Revolutionizing Wastewater Reuse: A Critical Review of Innovative Treatment Technologies for a Sustainable Energy-Water Nexus

The continuing rise in the global population has increased water demand, thereby intensifying pressure on water resources.As demand exceeds conventional sources, wastewater reuse has emerged as a critical solution.The reuse of treated wastewater, both in the domestic and industrial sectors, has significantly enhanced water security, reducing groundwater stress and energy requirements.Hence, due to the rapid advancement in wastewater treatment, a large volume of articles on techniques for increasing wastewater treatment efficiency and reducing energy costs has emerged.This paper explores the innovative treatment technologies and their integration into wastewater reuse systems in line with the energy-water nexus.Key innovative technologies such as forward osmosis, solar-driven desalination, electrochemical systems and nanotechnology methods, which offer improved treatment efficiency, energy savings and resource recovery potential, are highlighted.Moreover, this paper emphasizes the synergy of treatment technologies with renewable energy sources in demonstrating their significant potential in energy-efficient water recovery and reuse, thereby enhancing energy generation (such as biogas) and stabilizing water flux.The novelty of this work is to critically assess the next-generation wastewater treatment technologies that advocate for environmental sustainability and energy efficiency, thus ultimately contributing to a more resilient and integrated energy-water system.