Study On Treatment Of Organic Wastewater In Fluidized Bed By A Biofilm Sequencing Batch Reactor (BSBR)

In this paper the author briefly introduces the development of Sequencing Batch Reactor (SBR) technology, the principle of its work, features and the latest improvement.The Biofilm Sequencing Batch Reactor (BSBR) process, which using porous polymer particles as carriers, is studied on the treatment of synthetic organic wastewater in a three-phase fluidized bed (TFB). Filling duration of 1 minute, reacting of 3 hours, settling of 3 hours, draining of 5 minutes and idling of 1 hour are characterized in a tranditionl SBR. The whole period is about 7.0 hours. The removal rates of CODCr and NH4+-N exceed 90% and 70% corresponding to the airflow rate of 60 L/h, the concentration of treatment of 800-1400 mg/L and the volumetric organic loading rate (VOLR) of 1.22-2.13 KgCOD/m3·d. Filling duration of 1 minute, reacting of 3 hours, settling of 1 hour, draining of 5 minutes and idling of half an hour are characterized as the optimum operation running parameters in the BSBR. The whole period is about 4.5 hours. The removal rates of CODCr and NH4+-N exceed 90% and 70% corresponding to the airflow rate of 40 L/h, the concentration of treatment of 600-1400 mg/L and the volumetric organic loading rate (VOLR) of 1.78-4.15 KgCOD/m3·d. Though the removal rates of the two processes are basically identical, the BSBR has some advantages. For example, the airflow rate of BSBR is lower, the range of treatment concentration is wider, the running period is shorter and VOLR is higher and so on.The study of appropriate removal concentration ranges of CODCr and NH4+-N during the BSBR process shows that, the range of CODCr is from 600 mg/L to 1 400 mg/L, the removal rate of CODCr exceeds 90% and the concentration of CODCr in effluent is below 100 mg/L; the range of NH4+-N is below120 mg/L, the removal rate of NH4+-N exceeds 70%, the concentration of NH4+-N in effluent is below 20 mg/L. The results demonstrate that the BSBR process has superior stability in effluent and high removal potentiality of NH4+-N. When this process is used to treat high concentration organic wastewater under the condition of the experiments, the airflow rate of 60 L/h is appropriate.The settling and adsorption character of sludge, the optimum CODCr/NH4+-N value, and characters of resisting-change of VOLR and pH are also studied in this paper. The all results show that the BSBR process is superior to the SBR process.