Research On The Performance Of A New Suspended Filler Bioillm Reactor

In this subject， a new suspended carrier biofilm reactor was developed based ontraditional biofilter， and the suspended carrier in the reactor are in circulating fluidized stateto improve the performance of the reactor. The experimental results show the new suspendedfiller biofilm can be integrated to remove nitrogen and carbon，and it also has certain amountof phosphorus removal capabilities.This study has examined the performance of the new biofilm reactor with simulatedwastewater.First， the study examined COD removal efficiency and the biomass change on thecarrier during the biofilm formation experiment which took up nearly two months. The resultsshow that the COD removal efficiency reached80%three weeks after the initiation of theexperiment; the biomass on the carrier peaked7.27kg/m³after55days.Second, the study examined the removal efficiency of NH4+-N，TN，TP，COD by newbiofilm reactor. The impacts of DO, HRT, C/N, carbon sources on reactor’s performance werealso investigated. The results show that the reactor has steady COD removal efficiency withan average removal rate of80%; the maximum removal rates of NH4+-N and TN were97.7%and52.5%, the average removal rate of TP was36.2%. DO has a great impact on the removalefficiency of TN, the optimum DO for TN removal is3.9mg/L, DO has a less impact on theremoval efficiency of PO43--P; HRT has a greater impact on the removal of NH4+-N, while hasa less impact on on the removal of TN and COD; C/N has a great impact on the removal ofNH4+-N、TN�'�PO43--P, the removal efficiency increases as the C/N increases; the removalefficiency of NH4+-N、TN and PO43--P has very little change when the carbon source changesfrom sodium acetate to glucose, but there will be a1to2weeks adaptation phase, and carbonsources have slight Impact on effluent SS. The study has also examined the impact of DO andHRT on nitrite accumulation in the reactor, NO₂^-N accumulation rate reached12.2%at theDO=3.9mg/L, HRT=6.8h.Finally, the study compared the characteristics of the carrier-biofilm and traditionalactivated sludge. The results show that the sludge concentration on the carrier is3times of theactivated sludge, and the nitrification intensity per unit volume is1.24times of the activatedsludge; the NO₃^--N reduction rate is2.36mg/（g.h） and NO₂^--N reduction rate is1.45mg/（g.h）;the proportion of live bacteria on the carrier decreased from74.8%to48.8%after runningabout one year, less than that of activated sludge which is61.1%.