Design of modular constructed wetland and its effect on rural domestic sewage treatment

Abstract According to the characteristics of large amount and scattered discharge of domestic sewage in rural residential environment, a rural domestic sewage treatment system based on modular constructed wetland was designed. The wetland is composed of three modules with a treatment scale of 30 m3/d. The plants are Arundo donax and Typha, and three kinds of filter media are selected to fill the substrate. The treatment capacity and treatment effect of the modular constructed wetland were studied through experiments. The results showed that the modular constructed wetland had a good treatment effect on sewage, and the average removal rates of BOD5, COD, SS, NH3-N, TN and TP were 83.3%, 83.5%, 90.5%, 70%, 66.9% and 68.3%, respectively. The treated water quality can meet the first class standard of water pollutants discharge standard for rural domestic sewage treatment and disposal facilities (DB37/3693-2019) of Shandong Province. The modular constructed wetland can be used to treat rural scattered domestic sewage with strong applicability, flexibility and feasibility.