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1.
Water Res ; 266: 122350, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39217644

RESUMO

Urban water systems in China are facing multiple challenges, including rapid urbanisation, climate change and infrastructure ageing. It is crucial to evaluate their environmental performance from a holistic perspective in planning and management processes. To the best of our knowledge, there is a lack of nationwide life cycle assessment (LCA) studies on China's urban water systems that cover all system stages. Therefore, this study aims to present a comprehensive and nationwide LCA analysis that pinpoints the environmental hotspots and their major sources across China. This study was conducted based on water utility databases at the province level, covering water abstraction and treatment, waterwork sludge treatment, water distribution, sewage collection, stormwater drainage, wastewater treatment and sewage sludge treatment. Nine environmental impact categories were calculated and analysed. The results reveal the inequity of environmental impacts across provinces, with overall impacts geographically higher in the east and south, lower in the west and north. However, at the functional unit level, the impacts in the northern and northeastern provinces are higher than other regions. Most environmental categories are dominated by multiple water system stages. The analyses of underlying drivers found that purchased electricity is the primary source of several environmental impacts. This study provides a holistic understanding of the environmental performance of China's urban water systems, offers some insights for comprehensive decision-making support on sustainable water system management, and can also serve as a benchmark for future scenario analysis to explore options for reducing environmental impact.

2.
ChemSusChem ; : e202401702, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39221509

RESUMO

Carbon dots (CDs) are fluorescent carbon-based nanomaterials with remarkable properties, making them more attractive than traditional fluorophores. Consequently, researchers focused on their development and application in fields such as sensing and bioimaging. One potential advantage of employing CDs is using organic waste as carbon precursors in their synthesis, providing a pathway for waste upcycling for a circular economy. However, waste-based CDs often have low fluorescence quantum yields (QYFL), limiting their practical applications. So, there is a need for a well-defined strategy to consistently produce waste-based CDs with appreciable QYFL, irrespective of the starting waste material. Herein, we developed a fabrication strategy based on the hydrothermal treatment of waste materials, using citric acid as a co-carbon precursor and ethylenediamine as N-dopant. This strategy was tested with various materials, including corn stover, spent coffee grounds, cork powder, and sawdust. The results showed consistently appreciable QYFL, reaching up to ~40%. A Life Cycle Assessment (LCA) study demonstrated that producing these waste-based CDs has lower environmental impacts compared to CDs made solely from commercial reagents. Thus, we have established a framework for the environmentally friendly production of CDs by upcycling different waste materials without significant sacrifices in performance (QYFL).

3.
J Environ Manage ; 369: 122363, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39232323

RESUMO

Green roof systems have been developed to improve the environmental, economic, and social aspects of sustainability. Selecting the appropriate version of the green roof composition plays an important role in the life cycle assessment of a green roof. In this study, 10 compositions of an intensive green roof for moderate zone and 4 green roof compositions for different climatic conditions were designed and comprehensively assessed in terms of their environmental and economic impacts within the "Cradle-to-Cradle" system boundary. The assessment was carried out over a 50-year period for a moderate climate zone. The results showed that asphalt strips and concrete slab produced the highest total emissions. It was found that most greenhouse gases emissions were released in the operational energy consumption phase and in the production phase. The energy consumption phase (48.78%) for automatic irrigation and maintenance caused the highest Global Warming Potential (GWP) value (758.39 kg CO2e) in the worst variant, which also caused the highest life cycle cost (878.47€). On the contrary, in the best variant, planting more vegetation and lower maintenance and irrigation requirements led to a reduction in GWP (445.0 kg CO2e), but in terms of cost (506.6€) this composition didn't represent the best variant. The Global Warming Potential Biogenic (GWP-bio) compared to the Global Warming Potential Total (GWP-total) represents a proportion ranging from 0.8% to 78% depending on the proposed vegetation. Overall higher biogenic carbon values (up to 1525 kg CO2e) were observed for the proposed tall vegetation of Magnolia, Red Mulberry, Hawthorne, Cherry, and Crab-apple Tree. Based on the results of the multicriteria analysis, which included core environmental & economic parameters, biogenic carbon emission levels, the outcome of this paper proposed optimal green roof composition. Optimal intensive green roof composition was subjected to a sensitivity analysis to determine the impact of changing climatic conditions on CO2 emissions and life cycle costs. The results of the sensitivity analysis show that the optimal variant of the green roof can be implemented in the cold and subtropical zone with regard to CO2 emissions, but not with regard to life cycle costs.

4.
Waste Manag ; 189: 314-324, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39226845

RESUMO

This study presents a comprehensive analysis of greenhouse gas (GHG) emissions associated with waste transfer and transport, incorporating derived leachate treatment-a factor often overlooked in existing research. Employing an integration model of life cycle assessment and a vehicle routing problem (VRP) methods, we evaluated the GHG reduction potential of waste transfer and transport system. Two Chinese counties with different topographies and demographics were selected, yielding 80 scenarios that factored in waste source separation as well as vehicle capacity, energy sources, and routes. The functional unit (FU) is transferring and transporting 1 tonne waste and treating derived leachate. The GHG emissions varied from 12 to 39 kg CO2 equivalent per FU. Waste source separation emerged as the most impactful mitigation strategy, not only for the studied system but for an integrated waste management system. Followings are the use of larger capacity vehicles and electrification of the vehicles. These insights are instrumental for policymakers and stakeholders in optimizing waste management systems to reduce GHG emissions.

5.
Health Serv Insights ; 17: 11786329241271562, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39139395

RESUMO

Background: Healthcare is responsible for 4% to 10% of carbon emissions worldwide, of which 22% is related to transport. Telemedicine emerged as a potential solution to reduce the footprint, for example, by reducing travel. However, a need to understand which variables to include in carbon footprint estimations in telemedicine limits our understanding of the beneficial impact telemedicine might have on our environment. This paper aims to systematically assess the reported carbon footprint and include variables assessed by the literature, comparing telemedicine with usual care. Methods: The systematic review followed the PRISMA guidelines in PubMed, Medline, Embase and Scopus. A quality assessment was performed using a transparency checklist for carbon footprint calculators. Carbon emissions were evaluated based on four categories, including patient travel, and streamlined life cycle assessment (LCA) for assessing included variables relevant to telemedicine. Results: We included 33 articles from 1117 records for analysis. The average transparency score was 38% (range 18%-68%). The median roundtrip travel distance for each patient was 131 km (interquartile range [IQR]: 60.8-351), or 25.6 kgCO2 (IQR: 10.6-105.6) emissions. There is high variance among included variables. Saved emissions are structurally underestimated by not including external factors such as a streamlined LCA. Conclusions: Telemedicine aids in reducing emissions, with travel distance being the most significant contributor. Additionally, we recommend accounting for the LCA since it highlights important nuances. This review furthers the debate on assessing carbon footprint savings due to telemedicine.

6.
Water Environ Res ; 96(8): e11098, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39138812

RESUMO

Complete retention lagoons with wastewater reuse for agricultural purposes may offer sustainability advantages over alternative systems for small communities in semiarid regions. This study quantifies the environmental life cycle impact of adopting agriculture water reuse systems using case study data to estimate operating and building infrastructure impacts and spatial-temporal modeling to quantify resource trade-offs. Water reuse system benefits are highly dependent on supply-storage-demand dynamics. The relative size of irrigated agricultural land to the lagoon size was the most significant factor influencing site water application rates. The benefits are sensitive to changes in air emissions occurring from the agricultural land and further emphasize the importance of proper fertilizer management when adopting water reuse systems. Wastewater reuse from complete retention lagoons reduce life cycle GHG emissions, primarily through excavation reductions, offset fertilizer use, and especially from increased crop yields from wastewater reuse at previously rainfed sites. PRACTITIONER POINTS: Seven case studies and spatial-temporal modeling quantified resource trade-offs for water reuse to reduce lagoon size. Excavation reductions and offset fertilizer compensated for emissions from electricity and construction. Crop yield increases were the largest environmental benefit of adopting water reuse. System benefits are highly dependent on supply-storage-demand dynamics. Designers should use climatic data to help estimate potential variability in available water for reuse and associated energy and crop production.


Assuntos
Modelos Teóricos , Águas Residuárias , Eliminação de Resíduos Líquidos/métodos , Agricultura/métodos , Reciclagem , Conservação dos Recursos Naturais/métodos
7.
Chemosphere ; 363: 142991, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39094705

RESUMO

The conversion of biomass to bioenergy is one of the approaches to creating a sustainable society. In this study, the life cycle assessment and the net energy analysis of converting mixed sewage sludge and beverage waste into bioenergy via a combined hydrothermal liquefaction-anaerobic digestion (HTL-AD) system was carried out. Primary sludge (PS), winery rose lees (RL), brewery Trub (BT), the mixture of brewery trub and primary sludge (BTPS) and the mixture of winery rose lees and primary sludge (RLPS) were the feedstocks considered. Efficient energy utilization [in form of net energy ratio (NER)], and environmental emissions were evaluated. The NER of BT (2.07) and RL (1.76) increased when mixed with PS (3.18) to produce BTPS (3.20) and RLPS (2.85). Also, the HTL phase of the combined HTL-AD system produced a greater NER than the AD phase in BT, BTPS, and PS and vice-versa in RL and RLPS. Six environmental impact categories were studied namely global warming, terrestrial acidification, ionizing radiation, terrestrial ecotoxicity, human carcinogenic toxicity, and human non-carcinogenic toxicity. RL produced the greatest environmental impact while BTPS produced the least impact, thus indicating the advantage of feedstock combination. This study shows that the combination of feedstocks for bioenergy production in an HTL-AD system does not only increase the quality and quantity of products but also increases the overall NER as well as reducting the environmental impacts. The study also proved that an integrated HTL-AD system is an energy efficient system with greater resource utilization and less environmental footprint than the constituent systems.


Assuntos
Esgotos , Esgotos/química , Anaerobiose , Bebidas , Biocombustíveis , Biomassa , Eliminação de Resíduos Líquidos/métodos
8.
Animals (Basel) ; 14(15)2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39123728

RESUMO

Today, one of the major challenges of dairy farmers is to reduce their environmental footprint to establish more effective, efficient, and sustainable production systems. Feed additives such as yeast probiotics could potentially allow them to achieve these objectives through the improvement of milk production, feed efficiency, and ration valorization, hence mitigating the environmental impacts of milk production. In this study, the life cycle assessment (LCA) principle was performed to estimate the environmental impact of the production and supplementation of a commercial yeast probiotic (Actisaf Sc 47) in three trials performed in three different countries that are representative for around 50% of the milk production in Europe: France (French trial), United Kingdom (UK trial), and Germany (German trial). For each trial, two groups of animals were compared: control, without Actisaf Sc 47 supplementation, used as baseline; and experimental, with Actisaf Sc 47 supplementation at 5 or 10 g/cow/day. Different impact categories were analyzed for each group to calculate the impact of producing 1 kg of fat- and protein-corrected milk. An initial analysis was done only during the period of Actisaf Sc 47 supplementation and showed than the supplementation with Actisaf Sc 47 reduced, on average by 5%, the carbon footprint during the three trials. A second analysis was done via the extrapolation of all the data of each trial to an annual farm level, including the lactation period (305 days), dry period (60 days), and the period with and without Actisaf Sc 47 supplementation. Reported at a farm annual scale, the average reduction allowed by Actisaf Sc 47 supplementation was 2.9, 2.05, 2.47, 1.67, 2.28, 2.18, 2.14, and 2.28% of the carbon footprint, land use, water use, resource use, acidification, freshwater eutrophication, marine eutrophication, and terrestrial eutrophication, respectively. On average, the production of 1 kg of fat- and protein-corrected milk by using Actisaf Sc 47 was shown to improve environmental impacts compared to control. Regarding Actisaf Sc 47 production, the LCA showed that the production of 1 kg of Actisaf Sc 47 emitted 2.1 kg CO2 eq with a negligible contribution to total the carbon footprint of milk ranging from 0.005 to 0.016%. The use of Actisaf Sc 47 in dairy cows could then result in different positive outcomes: improving performance and efficiency while reducing the global carbon footprint.

9.
Polymers (Basel) ; 16(15)2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39125128

RESUMO

Contaminated sediments may induce long-term risks to humans and ecosystems due to the accumulation of priority and emerging inorganic and organic pollutants having toxic and bio-accumulation properties that could become a secondary pollution source. This study focused on the screening of novel bio-based materials to be used in the decontamination of marine sediments considering technical and environmental criteria. It aimed to compare the environmental impacts of cellulose-based adsorbents produced at lab scale by using different syntheses protocols that involved cellulose functionalization by oxidation and branching, followed by structuring of an aerogel-like material via Soxhlet extraction and freeze-drying or their combination. As model pollutants, we used 4-nitrobenzaldehyde, 4-nitrophenol, methylene blue, and two heavy metals, i.e., cadmium and chromium. When comparing the three materials obtained by only employing the Soxhlet extractor with different solvents (without freeze-dying), it was observed that the material obtained with methanol did not have a good structure and was rigid and more compact than the others. A Life Cycle Assessment (LCA) was conducted to evaluate the environmental performance of the novel materials. Apart from the hierarchical categorization of the materials based on their technical and environmental performance in eliminating organic pollutants and heavy metal ions, it was demonstrated that the cellulose-based material obtained via Soxhlet extraction with ethanol was a better choice, since it had lower environmental impacts and highest adsorption capacity for the model pollutants. LCA is a useful tool to optimize the sustainability of sorbent materials alongside lab-scale experiments and confirms that the right direction to produce new performant and sustainable adsorbent materials involves not only choosing wastes as starting materials, but also optimizing the consumption of electricity used for the production processes. The main results also highlight the need for precise data in LCA studies based on lab-scale processes and the potential for small-scale optimization to reduce the environmental impacts.

10.
Anaesth Crit Care Pain Med ; : 101420, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39089450

RESUMO

INTRODUCTION: Single-use bronchoscopes have replaced reusable ones in many institutions. This study aimed to evaluate the environmental and financial impacts of both strategies: reusable and single-use bronchoscopes. MATERIAL AND METHODS: We conducted a pragmatic study in a 21-bed polyvalent ICU, in Saint-Brieuc, Bretagne, France. The eco-audit consisted of estimating greenhouse gas (GHG) emissions, considering the life cycle of each strategy. Greenhouse gas (GHG) emissions related to construction, packaging, transport and waste elimination were compared between 2 devices: the reusable bronchoscope, a Pentax® FI-16RBS that was disinfected twice daily; and the single-use bronchoscope, the bronchoflex agile® from TSC. RESULTS: For the reusable bronchoscope, GHG emissions were marginally impacted by the number of bronchoscopies performed (from 185 kg eq.CO2 per year to 192 kg eq.CO2 for 10 or 110 bronchoscopies per year). For the reusable device, GHG emissions directly depended on the number of bronchoscopies performed with 3.82 kg eq.CO2 emitted per bronchoscopy. The breakeven point for the reusable bronchoscope was estimated at 50 bronchoscopies in terms of GHG emissions and 96 bronchoscopies for financial considerations. CONCLUSION: Considering current practice in our ICU, reusable bronchoscopes have lower GHG emissions when used more than 50 times a year and a lower cost when used more than 96 times a year as compared with single-use bronchoscopes.

11.
ChemSusChem ; : e202401239, 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39180254

RESUMO

There is currently a great need for rigid, high-performance and processable bio-based polymers and plastics as alternatives to the fossil-based materials used today. Here, we report on the straightforward synthesis and polymerization of lignin-derived methacrylate monomers based on the methyl esters of syringic, vanillic, and 4-hydroxybenzoic acid, respectively. The corresponding homopolymethacrylates exhibit high glass transition temperatures (Tgs) at 106, 128, and 197 °C, respectively. Rheological properties and thermal stability up to at least 277 °C indicate that these polymers are melt-processable. In addition, copolymers with methyl methacrylate are prepared to further vary and tune the polymer properties. An integrated ex-ante and prospective life-cycle assessment of key environmental impact parameters indicates similar or only slightly higher values compared to well-established fossil-based methyl methacrylate. Moreover, the toxicity towards human HeLa cell lines compares well with that of poly(methyl methacrylate). Hence, the potential availability of lignin-derived acids, combined with the straightforward and potentially upscalable monomer synthesis, make these rigid polymers appealing alternatives towards bio-based high-Tg thermoplastic materials with low toxicity.

12.
Meat Sci ; 217: 109627, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39141968

RESUMO

Pork belly is a meat cut valued for its rich flavour and texture, attributed to its high fat content, which also makes it susceptible to oxidation. Therefore, meat producers and processors must carefully select packaging options to maximise shelf life while meeting consumer preferences. This study aimed to develop customised packaging strategies for sliced pork belly with varying fat content to extend shelf life while minimizing environmental impact. The research compared three packaging solutions: modified atmosphere packaging (MAP1: 70:30% O2:CO2, MAP2: 30:40:30% O2:CO2:N2) and vacuum skin packaging (VSP) for pork bellies with low (LF: 16.07 ± 1.87%), medium (MF: 37.39 ± 4.41%), and high fat content (HF: 57.57 ± 2.36%). Samples packaged in VSP exhibited the longest shelf life (13-14 days) with lower purge and reduced fat and colour oxidation compared to MAP-packaged samples for all studied belly types. Nonetheless, the impact of MAP on shelf life depended on the belly type. HF bellies, with lower proportions of unsaturated fatty acids, showed less purge, and greater colour and fat stability, resulting in a longer shelf life compared to LF and MF bellies. LF and MF bellies in MAP2 showed the shortest shelf life (around 6 days), followed by LF and MF in MAP1 (around 7-8 days). Life Cycle Assessment indicated VSP generally as the most environmentally favourable option for LF and MF bellies, whereas for HF bellies, the choice among the three packaging solutions depended on the specific impact category under consideration.


Assuntos
Embalagem de Alimentos , Armazenamento de Alimentos , Embalagem de Alimentos/métodos , Animais , Suínos , Armazenamento de Alimentos/métodos , Cor , Vácuo , Gorduras na Dieta/análise , Oxirredução , Carne de Porco/análise , Meio Ambiente
13.
Sci Total Environ ; 951: 175452, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39134264

RESUMO

Annually, 8.3 million tonnes of mismanaged plastic waste enter oceans, prompting the food packaging industry, a major contributor, to minimize its environmental footprint. Within the seafood sector, a nascent number of studies are exploring the impacts of various packaging solutions for distribution, yet clear insights remain elusive. This study tries to fill the gap by comparing the impacts of two seafood packaging options: disposable expandable polystyrene (EPS) boxes and, for the first time, reusable plastic crates (RPC) crafted from high-density polyethylene. Using the life cycle assessment methodology with a 'cradle to grave' approach, the research evaluates the distribution of 1260,000 t of fish from port of Vigo (Spain) to various markets. Similar climate change values emerge in local (5.00·107 kg CO2 eq.) and regional trade (1.20·108 kg CO2 eq.) for both options, but RPCs exhibit around a 12 % increase (6.15·108 kg CO2 eq.) during national distribution, emphasizing package weight and load significance. The findings across all impact categories exhibited general consistent trends. The sensitivity analysis suggests relocating washing facilities to port could enhance RPCs´ environmental benefits for transport within a 160 km range. These findings underscore reusable packaging's potential as an eco-friendlier alternative in specific contexts, aligning with heightened environmental concerns and regulatory pressures surrounding plastic usage.

14.
Sci Total Environ ; 949: 175035, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39089380

RESUMO

The significant grasslands of Europe and its member states represents a significant feedstock opportunity for circular bioeconomy development. The development of green biorefineries (GBR), to supply protein for the feed industry from grass, could help many European member states to address significant deficits in protein availability and reduce imports. The current study assesses the environmental footprint of alternative GBR protein extraction techniques from grasses and legumes using life cycle assessment. The focus is on comparing feedstock and technology pathways that could displace soya bean imports. The study finds that leaf protein concentrate (LPC) produced from grass had an improved environmental performance when compared to soya bean meal (SBM), across the assessed feedstock (perennial ryegrass or grass-clover mixtures) and technology pathways (one-stage maceration versus multi-stage maceration). For example, in the case of Climate Change the emission intensity for LPC was 57-85 % lower per tonne of crude protein (CP) compared with SBM. Acidification burdens were 54-88 % lower, and Eutrophication: Freshwater burdens were 74-89 % lower. Some scenarios of GBR produced LPC with a larger Energy Resources: Non-Renewable burden than SBM, though this could be mitigated with higher renewable energy (biogas and wind energy) integration within the scenario. Grass-clover scenarios generally achieved a lower intensity of emissions compared to ryegrass scenarios, particularly in the category of Climate Change, where feedstock cultivation represented a significant contributor to impacts. Overall, GBR can produce high quality protein with a lower environmental burden than SBM, but choice of feedstock and system design are critical factors for overall environmental performance.


Assuntos
Fabaceae , Poaceae , Proteínas de Plantas , Mudança Climática
15.
Sci Total Environ ; 949: 175223, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39097018

RESUMO

The fishing sector constitutes an important source of economic revenue in northern Spain. In this context, various research studies have focused on the application of the five-step Life Cycle Assessment (LCA) and Data Envelopment Analysis (DEA) methodology to quantify environmental impacts of fishing systems. However, some of them have used environmental indicators that focus on individual environmental issues, hindering the goal of achieving integrated resource management. Therefore, in this study, the Water-Energy-Food (WEF) Nexus is employed as an integrative perspective that considers the synergies and trade-offs between carbon footprint, energy requirements, and water demand. The main objective of this study is to evaluate the operational efficiency and environmental impacts of Cantabrian fishing fleets. To this end, the combined use of LCA and DEA, along with the WEF Nexus, was applied to the Cantabrian purse seine fleet. DEA matrices were generated using the LCA-derived WEF nexus values as inputs to calculate efficiency scores for each vessel. Subsequently, based on the efficiency projections provided by the DEA model, a new impact assessment was performed to understand the eco-efficiency and potential environmental benefits of operating at higher levels of efficiency within this fleet. The average efficiency of the fleet was above 60 %. Inefficient units demonstrated a greater potential to reduce their environmental impacts (up to 65 %) by operating according to efficiency projections. Furthermore, the results revealed a strong dependence of environmental impacts on one of the operational inputs, i.e., fuel consumption. These findings highlight the significance of embracing holistic approaches that combine technical, economic, and social factors to achieve a sustainable balance in fisheries systems. In this regard, the five-step LCA + DEA method applied in conjunction with the WEF Nexus emerged as a suitable tool for measuring operational and environmental objectives.


Assuntos
Pesqueiros , Espanha , Conservação dos Recursos Naturais/métodos , Monitoramento Ambiental/métodos , Pegada de Carbono , Meio Ambiente
16.
Sci Total Environ ; 951: 175448, 2024 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-39137840

RESUMO

Biochar application is an effective strategy to address Agro-climatic challenges. However, the agro-environmental impacts of different biochar technology models are lacking of systematic summaries and reviews. Therefore, this paper comprehensively reviews recent developments derived from published literature, delving into the economic implications and environmental benefits of three distinct process namely technologies-pyrolysis, gasification, and hydrothermal carbonization. This paper specifically focuses on the agricultural life cycle assessment (LCA) methodology, and the influence of biochar preparation technologies and products on energy consumption and agricultural carbon emissions. LCA analysis shows that process and feedstock pose a predominant role on the properties and production rate of biochar, while gasification technology exhibits excellent economic attributes compared to the other two technologies. Biochar applications in agricultural has the beneficial effect of sequestering carbon and reducing emissions, especially in the area of mitigating the carbon footprint of farmland. However, the complexity of the composition of the prepared feedstock and the mismatch between the biochar properties and the application scenarios are considered as potential sources of risks. Notably, mechanism of carbon sequestration and emission reduction by soil microorganisms and agro-environmental sequestration by biochar application remains unclear, calling for in-depth studies. We review novel aspects that have not been covered by previous reviews by comparing the technical, economic, and environmental benefits of pyrolysis, gasification, and hydrothermal carbonization systematically. Overall, this study will provide a valuable framework to environmental implications of biochar preparation, application, and life cycle assessments.

17.
J Environ Manage ; 367: 122015, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39102783

RESUMO

In response to global challenges in resource supply, many industries are adopting the principles of the Circular Economy (CE) to improve their resource acquisition strategies. This paper introduces an innovative approach to address the environmental impact of waste Glass Fiber Reinforced-Polymer (GFRP) pipes and panels by repurposing them to manufacture structural components for new bicycle and pedestrian bridges. The study covers the entire process, including conceptualization, analysis, design, and testing of a deck system, with a focus on the manufacturing process for a 7-m-long prototype bridge. The study shows promising results in the concept of a sandwich structure utilizing discarded GFRP pipes and panels, which has the flexibility to account for variabilities in dimensions of incoming products while still meeting mechanical requirements. The LCA analysis shows that the transportation of materials is the governing contributing factor. It was concluded that further development of this concept should be accompanied by a business model that considers the importance of the contributions from the whole value chain.


Assuntos
Polímeros , Polímeros/química , Reciclagem , Pedestres , Meios de Transporte , Vidro/química
18.
J Environ Radioact ; 278: 107510, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39088873

RESUMO

The Irish Sea and the Baltic Sea are nowadays still the two most Cs-137 contaminated Seas worldwide. However, the origins of this contaminations are completely different. While the Baltic Sea was unintentionally contaminated due to global fallout after the accident in the Chernobyl nuclear powerplant in 1986, the Irish sea was intentionally used for low level liquid radioactive waste discharges from the Sellafield nuclear reprocessing facility (called Windscale until 1981) between the 1950s and 1990s. Nowadays, more than 30 years later, it is still possible to detect these contaminations in fish, water and sediments of both seas. Since fish are an important part of the human diet, monitoring Cs-137 levels in fish is essential for assessing the potential radiation exposure to humans. In 2019 and 2020 two surveys were dedicated to study the current levels of radioactive contamination in fish species from both Seas. During both surveys, fish samples were collected and analysed by gamma spectrometry later on. The results show that the average Cs-137 activity in benthic, demersal and pelagic fish species from the Baltic Sea are 2.7, 4.6 and 4.2, respectively, times higher than the corresponding values of the Irish Sea. Based on this and two other comparisons, it is concluded that the Baltic Sea is the most contaminated with Cs-137.


Assuntos
Radioisótopos de Césio , Peixes , Monitoramento de Radiação , Poluentes Radioativos da Água , Poluentes Radioativos da Água/análise , Monitoramento de Radiação/métodos , Radioisótopos de Césio/análise , Animais , Oceanos e Mares
19.
Sci Total Environ ; 951: 175408, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39128521

RESUMO

Construction and demolition waste (C&DW) represents a pressing concern within the European Union, underscoring the urgent need for effective waste management strategies. The selection of these solutions constitutes a complex task, entailing the identification of efficient C&DW management strategies that balance appropriate practices, regulatory compliance, resource conservation, economic feasibility, and environmental considerations. LCA is widely utilized to assess environmental impact, yet the economic aspect has not been adequately incorporated into the LCA process in the field of C&DW management. The life cycle costing (LCC) methodology has been tailored to assess economic performance in conjunction with LCA. The selection of an appropriate multi-criteria decision-making (MCDM) method is vital for the C&DW system. This study proposes a novel framework for C&DW management by integrating LCA and LCC outcomes into MCDM, using AHP for weight determination, and applying TOPSIS to identify the favorable alternative. Four waste management alternatives were examined in the Lombardy region of Italy, namely (i) landfill; (ii) recycling for concrete production and road construction, incineration with energy recovery; (iii) recycling for road construction; (iv) recycling for concrete production and road construction. We determine that, with the implementation of various scenarios, the most suitable scenario emerges to be recycled for concrete production and road construction, with a score of 0.711/1; recycling for road construction with final score 0.291/1, ranks second; recycling for concrete production and road construction, incineration with energy recovery scores 0.002/1, ranks third; and landfill (scores: 0/1) is the worst choice, signifying it has the highest environmental impacts and the least economic benefits. Lastly, recommendations were formulated to enhance the environmental performance of the system.

20.
Sci Total Environ ; 950: 175189, 2024 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-39097021

RESUMO

This research analyses 24 years of oil extraction in blocks 16 and 67 of the Yasuní National Park (YNP) in the Amazonian Forest of Ecuador, one of the most biodiverse spaces in the world and with the current presence of ancient indigenous communities. As a novel contribution, we have carried out a Life-Cycle Assessment (LCA) that quantifies the footprints associated with the extraction, transportation, refining, distribution and final uses of the oil in four different scenarios (oil for asphalt use, electricity, marine fuel and passenger car transport). This study also sheds light on the energy return at the point of use of different oil-derivatives, and complements this with a qualitative analysis of the social, cultural and environmental implications for the Waorani communities. We conclude that the environmental burdens of the extraction process in blocks 16 and 67 in 2015 were greater than those of countries such as the United States, Saudi Arabia and Indonesia, based on the analysis of 11 impact categories. The blocks' operation is the most unfavourable for the categories of Terrestrial Acidification Potential (TAP), Global Warming Potential (GWP), Terrestrial Ecotoxicity Potential (TEP) and Ecosystem Quality Loss Potential (EQL), with increments of 804.15 %, 105.36 %, 506.29 % and 210.73 %, respectively, in relation to the average of the rest of the extraction systems analysed. Specifically, the present case study shows 75.18 % higher impacts in the blocks addressed, when compared to the Ecuadorian average. During the period 1999-2022, the carbon emissions associated with the oil extraction in these blocks have increased by 139.01%. It has been detected a neo-colonial economic behaviour: while the Ecuadorian state received 21% of the sales, the Spanish government and the oil companies received, on average, 38% and 41% of the per-litre average fuel price, respectively. Thus, 79% of the income stayed in the Global North. We conclude that, on average, 19.64 % of the impacts associated with crude oil production and consumption occur in the Amazonian region of the YNP, depending on the fuel used and the consumption mechanism. For the Global Warming Potential (GWP) impact category, the extraction process carries, on average, 34.51 % of the weight in all of the life-cycle impacts, depending on the consumption scenario. It was also estimated that to be able to use 0.33 kWh of electricity from fuel combustion, 0.47 kWh of energy for goods transport and 0.20 kWh for passenger transport, an investment of 1 kWh is required, with an average extended EROI of 1:3.33. According to the qualitative analysis performed, it has been concluded that the main local impacts are related to the obstacles in environmental monitoring and information, the economic dependence of the communities on the oil extraction company, and cultural transformations; impacts that are not easily quantifiable or detectable using other methodologies. The combination of the qualitative analysis and LCA showed that the neo-colonial economic distribution did not compensate the social and environmental impacts of the oil extraction occurred in the YNP.

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