Nitrogen Removal for Low Concentration Ammonium Wastewater by Adsorption, Shortcut Simultaneous Nitrification and Denitrification Process in MBBR
Abstract
:1. Introduction
2. Materials and Methods
2.1. Wastewater Composition and Carrier
2.2. Experimental Set-Up and Operation of the MBBR
2.3. Technological Process
2.4. Experimental Design
2.4.1. Study on the Operational Performance at the MBBR Adsorption Stage
- (1)
- Effect of hydraulic retention time (HRT) on the treatment effect of the MBBR in the adsorption stage.
- (2)
- Effect of stirring speed on the adsorption of ammonia and nitrogen by ceramsite.
2.4.2. Study on the Operational Performance at the MBBR Shortcut SND Denitrification and Regeneration Stage
- (1)
- Effect of alkalinity dosage ratio on the MBBR shortcut SND denitrification and regeneration.
- (2)
- Effect of DO on the MBBR shortcut SND denitrification and regeneration.
2.5. Water Quality Analysis Method
2.6. Detection and Calculation of Ceramsite Desorption Amount
2.7. Calculation of Relevant Indicators for Each Stage
2.7.1. Adsorption Stage
- (1)
- Integral value of adsorption curve
- (2)
- Accumulated ammonia nitrogen effluent
- (3)
- Accumulated ammonia nitrogen influent
- (4)
- Ammonia volume load
2.7.2. Shortcut SND Denitrification and Regeneration Stage
- (1)
- Theoretical alkalinity dosage
- (2)
- Simultaneous nitrification and denitrification rate
- (3)
- Nitrite accumulation ratio
- (4)
- Total nitrogen removal rate
- (5)
- Ammonia removal rate
- (6)
- Regeneration rate of bio-ceramsite
- (7)
- Average regeneration speed of bio-ceramsite at 12 h
- (8)
- FA concentration
2.8. Statistical Analysis
3. Results and Discussion
3.1. Study on the Operational Performance at the MBBR Adsorption Stage
3.1.1. Effect of Hydraulic Retention Time on the Adsorption Performance of the MBBR
3.1.2. Effect of Stirring Speed on the Adsorption Performance of the MBBR
3.2. Study on the Operational Performance at MBBR Shortcut SND Denitrification and Regeneration Stage
3.2.1. Effect of Alkalinity Dosage Ratio on MBBR Shortcut SND Denitrification and Regeneration
3.2.2. Effect of DO on the MBBR Shortcut SND Denitrification and Regeneration
3.3. The Optimum Conditions and the Mechanism of the MBBR Adsorption-Shortcut SND Process
4. Conclusions
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Primary Nutrients | Trace Elements | ||
---|---|---|---|
Component | Concentration (mg/L) | Component | Concentration (mg/L) |
100 | CuSO4 | 0.005 | |
glucose | 167 | CoCl2·6H2O | 0.021 |
NaHCO3 | 107 | Na2MoO4·2H2O | 0.016 |
KH2PO4 | 10.2 | ZnSO4·7H2O | 0.041 |
FeSO4·7H2O | 2.51 | H3BO3 | 0.15 |
MgSO4·7H2O | 5.71 | MnCl·4H2O | 0.211 |
CaCl2·7H2O | 1.54 | Vitamin D | 0.0002 |
Parameters | HRT = 12 h | HRT = 8 h | HRT = 6 h |
---|---|---|---|
Influent -N concentration (mg/L) | 26.18 ± 0.11 | 26.20 ± 0.08 | 26.24 ± 0.12 |
Adsorption breakthrough time (h) | 34 | 20 | 14 |
Adsorption breakthrough concentration (mg/L) | 5.40 ± 0.65 | 5.01 ± 0.34 | 5.82 ± 0.44 |
Integral value of adsorption curve (mg·h/L) | 65.46 | 26.49 | 17.91 |
Input flow rate (L/h) | 0.5 | 0.75 | 1 |
Cumulative -N effluent (mg) | 32.73 | 19.87 | 17.91 |
Cumulative -N influent (mg) | 602.14 ± 1.72 | 550.20 ± 1.57 | 524.80 ± 1.13 |
Unit adsorption quantity (mg/g) | 1.0910 ± 0.0023 a | 1.0143 ± 0.0016 b | 0.9566 ± 0.0011 c |
-N volume load (mg/(L·h)) | 0.7706 ± 0.0019 a | 1.3100 ± 0.0023 b | 1.8714 ± 0.0035 c |
Parameters | 60 r/min | 90 r/min | 120 r/min | 150 r/min |
---|---|---|---|---|
Influent -N concentration (mg/L) | 26.22 ± 0.07 | 26.19 ± 0.08 | 26.15 ± 0.11 | 26.16 ± 0.10 |
HRT (h) | 8 | 8 | 8 | 8 |
Adsorption breakthrough time (h) | 18 | 20 | 22 | 24 |
Adsorption breakthrough concentration (mg/L) | 5.21 ± 0.17 | 5.03 ± 0.14 | 5.08 ± 0.20 | 5.89 ± 0.15 |
Integral value of adsorption curve (mg·h/L) | 25.18 | 27.29 | 28.43 | 32.78 |
Cumulative -N effluent (mg) | 18.89 | 20.47 | 21.32 | 24.59 |
Cumulative -N influent (mg) | 511.29 ± 1.15 | 549.99 ± 1.46 | 588.38 ± 2.09 | 627.84 ± 2.07 |
Unit adsorption quantity (mg/g) | 0.9354 ± 0.0016 a | 1.0143 ± 0.0024 b | 1.0912 ± 0.0038 c | 1.1546 ± 0.0045 d |
-N volume load (mg/(L·h)) | 1.4556 ± 0.0032 a | 1.3100 ± 0.0028 b | 1.1909 ± 0.0019 c | 1.0917 ± 0.0015 d |
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Wang, L.; Mao, X.; Hamoud, Y.A.; Zhu, N.; Shao, X.; Wang, Q.; Shaghaleh, H. Nitrogen Removal for Low Concentration Ammonium Wastewater by Adsorption, Shortcut Simultaneous Nitrification and Denitrification Process in MBBR. Water 2023, 15, 1334. https://doi.org/10.3390/w15071334
Wang L, Mao X, Hamoud YA, Zhu N, Shao X, Wang Q, Shaghaleh H. Nitrogen Removal for Low Concentration Ammonium Wastewater by Adsorption, Shortcut Simultaneous Nitrification and Denitrification Process in MBBR. Water. 2023; 15(7):1334. https://doi.org/10.3390/w15071334
Chicago/Turabian StyleWang, Liangkai, Xinyu Mao, Yousef Alhaj Hamoud, Ningyuan Zhu, Xiaohou Shao, Qilin Wang, and Hiba Shaghaleh. 2023. "Nitrogen Removal for Low Concentration Ammonium Wastewater by Adsorption, Shortcut Simultaneous Nitrification and Denitrification Process in MBBR" Water 15, no. 7: 1334. https://doi.org/10.3390/w15071334
APA StyleWang, L., Mao, X., Hamoud, Y. A., Zhu, N., Shao, X., Wang, Q., & Shaghaleh, H. (2023). Nitrogen Removal for Low Concentration Ammonium Wastewater by Adsorption, Shortcut Simultaneous Nitrification and Denitrification Process in MBBR. Water, 15(7), 1334. https://doi.org/10.3390/w15071334