Abstract
Population growth, climate change, and unsustainable water use have prompted the exploration of alternative solutions for sustainable water management. While significant advancements have been made in resource recovery technologies from wastewater, the large-scale implementation of these systems and associated impact on the environment and society are still far from full realization. This paper reviews the scientific state-of-the art on resource recovery in the water sector with respect to the four pillars of symbiotic circular economy solutions, consisting of technological processes, final applications, business models, and stakeholder involvement. A systematic and transparent literature review has been carried out, showing that a variety of technologies for recovering water, materials, energy, and nutrients have been proposed and tested, but widespread application is constrained by multiple barriers. These include the technical limitations of existing recovery processes, financial obstacles, and the difficulties associated with integrating technologies into existing value chains. This work emphasizes the need for additional research on novel approaches to promote alternative business models and bottom-up involvement of stakeholders, from public and private organisations to local communities, in the planning and implementation of resource recovery systems in the water sector.