| The living surrounding of human is polluted by nitrogen compounds, of which ammonia is the chief pollutant and has attracted a lot of attention. Anaerobic ammonia oxidation (Anammox) is a novel promising biological nitrogen removal process. In order to put it into practical use, Anammox inocula must be achieved, the bacterial growth must be promoted and the biomass must be hold.Based on similarity of Anammox to denitrification, the denitrifying bacteria was used as inoculum of Anammox reactor, the denitrifying condition was used to promote the bacterial growth, the denitrifying biofilm was used to hold the biomass. During start-up of Anammox reactor, the denitrifying biofilm was firstly cultivated and was then transited from denitrification to Anammox. Anammox biofilm reactor was successfully started up and operated with synthetic wastewater and sludge dewatering effluent, respectively. The main results were as follows:1) Anammox reactor was successfully started up with heterotrophic denitrifying biofilm. The widespread heterotrophic denitrifiers grow faster than Anammox bacteria. Based on substrate diversity and metabolic diversity, the heterotrophic denitrifying biofilm was firstly cultivated and was then utilized as inoculum to start up Anammox reactor. When treating synthetic ammonium-containing wastewater, the reactor Rl was successfully transited from denitrfification to Anammox within 100 days, volumetric total nitrogen (TN) loading rate was up to 143.34 mg/L-d with ammonia removal percent of 99.09% and nitrite removal percent of 99.06%, respectively. When treating sludge dewatering effluent with reactor R3, the transition could be achieved successfully within 85 days, the effluent ammonium and nitrite was both less than 1 mg N/L with removal percent of 99.67% and 99.88%, respectively.2) Anammox reactor was also successfully started up with autotrophicdenitrifying biofilm. Based on substrate diversity and metabolic diversity, the autotrophic denitrifying biofilm was firstly cultivated and was then transited from denitrifcation to Anammox. The start-up of reactor R2 was accomplished within 110 days when synthetic ammonium-containing wastewater was used as influent, volumetric loading rate was up to 144.63 mg TN/L-d with removal percent of 98.59% for ammonia and 99.08% for nitrite, respectively.3) The results showed that the performance of Anammox biofilm reactor Rl was better than that of reactor R2. Because of more biomass in reactor Rl than that in reactor R2, reactor Rl could achieve higher loading rate. The tolerance of reactor Rl to influent concentrations of ammonia and nitrite was stronger and nitrogen removal efficiency of reactor Rl was higher than that of reactor R2. HRT of reactor Rl was shorter than that of reactor R2 at the same influent concentrations.4) The nitrogen removal efficiency of the Anammox biofilm reactors was tested. With the optimum influent concentration (385.43 mg NH4+-N/L and 420 mg NOz'-N/L) of synthetic wastewater and at HRT of 24 h, the maximum volumetric removal rate of reactor Rl was up to 658.14 mg TN/L-d. With influent (both ammonia and nitrite) concentration of 140-160 mg N/L and at HRT of 12 h, effluent ammonia of reactor Rl could meet the national discharge standard I and the volumetric removal rate was 528.8 mg TN/L-d. As to reactor R2, the maximum volumetric removal rate was up to 620.09 mg TN/L-d when operated with the optimum influent concentration (350.89 mg NH4+-N/L and 388.25 mg NO2--N/L) of synthetic wastewater and at HRT of 24 h, effluent ammonia could also meet the standard I with volumetric removal rate of 500.64 mg TN/L-d when operated with influent concentration (both ammonia and nitrite) of 140-160 mg N/L and at HRT of 12 h. While treating sludge dewatering effluent containing 245 mg NH4+-N/L with reactor R3, the maximum volumetric removal rate was up to 584.99 mg TN/L-d at HRT of 17 h, effluent ammonia could meet the national standard II and standard I at HRT of 28 h and 36 h, respectively, e...
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