Presentation and perspective of appealing green facilities for eco-cyclic water management

To tackle the various challenges and build a more sustainable living condition, a shift from conventional wastewater treatment systems to source recovery oriented and eco-friendly technologies is taking place. Green facilities (GFs) refer to some ecological engineered systems that mimic the natural processes to achieve wastewater purification with lower energy and chemical inputs. Moreover, the fantastic aesthetic value of the GFs makes them perfectly integrated with the surrounding landscape and thus readily accepted by residents. Thus, GFs represent a potential direction of the future wastewater treatment schemes. The present review retrieved and compiled the most representative GFs in the practice including food chain reactor, solar aquatic system (TM), Living Machine (R), Biomatrix and green walls/roofs as well as the newly emerging green bio-sorption reactor (GBR). The concept and performance of each GF were discussed and compared to present a rough image of their superiority. Moreover, an eco-cyclic water management scheme was proposed with the GFs involvement.