Abstract:A new multiple-inflow A1/O2/A3/A4/O5 sludge-biofilm coupling process and its pilot facility were developed and designed for the denitrification and phosphorus removal from domestic sewage with low C/N ratio in the towns of South China. At the inlet flow ratio of 4: 6 between inlet point 1 and inlet point 2, the influence of the mixed liquid reflux ratio on the removal of organic matter, nitrogen and phosphorus in the system and the rule of nitrogen transformation were studied. The results showed that when the average C/N ratio was 2.09 and the mixed refluent ratio was 300%, the average values of COD, ${\rm{NH}}_4^ + $-N, TN and TP in the effluent were 23.45, 0.80, 12.41 and 0.36 mg·L?1, respectively, and the corresponding average removal rates were 86.88%, 98.25%, 77.68% and 90.31%, respectively. Compared with multi-stage inflow A/O/A/A/O sludge-biofilm coupling process, the TN removal rate of the system increased from 68.28% to 77.68% and the TP removal rate increased from 75.22% to 90.31% after the mixed liquid reflux increased. This system has significant advantages in denitrification and phosphorus removal from low carbon nitrogen ratio sewage, and solves the problem that the phosphorus effluent is difficult to be below 0.5 mg/L in the biological treatment of low carbon and nitrogen ratio sewage. Key words:multi-point water inlet/ mixed liquid reflux ratio/ A1/O2/A3/A4/O5 sludge-biofilm coupling process/ low C/N ratio/ urban sewage/ denitrification and phosphorus removal.
图1多点进水新型A1/O2/A3/A4/O5泥膜耦合工艺流程 Figure1.Process flow diagram of a new multiple-inflow A1/O2/A3/A4/O5 sludge-biofilm coupling process
图5各工况下${{\rm{NH}}_4^ +} $-N、${{\rm{NO}}_3^ -} $-N沿程的变化规律 Figure5.${{\rm{NH}}_4^ + }$-N, ${{\rm{NO}}_3^ - }$-N concentration at different stages under different operational conditions
ZHANG W, JIN X, LIU D, et al. Temporal and spatial variation of nitrogen and phosphorus and eutrophication assessment for a typical arid river-Fuyang River in northern China[J]. Journal of Environmental Science, 2017, 55(5): 41-48.
[2]
ABYAR H, YOUNESI H, BAHRAMIFAR N, et al. Biological CNP removal from meat-processing wastewater in an innovative high rate up-flow A2O bioreactor[J]. Chemosphere, 2018, 213(12): 197-204.
[3]
JI B, ZHANG X, ZHANG S, et al. Insights into the bacterial species and communities of a full-scale anaerobic/anoxic/oxic wastewater treatment plant by using third-generation sequencing[J]. Journal of Bioscience and Bioengineering, 2019, 128(6): 744-750. doi: 10.1016/j.jbiosc.2019.06.007
[4]
NATALIA R M, BADIA F M, GUISASOLA A, et al. Glutamate as sole carbon source for enhanced biological phosphorus removal[J]. Science of the Total Environment, 2018, 657(1): 1398-1408.
BOYLE C A, MCKENZIE C J, MORGAN S. Internal recycle to improve denitrification in a step feed anoxic/aerobic activated sludge system[J]. Water Science & Technology, 2009, 60(7): 1661-1668.
1.School of Energy and Enviroment, Anhui University of Technology, Ma′anshan 243002, China 2.Anhui Huaqi Environmental Protection Technology Co. Ltd., Ma′anshan 243061, China 3.BAF Engineering Technology Research Center of Anhui Province, Ma′anshan 243061, China Received Date: 2020-11-22 Accepted Date: 2021-03-04 Available Online: 2021-05-23 Keywords:multi-point water inlet/ mixed liquid reflux ratio/ A1/O2/A3/A4/O5 sludge-biofilm coupling process/ low C/N ratio/ urban sewage/ denitrification and phosphorus removal Abstract:A new multiple-inflow A1/O2/A3/A4/O5 sludge-biofilm coupling process and its pilot facility were developed and designed for the denitrification and phosphorus removal from domestic sewage with low C/N ratio in the towns of South China. At the inlet flow ratio of 4: 6 between inlet point 1 and inlet point 2, the influence of the mixed liquid reflux ratio on the removal of organic matter, nitrogen and phosphorus in the system and the rule of nitrogen transformation were studied. The results showed that when the average C/N ratio was 2.09 and the mixed refluent ratio was 300%, the average values of COD, ${\rm{NH}}_4^ + $-N, TN and TP in the effluent were 23.45, 0.80, 12.41 and 0.36 mg·L?1, respectively, and the corresponding average removal rates were 86.88%, 98.25%, 77.68% and 90.31%, respectively. Compared with multi-stage inflow A/O/A/A/O sludge-biofilm coupling process, the TN removal rate of the system increased from 68.28% to 77.68% and the TP removal rate increased from 75.22% to 90.31% after the mixed liquid reflux increased. This system has significant advantages in denitrification and phosphorus removal from low carbon nitrogen ratio sewage, and solves the problem that the phosphorus effluent is difficult to be below 0.5 mg/L in the biological treatment of low carbon and nitrogen ratio sewage.