ANAMMOX Start And COD Its Impact

Anaerobic ammonia oxidation technology compare to traditional nitrification denitrification technology, do not need to provide organic compounds as electron donor,so it save the cost. At the same time, to prevent the generation of two pollution, anaerobic ammonia oxidation because ammonia nitrogen and nitrite nitrogen direct response, energy saving, but also save the neutralizer etc., so the anaerobic ammonia oxidation process and technology has high research value.Inoculated with nitrifying sludge, the anaerobic ammonium oxidation was started up successfully for120d in an anaerobic sequencing batch reactor. The experimental conditions were as follows:temperature (35±1)℃,HRT24h and pH7.3-8.5. Experimental results indicated that when the average volumetric load of total nitrogen was0.23kg/(m3·d),the average removal rates of NH4+-N, NO2--N and TN were97.54%,97.49%and84.31%at stable stage. The ratio of ammonium removal, nitrite removal and nitrate increase was1:63:0.23at start-up stage, and it was1:1.27:0.25at stable stage. The pH increment between influent and effluent changed from0.85at start-up stage to0.24at stable stage. Denitrification and ANAMMOX were existed simultaneously at start-upstage, however, ANAMMOX became the dominant reaction at stable stage. MLSS and MLVSS/MLSS decreased at the beginning and then increased. The changing process reflected the decease of nitrobacteria, denitrifying bacteria and the enrichment of ANAMMOX bacteria. This was in concert with nitrogen removal performance.The influence of organic matter on anaerobic ammonium oxidation, at COD0,50,150,200,250,300,350,400,450,500mg/L, the removal rate of reactor NH4+-N, NO2--N, NO3--N, TN, COD changes. The experimental results show that the COD<150mg/L, with the COD concentration increasing, anaerobic ammonia oxidation were not inhibited, but be certain to promote. With the increase of the concentration of COD, COD>200mg/L, anaerobic ammonia oxidation is inhibited.Effect of C/NH4+-N on anaerobic ammonium oxidation. When C/NH4+-N at0,0.63,1.24,1.79,2.4,3.07,3.81,4.59,5.7,the continuous measurement of NH4+-N in the reactor, can be seen in the C/(NH4+-N) at0,0.63,1.24,1.79, ammonia nitrogen removal basically end there was no significant difference between the removal of ammonia nitrogen, along with the time of removal are relatively good,when C/(NH4+-N) is1.79, the best Hydraulic Retention Time is50h. In the C/(NH4+-N) was 2.4,3.07,3.81,4.59, ammonia nitrogen removal significantly reduced, suggesting a role for anaerobic ammonia oxidation is inhibited, to20h in the experiment, the reduction ratio in each stage of ammonia nitrogen removal rate are reduced.