Application Studies On Treatment Of Nitrogenous Water With Heterotrophic Nitrification Bacteria

With the development of industrial and agricultural production and the improvement of living standards,the discharge of nitrogen compounds increased dramatically,so it has become the main pollution sources of the environment.Also it caused public concerning.Ammonia nitrogen is the main form in the water,which made the eutrophication and the environment pollution,it also will destruct the ecological environment which we depend on.Because of the different requirement of the different nitrifiers and denitrifiers for nourishment and DO,the process of removal of nitrogen is very complex and the application is limited. Recently,some new typical bacteria by which nitrogen can be effectively removed have been found. This provides a new method for developing the application of the biological removal of nitrogen. In this experiment,we did some basic research on thehetertrophic nitrification bacteria and then made the hehetertrophic nitrification bacteria applied in SBR reactor.6 strains of heterotrophic nitrification bacteria screened from the lab was studied in the ammoxidation medium.Through the 12 days'culturing the COD removal rate could reach to over 45%,TN and NH4-N removal rate could reach over 60%.We made the hehetertrophic nitrification bacteria applied in SBR reactor.As the reactor run into stable stage,removal rate of ammonia nitrogen reach to 82.96%.The ecological factors affecting the nitrification efficiency of heterotrophic nitrifying bacteria were discussed.The results showed that the best temperature for heterotrophic nitrobacteria reacting in the SBR reactor was 29℃,the removal rate of the ammonia-nitrogen and TN are 82.28%and 47.27%,so with the higher of the temperature the heavier of the removal rate.The pH also has the more effect on the removal rate.As the pH is 8.0 the removal rate of ammonia-nitrogen is 80.15%,As the C/N rate is less than 4.5,the removal rate of the ammonia-nitrogen and the TN increased.As the C/N rate is 6,the removal rate of the ammonia-nitrogen is 73.37.As the C/N rate is 9,the removal rate of the total nitrogen reached to 52.84.The PCR-DGGE profiles showed that the YS1,YS2 and YS6 were the dominant bacterium in SBR reactor.Made three strains of heterotrophic nitrification bacteria which had well effect of nitrifacation and aerobic denitrtrification bacteria from the lab into amplification culture,and estbilished the SBR reactor and the suspended biological stuffing SBR reactor to realize the simultaneous nitrification and denitrification.As the stable stage in the SBR reactor,the removal rate of TN reach to 43.43%,the removal rate of COD reach to 73.12%.As the stable stage in suspended biological stuffing SBR reactor,he removal rate of TN reach to 79.03%,the removal rate of COD reach to 87.18%.The result showed that the suspended biological stuffing SBR reactor was batter than the SBR reactor.The result provide thoretical basis for the applicationg of heterotrophic nitrification bacteria in other membrane bioreactor and provide thoretical basis for simultaneous nitrification and denitrification in practical application.