A Survey on Nitrogen and Phosphor Compound Variation Processes in Wastewater Stabilization Ponds

摘要

Being economical has increased utilization of stabilization ponds to remove different contaminants from wastewater in proper weather conditions. Our current study investigates variations of nitrogen and phosphorous compound concentrations in effluent of wastewater stabilization ponds. 60 samples were taken from raw wastewater, anaerobic pond (AP) effluent, primary and secondary facultative ponds (PFP and SFP), and effluent of final ponds in weekly intervals for 3 months. Samples were examined based on standard methods (20th edition) for the examination of water and wastewater. Nitrogen kjeldahl removal output due to the AP, PFP, SFP, and the whole system were 20.6±4.9, 6.6±3.4, 13.4±9.5, and 47.7±9.1%, respectively. Nitrite removal output due to the PFP, SFP, and the whole system were 30.1±8.8, 36.3±9.8, and 58.8±5.2%, respectively. Respective values for phosphor removal output in AP and SFP, and the whole system were 21.8±10.3%, 13.3±10.1%, and 20.9±17.1%. However, nitrite concentrations in all samples from AP effluent and phosphor levels in all samples from PFP effluent increased compared with those of influent. The results showed that AP plays an important role in removal of organic nitrogen and phosphorous compounds. While the whole system output in nitrogen compound removal was 58.8±5.2%, phosphor removal output showed low efficiency (20.9±17.1%). Increasing the number of complete ponds is suggested for increasing phosphor removal efficiency.