Study on Backwashing of Two- Phase Biological Aerated Filter

摘要

400000 ton per day wastewater treatment plant which adopts biological aerated filter process was taken as research site, to seek out the rules of backwashing. The results indicates that when water backwashing rate is 4.2 L/(m2·s) and air backwashing rate is 22 L/(m2·s), the curves of two phases aerated biological filer with uniform media are similar which consist of the flat, the culmination and the drop. However, Difference does exist between the curves of the two-phase biological aerated filter. The culmination of the C removal filter (phaseⅠ) is at the beginning of the air water washing, while the culmination of the N removal filter (phaseⅡ) is at the end of the air water washing