Performance of the sequencing batch reactor to promote poultry wastewater nitrogen and COD reduction

Resumo

Nitrification and denitrification of poultry wastewater treated in a sequencing batch reactor was studied. The reactor was constructed with a glass tube, having a useful volume of 4 L, with a jacket for temperature control, and with porous stone at the bottom to promote aeration. The experimental results showed that the best operational strategy occurred when the following conditions were used: 500 mL of thickened sludge to simulate the treatment end, feed flow rate of 1.1 L/h, dissolved oxygen concentration of up to 5 mg/L during the aerobic reaction, and next to zero at the anoxic phase. Thus the cycle consisting of the following phases: 4 h aerated fill, 7.25 h aerated reaction, and 1 h settling. In this conditions, the reduction of ammonia, nitrite, nitrate, COD, and phosphorus were 87%, 67%, 75%, 74% and 86% at 25oC, respectively.