METHOD OF COMMONLY TREATING COMMUNAL AND SUGAR MILL WASTE WATERS AND TREATMENT PLANT THEREFOR

摘要

1. Treatment method for combined municipal and sugar-processing wastewater in a two-stage process, characterized in that tradewaste from sugar processing is digested anaerobically to reduce BOD5 by 80 û 85 percent while municipal sewage is treated in the Stage 1 with the high-rate activated sludge process with organic loadings of 2 - 8 kg BOD5 /kg dry solids per day, achieving through aeration reduction of BOD5 by 60 û 70 percent; after separation of sludge the municipal effluent is mixed with the sugar processing effluent, obtaining mixed effluent of BOD5 in a range of 150 - 300 g/m3, and this combined effluent is further treated in Stage 2 with activated sludge at low loadings of 0.15 - 0.30 kg BOD5 /kg dry solids per day, achieving through aeration reduction of BOD5 to the maximum of 12 g/m3, while excess sludge from both Stages is combined, thickened to 96 percent and digested anaerobically, and at both treatment stages flexible, independent recirculation of sludge is maintained.4. Treatment plant for combined municipal and sugar-processing wastewater, characterized in that consists of trunk municipal sewer (1), screens (2) and grit chamber (3), and aeration tank for Stage 1 (4) that are connected to the intermediate sedimentation tank (5) equipped with the sludge recirculation pipe (6), and intermediate sedimentation tank (5) is connected through the mixing tank (12) with the aeration tank for Stage 2 (14), while the mixing tank (12) is connected to the anaerobic digester (10), while the aeration tank for Stage 2 (14) is connected through the secondary sedimentation tank (15) to the effluent discharge, and the secondary sedimentation tank (15) is equipped with sludge recirculation pipe (16)[...]IMAGE