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Pereira Almeida FD, Bandeira de Carvalho C, Mendes Barros AR, Amancio Frutuoso FK, Bezerra Dos Santos A. Aerobic granulation and resource production under continuous and intermittent saline stress. CHEMOSPHERE 2024; 360:142402. [PMID: 38777193 DOI: 10.1016/j.chemosphere.2024.142402] [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: 01/11/2024] [Revised: 05/09/2024] [Accepted: 05/20/2024] [Indexed: 05/25/2024]
Abstract
Three sequential batch reactors (SBR) were operated to evaluate salt addition's impact on granulation, performance, and biopolymer production in aerobic granular sludge (AGS) systems. System R1 was fed without adding salt (control); system R2 operated with saline pulses, i.e., one cycle with salt (2.5 g NaCl/L) addition followed by another without salt; and R3 received continuous supplementation of 2.5 g NaCl/L. The results indicated that the reactors supplemented with salt presented higher concentrations of mixed liquor volatile suspended solids (MLVSS) and better settleability than R1, showing that osmotic pressure contributed to biomass growth, accelerated granulation, and improved physical characteristics. The faster granulation occurred in R2, thus proving the beneficial effects of intermittent salt addition through alternating pulses. Salt addition did not impair the simultaneous removal of carbon, nitrogen, and phosphorus. In fact, R2 showed better carbon removals. In conclusion, continuous or intermittent (pulsed) supplementation of 2.5 g NaCl/L did not lead to increased production of extracellular polymeric substances (EPS) and alginate-like exopolymers (ALE). This outcome could be attributed to the low saline concentration employed, a higher food-to-microorganism (F/M) ratio observed in R1, and possibly greater endogenous consumption of biopolymers in the famine period in R2 and R3 due to the greater solids retention time (SRT). Therefore, this study brings important results that contribute to a better understanding of the effect of salt in continuous dosing or in pulses as a selection pressure strategy to accelerate granulation, as well as the behavior of the AGS systems for saline effluents.
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Affiliation(s)
| | - Clara Bandeira de Carvalho
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | | | | | - André Bezerra Dos Santos
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil.
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2
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Wang J, Ran B, Peng Y, An Q, Zhao B. Evaluation of aerobic granulation performance bioaugmented with the auto-aggregating bacterium Pseudomonas stutzeri strain XL-2 with heterotrophic nitrification-aerobic denitrification capacity. BIORESOURCE TECHNOLOGY 2024; 403:130869. [PMID: 38777236 DOI: 10.1016/j.biortech.2024.130869] [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: 01/09/2024] [Revised: 04/27/2024] [Accepted: 05/19/2024] [Indexed: 05/25/2024]
Abstract
In this study, the possibility of an auto-aggregating bacterium Pseudomonas strain XL-2 with heterotrophic nitrification-aerobic denitrification capacity for improving granulation and nitrogen removal was evaluated. The results showed that the supplementation of strain XL-2 promoted granulation, making R1 (experimental group with strain XL-2) dominated by granules at 14 d, which was 12 days earlier than R2 (control group without strain XL-2). This was attributed to the promotion of extracellular polymeric substances (EPS) secretion, particularly proteins by adding strain XL-2, thereby improving the hydrophobicity of sludge and altering the proteins secondary structures to facilitate aggregation. Meanwhile, adding strain XL-2 improved simultaneous nitrification and denitrification efficiency of R1. Microbial community analysis indicated that strain XL-2 successfully proliferated in aerobic granule sludge and might induce the enrichment of genera such as Flavobacterium and Paracoccus that were favorable for EPS secretion and denitrification, jointly promoting granulation and enhancing nitrogen removal efficiency.
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Affiliation(s)
- Jinyi Wang
- The Key Laboratory of Eco-Environment in Three Gorges Reservoir Region, Chongqing University, Chongqing 400045, PR China; College of Environment and Ecology, Chongqing University, Chongqing 400045, PR China
| | - Binbin Ran
- The Key Laboratory of Eco-Environment in Three Gorges Reservoir Region, Chongqing University, Chongqing 400045, PR China; College of Environment and Ecology, Chongqing University, Chongqing 400045, PR China
| | - Yongxue Peng
- The Key Laboratory of Eco-Environment in Three Gorges Reservoir Region, Chongqing University, Chongqing 400045, PR China; College of Environment and Ecology, Chongqing University, Chongqing 400045, PR China
| | - Qiang An
- The Key Laboratory of Eco-Environment in Three Gorges Reservoir Region, Chongqing University, Chongqing 400045, PR China; College of Environment and Ecology, Chongqing University, Chongqing 400045, PR China
| | - Bin Zhao
- The Key Laboratory of Eco-Environment in Three Gorges Reservoir Region, Chongqing University, Chongqing 400045, PR China; College of Environment and Ecology, Chongqing University, Chongqing 400045, PR China.
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3
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Haaksman VA, van Dijk EJH, Al-Zuhairy S, Mulders M, Loosdrecht MCMV, Pronk M. Utilizing anaerobic substrate distribution for growth of aerobic granular sludge in continuous-flow reactors. WATER RESEARCH 2024; 257:121531. [PMID: 38701553 DOI: 10.1016/j.watres.2024.121531] [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: 11/17/2023] [Revised: 03/24/2024] [Accepted: 03/26/2024] [Indexed: 05/05/2024]
Abstract
The development of continuous flow reactors (CFRs) employing aerobic granular sludge (AGS) for the retrofit of existing wastewater treatment plants (WWTPs) using a continuous-flow activated sludge (CFAS) system has garnered increasing interest. This follows the worldwide adoption of AGS technology in sequencing batch reactors (SBRs). The better settleability of AGS compared to AS allows for process intensification of existing wastewater treatment plants without the difficult conversion of often relatively shallow CFRs to deeper AGS-SBRs. To retrofit existing CFAS systems with AGS, achieving both increased hydraulic capacity and enhanced biological nutrient removal necessitates the formation of granular sludge based on the same selective pressures applied in AGS-SBRs. Previous efforts have focussed mainly on the selective wasting of flocculent sludge and retaining granular sludge to drive aerobic granulation. In this study a pilot-scale CFR was developed to best mimic the implementation of the granulation mechanisms of full-scale AGS-SBRs. The pilot-scale reactor was fed with pre-settled municipal wastewater. We established metrics to assess the degree to which the proposed mechanisms were implemented in the pilot-scale CFR and compared them to data from full-scale AGS-SBRs, specifically with respect to the anaerobic distribution of granule forming substrates (GFS). The selective pressures for granular sludge formation were implemented through inclusion of anaerobic upflow selectors with a water depth of 2.5 meters, which yielded a sludge with properties similar to AGS from full-scale SBRs. In comparison to the CFAS system at Harnaschpolder WWTP treating the same pre-settled wastewater, a more than twofold increase in volumetric removal capacity for both phosphorus and nitrogen was achieved. The use of a completely mixed anaerobic selector, as opposed to an anaerobic upflow selector, caused a shift in EBPR activity from the largest towards the smallest size class, while nitrification was majorly unaffected. Anaerobic selective feeding via bottom-feeding is, therefore, favorable for the long-term stability of AGS, especially for less acidified wastewater. The research underlines the potential of AGS for enhancing the hydraulic and biological treatment capacity of existing CFAS systems.
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Affiliation(s)
- Viktor A Haaksman
- Delfluent Services, Peuldreef 4, Den Hoorn, 2635 BX, The Netherlands.
| | | | - Salah Al-Zuhairy
- Delfluent Services, Peuldreef 4, Den Hoorn, 2635 BX, The Netherlands
| | - Michel Mulders
- Delfluent Services, Peuldreef 4, Den Hoorn, 2635 BX, The Netherlands
| | - Mark C M van Loosdrecht
- Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, Delft, 2629 HZ, The Netherlands
| | - Mario Pronk
- Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, Delft, 2629 HZ, The Netherlands; Royal HaskoningDHV, Laan 1914 35, Amersfoort, 3800 AL, The Netherlands.
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4
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Zou X, Gao M, Yao Y, Zhang Y, Guo H, Liu Y. Efficient nitrogen removal from ammonia rich wastewater using aerobic granular sludge (AGS) reactor: Selection and enrichment of effective microbial community. ENVIRONMENTAL RESEARCH 2024; 251:118573. [PMID: 38431070 DOI: 10.1016/j.envres.2024.118573] [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: 01/04/2024] [Revised: 02/23/2024] [Accepted: 02/26/2024] [Indexed: 03/05/2024]
Abstract
Anaerobically digested sludge supernatant, characterized by its high ammonia and low biodegradable chemical oxygen demand (COD) content, has raised concerns when returned to mainstream treatment lines due to potential impacts on effluent quality. Addressing this, an aerobic granular sludge (AGS) reactor adopted nitritation/denitritation with external COD addition was utilized and achieved a considerable nitrogen treatment capacity of 4.2 kg N/m3/d, reaching over 90% removal efficiencies for both ammonia and total inorganic nitrogen. This study applied progressively increased nitrogen loading to select for a microbial community that exhibited high nitrogen oxidation and reduction rates, demonstrating peak rates of 0.5 g N/g VSS/d and 3 g N/g VSS/d, respectively. The enrichment of highly efficient microbial community was achieved along with the increased biomass density peaked at 17 g/L MLVSS, with the system retaining small-sized granular sludge at 0.5 mm. The primary ammonia oxidizing bacteria was Nitrosomonas, while Thauera was the dominated denitrifiers. Quantitative polymerase chain reaction analyses reinforced the enhanced nitrogen removal capacity based on the progressively increased abundance of nitrogen cycling functional genes. The high nitrogen treatment capacity, synergistic attributes of high specific microbial activities and the substantial biomass retention, suggest the AGS's efficacy and capacity in ammonia rich wastewater treatment.
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Affiliation(s)
- Xin Zou
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta, T6G 1H9, Canada
| | - Mengjiao Gao
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta, T6G 1H9, Canada; College of Environment and Ecology, Chongqing University, Chongqing, China
| | - Yiduo Yao
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta, T6G 1H9, Canada
| | - Yihui Zhang
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta, T6G 1H9, Canada
| | - Hengbo Guo
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta, T6G 1H9, Canada
| | - Yang Liu
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta, T6G 1H9, Canada; School of Civil & Environmental Engineering, Queensland University of Technology, Brisbane, Queensland, Australia.
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Wang C, Qi WK, Zhang SJ, Liu LF, Peng YZ. Innovation for continuous aerobic granular sludge process in actual municipal sewage treatment: Self-circulating up-flow fluidized bed process. WATER RESEARCH 2024; 260:121862. [PMID: 38908310 DOI: 10.1016/j.watres.2024.121862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 05/28/2024] [Accepted: 05/31/2024] [Indexed: 06/24/2024]
Abstract
Aerobic granular sludge (AGS) capable of nitrogen and phosphorus removal is mainly limited to the applications in sequencing batch reactors. This study introduced an innovative continuous self-circulating up-flow fluidized bed process (Zier process) using separate aeration. The process was composed of an anoxic column (Zier-A), aeration column (Zier-OO) and aerobic column (Zier-O), and was used to treat actual municipal sewage continuously for 170 days. The process achieved self-circulation of 20-32 times and an up-flow velocity within the reactor of 7-16 m/h which were accurately controlled with only separate aeration. The larger proportion of self-circulating multiple times contributed to particle formation and stability, providing hydraulic shear conditions, and screened the precipitation performance of the granular sludge (GS). Meanwhile, the dissolved oxygen (DO) of Zier-O was controlled at 0.1-0.3 mg/L, and the DO of Zier-A input water was zero. The accurate oxygen supply enhanced simultaneous nitrification and denitrification (SND) as well as short-cut nitrification and denitrification in Zier-O and improved the COD utilization rate and the nitrogen removal rate in Zier-A. The COD treatment capacity reached 2.46 kg-COD/(m³·d). With a hydraulic retention time of 10 h, the process consistently ensured that the average concentrations of ammonia nitrogen and total nitrogen in the effluent were maintained below 5 and 15 mg/L, respectively. Moreover, the process maintained the shape and stability of GS, the median diameter of GS ranged between 300-1210 μm, the percentage of mass with particle size distribution < 200 μm at a height of 150 cm within Zier-A and Zier-O accounted for as low as 0.04%-0.05%, and showed good settling performance. The suspended solids in effluent can be maintained at 50-80 mg/L. Overall, the unique structural setting and control method of the Zier process provide another approach for the application of continuous AGS treatment for municipal sewage.
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Affiliation(s)
- Cong Wang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China; Beijing Drainage Group Co., Ltd., Beijing 100044, China
| | - Wei-Kang Qi
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Shu-Jun Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China; Beijing Drainage Group Co., Ltd., Beijing 100044, China
| | - Li-Fang Liu
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Yong-Zhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China.
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6
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Bai X, Hazi F, Takacs I, Wadhawan T, Parker WJ. A comprehensive floc model for simulating simultaneous nitrification, denitrification, and phosphorus removal. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 927:172023. [PMID: 38547982 DOI: 10.1016/j.scitotenv.2024.172023] [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: 01/31/2024] [Revised: 03/21/2024] [Accepted: 03/25/2024] [Indexed: 04/13/2024]
Abstract
A comprehensive floc model for simultaneous nitrification, denitrification, and phosphorus removal (SNDPR) was designed, incorporating polyphosphate-accumulating organisms (PAOs), glycogen-accumulating organisms (GAOs), intrinsic half-saturation coefficients, and explicit external mass transfer terms. The calibrated model was able to effectively describe experimental data over a range of operating conditions. The estimated intrinsic half-saturation coefficients of oxygen values for ammonia-oxidizing bacteria, nitrite-oxidizing bacteria, ordinary heterotrophic organisms (OHOs), PAOs, and GAOs were set at 0.08, 0.18, 0.03, 0.07, and 0.1 mg/L, respectively. Simulation suggested that low dissolved oxygen (DO) environments favor K-strategist nitrifying bacteria and PAOs. In SNDPR, virtually all influent and fermentation-generated volatile fatty acids were assimilated as polyhydroxyalkanoates by PAOs in the anaerobic phase. In the aerobic phase, PAOs absorbed 997 % and 171 % of the benchmark influent total phosphorus mass loading through aerobic growth and denitrification via nitrite. These high percentages were because they were calculated relative to the influent total phosphorus, rather than total phosphorus at the end of the anaerobic period. When considering simultaneous nitrification and denitrification, about 23.1 % of influent total Kjeldahl nitrogen was eliminated through denitrification by PAOs and OHOs via nitrite, which reduced the need for both oxygen and carbon in nitrogen removal. Moreover, the microbial and DO profiles within the floc indicated a distinct stratification, with decreasing DO and OHOs, and increasing PAOs towards the inner layer. This study demonstrates a successful floc model that can be used to investigate and design SNDPR for scientific and practical purposes.
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Affiliation(s)
- Xuanye Bai
- Department of Civil and Environmental Engineering, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada; Water Digital Solutions, Hatch Ltd, 2800 Speakman Dr, Mississauga, Ontario L5K 2R7, Canada.
| | - Ferenc Hazi
- Dynamita SARL, 2015 route d'Aiglun, 06910 Sigale, France
| | - Imre Takacs
- Dynamita SARL, 2015 route d'Aiglun, 06910 Sigale, France
| | | | - Wayne J Parker
- Department of Civil and Environmental Engineering, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada
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Yang J, Qian M, Wu S, Liao H, Yu F, Zou J, Li J. Insight into the role of chitosan in rapid recovery and re-stabilization of disintegrated aerobic granular sludge. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 356:120613. [PMID: 38547824 DOI: 10.1016/j.jenvman.2024.120613] [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: 11/03/2023] [Revised: 02/16/2024] [Accepted: 03/10/2024] [Indexed: 04/07/2024]
Abstract
The disintegration and instability of aerobic granular sludge (AGS) systems during long-term operation pose significant challenges to its practical implementation, and rapid recovery strategies for disintegrated AGS are gaining more attention. In this study, the recovery and re-stabilization of disintegrated AGS was investigated by adding chitosan to a sequencing batch reactor and simultaneously adjusting the pH to slightly acidic condition. Within 7 days, chitosan addition under slight acidity led to the re-aggregation of disintegrated granules, increasing the average particle size from 166.4 μm to 485.9 μm. Notably, sludge volume indexes at 5 min (SVI5) and 30 min (SVI30) decreased remarkably from 404.6 mL/g and 215.1 mL/g (SVI30/SVI5 = 0.53) to 49.1 mL/g and 47.6 mL/g (SVI30/SVI5 = 0.97), respectively. Subsequent operation for 43 days successfully re-stabilized previous collapsed AGS system, resulting in an average particle size of 750.2 μm. These mature and re-stabilized granules exhibited characteristics of large particle size, excellent settleability, compact structure, and high biomass retention. Furthermore, chitosan facilitated the recovery of COD and nitrogen removal performances within 17-23 days of operation. It effectively facilitated the rapid aggregation of disintegrated granules by charge neutralization and bridging effects under a slightly acidic environment. Moreover, the precipitated chitosan acted as carriers, promoting the adhesion of microorganisms once pH control was discontinued. The results of batch tests and microbial community analysis confirmed that chitosan addition increased sludge retention time, enriching slow-growing microorganisms and enhancing the stability and pollutant removal efficiency of the AGS system.
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Affiliation(s)
- Jiaqi Yang
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Mengjie Qian
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Shuyun Wu
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Hanglei Liao
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Fengfan Yu
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Jinte Zou
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou, 310014, China; Shaoxing Research Institute, Zhejiang University of Technology, Shaoxing, 312000, China.
| | - Jun Li
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou, 310014, China
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8
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Feng W, Zhang Q, Li J, Duan C, Peng Y. Novel anammox granules formation from conventional activated sludge for municipal wastewater treatment through flocs management. BIORESOURCE TECHNOLOGY 2024; 396:130384. [PMID: 38281548 DOI: 10.1016/j.biortech.2024.130384] [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: 11/14/2023] [Revised: 01/22/2024] [Accepted: 01/23/2024] [Indexed: 01/30/2024]
Abstract
The direct integration of anammox process into municipal wastewater treatment has caused widespread concern, but the lack of anammox seeds limited its real application. This study successfully cultivated anammox granules (322.0 μm) from conventional activated sludge treating municipal wastewater. Through ultra-low floc sludge retention times of 8d, nitrifiers on flocs were eliminated and partial nitrification was realized. Furthermore, highly bacteria-enriched granules were initially formed, with Nitrosomonas and Ca. Competibacter 4-fold higher than that of flocs. Specific staining results revealed the microbial interaction with Ca. Brocadia, considering that Ca. Competibacter and Nitrosomonas correspondingly identified in the inner and outer layers of granules. The percentage of Ca. Brocadia present on the granules increased substantially from 0.0 % to 3.0 %, accompanied by a nitrogen removal rate of 0.3 kg·m-3·d-1. Our findings revealed a valuable reference for the anammox bacteria in-situ enrichment under mainstream conditions, which provides theoretical guidance for anammox-based processes practical application.
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Affiliation(s)
- Wanyi Feng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Qiong Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Jialin Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Chenxue Duan
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China.
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9
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Liu Y, Liu Y, Zhao T, He Y, Zhu T, Chai H, Peng L. Smaller Aerobic Granules Significantly Reduce N 2O Production by Ammonia-Oxidizing Bacteria: Evidences from Biochemical and Isotopic Analyses. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:545-556. [PMID: 38111342 DOI: 10.1021/acs.est.3c06246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2023]
Abstract
The mitigation of nitrous oxide (N2O) is of primary significance to offset carbon footprints in aerobic granular sludge (AGS) systems. However, a significant knowledge gap still exists regarding the N2O production mechanism and its pathway contribution. To address this issue, the impact of varying granule sizes, dissolved oxygen (DO), and nitrite (NO2-) levels on N2O production by ammonia-oxidizing bacteria (AOB) during nitrification in AGS systems was comprehensively investigated. Biochemical and isotopic experiments revealed that increasing DO or decreasing NO2- levels reduced N2O emission factors (by 13.8 or 19.5%) and production rates (by 0.08 or 0.35 mg/g VSS/h) via weakening the role of the AOB denitrification pathway since increasing DO competed for more electrons required for AOB denitrification. Smaller granules (0.5 mm) preferred to diminish N2O production via enhancing the role of NH2OH pathway (i.e., 59.4-100% in the absence of NO2-), while larger granules (2.0 mm) induced conspicuously higher N2O production via the AOB denitrification pathway (approximately 100% at higher NO2- levels). Nitrifying AGS systems with a unified size of 0.5 mm achieved 42% N2O footprint reduction compared with the system with mixed sizes (0.5-2.0 mm) under optimal conditions (DO = 3.0 mg-O2/L and NO2- = 0 mg-N/L).
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Affiliation(s)
- Yiwen Liu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Yingrui Liu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Tianhang Zhao
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Yanying He
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Tingting Zhu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Hongxiang Chai
- Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Lai Peng
- Hubei Key Laboratory of Mineral Resources Processing and Environment, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070, China
- School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070, China
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10
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Asghar S, Chen L, He BB. Optimization of Simultaneous Nutrients and Chemical Oxygen Demand Removal from Anaerobically Digested Liquid Dairy Manure in a Two-Step Fed Sequencing Batch Reactor System Using Taguchi Method and Grey Relational Analysis. Appl Biochem Biotechnol 2024; 196:537-557. [PMID: 37155003 DOI: 10.1007/s12010-023-04562-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/26/2023] [Indexed: 05/10/2023]
Abstract
The technological development for efficient nutrient removal from liquid dairy manure is critical to a sustainable dairy industry. A nutrient removal process using a two-step fed sequencing batch reactor (SBR) system was developed in this study to achieve the applicability of simultaneous removal of phosphorus, nitrogen, and chemical oxygen demand from anaerobically digested liquid dairy manure (ADLDM). Three operating parameters, namely anaerobic time:aerobic time (min), anaerobic DO:aerobic DO (mg L-1), and hydraulic retention time (days), were systematically investigated and optimized using the Taguchi method and grey relational analysis for maximum removal efficiencies of total phosphorus (TP), ortho-phosphate (OP), ammonia-nitrogen (NH3-N), total nitrogen (TN), and chemical oxygen demand (COD) simultaneously. The results demonstrated that the optimal mean removal efficiencies of 91.21%, 92.63%, 91.82%, 88.61%, and 90.21% were achieved for TP, OP, NH3-N, TN, and COD at operating conditions, i.e., anaerobic:aerobic time of 90:90 min, anaerobic DO:aerobic DO of 0.4:2.4 mg L-1, and HRT of 3 days. Based on analysis of variance, the percentage contributions of these operating parameters towards the mean removal efficiencies of TP and COD were ranked in the order of anaerobic DO:aerobic DO > HRT > anaerobic time:aerobic time, while HRT was the most influential parameter for the mean removal efficiencies of OP, NH3-N, and TN followed by anaerobic time:aerobic time and anaerobic DO:aerobic DO. The optimal conditions obtained in this study are beneficial to the development of pilot and full-scale systems for simultaneous biological removal of phosphorus, nitrogen, and COD from ADLDM.
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Affiliation(s)
- Sehrish Asghar
- Environmental Science Program, College of Natural Resources, University of Idaho, Moscow, ID, 83843, USA
| | - Lide Chen
- Department of Soil and Water Systems, Twin Falls Research and Extension Center, University of Idaho, 315 Falls Avenue, PO Box 1827, Twin Falls, ID, 83303-1827, USA.
| | - B Brian He
- Department of Chemical and Biological Engineering, College of Engineering, University of Idaho, 875 Perimeter Dr. MS 0904, Moscow, ID, 83844, USA
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11
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Huang Y, Zhang J, Liu J, Gao X, Wang X. Effect of C/N on the microbial interactions of aerobic granular sludge system. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 349:119505. [PMID: 37992659 DOI: 10.1016/j.jenvman.2023.119505] [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: 04/01/2023] [Revised: 10/25/2023] [Accepted: 10/27/2023] [Indexed: 11/24/2023]
Abstract
The main focus of this study was to evaluate the operational stability and changes in microbial interactions of aerobic granular sludge (AGS) systems at reduced C/N (16, 8 and 4). The results showed that the removal efficiency of total nitrogen and total phosphorus decreased from 95.99 ± 0.93% and 84.44 ± 0.67% to 48.46 ± 1.92% and 50.93 ± 2.67%, respectively, when C/N was reduced from 16 to 4. The granule settling performance and stability also deteriorated. Molecular ecological network analysis showed that the reduction of the C/N ratio made the overall network as well as the subnetworks of the Proteobacteria and Bacteroidota more complex and tightly connected. Similarly, the subnetworks of two dominant genera (Thiothrix and Defluviicoccus) became more complex as the C/N decreased. Meanwhile, the decreased C/N ratio might promote competition among microbes in these overall networks and subnetworks. In conclusion, reduced C/N added complexity and tightness to microbial linkages within the AGS system, while increased competition between species might have contributed to the deterioration in pollutant removal performance. This study adds a new dimension to our understanding of the effects of C/N on the microbial community of AGS using a molecular ecological network approach.
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Affiliation(s)
- Yan Huang
- Beijing Engineering Research Center of Environmental Material for Water Purification, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Junqi Zhang
- Beijing Engineering Research Center of Environmental Material for Water Purification, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Junyu Liu
- Beijing Engineering Research Center of Environmental Material for Water Purification, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Xiaoping Gao
- Fuzhou Planning Design Research Institute, Fuzhou, 350108, China.
| | - Xiaohui Wang
- Beijing Engineering Research Center of Environmental Material for Water Purification, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing, 100029, China.
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12
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Insel G, Yilmaz G, Hazi F, Artan N. Model-based evaluation of simultaneous nitrification and denitrification in aerobic granular sludge systems. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:124780-124789. [PMID: 36645591 DOI: 10.1007/s11356-023-25252-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 01/07/2023] [Indexed: 01/17/2023]
Abstract
A lab-scale granular sludge sequencing batch reactor (G-SBR) system was operated using synthetic wastewater. The total nitrogen removal efficiency of 85% was obtained together with the achievement of complete total phosphorus removal with average granule diameter of 400 µm. Dual-step nitrification and denitrification model with fixed biofilm thickness was used for performance analysis. The denitrification mode only contributed to TN removal with 25% which can be calculated with process stoichiometry. The remaining nitrogen removal could be explained by simulating simultaneous nitrification and denitrification which was responsible for 75% denitrification during aerobic period. In addition, low NO3- concentration at the beginning of the fill period provided advantage for securing a prolonged anaerobic period for enhanced biological phosphorus removal (EBPR). The model parameters of boundary layer thickness (zBL = 50 µm) and half-saturation of O2 for nitrite-oxidizing bacteria (KO2,NOB = 0.5 gO2/m3) were tuned to fit NO2 and NO3 profiles in SBR cycle.
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Affiliation(s)
- Güçlü Insel
- Environmental Engineering Department, Istanbul Technical University, Maslak, Istanbul, Turkey
| | - Gulsum Yilmaz
- Environmental Engineering Department, Istanbul University-Cerrahpasa, Avcilar, Istanbul, Turkey.
| | - Ferenc Hazi
- Dynamita, 2015 Route d'Aiglun, Sigale, France
| | - Nazik Artan
- Environmental Engineering Department, Istanbul Technical University, Maslak, Istanbul, Turkey
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13
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Miyake M, Hasebe Y, Furusawa K, Shiomi H, Inoue D, Ike M. Enhancement of nutrient removal in an activated sludge process using aerobic granular sludge augmentation strategy with ammonium-based aeration control. CHEMOSPHERE 2023; 340:139826. [PMID: 37586487 DOI: 10.1016/j.chemosphere.2023.139826] [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: 02/17/2023] [Revised: 07/18/2023] [Accepted: 08/12/2023] [Indexed: 08/18/2023]
Abstract
To enhance nutrient removal from low-strength municipal wastewater in a continuous-flow activated sludge (CFAS) process using aerobic granular sludge (AGS) augmentation strategy, a pilot-scale demonstration was configured with a mainstream reactor (anaerobic/aerobic process) and a sidestream sequencing batch reactor for AGS production. The aeration of the mainstream reactor was controlled based on dissolved oxygen (DO) and ammonium concentrations during Phases I and II-III, respectively. During Phase III, an anoxic zone was created in the mainstream aerobic tank. Throughout the demonstration period, excellent sludge settleability in the mainstream reactor (SVI30 ≤ 80 mL g-1) under long sludge retention time conditions (≥12 d) allowed the maintenance of a high mixed liquor suspended solids concentration (≥3000 mg L-1). The total nitrogen (TN) removal ratio improved significantly during Phases II and III (49.3 ± 4.1% and 50.1 ± 10.2%, respectively) compared to Phase I (43.2 ± 5.5%). Low DO concentration (< 0.5 mg L-1) by the ammonium-based aeration tended to increase the simultaneous nitrification and denitrification efficiency (> 40%), enhancing TN removal (> 50%). The reduction of DO and nitrate concentrations in the returning sludge liquor can stabilize phosphorus removal (approximately 80% of the 25th percentile). In addition, the aeration efficiency during Phase III decreased by 26-29% compared to Phase I. These results suggest that the introduction of ammonium-based aeration control to the CFAS using the AGS augmentation strategy could contribute to superior sewerage treatment, including nutrient removal and a low carbon footprint.
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Affiliation(s)
- Masaki Miyake
- R&D Center, Organo Corporation, 4-4-1 Nishionuma, Minami-ku, Sagamihara, Kanagawa 252-0332, Japan; Division of Sustainable Energy and Environmental Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Yoshiaki Hasebe
- R&D Center, Organo Corporation, 4-4-1 Nishionuma, Minami-ku, Sagamihara, Kanagawa 252-0332, Japan
| | - Kazuki Furusawa
- Bureau of Sewerage, Tokyo Metropolitan Government, 2-8-1 Nishishinjuku, Shinjuku-ku, Tokyo 163-8001, Japan
| | - Hiroshi Shiomi
- Bureau of Sewerage, Tokyo Metropolitan Government, 2-8-1 Nishishinjuku, Shinjuku-ku, Tokyo 163-8001, Japan
| | - Daisuke Inoue
- Division of Sustainable Energy and Environmental Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Michihiko Ike
- Division of Sustainable Energy and Environmental Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
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14
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Jin Y, Ding J, Zhan W, Du J, Wang G, Pang J, Ren N, Yang S. Effect of dissolved oxygen concentration on performance and mechanism of simultaneous nitrification and denitrification in integrated fixed-film activated sludge sequencing batch reactors. BIORESOURCE TECHNOLOGY 2023; 387:129616. [PMID: 37544541 DOI: 10.1016/j.biortech.2023.129616] [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: 06/11/2023] [Revised: 07/30/2023] [Accepted: 08/01/2023] [Indexed: 08/08/2023]
Abstract
Integrated fixed-film activated sludge (IFAS) is a superior system for achieving simultaneous nitrification and denitrification (SND), however, the impact of dissolved oxygen (DO) has not been fully elucidated. Therefore, this study investigated the effect of DO concentration on performance and mechanism of SND in IFAS system. Results showed that IFAS outperformed control systems and achieved optimal SND performance at a DO concentration of 0.5 mg/L, with an SND efficiency of 88.51% and total nitrogen removal efficiency of 82.78%. Typical cycles analysis demonstrated limited-DO promoted SND performance. Further analysis implied biofilms exhibited high biomass and denitrification activity with decreasing DO. Microbial community analysis revealed low DO concentrations were responsible for abundant functional groups and genes associated with SND and promoted unconventional nitrogen removal pathways. Moreover, co-occurrence network analysis elucidated microbial interactions, responses to DO, and keystone genera. This study helps understanding the roles of DO for enhanced SND in IFAS.
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Affiliation(s)
- Yaruo Jin
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Jie Ding
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Wei Zhan
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Juanshan Du
- KENTECH Institute of Environmental & Climate Technology, Korea Institute of Energy Technology (KENTECH), Naju 58330, South Korea
| | - Guangyuan Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Jiwei Pang
- China Energy Conservation and Environmental Protection Group, Beijing 100089, China
| | - Nanqi Ren
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Shanshan Yang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China.
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15
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Huang S, Fu Y, Zhang H, Wang C, Zou C, Lu X. Research progress of novel bio-denitrification technology in deep wastewater treatment. Front Microbiol 2023; 14:1284369. [PMID: 37860138 PMCID: PMC10582329 DOI: 10.3389/fmicb.2023.1284369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Accepted: 09/20/2023] [Indexed: 10/21/2023] Open
Abstract
Excessive nitrogen emissions are a major contributor to water pollution, posing a threat not only to the environment but also to human health. Therefore, achieving deep denitrification of wastewater is of significant importance. Traditional biological denitrification methods have some drawbacks, including long processing times, substantial land requirements, high energy consumption, and high investment and operational costs. In contrast, the novel bio-denitrification technology reduces the traditional processing time and lowers operational and maintenance costs while improving denitrification efficiency. This technology falls within the category of environmentally friendly, low-energy deep denitrification methods. This paper introduces several innovative bio-denitrification technologies and their combinations, conducts a comparative analysis of their denitrification efficiency across various wastewater types, and concludes by outlining the future prospects for the development of these novel bio-denitrification technologies.
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Affiliation(s)
| | | | | | | | | | - Xiuguo Lu
- School of Civil Engineering and Architecture, East China Jiao Tong University, Nanchang, China
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16
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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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17
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Song X, Zhang G, Luan J, Liu G, Wang J. Effect of magnetic fields on simultaneous nitrification and denitrification microbial systems. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2023; 88:517-529. [PMID: 37578871 PMCID: wst_2023_250 DOI: 10.2166/wst.2023.250] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/16/2023]
Abstract
Magnetic fields positively influence the nitrogen removal efficiency in activated sludge systems. However, the structural succession pattern of microorganisms by magnetic fields still remains further explored. In this paper, a magnetic simultaneous nitrification and denitrification (MSND) reactor was constructed, and the influence of optimized magnetic field intensity (0, 10, 20 and 30 mT) on the nitrogen removal efficiency was investigated at HRT 6 h, 28.0-30.0 °C, and pH 7.0-8.0. Molecular biology was used to investigate the succession process of the dominant microbial flora and the functional gene structure of MSND systems. The results showed that the denitrification effects of the MSND system were significantly enhanced, which contributed to the lower concentration of total nitrogen in the effluent of the magnetic reactor than that of the nonmagnetic group reactor. The magnetic fields induced the succession of microbial community structure and improved the stability of microbial communities, thereby the relative abundances of nitrifying and denitrifying bacteria, and the functional genes were improved. In particular, the abundance of functional genes related to gene proliferation and transmembrane transport was increased. Therefore, the efficient nitrogen removal was achieved, which gives inspiration in the enhanced wastewater treatment by magnetic fields.
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Affiliation(s)
- Xintong Song
- School of Civil Engineering and Architecture, University of Jinan, Jinan 250022, China E-mail:
| | - Guanglu Zhang
- Jinan Urban Construction Group Co., Ltd, Jinan 250014, China
| | - Jiajia Luan
- Logistics Service Office of Weifang Vocational College, Weifang 262737, China
| | - Guicai Liu
- School of Civil Engineering and Architecture, University of Jinan, Jinan 250022, China
| | - Jiabin Wang
- School of Civil Engineering and Architecture, University of Jinan, Jinan 250022, China
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18
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Ekholm J, de Blois M, Persson F, Gustavsson DJI, Bengtsson S, van Erp T, Wilén BM. Case study of aerobic granular sludge and activated sludge-Energy usage, footprint, and nutrient removal. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2023; 95:e10914. [PMID: 37494966 DOI: 10.1002/wer.10914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 06/29/2023] [Accepted: 07/23/2023] [Indexed: 07/28/2023]
Abstract
This study demonstrates a comparison of energy usage, land footprint, and volumetric requirements of municipal wastewater treatment with aerobic granular sludge (AGS) and conventional activated sludge (CAS) at a full-scale wastewater treatment plant characterized by large fluctuations in nutrient loadings and temperature. The concentration of organic matter in the influent to the AGS was increased by means of hydrolysis and bypassing the pre-settler. Both treatment lines produced effluent concentrations below 5 mg BOD7 L-1 , 10 mg TN L-1 , and 1 mg TP L-1 , by enhanced biological nitrogen- and phosphorus removal. In this case study, the averages of volumetric energy usage over 1 year were 0.22 ± 0.08 and 0.26 ± 0.07 kWh m-3 for the AGS and CAS, respectively. A larger difference was observed for the energy usage per reduced population equivalents (P.E.), which was on average 0.19 ± 0.08 kWh P.E.-1 for the AGS and 0.30 ± 0.08 kWh P.E.-1 for the CAS. However, both processes had the potential for decreased energy usage. Over 1 year, both processes showed similar fluctuations in energy usage, related to variations in loading, temperature, and DO. The AGS had a lower specific area, 0.3 m2 m-3 d-1 , compared to 0.6 m2 m-3 d-1 of the CAS, and also a lower specific volume, 1.3 m3 m-3 d-1 compared to 2.0 m3 m-3 d-1 . This study confirms that AGS at full-scale can be compact and still have comparable energy usage as CAS. PRACTITIONER POINTS: Full-scale case study comparison of aerobic granular sludge (AGS) and conventional activated sludge (CAS), operated in parallel. AGS had 50 % lower footprint compared to CAS. Energy usage was lower in the AGS, but both processes had potential to improve the energy usage efficiency. Both processes showed low average effluent concentrations.
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Affiliation(s)
- Jennifer Ekholm
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | | | - Frank Persson
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | | | | | | | - Britt-Marie Wilén
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden
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19
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Cui H, Zhang L, Zhang Q, Li X, Peng Y, Wang C. Enhancing nitrogen removal of carbon-limited municipal wastewater in step-feed biofilm batch reactor through integration of anammox. BIORESOURCE TECHNOLOGY 2023; 381:129091. [PMID: 37105262 DOI: 10.1016/j.biortech.2023.129091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 04/07/2023] [Accepted: 04/22/2023] [Indexed: 05/09/2023]
Abstract
The biological nitrogen removal of municipal wastewater was successfully improved by integrating anammox in a step-feed sequencing biofilm batch reactor. Despite fluctuating influent carbon to nitrogen ratio (1.9-5.1) and decreasing temperature (24.1-16.3 ℃), nitrogen removal efficiency of 95.9 ± 1.4 % and nitrogen removal rate of 0.23 ± 0.02 kg N/(m3·d) were successfully maintained without requirement of external carbon sources. The advanced removal performance was mainly attributed to the enhanced anammox. Anammox bacteria presented a high relative abundance (42.9% in biofilms, 1.5% in flocs) and anammox activity was as high as 5.42 ± 0.12 mg N/(g volatile suspended solids·h). Further analysis suggested that flexible control of influent organic and ammonium through step-feeding could provide multiple substrate supply for anammox reaction, potentially resulting in stable combination of anammox with hybrid-nitrite-shunt processes. Overall, this study provides a promising anammox-related application with simple-control step-feed strategy for enhanced and stable nitrogen removal from carbon-limited municipal wastewater.
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Affiliation(s)
- Huihui Cui
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Liang Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Qiong Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Xiyao Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China.
| | - Chuanxin Wang
- Guangdong Shouhui Lantian Engineering and Technology Co., Ltd., Units 01 and 04, 5/F, Xingguang Yingjing Commercial Center, 117 Shuiyin Road, Yuexiu District, Guangzhou, PR China
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20
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James SN, Vijayanandan A. Recent advances in simultaneous nitrification and denitrification for nitrogen and micropollutant removal: a review. Biodegradation 2023; 34:103-123. [PMID: 36899211 DOI: 10.1007/s10532-023-10015-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Accepted: 02/06/2023] [Indexed: 03/12/2023]
Abstract
Simultaneous Nitrification and Denitrification (SND) is a promising process for biological nitrogen removal. Compared to conventional nitrogen removal processes, SND is cost-effective due to the decreased structural footprint and low oxygen and energy requirements. This critical review summarizes the current knowledge on SND related to fundamentals, mechanisms, and influence factors. The creation of stable aerobic and anoxic conditions within the flocs, as well as the optimization of dissolved oxygen (DO), are the most significant challenges in SND. Innovative reactor configurations coupled with diversified microbial communities have achieved significant carbon and nitrogen reduction from wastewater. In addition, the review also presents the recent advances in SND for removing micropollutants. The micropollutants are exposed to various enzymes due to the microaerobic and diverse redox conditions present in the SND system, which would eventually enhance biotransformation. This review presents SND as a potential biological treatment process for carbon, nitrogen, and micropollutant removal from wastewater.
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Affiliation(s)
- Susan N James
- Department of Civil Engineering, Indian Institute of Technology, Delhi, 110016, India
| | - Arya Vijayanandan
- Department of Civil Engineering, Indian Institute of Technology, Delhi, 110016, India.
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21
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Zhao W, Bi X, Bai M, Wang Y. Research advances of ammonia oxidation microorganisms in wastewater: metabolic characteristics, microbial community, influencing factors and process applications. Bioprocess Biosyst Eng 2023; 46:621-633. [PMID: 36988685 DOI: 10.1007/s00449-023-02866-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Accepted: 03/21/2023] [Indexed: 03/30/2023]
Abstract
Ammonia oxidation carried out by ammonia-oxidizing microorganisms (AOMs) is a central step in the global nitrogen cycle. Aerobic AOMs comprise conventional ammonia-oxidizing bacteria (AOB), novel ammonia-oxidizing archaea (AOA), which could exist in complex and extreme conditions, and complete ammonia oxidizers (comammox), which directly oxidize ammonia to nitrate within a single cell. Anaerobic AOMs mainly comprise anaerobic ammonia-oxidizing bacteria (AnAOB), which can transform NH4+-N and NO2--N into N2 under anaerobic conditions. In this review, the unique metabolic characteristics, microbial community of AOMs and the influencing factors are discussed. Process applications of nitrification/denitrification, nitritation/denitrification, nitritation/anammox and partial denitrification/anammox in wastewater treatment systems are emphasized. The future development of nitrogen removal processes using AOMs is expected, enrichment of comammox facilitates the complete nitrification performance, inhibiting the activity of comammox and NOB could achieve stable nitritation, and additionally, AnAOB conducting the anammox process in municipal wastewater is a promising development direction.
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Affiliation(s)
- Weihua Zhao
- State and Local Joint Engineering Research Center of Municipal Wastewater Treatment and Resource Recycling, Qingdao University of Technology, Qingdao, 266033, People's Republic of China.
- School of Marine Science and Technology, Harbin Institute of Technology, Weihai, 264209, People's Republic of China.
- Qingdao University of Technology, Huangdao District, Qingdao, 266525, People's Republic of China.
| | - Xuejun Bi
- State and Local Joint Engineering Research Center of Municipal Wastewater Treatment and Resource Recycling, Qingdao University of Technology, Qingdao, 266033, People's Republic of China
| | - Meng Bai
- State and Local Joint Engineering Research Center of Municipal Wastewater Treatment and Resource Recycling, Qingdao University of Technology, Qingdao, 266033, People's Republic of China
| | - Yanyan Wang
- State and Local Joint Engineering Research Center of Municipal Wastewater Treatment and Resource Recycling, Qingdao University of Technology, Qingdao, 266033, People's Republic of China
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22
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Cavanaugh SK, Nguyen Quoc B, Jacobson E, Bucher R, Sukapanpotharam P, Winkler MKH. Impact of nitrite and oxygen on nitrous oxide emissions from a granular sludge sequencing batch reactor. CHEMOSPHERE 2022; 308:136378. [PMID: 36113651 DOI: 10.1016/j.chemosphere.2022.136378] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 09/03/2022] [Accepted: 09/05/2022] [Indexed: 06/15/2023]
Abstract
Maximizing nutrient removal and minimizing greenhouse gas (GHG) emissions is imperative for the future of wastewater treatment. As municipalities focus on minimizing their carbon footprints, future permits could regulate GHG emissions from wastewater treatment plants. This study investigates how nitrous oxide (N2O) emissions are affected by dissolved oxygen and nitrite concentrations, providing potential strategies to meet possible gaseous emission permits. A lab-scale sequencing batch reactor (SBR) was enriched with aerobic granular sludge (AGS) capable of phosphate removal and simultaneous nitrification-denitrification (SND). N2O emissions were tracked at varying dissolved oxygen (DO) and nitrite (NO2-) concentrations, with >99% SND efficiency and 93%-100% phosphate removal efficiency. Higher DO and NO2- concentrations were associated with higher N2O emissions. Emissions were minimized at a DO concentration of 1 mg L-1, with an average emission factor of 0.18% of oxidized NH3-N emitted as N2O-N, which is lower than factors from many full-scale treatment plants (Vasilaki et al., 2019) and similar to a Nereda® full-scale AGS SBR (van Dijk et al., 2021). This challenges assertions that AGS emits more N2O than conventional activated sludge, although more research at full-scale with influent quality variations is required to confirm this trend. Molecular analyses revealed that the efficient SND was likely achieved with shortcut nitrogen removal facilitated by a low presence of nitrite oxidizing bacteria and a large population of denitrifying phosphate accumulating organisms, which far outnumbered denitrifying glycogen accumulating organisms.
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Affiliation(s)
- Shannon K Cavanaugh
- University of Washington, Department of Civil & Environmental Engineering, Seattle, WA, 98195, USA.
| | - Bao Nguyen Quoc
- University of Washington, Department of Civil & Environmental Engineering, Seattle, WA, 98195, USA
| | - Eron Jacobson
- Resource Recovery, Wastewater Treatment Division, King County Department of Natural Resources and Parks, Seattle, WA, 98104, USA
| | - Robert Bucher
- Resource Recovery, Wastewater Treatment Division, King County Department of Natural Resources and Parks, Seattle, WA, 98104, USA
| | - Pardi Sukapanpotharam
- Resource Recovery, Wastewater Treatment Division, King County Department of Natural Resources and Parks, Seattle, WA, 98104, USA
| | - Mari-Karoliina H Winkler
- University of Washington, Department of Civil & Environmental Engineering, Seattle, WA, 98195, USA
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23
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Gemza N, Janiak K, Zięba B, Przyszlak J, Kuśnierz M. Long-term effects of hydrocyclone operation on activated sludge morphology and full-scale secondary settling tank wet-weather operation in long sludge age WWTP. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 845:157224. [PMID: 35835188 DOI: 10.1016/j.scitotenv.2022.157224] [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: 04/21/2022] [Revised: 06/30/2022] [Accepted: 07/04/2022] [Indexed: 06/15/2023]
Abstract
This paper presents the study concerning long-term effects of a full scale hydrocyclone unit implemented in a continuous flow long sludge age system, on sedimentation, treatment efficiency and sludge morphology. The research concentrates on identifying the mechanisms of sludge behaviour within the system. The gravimetric selection of activated sludge via a hydrocyclone is a recent development for enhancing sludge separation, where heavier flocs are retained in the system, and lighter ones are discarded as waste sludge. The effects of implementing hydroclyclones were analysed with the use of SEM imagining and fractal dimensioning through the frequent assessment of sludge settling capabilities, effluent quality, and floc properties. Over the course of 60 weeks of hydrocyclone operation, sedimentation efficiency varied significantly. Sludge volume index values of 40 mL/g, achieved during the warm season, were not sustained when the temperature decreased and an overgrowth of filamentous bacteria occurred. Good settling efficiency was also observed in batch tests, where settling velocity of experimental sludge was app. 1 m/h higher than for the reference train at the same concentrations. This was confirmed during wet weather, as the experimental train sustained safe sludge blanket height in secondary clarifiers. SEM imaging and fractal dimension analysis revealed that the underflow that returned to the system had a more compact and spherical shape, which led to an increased content of granule-like particles in the reactor. The presence of flocs with a diameter exceeding 900 μm in the underflow, which is not observed in the feed, indicated agglomeration within the hydrocyclone. This is contradictory to most of the literature data coming from laboratory experiments. This phenomenon was attributed to differences in the size and geometry of the used hydrocyclones, and the potential process mechanism was presented.
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Affiliation(s)
- Natalia Gemza
- Faculty of Environmental Engineering, Wroclaw University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wroclaw, Poland; Wroclaw Municipal Water and Sewage Company, Na Grobli 19, 50-421 Wroclaw, Poland.
| | - Kamil Janiak
- Faculty of Environmental Engineering, Wroclaw University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wroclaw, Poland; Wroclaw Municipal Water and Sewage Company, Na Grobli 19, 50-421 Wroclaw, Poland
| | - Bartosz Zięba
- Faculty of Environmental Engineering, Wroclaw University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wroclaw, Poland
| | - Jacek Przyszlak
- Wroclaw Municipal Water and Sewage Company, Na Grobli 19, 50-421 Wroclaw, Poland
| | - Magdalena Kuśnierz
- The Faculty of Environmental Engineering and Geodesy, Wroclaw University of Environmental and Life Sciences, Norwida 25, 50-375 Wroclaw, Poland
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24
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Zou X, Mohammed A, Gao M, Liu Y. Mature landfill leachate treatment using granular sludge-based reactor (GSR) via nitritation/denitritation: Process startup and optimization. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 844:157078. [PMID: 35787895 DOI: 10.1016/j.scitotenv.2022.157078] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 06/20/2022] [Accepted: 06/27/2022] [Indexed: 06/15/2023]
Abstract
Mature landfill leachate wastewater (LLW) was characterized by high ammonia, refractory chemical oxygen demand (COD) and heavy metal contents, which limits the nitrogen removal in conventional activated sludge systems. Granular sludge is known to be more resistant to toxic compounds because of its dense structure and diverse microbial community. Here, granular sludge-based reactor (GSR) was applied with nitritation/denitritation (Nit/DNit) process for effective ammonia-rich mature LLW treatment at 20 °C. After a short startup period, the efficiencies of ammonia removal and total inorganic nitrogen removal stabilized at 99 % and 93 %, respectively, under a hydraulic retention time (HRT) of 6 h. High ammonia oxidation rate (~ 0.64 g N/g VSS/d) was achieved, with ~93 % ammonia conversing to nitrite before being reduced to nitrogen gas. Microbial analysis results revealed that Nitrosomonas (ammonia oxidizing bacteria) and Thauera (denitrifiers) were the dominant bacteria with key functional genes involved in the Nit/DNit. With an increase in the LLW loading, increased ammonia oxidation rates and biomass retention were also observed. This study demonstrated that granular sludge-based technology is feasible for mature LLW treatment.
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Affiliation(s)
- Xin Zou
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Abdul Mohammed
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Mengjiao Gao
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Yang Liu
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada.
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25
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Alves OIM, Araújo JM, Silva PMJ, Magnus BS, Gavazza S, Florencio L, Kato MT. Formation and stability of aerobic granular sludge in a sequential batch reactor for the simultaneous removal of organic matter and nutrients from low-strength domestic wastewater. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 843:156988. [PMID: 35772566 DOI: 10.1016/j.scitotenv.2022.156988] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Revised: 06/13/2022] [Accepted: 06/22/2022] [Indexed: 06/15/2023]
Abstract
Simultaneous removal of organic matter, nitrogen, and phosphorus, via simultaneous nitrification and denitrification (SND) and enhanced biological phosphorus removal processes, was evaluated in a pilot-scale sequential batch reactor. The focus was on granule's morphology, stability, microbiological composition, and reactor performance while treating diluted domestic wastewater with total chemical oxygen demand (CODt) of ≈ 200 mg.L-1. The applied organic loading rate was 0.9 ± 0.3 kg CODt.m-3.d-1 in the experiment. Aerobic granular sludge developed gradually. After 87-day operation, granules (diameter ≥ 0.2 mm) were ≥ 50 % of the biomass, and after 168 days, complete granulation was obtained (≥ 80 % of biomass). In the third period (days 168-247, complete granulation), mixed liquor biomass reached a volatile suspended solids (VSS) concentration of 1.2 ± 0.3 g VSS.L-1, with the granules remaining stable until the experimental end. In this period, low effluent concentrations of COD, nitrogen (NH4+-N, NO2--N and NO3--N) and phosphate (PO43-P) were obtained (mg.L-1): 36 ± 11; 4 ± 5; 3 ± 3, 4 ± 5; and 0.9 ± 0.4, respectively. COD, NH4+-N, and PO43--P removal efficiencies (%) were 80 ± 11; 83 ± 20; and 55 ± 24, respectively. Heterotrophic nitrification and SND were observed, resulting in a process efficiency of 31 % even with dissolved oxygen applied to saturation. The phosphate removal was mainly attributed to denitrifying phosphorus accumulating organisms. Pseudomonas, the dominant genus found, acted in nitrogen and phosphorus removal. Pseudoxanthomonas also assisted in phosphorus removal. Bacterial communities in the flocs (≈ 20 % of biomass) during the last period were similar to those in the granules; therefore, they constituted the basis for granule formation, directly contributed to the simultaneous good removal of organic matter and nutrients.
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Affiliation(s)
- Oucilane I M Alves
- Department of Civil and Environmental Engineering, Federal University of Pernambuco, Recife, Pernambuco, Brazil
| | - Julliana M Araújo
- Department of Civil and Environmental Engineering, Federal University of Pernambuco, Recife, Pernambuco, Brazil; Federal Institute of Education, Science and Technology of Sertão Pernambucano, Campus Ouricuri, Estrada do Tamboril s/n, Zona Rural, Ouricuri, Pernambuco, Brazil
| | - Poliana M J Silva
- Department of Civil and Environmental Engineering, Federal University of Pernambuco, Recife, Pernambuco, Brazil
| | - Bruna S Magnus
- Department of Civil and Environmental Engineering, Federal University of Pernambuco, Recife, Pernambuco, Brazil.
| | - Sávia Gavazza
- Department of Civil and Environmental Engineering, Federal University of Pernambuco, Recife, Pernambuco, Brazil.
| | - Lourdinha Florencio
- Department of Civil and Environmental Engineering, Federal University of Pernambuco, Recife, Pernambuco, Brazil.
| | - Mario T Kato
- Department of Civil and Environmental Engineering, Federal University of Pernambuco, Recife, Pernambuco, Brazil.
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26
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Di Capua F, Iannacone F, Sabba F, Esposito G. Simultaneous nitrification-denitrification in biofilm systems for wastewater treatment: Key factors, potential routes, and engineered applications. BIORESOURCE TECHNOLOGY 2022; 361:127702. [PMID: 35905872 DOI: 10.1016/j.biortech.2022.127702] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 07/20/2022] [Accepted: 07/22/2022] [Indexed: 06/15/2023]
Abstract
Simultaneous nitrification-denitrification (SND) is an advantageous bioprocess that allows the complete removal of ammonia nitrogen through sequential redox reactions leading to nitrogen gas production. SND can govern nitrogen removal in single-stage biofilm systems, such as the moving bed biofilm reactor and aerobic granular sludge system, as oxygen gradients allow the development of multilayered biofilms including nitrifying and denitrifying bacteria. Environmental and operational conditions can strongly influence SND performance, biofilm development and biochemical pathways. Recent advances have outlined the possibility to reduce the carbon and energy consumption of the process via the "shortcut pathway", and simultaneously remove both N and phosphorus under specific operational conditions, opening new possibilities for wastewater treatment. This work critically reviews the factors influencing SND and its application in biofilm systems from laboratory to full scale. Operational strategies to enhance SND efficiency and hints to reduce nitrous oxide emission and operational costs are provided.
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Affiliation(s)
- Francesco Di Capua
- Department of Civil, Environmental, Land, Building Engineering and Chemistry, Polytechnic University of Bari, Bari 70125, Italy.
| | | | | | - Giovanni Esposito
- Department of Civil, Architectural and Environmental Engineering, University of Naples Federico II, Via Claudio 21, Naples 80125, Italy
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27
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Wang Y, Liang B, Kang F, Wang Y, Zhao C, Lyu Z, Zhu T, Zhang Z. An efficient anoxic/aerobic/aerobic/anoxic process for domestic sewage treatment: From feasibility to application. Front Microbiol 2022; 13:970548. [PMID: 35983333 PMCID: PMC9378819 DOI: 10.3389/fmicb.2022.970548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Accepted: 07/14/2022] [Indexed: 11/25/2022] Open
Abstract
In this paper, the anoxic/aerobic/aerobic/anoxic (AOOA) process was proposed using fixed biofilms in a continuous plug-flow multi-chamber reactor, and no sludge reflux operation was performed during the 190 days of operation. The reactor volume ratio of 1.5:2:1.5:1 (A/O/O/A) with the dissolved oxygen (DO) concentration of 2 mg L−1 in the aerobic zone was the optimal condition for reactor operation. According to the results obtained from the treatment of real domestic sewage, when the hydraulic retention time (HRT) was 6 h, the effluent of the reactor could meet the discharge standard even in cold conditions (13°C). Specifically, the elemental-sulfur-based autotrophic denitrification (ESAD) process contributed the most to the removal of total inorganic nitrogen (TIN) in the reactor. In addition, the use of vibration method was helpful in removing excess sludge from the biofilms of the reactor. Overall, the AOOA process is an efficient and convenient method for treating domestic sewage.
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28
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van den Berg L, Toja Ortega S, van Loosdrecht MC, de Kreuk MK. Diffusion of soluble organic substrates in aerobic granular sludge: Effect of molecular weight. WATER RESEARCH X 2022; 16:100148. [PMID: 35814501 PMCID: PMC9263526 DOI: 10.1016/j.wroa.2022.100148] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 05/17/2022] [Accepted: 06/30/2022] [Indexed: 06/15/2023]
Abstract
Aerobic granular sludge (AGS) is an advanced biofilm-based technology for wastewater treatment. Diffusion of substrates into the granules is a key aspect of this technology. Domestic wastewater contains soluble organic substrates of different sizes that could potentially diffuse into the granules. In this study, the relation between the molecular weight of a substrate and its diffusion coefficient within the granule was studied with model substrates (polyethylene glycols (PEGs) with a molecular weight between 62 and 10 000 Da). The diffusion coefficients of the model substrates within granules from a full-scale installation were measured with the 'transient uptake of a non-reactive solute' method. The diffusion coefficients in the granules were not significantly different from the diffusion coefficients in water, at least up to 4000 Da molecular weight. This indicates that these PEGs were not obstructed by the granule matrix. The 10 kDa PEG behaved differently from the lighter PEGs, as it could not penetrate the entire granule. Furthermore, the granule structure was characterized with Environmental Scanning Electron Microscopy (ESEM). The granules displayed an open structure with large macropores and semi-solid regions, which contained microbial cells. The diffusion results suggest that most diffusing molecules were unobstructed in the macropores and barely obstructed in the semi-solid regions. Only the diffusion of the 10 kDa PEG seemed to be hindered by the semi-solid regions, but not by the macropores. Lastly, the apparent molecular weight distribution of domestic wastewater soluble COD was determined with ultrafiltration membranes of 100, 10, and 1 kDa molecular weight cut-off. The influent fractionation revealed that a large part (61-69%) of the influent soluble COD was lighter than 1 kDa. As molecules lighter than 1 kDa diffuse easily, the majority of the influent soluble COD can be considered as diffusible COD. These findings provide new insight into the availability of influent COD for granular sludge.
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Affiliation(s)
- Lenno van den Berg
- Department of Water Management, Delft University of Technology, the Netherlands
| | - Sara Toja Ortega
- Department of Water Management, Delft University of Technology, the Netherlands
| | | | - Merle K. de Kreuk
- Department of Water Management, Delft University of Technology, the Netherlands
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29
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Toja Ortega S, van den Berg L, Pronk M, de Kreuk MK. Hydrolysis capacity of different sized granules in a full-scale aerobic granular sludge (AGS) reactor. WATER RESEARCH X 2022; 16:100151. [PMID: 35965888 PMCID: PMC9364025 DOI: 10.1016/j.wroa.2022.100151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 07/27/2022] [Accepted: 07/30/2022] [Indexed: 06/15/2023]
Abstract
In aerobic granular sludge (AGS) reactors, granules of different sizes coexist in a single reactor. Their differences in settling behaviour cause stratification in the settled granule bed. In combination with substrate concentration gradients over the reactor height during the anaerobic plug-flow feeding regime, this can result in functional differences between granule sizes. In this study, we compared the hydrolytic activity in granules of 4 size ranges (between 0.5 and 4.8 mm diameter) collected from a full-scale AGS installation. Protease and amylase activities were quantified through fluorescent activity assays. To visualise where the hydrolytic active zones were located within the granules, the hydrolysis sites were visualized microscopically after incubating intact and sliced granules with fluorescent casein and starch. The microbial community was studied using fluorescent in situ hybridization (FISH) and sequencing. The results of these assays indicated that hydrolytic capacity was present throughout the granules, but the hydrolysis of bulk substrates was restricted to the outer 100 µm, approximately. Many of the microorganisms studied by FISH, such as polyphosphate and glycogen accumulating organisms (PAO and GAO), were abundant in the vicinity of the hydrolytically active sites. The biomass-specific hydrolysis rate depended mainly on the available granule surface area, suggesting that different sized granules are not differentiated in terms of hydrolytic capacity. Thus, the substrate concentration gradients that are present during the anaerobic feeding in AGS reactors do not seem to affect hydrolytic activity at the granule surfaces. In this paper, we discuss the possible reasons for this and reflect about the implications for AGS technology.
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Key Words
- AGS, aerobic granular sludge
- AS, activated sludge
- Activity staining
- Aerobic granular sludge
- Biomass segregation
- COD, chemical oxygen demand
- EBPR, enhanced biological phosphorus removal
- EPS, extracellular polymeric substances
- FISH, fluorescence in situ hybridization
- GAO, glycogen-accumulating organism
- Hydrolysis
- PAO, polyphosphate-accumulating organism
- Polymeric substrates
- SBR, sequencing batch reactor
- SND, simultaneous nitrification-denitrification
- SRT, solids retention time
- TSS, total suspended solids
- VFA, volatile fatty acid
- VSS, volatile suspended solids
- WWTP, wastewater treatment plant
- Wastewater treatment
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Affiliation(s)
- Sara Toja Ortega
- Section Sanitary Engineering, Department of Water Management, Delft University of Technology, Stevinweg 1, Delft 2628CN, the Netherlands
| | - Lenno van den Berg
- Section Sanitary Engineering, Department of Water Management, Delft University of Technology, Stevinweg 1, Delft 2628CN, the Netherlands
| | - Mario Pronk
- Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, Delft, HZ 2629, the Netherlands
- Royal HaskoningDHV, Laan 1914 35, Amersfoort, AL 3800, the Netherlands
| | - Merle K. de Kreuk
- Section Sanitary Engineering, Department of Water Management, Delft University of Technology, Stevinweg 1, Delft 2628CN, the Netherlands
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30
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Derlon N, Garcia Villodres M, Kovács R, Brison A, Layer M, Takács I, Morgenroth E. Modelling of aerobic granular sludge reactors: the importance of hydrodynamic regimes, selective sludge removal and gradients. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2022; 86:410-431. [PMID: 35960827 DOI: 10.2166/wst.2022.220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Hydraulic selection is a key feature of aerobic granular sludge (AGS) systems but existing aerobic granular sludge (AGS) models neglect those mechanisms: gradients over reactor height (Hreactor), selective removal of slow settling sludge, etc. This study aimed at evaluating to what extent integration of those additional processes into AGS models is needed, i.e., at demonstrating that model predictions (biomass inventory, microbial activities and effluent quality) are affected by such additional model complexity. We therefore developed a new AGS model that includes key features of full-scale AGS systems: fill-draw operation, selective sludge removal, distinct settling models for flocs/granules. We then compared predictions of our model to those of a fully mixed AGS model. Our results demonstrate that hydraulic selection can be predicted with an assembly of four continuous stirred tank reactors in series together with a correction code for plug-flow. Concentration gradients over the reactor height during settling/plug-flow feeding strongly impact the predictions of aerobic granular sludge models in terms of microbial selection, microbial activities and ultimately effluent quality. Hydraulic selection is a key to predict selection of storing microorganisms (phosphorus-accumulating organisms (PAO) and glycogen-accumulating organisms (GAO)) and in turn effluent quality in terms of total phosphorus, and for predicting effluent solid concentration and dynamic during plug-flow feeding.
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Affiliation(s)
- Nicolas Derlon
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf 8600, Switzerland E-mail:
| | - Mercedes Garcia Villodres
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf 8600, Switzerland E-mail: ; WABAG Water Technology Ltd, Bürglistrasse 31, CH-8400 Winterthur, Switzerland
| | - Róbert Kovács
- Dynamita, 7 Eoupe, La Redoute, Nyons 26110, France; Nonlineum, 37 Perjes str., Budapest 1165, Hungary
| | - Antoine Brison
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf 8600, Switzerland E-mail:
| | - Manuel Layer
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf 8600, Switzerland E-mail:
| | - Imre Takács
- Dynamita, 7 Eoupe, La Redoute, Nyons 26110, France
| | - Eberhard Morgenroth
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf 8600, Switzerland E-mail: ; ETH Zürich, Institute of Environmental Engineering, Zürich 8093, Switzerland
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31
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Wu Z, Gao J, Cui Y, Wang Z, Zhao Y, Zhang H, Guo Y, Li Z. Feeding low-level benzethonium chloride can promote the start-up, fast recovery and long-term stable maintenance of partial nitrification for low-ammonium wastewater. BIORESOURCE TECHNOLOGY 2022; 353:127152. [PMID: 35421565 DOI: 10.1016/j.biortech.2022.127152] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 04/08/2022] [Accepted: 04/09/2022] [Indexed: 06/14/2023]
Abstract
The establishment of stable partial nitrification (PN) is beneficial to promote the application of anaerobic ammonium oxidation, especially for low-ammonium wastewater. This study demonstrated an innovative approach for achieving PN through feeding low-level benzethonium chloride (BZC). PN was started and maintained for 125 days after the sequential feeding of 0.2 and 1 mg/L BZC for 50 days. The damaged PN recovered rapidly within eight days by feeding 2 mg/L BZC, and it thrived for more than 172 days, indicating that nitrite-oxidizing bacteria did not adapt to BZC. The removal of BZC changed from adsorption to degradation gradually. Increased extracellular polymeric substances secretion and altered protein secondary structures explained sludge granulation during BZC feeding, which may be closely related to long-term stable maintenance of PN. PICRUSt2 revealed the underlying microbial mechanisms in depth. Overall, this research proposed a novel scheme to achieve robust PN treating low-ammonium wastewater through feeding low-level BZC.
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Affiliation(s)
- Zejie Wu
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Faculty of Environment and Life, Beijing University of Technology, Beijing 100124, China
| | - Jingfeng Gao
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Faculty of Environment and Life, Beijing University of Technology, Beijing 100124, China.
| | - Yingchao Cui
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Faculty of Environment and Life, Beijing University of Technology, Beijing 100124, China
| | - Zhiqi Wang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Faculty of Environment and Life, Beijing University of Technology, Beijing 100124, China
| | - Yifan Zhao
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Faculty of Environment and Life, Beijing University of Technology, Beijing 100124, China
| | - Haoran Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Faculty of Environment and Life, Beijing University of Technology, Beijing 100124, China
| | - Yi Guo
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Faculty of Environment and Life, Beijing University of Technology, Beijing 100124, China
| | - Ziqiao Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Faculty of Environment and Life, Beijing University of Technology, Beijing 100124, China
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32
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BOU-SARKIS A, PAGLIACCIA B, RIC A, DERLON N, PAUL E, BESSIERE Y, GIRBAL-NEUHAUSER E. Effects of alkaline solvents and heating temperatures on the solubilization and degradation of gel-forming Extracellular Polymeric Substances extracted from aerobic granular sludge. Biochem Eng J 2022. [DOI: 10.1016/j.bej.2022.108500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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33
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Chang M, Liang B, Zhang K, Wang Y, Jin D, Zhang Q, Hao L, Zhu T. Simultaneous shortcut nitrification and denitrification in a hybrid membrane aerated biofilms reactor (H-MBfR) for nitrogen removal from low COD/N wastewater. WATER RESEARCH 2022; 211:118027. [PMID: 35026548 DOI: 10.1016/j.watres.2021.118027] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 12/11/2021] [Accepted: 12/28/2021] [Indexed: 06/14/2023]
Abstract
The residues of nitrogen contaminants due to insufficient organic carbon sources in sewage has always been the main problem faced by wastewater treatment plants in the process of nitrogen removal. In this study, simultaneous shortcut nitrification and denitrification (SND) was achieved in the hybrid membrane aerated biofilm reactor (H-MBfR) for treating low COD/N ratio (∼x223C 4: 1) wastewater. The effects of the aeration pressure and the influent COD/N ratio in H-MBfR were investigated and further optimized by the response surface methodology (RSM). By controlling the dissolved oxygen to achieve SND, the removal efficiencies of NH4+-N, COD and TN of low COD/N ratio wastewater reached maximum values of 95.52%, 96.61% and 72.23%, respectively. Microbial community analysis showed that the influent COD/N ratio had an obvious influence on the microbial community structure. In particular, ammonia oxidizing bacteria (AOB) and denitrifying bacteria had a good commensalism when the COD/N ratio was 4.3. Compared to control reactor, the analysis of membrane bio-fouling showed that H-MBfR has a lower amount of extracellular polymeric substance (EPS) on membrane and a low concentration of MLSS in bulk liquid, which is helpful for the longer-term operation of H-MBfR.
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Affiliation(s)
- Mingdong Chang
- School of Mechanical Engineering and Automation, Northeastern University, 3-11, Wenhua Road, Heping District, Shenyang 110819, China
| | - Baorui Liang
- School of Mechanical Engineering and Automation, Northeastern University, 3-11, Wenhua Road, Heping District, Shenyang 110819, China
| | - Kuo Zhang
- College of Environmental Sciences and Engineering, Peking University, No.5 Yiheyuan Road Haidian District, Beijing, 100871, P.R. China
| | - Youzhao Wang
- School of Mechanical Engineering and Automation, Northeastern University, 3-11, Wenhua Road, Heping District, Shenyang 110819, China; DongYuan Environment S&T, 400-19, Zhihui 2 Road, Hunnan District, Shenyang 110004, China.
| | - Dongtian Jin
- School of Mechanical Engineering and Automation, Northeastern University, 3-11, Wenhua Road, Heping District, Shenyang 110819, China
| | - Qingjun Zhang
- School of Mechanical Engineering and Automation, Northeastern University, 3-11, Wenhua Road, Heping District, Shenyang 110819, China
| | - Liying Hao
- Department of Pharmaceutical Toxicology, School of Pharmacy, China Medical University, Shenyang, 110112, China.
| | - Tong Zhu
- School of Mechanical Engineering and Automation, Northeastern University, 3-11, Wenhua Road, Heping District, Shenyang 110819, China.
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34
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Purba LDA, Md Khudzari J, Iwamoto K, Mohamad SE, Yuzir A, Abdullah N, Shimizu K, Hermana J. Discovering future research trends of aerobic granular sludge using bibliometric approach. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 303:114150. [PMID: 34864588 DOI: 10.1016/j.jenvman.2021.114150] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 11/07/2021] [Accepted: 11/22/2021] [Indexed: 06/13/2023]
Abstract
The advantageous characteristics of aerobic granular sludge (AGS) have led to their increasing popularities among academics and industrial players. However, there has been no bibliometric report on current and future research trends of AGS. This study utilized the available reports of AGS in the Scopus database for comprehensive bibliometric analyses using VOSviewer software. A total of 1203 research articles from 1997 to 2020 were analyzed. The dominance of the Netherlands and China were revealed by the high number of publications and citations. Nevertheless, the Netherlands exhibited higher average citation per article at 76.4. A recent process of AGS involving biochar and algal addition were also identified. Meanwhile, the application of AGS for antibiotic containing wastewater as well as possibility of resource recovery were recently reported and was expected to expand in the future. It was suggested that application of AGS would develop further along with the development of sustainable wastewater treatment process.
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Affiliation(s)
- Laila Dina Amalia Purba
- Malaysia-Japan International Institute of Technology (MJIIT), Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, 54100, Kuala Lumpur, Malaysia
| | - Jauharah Md Khudzari
- Department of Chemical and Environmental Engineering, Malaysia-Japan International Institute of Technology (MJIIT), Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, 54100, Kuala Lumpur, Malaysia
| | - Koji Iwamoto
- Department of Chemical and Environmental Engineering, Malaysia-Japan International Institute of Technology (MJIIT), Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, 54100, Kuala Lumpur, Malaysia
| | - Shaza Eva Mohamad
- Department of Chemical and Environmental Engineering, Malaysia-Japan International Institute of Technology (MJIIT), Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, 54100, Kuala Lumpur, Malaysia
| | - Ali Yuzir
- Department of Chemical and Environmental Engineering, Malaysia-Japan International Institute of Technology (MJIIT), Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, 54100, Kuala Lumpur, Malaysia
| | - Norhayati Abdullah
- Department of Chemical and Environmental Engineering, Malaysia-Japan International Institute of Technology (MJIIT), Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, 54100, Kuala Lumpur, Malaysia; Associate Director, UTM International, Jalan Sultan Yahya Petra, 54100, Kuala Lumpur, Malaysia.
| | - Kazuya Shimizu
- Faculty of Life and Environmental Sciences, University of Tsukuba, Ibaraki, 305-8572, Japan
| | - Joni Hermana
- Department of Environmental Engineering, Faculty of Civil, Planning and Geoengineering, Institut Teknologi Sepuluh Nopember, Surabaya, 60111, Indonesia
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Castellanos RM, Dezotti M, Bassin JP. COD, nitrogen and phosphorus removal from simulated sewage in an aerobic granular sludge in the absence and presence of natural and synthetic estrogens: Performance and biomass physical properties assessment. Biochem Eng J 2021. [DOI: 10.1016/j.bej.2021.108221] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Effect of an Increased Particulate COD Load on the Aerobic Granular Sludge Process: A Full Scale Study. Processes (Basel) 2021. [DOI: 10.3390/pr9081472] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
High concentrations of particulate COD (pCOD) in the influent of aerobic granular sludge (AGS) systems are often associated to small granule diameter and a large fraction of flocculent sludge. At high particulate concentrations even granule stability and process performance might be compromised. However, pilot- or full-scale studies focusing on the effect of real wastewater particulates on AGS are scarce. This study describes a 3-month period of increased particulate loading at a municipal AGS wastewater treatment plant. The pCOD concentration of the influent increased from 0.5 g COD/L to 1.3 g COD/L, by adding an untreated slaughterhouse wastewater source to the influent. Sludge concentration, waste sludge production and COD and nutrient removal performance were monitored. Furthermore, to investigate how the sludge acclimatises to a higher influent particulate content, lipase and protease hydrolytic activities were studied, as well as the microbial community composition of the sludge. The composition of the granule bed and nutrient removal efficiency did not change considerably by the increased pCOD. Interestingly, the biomass-specific hydrolytic activities of the sludge did not increase during the test period either. However, already during normal operation the aerobic granules and flocs exhibited a hydrolytic potential that exceeded the influent concentrations of proteins and lipids. Microbial community analysis also revealed a high proportion of putative hydrolysing and fermenting organisms in the sludge, both during normal operation and during the test period. The results of this study highlight the robustness of the full-scale AGS process, which can bear a substantial increase in the influent pCOD concentration during an extended period.
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Zhou JH, Ren Q, Xu XL, Fang JY, Wang T, Wang KM, Wang HY. Enhancing stability of aerobic granules by microbial selection pressure using height-adjustable influent strategy. WATER RESEARCH 2021; 201:117356. [PMID: 34147742 DOI: 10.1016/j.watres.2021.117356] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 05/15/2021] [Accepted: 06/07/2021] [Indexed: 06/12/2023]
Abstract
Optimizing granules size distribution is critical for both reactor performance and stability. In this research, an optimal size range of 1800 to 3000 μm was proposed regarding mass transfer and granules stability based on granules developed at DO around 8.0 mg L-1 with the feed COD:N:P at 100:5:1. A height-adjustable influent strategy was applied to facilitate the nutrient storage of granules at optimum size range via microbial selective pressure. Results suggested insufficient hydraulic shear stress led to overgrowth of granules size. High abundance of filamentous bacteria (Thiothrix sp.) was observed in oversized granules, which detached and affected the remaining granules, resulting in severe sludge bulking. Strong hydraulic shear stress suppressed uncontrolled growth of granules. However, fewer abundance of simultaneous nitrification and denitrification (SND) bacterium was acquired, which led to unfavored SND effect and total nitrogen (TN) removal efficiency. The height-adjustable influent strategy facilitated the poly-β-hydroxybutyrate (PHB) storage of granules at optimum size range, while limiting the overgrowth of granules size. Additionally, more than 87.51% of total granules situated in optimal sizes range, which led to higher abundance of SND bacterium and higher TN removal efficiency.
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Affiliation(s)
- Jia-Heng Zhou
- College of Civil Engineering and Architecture, Zhejiang University of Technology, Hangzhou 310014, China.
| | - Qing Ren
- College of Civil Engineering and Architecture, Zhejiang University of Technology, Hangzhou 310014, China
| | - Xiao-Lei Xu
- College of Civil Engineering and Architecture, Zhejiang University of Technology, Hangzhou 310014, China
| | - Jing-Yuan Fang
- College of Civil Engineering and Architecture, Zhejiang University of Technology, Hangzhou 310014, China
| | - Tao Wang
- College of Civil Engineering and Architecture, Zhejiang University of Technology, Hangzhou 310014, China
| | - Kan-Ming Wang
- College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Hong-Yu Wang
- College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
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Nguyen Quoc B, Armenta M, Carter JA, Bucher R, Sukapanpotharam P, Bryson SJ, Stahl DA, Stensel HD, Winkler MKH. An investigation into the optimal granular sludge size for simultaneous nitrogen and phosphate removal. WATER RESEARCH 2021; 198:117119. [PMID: 33957310 DOI: 10.1016/j.watres.2021.117119] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 03/29/2021] [Accepted: 04/01/2021] [Indexed: 06/12/2023]
Abstract
An aerobic granular sludge (AGS) pilot plant fed with a mixture of acetate amended centrate and secondary effluent was used to investigate the optimal granule size range for simultaneous nitrification and denitrification (SND) and ortho-phosphate removal. The anaerobic phase was mixed to understand how AGS will perform if integrated with a continuous flow activated sludge system that cannot feed the influent through the settled sludge bed. Five different granule size fractions were taken from the pilot (operated at DO setpoint of 2mgO2/L) and each size was subjected to activity tests in a well-controlled lab-scale AGS reactor at four dissolved oxygen (DO) concentrations of 1, 2, 3, and 4 mgO2/L. The size fractions were: 212 - 600 µm, 600 - 1000 µm, 1000 - 1400 µm, 1400 - 2000 µm, and >2000 µm. The smallest size range (212 - 600 µm) had the highest nitrification and phosphate removal rates at DO setpoints from 1 - 3 mgO2/L, which was attributed to the higher aerobic volume fraction in small granules and hence a higher abundance of phosphorus accumulating organisms (PAO) and ammonia oxidizing bacteria (AOB). In comparison, large granules (>1000 µm) had 1.4 - 4.7 times lower ammonia oxidation rates than the smallest size range, which aligned with their lower AOB abundance relative to granule biomass. The granules with the highest anoxic volume fraction had the highest abundance of nitrite reductase genes (nir gene) but did not show the highest specific nitrogen removal rate. Instead, smaller granules (212 - 600 and 600 - 1000 µm), which had a lower nir gene abundance, had the highest specific nitrogen removal rates (1.2 - 3.1 times higher than larger granules) across all DO values except at 4 mgO2/L. At a DO setpoint of 4 mgO2/L, nitrite production by ammonia oxidation (ammonia monooxygenase) exceeded nitrite reduction by nitrite reductase in granules smaller than 1000 µm, in addition, some denitrifying heterotrophs switched to oxygen utilization in deeper layers hence suppressing denitrification activity. At the DO range of 2 - 4 mg/L, granular size had a greater effect on nutrient removal than DO. Therefore, for AGS developed at an average DO setpoint of 2 mgO2/L, selecting for size fractions in the range of 212 - 1000 µm and avoiding DO values higher than 3 mgO2/L can achieve both a higher nitrogen removal capacity and energy savings. This study is the first to investigate the influence of different DO values on SND and biological phosphorus removal performance of different aerobic granular sludge sizes.
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Affiliation(s)
- Bao Nguyen Quoc
- Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, USA.
| | - Maxwell Armenta
- Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, USA
| | - John A Carter
- Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, USA
| | - Robert Bucher
- Resource Recovery Section, Wastewater Treatment Division, King County Department of Natural Resources, Parks, WA, USA
| | - Pardi Sukapanpotharam
- Resource Recovery Section, Wastewater Treatment Division, King County Department of Natural Resources, Parks, WA, USA
| | - Samuel J Bryson
- Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, USA
| | - David A Stahl
- Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, USA
| | - H David Stensel
- Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, USA
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Wei SP, Nguyen Quoc B, Shapiro M, Chang PH, Calhoun J, Winkler MKH. Application of aerobic kenaf granules for biological nutrient removal in a full-scale continuous flow activated sludge system. CHEMOSPHERE 2021; 271:129522. [PMID: 33450421 DOI: 10.1016/j.chemosphere.2020.129522] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2020] [Revised: 12/28/2020] [Accepted: 12/29/2020] [Indexed: 06/12/2023]
Abstract
Aerobic granular sludge (AGS) is a biofilm technology that offers more treatment capacity in comparison to activated sludge. The integration of AGS into existing continuous-flow activated sludge systems is of great interest as process intensification can be achieved without the use of plastic-based biofilm carriers. Such integration should allow good separation of granules/flocs and ideally with minor retrofitting, making it an ongoing challenge. This study utilized an all-organic media carrier made of porous kenaf plant stalks with high surface areas to facilitate biofilm attachment and granule development. A 5-stage Bardenpho plant was upgraded with the addition of kenaf media and a rotary drum screen to retain the larger particles from the secondary clarifier underflow whereas flocs were selectively wasted. Startup took 5 months with a sludge volume index (SVI) reduction from >200 to 50 mL g-1. Most of the kenaf granules fell in the size range of 600-1400 μm and had a clear biofilm layer. The wet biomass density, SVI30, and SVI30/SVI5 of the kenaf granules were 1035 g L-1, 30.6 mL g-1, and 1.0, respectively, which met the standards of aerobic granules. Improved stability of biological phosphorus removal performance enabled a 25% reduction in sodium aluminate usage. Microbial activities of kenaf granules were compared with aerobic granules, showing comparable N and P removal rates and presence of ammonium-oxidizing bacteria and polyphosphate-accumulating organisms in the outer 50-60 μm layer of the granule. This work is the first viable example for integrating fully organic biofilm particles in existing continuous-flow systems.
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Affiliation(s)
- Stephany P Wei
- University of Washington, Department of Civil & Environmental Engineering, 616 Northlake Place, Seattle, WA, 98195, USA.
| | - Bao Nguyen Quoc
- University of Washington, Department of Civil & Environmental Engineering, 616 Northlake Place, Seattle, WA, 98195, USA.
| | - Madelyn Shapiro
- University of Washington, Department of Civil & Environmental Engineering, 616 Northlake Place, Seattle, WA, 98195, USA.
| | | | | | - Mari K H Winkler
- University of Washington, Department of Civil & Environmental Engineering, 616 Northlake Place, Seattle, WA, 98195, USA.
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40
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Castellanos RM, Bassin JP, Bila DM, Dezotti M. Biodegradation of natural and synthetic endocrine-disrupting chemicals by aerobic granular sludge reactor: Evaluating estrogenic activity and estrogens fate. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 274:116551. [PMID: 33529898 DOI: 10.1016/j.envpol.2021.116551] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Revised: 01/12/2021] [Accepted: 01/20/2021] [Indexed: 06/12/2023]
Abstract
In this study, the biodegradation of endocrine-disrupting chemicals (EDCs) (namely the natural and synthetic estrogens 17β-estradiol (E2) and 17α-ethinylestradiol (EE2), respectively) was assessed in an aerobic granular sludge (AGS) sequencing batch reactor (SBR) treating simulated domestic sewage. To better understand the fate of these compounds, their concentrations were determined in both liquid and solid (biomass) samples. Throughout the operation of the reactor, subjected to alternating anaerobic and aerated conditions, the removal of the hormones, both present in the influent at a concentration of 20 μg L-1, amounted to 99% (for E2) and 93% (for EE2), with the latter showing higher resistance to biodegradation. Through yeast estrogen screen assays, an average moderate residual estrogenic activity (0.09 μg L-1 EQ-E2) was found in the samples analysed. E2 and EE2 profiles over the SBR cycle suggest a rapid initial adsorption of these compounds on the granular biomass occurring anaerobically, followed by biodegradation under aeration. A possible sequence of steps for the removal of the micropollutants, including the key microbial players, was proposed. Besides the good capability of the AGS on EDCs removal, the results revealed high removal efficiencies (>90%) of COD, ammonium and phosphate. Most of the incoming organics (>80%) were consumed under anaerobic conditions, when phosphate was released (75.2 mgP L-1). Nitrification and phosphate uptake took place along the aeration phase, with effluent ammonium and phosphate levels around 2 mg L-1. Although nitrite accumulation took place over the cycle, nitrate consisted of the main oxidized nitrogen form in the effluent. The specific ammonium and phosphate uptake rates attained in the SBR were found to be 3.3 mgNH4+-N gVSS-1.h-1 and 6.7 mgPO43--P gVSS-1 h-1, respectively, while the specific denitrification rate corresponded to 1.0 mgNOx--N gVSS-1 h-1.
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Affiliation(s)
- Reynel Martínez Castellanos
- Chemical Engineering Program, COPPE, Federal University of Rio de Janeiro, P.O. Box 68502, 21941-972, Rio de Janeiro, Brazil
| | - João P Bassin
- Chemical Engineering Program, COPPE, Federal University of Rio de Janeiro, P.O. Box 68502, 21941-972, Rio de Janeiro, Brazil.
| | - Daniele M Bila
- Department of Environmental and Sanitary Engineering, State University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Márcia Dezotti
- Chemical Engineering Program, COPPE, Federal University of Rio de Janeiro, P.O. Box 68502, 21941-972, Rio de Janeiro, Brazil
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41
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Guo Y, Shi W, Zhang B, Li W, Lens PNL. Effect of voltage intensity on the nutrient removal performance and microbial community in the iron electrolysis-integrated aerobic granular sludge system. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 274:116604. [PMID: 33548671 DOI: 10.1016/j.envpol.2021.116604] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Revised: 01/19/2021] [Accepted: 01/24/2021] [Indexed: 06/12/2023]
Abstract
The effects of voltage intensity on the nutrient removal performance and microbial community in the iron electrolysis-integrated aerobic granular sludge (AGS) system were investigated over a period of 15 weeks. Results revealed that the application outcomes of iron electrolysis for AGS systems relied on voltage intensity. When a constant voltage of 1.5 V was applied, the sludge granulation was most obviously accelerated with a specific growth rate of the sludge diameter of 0.078 day-1, and the removal efficiencies of total nitrogen (TN) and total phosphorus (TP) increased by 14.1% and 20.2%, respectively, compared to the control reactor (without the iron electrolysis-integration). Moreover, the AGS developed at different voltages included different microbial communities, whose shifts were driven by the Fe content and the average diameter of AGS. Both heterotrophic nitrifiers and mixotrophic denitrifiers were significantly enriched in the AGS developed at 1.5 V, which effectively enhanced TN removal. Together with the response of the functional genes involved in Fe, N, and P metabolism, the electrolytic iron-driven nutrient degradation pathway was further elaborated. Overall, this study clarified the optimum voltage condition when iron electrolysis was integrated into the AGS system, and revealed the enhancement mechanism of this coupling technology on nutrient removal during the treatment of low-strength municipal wastewater.
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Affiliation(s)
- Yuan Guo
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Wenxin Shi
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China; College of Environment and Ecology, Chongqing University, Chongqing, 400044, China.
| | - Bing Zhang
- College of Environment and Ecology, Chongqing University, Chongqing, 400044, China.
| | - Weiguang Li
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Piet N L Lens
- UNESCO-IHE, Institute for Water Education, Westvest 7, 2601, DA Delft, the Netherlands
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42
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Wang X, Li J, Zhang X, Chen Z, Shen J, Kang J. Impact of hydraulic retention time on swine wastewater treatment by aerobic granular sludge sequencing batch reactor. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:5927-5937. [PMID: 32981014 DOI: 10.1007/s11356-020-10922-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 09/17/2020] [Indexed: 06/11/2023]
Abstract
In this study, the effect of hydraulic retention time (HRT) on the performance of aerobic granular sludge (AGS) treating swine wastewater (SW) in sequencing batch reactor (SBR) was investigated. The HRT was set at 4.8, 6, 8, 12, and 16 h and performed in five parallel aerobic granular sludge sequence batch reactors (AGSBRs), respectively. The results showed that sedimentation performance and biomass concentration were improved by decreasing the HRT from 16 to 8 h. However, when further decreasing HRT from 8 to 4.8 h, the AGS performance became worse. The AGS process with HRT of 8 h exhibited high pollutant removal efficiency, and an abundant microbial community and a stable microbial community structure were observed. High-throughput 16S rRNA analysis revealed that there were significant differences between the microorganisms in AGS samples with HRT of 8 h at the phylum level and that the dominant microbes changed as the process proceeded. At the genus level, the species and relative abundance of microorganisms gradually evolved for AGS stability in all cases.
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Affiliation(s)
- Xiaochun Wang
- Shenzhen Key Laboratory of Water Resource Application and Environmental Pollution Control, Department of Civil and Environmental Engineering, Harbin Institute of Technology (Shenzhen), 518055, Shenzhen, China
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Ji Li
- Shenzhen Key Laboratory of Water Resource Application and Environmental Pollution Control, Department of Civil and Environmental Engineering, Harbin Institute of Technology (Shenzhen), 518055, Shenzhen, China
| | - Xiaolei Zhang
- Shenzhen Key Laboratory of Water Resource Application and Environmental Pollution Control, Department of Civil and Environmental Engineering, Harbin Institute of Technology (Shenzhen), 518055, Shenzhen, China.
| | - Zhonglin Chen
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Jimin Shen
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Jing Kang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
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Nguyen Quoc B, Wei S, Armenta M, Bucher R, Sukapanpotharam P, Stahl DA, Stensel HD, Winkler MKH. Aerobic granular sludge: Impact of size distribution on nitrification capacity. WATER RESEARCH 2021; 188:116445. [PMID: 33039834 DOI: 10.1016/j.watres.2020.116445] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 09/01/2020] [Accepted: 09/22/2020] [Indexed: 06/11/2023]
Abstract
The relationship between ammonia oxidation rate, nitrifiers population, and modelled aerobic zone volume in different granule sizes was investigated using aerobic granular sludge from a pilot-scale reactor. The pilot was fed with centrate and secondary effluent amended with acetate as the main carbon source. The maximum specific ammonia oxidation rates and community composition of different aerobic granular sludge size fractions were evaluated by batch tests, quantitative PCR, and genomic analysis. Small (331µm) granules had a 4.72 ± 0.09 times higher maximum specific ammonia oxidizing rate per 1 gVSS, and a 4.05 ± 0.17 times higher specific amoA gene copy number than large (2225µm) granules per 1 gram of wet biomass. However, when related to surface area, small granules had 1.43 ± 0.01 times lower maximum specific ammonia oxidation rate and a 1.66 ± 0.04 times lower specific amoA gene copy number per unit surface than large granules. Experimental results aligned with modeling results in which smaller granules had a higher specific aerobic zone volume to biomass and lower specific aerobic zone volume to surface area. Aerobic granular sludge reactors having the same average diameter of granules may have very different proportions of granule size fractions and hence possess different nitrification rates. Therefore, instead of the commonly reported average granule diameter, a new method was proposed to determine the aerobic volume density per sample, which correlated well with the nitrification rate. This work provides a roadmap to control nitrification capacity by two methods: (a) crushing larger granules into smaller fractions, or (b) increasing the mixed liquor suspended solid concentration to increase the total aerobic zone volume of the system.
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Affiliation(s)
- Bao Nguyen Quoc
- Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, USA.
| | - Stephany Wei
- Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, USA.
| | - Maxwell Armenta
- Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, USA.
| | - Robert Bucher
- Resource Recovery, Wastewater Treatment Division, King County Department of Natural Resources and Parks, WA, USA.
| | - Pardi Sukapanpotharam
- Resource Recovery, Wastewater Treatment Division, King County Department of Natural Resources and Parks, WA, USA.
| | - David A Stahl
- Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, USA.
| | - H David Stensel
- Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, USA.
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Layer M, Bock K, Ranzinger F, Horn H, Morgenroth E, Derlon N. Particulate substrate retention in plug-flow and fully-mixed conditions during operation of aerobic granular sludge systems. WATER RESEARCH X 2020; 9:100075. [PMID: 33196033 PMCID: PMC7645637 DOI: 10.1016/j.wroa.2020.100075] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 10/03/2020] [Accepted: 10/19/2020] [Indexed: 06/11/2023]
Abstract
Particulate substrate (XB) is the major organic substrate fraction in most municipal wastewaters. However, the impact of XB on aerobic granular sludge (AGS) systems is not fully understood. This study evaluated the physical retention of XB in AGS sequencing batch reactor (SBR) during anaerobic plug-flow and then aerobic fully-mixed conditions. The influence of different sludge types and operational variables on the extent and mechanisms of XB retention in AGS SBR were evaluated. XB mass-balancing and magnetic resonance imaging (MRI) were applied. During the anaerobic plug-flow feeding, most XB was retained in the first few cm of the settled sludge bed within the interstitial voids, where XB settled and accumulated ultimately resulting in the formation of a filter-cake. Sedimentation and surface filtration were thus the dominant XB retention mechanisms during plug-flow conditions, indicating that contact and attachment of XB to the biomass was limited. XB retention was variable and influenced by the XB influent concentration, sludge bed composition and upflow feeding velocity (vww). XB retention increased with larger XB influent concentrations and lower vww, which demonstrated the importance of sedimentation on XB retention during plug-flow conditions. Hence, large fractions of influent XB likely re-suspended during aerobic fully-mixed conditions, where XB then preferentially and rapidly attached to the flocs. During fully-mixed conditions, increasing floc fractions, longer mixing times and larger XB concentrations increased XB retention. Elevated XB retention was observed after short mixing times < 60 min when flocs were present, and the contribution of flocs towards XB retention was even more pronounced for short mixing times < 5 min. Overall, our results suggest that flocs occupy an environmental niche that results from the availability of XB during aerobic fully-mixed conditions of AGS SBR. Therefore, a complete wash-out of flocs is not desirable in AGS systems treating municipal wastewater.
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Affiliation(s)
- M. Layer
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, 8600, Dübendorf, Switzerland
- ETH Zürich, Institute of Environmental Engineering, 8093, Zürich, Switzerland
| | - K. Bock
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, 8600, Dübendorf, Switzerland
| | - F. Ranzinger
- Engler-Bunte-Institut, Karlsruhe Institute of Technology, 76131, Karlsruhe, Germany
| | - H. Horn
- Engler-Bunte-Institut, Karlsruhe Institute of Technology, 76131, Karlsruhe, Germany
| | - E. Morgenroth
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, 8600, Dübendorf, Switzerland
- ETH Zürich, Institute of Environmental Engineering, 8093, Zürich, Switzerland
| | - N. Derlon
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, 8600, Dübendorf, Switzerland
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Lai C, Guo Y, Cai Q, Yang P. Enhanced nitrogen removal by simultaneous nitrification-denitrification and further denitrification (SND-DN) in a moving bed and constructed wetland (MBCW) integrated bioreactor. CHEMOSPHERE 2020; 261:127744. [PMID: 32739690 DOI: 10.1016/j.chemosphere.2020.127744] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 07/04/2020] [Accepted: 07/14/2020] [Indexed: 06/11/2023]
Abstract
With the main objective of improving the removal of nitrogen from domestic wastewater and more sustainably, a moving bed and constructed wetland (MBCW) integrated bioreactor was fabricated and evaluated with continuous and intermittent aeration operations. The hybrid system achieves average removal efficiencies up to 90.4 ± 0.8% of chemical oxygen demand (COD), 91.8 ± 1.2% of ammonia nitrogen (NH4+-N), and 77.0 ± 2.6% of total nitrogen (TN), respectively, through a simultaneous nitrification-denitrification and further denitrification (SND-DN) process. This occurs through an intermittent aeration operation followed by continuous aeration with a dissolved oxygen (DO) of 4.0 mg L-1 due to the complementary and coordinated action of mixed biocarriers. It has resulted in the improvement of the efficiency of SND from 5.9 to 35.3% and in the removal via wetland for DN, between 2.42 and 2.45 g m-2·d-1, respectively. The analysis of extracellular polymeric substances (EPS) and high-throughput sequencing demonstrated the enhanced SND mechanism and the evolution of microbial species within the biofilm structure. The total relative abundance of nitrifying bacteria, more aggregated outside the biofilm, decreased by 7.66% compared to denitrifying bacteria, mostly accumulated inside, which increased by 5.49%, respectively.
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Affiliation(s)
- Changmiao Lai
- College of Architecture and Environment, Sichuan University, Chengdu, 610065, China.
| | - Yong Guo
- School of Chemical Engineering, Sichuan University, Chengdu, 610065, China.
| | - Qin Cai
- College of Architecture and Environment, Sichuan University, Chengdu, 610065, China.
| | - Ping Yang
- College of Architecture and Environment, Sichuan University, Chengdu, 610065, China.
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Schambeck CM, Girbal-Neuhauser E, Böni L, Fischer P, Bessière Y, Paul E, da Costa RHR, Derlon N. Chemical and physical properties of alginate-like exopolymers of aerobic granules and flocs produced from different wastewaters. BIORESOURCE TECHNOLOGY 2020; 312:123632. [PMID: 32531737 DOI: 10.1016/j.biortech.2020.123632] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 05/29/2020] [Accepted: 06/02/2020] [Indexed: 06/11/2023]
Abstract
The influence of wastewater (WW) composition and the bioaggregates types (floccular vs. aerobic granular sludge - AGS) on the content, physical-chemical, hydrogel and rheological properties of Alginate-Like Exopolymers (ALE) was studied. Results showed that ALE are a complex mixture of proteins, humic acids and polysaccharides. Overall, rather similar ALE content and composition was observed for the different types of sludge. Only the AGS fed with acetate and propionate yielded significantly larger amount of ALE (261 ± 33 mg VSALE/g VSsludge, +49%) and of uronic sugars in ALE (254 ± 32 mgglucuronic acid/g VSALE, +62%) than bioaggregates fed with no/very little volatile fatty acids. Mannuronic acids are involved in the cohesion of the hydrogels. ALE hydrogels elasticity changed significantly with the type/origin of the bioaggregates. ALE hydrogels elasticity from AGS was always higher than from flocs when fed with real WW. Hence, different types of sludge impact the properties of the recovered ALE.
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Affiliation(s)
- Cássio Moraes Schambeck
- Sanitary and Environmental Engineering Department, Federal University of Santa Catarina, 88040-970 Florianópolis, Brazil; Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland
| | - Elisabeth Girbal-Neuhauser
- Laboratoire de Biotechnologies Agroalimentaire et Environmentale (LBAE), Université Paul Sabatier, 31000 Toulouse, France
| | - Lukas Böni
- Institute of Food, Nutrition and Health, Department of Health Science and Technology, ETH Zürich, 8092 Zürich, Switzerland
| | - Peter Fischer
- Institute of Food, Nutrition and Health, Department of Health Science and Technology, ETH Zürich, 8092 Zürich, Switzerland
| | | | - Etienne Paul
- TBI, Université de Toulouse, CNRS, INRA, INSA, Toulouse, France
| | - Rejane Helena Ribeiro da Costa
- Sanitary and Environmental Engineering Department, Federal University of Santa Catarina, 88040-970 Florianópolis, Brazil
| | - Nicolas Derlon
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland.
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