Research On Reaction Mechanism And Microbial Characteristic Of Biological Nitrogen And Phosphorus Removal Process

The nitrogen and phosphorus removal technology aimed for eutrophication control has been the focused study in the wastewater treatment area since 1980s. The study of biochemical mechanism and microbial characteristic is the basis of biological nitrogen and phosphorus removal process. To further analysis of biochemical mechanism of the reversed A~2/O process and the A~2/O process, the biochemical mechanism and microbial characteristic of the reversed A~2/O process and the A~2/O process were studied,The results showed that (1) the two processes had the similar capability in removal of ammonia-nitrogen and organic contamination under different different environment operating conditions, but the capability in phosphorus removal of the reversed A~2/O process was superior to that of the A~2/O process; when the temperature of wastewater was 6-15℃, the average removal efficiency of NH3-N and TP was 40.7% and 94.7%.(2) Through the determination of the SOUR of activated sludge, the anaerobic time didn't affect the microbial metabolic activity , the microbial metabolic activity of the reversed A~2/O process was better than the A~2/O process;there was difference between two processes;The zoogloea of A~2/O process was compact, while that of reversed A~2/O process was loose; there were lots of round-shaped and rod-shaped bacteria which were rich of compact grain, especially in round-shaped bacteria.(3) The metabolic profiles of the microbial communities in the activated sludge were monitored using Biolog microplates periodically during the experiment, the metabolic activities of the microorganisms in the system of reversed A~2/O process is better than in the system of A~2/O process; Among the 95 carbon sources in Biolog microplate, carboxylic acids, amino acids and carbohydrate were much easier to be utilized by the microorganisms in the activated sludge system of both A~2/O process and reversed A~2/O process than the other carbon sources.Under the current conditions, the variation of the metabolic profiles in both processes showed little difference.