| Circle push-flow reactor process has been formed as a modification of OCO process through test research. As a advanced technology, it has the functions of phosphorus removal and denitrification with facilitation,effectiveness and economic. This technology has already been approved as Invention Patent (200710092501.7) and Utility Model Patent (ZL2005 2 0010545.7). According to the characteristic of the system, the dissertation carried out test and analysis on the effect of the factors ofOn the basis of prophase research, the followings were studied.①The thesis investigated the effects of feed water COD, HRT,SRT,the association of DO and C/N on biological nitrogen and phosphorus removal in the Spiral Up-Flow Reactor system. Furthermore, the experiment was to optimize the operating conditions by analyzing on the characteristics of reactors.②With the comparison of the typical loop reactor—oxidation ditch,in order to optimize the operating conditions by analyzing on the characteristics of reactors.③The kinetics model of biological nitrogen removal in the system is established, simulated and analyzed.According to the study above, the conclusions are as follows. The results show that all the factors above have a greater impact on biological nitrogen and phosphorus removal.The feed water COD concentration, that varied from 100～200 mg/L,200～300 mg/L,300～500 mg/L1and more than 600 mg/L, has no obvious effect on the remove of COD, and the removal efficiency is above 90%. When the feed water COD is from 200 to 500 mg/L,the removal efficiency of TN,ammonia nitrogen and TP is stable, and the removal efficiency is respectively above 70%,95%and 80%.When the feed water COD concentration is too low(100～200 mg/L),the removal efficiency of nitrogen and phosphorus is worse because of the lack of carbon recourse. When the feed water COD concentration is too high (above 600 mg/L), the removal efficiency of nitrogen and phosphorus is also worse because of the change of the microbial populations. In addition, with the rising of the feed water COD concentration, the concentration of each water index of the system is also rising.To balance the demand of nitrogen removal and phosphorus removal and the Operating costs,the HRT should be 10 hours. In the condition, the removal efficiency of TN,ammonia nitrogen and TP is respectively 95.42%,71.59%,96.99% and 83.25%,and the effluent quality reaches the first grade standard. In addition, the release phosphorus mass and the absorption rate of phosphorus are respectively 17.83 mg/L and 8.95 mg/ (g/h).When the SRT is between 15 and 20 days, the removal efficiency of nitrogen and phosphorus is very well. The removal efficiency of COD,TN,ammonia nitrogen,TP and phosphate is respectively above 94%,74%,94%,84%,83%. In addition, the phosphorus rate of sludge is between 4.5～4.8%.The association of DO concentration and C/N is not significant on the removal of COD. No matter what DO and C/N is, the remove effect of COD is very well. This may relevant with the special circulation structure cycle of the system.The Circle push-flow system can form good flow, and the concentration of matrix can be gradient distributed. This is better for the contact of matrix and microbial. The association of DO concentration and C/N is significant on the removal of nitrogen removal and phosphorus removal. The optimal C/N is 7～18,and the optimal DO concentration is 1.5～1.8 mg/L. In this condition, the removal effects of nitrogen and phosphorus are the best, and the removal efficiency of nitrogen and phosphorus is respectively75% and 80%.By contrast, the Circle push-flow process is a process of circulation which has better remove effects of nitrogen and phosphorus.The kinetic equations of anoxic denitrification and aerobic nitrification are derived through the establishment of material balance equations in the system. And the kinetic parameters are obtained. Meanwhile, the kinetics model of biological nitrogen removal in the system is established on the foundation. The results show that the derived kinetic models have strong ability on fitting data to forecast the process of biological nitrogen removal in the system.The research acquired the important parameters that could be used in practical design and operational control, and it provided technical support for the engineering application of the Circle push-flow system. |
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