| Title |
Removal of Nitrogenous Compounds in Synthetic Wastewater Using - Three - stage Biological Fluidized Bed |
| Authors |
김환기 ; 권문선 ( Hwan Gi Kim ; Moon Sun Kwon ) |
| Abstract |
The substrate utilized in this study is a synthetic wastewater similar to septic tank effluents containing a considerable amount of nitrogenous compounds. The processes for the removal of nitrogen consist of nitrification and denitrification. The carbon source needed in denitrification and the oxygen and the alkalinity required in nitrification are important in the process for the removal of nitrogen. In order to reduce the treatment cost, a three-stage Biological Fluidized Bed reactor as an Anoxic-Aerobic-Anaerobic process was conceived. The efficiency and the rationality for the removal of nitrogen in wastewater using this reactor are discussed. The results obtained by varing the recycle ratio, the hydraulic retention time and the recirculation ratio between reactors showed that the organic removal efficiency and the nitrification efficiency were more than 90% and 92%, respectively, and the denitrification efficiency was above 95% when C/N ratio was above 2.75. In these cases, the recycle ratio, the total hydraulic retention time and the recirculation ratio were found 30, 3hrs and 2 respectively, and the internal recycling in denitrification stage was needed only to fluidize the media well. The following experimental equation could be derived from distinguishing between the oxygen required for nitrification and the oxygen required for organic BOD oxidation. [grO₂/day] Total=1.5 [grBOD-5/day] + 4.95 [grNr/day] The relationship between the alkalinity and the recirculation ratio in nitrification, the feasibility of phosphorus removal using the principle of releasing phosphorus in the anaerobic reactor were also discussed briefly. |