Pilot Experimental Research Of Fluidized-pellet-bed Bioreactor As A Decentralized Wastewater Treatment Technology

Fluidized-pellet-bed bioreactor (FPB) was an integrated wastewater treatmentsystem based on fluidized-pellet-beg technology, which combines activated sludgeprocess and the sludge and high-efficiency solid-liquid separation technology of watertreatment. In recent years, the technology developed by research project team, was anew sewage treatment technology, which set of coagulation, granulation,biodegradation, solid-liquid separation in one of the sewage treatment system. UnderFPB bioreactor in the early and application of the theory of adsorption regeneration, thisstudy proposed a new technology name as FPB bioreactor based on adsorptionregeneration.The mainly pollutant removal theories of the FPB are interception and adsorptionof the granular sludge layer and microbial metabolism to remove soluble organic matter,chemical phosphorus removal, simultaneous nitrification and denitrification to removeN. These theories can be showed by the different changes of the effluent indicators onthe start link. By controlling the hydraulic load、backflow、dosage、the dissolved oxygenconcentration in outer tube to create a good environment for the biotreatment, FPB canremove the soluble organic matter、 N、 P efficiently. During startup and themicroorganism domesticating, the time required to launch and domesticatemicroorganism of FPB is shorter than the conventional activated sludge process.6daysafter the startup, the effluent indicators of the FPB can reach the normal level. Inaddition, the FPB can operate continuously during the microorganism domesticating but the conventional activated sludge process can’t. Moreover, the FPB can start quicklyafter a period of breakup.By debugging the best operation condition has been made. When the hydraulicload is Q=5m3/h, the back flow is Q=2m3/h, the dosage is PAM=5mg/L,PAC=60mg/L,the amount of aeration is90m3/h, the stirring speed is6r/min, the FPB have the bestperformance on removing COD、TP、TN、 NH3-N、SS、turbidity. And the averageremoval efficiency is89.07%、87.77%、55.78%、72.08%、86.09%、95.75%. The itemscan meet the first grade A standards of Urban Sewage Disposal Plant ContaminationIntegrated Discharge Standard (GB18918-2002) except TN and NH3-N.The FPB canuse granular sludge formed by coagulation and granulation to create anoxicenvironment under aerobic conditions. And the system runs stably and overcome thepast problem like sludge up-floating and low efficiency of denitrification. Inside tube ofthe FPB can make the simultaneous nitrification and denitrification implementation oweto these factors. The content of N in the effluent can meet the first grade B standards ofUrban Sewage Disposal Plant Contamination Integrated Discharge Standard(GB18918-2002).