Evaluation of the Performance of a Polishing Pond With Baffles in Domestic Wastewater Treatment: Effects of Hydraulic Retention Times

Objective: The objective of this study is to evaluate the performance of a shallow polishing pond, with a depth of 0.40 m and baffles, in treating domestic wastewater from a UASB reactor, operating under three different hydraulic retention times (HRT): 10, 5, and 3 days. Theoretical Framework: The research is based on theories and models of wastewater treatment using stabilization ponds, which are influenced by operational and climatic factors, with an emphasis on polishing ponds for pollutant removal. Method: The pond was developed on a pilot scale, and pollutant removal efficiency was evaluated based on different HRTs. Parameters such as E. coli, total nitrogen, and ammoniacal nitrogen removal, as well as phosphorus removal, were analyzed. Results and Discussion: The best results were observed at 10 and 5-day retention times, with E. coli removal rates of 99.99% and 99.97%, respectively. Total nitrogen removal was most efficient at 5 days HRT (73.5%), and ammoniacal nitrogen showed removal rates of 73.6% at 10 days HRT and 82.8% at 5 days. Phosphorus removal was consistent, with an average of 43.44%. Research Implications: This study provides valuable insights for the optimized operation of polishing ponds, suggesting that HRTs (Hydraulic Retention Times) between 5 and 10 days maximize system efficiency. Originality/Value: The research contributes by demonstrating the operational efficiency of shallow ponds with baffles, highlighting the removal of pathogens and nutrients in domestic wastewater.