduction: Consumerism has led to an increase in environmental problems, and for this reason, sustainable solutions must be the priority when designing new products or services. Life Cycle Assessment (LCA) is one of the most important analytical tools available for choosing the best decision when it comes to sustainability. Objective: The focus of this study was to apply an LCA to the management of wastes from a kitchen/bathroom countertop production. The waste management scenarios studied were landfill (current practice) and waste recycling. The panel consists of a ceramic layer on a lamellar panel substrate, formed by glassliner and PVC, which is intended to be resistant to water, scratches and impacts. The residues generated from the panel production are glassliner and PVC plastics and ceramics. Methods: The LCA methodology was followed and the EPD 2018 method available in the SimaPro software was chosen to quantify the environmental impacts of waste management. The environmental impact categories studied were eutrophication, global warming, photochemical oxidation, ozone layer depletion, abiotic depletion and acidification. Results: The results showed that the two plastic wastes are the main contributors to acidification, eutrophication and global warming. However, for photochemical oxidation and water scarcity, the ceramic component residue is the main contributor. Comparing the two scenarios, waste recycling reduces the impacts in all environmental impact categories, in comparison with landfill. Conclusion: Recycling the residues from the production of panels brings improvements in environmental impacts in all categories analyzed.