US EPA

9420085 

Journal Article 

3DBER系统功能强化与协同作用机制研究 

Wu, XY; Li, JW; Hao, RX; Zheng, XY 

2021 

1 

Zhongguo Huanjing Kexue / China Environmental Science
ISSN: 1000-6923 

Chinese Society for Environmental Sciences 

41 

6 

2610-2621 

Chinese 

The effluent from the secondary biological treatment of sewage plant usually has a low C/N ratio and low biodegradability, additional carbon sources should be added in its deep denitrification process. To address this problem and meet the sewage recycling technology demand for the deep removal of total nitrogen (TN), total phosphorus (TP), and micro-pollutants in the secondary treatment effluent, a multifunctional composite denitrification system based on three-dimensional biofilm electrode reactor process (3DBER) was developed in this study by changing the composition of filler materials in the traditional 3DBER. This new system could achieve enhanced denitrification and simultaneous removal of phosphorus and micro-pollutants (dibutyl phthalate (DBP) and o-benzene Dicarboxylic acid (2-ethylhexyl) ester (DEHP), which were represented by PAEs). The technical approaches of the multifunctional 3DBER process and the corresponding micro-action mechanisms for pollutant removal were examined from the perspectives of process performance and microbial population distribution. The results showed that the sulfur/iron composite functional filler was a key factor for achieving deep denitrification and simultaneous removal of phosphorus and micro pollutants for the secondary biological treatment effluent with a low C/N ratio. The denitrification efficiency of the multifunctional composite system increased by about 20% compared with the traditional 3DBER process, the simultaneous TP removal rate reached 80% and the PAEs removal rate were above 90%. The analysis from chemometrics and molecular biology technologies showed that there was a synergistic promotion effect among microbial ecology, electron donor compensation, and pH balance in the process of denitrification and phosphorus removal. The function of nitrogen removal was due to the joint action of heterotrophic and various autotrophic denitrification, and the key to phosphorus removal was the continuous corrosion of sponge iron. The removal of PAEs was the result of the synergistic effect of adsorption, electrochemical oxidation, and biodegradation. The results can provide theoretical and technical guidance for developing advanced treatment processes for the simultaneous denitrification, phosphorus removal, and micro pollutant removal from secondary biological treatment effluent. © 2021, Editorial Board of China Environmental Science. All right reserved. 

Autotrophic denitrification; Heterotrophic denitrification; Micro pollutants; Nitrogen and phosphorus removal; Three-dimensional biofilm electrode reactor; Biochemical engineering; Biodegradability; Biodegradation; Biological sewage treatment; Bioremediation; Corrosion; Denitrification; Effluent treatment; Effluents; Electrochemical oxidation; Esters; Fillers; Molecular biology; Nitrogen removal; Phosphorus; Plants (botany); Sewage; Sewage treatment plants; Sponge iron; Storm sewers; Autotrophic denitrification; Biofilm-electrode reactor; Denitrification efficiencies; Denitrification process; Multifunctional composites; Multifunctional systems; Performance enhancements; Secondary biological treatments; Biological water treatment