查看更多>>摘要：Environmental regulation is a critical instrument for achieving sustainable economic and social development in the context of carbon neutrality. The iron and steel industry is highly polluting and energy-consuming, posing a significant threat to China's environmental sustainability. Based on the panel of Chinese provincial-level data from 2000 to 2017, this paper empirically examines how environmental regulation affects the iron and steel industry's green development. The findings show that there is a U-shaped relationship between environmental regulation and energy-environmental performance. Low environmental regulation intensity inhibits the improvement of energy-environmental performance. But as the regulation intensity increases, it contributes to the advancement of energy-environmental performance. Environmental regulation affects the industrial energy-environment performance through technological innovation, and the relationship between environmental regulation and technological innovation presents a U-shaped relationship. There are noticeable regional differences in the impact of environmental regulation on energy-environmental performance. The findings provide new evidence to confirm the Porter Hypothesis. Finally, this paper provides policy suggestions for further energyenvironmental performance improvements in China's iron and steel industry.
查看更多>>摘要：Elimination of alloying elements in the end-of-life (EoL) zinc-based products is essential for the resource efficiency of zinc recycling. Using a thermodynamic method, the elimination behavior of 34 alloying elements during the recycling of EoL zinc-based products by the remelting process was quantitively evaluated. The influence of all the thermodynamic parameters was considered and extensively discussed. It was found that the remelting process with treatment using chloride flux or oxide slag is efficient in alloying elements elimination. However, eliminate alloying elements, such as antimony, bismuth, cadmium, cobalt, copper, germanium, gold, indium, iron, lead, nickel, silver, and tin is difficult. These elements will contaminate the remelted zinc metal once mixed in the collected EoL products. Moreover, promoting the elimination of these alloying elements is difficult by adjusting the remelting conditions such as temperature, chlorine partial pressure, and flux composition. To increase the recycling efficiency of zinc, in addition to improving metallurgical refining technology, establishing an advanced recycling system to achieve a horizontal alloy-to-alloy recycling and changing the current trend of product design of excessive mixing is essential. The thermodynamic criteria of alloying elements elimination can provide basic information for these tasks.
Okuyama, AkihiroYoo, SunbinKumagai, JunyaKeeley, Alexander Ryota...
11页
查看更多>>摘要：Reaching carbon neutrality would require the retirement of conventional power sources and substitution with renewable energy sources. Given that immediate substitution from conventional to renewable power sources is not feasible in the status quo, we investigate whether adding residential solar photovoltaic (PV) technology in addition to conventional power sources would reduce residential emissions. We use a large survey dataset of more than 300,000 observations and employ a structural equation model (SEM) to validate our findings. Interestingly, emissions increase by 1.75% if residential PV is adopted, and Japanese citizens with residential PV systems end up using 3.02% more electricity. We also find that pro-environmental consumers may also produce more emissions with PVs. As a result, reaching target carbon reductions in the residential sector would necessitate eliminating conventional energy sources. We address the policy implications for pathways to reduce residential emissions.
Maier, JasonPalazzo, JosephSteigerwald, Douglas G.Geyer, Roland...
12页
查看更多>>摘要：Recently, California has made large investments in wastewater recycling to replace applications that use potable water. It may be expected that the use of recycled water reduces potable water use, but such an equivalency is not assured. The addition of recycled water infrastructure in a large Californian water district creates a natural experiment where this work tests how recycled water usage affects primary potable water. This is done using econometric methods for causal inference in an observational setting that mirror a randomized control trial (RCT). From 2001 to 2014, a number of public parks were given recycled water infrastructure, while others in those regions remained exclusively on potable supply. A two-way fixed effects regression is used to produce a difference-in-differences estimate of the average treatment effect of recycled water on total and potable water usage. The results indicate that potable water usage is reduced significantly when a park is connected to the recycled water supply. The estimated rate of displacement in the study period is 81.7%, meaning each unit of recycled water use avoided 0.817 units of potable water usage, which implies the connection of parks to recycled water supply increases total water use. The analysis provides, to the best of our knowledge, the first empirical estimate of the water savings claimed by urban water recycling programs, and the first empirical estimate of displacement using quasi-experimental methods. The methodology can be utilized to evaluate the effectiveness of recycling programs around the world.
查看更多>>摘要：Food waste produces methane in landfills, accounting for 1.5-2.0% of net global anthropogenic greenhouse gas emissions in 2010. In developing countries 40-65% of household waste can be food waste, especially from preparation, since pre-prepared food is less common. Different waste management strategies are used worldwide to get householders to separate out their food waste, including the restriction of permitted times and places for depositing household waste (e.g. 6-7pm daily at kerbside, only). Here we evaluate a Certain Time, Certain Place (CTCP) intervention used across a sample of six communities randomly allocated from a cohort in one district of Shanghai. Mixed methods are used, with directly-measured tonnages pre- and post-implementation, and site observations and open interviews of stakeholders to elicit perceived relevant factors. Quantitative results show no statistically significant impact on waste sorting performance. Relevant themes which emerged are: time period arrangements; supervision of waste stations; attitude of the assistant cleaners. These are shown to be related to known determinants of Inconvenience, Role clarification, and Positive interactions. Action Planning and Stakeholder Engagement are suggested as mitigators of Inconvenience, but Distance not found relevant. Such deconstruction of policy elements into scientific factors allows a clear scientific perspective: that this CTCP program was almost pure CT only, which increased Inconvenience without giving overall benefits from increasing supervision. Only one community had CP involved, and its performance increased significantly, suggesting CP should be studied further. In sum, this Certain Place, Certain Time recycling program was actually CT, and is not recommended for increasing food waste sorting performance. The more direct linking of policy elements to scientific factors is suggested as useful for better future design.
查看更多>>摘要：Excessive phosphorus emissions by anthropogenic activities are closely related to eutrophication in the Yangtze River. Quantitative spatial distribution of total phosphorus (TP) emissions and identifying their driving forces are important for the management of phosphorus pollution in the Yangtze River Economic Belt (YREB). In this study, anthropogenic TP emissions were estimated using emission factors in the YREB for 2017. Global and local spatial autocorrelation and multiple regression analysis were adopted to reveal the spatial agglomeration effects and driving forces of the TP emissions in 130 cities of the YREB. The TP emissions were estimated to be 155,940 t, and the agricultural TP emissions were 106,181 t, followed by domestic (46,032 t) and industrial emissions (3727 t) in 2017 in the YREB. Livestock breeding was the most significant anthropogenic source of TP emissions. The TP emissions in the middle and lower reaches were larger than those in the upper reaches. A significant spatial agglomeration effect of TP emissions was found in the YREB, with High-high aggregation in the middle reaches and Low-low aggregation in the upper reaches. The paddy land area was the most significant factor affecting TP emissions, followed by the population size and vegetable orchard area. The results provide fundamental data regarding pollution sources for subsequent research investigations. The results enhance the understanding of the TP source contributions; thus, accurate control measures could focus on the important sources and regions of TP pollution in the YREB.
查看更多>>摘要：The agri-food sector is one of the key sectors where the action is needed to ensure the transition to a more sustainable development model in line with the principles of the circular economy (CE). The use of indicators to monitor progress and areas for action is a key element in the shift of companies, regions, and countries toward a circular model. This study aims to create a dashboard that can be used at various spatial levels to guide the agri-food sector toward a CE and sustainable development. Starting with the relevant literature, we identified 102 indicators classified according to three areas of sustainability (environmental, economic and social) and spatial dimensions (macro-meso-micro) within 8 scopes. The dashboard provides a toolbox for directing decision-making processes and strategies through the targeted use of indicators with respect to the context in which the CE is applied. In addition, the dashboard allows us to highlight missing aspects related to (1) new indicators not covered by the tool; (2) new scopes not yet explored in the literature; and (3) the need to adopt cross-sectional indicators. For this last aspect, the analysis revealed only 17 such indicators. A future step is to define the most suitable configurations among the indicators in which CE is generated, starting from the test of the indicators at the micro level to validate their applicability and consider the impacts they may have at the macro or meso levels.
查看更多>>摘要：The approaching end-of life phase of early installed PV modules gave rise to a variety of potential end-of-life strategies, ranging from basic generic waste management strategies to advanced case-specific recycling options. However, no comprehensive assessment on the full range of technological possibilities is available and only limited attention was given to the material recovery rates of these different technologies in light of circular economy. In addition, current material recovery rates are indifferent towards the material value and the value of their secondary applications. Based on an extensive literature review, ten end-of-life scenarios with potential learning effects are identified and their material flows are quantified using a combined material and substance flow analysis. Subsequently, material recovery rates from a mass, economic value and embodied energy perspective are calculated, incorporating the differences in secondary applications. The differences in the mass-based recovery rates of the seven end-of-life scenarios that did not have landfill or municipal waste incineration as the main destination were minimal, as 73-79% of the mass was recovered for the best-case learning scenario. For the economic value recovery rate (9-66%) and the embodied energy recovery rate (18-45%), more profound differences were found. The collection rate was identified as most crucial parameter for all end-of-life scenarios, learning scenarios and recycling indicators. The mass-based recovery rate might favor end-of-life scenarios that lead to dissipation of valuable materials in non-functional secondary applications. Additional targets are required to avoid cascading of valuable materials and to avoid the economic cost and environmental burden of virgin materials.
查看更多>>摘要：In response to climate change, the Chinese government has set a clear goal to reach its carbon peak by 2030 and achieve carbon neutrality by 2060, endeavoring to gradually realize net-zero carbon dioxide (CO2) emissions. This paper explores the concept of carbon neutrality and makes a comparative analysis of the gap between China, the European Union, and the United States vis-`a-vis carbon neutrality based on international data. The main challenges China faces in its progress toward carbon neutrality are the following: first, China's energy consumption and CO2 emissions continue to increase, while its carbon peak has not yet been reached; second, carbon emission reduction in China is an arduous process, as the transition period allowed for the country to transition from its carbon peak to carbon neutrality is shorter than that of developed countries; third, China remains reliant on high-carbon fossil energy, with high energy consumption and low energy utilization efficiency; fourth, China's low level of economic development, compared with those of the EU, the US, or other developed countries, makes it relatively weak to withstand economic risks; and fifth, China's low-carbon and zero-carbon technologies are not mature. Therefore, this paper posits a three-stage/four-step strategy as well as seven specific suggestions that could benefit China's progress toward carbon neutrality.
NSTL
Elsevier