WANG Xiao-ting,LI Xiao-ling,LU Zhao-lin,et al.Effect of S/N Ratio on Dissimilatory Nitrite Reduction Process in Activated Sludge System[J].China Water & Wastewater,2021,37(23 23):95-100.
Effect of S/N Ratio on Dissimilatory Nitrite Reduction Process in Activated Sludge System
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第37卷
Number:
23 23
Page:
95-100
Column:
Date of publication:
2021-12-01
- Keywords:
- sulfur autotrophic denitrification; S/N ratio; dissimilatory nitrite reduction to ammonia(DNRA); oxidation-reduction potential (ORP); microbial community analysis
- Abstract:
- Dissimilatory nitrite reduction to ammonia (DNRA), an important component of nitrate dissimilatory reduction pathway, has attracted much attention. To explore the effect of sulfur on denitrification and DNRA process in activated sludge system, effect of different S/N ratio on nitrate dissimilation reduction pathway in activated sludge system was analyzed by using sodium sulfide as electron donor and nitrate as electron acceptor. When S/N ratio was 1.0, sulfur autotrophic denitrification process was dominated in the system. When S/N ratios were 1.3, 1.5, 1.7 and 2.0, respectively, both sulfur autotrophic denitrification and DNRA processes occurred simultaneously in the system, and the proportion of DNRA (PDNRA) reached the maximum when S/N ratio was 1.7. The results indicated that DNRA occurred when the electron donor was sufficient in the activated sludge sulfur autotrophic denitrification system, and the PDNRA changed with the ratio of electron donor to acceptor. Oxidation-reduction potential (ORP) of the system could indicate the nitrate reduction process to some extent, and lower ORP was more beneficial to DNRA occurrence. Thiobacills,Hydrogenophilaceae,Pseudoxanthomonas and Burkholderiaceae were main microbial community of the process of sulfur autotrophic denitrification and DNRA, further confirming the occurrence of DNRA process.
Last Update:
2021-12-01