| On the basis of single factor experiment, the denitrification unit of a combined sewage plant in Xinjiang was optimized by Box Behnken response surface method. The results showed that the effect on denitrification performance from strong to weak was carbon nitrogen ratio (C/N), organic load (F/M) 〖JP2〗and internal reflux ratio(R). The optimum working conditions after model optimization were C/N=7.45, R=52.61%, F/M=〖JP〗0.10 d-1, the verification tests were conducted under these working conditions in the sewage plant, the average removal rates of NH3 N and TN were 87.23% and 91.20%, respectively. The average values of NH3 N and TN in effluent were 0.37 mg/L and 6.09 mg/L, respectively, all met classⅠA standard. The relative error between the removal rates and the predicted values of NH3 N and TN were 0.38% and 0.55%, respectively, which were close to the predicted values of the model. |
