Study On The Phosphorus Removal Effect And Influential Factors In The SUFR

With the aggravating of water entrophication pollution, the design of municipal wastewater treatment process must consider not only nitrogen removal, but also phosphorus removal especially. Spiral Up-Flow Reactor (SUFR) is developed which is a new facility, energy saving, high efficiency of biological nitrogen and biological phosphorus removal system. It always kept high efficient removal effect on phosphorus and nitrogen in some years, phosphorus removal especially. So the SUFR biological phosphorus removal system is studied in this dissertation. The effect of the character of DO,C/N and sludge age on phosphorus removal in SUFR system. At the same time the phosphorus removal effect of phosphorus-accumulating bacteria was investigated .The followings were studied :①the effect of DO on the phosphorus removal②the effect of influent COD/TN on the phosphorus removal③the effect of SRT on the phosphorus removal④the charcater of phosphorus-accumulating bacteria⑤kinetic model of the biological biological phosphorus removal process.The results showed that①DO of aerobic zone changed among 1.5～3.5mg/L, the removal efficiency of phosphorus was not change greatly in the system. The average removal rate of TP was kept over 94%. The effluent concentration of TP was less than 0.5mg/L. The correlation coefficient between TP and DO was 0.075.②when the influent COD/TN ratio among 7~10, the removal efficiency of phosphorus increased as C/N increasing. The system had good removal efficiency of phosphorus generally. The removal efficiency of phosphorus was more than 88%. The effluent concentration of TP was less than 1.0mg/L.③when the sludge age were 15d ,20d ,25 d separately, the system always had good removal efficiency of phosphorus. The removal efficiency of phosphorus was more than 90%. The effluent concentration of TP was less than 0.5mg/L. The removal efficiency of phosphorus was the best when the sludge age was 20d.④There was some phosphorus-accumulating bacteria which had good removal efficiency of phosphorus. One of these was Bacillus subtilis probably. The removal efficiency of phosphorus was 49.33%.