Experimental Study On Nitrogen And Carbon Removal Performance Of Partial Nitrification Coupled With Anaerobic Ammonia Oxidation

Partial nitrosation coupled anaerobic ammonia oxidation is favored by most scholars as a new autotrophic denitrification process.Compared with traditional nitrification and denitrification,this process has the advantages of reducing aeration by50%,saving 100%of carbon source consumption and reducing sludge output.At present,this process has been successfully applied in the field of high temperature and high ammonia nitrogen wastewater,however,this process has rarely been reported in the treatment of urban low ammonia nitrogen domestic sewage.In order to provide theoretical reference and reference for the practical application of partial nitrification coupled anaerobic ammonia oxidation,this experiment optimized the working conditions of partial nitrification and anaerobic ammonia oxidation respectively,and finally explored the denitrification and carbon removal performance of partial nitrification coupled anaerobic ammonia oxidation.?1?Some research results of nitrosation?1?To explore the effect of anoxic/aerobic time ratio on the realization of stable partial nitrification.The time ratio of 30 min:60 min,45 min:45 min and 30 min:30min were used in the experiment.Under the three time ratios,NH₄⁺-N in the effluent was stable at 40th,37th and 22th cycles respectively.The concentration of NO₂^--N in the effluent increased to 26.07,19.82 and 23.45 mg/L respectively.The accumulation rate of NO₂^--N reached 98.94%,96.72%and 98.20%respectively.The three time ratios can achieve stable partial nitrification.In addition,simultaneous nitrification and denitrification appeared in all three time ratios.The aerobic time is longer,the more organic carbon source will be consumed.?2?To explore the effect of temperature on the realization of stable partial nitrification.The control temperature of the experiment is 12-15?,22-25?and 30-33?respectively.The NH₄⁺-N concentration of the effluent is 47.50,32.49 and 4respectively in the three temperature ranges after the operation is stable 12 mg/L,corresponding to NH₄⁺-N removal rate of 45.63%,61.60%and 95.35%respectively,and the effluent concentration of NO₂^--N is 13.95,48.34 and 59.96 mg/L respectively;the higher NO₂^--N accumulation can be achieved when the temperature is at 22-25?and 30-33?,and the NO₂^--N accumulation cannot be achieved when the AOB activity is severely inhibited at 12-15?.?2?Research results of anaerobic ammonia oxidation?1?To explore the effect of COD/NO₂^--N on the performance of anaerobic ammonia oxidation denitrification.The COD/NO₂^--N in the influent of anammox was1.5,2.0,2.5 and 3.0 respectively.When COD/NO₂^--N was 1.5,a large number of NO₂^--N is utilized by denitrifying bacteria,and the denitrification performance of the coupling system is poor.When COD/NO₂^--N was 2.5 and 3.0,the denitrification performance of the system is good;when COD/NO₂^--N was 2.0,the denitrification performance of the system is improved,and the NH₄⁺-N removal rate is increased to99.74%,and the best denitrification effect is achieved by anaerobic ammonia oxidation in the coupling system.?2?To explore the effect of inorganic carbon on the performance of anaerobic ammonia oxidation denitrification.The IC/NH₄⁺-N in the influent of anammox was 0-1,1-2,2-3 and 3-4,respectively.The results show that when IC/NH₄⁺-N is 0-2,IC/NH₄⁺-N has no significant effect on the denitrification performance of the system.With the increase of IC/NH₄⁺-N to 2-4,the total nitrogen removal rate increased with the increase of IC/NH₄⁺-N.Increasing IC/NH₄⁺-N can enhance anammox activity,so IC/NH₄⁺-N can be increased to improve the denitrification performance of anammox system.?3?Partial nitrification coupled anaerobic ammonia oxidation nitrogen and carbon removal performance research resultsAfter the partial nitrification and anammox processes are optimized to achieve stable operation,the denitrification and carbon removal performance of partial nitrification coupled anammox is explored.Under the best condition of partial nitrification?the time ratio of alternating anoxic/aerobic is 30min:30min,the temperature is 26??,the effect of aeration on the stable operation of partial nitrification was investigated.The SBR aeration capacity was set to 80,100 and 120L/h respectively.The results show that 100 L/h and 120 L/h of aeration are easy to achieve stable partial nitrification,and the NO₂^--N/NH₄⁺-N of effluent are 1.34 and 1.70,respectively,which can meet the ratio of influent substrate for anaerobic ammonia oxidation.Setting ASBR temperature was 26?and hydraulic retention time was 33H,the effects of different influent conditions on the performance of anaerobic ammonia oxidation denitrification and carbon removal were investigated.It was found that under influent conditions of NO₂^--N/NH₄⁺-N was 0.99 and COD/NO₂^--N was 4.1,the denitrification and carbon removal effect of anaerobic ammonia oxidation coupling system was the best.The effluent concentrations of NH₄⁺-N,NO₂^--N and NO₃^--N were2.91,0.51 and 4.43mg/L,respectively;the effluent concentration of COD was 28.22mg/L,meeting GB18918-2002 class a emission standard.