Improving Vertical Flow Constructed Wetlands with Novel Filter Materials to Treat Wastewater

Summary

Reuse of treated wastewater is limited by the inefficiency of the existing technologies to remove various pollutants, especially micropollutants (e.g. pharmaceuticals and pesticides). We developed a compact, nature-based, post-treatment technology called improved vertical flow constructed wetlands with hydroponic materials (CWH) which is composed of hydroponic materials, cocopeat, mineral wool and pumice, planted with ornamental plants, Syngonium and Periwinkle. Mesocosm CWH was constructed and fed with pre-treated wastewater. CWH of cocopeat significantly removed various micropollutants including the most persistent ones (e.g. carbamazepine and diclofenac) with above 80% of removal efficiency. CWH of pumice facilitated simultaneous nitrification and denitrification processes and Syngonium plant enhanced the total nitrogen removal. Cocopeat and pumice also exhibited the potential of removingpathogens, P. aeruginosaandE. colifrom wastewater. Superior performance of CWH over typical constructed wetlands creates new opportunities for the application at large scales to produce reusable (waste) water.