An Experimental Study On Cultivation Of Anammx Microoganisms And Its Control Condition

Anaerobic ammonium oxidation (ANAMMOX) has replaced the traditional nitrification and denitrification technology to play a great importance in microbiology and wastewater treatment with its unique advantages in resent years.However,the slow growth rate of ANAMMOX bacteria and its sensitivity to external environment make the practial utilization very difficult. In this paper,sequencing batch reactors were used to study the nitrogen load increasing based on the returns about ANAMMOX process under the temperature 37±1℃.Two manners (shorten the HRT and increase the concerntration of substrate) in increasing nitrogen load have been dicussed in the same experimental congditions.And analyse the the impact of high substrate-concerntration on ANAMMOX activity.Besides,investigate the translation ratio of NO2--N to NH4+-N by microorganisms gained from different sludges and different cultivation.Also the impact of NaHCO3 on the growth of microorganism and the pH of the system have been analysized.The main results were described as follows:1,The experiment of comparing two manners in increasing nitrogen load was performed in two SBRs,seeded with Anammox sludge enriched previously.Resuts can be gained via the removals of NH4+-N and NO2--N in two reactors that comparied with the shorten of the HRT,increasing the substrate concerntration is more prone to the increasing of nitrogen load.2,Based on the result 1 , increase the nitrogen load with high substrate concerntration.The reactors operated for 138ds,the maximum removals of NH4+-N and NO2--N achieve 100%,averaging 92.56% and 91.91% respectively.3,When the concentration of NH4+-N and NO2--N up to 405mg/L and 540 mg/L,the concentration of them in effluent increasedb,the activity of Anammox was inhibited. According to the curve of substrate concerntration to ANAMMOX activity,the inhibition came from NO2--N,which is reversible.4,By cultivating anaerobic sludge aerobicly,aerobic sludge aerobicly and aerobic sludge anaerobicly,the translation ratio of NO2--N to NH4+-N by microorganisms gained from the three were 1.327,1.306 and 1.22.The differernce existed amoung them is mainly because the cultivation manner and the inoculation were different.The translation ratio of NO2--N to NH4+-N by microorganism gained by cultivating aerobic sludge anaerobicly is more close to 1.32.5,According to the equation of ANAMMOX,microorganism metabolizes 1g NH 4+ for sythensization of cell needing 0.325g NaHCO3 extra high concentration of NaHCO3 has no impact on ANAMMOX minus the enough carbon for the growth of microorganism.Also calculate the relationgship of pH and the content of NaHCO3 in the solution,and at pH 8.0,the reaction rate of ANAMMOX is highest.