To examine treatment and remediation of a wastewater lagoon with poor biodegradability, a typical wastewater lagoon in Tianjin, China, was treated and remedied using microelectrolysis and modified demand aeration tank...To examine treatment and remediation of a wastewater lagoon with poor biodegradability, a typical wastewater lagoon in Tianjin, China, was treated and remedied using microelectrolysis and modified demand aeration tank （DAT）/intermittent aeration tank （IAT） methods. After pretreatment by microelectrolysis, the removal efficiency of chemical oxygen demand （COD） was up to 64.6% and the ratio of BOC/COD in the effluent increased from 0.013 to 0.609. The removal rates of CODcr and NH4＋-N were affected by sludge backflow rate, mixed liquor suspended solids （MLSS）, and hydraulic retention time （HRT） in the modified DAT/IAT reactor. The highest removal rates of CODcr and NH4＋-N were up to 78.9% and 62.6%, respectively, when the sludge backflow rate was 38.0 mL/min, the total HRT was 8.0 hr and MLSS was 4088.0 mg/L. In this case, some protozoa and metazoa were observed in activated sludge and biofilm carriers. Most of chrominance was removed by microelectrolysis treatment, while the modified DAT/IAT methods were more effective for CODcr and NH4＋-N removal.展开更多
基金supported by the Tianjin Committee of Science and Technology as a Special Innovative Project (No. 08FDZDSF03402)the National Hi-Tech Research and Development Program (863) of China (No.2007AA061201)the Open Fund Project from the Key Laboratory of Pollution Process and Environmental Criteria (Ministry of Education),Nankai University,China
文摘To examine treatment and remediation of a wastewater lagoon with poor biodegradability, a typical wastewater lagoon in Tianjin, China, was treated and remedied using microelectrolysis and modified demand aeration tank （DAT）/intermittent aeration tank （IAT） methods. After pretreatment by microelectrolysis, the removal efficiency of chemical oxygen demand （COD） was up to 64.6% and the ratio of BOC/COD in the effluent increased from 0.013 to 0.609. The removal rates of CODcr and NH4＋-N were affected by sludge backflow rate, mixed liquor suspended solids （MLSS）, and hydraulic retention time （HRT） in the modified DAT/IAT reactor. The highest removal rates of CODcr and NH4＋-N were up to 78.9% and 62.6%, respectively, when the sludge backflow rate was 38.0 mL/min, the total HRT was 8.0 hr and MLSS was 4088.0 mg/L. In this case, some protozoa and metazoa were observed in activated sludge and biofilm carriers. Most of chrominance was removed by microelectrolysis treatment, while the modified DAT/IAT methods were more effective for CODcr and NH4＋-N removal.
