Constructed wetlands applied on domestic wastewater for decetralized systems: concepts, processes, modalities, combinations and enhancements; a review

Constructed wetlands (CWs) are ecosystems artificially designed to mimic natural wetland systems for the treatment of effluents. Its adoption can be given both at a decentralized level and as an economic alternative for a variety of pollution controls: agricultural, industrial, mines and urban drainage effluents. Although a CW has larger area requirements than conventional energy-intensive treatment technologies, they have several advantages: lower costs; energy savings; fewer operating and maintenance requirements; enable wild habitat and natural leisure areas; and allow the use of solar energy. Thus, the treatment of effluents through CWs is highly promising. This review aims to encompass the current literature and state-of-the-art on CWs applied on domestic wastewater in decentralized systems, explaining with visual examples their constructions, processes and modalities.