ZHANG Yun-bei,MA Min,GONG Ling,et al.Simulation of Denitrification of A/A/O Process and Its Optimization[J].China Water & Wastewater,2022,38(2022 1 1):88-94.
Simulation of Denitrification of A/A/O Process and Its Optimization
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第38卷
Number:
2022 1 1
Page:
88-94
Column:
Date of publication:
2022-01-01
- Abstract:
- To solve unstable denitrification caused by high total nitrogen and low BOD5/TN ratio in influent of a wastewater treatment plant (WWTP) in Wuhan, an A/A/O process model was established based on activated sludge/anaerobic digestion model (ASDM), and the denitrification was optimized and simulated by using historical data. The influencing factors, such as reflux ratio of nitrifying liquid (0-600%), dissolved oxygen (DO) in aerobic zone (1-6 mg/L), DO in anoxic zone (0.005-0.2 mg/L) and temperature (16-29 ℃), were simulated and analyzed. The optimal operational parameters were as follows: reflux ratio of nitrification liquid of 100%, DO in aerobic zone of 1 mg/L, sludge reflux ratio of 65%, and sludge discharge amount of 550 m/d. It was found that low DO in the anoxic zone was more conducive to nitrogen removal. According to the above conclusions and the actual situation of the WWTP, the optimized plan was determined as follows: nitrifying liquid reflux ratio of 300%, DO in the aerobic zone of less than 3 mg/L, closing aerator before the nitrifying liquid reflux point to reduce DO in anoxic zone, and carbon source dosage (calculated by COD) of 90 kg/d. After two months of actual operation, the denitrification performance was improved obviously, and 100% of the total nitrogen samples reached the discharge standard.
Last Update:
2022-01-01