Isolation of heterotrophic nitrification bacteria and nitrifying character of membrane bioreactor

The heterotrophic nitrification bacteria existed in MBR system possessing SND effect of 80% was isolated and cultured; and its mortifying characteristic was studied. 3 bacteria strains isolated adopting new type heterotrophic nitrification bacteria isolating screening technique of combining the traditional microbiological method with the modern molecular biological means could utilize fully organic carbon for oxygen breath, possessed properties of heterotrophic organism and also the nitrification function of producing NOx-. After did 21 days culture the removal rates of COD by three strains B1, B2, B3 were 52.58%, 71.72%, and 77.74%, respectively; and the removal rates of total nitrogen were 35.6%, 61.2% and 68.7%, respectively.