Application of hybrid systems to the treatment of meat industry wastewater

The study aimed to assess the effectiveness of meat industry wastewater treatment applying two hybrid systems of activated sludge and ultrafiltration in: (1) an aerobic bioreactor in combination with ultrafiltration and (2) a bioreactor equipped with separate denitrification and nitrification tanks in combination with ultrafiltration. It was found that it is feasible to treat this wastewater in both systems; however, the aerobic bioreactor necessitated the use of a very low activated sludge loading of 0.017 gCOD/gTS×d. Consequently, the bioreactor equipped with separate denitrification and nitrification tanks proved to be more favourable. The substrate loading of 0.15 gCOD/gTS×d, aeration intensity of 800 dm3 and constant activated sludge loading of 4 g/dm3 were used in this system. The wastewater treated under these conditions satisfied the requirements of the Regulation of the Minister of the Environment of 8 July 2004 and could be discharged into receiving water.