| Abstrakt: |
In order to solve the problems of difficult selection of carbon sources and high cost of dosage in advanced treatment of wastewater treatment plant, denitrification biological filter was used to explore the denitrification performance of different carbon sources. In this study, the denitrification performance of three carbon sources (sodium acetate, ethanol and methanol) at different hydraulic retention time (HRT), nitrogen ratio (C/N) and influent NH4+-N concentration and the microbial community structure at different heights of the reactor were investigated. The results showed that under the condition of low carbon nitrogen ratio, as the HRT increased, the removal efficiency of NH4+-N and NO3--N in the effluent of three systems with sodium acetate ethanol and methanol as carbon sources gradually increased, and the accumulation of NO2--N in methanol system was the lowest in the three systems. With the gradual increase of carbon to C/N, the concentration of NH4+-N and NO3--N in the three systems gradually decreased. The effluent TN concentration of sodium acetate and methanol system was less than 1.5 mg/L when C/N was 6 and 5, which met the Class W of Environmental Quality Standard for Surface Water. With the increase of influent NH4+-N concentration, it led to the increase of NO2--N accumulation degree, resulting in the increase of effluent TN concentration. Carbon sources led to significant differences in the abundance of the three systems at the phylum level. The differences at the genus level were more obvious, and the total relative abundance of denitrifying bacteria was in the order of sodium acetate system > ethanol system > methanol system. The results of this study can provide a theoretical reference for the selection of carbon source and the use of dosage in waste-water treatment plants. [ABSTRACT FROM AUTHOR] |
