The performance of a polishing pond for treating swine wastewater from an upflow anaerobic sludge blanket (UASB) reactor was evaluated. The system was assembled with a slat settler, followed by an UASB reactor, on a real scale, and a post-treatment pond, on a demonstration scale. The following parameters were analyzed: temperature, pH, biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), volatile suspended solids (VSS), total Kjedahl nitrogen (NTK), ammonia nitrogen (N-am.), organic nitrogen, total phosphorus, and total and thermotolerant coliforms. The polishing pond was highly efficient, removing an average of 58.9% of BOD, 60.1% of NTK, 57% of N-am., and 95.34% of thermotolerant coliforms.
swine wastewater; polishing pond; UASB reactor