Recent development of wastewater treatment technologies towards sustainable energy recovery, environmental protection and circular economy

The global wastewater treatment (WWT) sector is undergoing a fundamental paradigm shift from simple pollutant removal to becoming a core node within the water-energy-carbon nexus. This study provides a comprehensive decadal synthesis of advanced WWT technologies, evaluating their environmental, economic, and operational impacts through a systematic bibliometric analysis. The analysis identifies a strategic transition toward integrated biorefinery models and decentralized resource-mining hubs to achieve global carbon neutrality. A key innovation is the integration of an intelligence layer comprising artificial intelligence and digital twin technology to optimize energy-intensive processes, with pilot data demonstrating energy savings of 20–30%. Furthermore, the synthesis evaluates the synergistic potential of hybrid architectures, including photosynthetic microbial fuel cells, anaerobic membrane bioreactors, and green nanotechnology, which facilitate the concurrent mineralization of recalcitrant pollutants and renewable bio-energy generation. Despite these advancements, the study highlights critical techno-economic paradoxes, specifically the high electrical demand for persistent contaminant destruction such as PFAS relative to carbon-neutrality goals. To conclude, this research provides a strategic technical roadmap for transforming WWT infrastructure into resilient, energy-independent circular hubs capable of meeting 2030 sustainability goals.