Effects of SRT on N2O production during nitrification and denitrification
SRT对于污水脱氮过程中N2O产生的影响

We investigated the production and conversion rate of N2O during nitrification and denitrification under different sludge retention times (SRT): 9 d and 15 d. The results showed that nitrification was the main source of N2O. The N2O production with SRT 9 d was 1.2 times higher than that with SRT 15 d.The production and conversion rate of N2O during nitrification and denitrification under different SRT conditions were also investigated. The results turned out that the N2O production was 4.62 mg·L-1 with SRT 9 d and 3.8 mg·L-1 with SRT 15d. The conversion rate was 11.2% with SRT 9d and 7.8% with SRT 15d. The long time domesticated short SRT system can perform a good nitrogen removal rate, under the two SRT conditions, the nitrogen removal rates were all above 96%. Consequently, in order to reduce N2O production, it is necessary to keep a long SRT to avoid increasing the N2O production and conversion rate.