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The food industry requires new production models that include more environmentally friendly waste management practices, considering that the environmental loads of solid waste and wastewater associated with this sector cause damage to the receiving ecosystems. The approach considered in this study focuses on the design and environmental assessment of an enzymatic process for the valorization of ferulic acid present in the effluent of a corn tortilla plant. The ferulic acid can be immobilized on chitosan so that the ferulic acid grafted chitosan can be used as a bioactive film with enhanced antioxidant properties with potential applications in the biotechnology sector. Its real projection approach requires the evaluation of its environmental and economic performance, trying to identify its benefits and potential in the value chain, using the Techno-Economic Analysis (TEA) as a phase for the conceptual design of the process and the Life Cycle Assessment (LCA) methodology for the environmental evaluation. It should be noted that the TEA indicators are promising, since the values of the financial indicators obtained are representative of the economic profitability, which makes the ferulic acid valorization a viable process. In terms of the environmental impact of the process, the buffer dose and the chitosan production process are identified as the main critical points. This double benefit in environmental and economic terms shows that the valorization of ferulic acid for chitosan functionalization is a promising alternative to improve the sustainability performance of corn processing.
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Quitosana , Ácidos Cumáricos , Zea mays , Quitosana/química , Ácidos Cumáricos/química , Polímeros/química , Gerenciamento de Resíduos/métodosRESUMO
The textile industry is one of the most chemical-intensive processes, resulting in the unquestionable pollution of more than a quarter of the planet's water bodies. The high recalcitrant properties of some these pollutants resulted on the development of treatment technologies looking at the larger removal efficiencies, due to conventional systems are not able to completely remove them in their effluents. However, safeguarding the environment also implies taking into account indirect pollution from the use of chemicals and energy during treatment. On the other hand, the emerged technologies need to be economically attractive for investors and treatment managers. Therefore, the costs should be kept under control. For this reason, the present study focuses on a comparative Life Cycle Assessment and Life Cycle Costing of four scale-up scenarios aiming at mono and di-azo reactive dyes removal from textile wastewater. Two reactors (sequencing batch reactor and two-phase partitioning) were compared for different reaction environments (i.e., single anaerobic and sequential anaerobic-aerobic) and conditions (different pH, organic loading rates and use of polymer). In accordance with the results of each scenario, it was found that the three technical parameters leading to a change in the environmental profiles were the removal efficiency of the dyes, the type of dye eliminated, and the pollutant influent concentration. The limitation of increasing organic loading rates related to the biomass inhibition could be overcame through the use of a novel two-phased partitioning bioreactor. The use of a polymer at this type of system may help restore the technical performance (84.5 %), reducing the toxic effects of effluents and consequently decreasing the environmental impact. In terms of environmental impact, this is resulting into a reduction of the toxic effects of textile effluents in surface and marine waters compared to the homologous anaerobic-aerobic treatment in a sequencing batch reactor. However, the benefits achieved for the nature comes with an economic burden related to the consumption of the polymer. It is expected that the cost of investment of the treatment with the two-phase partitioning bioreactor rises 0.6-8.3 %, depending on market prices, compared to the other analyzed sequential anaerobic-aerobic technologies. On the other side, energy and chemical consumption did not prove to be limiting factors for economic feasibility.
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Águas Residuárias , Poluentes Químicos da Água , Humanos , Corantes , Compostos Azo , Polímeros , Reatores Biológicos , Têxteis , Eliminação de Resíduos Líquidos/métodosRESUMO
Biomass is one of the renewable resources with the greatest potential, not only because of the possibility of energy recovery but also because of its content in components of interest. In this context, the regions of Galicia and Portugal have large areas of land dedicated to forestry, agriculture and livestock, and the large amount of waste generated represents a cost for the producer. The importance of these facts has aroused great interest in society to focus its interest on improving the current situation while seeking a benefit, both environmental and economic, from existing resources. That is why the integration of biotechnological processes and biorefinery for their valorization are considered key aspects in the way of producing bioproducts and bioenergy. This research article proposes a process for producing resveratrol from whey from the dairy industry and eucalyptus residues from forestry exploitation. In order to evaluate its suitability, a techno-economic analysis and an environmental assessment have been carried out using the Life Cycle Assessment (LCA) methodology. The results obtained show the potential of these scenarios both from the economic point of view, by obtaining a minimum sale price of resveratrol to ensure the viability of the process below the market average, and from the environmental point of view, being eucalyptus residues those that result in a lower contribution to the environment per unit of resveratrol produced. Future research should focus on increasing the throughput of the production process to increase its profitability and on reducing energy requirements throughout the process, as these have been the main critical points identified. In addition, following the sensitivity assessment, it has been concluded that opting for renewable energy is the most sustainable option.
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Eucalyptus , Soro do Leite , Resveratrol , Energia Renovável , Agricultura , BiomassaRESUMO
Wheat plays an essential role in safeguarding global food security. However, its intensive agricultural production, aimed at maximizing crop yields and associated economic benefits, jeopardizes many ecosystem services and the economic stability of farmers. Rotations with leguminous are recognized as a promising strategy in favor of sustainable agriculture. However, not all crop rotations are suitable for promoting sustainability and their implications on agricultural soil and crop quality should be carefully analyzed. This research aims to demonstrate the environmental and economic benefits of introducing chickpea into a wheat-based system under Mediterranean pedo-climatic conditions. For this purpose, the crop rotation "wheat-chickpea" was evaluated and compared with the conventional regime (wheat monoculture) by means of life cycle assessment methodology. For this purpose, inventory data (e.g., agrochemical doses, machinery, energy consumption, production yield, among others) was compiled for each crop and cropping system, thus converted into environmental impacts based on two functional units: 1 ha per year and one of gross margin. Eleven environmental indicators were analyzed, including soil quality and biodiversity loss. Results indicate that chickpea-wheat rotation system offers lower environmental impacts, regardless of the functional unit considered. Global warming (18 %) and freshwater ecotoxicity (20 %) were the categories with the largest reductions. Furthermore, a remarkable increase (96 %) in gross margin was observed with the rotation system, due to the low cost of chickpea cultivation and its higher market price. Nevertheless, proper fertilizer management remains essential to fully attain the environmental benefits of crop rotation with legumes.
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Cicer , Fabaceae , Ecossistema , Triticum , Produtos Agrícolas , Agricultura/métodos , Solo , Biodiversidade , Produção AgrícolaRESUMO
Soil plays an essential role as a habitat, source of nutrients and support for vegetation. Promoting food security and environmental sustainability of agricultural systems requires an integrated approach to soil fertility management. Agricultural activities should be developed with preventive approaches aimed at avoiding or reducing negative impacts on the soil physicochemical and biological properties and the depletion of soil nutrient reserves. In this regard, Egypt has developed the Sustainable Agricultural Development Strategy to encourage environmentally friendly practices among farmers, such as crop rotation and water management, in addition to extending agriculture to desert areas, favoring the socio-economic development of the region. In order to evaluate the outcomes of the plan beyond quantitative data of production, yield, consumption and emissions, the environmental profile of agriculture in Egypt has been assessed under a life-cycle perspective in order to identify the associated environmental burdens and ultimately contribute to improving the sustainability policies of agricultural activity within the framework of a crop rotation system. In particular, a two-year crop rotation (Egyptian clover-maize-wheat) was analyzed in two distinct agricultural areas in Egypt: New Lands in desert regions and Old Lands along the Nile River, traditionally recognized as fertile areas due to the river alluvium and water availability. The New Lands had the worst environmental profile for all impact categories, except for Soil organic carbon deficit and Global potential species loss. Irrigation and on-field emissions associated with mineral fertilization were identified as the most critical hotspots of Egyptian agriculture. In addition, land occupation and land transformation were reported as the main drivers of biodiversity loss and soil degradation, respectively. Beyond these results, further research on biodiversity and soil quality indicators is needed to more accurately assess the environmental damage caused by the conversion of deserts into agricultural areas, given the species richness these regions hold.
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Carbono , Solo , Solo/química , Egito , Agricultura/métodos , EcossistemaRESUMO
Crop rotation represents a potentially sustainable strategy to address environmental problems of intensive agricultural practices, such as soil degradation, biodiversity reduction, and greenhouse gas emissions. This manuscript assesses the environmental and economic implications of introducing lupin cultivation into winter wheat-based rotation systems under an organic regime in Galicia, Spain. Life Cycle Assessment methodology was used to determine the environmental impacts of three rotation systems over a six-year period: lupin â wheat â rapeseed (OA1), lupin â potato â wheat (OA2), and lupin â wheat â rapeseed â maize (OA3). For a robust assessment, three functional units were applied: land management (ha), economic indicator (gross margin in euros) and protein content (1 kg of protein-corrected grain). Moreover, the environmental profiles were compared with rotation systems without lupin crop in a conventional regime. In terms of Global Warming, impacts of about 2214, 3119 and 766 kg CO2eq·ha-1 were obtained for OA1, OA2 and OA3, respectively. Moreover, OA1 is the best rotation in terms of land and protein. Meanwhile, OA2 rotation is the best choice in the economic function, as it obtained the highest level of gross margin (5708 ·ha-1). Furthermore, with the exception of acidification, organic systems are less impactful than conventional systems. Ammonia emissions from the use of manure are the reason for these higher impacts. Organic rotations OA1 and OA2 have about 6 % or 15 % less gross margin than their conventional counterparts, respectively, however, an increase of 28 % was obtained for rotation OA3. This study helps decision-makers to implement environmentally and economically viable strategies.
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Gases de Efeito Estufa , Lupinus , Agricultura/métodos , Fertilizantes , Solo , Espanha , TriticumRESUMO
Crop diversification, as a sustainable land management practice, is a potential strategy to face soil degradation, climate change and food security, being the incorporation of legumes in cereal rotation systems, a strategy that improves soil nutrient levels. In a context of sustainable agriculture, this manuscript aims to evaluate the effect of lupin cultivation from an environmental and economic perspective in Galician winter wheat-based rotation systems. The life cycle analysis (LCA) methodology was applied for three rotation systems over a six-year period: lupin + wheat + oilseed rape (RA1), lupin + potato + wheat (RA2), and lupin + wheat + oilseed rape + maize (RA3). The general approach of this study was to collect primary data associated with the rotation crops to quantify their environmental impacts and economic benefits and to identify their advantages or disadvantages. Comparing and contrasting the environmental profiles based on three functional units: hectare land (ha), financial indicator (gross margin, ) and yield production (kg of wheat grain) allows a robust evaluation of each crop rotation system. Relating to rotations without lupin, the results indicate that for the impact categories evaluated, the introduction of lupin proved to be favourable with notable reductions of 64% and 30% in the environmental categories of Global Warming and Marine Eutrophication, respectively. Moreover, favourable economic consequences were evident in rotations RA1 and RA2 with a 19% and 51% increase in financial indicators, respectively, but with a marginal reduction of 2% in gross margin in RA3. This study motivates stakeholders to understand the environmental impacts of diversification strategies in agricultural systems and serves as a baseline to address the assessment of the social aspects of these systems for a complete sustainability perspective.
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Lupinus , Triticum , Agricultura/métodos , Produtos Agrícolas/metabolismo , Grão Comestível , Solo , EspanhaRESUMO
This study performs the environmental assessment of itaconic acid (IA) production from wheat straw. The Life Cycle Assessment (LCA) methodology is used to determine the environmental hotspots, considering impact categories such as Global Warming (GW), Fossil Resource Scarcity (FRS), Water Consumption (WC), among others. A sensitivity analysis was performed considering an optimization of the steam explosion process and 100% renewable energy. Results report an impact of about 14.33 kg CO2 eq in GW, 4.15 kg of oil eq in FRS, for each kg of IA produced for the baseline scenario. Moreover, the pretreatment and fermentation stages constitute hotspots of the IA production. In addition, using a renewable energy source in production would reduce the impact by 82% in GW, 71% in PM and 82% in FRS categories. The optimization of the steam explosion process presents a better performance in GW and FRS but also lies in an increase in WC.
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Succinatos , Triticum , Fermentação , VaporRESUMO
The sustainable production of poly(lactic acid) (PLA) or poly(butylene succinate) (PBS) from corn glucose syrup, corn stover and sugar beet pulp (SBP) have been assessed via process design, preliminary techno-economic evaluation, life cycle assessment and life cycle costing (LCC). Cost-competitive PLA and PBS production can be achieved in a SBP-based biorefinery, including separation of crude pectin-rich extract as co-product, leading to minimum selling prices of $1.14/kgPLA and $1.37/kgPBS. Acidification Potential, Eutrophication Potential and Human Toxicity Potential are lower when SBP is used. The LCC of PLA ($1.42/kgPLA) and PBS ($1.72/kgPBS) production from SBP are lower than biaxial oriented polypropylene (BOPP, $1.66/kg) and general purpose polystyrene (GPPS, $2.04/kg) at pectin-rich extract market prices of $3/kg and $4/kg, respectively. Techno-economic risk assessment via Monte-Carlo simulations showed that PLA and PBS could be produced from SBP at the market prices of BOPP ($1.4/kg) and GPPS ($1.72/kg) with 100% probability to achieve a positive Net Present Value at pectin-rich extract market prices of $3/kg and $4/kg, respectively. This study demonstrated that SBP-based biorefinery development ensures sustainable production of PLA and PBS as compared to fossil-derived counterparts and single product bioprocesses using glucose syrup and corn stover.
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Estágios do Ciclo de Vida , Poliésteres , Animais , Butileno Glicóis , Humanos , Polímeros , Medição de RiscoRESUMO
Challenges associated with the sustainability of the water cycle pose new opportunities for resource recovery and greater environmental protection. While centralized wastewater treatment plants must evolve in their design and operation to adapt to a scenario of increasing demand for water, resources and energy, the decentralized approach emerges as an option to be considered in small communities or developing residential areas where bioenergy production can be improved through the recovery of organic matter in segregated streams or where the investment in the sewer network for connection to a centralized facility may be technologically or economically unfeasible. The main objective of this work is to evaluate the environmental and economic profile of a hybrid-decentralized configuration for the purpose of efficient wastewater management and resource recovery and its comparative evaluation with the centralized treatment scenario. Beyond water reclamation, decentralized treatment offers the possibility of valorization of digestate streams as nutrient sources for horticultural or ornamental crops in the vicinity of the plant. Based on the results of the environmental profile, this manuscript shows that the decentralized treatment approach is in line with the philosophy and guidelines of the circular economy, as it allows the use of reclaimed water and biofertilizers under safe and environmental-friendly conditions.
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Conservação dos Recursos Naturais , Purificação da Água , Simbiose , Eliminação de Resíduos Líquidos , Águas Residuárias , ÁguaRESUMO
The sustainable and continued production of enough food to feed the entire world's population is one of the main concerns in the food industry. Spain, and in particular Galicia, which is an eminently fishing region characterised by the consumption of large quantities of fish, both fresh and processed, must face the challenge of shifting its seafood productive fabric towards a circular economy. To achieve this objective, the first task is to demonstrate that circular economy principles allow to reduce the environmental impacts associated with seafood production. In this sense, this study proposes the environmental evaluation of the skipjack tuna (Katsuwonus pelamis) value chain within a canning industry located in Galicia through the LCA methodology from an attributional perspective, including the valorisation processes for biowaste (edible and inedible by-products). Results indicate that the main crucial subsystems of the value chain are tuna fishing and the canning process, as it was expected considering other similar studies on seafood products. Moreover, this specific case study demonstrates that the multi-product strategy applied to the canning sector is environmentally viable. Thus, although the environmental impacts of the entire system are increased by including further valorisation operations, the environmental loads assigned to the main product (canned tuna) decrease compared to the one-product system by assigning environmental burdens to other value-added products (tuna pâté, fishmeal, and fish oil).
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Indústria Alimentícia , Atum , Animais , Meio Ambiente , Alimentos Marinhos , EspanhaRESUMO
Menus served at public services can be considered as a good opportunity for consumers to demand a service that ensures healthy and environmentally friendly food. It is especially in the sector of nurseries and schools, where these demands make the most sense since they call for the protection of particularly vulnerable population: children. The purpose of this study is to analyze the biweekly menus served at a public Spanish nursery canteen considering the link with the two most recognized environmental indicators: the consumptive water footprint (WF) and the carbon footprint (CF). The WF and CF of the menus vary considerably between menus (619-1359 L·menu-1 and 0.75-2.95 kg CO2eq·menu-1). The assessment has identified non-dairy sources of protein and dairy-based products as the key food categories in all menus. Menus with more meat (mostly beef) and dairy products (mainly cheese) were associated with higher impacts. That is, the average impact of menus with beef is about 2 times greater than the one of all other menus. The distribution and cooking stages presented negligible contributions in terms of greenhouse gases emissions, mainly due to the consumption of local/regional products and low-energy intensive cooking techniques. The most important strategy for reducing environmental impacts is based on reducing the frequency of consumption of beef, so that poultry and lean pork are consumed alternately. This reduction should not compromise the necessary protein intake for toddlers. Attention should also be paid to afternoon snacks that are rich in cold meat and dairy products. Considering these issues, significant reductions in WF and CF indicators could be achieved, up to 550 L·menu-1 and 0.70 kg CO2eq·menu-1. Since eating habits introduced at an early stage are more likely to develop into adult behaviour, children canteen services are an excellent opportunity to promote healthy eating habits in children and their families.
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Pegada de Carbono , Dieta , Animais , Bovinos , Comportamento Alimentar , Carne , Instituições AcadêmicasRESUMO
In recent years, there has been a great movement towards the generation of knowledge related to the biorefinery concept. First-generation biorefineries bear the stigma of using arable land and edible crops for fuel instead of as sources of food and feed. However, second-generation biorefineries have not reached the level of full technical feasibility. Bearing in mind the objective of sugar production from sugar, starch, or lignocellulosic raw materials, the purpose of this study is to assess the environmental impact of first- and second-generation biorefineries, considering as an example for the comparative evaluation, the production of sugar fractions from crops (starch and sugar crops), and lignocellulosic biomass (hardwood and softwood). The characterization results were obtained using the ReCiPe 1.1 model, implemented through the SimaPro 9.0 software. Both production systems are inherently different and have strengths and weaknesses that must be carefully analyzed. The resulting environmental profile shows that the silviculture of wood contributes less to the environmental impact than cropping activities in most impact categories. In general, this study suggests that first-generation systems are burdened environmentally by the use of fertilizers, which have a significant impact on categories such as marine and freshwater eutrophication and terrestrial acidification, while second-generation systems are limited by the intensive processing steps needed for delignification, typically involving the use of chemicals and/or energy. LCA in early stages of the production of bio-based building blocks, rather than on the manufacture of biofuels or bioplastics, allows the precise identification of the environmental burdens that may be influencing the overall environmental profile of a biorefinery.
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Biocombustíveis , Açúcares , Animais , Biomassa , Produtos Agrícolas , Estágios do Ciclo de VidaRESUMO
Dietary patterns are influenced by numerous external factors such as cultural taste and customs, nutritional and economic aspects and lifestyle and consumer preferences. Otherwise, food also causes a great impact on the environment and there can be a large difference between choosing certain foodstuffs, such as plant or animal-based ones. The key for an environmentally friendly and healthy diet is the high consumption of plant-based products, low amounts of animal-origin foodstuffs and limited quantity of refined grains, processed food and added sugars. Nevertheless, adherence to it has been decreasing over the years due to the adoption of a more westernized consumption pattern. Thus, the main goal of this study is to monitor the food consumption pattern at household level during a period of 10 years (2008-2017), selecting Spain as case study. Both the impacts that foodstuffs included in the food basket cause in the environment, and the socio-economic variables that influence the consumer choice are considered. Results show a generalized decrease of the carbon footprint over the years. However, it does not always mean an approach to a healthier diet, considering that in this case it decreases both the consumption of those foods with a greater environmental footprint as those essential for a balanced diet with low ecological impact. Additionally, there is also an increase in the consumption of processed food, which further distances the dietary pattern from the recommendations, what can be more pronounced for the most vulnerable population groups, with less purchasing power to access healthy food.
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Life cycle assessment (LCA) has been widely applied in many different sectors, but the marine products and seafood segment have received relatively little attention in the past. In recent decades, global fish production experienced sustained growth and peaked at about 179 million tonnes in 2018. Consequently, increased interest in the environmental implications of fishery products along the supply chain, namely from capture to end of life, was recently experienced by society, industry and policy-makers. This timely review aims to describe the current framework of LCA and its application to the seafood sector that mainly focused on fish extraction and processing, but it also encompassed the remaining stages. An excess of 60 studies conducted over the last decade, along with some additional publications, were comprehensively reviewed; these focused on the main LCA methodological choices, including but not limited to, functional unit, system boundaries allocation methods and environmental indicators. The review identifies key recommendations on the progression of LCA for this increasingly important sustaining seafood sector. Specifically, these recommendations include (i) the need for specific indicators for fish-related activities, (ii) the target species and their geographical origin, (iii) knowledge and technology transfer and, (iv) the application and implementation of key recommendations from LCA research that will improve the accuracy of LCA models in this sector. Furthermore, the review comprises a section addressing previous and current challenges of the seafood sector. Wastewater treatment, ghost fishing or climate change, are also the objects of discussion together with advocating support for the water-energy-food nexus as a valuable tool to minimize environmental negativities and to frame successful synergies.
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Mudança Climática , Alimentos Marinhos , Animais , Estágios do Ciclo de VidaRESUMO
Currently, most of the greenhouse gas (GHG) emissions are attributed to cities, as they are the global centers of business, residential and cultural activity, cities are expected to play a leading role in proposing climate change mitigation actions. To do so, it is important to have tools that allow the carbon footprint of cities to be assessed as accurately as possible. This study aims to quantify the carbon footprint (CF) associated with the activities developed in a Spanish city (Cadiz, Southwest Spain) by means of two available environmental methodologies, namely Environmentally Extended Input-Output Analysis (EEIOA) and Life Cycle assessment (LCA). When EEIOA is considered, two downscaling factors were proposed for the analysis due to the nature of the data handled (monetary data), based on the incomes (DF1) and expenditures (DF2) per inhabitant at city level. Regarding LCA, the rates of consumption of goods and production of waste per inhabitant have been processed to estimate the CF. The CF scores identified were 5.25 and 3.83 tCO2-eq·inhabitant-1·year-1 for DF1 and DF2 respectively, according to EEIOA, and 5.43 tCO2-eq·inhabitant-1·year-1, considering LCA. Therefore, a similarity can be concluded between the results obtained with both methodologies despite the inherent differences. Considering the results, the downscaling procedure based on income per inhabitant should be preferred, pointing to EEIOA as a good alternative to LCA for evaluating the CF at city level, requiring less time and effort. In contrast, EEIOA reports more limitations when critical flows were identified, which LCA can solve. Finally, this study can be of great interest to policy makers and city governments to know the CF and the main flows that contribute and in this way, can develop new policies and city models for reducing GHG emission new policies and city models for reducing GHG emission and addressing climate change.
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The wood panel industry requires the introduction of more environmental-friendly adhesives due to the strict current regulations on formaldehyde-based emissions. The purpose of this study was to environmentally analyse the production of four different bio-adhesives as alternatives to the most conventional fossil resins used in the production of wood panels. The bio-adhesives proposed for analysis derived from different available renewable biopolymers such as protein (soy) and lignin (Kraft and Organosolv), as well as tannin. The production systems were evaluated from a cradle-to-gate perspective using the Life Cycle Assessment methodology, with the aim of identifying critical parameters and comparing them with fossil substitutes. Inventory data of bio-adhesives were modelled at large scale from lab scale experiments and completed with literature reports. Our results showed that the soy-based and tannin based bio-adhesive had an overall better profile than fossil resins, identifying the production of polyacrylamide for the former, and the production of condensed tannin and glyoxal for the latter, as the main environmental hotspots. In contrast, further research is required on the use of lignins, specifically because of the electricity requirements in the lignin glyoxalation stage (a process required for the functionalization of lignin). Sensitivity analyses were conduced on these key parameters suggesting that there is room for improvement.This study provides useful information for researchers and policy-makers on where to focus their activities with the aim of making the future of bio-adhesives more technically and environmentally favourable.
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Adesivos , Madeira , Formaldeído , Indústrias , LigninaRESUMO
The retrofitting of wastewater treatment plants (WWTPs) should be addressed under sustainability criteria. It is well known that there are two elements that most penalize wastewater treatment: (i) energy requirements and (ii) sludge management. New technologies should reduce both of these drawbacks to address technical efficiency, carbon neutrality and reduced economic costs. In this context, the main objective of this work was to evaluate two real plants of different size in which major modifications were considered: enhanced recovery of organic matter (OM) in the primary treatment and partial-anammox nitrification process in the secondary treatment. Plant-wide modelling provided an estimate of the input and output flows of each process unit as well as the diagnosis of the main performance indicators, which served as a basis for the calculation of environmental and economic indicators using the LCA methodology. The combination of high-rate activated sludge (HRAS) + partial nitrification Anammox can decrease the environmental impacts by about 70% in the climate change (CC) category and 50% in the eutrophication potential (EP) category. Moreover, costs can be reduced by 35-45% depending on the size of the plant. In addition, the enhanced rotating belt filter (ERBF) can also improve the environmental profile, but to a lesser extent than the previous scenario, only up to 10% for CC and 15% for EP. These positive results are only possible considering the production of energy through biogas valorization according to the waste-to-energy scheme.
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Esgotos , Águas Residuárias , Biocombustíveis , Nitrificação , Eliminação de Resíduos LíquidosRESUMO
Composting is a solid waste management alternative that avoids the emission of methane associated with its disposal in landfill and reduces or eliminates the need for chemical fertilisers if compost is applied. The main objective of this study was to analyse the environmental burdens of composting as a way to achieve a more circular valorisation of wine waste. To do so, with the purpose of identifying optimal operational conditions and determining the "hotspots" of the process, the life cycle assessment (LCA) methodology was used. The consumption of diesel fuel in machinery was determined to be the main critical point in the environmental effects of the system, followed by the transport and distribution of the compost. After the application of compost instead of mineral fertilisers, corn, tomato and strawberry crops would have a better environmental performance in most impact categories. In this sense, a maximum improvement of 65% in terrestrial ecotoxicity is achieved in strawberry cultivation. In light of the results obtained, it is demonstrated that composting is a suitable way of organic waste valorisation according to Circular Economy principles.
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Compostagem , Eliminação de Resíduos , Gerenciamento de Resíduos , Grão Comestível , Frutas , Solo , Resíduos SólidosRESUMO
For millennia, bread and wheat have been one of the most important sources of nutrients in many civilizations. Today, mechanization and evolution in agriculture and food processing have intensified yields and modified the biological and nutritional aspects of multiple crops and foods. The Galician bread is a reference value of food heritage in Spain, which is made from common wheat grain and is a mixture of indigenous Galician wheat and conventional Spanish wheat. In the pursuit of product excellence, it is interesting to identify the environmental profile as support criteria in decision-making, not only to analyse product environmental sustainability, but also as a marketing element to improve consumer awareness. The paper has a twofold perspective to analyse the environmental burdens of wheat cultivation and the bread sector, using life cycle assessment approach: 1) the comparison of the different types of agricultural systems, i.e. the cultivation of Galician wheat following a strategy of monoculture and crop rotation, certified Galician seed production and its comparison with conventional wheat cultivation and 2) the environmental profile of Galician bread. The functional units chosen were 1 kg of wheat grain transported to the milling facility and 1 kg of Galician bread. The results show that wheat cultivation presents the main environmental impacts of bread production, mainly due to the use of agrochemicals and field emissions. The best cultivation scenario corresponds to a crop rotation system, since chemical fertilisation is not applied. In comparative terms with many staple foods produced in Europe, Galician bread has a low environmental impact. The overall environmental results of bread production draw attention to the dependence of bread and flour manufacturers on the agricultural sector, highlighting the need to share responsibilities across the supply chain. In addition, this study contributes to the stakeholder debate on environmental impacts related to food heritage.