Study On Biological Nitrogen And Biological Phosphorus Removal And Sludge Characteristic In Spiral Up-Flow Reactor System

With the aggravating of water entrophication pollution, the design of municipal wastewater treatment process must consider not only phosphorus removal, but also nitrogen removal. But as far as the level of the technology, economy, management and limited ground in china is concerned, a energy saving and high efficiency of biological nitrogen and biological phosphorus removal system is eagered to developed. Spiral Up-Flow Reactor (SUFR) is developed which is a new facility, energy saving, high efficiency of biological nitrogen and biological phosphorus removal system. So the SUFR biological nitrogen removal and biological phosphorus removal system is studied in this dissertation. Its aim is to attain a better result. What's more, the effect of the character of active sludge is studied to know of SUFR system.The followings were studied over one year: 1) On the condition of the assumed SRT and F/M , making SUFR system remain in a steady state to attain a good effect;2)Changing SRT, ratio of influeal, aerobic time, ratio of refurned sludge and sludge loads to know of effect of the biological nitrogen removal and biological phosphorus removal, in the result, founding a best result;3)Studying the character of active sludge in the SUFR system;4)Studying the character of grain sludge in the SUFR system;5)Studying subminiature creature and its effect in the SUFR system;6)kinetic model of the biological nitrogen removal and biological phosphorus removal process.According to the above study result, it can be proved that on the condition of continuous stable operation of the system process, Results of the tests on the removal of COD, nitrogen and phosphorus using spiral up-flow reactor (SUFR) system over one year showed that the effluent concentration of COD, total nitrogen (TN) and total phosphorus (TP) was below 31mg/L, 10mg/L and 0.5mg/L respectively, and the removal efficiency of COD, TN and TP was kept over 94%, 86% and 96% respectively. Owing to special structure of SUFR biological nitrogen removal and biological phosphorus removal system and current character, active sludge easily growed grain sludge, as a result, attaining a good effect of sedimentation, SVI is from 25 to 45, under the SVI of the municipal wastewater. Due to a good effect of grain sludge, SUFR system has a function of nitration, denitrifying and denitrifying phosphorus. All kinds of creature in this SUFR system shape steady animalcule communities, its not only improved systemic capacity of resisting sludge burthen, but also ensured effect of biological nitrogen removal and biological phosphorus removal, making the effluent quality of SUFR system is up to with the first class of discharge standard of pollutants for municipal wastewater treatment plant (GB8978-1996).The study of this dissertation belongs to the scientific research (2001BA604A01) of Tenth Five-Year plan in china. The results of research have showed great prospect in treated water quality improvement, have laid the foundation for advanced study of metabolism of the biological denitrifying dephosphatation in china. The research is important both in application and theory.