Aeration Strategies in the Treatment of Effluents from a Pig Slaughterhouse Using Sequential Batch Reactors (#1591)

Authors

Carrasquero Ferrer, Sedolfo Jose

Abstract

For the animal slaughter industry, water is used before, during and after the slaughter process and the effluents generated are an important source of pollution. In this research, the removal efficiency of organic matter, nitrogen and phosphorus was compared during the treatment of effluents generated in a pig slaughterhouse, applying two aeration strategies: nitrification – conventional denitrification (NDC) and intermittent aeration (AI). Two laboratory-scale sequential loading cylindrical reactors were used, with a volume of 4 L, which operated in parallel using an anaerobic/aerobic/anoxic (An/Ae/Ax) and an An/Ae1/Ax1/Ae2/Ax2/Ae3/Ax3 sequence, which corresponded to the two aeration strategies applied. The parameters measured at the beginning, during and at the end of each evaluated cycle were chemical oxygen demand (COD), biochemical oxygen demand (BOD5.20), total Kjeldahl nitrogen (NTK), pH, total alkalinity, orthophosphates and total phosphorus (PT). The effluents were characterized by having a COD of 6773 mg/L, a BOD5.20 of 2208 mg/L, and a TN and TP content of 348 and 17.9 mg/L, respectively. It was found that for both aeration strategies, average values ​​of 95 and 87% removal were achieved for BOD5.20 and COD, respectively. Likewise, the aeration strategies evaluated were equally effective in removing nitrogen and phosphorus, obtaining average removal percentages of 71 and 52%, respectively. The NDC strategy was selected for the treatment of the chamber effluents, because the AI ​​strategy requires greater control in the reactor during its operation.