Mechanism and Application of Constructed Wetlands in Sewage Treatment

Abstract

In recent years, with the increasingly serious problem of global water pollution, constructed wetlands with high efficiency, high adaptability and low cost, as an effective wastewater treatment technology has been widely studied and applied. This article mainly introduced the common types of constructed wetlands, including surface flow constructed wetlands, subsurface flow constructed wetlands and a variety of composite constructed wetlands, and the mechanism of microorganisms, plants and substrates in constructed wetlands. Differently constructed wetlands are suitable for different scenes. It can be seen from the data that the constructed wetlands with different compositions have good effects on the removal of chemical oxygen demand (COD), biochemical oxygen demand (BOD), total nitrogen (TN), total phosphorus (TP), ammonia nitrogen (NH4+-N) in sewage. Microorganisms have good removal and transformation effects on nitrogen and phosphorus, and the application of biofilm technology also has good prospects and value. Plants can be used in the absorption and transformation of heavy metals. The adsorption of the matrix is mainly a physical process, which uses its loose porous and large specific surface area to adsorb pollutants. Artificial wetlands have a positive impact on sewage treatment and are conducive to the construction of ecological civilization.