Resources Conservation and Recycling最新文献

Cities are positioning themselves at the center of the Anthropocene, hosting most of the world's population and global socioeconomic activities. The increasing prospect of escalating climate hazards is threatening cities and citizens worldwide, indicating the unprecedented importance of urban climate resilience building. However, the disconnect between resilience scholarship and practical policymaking hinders effective, evidence-based policymaking. By analyzing case-based, peer-reviewed articles worldwide, this study reveals the status of current resilience-building policies and the gaps therein. The results suggest that less than a third of the literature discusses policy implementations, with a notable absence of macro-level policies and crisis management toolkits. The authors underscore the potential integrated pathways to transcending the traditional place- and community-based resilience building practices, emphasizing the importance of integrating scholarly insights into practical policy frameworks for a more resilient urban future.

Sustainable urban development critically depends on effectively managing the interplay between material stock (MS) and economic growth. This study combined convolutional neural network model and nighttime lights data to map building MS of Yangtze River Delta (YRD) urban agglomeration in China from 2000 to 2020 across 1 km × 1 km pixel scale, then uncovered the spatiotemporal dynamics of MS and its correlation with economic development. Our findings indicate that the model performed robustly on the test set (R² > 0.88). YRD's MS surged over tenfold, reaching 20,772 teragram, primarily expanding along northwest-southeast developmental axes. Most YRD cities exhibited synchronized growth in material stock and GDP, suggesting an emergent pattern of sustainable urban expansion. However, cities at the developmental extremes highlighted the need for optimizing urban development strategies. By categorizing YRD cities into four distinct development modes, our study offers deep insights into the dynamics of urban development, underpinning targeted strategies that could guide cities towards more sustainable and resource-efficient growth trajectories.

Reusing the building elements is the highest possible level of circularity for buildings that must be demolished, potentially slowing down climate change. This study explores the embodied carbon reduction of construction of a pilot building with structural elements of reused concrete. The assessment focuses on applying different methodological approaches and discussing the upscaling opportunities of reusing concrete elements from a global warming potential perspective. The assessment shows large embodied carbon savings compared to conventional building practices like recycling the concrete and building with new low-carbon and prefabricated elements. Embodied carbon saving is also obvious when applying alternative system modelling, future market projection and different allocation approaches of the production emissions of the elements. Finally, the study emphasises the need for further research in evaluating the benefits of reusing structural concrete elements broadly, like including the deconstruction impact related to elements for reuse, to be able to draw general conclusions.

Population migration is a key driver in reshaping the geospatial pattern of energy consumption and associated carbon emissions. However, the extent of shifts in the geospatial pattern and their primary drivers have not yet been quantitatively validated. We develop an integrated system and a novel structural decomposition analysis (SDA) method and for estimating the residential carbon emissions flows embedded in interprovincial population migration in China from 2010 to 2020. Interestingly, despite the significant increase in the scale of population migration between Chinese provinces (79.94 to 122.83 million), the net increase in carbon emissions due to population migration is decreasing (+23.42 to +5.16 Mt CO₂). Lots of rural-urban migration flows from inland to coastal areas shift from increasing carbon emissions in 2010 to decreasing carbon emissions in 2020. The SDA indicates that the primary driver behind the decline in residential carbon emissions can be attributed to urbanization (-20.82 Mt CO₂). Overall, this study can inform other developing countries on sustainable urbanization and geospatial management for energy decarbonization.

This study employs a life cycle assessment (LCA) to quantify the environmental impacts of three crumb rubber recycling technologies in asphalt rubber (AR) mixtures: wet, dry, and terminal blend. The analysis identifies key factors affecting their environmental performance across the life cycle. Results were characterized into climate change, stratospheric ozone depletion, fine particulate matter, terrestrial acidification, marine eutrophication, freshwater ecotoxicity, human toxicity, and Land use. Dynamic rankings of the three AR technologies along their life cycle stages in each impact category would enable identification of the influencing factors and provide reference for the further improvement. This study reveals that dry technology is likely to have the most significant environmental impacts across all categories (51.85 %-100 %), whereas terminal blended technology generally presents the lowest impact (51.85 %-88.89 %), with the exception of freshwater ecotoxicity (33.33 %) and human toxicity (22.22 %), where wet technology shows the least impact. The analysis underscores the importance of asphalt mixture designs, with appropriate binder content, potential reduction in surface course thickness, and reduced maintenance frequency, as strategies to enhance the environmental performance of AR technologies. The study concludes that the environmental performance of AR pavement is highly dependent on their in-service durability, with scenario-based analysis indicating that adequate durability ensures environmental effectiveness.

Hydrogen fuel cell is promising option for low-carbon transportation but poses concerns regarding potential emission increase in production activities. Limited by insufficient primary data, previous studies relied on incomplete material and energy inventory, leading to uncertain knowledge of life-cycle impacts of fuel cell. This study provided real-world data of material composition and in-plant energy demand for a refined evaluation of greenhouse gas (GHG) emissions and mitigation potentials of fuel cell. Result showed cradle-to-gate emissions of an 83.5 kW fuel cell applied to minivan were 5952 kg CO₂-eq, equally contributed by upstream materials production and in-plant electricity and hydrogen consumptions. By 2030, proposed low-carbon strategies are expected to mitigate 66% emissions. The impacts assessed here were higher than preceding studies, which disregarded or underestimated manufacturing stage inputs. It emphasizes the necessity of large-scale field surveys and meta-analyses to maturate accounting standard and refine life-cycle assessment of fuel cell in the future.

With the rise of global value chain (GVC), traditional accounting methods for virtual water (VW) trade have failed to reflect the inherent VW flow generated by the production of intermediate goods in shared production processes. Here, we reassess China's VW consumption in 2020 based on a new GVC framework, and propose the concept of VW consumption embodied in forward and backward GVC activities (VWF/VWB). We clarify China's role in GVC activities and reveal VWF/VWB inequalities under multiple scenarios. Our results show that the maximum share of VWF and VWB reaches 64.4% and 86.1%, respectively, far exceeding the traditional trade share. China's VWB primarily sources from developing countries in Asia, while VWF primarily serves the United States. VWF/VWB inequalities are exacerbated by China's GVC activities and exhibit considerable variation under multiple scenarios. Our findings provide new insights into reconciling China's GVC participation and narrowing regional disparities in VW consumption.

Textile production and consumption has been increasing over time, along with an increase in waste production. However, there is a substantial gap in knowledge about the textile flows. The European Union has set ambitious target in relation to circularity of the textile sector. Hence, it is essential to understand the complex system of textile production, consumption and disposal to identify the most effective pathways towards circularity. To the best of our knowledge, an overview of textiles flows throughout the whole EU textiles value chain, including both products manufacturing and end of life, remains elusive. To address this gap, this study presents a Dynamic Probabilistic Mass Flow Analysis (DPMFA) of textiles in the EU-27 in the year 2019 (reference year) and 2035 (baseline). It is estimated that annually 11 Mt of used and waste textiles are generated in the EU, of which approximately 80% are either incinerated or landfilled (8.5 Mt).

The escalating demand for refined copper intensifies research into the recycling of copper-based solid waste, exemplified by recovery of copper from waste enameled copper wires (WECWs). Despite its potential, the pyrolysis process for WECWs is hindered by embrittlement, diminishing both recycling yield and quality. Our study pioneers the elucidation of the embrittlement mechanism during WECWs pyrolysis through atom probe tomography and first-principles calculations, revealing that hydrogen, a byproduct of paint film pyrolysis, accumulates at copper grain boundaries, inducing embrittlement by reducing adhesion energy. We introduce two innovative strategies to mitigate hydrogen-induced embrittlement: vacuum pyrolysis and enhanced N₂ flow. These approaches significantly reduced hydrogen content from 11.1 % to about 5 % and increased elongation from 2.65 % to 15 %. Moreover, pyrolysis efficiencies of 92.79 % and 91.4 % were achieved, respectively, at temperatures 50 °C lower than conventional methods. Our findings provide crucial theoretical insights into embrittlement and offer effective recovery strategies for copper from solid waste.