Influence of influent C/N on sludge granulation process and nutrient removal pattern

In this paper, firstly, the relevant parameters of influent C/N quantification were selected, and then, on the basis of the relevant parameters, the apparent shear force formula was deduced, and the apparent shear force was used to reflect the hydraulic condition of the reactor. Next, the experimental device, operation method, influent water quality and analysis method were determined, and the influences of influent C/N on the sludge granulation process were derived from the influences of group I C/N ratio on anaerobic granular sludge and group II C/N ratio on anaerobic granular sludge. Then, the return sludge from the Guangzhou sewage treatment plant in Guangdong Province was selected as the experimental seed sludge, and the methanol concentration of 0.13g/L (COD=200mg/L) was used as the experimental water quality, and the influences of influent C/N on nutrient N₂O denitrification were illustrated by the experimental analyses. The results showed that the NO₂⁻ − N accumulation rate was maintained above 81% in all five water intake modes, and when the ratio of water intake (1:1) and (2:1), a higher concentration of NO₂⁻ − N was accumulated in the first nitrification stage of 26.5 mg/L and 24.9 mg/L, respectively, which could give full play to the advantages of nitrifying bacteria to achieve nitrification rapidly and also reduce the production of nutrient salt N₂O. This study combines macro-experiment and micro-analysis to provide a theoretical basis for granular sludge technology.