| The paper investigated the dynamical monitoring of OUR and PHB mainly based on the bench-scale urban sewage nitrogen and phosphorus removal treatment system (A/A/O process).The determination of the above two index was optimized. The coupling relationship between the profiles of OUR and PHB and A2/O system operation mechanism was established. Additionally, the variations of OUR and PHB with the operation of EGSB/A/O process was preliminarily discussed. This study laid the foundation for the construction of the forewarning system of urban sewage plants and was of great significance for scientific assessment, abnormal prediction and damage restoration of the sewage biological treatment system,which could provide some reerence for long-term operation of municipal wastewater treatment plant. Details are as following:In A2/O system, the influence of temperature on the PHB was limited. With temperature increasing from 17℃to 29℃,the content of PHB in the anaerobic pond increased and its content in activated sludge in the highest temperature increases about 4.8mg/gMLSS (about 19% of total) more than the one in the lowest temperature. This showed that the increase of temperature can promote the metabolism rate of PAOs, and thus promote the synthesis of PHB. However, when temperature exceeded 30℃,its content in the anaerobic pond decreased and can find the solution and flocculation of a large number of sludge. The operation of the system began to deteriorate.The content of PHB in anaerobic pool increased with the increase of F/M in system, and the synthesis' number of PHB increased with the increase of the amount of phosphorus releasing by anaerobic pool. And the change of this two tended to be coherent. It has close relationship between the amount of phosphorus releasing by anaerobic pool and the synthesis' number of PHB in micro-organisms. When the load decreased from 0.413 gBOD5/gMLSS·d to 0.176 gBOD5/gMLSS·d,the concentration of PHB in anaerobic pool reduced by 3.8 mg/gMLSS in average, rage fading about 16.7%. And this load's rate is basically able to offer the carbon to meet the needs of the micro-organisms to synthesize PHB. In the impact stage, PAO in the aeration tank are less active, which lose the function of storing PHB after oxygenating poly-phosphate in their bodies and thus greatly weaken their ability to absorb phosphorus excessively.In the restoration stage, the high F/M can promote the multiplication of PAO, and short SRT can make them more active, and improve their function of degradation. So the method of increasing the load or reducing SRT can help to accelerate the metabolism of PAO in the damage A2/O system.The normal value of OUR was between 7.1 mg(O2)/gMLSS·h to 13.3 mg(O2)/gMLSS·h, nitrification OUR was in the range of 0.88-2.95 mg(O2)/gMLSS·h. The temperature had clear effect on accelerating the activated sludge's OUR. When the efficient temperature for nitrification OUR ranged from 25℃to 33℃and the concentration of NO3--N ranged from 9.2 mg /L to 11.0mg/L, increasing F/M promoted OUR. Under the low C/N ratio, the removal of NH3-N in A2/O system had strong relationship with the oxygenation function of nitrobacteria and nitrosomas in the activated sludge. In the restoration stage, increasing the concentration of the sludge in aerator tank can promote the removal rate of NH3-N, and the method of decreasing SRT and increasing the restoration of F/M at the same time can accelerate the metabolism of nitrobacteria which effectively improve the system's function of nitration and nitrosation.In EAO system, the content of PHB in EGSB reactor was between 8.0mg and 9.5mg and the average value of removal rate of CODCr was 42.1%. And this two had the negative correlation. When the content of PHB in anaerobic pool was in the range of 8.3mg-9.7mg, the average removal rate of CODCr was 48.6%, OUR of nitrosation was between 1.5 mg(O2)/gMLSS·h to 3.1 mg(O2)/gMLSS·h,nitrification OUR was between 0.2 mg(O2)/gMLSS·h to 4.8 mg(O2)/gMLSS·h,and nitration OUR in EGSB was between 0.2 mg(O2)/gMLSS ? h to 4.5 mg(O2)/gMLSS·h,nitrosation OUR was between 0.18 mg(O2)/gMLSS·h to 9.6 mg(O2)/gMLSS·h, nitrosation OUR had extremely positive correlation with NO2--N and nitrosation OUR increases with the increase of NO2--N. PHB and OUR critical value in details: PHB formation in the anaerobic pool was between 12.5-27.8mg/L,nitrification OUR was between 0.8-1.85mg(O2)/gMLSS·h, nitrosation OUR was between 1.4-2.3mg(O2)/gMLSS·h ,meantime ,the system CODCr and NH3-N removal efficiency was best. By monitoring of PHB and OUR immediate values than the critical value, that is, the system can determine the CODCr and NH3-N removal rate is high or low, so can determine quickly whether system was in abnormal conditions,in order to timely and reasonable regulation and control of the system, play a direct role in forewarning, had a great application value and practical significance.
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