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Zeng M, Li Z, Cheng Y, Luo Y, Hou Y, Wu J, Long B. Stability of aerobic granular sludge for treating inorganic wastewater with different nitrogen loading rates. ENVIRONMENTAL TECHNOLOGY 2024; 45:3898-3911. [PMID: 37470502 DOI: 10.1080/09593330.2023.2237656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 07/02/2023] [Indexed: 07/21/2023]
Abstract
This paper investigated the effect of nitrogen loading rates (NLRs) on the stability of aerobic granular sludge (AGS) for treating simulated ionic rare earth mine wastewater with high ammonia nitrogen and extremely low organic content. Mature AGS from a sequencing batch reactor (SBR) was seeded into five identical SBRs (R1, R2, R3, R4 and R5). The five reactors were operated with different NLRs (0.2, 0.4, 0.8, 1.2 and 1.6 kg/m3·d). After 30 days of operation, R1, R2 and R5 were dominated by broken granules, while most of the granules in R3 and R4 still maintained a complete structure. The properties of granules from R1, R2, R3, R4 and R5 deteriorated to varying degrees, while the granules from R3 and R4 showed better stability than that from R1, R2 and R5. In R1, R2, R3 and R4, the steady-state ammonia nitrogen removal efficiencies were all greater than 90%, and the steady-state removal efficiencies of total inorganic nitrogen (TIN) were approximately 30%. In R5, the removal efficiencies of ammonia nitrogen and TIN were both approximately 70%. The dominant nitrifying and denitrifying bacterial genera of the granules from the five reactors were Nitrosomonas and Thauera, respectively, and their relative abundance was much higher in granules from R3 and R4. The results demonstrated that a relative equilibrium between the growth and metabolism of nitrifying/denitrifying bacteria was achieved when NLR was between 0.8 and 1.2 kg/m3·d, which could provide technical support for the stability maintenance of AGS in the treatment of ionic rare earth mine wastewater.
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Affiliation(s)
- Mingjing Zeng
- School of Civil and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou, People's Republic of China
| | - Zhenghao Li
- School of Civil and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou, People's Republic of China
| | - Yuanyuan Cheng
- School of Civil and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou, People's Republic of China
| | - Yi Luo
- School of Civil and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou, People's Republic of China
| | - Yiran Hou
- School of Civil and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou, People's Republic of China
| | - Junfeng Wu
- Henan Province Key Laboratory of Water Pollution Control and Rehabilitation Technology, Pingdingshan, People's Republic of China
| | - Bei Long
- School of Civil and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou, People's Republic of China
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Li Z, Cheng Y, Zeng M, Luo Y, Hou Y, Wu J, Nie J, Long B. Effect of in situ ultrasonic wave and influent ammonia nitrogen fluctuation on stability of aerobic granular sludge. ENVIRONMENTAL TECHNOLOGY 2023:1-14. [PMID: 38008972 DOI: 10.1080/09593330.2023.2283087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 09/09/2023] [Indexed: 11/28/2023]
Abstract
This study elucidates the impact of fluctuating influent conditions and in situ ultrasonic wave exposure on the stability of aerobic granular sludge (AGS) in the treatment of simulated wastewater emanating from rare earth mining operations. During a stable influent period spanning from Day 1 to Day 95, the seed granules underwent an initial disintegration followed by a re-granulation phase. The secondary granulation was achieved on Day 80 and Day 40 for the ultrasonic reactor (R1) and the control reactor (R2), respectively. Notably, granules formed in R1 exhibited a more porous structure compared to those generated in R2. Subsequently, when the ammonia nitrogen in the influent oscillated between 100 and 500 mg/L during Days 96-140, both reactors yielded compact and densely structured granules. Nitrogen removal profiles were comparable between the two reactors: the removal efficiencies for ammonia nitrogen and total inorganic nitrogen escalated from 95% and 80%, respectively, during Days 1-95, to 95% and 90%, respectively, post-Day 140. A suite of performance metrics indicated that steady-state granules from R1 outperformed those from R2 across several parameters. Specifically, the nitrification/denitrification rates, and relative abundance of denitrifying bacteria were all higher in granules from R1. Conversely, the relative abundance of nitrifying bacteria was comparable between granules from both reactors. However, R1 granules demonstrated lower sludge concentration and smaller average particle size than their R2 counterparts. In conclusion, the AGS system demonstrated robust resilience to fluctuating ammonia nitrogen, and the application of ultrasonic waves significantly enhanced granular activity while achieving in situ sludge reduction.
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Affiliation(s)
- Zhenghao Li
- School of Civil and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou, People's Republic of China
| | - Yuanyuan Cheng
- School of Civil and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou, People's Republic of China
| | - Mingjing Zeng
- School of Civil and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou, People's Republic of China
| | - Yi Luo
- School of Civil and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou, People's Republic of China
| | - Yiran Hou
- School of Civil and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou, People's Republic of China
| | - Junfeng Wu
- Henan Key Laboratory of Water Pollution Control and Rehabilitation Technology, Pingdingshan, People's Republic of China
| | - Jiale Nie
- School of Civil and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou, People's Republic of China
| | - Bei Long
- School of Civil and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou, People's Republic of China
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Zeng Y, Zeng M, Cheng Y, Long B, Wu J. Cultivation of autotrophic nitrifying granular sludge for simultaneous removal of ammonia nitrogen and Tl(I). ENVIRONMENTAL TECHNOLOGY 2023; 44:4017-4032. [PMID: 35574708 DOI: 10.1080/09593330.2022.2077659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Accepted: 05/05/2022] [Indexed: 06/15/2023]
Abstract
Autotrophic nitrifying granular sludge (ANGS) was cultivated for the simultaneous removal of ammonia nitrogen and Tl(I) from inorganic wastewater. The chemical oxygen demand (COD) in the influent gradually decreased to approximately zero in four parallel sequencing batch reactors (B1: blank controller, B2: 10 mL of added nitrifying bacteria concentrate in each cycle, B3: 1 mg/L Tl(I) added in each cycle and B4: 10 mL of added nitrifying bacteria concentrate and 1 mg/L Tl(I) in each cycle) within 15 days. The main properties, such as the granulation rate and specific oxygen uptake rate (SOUR) of the ANGS in B1, B2, B3 and B4 tended to be stable within 40, 33, 30 and 33 days, the removal efficiencies of Tl(I) were 59.5%-82.9% and 57.1%-88.6% in B3 and B4 after Day 30, the removal efficiencies of ammonia nitrogen in B1, B2, B3 and B4 were usually above 90% after Day 33, and the total inorganic nitrogen (TIN) in the effluent of B1, B2, B3 and B4 gradually stabilized after Day 36, 32, 32 and 36, indicating that mature ANGS was successfully cultivated in B1, B2, B3 and B4 within 40, 33, 33 and 36 days. The nitrogen degradation kinetic parameters of ANGS indicated that B3 had the strongest ability to remove ammonia and nitrite, suggesting that Tl(I) stress was beneficial to ammonia nitrogen removal and nitrite oxidation. The adsorption of Tl(I) can be described by the Freundlich equation, and the addition of external nitrifying bacteria improved the adsorption ability of ANGS.
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Affiliation(s)
- Yu Zeng
- School of Civil and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou, People's Republic of China
| | - Mingjing Zeng
- School of Civil and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou, People's Republic of China
| | - Yuanyuan Cheng
- School of Civil and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou, People's Republic of China
| | - Bei Long
- School of Civil and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou, People's Republic of China
| | - Junfeng Wu
- Henan Province Key Laboratory of Water Pollution Control and Rehabilitation Technology, Pingdingshan, People's Republic of China
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Zeng M, Zeng Y, Zhang B, Cheng Y, Long B, Wu J, Ren S, Liu Y. Coupling of endogenous/exogenous nitrification and denitrification in an aerobic granular sequencing batch reactor. ENVIRONMENTAL TECHNOLOGY 2023; 44:3641-3655. [PMID: 35439111 DOI: 10.1080/09593330.2022.2068380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Accepted: 04/02/2022] [Indexed: 06/14/2023]
Abstract
The performance of endogenous/exogenous nitrification and denitrification in an aerobic granular sequencing batch reactor was investigated for treating inorganic wastewater with ammonia nitrogen of 250 mg/L. The sequencing batch reactor with an effective volume of 120.5 L was started by seeding autotrophic nitrifying granular sludge (ANGS) and operated under oxic (110 min)/anoxic (120 min)/oxic (110 min) aeration mode. The total inorganic nitrogen (TIN) removal efficiency of ANGS was between 60% and 70% without external carbon sources in days 1-25. However, the operation mode was unsustainable as endogenous nitrification and denitrification would lead to an obvious decrease of sludge concentration. After sodium acetate (the contributed chemical oxygen demand in the reactor was 250-300 mg/L) was added at the beginning of the anaerobic/anoxic stage from day 26, aerobic granules were inadaptable in a few days, which resulted in particle disintegration and SVI increase. As microbes gradually acclimated to the new environment, the aerobic granular sludge became smoother and denser, the relative abundance of denitrifying bacteria increased to 66.07%, and the removal efficiency of TIN gradually increased to more than 90% from day 89. Contributions of endogenous/exogenous nitrification and denitrification to TIN removal were 54.09% and 46.01%, respectively. The coupling of endogenous/exogenous nitrification and denitrification could reduce the aeration consumption, save the external carbon source dosage and decrease the alkalinity consumption, which provided another option for treating wastewater from ionic rare earth mine.
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Affiliation(s)
- Mingjing Zeng
- School of Civil and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou, People's Republic of China
| | - Yu Zeng
- School of Civil and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou, People's Republic of China
| | - Binchao Zhang
- School of Civil and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou, People's Republic of China
| | - Yuanyuan Cheng
- School of Civil and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou, People's Republic of China
| | - Bei Long
- School of Civil and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou, People's Republic of China
| | - Junfeng Wu
- Henan Province Key Laboratory of Water Pollution Control and Rehabilitation Technology, Pingdingshan, People's Republic of China
| | - Shuai Ren
- School of Civil and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou, People's Republic of China
| | - Yong Liu
- School of Civil and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou, People's Republic of China
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Cultivation of Nitrifying and Nitrifying-Denitrifying Aerobic Granular Sludge for Sidestream Treatment of Anaerobically Digested Sludge Centrate. Processes (Basel) 2022. [DOI: 10.3390/pr10091687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
In this study, three 1.2-L aerobic granular sludge sequencing batch reactors (AGS-SBRs) were used to cultivate nitrifying and nitrifying-denitrifying granules (w/supplemental carbon) and investigate sidestream treatment of synthetic-centrate and real-centrate samples from Ashbridges Bay Treatment Plant (ABTP) in Toronto, Ontario, Canada. Results showed that although the cultivation of distinct granules was not observed in the nitrifying reactors, sludge volume index (SVI30) values achieved while treating real and synthetic centrate were 72 ± 12 mL/g and 59 ± 11 mL/g (after day 14), respectively. Ammonia-nitrogen (NH3-N) removal in the nitrifying SBRs were 93 ± 19% and 94 ± 16% for real and synthetic centrate, respectively. Granules with a distinct round structure were successfully formed in the nitrifying-denitrifying SBR, resulting in an SVI30 of 52 ± 23 mL/g. NH3-N, chemical oxygen demand (COD) and phosphorus (P) removal in the nitrifying-denitrifying SBR were 92 ± 9%, 94 ± 5%, and 81 ± 14% (7th to 114th day), respectively with a low nitrite (NO2-N) and nitrate (NO3-N) concentration in the effluent indicating simultaneous nitrification-denitrification (SND) activity. High nutrient removal efficiencies via the nitrification and SND pathways shows that AGS technology is a viable process for treating sidestreams generated in a WWTP.
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Peng Z, Lou T, Jiang K, Niu N, Wang J, Li L. Nitrification characteristics of long-term idle aerobic activated sludge during domestication. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:23386-23394. [PMID: 33447971 DOI: 10.1007/s11356-020-12297-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 12/29/2020] [Indexed: 06/12/2023]
Abstract
Nitrite accumulation usually occurred when domesticating the idle aerobic activated sludge. A sequencing batch reactor (SBR) was used to investigate whether the short-cut nitrification sludge could be cultivated using the idle sludge as inoculated sludge. The results showed that the nitrification process consisted of three stages. In the first stage, the activity of ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) were very low with almost no nitrification performance. In the second stage, the activity of AOB started to recover with the effluent NH4+-N gradually decreased to 0.29 mg L-1, while NOB was alternately inhibited by free ammonia (FA), free nitrous acid (FNA), and nitrite. The effluent NOx--N was mainly NO2--N with an average nitrite accumulation ratio of 74.00%. In the third stage, the nitrification altered from short-cut nitrification to complete nitrification, and the nitrification kinetics of AOB and NOB were both well-fitted to the Monod equation (R2 > 0.92). The variations of effluent pH and ORP between cycles could indicate the recovery stage of the nitrifying ability. Through monitoring the curves of effluent pH and ORP, when the domestication process is between the pH peak and ORP plateau, the short-cut nitrification sludge could be cultivated. This study revealed the mechanism of nitrite accumulation during the domestication of long-term idle aerobic activated sludge, and established a control strategy to accelerate the domestication.
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Affiliation(s)
- Zhaoxu Peng
- School of Water Conservancy & Environmental Engineering, Zhengzhou University, Zhengzhou, 450001, China.
| | - Tianyu Lou
- School of Water Conservancy & Environmental Engineering, Zhengzhou University, Zhengzhou, 450001, China
| | - Kun Jiang
- School of Water Conservancy & Environmental Engineering, Zhengzhou University, Zhengzhou, 450001, China
| | - Ningqi Niu
- School of Water Conservancy & Environmental Engineering, Zhengzhou University, Zhengzhou, 450001, China
| | - Ju Wang
- School of Water Conservancy & Environmental Engineering, Zhengzhou University, Zhengzhou, 450001, China
| | - Lei Li
- School of Water Conservancy & Environmental Engineering, Zhengzhou University, Zhengzhou, 450001, China
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