Analyses of Nitrogen Metabolism and Functional Microbial Community in Aerobic Tanks of Hydrolysis Acidification and Multistage Aerobic Process for Tannery Wastewater

Abstract

The actual tannery wastewater was treated by hydrolysisacidification and multistage aerobic process (A/O3). The growthstatus of microorganisms in three aerobic tanks was measuredwith the Biolog microplate method to reflect the ability ofmetabolizing nitrogen source. In the three aerobic tanks, thefunctional differences between different nitrogen sourcemetabolism microbial communities in three aerobic tanks werecompared and analyzed. The results of the present study haveshown that when the concentrations of ammonium chloride andpotassium nitrate were low, the metabolic activity of nitrifyingbacteria was higher than that of denitrifying bacteria in aerobictanks. With the increase of concentration of ammonium chlorideand potassium nitrate, the metabolic activity of denitrifyingbacteria was gradually increased, and gradually higher than thatof the nitrifying bacteria metabolism. When the concentrationsof ammonium chloride and potassium nitrate were 100 mg/Land 20 mg/L, and the concentrations of ammonium chlorideand potassium nitrate were 150 mg/L and 30 mg/L, O1 has thebest denitrification effect. However, when the concentrations ofammonium chloride and potassium nitrate were increased,nitrogen load was increased, the denitrification effects ofnitrification and denitrifying microorganisms were fluctuated.And the diversity index analyses by five indexes showed that themetabolic capacity of microorganisms to carbon sources is good.