Constructed Wetland (CW) Technique as an Effective Sustainable Treatment for Wastewater: A Review

Wetland's concept are becoming a popular alternative to traditional technologies for processing wastewater from domestic as well as industrial, especially for tertiary treatment of wastewater. Constructed Wetland (CW) is the assemblage which performs the treatment of wastewater by the process of unit operation techniques using natural process. It helps in achieving effective treatment efficiency in a sustainable manner. Due to an increase in wastewater loading, insufficient arrangement of sterilization and sewage treatment prompts in ecological impact and contamination of water bodies. It leads to water stress and depletion of good quality of ground water. Therefore, wastewater and reusing techniques will be essential in the coming days to overcome the crisis. CW is an effective alternative to overcome this situation. CW systems seem to be viable alternative in treating predominantly domestic wastewater and some type of industrial wastewater. In this method, the readied wet soil is successful for eliminating natural and suspended solids, while the evacuation of nitrogen is moderately low, however, can be improved by utilizing a combination of various sorts of wet soil arranged to satisfy water system reusing guidelines. In this research study, feasibility analysis has been carried out with domestic wastewater and industrial wastewater to ascertain the efficiency of CW in treating the wastewater and also the problems and limitations in handling the same was also assessed. General instruction regarding CW operation built for the treatment of specific wastewater types also ascertained in this research study. The important points that should always include suggestions about the pre-treatment stage, plants, and permeable media and built wetland operation strategies, etc., are discussed in this research paper. CW with integrated/hybrid model by linking both horizontal and vertical flow units was fabricated in a lab-scale hybrid wetland unit for treating the wastewater. Based on several trail study, it was observed that CW are very effective in treating organic wastewater. The treatment efficiency of some of the common parameter like Biological Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) was around 70-80%. Several researchers have also proved that this one of the viable alternative technique for urban environment and semi-urban environment were availability of space for developing the CW unit is not a problem. It was evident from the study that CW is effective sustainable technology for the near future to solve the water crisis and to implement 3R concept in wastewater treatment.