Research on the large-scale application of nitrogen removal for the treatment of synthetic ammonia wastewater

Abstract

The capability of anoxic–aerobic (A/O) process treatment and influencing factors of high concentration ammonia industrial wastewater were studied in this paper. Results showed that the A/O process system had achieved favorable performance and the quality of effluent could meet the direct emission standard of Discharge standard of water pollutants for ammonia industry (GB13458-2013) under the optimal conditions as follows: the perfect inflow loading of ammonia 0.12 kg/(m³ d), the mixed liquid recycle ratio (R) 200%, and sludge return ratio 80%, the carbon-to-nitrogen ratio (C/N ratio) 4.5–5.5. Besides, the results also confirmed that the activity of nitrifying bacteria in activated sludge was greatly inhibited due to the high concentration of free ammonia (FA). In addition, carbon shortage had a marked effect on the denitrification efficiency of the system.

Keywords:

• High-content ammonia nitrogen
• Synthetic ammonia wastewater
• Nitrogen removal
• C/N ratio
• Ammonia loading

Acknowledgments

This work was financially supported by the National Nature Science Foundation of China (NSFC) (No. 51208397), the Fundamental Research Funds for the Central Universities (2013-IV-055), and Independent Innovation Fund for Wuhan University of Technology (No. 145206011).