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Abstract Improving the eco-efficiency of the circular economy system in mining areas has been recognized as the most effective way to reduce the greenhouse effect and achieve sustainable development. Based on the emergy theory and on data envelopment analysis (DEA), this paper adopts the SBM-Undesirable model to evaluate the eco-efficiency of the circular economy system in China's largest coal mining area, Shanxi Province, during the period 2006–2015. Emergy flow indices are treated as input and output indices. Eco-efficiency is factorized into economic efficiency and environmental efficiency. The potential for improvement of the circular economy system is analyzed based on input redundancy and output deficiency. The results for the period 2006–2015 indicate the following: (1) both the input and the output of the circular system increase during this period; (2) the increased input relies on mostly imported emergy, and the increase in waste emergy is lower than the exported emergy; (3) eco-efficiency is invalid except for 2011 and 2012 and exhibits a decreasing trend beginning in 2013; (4) environmental efficiency is invalid over the entire period, and the eco-efficiency level is positively related to the economic efficiency score; and (5) the circular economy system has a larger energy saving space, and the key to achieving sustainability of the circular economy system is output growth. Highlights • We assess the circular economy system eco-efficiency of coal mining in China using emergy and DEA. • We decompose eco-efficiency as economic efficiency and environmental efficiency. • The circular economy system is an energy-intensive system with high input and output. • The eco-efficiency level is positively related to economic efficiency. • The circular economy system has huge potential to save energy and reduce emissions. [ABSTRACT FROM AUTHOR]

The need for circularity assessment tools to prevent undesirable effects (e.g. recycling processes requiring more energy) is gaining recognition. Preserving resources and relieving pollution reservoirs are both necessary conditions to achieve a sustainable circular economy (CE), and the corresponding assessment tools should be selected accordingly. We chose life cycle assessment (LCA) and the Material Circularity Indicator (MCI). In this paper, we tested the tools through two case studies from the tire industry. The Brazilian case proposes three scenarios to process used tires: baseline, retreading and regrooving. The European case suggests collecting secondary material from end-of-life (EoL) tires to produce recycled content (RC) at 4% and 10% rates. These rates were chosen to illustrate the change in tire performance in the use phase. We propose an approach to discuss MCI and LCA results that identifies four pathways toward or away from the CE goal: coupling, decoupling, trade-off on resources or trade-off on reservoirs. The case studies reveal that extending lifetime through retreading and introducing recycled material improves the MCI of a tire but do not necessarily improve impacts on human health and ecosystems. Also, discrepancies in the results between the MCI and the LCA's resource indicator highlight relevant issues for new CE experts seeking to design assessment tools. Even though LCA provides a broader scope than the MCI, it still reflects a relative contribution to environmental sustainability while the MCI focuses on micro-scale improvements in resource use efficiency. [ABSTRACT FROM AUTHOR]

The regional level has been recognized as a good scale for implementing actions towards sustainable development (SD). An important pathway to improve regional sustainability is to locally carry out long-term ecological planning. In order to reduce environmental impacts from fast economic growth, several eastern provinces of China began Ecological Province Construction (EPC) at the end of 1990s. This paper presented a case for analyzing the progress of EPC in China via both qualitative and quantitative methods. We studied Shandong Eco-province Construction (SEPC) and evaluated its outcomes with its pre-set indicators in 2003–2010. A further evaluation with eco-efficiency and de-linking indices was conducted. The results indicated the pre-set indicators could not effectively reflect of the ecological province construction. It was recommended to introduce an evaluated framework combined with eco-efficiency and de-linking indices to indicate ecological planning at the regional scale. [ABSTRACT FROM AUTHOR]