Growing wastewater volumes and intensifying water scarcity are driving the need for affordable, sustainable solutions that enable safe urban water reuse and strengthen climate resilience. Policy frameworks such as SDG6 and EU water reuse requirements highlight that reclaimed water must meet strict environmental and public health standards. In contrast, conventional biological treatment cannot fully remove many emerging contaminants, underscoring the need for advanced treatment approaches that consistently deliver high-quality reclaimed water. In this context, this review examines the role of membrane technologies (MF, UF, NF, RO, FO) and membrane bioreactors (MBRs) in providing safe water in urban environments and in enhancing urban climate resilience, including decentralized systems and advanced reclamation needs. It also discusses the contribution of membrane-based solutions to sustainable cooling systems and heat-stress mitigation, as well as the integration of membrane technologies into green infrastructure and nature-based solutions for climate adaptation. Technical and economic performance is shaped by fouling, cleaning requirements, and energy use, making life-cycle and operational optimization critical for long-term sustainability. Case studies and EU-funded initiatives demonstrate that, with appropriate governance and design, membrane-based approaches can enable reliable reclaimed water supply, enhance water security, and contribute to circular urban water management. The analysis was based on peer-reviewed open-access publications, which may introduce a degree of selection bias.

The transition to climate neutrality necessitates a profound transformation of mining systems. In this context, this study focuses on reviewing the role of circular economy models in transforming mining systems. Circular models propose reconfiguring systems into climate-neutral and more resource-efficient configurations. A synthesis of recent literature highlights several circular strategies frequently addressed throughout the mining life cycle. These include waste recovery, secondary resource recovery, water reuse, and the integration of renewable energy. The outcomes of circular approaches have the potential to reduce greenhouse gas emissions and resource consumption. They can also help improve the system’s efficiency through the creation of new economic value streams. Large scale implementation remains constrained because of economic, technological, and governance factors. In light of these findings, the paper recommends an integrated conceptual framework. It ties circular strategies to decarbonization pathways and sustainability outcomes. It does so because the circular economy is not merely a supporting approach but a necessary mechanism to enable the transition to climate-neutral and regenerative mining systems.