Cleaner Environmental Systems最新文献

The emergence of a post-growth era is expected that implies rethinking the production and consumption patterns with novel design models this forces higher educational institutions to reconsider their traditional ways of teaching sustainability in their curricula. Companies also need to overcome strategies that compartmentalize environment, society and economy in their industrial strategy in order to evolve in their support for the transition. The aim of this paper is to present a design process anchored in the Strong Sustainability paradigm to overcome the gap of how Strong Sustainability could be operationalised. Design Research Methodology (DRM) has been chosen as the supporting framework for the development of this project. The Design for Strong Sustainability (DfSoSy) methodology proposed, is built on three aspects of Strong Sustainability (Milieu, Regeneration, Safe and just operating space) successively applied in a sequenced iterative design process. The latter enable the integration of thought patterns associated with integrative, systemic and fractal or multi-scale thinking respectively. Moreover, the principle of sub-optimality is highlighted as a decision principle in SoSy. Results obtain has been validated as well on the pedagogical objectives as in the usefulness of the DfSoSy. The practical contribution of this study is the DfSoSy toolkit©.

According to FAO projections, meat and fish production will have to increase by 70% by 2050 to meet the needs of the growing global population and its protein requirements. The poultry sector has been one of the most responsive industries to the growing demand for protein, with a significant increase in egg and chicken meat production. Although eggs are important foods in the human diet, environmental impacts and ethical aspects could also affect dietary choices. This study aimed to assess the environmental impacts of egg production, by using Life Cycle Assessment (LCA). More specifically, the study compared two different farming systems of conventional and organic egg production, with reference to two case studies in northern Italy. The results obtainedgenerally showed the conventional system to be more efficient compared to the organic system. For example, as regards the impact category of Fine particulate matter formation, the conventional system had a 28.6% lower impact than the organic system. Another major difference was in the Land use category, where the conventional system had an impact of 48.5% less than the organic system. The Organic Scenario showed some critical aspects, e.g. the need for a large agricultural area, low feed conversion rates and low crop yields. The two production scenarios showed that in terms of environmental impact, the main difference between organic and conventional egg production resides in feed production. I It is, therefore, essential to work on a low input formula, to substitutethe diet components with the greatest impact and adopt strategies to obtain an increase in yields and/or a reduction in resource consumption during the cultivation phase. The complete substitution of soybean with other local crops could reduce several impacts, including the one linked to transport. The further reduction of maize could also limit the expected impact.

Student restaurants at Chalmers University have adopted take-away lunch boxes as a convenient dining option for students with disposable single-use containers being the norm. However, there is a growing interest in more sustainable, reusable alternatives. This study conducted a comparative Life Cycle Assessment (LCA) to assess the potential environmental and economic impacts of using reusable lunch boxes in comparison to disposable ones, considering 18 environmental impact categories. The functional unit chosen for evaluation was the provision of takeaway lunches to Chalmers students over the course of a year. The findings revealed that reusable boxes with 20 uses outperformed their disposable counterparts in many environmental impacts, reducing the climate change impact by 59%. However, water and energy consumption were higher for the reusable option by 99% and 62% respectively, primarily due to the cleaning process. From an economic perspective, reusable boxes proved to be 3.3% more costly than disposable ones. In conclusion, this study highlights the benefits of reusable solutions, showing reductions in various environmental footprints but presenting slightly higher economic footprints over 20 uses. However, as the number of uses increases, the advantages also increase, leading to recommendations for better management of the lunch boxes to maximize their reusable potential.

Phosphorus is a finite resource that is in high demand due to its essential role as a fertiliser. We undertook a substance flow analysis of phosphorus for India's agri-food system to identify where the biggest losses of phosphorus occur and which flows could be targeted to move phosphorus from a linear use and waste approach to a circular approach encompassing recovery and re-use. A novel aspect of the analysis was the inclusion of sanitation systems in India. National phosphorus flows were calculated annually for the five years 2015–2019, and the mean was then used to provide a representative annual flow. The analysis showed that India is dependent on imports for 95% of applied mineral phosphorus fertiliser and has a low phosphorus-use efficiency of 32%. The largest recoverable flow is human excreta (urine and faeces), equivalent to 21% of the current phosphorus applied in mineral fertiliser in India. Phosphorus recovery from septic tanks, the most prevalent sanitation system in India, could alone replace 8% of phosphorus applied in mineral fertiliser in India. Alongside the ongoing development of sanitation systems in India this provides an opportunity to ensure that nutrient recovery is included in sanitation developments.

We evaluated CO₂ equivalent (CO₂eq) greenhouse gas (GHG) emissions and minimum selling price of levulinic acid (LA) produced in two biomass-waste-based processes: the AlCl₃/choline chloride (ChCl) process, and the formic acid (FA) process, with catalysts recycling. Six scenarios were synthesized to compare the performances of the two processes in Japan and Canada. In the AlCl₃/ChCl process, the total GHG emission was 11.35–11.56 kg-CO₂eq/kg-LA and those from the energy input to the pretreatment and ChCl production were 5.22 and 3.90 kg-CO₂eq/kg-LA, respectively. In the FA process, the total GHG emission was 9.46–9.68 and 22.29–22.51 kg-CO₂eq/kg-LA for 60 wt% and 80 wt% FA, respectively. The operational emissions for makeup FA input were 7.65 and 20.80 kg-CO₂eq/kg-LA (60 wt% and 80 wt%, respectively), which accounted for more than 80% in all scenarios. The optimization of the product purge volume, FA concentration in the pretreatment, and FA production using biomass and/or renewable energy are critical parameters to reduce overall environmental impacts of the processes. The liquid content of the solid residue (moisture, water soluble organic matters, and catalyst) had insignificant influences on the GHG emission and minimum selling price. In the FA process, combustion of solid residue can compensate the GHG emissions from the reaction and separation units.

In the face of escalating emission reduction demands and heightened public awareness, the imperative for transparent assessments is fundamental to responsible and sustainable development. The use of life cycle assessment (LCA) is instrumental in identifying environmental hotspots in intricate systems and guiding the design and selection of environmentally conscious production methods. However, LCA's comprehensive approach demands substantial data, fundamentally material and energy flows for individual materials or processes, consolidated within a life cycle inventory (LCI). The amount of time, resources, and expertise required to compile an accurate LCI dataset are among the greatest concerns for LCA practitioners. During the early design phase for industrial-scale production, process simulation is a useful tool for estimating LCI data; however, first-principle models can sometimes be unfeasible. This has prompted researchers and engineers to advocate for simplified or surrogate versions of these intricate models in some particular cases. In contrast to first-principle models, machine learning (ML) models efficiently manage extensive datasets and complex systems without rigorous model equations. This work assesses the current state of ML-LCA integration through literature and bibliometric analysis, categorizing works into three clusters and identifying publication trends. Furthermore, this analysis yielded three frameworks aimed at facilitating the integration of ML techniques into LCA workflows, enhancing precision and efficiency in environmental impact assessment. The first framework revealed the interest in abstracting a complete process into a surrogate ML model for fast LCI predictions. Conversely, the second one focused on substituting a complex part of the process for an ML surrogate model based on data from experiments or literature. Finally, in the third framework, LCA performance was directly correlated with a system characteristic, enabling direct and fast predictions of LCIs or LCA performance indicators, and optimization in not yet designed systems.

The pros and cons of the organic and conventional systems of pineapple cultivation have not been studied extensively. Non-consideration of full crop cycle and non-incorporation of environmental externalities are among the other gaps in research. The present study therefore compared Conventional Cultivation System (CCS) and Organic Cultivation System (OCS) of pineapple grown in Sri Lanka using Life Cycle Assessment (LCA) under five impact categories considering system boundary from gate-to-gate and the full crop cycle. Economic analysis was conducted to determine the best system considering positive and negative externalities. Results showed 87% reduction of Global Warming Potential and 89% reduction of Eutrophication Potential under OCS. Higher toxicity potentials were reported under CCS while OCS resulted in zero toxicity. The net benefit for the farmer under OCS was higher. When the externalities were incorporated, the OCS showed a net gain of USD 8208 per ha while the CCS was no longer beneficial (USD -21,162 per ha). The study proposes economic instruments to incentivise farmers and emphasises the need to minimise adverse impacts of pesticides in sensitive locations. The study also highlights the potential of LCA studies when coupled with monetary values in guiding policy to incentivise farmers towards sustainable pineapple production.

The manufacturing industry increasingly needs to shift toward energy-efficient production patterns to address both environmental pollution reduction and higher energy prices. Despite efforts to enhance energy efficiency and to close the energy efficiency gap in small- and medium-sized enterprises (SMEs) limited awareness, lack of know-how, and restricted financial and human resources still hinder large-scale adoption. This is partly because current research on energy flow analysis (EFA) often lacks structured and detailed methodologies and neglects a suitable evaluation of potential greenhouse gas (GHG) emission reductions. In response, we derived a framework from existing literature and applied action research to tailor it to identify energy flows and cost-effective reduction potentials for GHG emissions in SMEs. The framework aims to improve awareness, transparency, and decision-making regarding energy consumption and environmental protection within SMEs by combining GHG accounting with comprehensive EFA to enhance energy efficiency. Furthermore, the framework outlines specific activities to guide SMEs through the implementation process. Two case studies were conducted in partnership with companies operating in the automotive and environmental sectors to develop and validate the framework. Although the case studies focused on non-energy-intensive industries, they revealed untapped potential for reducing energy consumption. Both case studies showed reductions in energy use through the identified measures, achieving reductions of 900,000 kWh and 1,300,000 kWh, respectively. At 2021 energy price levels, these reductions led to a significant drop in energy costs: a 16% drop in case one and 22% in case two. Additionally, insights from the case studies have led to further refinements of the framework, emphasizing the necessity of tailored solutions and resource considerations for SMEs. These findings helped to identify opportunities for future research directions toward optimizing energy management practices in SMEs.

Plastic waste mismanagement is a pertinent environmental concern among developing countries. The Philippines has a significant plastic waste concern as the country is among the top emitters of plastic wastes to the ocean. To manage plastic wastes, the government enacted policies. resulting to paper carrying bags becoming a prominent alternative. Switching from one carrying bag to another, however, requires clear assessment on the environmental implications as environmental trade-offs can occur. To provide the needed clarity, this study assessed the environmental implications of plastic and paper carrying bags through a life cycle assessment (LCA) approach. This study developed a model with the novelty of a) supply chain integration, b) augmented Environmental Design of Industrial Products (EDIP) impact assessment, and c) inventory categorization. From the augmented EDIP assessment, paper carrying bags had a single score impact of 0.73 whereas plastic carrying bags had a single score of 0.63. In terms of geographic emissions, this work revealed that paper carrying bags emit 50.28% of its emissions outside the country whereas plastic carrying bag emit 34.72%. Policy recommendations derived from the findings are provided in this paper. Recommendations include carbon capture and storage, green procurement, circular management, and waste management system improvement. Policy makers may infer from the recommendations in managing environmental issues from the use of carrying bags.

Dog food accounts for 90% of the average dog's impact on climate change. Vegan dog food is one possible alternative. There are few studies evaluating its environmental impacts. The goals of this paper are to i) determine the environmental impacts and hotspots of wet vegan dog food, ii) compare results with average meat-based alternative and estimate global climate change potential of switching from meat-based to vegan dog food diet. A life cycle assessment was performed for a can of vegan dog food for the categories climate change, freshwater eutrophication, terrestrial acidification, smog, and land use. Each can had a carbon footprint of 0.4 kg CO₂-eq., adding up to 443 kg CO₂-eq over a dog's 15-year lifespan. A comparison with meat-based dog food showed reduction potentials in acidification by 50%, climate change by 37%, and smog by 18%, but higher impacts in land use by 97%, and eutrophication by almost 300% applying the assumptions by Pet Food Industry Federation. The results differ from other studies showing reductions in land use and eutrophication. Switching to a vegan diet can reduce GWP emissions by 340 kg CO₂eq per year, while this could increase up to 6000 if high quality meat is fed.