Cleaner Environmental Systems最新文献

This study offers essential metrics for informed decision-making in the context of transforming traditional industrial estates into circular economies. The study conducts a systematic analysis of an existing industrial zone, demonstrating its potential transition towards a circular approach while assessing its economic viability and avenues for enhancement. The paper unfolds as follows: It initially presents a comprehensive methodology for quantifying the economic value added through recycling within the industrial zone. Subsequently, it introduces a method to compute the economic value associated with the remaining waste generated within the industrial zone. The paper then proposes a novel approach for determining the circularity factor of an industrial zone, effectively quantifying the degree of circularity achieved within the zone. Finally, it integrates circular economic principles and outlines a framework to assess the circularity value across the entire manufacturing process, reducing waste and reintegrating it into the material supply chain. The study provides a robust methodology for calculating circular value addition within an industrial zone. Furthermore, these metrics are applied to Biyagama Export Processing Zone (BEPZ), in Sri Lanka as part of the study's empirical analysis. The circularity factor of the zone was 0.4, and it clearly identifies that the total economic value addition of the zone can be maximized through the practice of a circular economy.

Life cycle assessment (LCA) is a powerful tool to evaluate the environmental impacts of any domestic or industrial activity consuming goods and services. There has been an increasing interest in recycling polymers and polymer composites for circular economy and sustainability; however, the widespread use of polymers should be avoided upfront, especially for research and development. LCA is performed to evaluate the environmental impact of two characterization approaches (numerical modeling and experimentation) used for additively manufactured polymers and composites. The current study was conducted using GaBi software, per the International Organization for Standardization (ISO) 14040 and 14044 guidelines. Five different environmental impacts, namely global warming potential (GWP), acidification potential (AP), eutrophication potential (EP), ozone layer depletion (ODP), and fossil fuel depletion (FFD), were evaluated and compared for numerical modeling and experimental characterization approaches. Electrical energy used during the filament fabrication, 3DP process, and mechanical testing was identified as a hotspot in the environmental impacts (GWP, AP, EP, and FFD) for experimental design. However, the materials consumed during the experimental characterization contributed considerably to ODP. Results concluded that using the numerical modeling approach could significantly reduce the environmental impact caused due to extensive resource utilization in experiments. The numerical modeling approach can help promote sustainability as these tools can adequately predict the response of 3D-printed structures; therefore, they should be explored and improved further.

In the railways sector environmental concerns are growing, and many state-owned holding companies are investigating which is the best superstructure solution from the environmental point of view. In this regards, in the last years some companies have proposed ballastless systems, to reduce the replacement and maintenance activities and increase the reliability of the solution. Nevertheless, some environmental discussion emerged, even bearing in mind of different reference service lives.

This study aims at comparing from an environmental point of view a ballasted and ballastless solutions using Life Cycle Assessment, by considering a declared unit of 1 km of railways infrastructure located in Italy. Results show the ballastless system has, on the contrary of previous studies, the lower environmental impact, due to its extended shelf life (90years) and low maintenance activities if compared with a ballasted one. Considering the same timeframe, the ballastless system has about halved impact on climate change (3.33E+06 kg CO₂eq) compared to the ballasted one (1.75E+06 kg CO₂eq). A sensitivity analysis has been carried out to consider possible variations in reference service life, transports and interval of rails substitution.

The citrus sector represents one of the main agri-food supply chains in Italy, which today is the second largest producer of citrus fruits in Europe. Consequently, its impact from an environmental, economic and social point of view can be considerable and it is therefore necessary to assess the sustainability performance of this supply chain. Life Cycle Assessment (LCA) studies are nowadays an important tool for the improvement of production standards and for better decision support by entrepreneurs and public decision makers. This work aims to review in a systematic way the scientific literature on LCA applied to the citrus fruit sector and was conducted following the STARR-LCA checklist approach. The survey was conducted through the main bibliographic databases: Scopus, Web Of Science and Google Scholar, adopting specific search criteria depending on the tool used; the search led to a final selection of 42 articles. The analysis of the papers was conducted using various parameters such as: topic, methodology applied, system boundaries, functional units, allocation criteria, inventory analysis and impact assessment. The analysis of the results shows an overview of the state of the art of LCA approach applied to the citrus sector and can provide useful data and information for practitioners as well as a basis for further methodological developments.

Pig slurry is an agricultural residue with potential for utilisation as organic fertiliser and biomethane feedstock. That potential value is typically diminished via greenhouse and ammonia gaseous losses during temporary storage, an issue further exacerbated by the global warming, pollutant and malodorous nature of those compounds. Existing methods of reducing emissions from pig slurry may require significant capital outlay and/or may prove difficult to retrofit. A promising reactive oxygen-based additive (GasAbate®) was thus scaled-up to 1 m³ tanks filled with 750 L weaner slurry. Several experiments were carried out in three distinct phases, namely i. ambient temperature scale-up; ii. heated 1 m³ trials to determine optimal application method; iii. heated 1 m³ trials to compare results in static and dynamic chamber scenarios, with each iteration aiming to garner understanding of treatment efficacy under various conditions. The results demonstrate the scalability of this additive, its efficacy in reducing total volume of gaseous emissions (63–90% reduction), ammonia emissions (22–58% reduction) and malodorous compound evolution (22–83% reduction for a range of compounds) during temporary storage and the resulting retention of energy and nutrient value in the slurry, with 34–57% higher biomethane potential. The use of this additive could be well suited to farms that require short-term slurry storage (ca. 30 days) before feeding the slurry to a biogas system.

More sustainable pastoral livestock production systems are required to face the challenge of reconciling agricultural production and environmental impact. Although the need for more holistic approaches, such as systems thinking and design theory, is acknowledged, systemic research applying those theories to create healthier systems remains underexplored. A multiple steps holistic approach involving modelling, geographic information systems, and decision-making analysis was used to design, assess, and contrast alternative scenarios that represent distinct grazing management to the current grazing management of a high-country station in New Zealand used as a case study to enhance grassland health. Three alternative scenarios were created, and five main parameters used to assess grassland health were obtained from the evaluation of the designed scenarios. From all the parameters, soil erosion control and increased production were ranked as the most and least important, respectively, to be considered in the design process. A multi-criteria evaluation defined that the best-compromise scenario to enhance grassland health is the scenario with lower soil erosion, as a result of applying adaptive and flexible management at the paddock level, the lower total emission of greenhouse gases (only sheep herd grazing), and greater profitability (due to production costs reduction, as cattle were removed from the station), compared to the ‘status quo’. Our design methodology produced a variety of alternatives that enhanced the health of grasslands in different parameters while still maintaining or increasing profitability. The use of multi-criteria evaluation facilitated the decision of the most contextualised and best-compromise scenario for New Zealand high country grasslands.

Health care accounts for 9–10% of greenhouse gas (GHG) emissions in the United States. Strategies for monitoring these emissions at the hospital level are needed to decarbonize the sector. However, data collection to estimate emissions is challenging. We explored the potential of gradient boosting machines (GBM) to impute missing data on resource consumption in the 2020 survey of a consortium of 283 hospitals participating in Practice Greenhealth. GBM imputed missing values for selected variables in order to predict electricity use (R² = 0.82) and beef consumption (R² = 0.82) and anesthetic gas desflurane use (R² = 0.51), using administrative and financial data readily available for most hospitals. After imputing missing consumption data, estimated GHG emissions associated with these three examples totaled over 3 million metric tons of CO₂ equivalent emissions (MTCO₂e). Specifically, electricity consumption had the largest total carbon footprint (2.4 MTCO₂e), followed by beef (0.6 million MTCO₂e) and desflurane consumption (0.03 million MTCO₂e) across the 283 hospitals. The approach should be applicable to other sources of hospital GHGs in order to estimate total emissions of individual hospitals and to refine survey questions to help develop better intervention strategies.

Objective

This study combines Integer Linear Programming (ILP) and carbon footprint analysis based on the Life Cycle Assessment (LCA) method to reduce the carbon footprint of surgical instrument trays and their use.

Materials and methods

A case study was carried out quantifying the instrument usage during the radical hysterectomy procedure. Using LCA we modelled the carbon footprint of the instrument trays, cradle to grave. The resulting carbon footprint data were used as input for an ILP model. The ILP model aims for an environmentally optimized composition of surgical instrument trays, without influencing patient safety, and optimizes composition based on different utilization rates.

Results

Instrument usage for the radical hysterectomy procedure was 54%. The LCA showed that with 99.5% of the total carbon footprint, the use phase in which the surgical trays are cleaned and sterilized is the biggest contributor. The ILP showed that for the radical hysterectomy procedure, an annual reduction in emission of 230 kgCO₂-eq (46%) can be achieved by optimizing the trays.

Discussion

The results of this study show that the carbon footprint of surgical instrument trays is mainly impacted by the surgical tray size and number of used trays. Implementing the proposed method and environmentally optimizing surgical trays requires a multidisciplinary team, including surgeons, OR scrub nurses and those who have knowledge of LCA and ILP.

Conclusion

A combined method of ILP and LCA is suitable to provide insights on how to optimize surgical instrument trays with the objective to reduce the carbon footprint of these trays.

Unsustainable food supply chains are sources of relevant environmental impacts and strongly contribute to the depletion of non-renewable resources. Ecolabelling is one of the measures for increasing market awareness of the sustainability of a product and encourage the implementation of low-input practices along the food production system. Made Green in Italy (MGI) scheme is an initiative based on the PEF method and aimed to reward Made in Italy products with high environmental profile. A screening study was conducted on four Sardinian dairy plants to develop an experimental MGI application on the hard sheep milk cheese supply chain, using Pecorino Romano PDO as reference product. Sheep milk phase resulted the main contributor for all relevant impact categories (over 94%). Benchmark score (1.33E-05 Pt) was calculated adding the normalized and weighted values of the 3 main relevant impact categories (Climate Change, Land Use and Water Scarcity). Three performance classes were defined considering the best and the worst values of life cycle processes: upper threshold was equal to 1.62E-05 Pt and lower threshold was equal to 1.17E-05 Pt. The relevant sheep milk impact highlighted the crucial role of sheep farming systems for improving the environmental footprint of the Pecorino Romano PDO.