CHENYa-song,ZHAOZheng.Diagnosis of Nitrogen Removal in Modified A2/O+A/O Process and Its Optimization Strategy[J].China Water & Wastewater,2022,38(21):64-71.
Diagnosis of Nitrogen Removal in Modified A2/O+A/O Process and Its Optimization Strategy
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第38卷
Number:
第21期
Page:
64-71
Column:
Date of publication:
2022-11-01
- Keywords:
- A2/O+A/O process; nitrogen removal; optimal regulation; control factor; wastewater treatment plant
- Abstract:
- In view of the increasingly stringent requirements of total nitrogen discharge in wastewater treatment plants, the nitrogen removal of an A2/O+A/O process was diagnosed and analyzed in a comprehensive wastewater treatment plant. Anoxic zone and pre-anoxic zone were the main areas of nitrogen removal, which contributed 55.7%-60.8% and 19.4%-28.5% of the nitrogen removal respectively in different periods. Denitrification in the anoxic zone was unstable, and the effluent NO3--N was greater than 1.6 mg/L with a frequency as high as 35.5%. The actual removal rate of NO3--N in the post-anoxic zone was only 13.9%. A control equation for total nitrogen removal was established based on the diagnosis and analysis of long-term operational data. The key control factors affecting nitrogen removal were internal and external reflux ratio, effluentNO3--N concentration of the anoxic zone and the removal amount of NO3--N in the post-anoxic zone. The total nitrogen in effluent from the wastewater treatment plant could be less than 6 mg/L after process optimization.
Last Update:
2022-11-01