Multiscale Characterization of Anammox Granules and Microbial Migration Under Variable Nitrogen Loading Rates
Abstract
:1. Introduction
2. Material and Methods
2.1. Experiment Setup
2.2. Reactor Operation
2.3. Synthetic Wastewater and Inoculum Sludge
2.4. Properties of AnGS with Different Particle Sizes
2.5. Analytical and Calculative Methods
2.6. Microbal Community Analysis
3. Results and Discussion
3.1. Overall Performance
3.2. Physicochemical Properties of AnGS
3.2.1. Morphology of AnGS at Different Sizes
3.2.2. Percentage of Granular Sludge
3.2.3. Sludge Settling Velocity
3.2.4. Specific Anammox Activity
3.3. Microbial Community
3.3.1. Taxonomic Results
3.3.2. Interrelationships Between Major Microbial Communities
3.3.3. Pearson’s Correlation Analysis Between Genera and Environmental Factors
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Data Availability Statement
Conflicts of Interest
Nomenclature
VSS | volatile suspended solids |
SS | suspended solids |
HRT | hydraulic retention time |
TN | total nitrogen |
Anammox | anaerobic ammonium oxidation |
AnAOB | anammox bacteria |
NLR | nitrogen loading rate |
HAP | hydroxyapatite |
SAA | specific anammox activity |
TNRE | total nitrogen removal efficiency |
PCA | principal component analysis |
SV | settling velocity |
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Phase | Days (d) | Operation Conditions | Reactor Performance | ||||||
---|---|---|---|---|---|---|---|---|---|
TNin (mg/L) | NO2−in:NH4+in | HRT (h) | NLR (gN/L/d) | NH4+eff (mg/L) | NO2−eff (mg/L) | NO3−eff (mg/L) | TNRE (%) | ||
I | 1–47 | 450 | 1:1 | 12 | 0.9 | 28.98 ± 11.91 | 10.26 ± 4.71 | 31.87 ± 7.44 | 82.69 ± 1.92 |
II | 48–123 | 450 | 1.15:1 | 12 | 0.9 | 45.47 ± 16.90 | 9.11 ± 6.31 | 53.53 ± 9.37 | 79.28 ± 0.27 |
III | 124–154 | 450 | 1.2:1 | 3 | 3.6 | 16.90 ± 7.976 | 20.03 ± 13.69 | 51.79 ± 3.17 | 83.64 ± 0.59 |
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Fan, X.; Qian, Y.; Yang, X.; Wang, Y.; Yang, H.; He, S. Multiscale Characterization of Anammox Granules and Microbial Migration Under Variable Nitrogen Loading Rates. Water 2025, 17, 1653. https://doi.org/10.3390/w17111653
Fan X, Qian Y, Yang X, Wang Y, Yang H, He S. Multiscale Characterization of Anammox Granules and Microbial Migration Under Variable Nitrogen Loading Rates. Water. 2025; 17(11):1653. https://doi.org/10.3390/w17111653
Chicago/Turabian StyleFan, Xiaoliang, Yunzhi Qian, Xueying Yang, Yilin Wang, Hong Yang, and Shilong He. 2025. "Multiscale Characterization of Anammox Granules and Microbial Migration Under Variable Nitrogen Loading Rates" Water 17, no. 11: 1653. https://doi.org/10.3390/w17111653
APA StyleFan, X., Qian, Y., Yang, X., Wang, Y., Yang, H., & He, S. (2025). Multiscale Characterization of Anammox Granules and Microbial Migration Under Variable Nitrogen Loading Rates. Water, 17(11), 1653. https://doi.org/10.3390/w17111653