Effect research of nitrogen removal out of sewage in constructed wetland

This research, in selection of constructed wetland system planted with reeds and cattails, takes vertical and horizontal flow experiment for study of TN removal out of sewage in various temperatures and waterpower length of stay. The effect and ratio of removal of sewage TN, ammonia nitrogen can be approached. The test shows that, temperature and TN removal have some correlativity, namely, the TN removal in summer goes high above 72%, and lowers below 48% in fall; As hydraulic retention time lasts at the 6^th day, the TN removal goes up to the highest of 55.32%, and the removal ratio falls with the prolonging of residence time; The constructed wetland system with vertical flow generates TN removal ratio (68.2~72.2%) exceeding slightly the ratio in the horizontal flow system (66.9~72.0%); The removal capability in wetland of reeds exceeds distinctly that in wetland of cattail.