Study On The Effect Of Lower Temperature And Longer Sludge Age On Municipal Wastewater In SUFR System

The spiral up-flow reactor(SUFR) is a new stand pattern reaction technique of waste water treatment which has a mechanical leading flow system. The characteristic of spiral up-flow was favorable to enhance gradient distributing of the substrate, prolong the retention time of the substrate in the reactor, and made the SUFR be similar to plug-flow reactor and could increase the capacity utilization of the reactor. According to the characteristic of SUFR system, the operating result of temperature between 8℃ and 20℃ on biological nutrient removal was analysed on the base of reviewing the theory and technology on N and P removal. And the peculiarities of the SUFR system with the longer sludge age were analysed through test comparison .The followings were studied: 1) Studying on the effect of low temperature on nitrigen and phorsphours removal; 2)kinetic model of the biological nitrogen removal and biological phosphorus removal process coupled with the different temperature; 3) Studying on the effect of low temperature on the character of active sludge in the SUFR system; 4) Studying on the effect of longer sludge age on nitrigen and phorsphours removal; 5) Studying on the effect of longer sludge age on the character of active sludge in the SUFR system.According to the above study result, The operating result of temperature between 8℃ and 20℃ on biological nutrient removal in SUFR system indicated that the effluent COD was less than 40 mg/L and the effluent TN was less than 10 mg/L, although the decrease of removal of COD and TN coupled with low temperature was observed. The drop in temperature had no significant impact on phosphors removal. Low temperature did harm to the characteristics of the sludge and caused sludge to bulk. The sludge relying on the characteristic of Spiral up-flow reactor system,however ,was activated and resumed rapidly. The effluent quality of SUFR system with the longer sludge age was up to with the first class of discharge standard of pollutants for municipal wastewater treatment plant (GB8978-1996). The higher efficiency of TN removal in the SUFR system(θc=32d) was observed. The removal of TP in the SUFR system(θc=32d) was less than 0.5 mg/L, although the decrease of removal of TP coupled with longer sludge age was observed. The SVI of the SUFR system(θc=32d)was less than 135. And SOUR of the sludge in the aerobic zone of SUFR system(θc=32d)was in the range of 10~18 mgDO/(gVSS·h) , which was lower than that in the SUFR system(θc=20d). The microbe ecology of the SUFR system(θc=32d)was abundance. The foodchain in the SUFR system(θc=32d)was more full.The study of this dissertation belongs to the scientific research (2001BA604A01) of Tenth Five-Year plan in china. This research acquired the values of important parameters that could be used in actual design and control, provided support for the engineering utilization of the SUFR in municipal wastewater treatment.