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1.
Environ Monit Assess ; 196(8): 704, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38967806

RESUMO

This study compares different powertrains of sport utility vehicles (SUVs) with respect to ambient temperature and energy mix in Slovakia using the well-to-wheel (WTW) Life Cycle Assessment (LCA) method. Battery electric vehicles (BEV), plug-in hybrid electric vehicles (PHEV), and petrol and diesel vehicles were assessed and compared. The WTW study was conducted in SimaPro software assessing electricity/petrol/diesel production, transport, and use (energy conversion in the vehicle), with impact categories being climate change, particulates, NOx emissions, ionizing radiation, and fossil resource scarcity depending on the season (summer and winter). The results indicate that for Slovak conditions, BEV generally had the lowest environmental impact in both seasons studied. The only exceptions were ionizing radiation, which is clearly caused by the high share of nuclear power in the Slovak energy mix, and NOx emissions, which are caused by the combustion of biomass for electricity generation. The other impact categories were dominated by vehicles with an internal combustion engine. The results of emissions from fuel production are also given for each impact category. The transportation of fuel did not exceed the value of 1% for any impact category or for any powertrain. The conclusions of the study support the global trend in favour of vehicle electrification as an important way to reduce the negative environmental impacts of internal combustion engine vehicles in Slovakia.


Assuntos
Poluentes Atmosféricos , Monitoramento Ambiental , Temperatura , Emissões de Veículos , Eslováquia , Monitoramento Ambiental/métodos , Poluentes Atmosféricos/análise , Emissões de Veículos/análise , Poluição do Ar/estatística & dados numéricos , Meio Ambiente , Mudança Climática , Fontes de Energia Elétrica
2.
Environ Sci Technol ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953529

RESUMO

Waste-to-energy systems can provide a functional demonstration of the economic and environmental benefits of circularity, innovation, and reimagining existing systems. This study offers a robust quantification of the greenhouse gas (GHG) emission reduction potential of the adoption of anaerobic digestion (AD) technology on applicable large-scale dairy farms in the contiguous United States. GHG reduction estimates were developed through a robust life cycle modeling framework paired with sensitivity and uncertainty analyses. Twenty dairy configurations were modeled to capture important differences in housing and manure management practices, applicable AD technologies, regional climates, storage cleanout schedules, and methods of land application. Monte Carlo results for the 90% confidence interval illustrate the potential for AD adoption to reduce GHG emissions from the large-scale dairy industry by 2.45-3.52 MMT of CO2-eq per year considering biogas use only in renewable natural gas programs and as much as 4.53-6.46 MMT of CO2-eq per year with combined heat and power as an additional biogas use case. At the farm level, AD technology may reduce GHG emissions from manure management systems by 58.1-79.8% depending on the region. Discussion focuses on regional differences in GHG emissions from manure management strategies and the challenges and opportunities surrounding AD adoption.

3.
Chimia (Aarau) ; 78(6): 397-402, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38946412

RESUMO

Nanomaterials hold immense potential for numerous applications in energy, health care, and environmental sectors, playing an important role in our daily lives. Their utilization spans from improving energy efficiency to enhancing medical diagnostics, and mitigating environmental pollution, thus presenting a multifaceted approach towards achieving sustainability goals. To ensure the sustainable and safe utilization of nanomaterials, a thorough evaluation of potential hazards and risks is essential throughout their lifecycle-from resource extraction and production to use and disposal. In this review, we focus on understanding and addressing potential environmental and health risks associated with nanomaterial utilization. We advocate for a balanced approach with early hazard identification, safe-by-design principles, and life cycle assessments, while emphasizing safe handling and disposal practices, collaboration, and continuous improvement. Our goal is to ensure responsible nanotechnology development, fostering innovation alongside environmental and community well-being, through a holistic approach integrating science, ethics, and proactive risk assessment.


Assuntos
Nanoestruturas , Medição de Risco , Humanos , Poluição Ambiental/prevenção & controle , Nanotecnologia/métodos
4.
Sci Total Environ ; : 174474, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38964407

RESUMO

The current demand for composites reinforced with renewable fibers is greater than it has ever been. In comparison to glass fibers, natural fibers yield the advantages of lesser density and cost. Although comparable specific properties exist between glass and natural fibers, the latter shows lower strength. However, with the copper coating and chemical treatment of natural fibers, the strength of the composites can be increased nowadays. The current research investigation focuses on the life cycle assessment of the raw, chemically treated, and copper coated fiber reinforced bagasse and banana composites to compare the emissions on the environment of these samples to prove their applicability. The study includes all the processes, from the extraction of fibers to the formation of composites, i.e., from cradle to gate, and detailed inventory. The ReCiPe H midpoint method has been utilized in SimaPro software to quantify the emissions. The results indicate that the maximum global warming emission is due to the energy consumption used during the manufacturing of these composites. Electricity contribution for chemically treated and copper coated composites in global warming contribution is slightly greater than that of raw composites i.e., 73.275 % in C- BG/P, 73.06 % in Cu- BG/P, 73.65 % in C- BN/P and 74.28 % in Cu- BN/P which is comparatively higher than 63.8 % in R- BG/P and 64.97 % in R- BN/P. The next major contributions come from polylactic acid for all the three samples of bagasse fiber reinforced PLA composite and banana fiber reinforced PLA composite. The raw samples also show improved fiber strength compared to chemical and copper coated samples.

5.
Environ Sci Technol ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953238

RESUMO

Sewage sludge, as a carbon-rich byproduct of wastewater treatment, holds significant untapped potential as a renewable resource. Upcycling this troublesome waste stream represents great promise in addressing global escalating energy demands through its wide practice of biochemical recovery concurrently. Here, we propose a biotechnological concept to gain value-added liquid bioproducts from sewage sludge in a self-sufficient manner by directly transforming sludge into medium-chain fatty acids (MCFAs). Our findings suggest that yeast, a cheap and readily available commercial powder, would involve ethanol-type fermentation in chain elongation to achieve abundant MCFA production from sewage sludge using electron donors (i.e., ethanol) and acceptors (i.e., short-chain fatty acids) produced in situ. The enhanced abundance and transcriptional activity of genes related to key enzymes, such as butyryl-CoA dehydrogenase and alcohol dehydrogenase, affirm the robust capacity for the self-sustained production of MCFAs. This is indicative of an effective metabolic network established between yeast and anaerobic microorganisms within this innovative sludge fermentation framework. Furthermore, life cycle assessment and techno-economic analysis evidence the sustainability and economic competitiveness of this biotechnological strategy. Overall, this work provides insights into sewage sludge upgrading independent of additional carbon input, which can be applied in existing anaerobic sludge fermentation infrastructure as well as to develop new applications in a diverse range of industries.

6.
Artigo em Inglês | MEDLINE | ID: mdl-38926307

RESUMO

Diversifying energy sources and managing waste biomass are two pressing contemporary issues. The new technology proposed in this study aims to address both by converting waste biomass into energy and fertilizer through the use of a biofuel cell (BFC). The purpose of this study is to assess the environmental impacts associated with this innovative technology through a Life Cycle Assessment (LCA). To achieve the goal, the production and use of the cell were modelled, considering both laboratory-scale operations and industrial-scale approximations. The study explored alternative scenarios, such as sensitivity analyses involving different acids and bases, renewable energy sources, and heat recovery. Comparisons with conventional biomass waste treatments (anaerobic digestion and composting) demonstrated that the BFC technology remains competitive. To further improve the BFC's environmental footprint, efforts should focus on reducing energy requirements and enhancing nutrient recovery during scale-up. These insights are crucial for advancing sustainable waste treatment technologies and maximizing the potential of discarded biomass in an environmentally friendly manner.

7.
Waste Manag ; 186: 236-248, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38941734

RESUMO

Proper management of wastewater treatment plant side streams in pulp and paper mills is a matter of great interest. This study evaluates the environmental impact of different strategies in the management of biosludge from pulp and paper mills in Finland through a Life Cycle Assessment methodology. The base industrial standard practice, biosludge incineration for energy recovery and ash landfill disposal (Scenario 1), was compared to the alternative process of hydrothermal carbonization. The hydrochar generated from hydrothermal carbonization was evaluated for energy recovery through incineration (Scenario 2), or for use in composting for nutrient recovery (Scenario 3). The results showed that the hydrothermal process improved the overall environmental performance of the sludge management, particularly in terms of energy consumption and greenhouse gas emissions. The use of hydrochar as a soil amendment in composting also resulted in a significant reduction on the environmental impact compared to the other two scenarios. Overall, this study highlights the potential of hydrothermal carbonization and hydrochar utilization as sustainable options for managing biosludge from pulp mills.

8.
Animals (Basel) ; 14(12)2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38929344

RESUMO

An estimate of the environmental impact of dairy farms in Northern Italy producing milk for hard cheese (protected designation of origin) has been obtained through a comprehensive life cycle assessment. The estimate focused on climate change (CC) and photochemical ozone creation potential (POCP) indicators, which were evaluated according to the Intergovernmental Panel on Climate Change (IPCC) guidelines and interpreted with the aid of the feeds' composition evaluated using near-infrared reflectance spectroscopy (Foss NIR-System 5000) as well as with a diet evaluation according to the NRC (National Research Council) or the CNCPS (Cornell Net Carbohydrate and Protein System) nutrient requirement modeling. Herds were classified into high-, mid-, and low-performing based on the daily milk yield per cow. A lower impact on indicators was observed as herd performance increased. The high-performing herds had a lower contribution from enteric fermentation (6.30 × 10-1 kgCO2-eq), and the more milk that they produced allowed for a differentiation of CC from land use and transformation (2.39 × 10-1 kgCO2-eq), compared to low-performing herds (3.66 × 10-1 kgCO2-eq). Compared to the IPCC approach, the CC and POCP indicator estimates were reduced when addressing the feed's quality, particularly in mid- and high-performing herds. The results could be helpful in the dairy sector as they provide an insight into how diet quality affects the environmental impact of milk.

9.
Bioengineering (Basel) ; 11(6)2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38927790

RESUMO

Farm leftovers, particularly crop residues, are a key source of renewable energy in Canada. The nation's robust agricultural industry provides ample biomass, derived from forestry and agriculture resources, for energy generation. Crop residues, such as straws and husks, play a crucial role in this biomass reservoir, contributing to biofuel production and greenhouse gas mitigation efforts. Focusing on supply chains, waste management, and emission reduction, this study evaluates the sustainability of wheat straw, an agricultural biomass by-product. The environmental issues of various approaches to managing agricultural biomass were explored. Following an evaluation of biomass features, conversion methods, and economic and environmental advantages, the results show anaerobic digestion to be the most sustainable approach. Four metrics were examined in relation to social elements, and numerous aspects were considered as inputs in the evaluation of transportation costs. The use of electric trucks versus fuel-based trucks resulted in an 18% reduction in total operating costs and a 58% reduction in consumption costs. This study examined CO2 emissions over four different transportation distances. The data indicate that a significant reduction of 36% in kg CO2 equivalent emissions occurred when the distance was lowered from 100 km to 25 km. These findings offer insights for creating practical plans that should increase the sustainability of agricultural biomass leftovers.

10.
Sci Total Environ ; 944: 173945, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-38876346

RESUMO

Rare earth elements are crucial for the development of cutting-edge technologies in various sectors, such as energy, transportation, and health care. Traditional extraction of rare earth elements from soil and ore deposits primarily involves chemical leaching and solvent extraction. Environmental-based biological rare earth element extraction, such as bioleaching, can be a promising alternative to mitigate pollution and hazardous wastes. We investigated the sustainability aspects (techno-economic and environmental impact) of mixed rare earth metals production from soil in Idaho, USA. We focused on the bioleaching of surface soil using techno-economic analysis and "cradle-to-gate" life cycle assessment. The system boundary included collection, transportation, bioleaching, and molten salt electrolysis. Our results revealed that the mixed rare earth metals (including Nd, Ce, and La) production costs approximately $10,851 per metric ton and generates 1.9 × 106 kg CO2 eq./ton. Our results showed that most emissions are due to energy consumption during bioleaching. Over a 100-year time horizon ultrasound-assisted bioleaching can reduce greenhouse gas emissions by approximately 91 % compared to the traditional bioleaching process by decreasing the organic acid leaching process time and energy consumption. Our work demonstrates that higher solids loading in leaching with biological reactions can promote economic feasibility and reduce chemical wastes.

11.
Surgeon ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38918114

RESUMO

BACKGROUND AND PURPOSE: Healthcare is responsible for 5.4% of greenhouse gas emissions in the UK. Emissions in surgery is a relatively unexplored area; in particular, this hasn't yet been looked at as a whole in ENT in the UK. The purpose of the study was to quantify the amount of greenhouse gas (GHG) emission from a tonsillectomy and assess the proportion of each source's contribution. METHODS: Operational data from tonsillectomies performed at a large university teaching hospital in the UK were gathered and converted to global warming potential using established conversion factors and data from existing healthcare-focused carbon footprint studies. The domains considered were waste, pharmaceuticals, surgical instrument decontamination, transportation, consumables use and utilities. This study used a process-based carbon footprint approach based on the "Greenhouse Gas Protocol: Product Life Cycle Accounting and Reporting Standard". MAIN FINDINGS: The carbon footprint of a typical case was 41 kgCO2e which is equivalent to driving a car for approximately 150 miles. Consumables were responsible for 17% of this; 14% came from transport, 5.4% from decontamination, 4.8% from pharmaceuticals and 4% from waste. However, the largest GHG was from utilities, of which heating, ventilation and air conditioning was the overwhelming contributor. CONCLUSIONS: While the largest sources of GHG emissions require hospital-wide initiatives, there are aspects of consumables and waste streams we can improve on in ENT surgery. These include the use of disposable vs reusable instruments as well as increased availability and use of recycling waste streams in theatres. Additionally, this study provides a template that can be applied to other ENT procedures.

12.
Environ Manage ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38935143

RESUMO

Food production is known to have significant environmental impacts, with the main contributors residing in the farming and transportation life cycle phases. Of the various food products transported around the world, avocados have increasingly gained attention as a high-commodity superfood. Avocados require specific climatic and agricultural conditions for farming, with the most fertile land and conditions located outside Europe. Consequently, most avocados consumed in Europe are imported over vast geographical distances, with little information available to quantify the environmental impacts of this imported superfood. This paper aims to present the most detailed life cycle assessment results of an avocado cultivated, grown and harvested in the Limpopo Province of South Africa and exported to the European market for sale and consumption. A life cycle assessment was developed for the farming, harvesting, handling, packaging, ripening, transportation, and carbon sequestration potential of the avocado, and it was used to conduct a holistic life cycle assessment. Input data was obtained through an 18-month data collection campaign across the relevant stakeholders. A baseline 'business-as-usual' scenario is focused on throughout this study, and scope for optimisation is identified for each life cycle phase where applicable, accompanied by uncertainty analyses. Results show a total carbon input of 904.85 kg CO2e/tonne. Mitigating this, 521.88 kg CO2e/tonne is offset, resulting in a net carbon footprint of 382.97 kg CO2e/tonne with uncertainty ranges of -23.22 to +58.69 kg CO2e/tonne, normalised to 57.45 g CO2e/avocado grown in South Africa and sold in Europe. The environmental impacts of the avocado industry under consideration are largely mitigated by the "nature first" philosophy of the farming and logistics enterprises, which have made significant investments in reducing emissions. Sensitivity analyses indicate that implementing large-scale renewable energy, using alternative packaging instead of cardboard, and selling avocados unripened could further enable the farming enterprise to achieve Net Zero objectives. These measures could reduce baseline emissions from 382.97 kg CO2e/tonne to a theoretical -68.54 kg CO2e/tonne, representing a 117.9% decrease. Although this study does not quantify climate change impacts, qualitative analyses suggest that climate change will have a net negative effect on the avocado industry in South Africa. These regions, typically located in micro-climates, are projected to become wetter and warmer, adversely affecting crop phenology, pest control, road conditions, management complexity, farmer livelihoods, and food security. The study recommends large-scale implementation of the optimisation strategies identified to achieve Net Zero objectives and the development of proactive climate change mitigation strategies to enhance the resilience of avocado supply chains to future stressors. These insights are crucial for policymakers, industry stakeholders, and consumers aiming to promote sustainability in the avocado market.

13.
Ying Yong Sheng Tai Xue Bao ; 35(5): 1379-1387, 2024 May.
Artigo em Chinês | MEDLINE | ID: mdl-38886437

RESUMO

The energy oriented mine ecological restoration mode of photovoltaic+ecological restoration provides a breakthrough for alleviating the dilemma of photovoltaic land development and solving the urgent need for restoration of abandoned mining land. Taking a mining area in central Liaoning Province as an example, we established three photovoltaic+mining ecological restoration modes, including forest-photovoltaic complementary, agriculture-photovoltaic, and grass photovoltaic complementation. Combined with the life cycle assessment method, we calculated and assessed the potential of photovoltaic+mining ecological restoration in carbon reduction and sink enhancement. The average annual carbon reduction and sink increase was 514.93 t CO2·hm-2 under the photovoltaic+mining ecological restoration mode, while the average annual carbon reduction per megawatt photovoltaic power station was 1242.94 t CO2. The adoption of photovoltaic+ecological restoration mode in this mining area could make carbon reduction and sink enhancement 6.30-7.79 Mt CO2 during 25 years. The carbon reduction and sink increment mainly stemmed from the photovoltaic clean power generation induced carbon reduction, accounting for 96.4%-99.4%, while the contribution of ecosystem carbon sink increment was small, accounting for only 0.6%-3.7% of the total. Among different photovoltaic+ecological restoration modes, the carbon reduction and sink increment was the largest in forest-photovoltaic complementary (7.11 Mt CO2), followed by agriculture-photovoltaic (7.04 Mt CO2), and the least in grass photovoltaic complementation (6.98 Mt CO2). Constructing the development mode of "photovoltaic+mining ecological restoration" could effectively leverage the dual benefits of reducing emissions from photovoltaic power generation and increase sinks from mining ecological restoration, which would be helpful for achieving the goal of carbon neutrality in China.


Assuntos
Sequestro de Carbono , Ecossistema , Mineração , China , Recuperação e Remediação Ambiental/métodos , Modelos Teóricos , Carbono/química , Carbono/análise , Conservação dos Recursos Naturais/métodos , Dióxido de Carbono/análise , Energia Solar
14.
Artigo em Inglês | MEDLINE | ID: mdl-38898347

RESUMO

Pharmaceuticals are among the most challenging products to assess by life cycle assessment (LCA). The main drawback highlighted by LCA practitioners is the lack of inventory data, both regarding the synthesis of active pharmaceutical ingredient (API) precursors (upstream) and the details concerning the downstream phases (use and end of life). A short critical review of pharma-LCAs found in the literature is here proposed, with discussion of several tools and models used to predict the environmental impacts derived from the life cycle of pharmaceuticals, emphasizing current strengths and weaknesses, and exploring the possibilities for improvements. The case of antibiotics is selected as a representative class of pharmaceuticals, due to their massive use worldwide and the growing related issue of antimicrobial resistance enrichment, which is generally not included in most of LCAs. Also, we comment on drafting product category rules (PCRs) in the relevant field to develop standard methodologies and enhance the comparability of the studies, ultimately advocating collaboration with companies and improving inventory data quality and availability for the whole value chain of products.

15.
Environ Sci Pollut Res Int ; 31(28): 41208-41220, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38849616

RESUMO

Reasonable treatment of large amounts of sludge excavated from landfills has gained increasing attention due to the diminishing availability of landfill space in China. In this study, five landfill sludge (LS) treatment technologies using life cycle assessment (LCA) and life cycle cost (LCC) were investigated, i.e., co-incineration in coal-fired power plants (CFPP) and waste incineration power plant (WIPP), co-processing in cement kiln, bricks production, and sintering ceramsite. The LCA results demonstrate that sintering ceramsite outperforms other technologies and LCC results indicate sintering ceramsite also provides the highest economic benefit ($869.94). To further enhance environmental and economic performances of the LS treatment, the substitution of coal with natural gas and biomass can reduce Energy Conservation and Emission Reduction (ECER) index by 74% and 98%, respectively. This substitution can increase economic returns by 24% and 26%, respectively. Furthermore, national-level economic benefit and carbon emission reduction potential of different LS treatment technology alternative scenarios were assessed. Results display that a combination of 50% CFPP, 25% bricks, and 25% ceramsite (biomass) offers the highest economic gain, which is 3.02 times that of 50% CFPP and 50% cement (original case). Conversely, the replacement of 25% brick with 25% cement in the above combination result in the lowest carbon reduction, which is 9.35 times that of the original case.


Assuntos
Esgotos , Instalações de Eliminação de Resíduos , China , Incineração , Carvão Mineral
16.
Water Res ; 259: 121889, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38852389

RESUMO

Photocatalytic technology emerges as a promising solution for the sustainable treatment of contaminated wastewater. However, the practical implementation of designed photocatalysts often faces challenges due to the intricate 'high carbon footprint' process and limited outdoor laboratory investigations. Herein, a simple yet versatile impregnation approach is proposed to anchor highly dispersed FeCl3 on a g-C3N4 substrate (Fe-C3N4) with minimal energy consumption and post-processing. Fe-C3N4 enhances photocatalytic reactivity for antibiotic degradation via a synergistic photo-Fenton-like oxidation technique, efficiently removing antibiotic pollutants from actual livestock wastewater. The Fe-C3N4 catalyst exhibited consistent degradation performance over five cycles in laboratory conditions, maintaining a degradation efficiency exceeding 90 % for tetracycline hydrochloride (TCHCl). Furthermore, we engineered a straightforward Fe-C3N4Na2SiO3 reactor for treating livestock wastewater, achieving an 81.8 % removal of TCHCl in outdoor field tests conducted in the winter and summer in China. The Fe-C3N4 catalyst demonstrated high feasibility in treating antibiotic-contaminated livestock wastewater under year-round climatic conditions, leveraging synergistic effects. The stabilization of Fe-C3N4 for the degradation of antibiotic-containing wastewater under sunlight represents a significant advancement in the practical application of photocatalysts, marking a crucial milestone from experimental conception to implementation. Acute toxicity estimation suggested that intermediates/products generated exhibited lower toxicity compared to TCHCl, indicating their practical applicability. Density functional theory (DFT) analysis successfully predicted significant electron transfer between Fe-C3N4 and TCHCl, indicating efficient interfacial interactions on the TCHCl surface. To ensure the environmental sustainability of Fe-C3N4, a life cycle assessment (LCA) was conducted to compared this photocatalyst with other commonly used emerging photocatalysts. The results demonstrated that Fe-C3N4 exhibits a two orders of magnitude lower CO2 equivalent emission compared to the ZnO photocatalyst, indicating a cost-effective and efficient synergistic photo-Fenton-like catalytic approach. This low-cost photocatalyst, moving from the laboratory to real-world wastewater applications, provides a powerful and more sustainable solution for the efficient treatment of wastewater containing antibiotics from livestock farming.


Assuntos
Gado , Oxirredução , Águas Residuárias , Poluentes Químicos da Água , Águas Residuárias/química , Animais , Poluentes Químicos da Água/química , Eliminação de Resíduos Líquidos/métodos , Compostos Férricos/química , Catálise , Ferro/química , Antibacterianos/química
17.
Water Res ; 260: 121954, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38909421

RESUMO

Ferrous (Fe(II))-based oxygen activation for pollutant abatements in soil and groundwater has attracted great attention, while the low utilization and insufficient longevity of electron donors are the primary challenges to hinder its practical applications. Herein, we propose a nanoconfined Fe(II) releasing strategy that enables stable long-term electron donation for oxygen activation and efficient arsenic (As) immobilization under oxic conditions, by encapsulating zero-valent iron in biomass-derived carbon shell (ZVI@porous carbon composites; ZVI@PC). This strategy effectively enhances the generation of reactive oxygen species, enabling efficient oxidation and subsequent immobilization of As(III) in soils. Importantly, this Fe(II) releaser exhibits strong anti-interference capability against complex soil matrices, and the accompanying generation of Fe(III) enables As immobilization in soils, effectively lowering soil As bioavailability. Soil fixed-bed column experiments demonstrate a 79.5 % reduction of the total As in effluent with a simulated rainfall input for 10 years, indicating the excellent long-term stability for As immobilization in soil. Life cycle assessment results show that this Fe(II) releaser can substantially mitigate the negative environmental impacts. This work offers new insights into developing green and sustainable technologies for environmental remediation.

18.
Nanomaterials (Basel) ; 14(11)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38869535

RESUMO

The ceramic tile industry, with significant energy and material demands in its manufacturing processes, has employed technological innovations in energy efficiency, advanced equipment and tile thickness reduction to address these challenges. This study aimed to assess the impact of Ag2O, CuFe2O4, Fe3O4, and SiO2 nanoparticles (0%, 1%, and 5% by weight) on the mechanical strength, water absorption, and apparent thermal conductivity of ceramic tiles, as well as their capacity to reduce energy and raw material consumption. This reduction translates into a decrease in environmental impacts, which have been evaluated through life cycle assessment (LCA) methodology applied to the manufacturing processes. Nanoparticles (Ag2O, CuFe2O4, Fe3O4, and SiO2) were initially screened on TF clay (0%, 1%, 5% w/w), and the most effective were applied to CR1 and CR2 clays (0%, 1%, 5% w/w). Findings indicated a 32% increase in temperature gradient and a 16% improvement in flexural strength with the addition of Fe3O4 nanoparticle at 1% (w/w) in TF clay. Furthermore, there was a potential 48% reduction in energy consumption, and up to 16% decrease in tile weight or thickness without affecting the flexural strength property of the test tiles. LCA results demonstrated that the addition of Fe3O4 nanoparticle has potential reductions of up to 20% in environmental impacts. This study suggests that nanoparticle addition offers a viable alternative for reducing energy and material consumption in the ceramic tile industry. Future research should focus on assessing the economic impact of transitioning to a sustainable business model in the ceramic tile industry with nanoparticles addition.

19.
J Environ Manage ; 362: 121251, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38823295

RESUMO

The production of biogas from microalgae has gained attention due to their rapid growth, CO2 sequestration, and minimal land use. This study uses life cycle assessment to assess the environmental impacts of biogas production from wastewater-grown microalgae through anaerobic digestion within an optimized microalgae-based system. Using SimaPro® 9 software, 3 scenarios were modeled considering the ReCiPe v1.13 midpoint and endpoint methods for environmental impact assessment in different categories. In the baseline scenario (S1), a hypothetical system for biogas production was considered, consisting of a high rate algal pond (HRAP), a settling, an anaerobic digester, and a biogas upgrading unit. The second scenario (S2) included strategies to enhance biogas yield, namely co-digestion and thermal pre-treatment. The third scenario (S3), besides considering the strategies of S2, proposed the biogas upgrading in the HRAP and the digestate recovery as a biofertilizer. After normalization, human carcinogenic toxicity was the most positively affected category due to water use in the cultivation step, accounted as avoided product. However, this category was also the most negatively affected by the impacts of the digester heating energy. Anaerobic digestion was the most impactful step, constituting on average 60.37% of total impacts. Scenario S3 performed better environmentally, primarily due to the integration of biogas upgrading within the cultivation reactor and digestate use as a biofertilizer. Sensitivity analysis highlighted methane yield's importance, showing potential for an 11.28% reduction in ionizing radiation impacts with a 10% increase. Comparing S3 biogas with natural gas, the resource scarcity impact was reduced sixfold, but the human health impact was 23 times higher in S3.


Assuntos
Biocombustíveis , Microalgas , Águas Residuárias , Microalgas/metabolismo , Microalgas/crescimento & desenvolvimento , Águas Residuárias/química , Anaerobiose , Meio Ambiente
20.
J Environ Manage ; 362: 121339, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38824897

RESUMO

To promote optimal phosphorus (P) recovery from municipal wastewater and sewage sludge with viable legal instruments, it is imperative to understand the regional and national consequences of different legal requirements for recycling. In this study we develop a scenario-based analysis to assess the environmental and economic impact of different national P recovery strategies in the context of a detailed representation of the existing Austrian wastewater infrastructure. This assessment combines material flow analysis, life cycle assessment and life cycle costing and includes the indicators P recycling rate, P utilization degree, heavy metal removal rate, share of heavy metals' content in wastewater redirected to agricultural soils, global warming potential, cumulated energy demand, terrestrial acidification potential, volume of freight transport and annual costs. The following main conclusions can be drawn. P recovery from ash shows the highest potential regarding the utilization of P from wastewater. A high P utilization from wastewater should rely on recovery technologies that decontaminate products, otherwise pollutant loads to agricultural soils might increase. P recovery to the extent of 60-85 % of P in WWTPs influent can be achieved by savings/costs of -0.8 to +4.7 EUR inhabitant-1 yr-1 in addition to current cost of the wastewater treatment/sludge disposal system. Key factors to be considered for costs are the choice of recovery process, revenues from products, and the use of existing incineration infrastructure. P recovery can lead to the reduction of greenhouse gas emissions in Austria if nitrous oxide emissions from sludge incineration are limited and efficient heat utilization strategies are implemented. There is a trade-off in terms of environmental and economic costs in choosing a more centralized or decentralized mono-incineration strategy.


Assuntos
Fósforo , Reciclagem , Esgotos , Áustria , Águas Residuárias/química , Eliminação de Resíduos Líquidos/métodos , Metais Pesados
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