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Knowledge gained from anthropogenic resource prospecting can shed light on the theoretical potential of secondary resources stored in anthropogenic systems. Among others, secondary resources accumulated in the built environment account for a big fraction of anthropogenic resources, indicating great potential for urban mining. However, realizing these opportunities and developing urban mining strategies will require a comprehensive understanding of the technical viability of urban mining technologies, and how their implementation will affect the technical, economic, and environmental performance of a construction and demolition waste (C&DW) management system. To address these important issues, this review summarizes (1) current and emerging technologies that can enable the transition from anthropogenic resource prospecting to anthropogenic resource mining, (2) Life Cycle Assessment (LCA) and Life Cycle Cost Analysis (LCCA) results to date on various C&DW management systems, (3) key parameters that govern the technical, economic, and environmental performance of a C&DW management system, and (4) opportunities for improving the methodology of LCAs and LCCAs for future C&DW management. We find that enhancing the utility of extant LCAs and LCCAs in guiding technology deployment and policy decisions can be achieved by considering key parameters governing the techno-economic and environmental performance of C&DW management. In addition, it is critical to adopt and upscale emerging technologies to increase the added value of materials or products recovered from C&DW., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

It has been observed that the massive urbanization has boosted up infinite construction in the developed as well as developing countries. The construction and demolition waste has been correspondingly increased enormously which results in nasty and fatal impacts on urban sustainability and survival in the term of economic values and environmental safety. Considering construction and demolition waste management (CDWM) in the USA and China and its comparison has not been discussed, this study explores some research questions to fill such gaps: What are the existing CDWM policies and regulations in these two countries? What is the market mode for CDWM? What are the key challenges of CDWM? What are the CDWM contribution and limitations toward circular economy? What are the lessons that must be exemplary for the two economies through mutual learning? Our results show that the CD waste generation and its management are influenced by several factors including population, urbanization, gross domestic product (GDP), and CDWM regulatory measures. The USA has more developed CDWM system. Whereas, China is a growing economy and it has some management deficiencies in the construction industry. Key suggestions for improving CDWM include: i. Government supervision along with an economic incentive approach, ii. Interaction between Stakeholders, iii. Mutual coordination among operational departments, iv. Audit and inspection setup, and v. Continuous development and integration of emerging technologies., Competing Interests: Declaration of competing interest There is no conflict of interest., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Construction and demolition waste (CDW) accounts for 30% to 40% of the total amount of waste in China. CDW is usually randomly dumped or disposed in landfills and the average recycling rate of CDW in China is only about 5%. Considering there is big challenge in adoption of circular economy in CDW industry in China while related research is still limited, we conduct the CDW management analysis through 3R principle. Existing policies and management situations were investigated and analyzed based on the reduction, reuse and recycle principles. Results reveal that primary barriers of reducing CDW in China include lack of building design standard for reducing CDW, low cost for CDW disposal and inappropriate urban planning. Barriers to reuse CDW include lack of guidance for effective CDW collection and sorting, lack of knowledge and standard for reused CDW, and an under-developed market for reused CDW. As for recycling of CDW, key challenges are identified as ineffective management system, immature recycling technology, under-developed market for recycled CDW products and immature recycling market operation. Proposals to improve the current situation based on 3R principle are also proposed, including designing effective circular economy model, reinforcing the source control of CDW, adopting innovative technologies and market models, and implementing targeted economic incentives. [ABSTRACT FROM AUTHOR]