关键词: A²O工艺, 反硝化除磷, 过量曝气, 脱氮除磷

Abstract: A pilot-scale nutrient removal activated sludge system, based on the A²O configuration, was used to treat brewery wastewater.In the experiment, the existence of denitrifying phosphorus removing bacteria (DPB) and the contribution of DPB to phosphorus removal was observed.The tests showed the average total amount of anoxic P uptake accounted for 70% of the total amount of P uptake of the system at steady state, oxygen requirement could be decreased significantly(about 25%).Denitrifying phosphate removal resolved the competition for organic substrates between Poly-P organisms and denitrifiers under lower organic loading.Effluent total-P concentration could achieve less than 0.30 mg•L^-1 and average effluent total-N was less than 10 mg•L^-1.It is clearly demonstrated that the phosphorus uptake almost stopped in an over-aerated system, the released phosphorus could not be taken up fully again.Consequently, incomplete phosphorus uptake led to temporary reduction of biological phosphorous removal efficiency.It took about the time of one sludge age to eliminate that disturbance.

Key words: A²O工艺, 反硝化除磷, 过量曝气, 脱氮除磷