Investigation On Simultaneous Shortcut Nitrification And Denitrifying Phosphorus Removal Process By PHB

The biological nutrient removal technology was promoted in some extent with the problem of "eutrophication" growing critical, but the conventional nutrient removal technology issue is gradually exposed. While facing a low-carbon water sewage treatment and sustainable development requirements, the conventional nitrogen and phosphorus removal process has been unable to meet the requirements of wastewater treatment. In this research, study on shortcut denitrifying phosphorus removal in sequencing batch reactor under the condition of nitrification and denitrification and phosphorus removal process takes place in the same space and time, achieve the goal of "one carbon source for two uses", suitable for low carbon urban sewage treatment. Furthermore, shortcut denitrifying phosphorus removal also has the ability to solve the traditional nitrate removal phosphorus competition for carbon, sludge age, high energy consumption and so on.The text under low carbon sources of urban sewage is processed by artificial preparation, separate selection and enrichment nitrification bacteria and short denitrifying phosphate accumulating bacteria, then mix and coexisted them in a system. In order to improve the efficiency of phosphorus uptake under anaerobic phase, and the maximizing accumulation of PHB under low-carbon source, on this basis, this experiment proposed the mode of pre-aeration to promote accumulation of PHB. To explore nitrification and shortcut denitrifying phosphorus removal rate balance process favorable conditions, and achieve the purpose of effective steady degradation of PHB, we study the variation of TP, TN, NH4 +, NO2-, NO3- and PHB in shortcut SNDPR under different aeration mode(continuous aeration and intermittent aeration), and propose effective control condition.Tests showed: mix the domestication of nitrification bacteria and short denitrifying phosphate accumulating bacteria can achieve without additional dosing NO2- the shortcut nitrification and denitrification and phosphorus removal process, after its domestication TN removal rate was 83.1%, TP removal rate is 90.2%. Influent carbon concentration, the total release of phosphorus and the maximum concentration of PHB was positively correlated, and the impact on the accumulation of carbon concentration is greater than the impact of phosphorus concentration to the accumulation of PHB. When there was no pre-aeration of anaerobic PHB maximum accumulation, the way of pre- aeration can promote the maximize accumulation of PHB. The gas at 30L/s is conducive to the stability of shortcut SNDPR continues, its TN removal proportion was 93.7%, TP removal proportion was 96.4%; The low AF and f IA provides micro-oxygen environment for the system is conducive to shortcut SNDPR occurred and homogenized oxidation-reduction reaction, PHB degradation rate is more stable, get better nitrogen and phosphorus removal and save energy at the same time. Integrated from anaerobic and hypoxic phase nitrogen and phosphorus removal and PHB variation, the PHB can play a carbon source to result nitrification and denitrifying phosphorus removal process simultaneously, using the way of pre-aeration to maximize PHB accumulation at anaerobic phase, and result them degraded balanced and effectively in low oxygen phase, it can create favorable conditions for balance the nitrification and denitrifying phosphorus removal rate.