YIN Hang, HE Li, LU Jiancong, et al. Effect of hydraulic retention time on nitrogen and phosphorus removal by biofilm and granular coupling process[J]. CIESC Journal, 2014, (6): 2294-2300.
YIN Hang, HE Li, LU Jiancong, et al. Effect of hydraulic retention time on nitrogen and phosphorus removal by biofilm and granular coupling process[J]. CIESC Journal, 2014, (6): 2294-2300.DOI: 10.3969/j.issn.0438-1157.2014.06.046.
In home-designed coupling unit consisting of suspended carrier biofilm and granular sludge
biofilm supported nitrifying bacteria and denitrifying phosphorus granular sludge were used for investigating the effect of the hydraulic retention time (HRT) on nitrogen and phosphorus removal to arrive at optimizing process parameters. In the experiment
HRT was set at 6 h
7 h
8.5 h and 10.5 h. The results showed that when HRT was 8.5 h
the removal rates of COD
ammonia nitrogen and total nitrogen were 91.26%
80.68% and 70.58% respectively. The release rate of phosphorus was 0.47 mg P·(g SS)-1·h-1
anaerobic phosphorus release and carbon source utilization were both at the highest rate
PO43--P removal rate 76.50%
denitrifying phosphorus removal efficiency 1.04 mg P·(mg NO3--N)-1. At the hydraulic retention time 8.5 h
the system had higher nitrogen and phosphorus removal efficiency. When the HRT was too short
nitrogen and phosphorus removal was incomplete
If too long
the system was unstable. Therefore
the system's optimal hydraulic retention time was 8.5 h.