Cleaner Environmental Systems最新文献

Wastewater reuse could provide a substantial relief from water scarcity, particularly for agricultural and industrial purposes. To meet future legislation and environmental standards in this regard, organic micropollutants must be efficiently eliminated in the treated effluent. Innovative water treatment technologies can contribute to achieve this goal, but their environmental consequences must be controlled. The objective of this study is to assess the environmental hotspots of an enzyme-based wastewater treatment system for the removal of sulfamethoxazole (SMX) as a model pollutant. For this purpose, the Life Cycle Assessment and Product Environmental Footprint methodologies have been applied to a conceptual process design based on laboratory-scale data. In addition, we addressed the relevant process parameters (i.e., the stability and reuse of the enzyme and the impacts associated with its immobilization), the comparison with consolidated technologies (membrane and ozonation systems) and the geographical situation (such as the electricity mix and the water stress level). The main hotspot of the analyzed treatment process is the production of the unspecific peroxygenase used within the magnetic biocatalyst, contributing more than 36 % to all impact categories considered. Focusing on the magnetic biocatalyst synthesis, the enzyme production phase and the functionalization of the immobilization support are the most problematic (with percentages of up to 75 % in stratospheric ozone depletion and 65 % in terrestrial ecotoxicity, respectively). In relation to resource consumption, water demand has been estimated at 0.02 m³ per cubic meter of treated water, but water deprivation can be much higher depending on the country (∼0.5 m³). Therefore, the use of reclaimed water can offset the indirect effects of its treatment. This study serves as a roadmap for future research to achieve reduced emissions by reduction of energy requirements, the use of renewable energy but also by increasing the enzyme stability. Furthermore, the background environmental impacts of the production of the biocatalyst must be reduced to improve the competitiveness against implemented alternatives based on physical (membranes) and chemical (ozonation) processes.

The environmental sustainability of business activities and operations is an increasingly relevant issue. The Board of Directors, by the means of its monitoring role, affects a firm’s achievement of both economic and non-financial objectives. The nomination committee defines the criteria for the selection of Board members and determines the most suitable profiles of the candidates. This paper studies the effect of the level of independence of the nomination committee on a company’s environmental performance. The study analyzes a sample of European non-financial listed firms for the period 2014–2022. Findings indicate that the level of independence of the nomination committee positively and significantly affects corporate environmental performance and the effect is mediated by the level of independence of the Board of Directors.

Corporate social responsibility (CSR) and its impact on corporate value has been widely debated. Two opposing views have emerged: stakeholder value maximization and shareholder expense. In this study, we explore these perspectives within the realm of mergers and acquisitions (M&A), one of the most important and far-reaching corporate decisions. Specifically, we examine whether the CSR of the acquiring company impacts M&A performance by analyzing a European sample of 1549 M&A deals announced between 2005 and 2019. Our findings indicate that CSR has a negative effect on stock performance around the M&A announcement, which aligns with the shareholder expense view. We argue that in Europe, where corporate social responsibility (CSR) is already elevated as a result of EU policies and regulations, additional CSR investments may not align with the best interests of shareholders. This serves as an illustration of a Too-Much-Of-A-Good-Thing Effect. However, we also see that CSR has no significant effect on operating performance, which may indicate a financial bias of capital market participants or suggests that investors weigh their own cost-benefit considerations when assessing acquirers' CSR performance.

Modern agriculture is linked to desertification, massive biodiversity loss and environmental degradation of the ecosystems. In contrast, crop rotation represents an agronomic approach included in conservation agriculture with important environmental and agronomic benefits, such as N fixation, pest and weed control, improvement of soil characteristics and reduction of crop fertilizer demand. Wheat is a staple food in Morocco, as are legumes, which are present in a wide variety of Moroccan recipes and represent an important source of energy and nutrients. The present study evaluates the environmental performance of incorporating chickpea and lentils in a crop rotation system in Morocco that aims to decrease the environmental footprint of the traditional wheat-based crop. An attributional Life Cycle Assessment was conducted in three cropping systems that are grown in two-year cycles: R1 (chickpea:wheat), R2 (lentil:wheat) and M (wheat:wheat). Emissions were quantified in terms of life-cycle related environmental impacts and compared between cropping systems based on two functional unit (kg of wheat harvested). Rotation systems stand out as the most environmentally friendly, with the most notable reductions in the categories of stratospheric ozone depletion and water scarcity (34 % and 50 %, respectively). The environmental improvement from crop rotations was most significant when considering the calculation basis of hectare cultivated versus kg of wheat, which is due to the estimated yield trade-offs in both approaches. In terms of biodiversity loss, no significant differences were observed between crop rotations and monoculture, as the impact on this indicator is mainly attributed to land conversion pressures. This study provides guidance for better formulating crop rotation strategies in the Mediterranean and similar arid regions. Future research should also assess the effects of agriculture on ecosystem services to provide a more comprehensive analysis to support decision making.

Global agricultural systems are increasingly moving towards organic farming to satisfy consumers’ increased environmental awareness. Yet, shortage of fertilizers and more frequent water stresses are challenging agricultural systems to minimize their environmental impact without compromising productivity and economic sustainability. This study discusses how greenhouse organic tomato production behaves when multiple eco-sustainable solutions are applied. In particular, organic tomato cultivation was supported by a specific biostimulant treatment that included a microbial solution, based on Rhizobium, which was distributed onto faba bean seeds; once a suitable fava bean biomass had been obtained, the plants were chopped and incorporated into the soil in order to release nitrogen. In the trials considered, microbial solutions reduced organic tomato production costs by 5 %. Considering that fertilization accounted for up to 7 % of total production costs, a large-scale preparation of the microbial solution could trigger significant economic savings. The Life-Cycle Assessment shows that organic tomatoes, with a lower yield, have a lower environmental impact than conventional production only for 7 of the 15 evaluated impact categories. Combined agro-technical growing solutions are economically viable in the presence of yields in organic compared to conventional, and their environmental impact is attractive in both scenarios.

Seasonality and within day variation are important characteristics of electricity supply/demand and for emissions from electricity generation. This paper investigates the social costs of using electricity at different times of the day, allowing for seasonal patterns and differences between weekdays and weekends in Sacramento, California in 2013 and 2019. The social costs of electricity use refer to a combination of the emission costs and the electricity price. Using simulations for the social costs of CO₂, results show that the highest costs of using electricity occur at different hours across seasons on weekdays and weekends. As CO₂ price increases, the social costs of electricity use become more volatile, but it becomes more pronounced that the low costs hours shift to daytime hours for most seasons in both years, except summer and spring 2019. This pattern helps evaluate the social impacts of using electricity and providing policy implications for electricity demand changes.

Voluntary carbon offset markets play an important role in climate change mitigation by deploying technologies in order of lowest abatement cost. The objective of this study is to identify the key drivers of changes in the volume of carbon credits issued in voluntary registry offset markets from 2006 to 2020 using a decomposition analysis framework. The results show that the volume of issued carbon credits related to forestry and land use increased from 2006 to 2015 due to priority increases and scale expansions in REDD+ projects. In addition, the reasons for the priority changes in carbon credits issued varied according to the scale of carbon offset programs in each region. The comparison of scale effect and carbon offset program priority is a useful tool for understanding changes in carbon credits issued according to project technology and region. The very rapid increase in forestry carbon credits issued does however pose important policy implications given it has been accompanied by widespread indications of poor governance and questionable outcomes in terms of CO₂ reduction. In light of the IPCC's reliance on carbon credits the need for thoroughgoing policy reform is underlined.

The study examined the precursors of circular practices among waste management firms in Ghana. Its objectives were to assess the internal financial environment and the external financial environment of the firms as the precursor of its circular economy practices The study used a cross-sectional design and a quantitative research method. Data was collected from the owners/managers of integrated waste management firms in the Environmental Service Providers Association of Ghana database. On that note, 524 firms participated in the survey. The data was collected using a closed-ended questionnaire consisting of a seven-point Likert-like scale. The findings show that the factors influencing the adoption of circular economy techniques by waste management companies in Ghana include the internal environment that is firm-level financial environment, financial readiness, and investment readiness. External factors such as country level financial environment and international level financial environment were not significant precursors. It is advised that companies in the circular economy, such as waste management companies, establish the enabling conditions for moving ahead with sustainable business practices.

Over the past decade, digitalization and digital technologies (DTs) have undergone rapid evolution, transforming how goods and services are produced and consumed in modern societies. Health and well-being sectors have embraced this digital revolution. Besides the economic and social benefits, digitalization can significantly enhance patient diagnostics and prognostics while improving overall service efficiency. To ensure long-term sustainability, it is important to assess and reduce the environmental impacts of digital services. This article examines the life cycle impacts of a digital service implemented in three elderly living schemes (ELSs) located in the United Kingdom (UK). The digital service consists of six electronic devices (EDs) that enable communication between residents, visitors, staff, and offsite monitoring (OM). The equipment is connected using Power over Ethernet (PoE) technology, which includes smart network switch and uninterruptable power supply units. The digital service's global warming potential (GWP) was estimated at 718–741 kg CO₂ eq./resident for two of the ELSs and 1509 kg CO₂ eq./resident for a third ELS, considering a service period of 20 years. The reason for the significant difference is the greater use of air conditioner (A/C) units to cool down server rooms and fewer residents in the third scheme. The consumption of electricity was found to be the main contributor to most of the environmental impacts. However, in certain categories such as mineral resource scarcity, freshwater eutrophication, and freshwater and marine ecotoxicity potentials, printed circuit boards (PCBs) were the main contributors. A sensitivity analysis considering different national electricity mixes demonstrated that the French electricity grid promoted the reduction in 14 impact categories, whereas the German, Italian, Spanish and Japanese grids increased on average impacts on most categories. Another sensitivity analysis demonstrates that reducing A/C unit running time by 28% resulted in an average impact reduction of 5.5%, becoming equivalent to the results obtained for the French electricity grid. Finally, extending the expected lifespan of electronic equipment by 20% yielded the highest average decrease in environmental impacts (8.1%). While digitalization has the potential to enhance patient healthcare and reduce costs, it is crucial to carefully assess its environmental impacts and implement mitigation strategies to ensure sustainable development in the healthcare sector.

Wastewater treatment systems produce environmental impacts in their construction and operation, and nature-based treatment processes offer opportunities to reduce the environmental burdens. Constructed wetlands represent such a solution that can remove micropollutants from municipal effluent. This study evaluates life cycle impacts and environmental risk of constructed wetlands for improved treatment performance. The assessment of laboratory- and pilot-scale installation performance provides insights into sustainability of scaling fundamental research to technology demonstration. The normalised life cycle assessment showed that the laboratory installation generated higher environmental impacts than the pilot, due to the cooling tank and its associated electric power (∼60% of the total burdens for five impact categories). The avoided environmental impacts through the micropollutants' elimination ranged from 50% to 99.9% (for freshwater ecotoxicity and human toxicity, respectively). A sensitivity and uncertainty analysis highlighted how the substrate and electricity demands represented the highest environmental impacts, thus extending lifespan of a full-scale system whilst maintaining treatment performance represents the most notable opportunity to improve the environmental performance. The findings support measures to enhance sustainability through design, procurement and operation stages of development. Constructed wetlands represent a sustainable nature-based form of wastewater treatment, and this study offers lessons to further enhance their environmental performance.