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Yang Y, Li G, Li Z, Lu L. The roles of typical emerging pollutants on N 2O emissions during biological nitrogen removal from wastewater. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 930:172851. [PMID: 38685430 DOI: 10.1016/j.scitotenv.2024.172851] [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: 12/18/2023] [Revised: 04/26/2024] [Accepted: 04/26/2024] [Indexed: 05/02/2024]
Abstract
N2O as a potent greenhouse gas often generates in the biological nitrogen removal (BNR) processes during wastewater treatment, which makes BNR become an important greenhouse gas emission source. The emerging pollutants (EPs) are ubiquitous in wastewater and they have shown to influence the BNR processes. However, the deep discussion on potential impacts of EPs on N2O emissions during BNR is rare. Moreover, the experimental parameters for EPs investigation in most of literatures are generally not in line with real-world BNR processes, which calls for deep elucidating the roles of EPs on N2O production and emission. In this work, a critical review summarizes the existing literature about influences of typical EPs on N2O emissions and associated mechanisms during BNR, and it discusses the impacts of some easily overlooked factors, such as real EPs environmental concentrations, EPs bioaccumulation, and multiple EPs coexistence on N2O emissions. This review will provide an insight into exploring and mitigating threats posed by typical EPs on N2O emissions.
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Affiliation(s)
- Ying Yang
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen, Shenzhen 518055, China
| | - Guifeng Li
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen, Shenzhen 518055, China
| | - Zhida Li
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen, Shenzhen 518055, China
| | - Lu Lu
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen, Shenzhen 518055, China.
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2
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Qiu Y, Ekström S, Valverde-Pérez B, Smets BF, Climent J, Domingo-Félez C, Cuenca RM, Plósz BG. Numerical modelling of surface aeration and N 2O emission in biological water resource recovery. WATER RESEARCH 2024; 255:121398. [PMID: 38503179 DOI: 10.1016/j.watres.2024.121398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 02/15/2024] [Accepted: 02/27/2024] [Indexed: 03/21/2024]
Abstract
Biokinetic modelling of N2O production and emission has been extensively studied in the past fifteen years. In contrast, the physical-chemical hydrodynamics of activated sludge reactor design and operation, and their impact on N2O emission, is less well understood. This study addresses knowledge gaps related to the systematic identification and calibration of computational fluid dynamic (CFD) simulation models. Additionally, factors influencing reliable prediction of aeration and N2O emission in surface aerated oxidation ditch-type reactor types are evaluated. The calibrated model accurately predicts liquid sensor measurements obtained in the Lynetten Water Resource Recovery Facility (WRRF), Denmark. Results highlight the equal importance of design and operational boundary conditions, alongside biokinetic parameters, in predicting N2O emission. Insights into the limitations of calibrating gas mass-transfer processes in two-phase CFD models of surface aeration systems are evaluated.
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Affiliation(s)
- Yuge Qiu
- Department of Chemical Engineering, University of Bath, Claverton Down, Bath BA2 7AY, UK.
| | - Sara Ekström
- Department of Environmental Engineering, Technical University of Denmark, Bygningstorvet, Building 115, 2800 Kgs., Lyngby, Denmark
| | - Borja Valverde-Pérez
- Department of Environmental Engineering, Technical University of Denmark, Bygningstorvet, Building 115, 2800 Kgs., Lyngby, Denmark
| | - Barth F Smets
- Department of Environmental Engineering, Technical University of Denmark, Bygningstorvet, Building 115, 2800 Kgs., Lyngby, Denmark
| | - Javier Climent
- Department of Mechanical Engineering and Construction, Universitat Jaume I, Av. Vicent Sos Baynat, s/n 12071 Castellón (Spain)
| | - Carlos Domingo-Félez
- Department of Environmental Engineering, Technical University of Denmark, Bygningstorvet, Building 115, 2800 Kgs., Lyngby, Denmark
| | - Raúl Martínez Cuenca
- Department of Mechanical Engineering and Construction, Universitat Jaume I, Av. Vicent Sos Baynat, s/n 12071 Castellón (Spain)
| | - Benedek G Plósz
- Department of Chemical Engineering, University of Bath, Claverton Down, Bath BA2 7AY, UK; SWING - Department of Built Environment, Oslo Metropolitan University, St Olavs plass 0130, Oslo, Norway
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3
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Zhang Z, Xing W, Lu J, Gao X, Jia F, Yao H. Nitrogen removal and nitrous oxide emission in the partial nitritation/anammox process at different reflux ratios. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 906:167520. [PMID: 37788770 DOI: 10.1016/j.scitotenv.2023.167520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 09/29/2023] [Accepted: 09/29/2023] [Indexed: 10/05/2023]
Abstract
The partial nitritation/anammox (PN/A) process has been widely used in wastewater treatment owing to its notable advantages, including a low aeration rate and the non-requirement of an additional carbon source. In practical implementation, nitrite accumulation affects the nitrogen-removal efficiency and the amount of N2O released during the PN/A process. By implementing wastewater reflux, the nitrite concentration can be decreased, thereby achieving a balance between the nitrogen-removal efficiency and N2O release. This study conducted the CANON process with varying reflux ratios of 0 to 300 % and ~300 mg/L ammonium in the influent. The highest removal efficiency of ammonium and total nitrogen (98.2 ± 0.8 and 77.8 ± 2.3 %, respectively) could be achieved at a reflux ratio of 200 %. Further, a reflux ratio of 200 % led to the lowest N2O emission factor (2.21 %), with a 31.74 % reduction in N2O emission compared to the process without refluxing. Additionally, the reactor at a reflux ratio of 200 % presented the highest relative abundance of anaerobic ammonium-oxidizing bacteria (30.98 %) and the lowest proportion of ammonium-oxidizing bacteria (9.57 %). This study aimed to elucidate the impact of the reflux ratio on the nitrogen-removal efficiency of the CANON process and to theoretically explain the influence of different reflux ratios on N2O release. These findings provide a theoretical framework for enhancing the nitrogen-removal efficiency and mitigating carbon emissions in practical applications of the CANON process.
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Affiliation(s)
- Zexi Zhang
- Beijing International Scientific and Technological Cooperation Base of Water Pollution Control Techniques for Antibiotics and Resistance Genes, Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, School of Environment, Beijing Jiaotong University, Beijing 100044, PR China
| | - Wei Xing
- Beijing International Scientific and Technological Cooperation Base of Water Pollution Control Techniques for Antibiotics and Resistance Genes, Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, School of Environment, Beijing Jiaotong University, Beijing 100044, PR China.
| | - Jia Lu
- Beijing International Scientific and Technological Cooperation Base of Water Pollution Control Techniques for Antibiotics and Resistance Genes, Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, School of Environment, Beijing Jiaotong University, Beijing 100044, PR China
| | - Xinyu Gao
- Beijing International Scientific and Technological Cooperation Base of Water Pollution Control Techniques for Antibiotics and Resistance Genes, Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, School of Environment, Beijing Jiaotong University, Beijing 100044, PR China
| | - Fangxu Jia
- Beijing International Scientific and Technological Cooperation Base of Water Pollution Control Techniques for Antibiotics and Resistance Genes, Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, School of Environment, Beijing Jiaotong University, Beijing 100044, PR China
| | - Hong Yao
- Beijing International Scientific and Technological Cooperation Base of Water Pollution Control Techniques for Antibiotics and Resistance Genes, Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, School of Environment, Beijing Jiaotong University, Beijing 100044, PR China
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4
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An Z, Zhang Q, Gao X, Ding J, Shao B, Peng Y. Nitrous oxide emissions in novel wastewater treatment processes: A comprehensive review. BIORESOURCE TECHNOLOGY 2024; 391:129950. [PMID: 37926354 DOI: 10.1016/j.biortech.2023.129950] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2023] [Revised: 10/22/2023] [Accepted: 10/28/2023] [Indexed: 11/07/2023]
Abstract
The proliferation of novel wastewater treatment processes has marked recent years, becoming particularly pertinent in light of the strive for carbon neutrality. One area of growing attention within this context is nitrous oxide (N2O) production and emission. This review provides a comprehensive overview of recent research progress on N2O emissions associated with novel wastewater treatment processes, including Anammox, Partial Nitrification, Partial Denitrification, Comammox, Denitrifying Phosphorus Removal, Sulfur-driven Autotrophic Denitrification and n-DAMO. The advantages and challenges of these processes are thoroughly examined, and various mitigation strategies are proposed. An interesting angle that delve into is the potential of endogenous denitrification to act as an N2O sink. Furthermore, the review discusses the potential applications and rationale for novel Anammox-based processes to reduce N2O emissions. The aim is to inform future technology research in this area. Overall, this review aims to shed light on these emerging technologies while encouraging further research and development.
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Affiliation(s)
- Zeming An
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, PR China
| | - Qiong Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, PR China.
| | - Xinjie Gao
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, PR China
| | - Jing Ding
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, PR China
| | - Baishuo Shao
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, PR China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, PR China
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5
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Zhu W, Van Tendeloo M, De Paepe J, Vlaeminck SE. Comparison of typical nitrite oxidizing bacteria suppression strategies and the effect on nitrous oxide emissions in a biofilm reactor. BIORESOURCE TECHNOLOGY 2023; 387:129607. [PMID: 37544532 DOI: 10.1016/j.biortech.2023.129607] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Revised: 07/29/2023] [Accepted: 08/01/2023] [Indexed: 08/08/2023]
Abstract
In mainstream partial nitritation/anammox (PN/A), suppression of nitrite oxidizing bacteria (NOB) and mitigation of N2O emissions are two essential operational goals. The N2O emissions linked to three typical NOB suppression strategies were tested in a covered rotating biological contactor (RBC) biofilm system at 21 °C: (i) low dissolved oxygen (DO) concentrations, and treatments with (ii) free ammonia (FA), and (iii) free nitrous acids (FNA). Low emerged DO levels effectively minimized NOB activity and decreased N2O emissions, but NOB adaptation appeared after 200 days of operation. Further NOB suppression was successfully achieved by periodic (3 h per week) treatments with FA (29.3 ± 2.6 mg NH3-N L-1) or FNA (3.1 ± 0.3 mg HNO2-N L-1). FA treatment, however, promoted N2O emissions, while FNA did not affect these. Hence, biofilm PN/A should be operated at relatively low DO levels with periodic FNA treatment to maximize nitrogen removal efficiency while avoiding high greenhouse gas emissions.
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Affiliation(s)
- Weiqiang Zhu
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium; School of Water Conservancy and Environment, University of Jinan, Jinan 250022, PR China
| | - Michiel Van Tendeloo
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium
| | - Jolien De Paepe
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium
| | - Siegfried E Vlaeminck
- Research Group of Sustainable Energy, Air and Water Technology, Department of Bioscience Engineering, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerpen, Belgium.
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6
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Palomo A, Azevedo D, Touceda-Suárez M, Domingo-Félez C, Mutlu AG, Dechesne A, Wang Y, Zhang T, Smets BF. Efficient management of the nitritation-anammox microbiome through intermittent aeration: absence of the NOB guild and expansion and diversity of the NOx reducing guild suggests a highly reticulated nitrogen cycle. ENVIRONMENTAL MICROBIOME 2022; 17:39. [PMID: 35869541 PMCID: PMC9306079 DOI: 10.1186/s40793-022-00432-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Accepted: 06/26/2022] [Indexed: 06/15/2023]
Abstract
Obtaining efficient autotrophic ammonia removal (aka partial nitritation-anammox, or PNA) requires a balanced microbiome with abundant aerobic and anaerobic ammonia oxidizing bacteria and scarce nitrite oxidizing bacteria. Here, we analyzed the microbiome of an efficient PNA process that was obtained by sequential feeding and periodic aeration. The genomes of the dominant community members were inferred from metagenomes obtained over a 6 month period. Three Brocadia spp. genomes and three Nitrosomonas spp. genomes dominated the autotrophic community; no NOB genomes were retrieved. Two of the Brocadia spp. genomes lacked the genomic potential for nitrite reduction. A diverse set of heterotrophic genomes was retrieved, each with genomic potential for only a fraction of the denitrification pathway. A mutual dependency in amino acid and vitamin synthesis was noted between autotrophic and heterotrophic community members. Our analysis suggests a highly-reticulated nitrogen cycle in the examined PNA microbiome with nitric oxide exchange between the heterotrophs and the anammox guild.
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Affiliation(s)
- Alejandro Palomo
- Microbial Ecology and Technology Lab, Department of Environmental Engineering, Technical University of Denmark, Kgs Lyngby, Denmark
- School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong Province, China
| | - Daniela Azevedo
- Microbial Ecology and Technology Lab, Department of Environmental Engineering, Technical University of Denmark, Kgs Lyngby, Denmark
| | - María Touceda-Suárez
- Microbial Ecology and Technology Lab, Department of Environmental Engineering, Technical University of Denmark, Kgs Lyngby, Denmark
- Department of Environmental Science, University of Arizona, Tucson, AZ, USA
| | - Carlos Domingo-Félez
- Microbial Ecology and Technology Lab, Department of Environmental Engineering, Technical University of Denmark, Kgs Lyngby, Denmark
| | - A Gizem Mutlu
- Microbial Ecology and Technology Lab, Department of Environmental Engineering, Technical University of Denmark, Kgs Lyngby, Denmark
- Hydrotech - Veolia Water Technologies, Vellinge, Sweden
| | - Arnaud Dechesne
- Microbial Ecology and Technology Lab, Department of Environmental Engineering, Technical University of Denmark, Kgs Lyngby, Denmark
| | - Yulin Wang
- Environmental Microbiome Engineering and Biotechnology Laboratory, Department of Civil Engineering, The University of Hong Kong, Hong Kong SAR, People's Republic of China
| | - Tong Zhang
- Environmental Microbiome Engineering and Biotechnology Laboratory, Department of Civil Engineering, The University of Hong Kong, Hong Kong SAR, People's Republic of China
| | - Barth F Smets
- Microbial Ecology and Technology Lab, Department of Environmental Engineering, Technical University of Denmark, Kgs Lyngby, Denmark.
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7
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Kirim G, McCullough K, Bressani-Ribeiro T, Domingo-Félez C, Duan H, Al-Omari A, De Clippeleir H, Jimenez J, Klaus S, Ladipo-Obasa M, Mehrani MJ, Regmi P, Torfs E, Volcke EIP, Vanrolleghem PA. Mainstream short-cut N removal modelling: current status and perspectives. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2022; 85:2539-2564. [PMID: 35576252 DOI: 10.2166/wst.2022.131] [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
This work gives an overview of the state-of-the-art in modelling of short-cut processes for nitrogen removal in mainstream wastewater treatment and presents future perspectives for directing research efforts in line with the needs of practice. The modelling status for deammonification (i.e., anammox-based) and nitrite-shunt processes is presented with its challenges and limitations. The importance of mathematical models for considering N2O emissions in the design and operation of short-cut nitrogen removal processes is considered as well. Modelling goals and potential benefits are presented and the needs for new and more advanced approaches are identified. Overall, this contribution presents how existing and future mathematical models can accelerate successful full-scale mainstream short-cut nitrogen removal applications.
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Affiliation(s)
- Gamze Kirim
- modelEAU, Université Laval, 1065 avenue de la Médecine, Québec, QC G1 V 0A6, Canada E-mail: ; CentrEau, Quebec Water Research Centre, 1065 avenue de la Médecine, Québec, QC G1 V 0A6, Canada
| | - Kester McCullough
- School of Civil and Environmental Engineering, Cornell University, Ithaca, NY 14853, USA; Hampton Roads Sanitation District, 1434 Air Rail Ave., Virginia Beach, VA 23455, USA
| | - Thiago Bressani-Ribeiro
- BioCo Research Group, Department of Green Chemistry and Technology, Ghent University, Coupure Links 653, Gent 9000, Belgium
| | - Carlos Domingo-Félez
- Department of Environmental Engineering, Technical University of Denmark, Kongens Lyngby 2800, Denmark
| | - Haoran Duan
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Ahmed Al-Omari
- Brown and Caldwell, 1725 Duke St. Suite 250, Alexandria, VA 22314, USA
| | - Haydee De Clippeleir
- DC Water and Sewer Authority, 5000 Overlook Ave., SW., Washington, DC 20032, USA
| | - Jose Jimenez
- Brown and Caldwell, 1725 Duke St. Suite 250, Alexandria, VA 22314, USA
| | - Stephanie Klaus
- Hampton Roads Sanitation District, 1434 Air Rail Ave., Virginia Beach, VA 23455, USA
| | - Mojolaoluwa Ladipo-Obasa
- DC Water and Sewer Authority, 5000 Overlook Ave., SW., Washington, DC 20032, USA; Department of Civil & Environmental Engineering, The George Washington University, 800 22nd Street NW, Washington, DC 20037, USA
| | - Mohamad-Javad Mehrani
- Faculty of Civil and Environmental Engineering, Gdansk University of Technology, Ul. Narutowicza 11/12, Gdansk 80-233, Poland; Department of Urban Water and Waste Management, University of Duisburg-Essen, Universit¨atsstraße 15, 45141, Essen, Germany
| | - Pusker Regmi
- Brown and Caldwell, 1725 Duke St. Suite 250, Alexandria, VA 22314, USA
| | - Elena Torfs
- Centre for Advanced Process Technology for Urban Resource recovery (CAPTURE), Frieda Saeysstraat 1, Gent 9000, Belgium; BIOMATH, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, Gent 9000, Belgium
| | - Eveline I P Volcke
- BioCo Research Group, Department of Green Chemistry and Technology, Ghent University, Coupure Links 653, Gent 9000, Belgium; Centre for Advanced Process Technology for Urban Resource recovery (CAPTURE), Frieda Saeysstraat 1, Gent 9000, Belgium
| | - Peter A Vanrolleghem
- modelEAU, Université Laval, 1065 avenue de la Médecine, Québec, QC G1 V 0A6, Canada E-mail: ; CentrEau, Quebec Water Research Centre, 1065 avenue de la Médecine, Québec, QC G1 V 0A6, Canada
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8
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Wang S, Yu H, Su Q, Zuo J. Exploring the role of heterotrophs in partial nitritation-anammox process treating thermal hydrolysis process - anaerobic digestion reject water. BIORESOURCE TECHNOLOGY 2021; 341:125762. [PMID: 34450441 DOI: 10.1016/j.biortech.2021.125762] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 08/07/2021] [Accepted: 08/10/2021] [Indexed: 06/13/2023]
Abstract
Heterotrophic bacteria (HB) are generally prevalent in anammox-based processes, but their functional and ecological roles in partial nitritation-anammox (PN/A) process treating high-organics wastewater remained unclear. This study aimed to elucidate HB activities and microbial interactions in a one-stage PN/A treating thermal hydrolysis process (THP) - anaerobic digestion (AD) reject water. The PN/A reactor achieved a satisfactory nitrogen removal rate of 0.58 ± 0.06 g N/(L·d), and around 12% of COD in the THP-AD reject water was removed. N2O emission factors of the PN/A reactor were 1.15% ± 0.18% treating synthetic wastewater, and 0.95% ± 0.06% treating reject water. A balanced symbiotic relationship was maintained between HB and functional groups (i.e., anammox bacteria and aerobic-ammonia-oxidizing bacteria) over the reactor operation. The relative abundances of Anaerolineae spp. clearly increased, while Denitratisoma, capable of denitrification, slightly decreased when treating THP-AD reject water. The preference for electron donors of heterotrophs explained discrepant growth trends.
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Affiliation(s)
- Sike Wang
- Department of Material and Environmental Engineering, Shenzhen Polytechnic, Shenzhen 518055, China; State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Heng Yu
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; College of Chemistry and Chemical Engineering, Xi'an Shiyou University, Xi'an, Shaanxi Province 710065, China
| | - Qingxian Su
- Department of Environmental Engineering, Technical University of Denmark, Kgs., Lyngby 2800, Denmark
| | - Jiane Zuo
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China.
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9
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Wan X, Laureni M, Jia M, Volcke EIP. Impact of organics, aeration and flocs on N 2O emissions during granular-based partial nitritation-anammox. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 797:149092. [PMID: 34303231 PMCID: PMC7612980 DOI: 10.1016/j.scitotenv.2021.149092] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 07/11/2021] [Accepted: 07/13/2021] [Indexed: 05/21/2023]
Abstract
Partial nitration-anammox is a resource-efficient technology for nitrogen removal from wastewater. However, the advantages of this nitrogen removal technology are challenged by the emission of N2O, a potent greenhouse gas. In this study, a granular sludge one-stage partial nitritation-anammox reactor comprising granules and flocs was run for 337 days in the presence of influent organics to investigate its effect on N removal and N2O emissions. Besides, the effect of aeration control strategies and flocs removal was investigated as well. The interpretation of the experimental results was complemented with modelling and simulation. The presence of influent organics (1 g COD g-1 N) helped to suppress NOB and significantly reduced the overall N2O emissions while having no significant effect on anammox activity. Besides, long-term monitoring of the reactor indicated that constant airflow rate control resulted in more stable effluent quality and less N2O emissions than DO control. Still, floc removal reduced N2O emissions at DO control but increased N2O emissions at constant airflow rate. Furthermore, anammox bacteria could significantly reduce N2O production during heterotrophic denitrification, likely via competition for NO with heterotrophs. Overall, this study demonstrated that the presence of influent organics together with proper aeration control strategies and floc management could significantly reduce the N2O emissions without compromising nitrogen removal efficiency during one-stage partial nitritation-anammox processes.
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Affiliation(s)
- Xinyu Wan
- BioCo Research Group, Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000, Ghent, Belgium
| | - Michele Laureni
- BioCo Research Group, Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000, Ghent, Belgium; Department of Biotechnology, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, Delft 2629 HZ, the Netherlands
| | - Mingsheng Jia
- BioCo Research Group, Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000, Ghent, Belgium
| | - Eveline I P Volcke
- BioCo Research Group, Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000, Ghent, Belgium.
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10
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Pereira TDS, Spindola RH, Rabelo CABS, Silveira NC, Adorno MAT, Kunz A, Pires EC, Damianovic MHRZ. A predictive model for N 2O production in anammox-granular sludge reactors: Combined effects of nitrite/ammonium ratio and organic matter concentration. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 297:113295. [PMID: 34311258 DOI: 10.1016/j.jenvman.2021.113295] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 06/29/2021] [Accepted: 07/12/2021] [Indexed: 06/13/2023]
Abstract
Once the use of anammox reactors has been increasing on a global scale, it is important to understand the mechanisms of N2O emissions and how to minimise the emissions by optimising the operating conditions. In this study, the influence of chemical oxygen demand (COD) (from 0 mgO2 L-1 to 100 mgO2 L-1) and nitrite/ammonium ratio from 0.79 to 2.21 (maintaining ammonium at 100 mgN L-1 and varying nitrite from 79 mgN L-1 to 221 mgN L-1) in the N2O emissions from anammox-granular sludge reactor was investigated in two steps. Step 1 consisted of batch tests, using central composite design, and Step 2, long-term operation of a 6.5 L continuous up-flow reactor. The results showed that the N2O emissions were minimized by controlling, in the influent, the NO2--N/NH4+-N ratio from 1.1 to 1.3 and maintaining the COD concentration below 100 mgO2 L-1. TN removal efficiencies were higher than 70% in all conditions tested".
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Affiliation(s)
- T D S Pereira
- Laboratory of Biological Processes, Department of Hydraulics and Sanitation, São Carlos School of Engineering, University of São Paulo, Av. João Dagnone, 1100, Jd. Santa Angelina, 13563-120, São Carlos, SP, Brazil.
| | - R H Spindola
- Laboratory of Biological Processes, Department of Hydraulics and Sanitation, São Carlos School of Engineering, University of São Paulo, Av. João Dagnone, 1100, Jd. Santa Angelina, 13563-120, São Carlos, SP, Brazil
| | - C A B S Rabelo
- Laboratory of Biological Processes, Department of Hydraulics and Sanitation, São Carlos School of Engineering, University of São Paulo, Av. João Dagnone, 1100, Jd. Santa Angelina, 13563-120, São Carlos, SP, Brazil
| | - N C Silveira
- Laboratory of Biological Processes, Department of Hydraulics and Sanitation, São Carlos School of Engineering, University of São Paulo, Av. João Dagnone, 1100, Jd. Santa Angelina, 13563-120, São Carlos, SP, Brazil
| | - M A T Adorno
- Laboratory of Biological Processes, Department of Hydraulics and Sanitation, São Carlos School of Engineering, University of São Paulo, Av. João Dagnone, 1100, Jd. Santa Angelina, 13563-120, São Carlos, SP, Brazil
| | - A Kunz
- Embrapa Suínos e Aves, 89715-899, Concórdia, SC, Brazil
| | - E C Pires
- Laboratory of Biological Processes, Department of Hydraulics and Sanitation, São Carlos School of Engineering, University of São Paulo, Av. João Dagnone, 1100, Jd. Santa Angelina, 13563-120, São Carlos, SP, Brazil
| | - M H R Z Damianovic
- Laboratory of Biological Processes, Department of Hydraulics and Sanitation, São Carlos School of Engineering, University of São Paulo, Av. João Dagnone, 1100, Jd. Santa Angelina, 13563-120, São Carlos, SP, Brazil
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11
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Wan X, Baeten JE, Laureni M, Volcke EIP. Ammonium-based aeration control improves nitrogen removal efficiency and reduces N 2O emissions for partial nitritation-anammox reactors. CHEMOSPHERE 2021; 274:129720. [PMID: 33548645 PMCID: PMC7612981 DOI: 10.1016/j.chemosphere.2021.129720] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 12/27/2020] [Accepted: 01/17/2021] [Indexed: 05/30/2023]
Abstract
This study deals with the effect of aeration control strategies on the nitrogen removal efficiency and nitrous oxide (N2O) emissions in a partial nitritation-anammox reactor with granular sludge. More specifically, dissolved oxygen (DO) control, constant airflow and effluent ammonium (NH4+) control strategies were compared through a simulation study. Particular attention was paid to the effect of flocs, which are deliberately or unavoidable present besides granules in this type of reactor. When applying DO control, DO setpoints had to be adjusted to the amount of flocs present in the reactor to maintain high nitrogen removal and reduce N2O emissions, which is difficult to realize in practice because of variable floc fractions. Constant airflow rate control could maintain a good nitrogen removal efficiency independent of the floc fraction in the reactor, but failed in N2O mitigation. Controlling aeration based on the effluent ammonium concentration results in both high nitrogen removal and relatively low N2O emissions, also in the presence of flocs. Fluctuations in floc fractions caused significant upsets in nitrogen removal and N2O emissions under DO control but had less effect at constant airflow and effluent ammonium control. Still, rapid and sharp drops in flocs led to a peak in N2O emissions at constant airflow and effluent ammonium control. Overall, effluent ammonium control reached the highest average nitrogen removal and lowest N2O emissions and consumed the lowest aeration energy under fluctuating floc concentrations.
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Affiliation(s)
- Xinyu Wan
- BioCo Research Group, Department of Green Chemistry and Technology, Ghent University, Coupure Links 653, Ghent, 9000, Belgium
| | - Janis E Baeten
- BioCo Research Group, Department of Green Chemistry and Technology, Ghent University, Coupure Links 653, Ghent, 9000, Belgium
| | - Michele Laureni
- BioCo Research Group, Department of Green Chemistry and Technology, Ghent University, Coupure Links 653, Ghent, 9000, Belgium; Environmental Biotechnology Group, Delft University of Technology, Mekelweg 5, Delft, CD, 2628, Netherlands
| | - Eveline I P Volcke
- BioCo Research Group, Department of Green Chemistry and Technology, Ghent University, Coupure Links 653, Ghent, 9000, Belgium.
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12
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Duan H, Zhao Y, Koch K, Wells GF, Zheng M, Yuan Z, Ye L. Insights into Nitrous Oxide Mitigation Strategies in Wastewater Treatment and Challenges for Wider Implementation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:7208-7224. [PMID: 33975433 DOI: 10.1021/acs.est.1c00840] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Nitrous oxide (N2O) emissions account for the majority of the carbon footprint of wastewater treatment plants (WWTPs). Many N2O mitigation strategies have since been developed while a holistic view is still missing. This article reviews the state-of-the-art of N2O mitigation studies in wastewater treatment. Through analyzing existing studies, this article presents the essential knowledge to guide N2O mitigations, and the logics behind mitigation strategies. In practice, mitigations are mainly carried out by aeration control, feed scheme optimization, and process optimization. Despite increasingly more studies, real implementation remains rare, which is a combined result of unclear climate change policies/incentives, as well as technical challenges. Five critical technical challenges, as well as opportunities, of N2O mitigations were identified. It is proposed that (i) quantification methods for overall N2O emissions and pathway contributions need improvement; (ii) a reliable while straightforward mathematical model is required to quantify benefits and compare mitigation strategies; (iii) tailored risk assessment needs to be conducted for WWTPs, in which more long-term full-scale trials of N2O mitigation are urgently needed to enable robust assessments of the resulting operational costs and impact on nutrient removal performance; (iv) current mitigation strategies focus on centralized WWTPs, more investigations are warranted for decentralised systems, especially decentralized activated sludge WWTPs; and (v) N2O may be mitigated by adopting novel strategies promoting N2O reduction denitrification or microorganisms that emit less N2O. Overall, we conclude N2O mitigation research is reaching a maturity while challenges still exist for a wider implementation, especially in relation to the reliability of N2O mitigation strategies and potential risks to nutrient removal performances of WWTPs.
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Affiliation(s)
- Haoran Duan
- School of Chemical Engineering, the University of Queensland, St. Lucia, Queensland 4072, Australia
- Advanced Water Management Centre (AWMC), the University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Yingfen Zhao
- School of Chemical Engineering, the University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Konrad Koch
- Chair of Urban Water Systems Engineering, Technical University of Munich, Am Coulombwall 3, 85748 Garching, Germany
| | - George F Wells
- Department of Civil and Environmental Engineering, Northwestern University, Evanston, Illinois 60208, United States
| | - Min Zheng
- Advanced Water Management Centre (AWMC), the University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Zhiguo Yuan
- Advanced Water Management Centre (AWMC), the University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Liu Ye
- School of Chemical Engineering, the University of Queensland, St. Lucia, Queensland 4072, Australia
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13
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Myers S, Mikola A, Blomberg K, Kuokkanen A, Rosso D. Comparison of methods for nitrous oxide emission estimation in full-scale activated sludge. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2021; 83:641-651. [PMID: 33600368 DOI: 10.2166/wst.2021.033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Nitrous oxide (N2O) gas transfer was studied in a full-scale process to correlate liquid phase N2O concentrations with gas phase N2O emissions and compare methods of determining the volumetric mass transfer coefficient, KLa. Off-gas and liquid phase monitoring were conducted at the Viikinmäki wastewater treatment plant (WWTP) over a two-week period using a novel method for simultaneous measurement of dissolved and off-gas N2O and O2 from the same location. KLa was calculated with three methods: empirically, based on aeration superficial velocity, from experimentally determined O2 KLa, and using a static value of best fit. The findings of this study indicated trends in local emitted N2O consistently matched trends in local dissolved N2O, but the magnitude of N2O emissions could not be accurately estimated without correction. After applying a static correction factor, the O2 method, using experimentally determined O2 KLa, provided the best N2O emission estimation over the data collection period. N2O emissions estimated using the O2 method had a root mean square error (RMSE) of 70.5 compared against measured concentrations ranging from 3 to 1,913 ppm and a maximum 28% error. The KLa value, and therefore the method of KLa determination, had a significant impact on estimated emissions.
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Affiliation(s)
- Shanna Myers
- Aalto University and Murraysmith, 888 SW 5th Avenue, Suite #1170, Portland, OR 97204, USA E-mail:
| | - Anna Mikola
- Aalto University, P.O. Box 11000, FI-00076 Aalto, Espoo, Finland
| | - Kati Blomberg
- Helsinki Region Environmental Services Authority (HSY), P.O. Box 100, FI-00066 HSY, Helsinki, Finland
| | - Anna Kuokkanen
- Helsinki Region Environmental Services Authority (HSY), P.O. Box 100, FI-00066 HSY, Helsinki, Finland
| | - Diego Rosso
- University of California, Irvine, CA 92697, USA
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14
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Yuan H, Huang S, Yuan J, You Y, Zhang Y. Characteristics of microbial denitrification under different aeration intensities: Performance, mechanism, and co-occurrence network. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 754:141965. [PMID: 32911146 DOI: 10.1016/j.scitotenv.2020.141965] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 08/09/2020] [Accepted: 08/23/2020] [Indexed: 06/11/2023]
Abstract
This study aimed to explore how dissolved oxygen (DO) affected the characteristics and mechanisms of denitrification in mixed bacterial consortia. We analyzed denitrification efficiency, intracellular nicotinamide adenine dinucleotide (NADH), relative expression of functional genes, and potential co-occurrence network of microorganisms. Results showed that the total nitrogen (TN) removal rates at different aeration intensities (0.00, 0.25, 0.63, and 1.25 L/(L·min)) were 0.93, 1.45, 0.86, and 0.53 mg/(L·min), respectively, which were higher than previously reported values for pure culture. The optimal aeration intensity was 0.25 L/(L·min), at which the maximum NADH accumulation rate and highest relative abundance of napA, nirK, and nosZ were achieved. With increased aeration intensity, the amount of electron flux to nitrate decreased and nitrate assimilation increased. On one hand, nitrate reduction was primarily inhibited by oxygen through competition for electron donors of a certain single strain. On the other hand, oxygen was consumed rapidly by bacteria by stimulating carbon metabolism to create an optimal denitrification niche for denitrifying microorganisms. Denitrification was performed via inter-genus cooperation (competitive interactions and symbiotic relationships) between keystone taxa (Azoarcus, Paracoccus, Thauera, Stappia, and Pseudomonas) and other heterotrophic bacteria (OHB) in aeration reactors. However, in the non-aeration case, which was primarily carried out based on intra-genus syntrophy within genus Propionivibrio, the co-occurrence network constructed the optimal niche contributing to the high TN removal efficiency. Overall, this study enhanced our knowledge about the molecular ecological mechanisms of aerobic denitrification in mixed bacterial consortia and has theoretical guiding significance for further practical application.
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Affiliation(s)
- Haiguang Yuan
- School of Environment and Energy, South China University of Technology, Higher Education Mega Center, Guangzhou 510006, PR China; Guangdong Ecological Environment Control Engineering Technology Research Center, South China University of Technology, Higher Education Mega Center, Guangzhou 510006, PR China
| | - Shaobin Huang
- School of Environment and Energy, South China University of Technology, Higher Education Mega Center, Guangzhou 510006, PR China; Guangdong Ecological Environment Control Engineering Technology Research Center, South China University of Technology, Higher Education Mega Center, Guangzhou 510006, PR China; State Key Laboratory of Pulp and Paper Engineering, Plant Micro/Nano Fiber Research Center, South China University of Technology, Guangzhou 510640, PR China.
| | - Jianqi Yuan
- School of Environment and Energy, South China University of Technology, Higher Education Mega Center, Guangzhou 510006, PR China; Guangdong Ecological Environment Control Engineering Technology Research Center, South China University of Technology, Higher Education Mega Center, Guangzhou 510006, PR China
| | - Yingying You
- School of Environment and Energy, South China University of Technology, Higher Education Mega Center, Guangzhou 510006, PR China; Guangdong Ecological Environment Control Engineering Technology Research Center, South China University of Technology, Higher Education Mega Center, Guangzhou 510006, PR China
| | - Yongqing Zhang
- School of Environment and Energy, South China University of Technology, Higher Education Mega Center, Guangzhou 510006, PR China
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Al-Hazmi HE, Lu X, Majtacz J, Kowal P, Xie L, Makinia J. Optimization of the Aeration Strategies in a Deammonification Sequencing Batch Reactor for Efficient Nitrogen Removal and Mitigation of N 2O Production. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:1218-1230. [PMID: 33378162 DOI: 10.1021/acs.est.0c04229] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
In deammonification systems, nitrite-oxidizing bacteria (NOB) suppression and nitrous oxide (N2O) mitigation are two important operational objectives. To carry out this multivariable analysis of response, a comprehensive model for the N cycle was developed and evaluated against experimental data from a laboratory-scale deammonification granular sludge sequencing batch reactor. Different aeration strategies were tested, and the manipulated variables comprised the dissolved oxygen (DO) set point in the aerated phase, aeration on/off frequency (F), and the ratio (R) between the non-aerated and aerated phase durations. Experimental results showed that a high ammonium utilization rate (AUR) in relation to the low nitrate production rate (NPR) (NPR/AUR = 0.07-0.08) and limited N2O emissions (EN2O < 2%) could be achieved at the DO set point = 0.7 mg O2/L, R ratio = 2, and F frequency = 6-7 h-1. Under specific operational conditions (biomass concentration, NH4+-N loading rate, and temperature), simulation results confirmed the feasible aeration strategies for the trade-offs between the NOB suppression and N2O emission. The intermittent aeration regimes led to frequent shifts in the predominating N2O production pathways, that is, hydroxylamine (NH2OH) oxidation (aerated phase) versus autotrophic denitrification (non-aerated phase). The inclusion of the extracellular polymeric substance mechanism in the model explained the observed activity of heterotrophs, especially Anaerolineae, and granule formation.
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Affiliation(s)
- Hussein E Al-Hazmi
- Faculty of Civil and Environmental Engineering, Gdansk University of Technology, ul. Narutowicza 11/12, 80-233 Gdansk, Poland
| | - Xi Lu
- Faculty of Civil and Environmental Engineering, Gdansk University of Technology, ul. Narutowicza 11/12, 80-233 Gdansk, Poland
- Institute of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China
| | - Joanna Majtacz
- Faculty of Civil and Environmental Engineering, Gdansk University of Technology, ul. Narutowicza 11/12, 80-233 Gdansk, Poland
| | - Przemyslaw Kowal
- Faculty of Civil and Environmental Engineering, Gdansk University of Technology, ul. Narutowicza 11/12, 80-233 Gdansk, Poland
| | - Li Xie
- Institute of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China
| | - Jacek Makinia
- Faculty of Civil and Environmental Engineering, Gdansk University of Technology, ul. Narutowicza 11/12, 80-233 Gdansk, Poland
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16
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Xiao P, Ai S, Zhou J, Luo X, Kang B, Feng L, Zhao T. N 2O profiles in the enhanced CANON process via long-term N 2H 4 addition: minimized N 2O production and the influence of exogenous N 2H 4 on N 2O sources. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:37188-37198. [PMID: 31748991 DOI: 10.1007/s11356-019-06508-w] [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: 07/14/2019] [Accepted: 09/10/2019] [Indexed: 06/10/2023]
Abstract
Production of the greenhouse gas nitrous oxide (N2O) from the completely autotrophic nitrogen removal over nitrite (CANON) process is of growing concern. In this study, the effect of added hydrazine (N2H4) on N2O production during the CANON process was investigated. Long-term trace N2H4 addition minimized N2O production (0.018% ± 0.013% per unit total nitrogen removed) and maintaining high nitrogen removal capacity of CANON process (nitrogen removal rate and TN removal efficiency was 450 ± 60 mg N/L/day and 71 ± 8%, respectively). Ammonium oxidizing bacteria (AOB) was the main N2O producer. AOB activity inhibition by N2H4 decreased N2O production during aeration, and the N2H4 concentration was negatively correlated with N2O production rate in NH4+ oxidation via AOB, whereas N2O production was facilitated under anaerobic conditions because hydroxylamine (NH2OH) production was accelerated due to anammox bacteria (AnAOB) activity strengthen via N2H4. Added N2H4 completely degraded in the initial aeration phases of the CANON SBR, during which some N2H4 intensified anammox for total nitrogen removal to eliminate N2O production from nitrifier denitrification (ND) by anammox-associated, while the remaining N2H4 competed with NH2OH for hydroxylamine oxidoreductase (HAO) in AOB to inhibit intermediates formation that result in N2O production via NH2OH oxidation (HO) pathway, consequently decreasing total N2O production.
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Affiliation(s)
- Pengying Xiao
- College of Chemistry and Chemical Engineering, Chongqing University of Technology, No. 69 Hongguang Avenue, Chongqing, 400054, Banan District, People's Republic of China.
| | - Shuo Ai
- College of Chemistry and Chemical Engineering, Chongqing University of Technology, No. 69 Hongguang Avenue, Chongqing, 400054, Banan District, People's Republic of China
| | - Jing Zhou
- College of Chemistry and Chemical Engineering, Chongqing University of Technology, No. 69 Hongguang Avenue, Chongqing, 400054, Banan District, People's Republic of China
| | - Xiaojing Luo
- College of Chemistry and Chemical Engineering, Chongqing University of Technology, No. 69 Hongguang Avenue, Chongqing, 400054, Banan District, People's Republic of China
| | - Baowen Kang
- College of Chemistry and Chemical Engineering, Chongqing University of Technology, No. 69 Hongguang Avenue, Chongqing, 400054, Banan District, People's Republic of China
| | - Li Feng
- Chongqing Academy of Environmental Science, Chongqing, 400054, People's Republic of China
| | - Tiantao Zhao
- College of Chemistry and Chemical Engineering, Chongqing University of Technology, No. 69 Hongguang Avenue, Chongqing, 400054, Banan District, People's Republic of China.
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17
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Chen H, Zeng L, Wang D, Zhou Y, Yang X. Recent advances in nitrous oxide production and mitigation in wastewater treatment. WATER RESEARCH 2020; 184:116168. [PMID: 32683143 DOI: 10.1016/j.watres.2020.116168] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 06/17/2020] [Accepted: 07/10/2020] [Indexed: 05/21/2023]
Abstract
Nitrous oxide (N2O) emitted from wastewater treatment plants has caused widespread concern. Over the past decade, people have made tremendous efforts to discover the microorganisms responsible for N2O production, elucidate metabolic pathways, establish production models and formulate mitigation strategies. The ultimate goal of all these efforts is to shed new light on how N2O is produced and how to reduce it, and one of the best ways is to find key opportunities by integrating the information obtained. This review article critically evaluates the knowledge gained in the field within a decade, especially in N2O production microbiology, biochemistry, models and mitigation strategies, with a focus on denitrification. Previous research has greatly deepened the understanding of the N2O generation mechanism, but further efforts are still needed due to the lack of standardized methodology for establishing N2O mitigation strategies in full-scale systems. One of the challenges seems to be to convert the denitrification process from a net N2O source into an effective sink, which is recommended as a key opportunity to reduce N2O production in this review.
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Affiliation(s)
- Hongbo Chen
- College of Environment and Resources, Xiangtan University, Xiangtan 411105, China.
| | - Long Zeng
- College of Environment and Resources, Xiangtan University, Xiangtan 411105, China
| | - Dongbo Wang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China.
| | - Yaoyu Zhou
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong, China
| | - Xiao Yang
- Korea Biochar Research Center, O-Jeong Eco-Resilience Institute & Division of Environmental Science and Ecological Engineering, Korea University, Seoul 02841, South Korea
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18
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Chen X, Yang L, Sun J, Wei W, Liu Y, Ni BJ. Influences of Longitudinal Heterogeneity on Nitrous Oxide Production from Membrane-Aerated Biofilm Reactor: A Modeling Perspective. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:10964-10973. [PMID: 32786580 DOI: 10.1021/acs.est.0c04067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
As a promising technology for sustainable nitrogen removal from wastewater, the membrane-aerated biofilm reactors (MABRs) performing autotrophic deammonification are faced with the problem of unwanted production of nitrous oxide (N2O, a potent greenhouse gas). As a common tool to study N2O production from such an MABR, the traditional one-dimensional modeling approach fails to simulate the existence of longitudinal gradients in the reactor and therefore might render N2O production significantly deviated from reality. To this end, this work aims to study the influences of key longitudinal gradients (i.e., in oxygen, liquid-phase components, and biofilm thickness) on the N2O production from a typical MABR performing autotrophic deammonification by applying a modified version of a newly developed compartmental model. Through comparing the modeling results of different reactor configurations, this work reveals that the single impact of the longitudinal gradients studied on the N2O production from the MABR follows the order: oxygen (significant) > liquid-phase components (slight) > biofilm thickness (almost none). When multiple longitudinal gradients are present, they become correlated and would jointly influence the N2O production and nitrogen removal of the MABR. The results also show the need for multispot measurements to get an accurate representation of spatial biofilm features of the MABR configuration with the membrane lumen designed/operated as a plug flow reactor. While the traditional modeling approach is acceptable to evaluate the nitrogen removal in most cases, it might overestimate or underestimate the N2O production from the MABR with at least one of the longitudinal gradients in oxygen and liquid-phase components. For such an MABR, the longitudinal heterogeneity in biofilm thickness and the number of biofilm thickness classes to be included in the model would also make a difference to the simulation results, especially the N2O production. The work also proposes that under the studied conditions, proper design/operation of the MABR in consideration of longitudinal heterogeneity has the theoretical potential of reducing the N2O production by 77% without significantly compromising the nitrogen removal.
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Affiliation(s)
- Xueming Chen
- College of Environment and Resources, Fuzhou University, Fujian 350116, China
| | - Linyan Yang
- School of Resources and Environmental Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Jing Sun
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Wei Wei
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW 2007, Australia
| | - Yiwen Liu
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW 2007, Australia
| | - Bing-Jie Ni
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW 2007, Australia
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Liu Y, Zhao T, Su Z, Zhu T, Ni BJ. Evaluating the roles of coexistence of sludge flocs on nitrogen removal and nitrous oxide production in a granule-based autotrophic nitrogen removal system. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 730:139018. [PMID: 32413601 DOI: 10.1016/j.scitotenv.2020.139018] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 04/24/2020] [Accepted: 04/24/2020] [Indexed: 06/11/2023]
Abstract
Certain levels of sludge flocs would always coexist in granule-based reactors due to the biomass detachment from granules. Such inevitable coexistence could affect both total nitrogen (TN) removal and nitrous oxide (N2O) production in autotrophic nitrogen removal systems. This work utilized a mathematical approach to systematically study the influence of the coexisting sludge flocs on TN removal and N2O production in a granular nitritation-anaerobic ammonium oxidation (Anammox) process for the first time, based on a 2-pathway N2O production model concept. The modelling results reveal that the highest TN removal efficiency decreases from ca. 87-88% to ca. 41-49% as the fraction of sludge flocs in the system increases from 10% to 40%, while the N2O production rate gradually increases with such increase. Meanwhile, both bulk dissolved oxygen (DO, 0.05-0.3 mg/L) and the size of granule (200-400 μm) could also influence the TN removal efficiency and N2O production. As the fraction of sludge flocs increases from 10% to 40%, the contribution of granular biomass to total N2O production is reduced due to increase of N2O-producing ammonia-oxidizing bacteria (AOB) in the sludge flocs, and the increase of granule size could intensify such decrease. In addition, the hydroxylamine oxidation pathway dominates the nitrifier denitrification pathway in both granules and sludge flocs under various testing conditions, whereas the increasing contribution of the latter would occur at a certain DO range, higher fraction of sludge flocs and smaller granule size. These results disclose an important influence of the coexisting sludge flocs on the performance of granular nitritation-Anammox systems.
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Affiliation(s)
- Yiwen Liu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China; Academy of Environment and Ecology, Tianjin University, Tianjin 300072, China
| | - Tianhang Zhao
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Zhongxian Su
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Tingting Zhu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Bing-Jie Ni
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
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Fang F, Li H, Jiang X, Deng X, Yan P, Guo J, Chen Y, Yang J. Significant N 2O emission from a high rate granular reactor for completely autotrophic nitrogen removal over nitrite. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2020; 266:110586. [PMID: 32392139 DOI: 10.1016/j.jenvman.2020.110586] [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: 01/20/2020] [Revised: 03/29/2020] [Accepted: 04/07/2020] [Indexed: 06/11/2023]
Abstract
Expanded granular sludge bed (EGSB) reactors were rarely applied for complete ammonium removal over nitrite. In this study, a high ammonium loading rate of 3677 mg N/L/d was achieved in an EGSB reactor. Approximately 5.5-8.5% of influent ammonium was converted to nitrous oxide (N2O) that is a potent greenhouse gas. Moreover, the percentage increased linearly with the increase in ammonium load. A model well matched the reactor dynamics. The model indicated that hydroxylamine (NH2OH) oxidation contributed to over 40% of produced N2O, and denitrification by ammonium oxidizing bacteria contributed to N2O emission significantly. Furthermore, the model suggests that a low oxygen concentration can result in a low N2O emission at the cost of a slightly low ammonium removal rate while influent organic matter play a minor role in reducing N2O emission. This study shows that EGSB reactors are effective in ammonium removal. In addition, the emission of N2O is significant.
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Affiliation(s)
- Fang Fang
- College of Environment and Ecology, Chongqing University, Chongqing, China.
| | - Hanxiang Li
- College of Environment and Ecology, Chongqing University, Chongqing, China
| | - Xin Jiang
- College of Environment and Ecology, Chongqing University, Chongqing, China
| | - Xiongwen Deng
- College of Environment and Ecology, Chongqing University, Chongqing, China
| | - Peng Yan
- College of Environment and Ecology, Chongqing University, Chongqing, China
| | - Jinsong Guo
- College of Environment and Ecology, Chongqing University, Chongqing, China
| | - Youpeng Chen
- College of Environment and Ecology, Chongqing University, Chongqing, China
| | - Jixiang Yang
- College of Environment and Ecology, Chongqing University, Chongqing, China; Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, China.
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21
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Vasilaki V, Conca V, Frison N, Eusebi AL, Fatone F, Katsou E. A knowledge discovery framework to predict the N 2O emissions in the wastewater sector. WATER RESEARCH 2020; 178:115799. [PMID: 32361289 DOI: 10.1016/j.watres.2020.115799] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 03/04/2020] [Accepted: 04/03/2020] [Indexed: 06/11/2023]
Abstract
Data Analytics is being deployed to predict the dissolved nitrous oxide (N2O) concentration in a full-scale sidestream sequence batch reactor (SBR) treating the anaerobic supernatant. On average, the N2O emissions are equal to 7.6% of the NH4-N load and can contribute up to 97% to the operational carbon footprint of the studied nitritation-denitritation and via-nitrite enhanced biological phosphorus removal process (SCENA). The analysis showed that average aerobic dissolved N2O concentration could significantly vary under similar influent loads, dissolved oxygen (DO), pH and removal efficiencies. A combination of density-based clustering, support vector machine (SVM), and support vector regression (SVR) models were deployed to estimate the dissolved N2O concentration and behaviour in the different phases of the SBR system. The results of the study reveal that the aerobic dissolved N2O concentration is correlated with the drop of average aerobic conductivity rate (spearman correlation coefficient equal to 0.7), the DO (spearman correlation coefficient equal to -0.7) and the changes of conductivity between sequential cycles. Additionally, operational conditions resulting in low aerobic N2O accumulation (<0.6 mg/L) were identified; step-feeding, control of initial NH4+ concentrations and aeration duration can mitigate the N2O peaks observed in the system. The N2O emissions during aeration shows correlation with the stripping of accumulated N2O from the previous anoxic cycle. The analysis shows that N2O is always consumed after the depletion of NO2- during denitritation (after the "nitrite knee"). Based on these findings SVM classifiers were constructed to predict whether dissolved N2O will be consumed during the anoxic and anaerobic phases and SVR models were trained to predict the N2O concentration at the end of the anaerobic phase and the average dissolved N2O concentration during aeration. The proposed approach accurately predicts the N2O emissions as a latent parameter from other low-cost sensors that are traditionally deployed in biological batch processes.
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Affiliation(s)
- V Vasilaki
- Department of Civil & Environmental Engineering, Brunel University London, Uxbridge, UB8 3PH, UK
| | - V Conca
- Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134, Verona, Italy
| | - N Frison
- Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134, Verona, Italy
| | - A L Eusebi
- Department SIMAU, Faculty of Engineering, Polytechnic University of Marche, Via Brecce Bianche 12, Ancona, Italy
| | - F Fatone
- Department SIMAU, Faculty of Engineering, Polytechnic University of Marche, Via Brecce Bianche 12, Ancona, Italy
| | - E Katsou
- Department of Civil & Environmental Engineering, Brunel University London, Uxbridge, UB8 3PH, UK.
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Magwaza ST, Magwaza LS, Odindo AO, Mditshwa A. Hydroponic technology as decentralised system for domestic wastewater treatment and vegetable production in urban agriculture: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 698:134154. [PMID: 31505342 DOI: 10.1016/j.scitotenv.2019.134154] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 08/22/2019] [Accepted: 08/26/2019] [Indexed: 06/10/2023]
Abstract
Water scarcity, nutrient-depleted soils and pollution continue to be a major challenge worldwide and these are likely to worsen with increasing global populations particularly, in urban areas. As a result, environmental and public health problems may arise from the insufficient provision of sanitation and wastewater disposal facilities. Because of this, a paradigm shifts with regard to the sustainable management of waste disposal in a manner that could protect the environment at the same time benefits society by allowing nutrient recovery and reuse for food production is required. Hence, the use of urban wastewater for agricultural irrigation has more potential, especially when incorporating the reuse of nutrients like nitrogen and phosphorous, which are essential for crop production. Among the current treatment technologies applied in urban wastewater reuse for agriculture, hydroponic system is identified as one of the alternative technology that can be integrated with wastewater treatment. The integration of hydroponic system with municipal wastewater treatment has the advantage of reducing costs in terms of pollutants removal while reducing maintenance and energy costs required for conventional wastewater treatment. The efficiency of a hydroponic system with regard to municipal wastewater reuse is mainly linked to its capacity to allow continuous use of wastewater through the production of agricultural crops and the removal of pollutants/nutrients (nitrogen and phosphorus), resulting to increased food security and environmental protection. Moreover, the suitability of hydroponic system for wastewater treatment is derived from its capacity to minimize associated health risks to farmers, harvested crop and consumers, that may arise through contact with wastewater.
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Affiliation(s)
- Shirly Tentile Magwaza
- Discipline of Crop and Horticultural Sciences, School of Agricultural, Earth and Environmental Science, University of KwaZulu-Natal, Private Bag X01, Scottsville, 3209 Pietermaritzburg, South Africa
| | - Lembe Samukelo Magwaza
- Discipline of Crop and Horticultural Sciences, School of Agricultural, Earth and Environmental Science, University of KwaZulu-Natal, Private Bag X01, Scottsville, 3209 Pietermaritzburg, South Africa.
| | - Alfred Oduor Odindo
- Discipline of Crop and Horticultural Sciences, School of Agricultural, Earth and Environmental Science, University of KwaZulu-Natal, Private Bag X01, Scottsville, 3209 Pietermaritzburg, South Africa
| | - Asanda Mditshwa
- Discipline of Crop and Horticultural Sciences, School of Agricultural, Earth and Environmental Science, University of KwaZulu-Natal, Private Bag X01, Scottsville, 3209 Pietermaritzburg, South Africa
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Liu T, Hu S, Yuan Z, Guo J. High-level nitrogen removal by simultaneous partial nitritation, anammox and nitrite/nitrate-dependent anaerobic methane oxidation. WATER RESEARCH 2019; 166:115057. [PMID: 31520813 DOI: 10.1016/j.watres.2019.115057] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 09/03/2019] [Accepted: 09/04/2019] [Indexed: 06/10/2023]
Abstract
While the anaerobic ammonium oxidation (anammox) process has been applied for nitrogen removal from high-strength wastewater, nitrate accumulation in effluent still represents a major concern. Here, a novel process, named the one-stage PNAM, that integrates the Partial Nitritation (PN), Anammox and Methane-dependent nitrite/nitrate reduction reactions in a single membrane biofilm reactor (MBfR) is developed. With feeding of 1030 mg NH4+-N/L at a hydraulic retention time of 16 h, the proposed one-stage PNAM process achieved an average total nitrogen removal efficiency of 98% and a nitrogen removal rate of 1.5 kg N/m3/d (1.4-1.8 g N/m2/d) by using methane as the sole carbon-based electron donor. The N2O emission was determined to be 0.34% ± 0.01%. Microbial community characterization revealed that ammonia-oxidizing bacteria (AOB), anammox bacteria, nitrite/nitrate-dependent anaerobic methane oxidation (n-DAMO) bacteria and archaea co-developed in the biofilm. Batch tests showed that AOB, anammox bacteria and n-DAMO microorganisms were indeed jointly responsible for the nitrogen removal. This one-stage PNAM process can potentially be applied to treating high-strength wastewater, such as anaerobic sludge digestion liquor or landfill leachate.
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Affiliation(s)
- Tao Liu
- Advanced Water Management Centre, The University of Queensland, St. Lucia, Queensland, 4072, Australia
| | - Shihu Hu
- Advanced Water Management Centre, The University of Queensland, St. Lucia, Queensland, 4072, Australia
| | - Zhiguo Yuan
- Advanced Water Management Centre, The University of Queensland, St. Lucia, Queensland, 4072, Australia
| | - Jianhua Guo
- Advanced Water Management Centre, The University of Queensland, St. Lucia, Queensland, 4072, Australia.
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Zeng L, Chen H, Liu L, Zhou Q, Wang D. Reducing nitrous oxide emission in a sequencing batch reactor operated as static/aerobic/anoxic (SOA) process. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 693:133619. [PMID: 31376759 DOI: 10.1016/j.scitotenv.2019.133619] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 07/25/2019] [Accepted: 07/25/2019] [Indexed: 06/10/2023]
Abstract
The static/aerobic/anoxic (SOA) activated sludge process was implemented to investigate the nitrous oxide (N2O) emission characteristics with the conventional anaerobic/anoxic/oxic (A2/O) process as a control group. Although the SOA process can achieve substantial biological nutrient removal (BNR), its N2O emission was increased compared with the traditional A2/O process. The improvement of the SOA process was carried out by shortening the static time from 60 min to 15 min. SOA with 30-min static time had an advantage over that with 60-min static time in N2O mitigation with emission factors decreasing from 7.32% to 3.69% of total nitrogen removed and proved more effective in phosphorus removal than the 15-min static time process. 30-min static time induced more eternal carbon sources consumed in the inception of the aerobic phase, which induced less N2O generation in the SOA process. The results demonstrated that the modified SOA could be an alternative process for BNR and N2O mitigation.
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Affiliation(s)
- Long Zeng
- College of Environment and Resources, Xiangtan University, Xiangtan 411105, China
| | - Hongbo Chen
- College of Environment and Resources, Xiangtan University, Xiangtan 411105, China.
| | - Lin Liu
- College of Environment and Resources, Xiangtan University, Xiangtan 411105, China
| | - Qiongzhi Zhou
- College of Environment and Resources, Xiangtan University, Xiangtan 411105, China
| | - Dongbo Wang
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China
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Fenu A, Smolders S, De Gussem K, Weemaes M. Conflicting carbon footprint and energy saving in a side-stream Anammox Process. Biochem Eng J 2019. [DOI: 10.1016/j.bej.2019.107336] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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27
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Chen X, Sin G, Ni BJ. Impact of granule size distribution on nitrous oxide production in autotrophic nitrogen removal granular reactor. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 689:700-708. [PMID: 31280151 DOI: 10.1016/j.scitotenv.2019.06.490] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 06/23/2019] [Accepted: 06/28/2019] [Indexed: 06/09/2023]
Abstract
This work applied an approach with reactor compartmentation and artificial diffusion to study the impact of granule size distribution on the autotrophic granular reactor performing partial nitritation and anaerobic ammonium oxidation with focus on the nitrous oxide (N2O) production. The results show that the microbial community and the associated N2O production rates in the granular structure are significantly influenced by the granule size distribution. Heterotrophic bacteria growing on microbial decay products tend to be retained and contribute to N2O consumption in relatively small granules. Ammonium-oxidizing bacteria are mainly responsible for N2O production via two pathways in granules of different sizes. Under the conditions studied, such heterogeneity in the granular structure disappears when the number of granule size classes considered reaches >4, where heterotrophic bacteria are completely outcompeted in the granules. In general, larger granules account for a higher portion of the net N2O production, while the trend regarding the volumetric contribution of each granule size class changes with a varied number of granule size classes, due to the different contributions of relevant N2O production pathways (with the heterotrophic denitrification pathway being the most decisive). Overall, with the increasing extent of granule size distribution, the nitrogen removal efficiency decreases slightly but consistently, whereas the N2O production factor increases until the number of granule size classes reaches 4 or above. Practical implications of this work include: i) granules should be controlled as well-distributed as possible in order to obtain high nitrogen removal while minimizing N2O production; ii) granule size distribution should be considered carefully and specifically when modelling N2O production/emission from the autotrophic nitrogen removal granular reactor.
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Affiliation(s)
- Xueming Chen
- Process and Systems Engineering Center (PROSYS), Department of Chemical and Biochemical Engineering, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Gürkan Sin
- Process and Systems Engineering Center (PROSYS), Department of Chemical and Biochemical Engineering, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark.
| | - Bing-Jie Ni
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW 2007, Australia.
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28
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Suenaga T, Hori T, Riya S, Hosomi M, Smets BF, Terada A. Enrichment, Isolation, and Characterization of High-Affinity N 2O-Reducing Bacteria in a Gas-Permeable Membrane Reactor. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:12101-12112. [PMID: 31517481 DOI: 10.1021/acs.est.9b02237] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The recent discovery of nitrous oxide (N2O)-reducing bacteria suggests a potential biological sink for the potent greenhouse gas N2O. For an application toward N2O mitigation, characterization of more isolates will be required. Here, we describe the successful enrichment and isolation of high-affinity N2O-reducing bacteria using a N2O-fed reactor (N2OFR). Two N2OFRs, where N2O was continuously and directly supplied as the sole electron acceptor to a biofilm grown on a gas-permeable membrane, were operated with acetate or a mixture of peptone-based organic substrates as an electron donor. In parallel, a NO3- -fed reactor (NO3FR), filled with a nonwoven sheet substratum, was operated using the same inoculum. We hypothesized that supplying N2O vs NO3- would enhance the dominance of distinct N2O-reducing bacteria. Clade II type nosZ bacteria became rapidly enriched over clade I type nosZ bacteria in the N2OFRs, whereas the opposite held in the NO3FR. High-throughput sequencing of 16S rRNA gene amplicons revealed the dominance of Rhodocyclaceae in the N2OFRs. Strains of the Azospira and Dechloromonas genera, canonical denitrifiers harboring clade II type nosZ, were isolated with high frequency from the N2OFRs (132 out of 152 isolates). The isolates from the N2OFR demonstrated higher N2O uptake rates (Vmax: 4.23 × 10-3-1.80 × 10-2 pmol/h/cell) and lower N2O half-saturation coefficients (Km,N2O: 1.55-2.10 μM) than a clade I type nosZ isolate from the NO3FR. Furthermore, the clade II type nosZ isolates had higher specific growth rates on N2O than nitrite as an electron acceptor. Hence, continuously and exclusively supplying N2O in an N2OFR allows the enrichment and isolation of high-affinity N2O-reducing strains, which may be used as N2O sinks in bioaugmentation efforts.
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Affiliation(s)
- Toshikazu Suenaga
- Department of Chemical Engineering , Tokyo University of Agriculture and Technology , 2-24-16 Naka-cho , Koganei , Tokyo 184-8588 , Japan
- Institute of Global Innovation Research , Tokyo University of Agriculture and Technology , 3-8-1 Harumi-cho , Fuchu , Tokyo 185-8538 , Japan
| | - Tomoyuki Hori
- Environmental Management Research Institute , National Institute of Advanced Industrial Science and Technology (AIST) , Onogawa 16-1 , Tsukuba , Ibaraki 305-8569 , Japan
| | - Shohei Riya
- Department of Chemical Engineering , Tokyo University of Agriculture and Technology , 2-24-16 Naka-cho , Koganei , Tokyo 184-8588 , Japan
- Institute of Global Innovation Research , Tokyo University of Agriculture and Technology , 3-8-1 Harumi-cho , Fuchu , Tokyo 185-8538 , Japan
| | - Masaaki Hosomi
- Department of Chemical Engineering , Tokyo University of Agriculture and Technology , 2-24-16 Naka-cho , Koganei , Tokyo 184-8588 , Japan
| | - Barth F Smets
- Institute of Global Innovation Research , Tokyo University of Agriculture and Technology , 3-8-1 Harumi-cho , Fuchu , Tokyo 185-8538 , Japan
- Department of Environmental Engineering , Technical University of Denmark , Miljoevej, Lyngby 2800 , Denmark
| | - Akihiko Terada
- Department of Chemical Engineering , Tokyo University of Agriculture and Technology , 2-24-16 Naka-cho , Koganei , Tokyo 184-8588 , Japan
- Institute of Global Innovation Research , Tokyo University of Agriculture and Technology , 3-8-1 Harumi-cho , Fuchu , Tokyo 185-8538 , Japan
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29
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Domingo-Félez C, Smets BF. Regulation of key N2O production mechanisms during biological water treatment. Curr Opin Biotechnol 2019; 57:119-126. [DOI: 10.1016/j.copbio.2019.03.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 01/11/2019] [Accepted: 03/05/2019] [Indexed: 11/26/2022]
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30
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Su Q, Domingo-Félez C, Zhang Z, Blum JM, Jensen MM, Smets BF. The effect of pH on N 2O production in intermittently-fed nitritation reactors. WATER RESEARCH 2019; 156:223-231. [PMID: 30921538 DOI: 10.1016/j.watres.2019.03.015] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 02/28/2019] [Accepted: 03/12/2019] [Indexed: 06/09/2023]
Abstract
The effect of pH on nitrous oxide (N2O) production rates was quantified in an intermittently-fed lab-scale sequencing batch reactor performing high-rate nitritation. N2O and other nitrogen (N) species (e.g. ammonium (NH4+), nitrite, hydroxylamine and nitric oxide) were monitored to identify in-cycle dynamics and determine N conversion rates at controlled pH set-points (6.5, 7, 7.5, 8 and 8.5). Operational conditions and microbial compositions remained similar during long-term reactor-scale pH campaigns. The specific ammonium removal rates and nitrite accumulation rates varied little with varying pH levels (p > 0.05). The specific net N2O production rates and net N2O yield of NH4+ removed (ΔN2O/ΔNH4+) increased up to seven-fold from pH 6.5 to 8, and decreased slightly with further pH increase to 8.5 (p < 0.05). Best-fit model simulations predicted nitrifier denitrification as the dominant N2O production pathway (≥87% of total net N2O production) at all examined pH. Our study highlights the effect of pH on biologically mediated N2O emissions in nitrogen removal systems and its importance in the design of N2O mitigation strategies.
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Affiliation(s)
- Qingxian Su
- Department of Environmental Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Carlos Domingo-Félez
- Department of Environmental Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Zhen Zhang
- Department of Environmental Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Jan-Michael Blum
- Department of Environmental Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Marlene Mark Jensen
- Department of Environmental Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark.
| | - Barth F Smets
- Department of Environmental Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
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31
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Kanders L, Yang JJ, Baresel C, Zambrano J. Full-scale comparison of N 2O emissions from SBR N/DN operation versus one-stage deammonification MBBR treating reject water - and optimization with pH set-point. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2019; 79:1616-1625. [PMID: 31169520 DOI: 10.2166/wst.2019.163] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
To be able to fulfill the Paris agreement regarding anthropogenic greenhouse gases, all potential emissions must be mitigated. Wastewater treatment plants should aim to eliminate emissions of the most potent greenhouse gas, nitrous oxide (N2O). In this study, these emissions were measured at a full-scale reject water treatment tank during two different operation modes: nitrification/denitrification (N/DN) operating as a sequencing batch reactor (SBR), and deammonification (nitritation/anammox) as a moving bed biofilm reactor (MBBR). The treatment process emitted significantly less nitrous oxide in deammonification mode 0.14-0.7%, compared to 10% of total nitrogen in N/DN mode. The decrease can be linked to the changed feeding strategy, the lower concentrations of nitrite, a lower load of ammonia oxidized, a shorter aeration time, the absence of non-optimized ethanol dosage or periodic lack of oxygen as well as the introduction of biofilm. Further, evaluation was done how the operational pH set point influenced the emissions in deammonification mode. Lower concentrations of nitrous oxide were measured in water phase at higher pH (7.5-7.6) than at lower pH (6.6-7.1). This is believed to be mainly because of the lower aeration ratio and increased complete denitrification at the higher pH set point.
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Affiliation(s)
- L Kanders
- Purac AB, Box 1146, SE-221 05 Lund, Sweden E-mail: ; School of Business, Society and Engineering, Mälardalen University, Box 883, SE-721 23 Västerås, Sweden
| | - J-J Yang
- IVL Swedish Environmental Research Institute, Box 210 60, SE-100 31 Stockholm, Sweden
| | - C Baresel
- IVL Swedish Environmental Research Institute, Box 210 60, SE-100 31 Stockholm, Sweden
| | - J Zambrano
- School of Business, Society and Engineering, Mälardalen University, Box 883, SE-721 23 Västerås, Sweden
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32
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Wan X, Baeten JE, Volcke EI. Effect of operating conditions on N2O emissions from one-stage partial nitritation-anammox reactors. Biochem Eng J 2019. [DOI: 10.1016/j.bej.2018.12.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Vieira A, Galinha CF, Oehmen A, Carvalho G. The link between nitrous oxide emissions, microbial community profile and function from three full-scale WWTPs. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 651:2460-2472. [PMID: 30336436 DOI: 10.1016/j.scitotenv.2018.10.132] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2018] [Revised: 09/28/2018] [Accepted: 10/10/2018] [Indexed: 06/08/2023]
Abstract
Few attempts have been made in previous studies to link the microbial community structure and function with nitrous oxide (N2O) emissions at full-scale wastewater treatment plants (WWTPs). In this work, high-throughput sequencing and reverse transcriptase-qPCR (RT-qPCR) was applied to activated sludge samples from three WWTPs for two seasonal periods (winter and summer) and linked with the N2O emissions and wastewater characteristics. The total N2O emissions ranged from 7.2 to 937.0 g N-N2O/day, which corresponds to an emission factor of 0.001 to 0.280% of the influent NH4-N being emitted as N2O. Those emissions were related to the abundance of Nitrotoga, Candidatus Microthrix and Rhodobacter genera, which were favored by higher dissolved oxygen (DO) and nitrate (NO3-) concentrations in the activated sludge tanks. Furthermore, a relationship between the nirK gene expression and N2O emissions was verified. Detected N2O emission peaks were associated with different process events, related to aeration transition periods, that occurred during the regular operation of the plants, which could be potentially associated to increased emissions of the WWTP. The design of mitigation strategies, such as optimizing the aeration regime, is therefore important to avoid process events that lead to those N2O emissions peaks. Furthermore, this study also demonstrates the importance of assessing the gene expression of nosZ clade II, since its high abundance in WWTPs could be an important key to reduce the N2O emissions.
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Affiliation(s)
- A Vieira
- iBET - Instituto de Biologia Experimental e Tecnológica, Av. República, Qta. do Marquês, 2780-157 Oeiras, Portugal; ITQB - Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Quinta do Marquês, 2780-157 Oeiras, Portugal
| | - C F Galinha
- LAQV-REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Portugal
| | - A Oehmen
- UCIBIO-REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Portugal; School of Chemical Engineering, The University of Queensland, St Lucia, QLD 4072, Australia
| | - G Carvalho
- UCIBIO-REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Portugal; Advanced Water Management Centre (AWMC), The University of Queensland, St Lucia, QLD 4072, Australia.
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Chen X, Ni B, Sin G. Nitrous oxide production in autotrophic nitrogen removal granular sludge: A modeling study. Biotechnol Bioeng 2019; 116:1280-1291. [DOI: 10.1002/bit.26937] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Revised: 01/19/2019] [Accepted: 01/24/2019] [Indexed: 11/09/2022]
Affiliation(s)
- Xueming Chen
- Process and Systems Engineering Center (PROSYS), Department of Chemical and Biochemical Engineering Technical University of Denmark Lyngby Denmark
| | - Bing‐Jie Ni
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney Sydney New South Wales Australia
| | - Gürkan Sin
- Process and Systems Engineering Center (PROSYS), Department of Chemical and Biochemical Engineering Technical University of Denmark Lyngby Denmark
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35
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Schoepp T, Bousek J, Beqaj A, Fiedler C, Wett B, Fuchs W, Ertl T, Weissenbacher N. Nitrous oxide emissions of a mesh separated single stage deammonification reactor. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2018; 78:2239-2246. [PMID: 30699075 DOI: 10.2166/wst.2018.500] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
It is widely accepted that partial nitrification by ANAMMOX has the potential to become one of the key processes in wastewater treatment. However, large greenhouse gas emissions have been panobserved in many cases. A novel mesh separated reactor, developed to allow continuous operation of deammonification at smaller scale without external biomass selection, was compared to a conventional single-chamber deammonification sequencing batch reactor (SBR), where both were equally-sized pilot-scale reactors. The mesh reactor consisted of an aerated and an anoxic zone separated by a mesh. The resulting differences in the structure of the microbial community were detected by next-generation sequencing. When both systems were operated in a sequencing batch mode, both systems had comparable nitrous oxide emission factors in the range of 4% to 5% of the influent nitrogen load. A significant decrease was observed after switching from sequencing batch mode to continuous operation.
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Affiliation(s)
- T Schoepp
- Institute of Sanitary Engineering and Water Pollution Control, University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Wien, Vienna, Austria E-mail:
| | - J Bousek
- Institute for Environmental Biotechnology, IFA-Tulln, University of Natural Resources and Life Sciences, Konrad-Lorenz Straße 20, 3430 Tulln, Vienna, Austria
| | - A Beqaj
- Institute of Sanitary Engineering and Water Pollution Control, University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Wien, Vienna, Austria E-mail:
| | - C Fiedler
- Institute of Sanitary Engineering and Water Pollution Control, University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Wien, Vienna, Austria E-mail:
| | - B Wett
- ARAconsult, Unterbergerstr. 1, 6020 Innsbruck, Austria
| | - W Fuchs
- Institute for Environmental Biotechnology, IFA-Tulln, University of Natural Resources and Life Sciences, Konrad-Lorenz Straße 20, 3430 Tulln, Vienna, Austria
| | - T Ertl
- Institute of Sanitary Engineering and Water Pollution Control, University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Wien, Vienna, Austria E-mail:
| | - N Weissenbacher
- Institute of Sanitary Engineering and Water Pollution Control, University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Wien, Vienna, Austria E-mail:
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36
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Sabba F, Terada A, Wells G, Smets BF, Nerenberg R. Nitrous oxide emissions from biofilm processes for wastewater treatment. Appl Microbiol Biotechnol 2018; 102:9815-9829. [DOI: 10.1007/s00253-018-9332-7] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 08/13/2018] [Accepted: 08/15/2018] [Indexed: 01/21/2023]
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37
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Immobilization of Azospira sp. strain I13 by gel entrapment for mitigation of N2O from biological wastewater treatment plants: Biokinetic characterization and modeling. J Biosci Bioeng 2018; 126:213-219. [DOI: 10.1016/j.jbiosc.2018.02.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 02/13/2018] [Accepted: 02/18/2018] [Indexed: 11/23/2022]
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38
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Li X, Klaus S, Bott C, He Z. Status, Challenges, and Perspectives of Mainstream Nitritation-Anammox for Wastewater Treatment. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2018; 90:634-649. [PMID: 30188280 DOI: 10.2175/106143017x15131012153112] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
The nitritation-anammox process is an efficient and cost-effective approach for biological nitrogen removal, but its application in treating mainstream wastewater remains a great challenge. Mainstream nitritation-anammox processes could create opportunities for achieving energy self-sufficient, or energy-generating water resource recovery facilities. Significant advancements have been achieved via pilot- and full-scale trials to overcome the major obstacles under mainstream conditions, such as repression of nitrite-oxidizing bacteria, limiting the overgrowth of denitrifiers, and effective selection and retention of ammonia-oxidizing bacteria and anammox bacteria. This review paper intends to provide a detailed update of research progress on mainstream nitritation-anammox processes, discuss metabolic interactions, and examine major challenges and possible solutions towards the future development.
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Affiliation(s)
- Xiaojin Li
- Department of Civil and Environmental Engineering, Virginia Tech, Blacksburg, VA 24061, USA
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39
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Weißbach M, Thiel P, Drewes JE, Koch K. Nitrogen removal and intentional nitrous oxide production from reject water in a coupled nitritation/nitrous denitritation system under real feed-stream conditions. BIORESOURCE TECHNOLOGY 2018; 255:58-66. [PMID: 29414173 DOI: 10.1016/j.biortech.2018.01.080] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 01/14/2018] [Accepted: 01/16/2018] [Indexed: 06/08/2023]
Abstract
A Coupled Aerobic-anoxic Nitrous Decomposition Operation (CANDO) was performed over five months to investigate the performance and dynamics of nitrogen elimination and nitrous oxide production from digester reject water under real feed-stream conditions. A 93% conversion of ammonium to nitrite could be maintained for adapted seed sludge in the first stage (nitritation). The second stage (nitrous denitritation), inoculated with conventional activated sludge, achieved a conversion of 70% of nitrite to nitrous oxide after only 12 cycles of operation. The development of an alternative feeding strategy and the addition of a coagulant (FeCl3) facilitated stable operation and process intensification. Under steady-state conditions, nitrite was reliably eliminated and different nitrous oxide harvesting strategies were assessed. Applying continuous removal increased N2O yields by 16% compared to the application of a dedicated stripping phase. These results demonstrate the feasible application of the CANDO process for nitrogen removal and energy recovery from ammonia rich wastewater.
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Affiliation(s)
- Max Weißbach
- Chair of Urban Water Systems Engineering, Technical University of Munich, Am Coulombwall 3, 85748 Garching, Germany
| | - Paul Thiel
- Chair of Urban Water Systems Engineering, Technical University of Munich, Am Coulombwall 3, 85748 Garching, Germany
| | - Jörg E Drewes
- Chair of Urban Water Systems Engineering, Technical University of Munich, Am Coulombwall 3, 85748 Garching, Germany
| | - Konrad Koch
- Chair of Urban Water Systems Engineering, Technical University of Munich, Am Coulombwall 3, 85748 Garching, Germany.
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40
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Kinh CT, Suenaga T, Hori T, Riya S, Hosomi M, Smets BF, Terada A. Counter-diffusion biofilms have lower N 2O emissions than co-diffusion biofilms during simultaneous nitrification and denitrification: Insights from depth-profile analysis. WATER RESEARCH 2017; 124:363-371. [PMID: 28780360 DOI: 10.1016/j.watres.2017.07.058] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Revised: 07/18/2017] [Accepted: 07/23/2017] [Indexed: 06/07/2023]
Abstract
The goal of this study was to investigate the effectiveness of a membrane-aerated biofilm reactor (MABR), a representative of counter-current substrate diffusion geometry, in mitigating nitrous oxide (N2O) emission. Two laboratory-scale reactors with the same dimensions but distinct biofilm geometries, i.e., a MABR and a conventional biofilm reactor (CBR) employing co-current substrate diffusion geometry, were operated to determine depth profiles of dissolved oxygen (DO), nitrous oxide (N2O), functional gene abundance and microbial community structure. Surficial nitrogen removal rate was slightly higher in the MABR (11.0 ± 0.80 g-N/(m2 day) than in the CBR (9.71 ± 0.94 g-N/(m2 day), while total organic carbon removal efficiencies were comparable (96.9 ± 1.0% for MABR and 98.0 ± 0.8% for CBR). In stark contrast, the dissolved N2O concentration in the MABR was two orders of magnitude lower (0.011 ± 0.001 mg N2O-N/L) than that in the CBR (1.38 ± 0.25 mg N2O-N/L), resulting in distinct N2O emission factors (0.0058 ± 0.0005% in the MABR vs. 0.72 ± 0.13% in the CBR). Analysis on local net N2O production and consumption rates unveiled that zones for N2O production and consumption were adjacent in the MABR biofilm. Real-time quantitative PCR indicated higher abundance of denitrifying genes, especially nitrous oxide reductase (nosZ) genes, in the MABR versus the CBR. Analyses of the microbial community composition via 16S rRNA gene amplicon sequencing revealed the abundant presence of the genera Thauera (31.2 ± 11%), Rhizobium (10.9 ± 6.6%), Stenotrophomonas (6.8 ± 2.7%), Sphingobacteria (3.2 ± 1.1%) and Brevundimonas (2.5 ± 1.0%) as potential N2O-reducing bacteria in the MABR.
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Affiliation(s)
- Co Thi Kinh
- Department of Chemical Engineering, Tokyo University of Agriculture and Technology, Naka 2-24-16, Koganei, Tokyo, 184-8588, Japan
| | - Toshikazu Suenaga
- Department of Chemical Engineering, Tokyo University of Agriculture and Technology, Naka 2-24-16, Koganei, Tokyo, 184-8588, Japan
| | - Tomoyuki Hori
- Institute for Environmental Management Technology, National Institute of Advanced Industrial Science and Technology (AIST), Onogawa 16-1, Tsukuba, Ibaraki, 305-8569, Japan
| | - Shohei Riya
- Department of Chemical Engineering, Tokyo University of Agriculture and Technology, Naka 2-24-16, Koganei, Tokyo, 184-8588, Japan
| | - Masaaki Hosomi
- Department of Chemical Engineering, Tokyo University of Agriculture and Technology, Naka 2-24-16, Koganei, Tokyo, 184-8588, Japan
| | - Barth F Smets
- Department of Environmental Engineering, Technical University of Denmark, Miljoevej, 2800, Lyngby, Denmark
| | - Akihiko Terada
- Department of Chemical Engineering, Tokyo University of Agriculture and Technology, Naka 2-24-16, Koganei, Tokyo, 184-8588, Japan.
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41
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Su Q, Ma C, Domingo-Félez C, Kiil AS, Thamdrup B, Jensen MM, Smets BF. Low nitrous oxide production through nitrifier-denitrification in intermittent-feed high-rate nitritation reactors. WATER RESEARCH 2017; 123:429-438. [PMID: 28689127 DOI: 10.1016/j.watres.2017.06.067] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 05/24/2017] [Accepted: 06/19/2017] [Indexed: 06/07/2023]
Abstract
Nitrous oxide (N2O) production from autotrophic nitrogen conversion processes, especially nitritation systems, can be significant, requires understanding and calls for mitigation. In this study, the rates and pathways of N2O production were quantified in two lab-scale sequencing batch reactors operated with intermittent feeding and demonstrating long-term and high-rate nitritation. The resulting reactor biomass was highly enriched in ammonia-oxidizing bacteria, and converted ∼93 ± 14% of the oxidized ammonium to nitrite. The low DO set-point combined with intermittent feeding was sufficient to maintain high nitritation efficiency and high nitritation rates at 20-26 °C over a period of ∼300 days. Even at the high nitritation efficiencies, net N2O production was low (∼2% of the oxidized ammonium). Net N2O production rates transiently increased with a rise in pH after each feeding, suggesting a potential effect of pH on N2O production. In situ application of 15N labeled substrates revealed nitrifier denitrification as the dominant pathway of N2O production. Our study highlights operational conditions that minimize N2O emission from two-stage autotrophic nitrogen removal systems.
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Affiliation(s)
- Qingxian Su
- Department of Environmental Engineering, Technical University of Denmark, 2800 Lyngby, Denmark
| | - Chun Ma
- Nordic Center for Earth Evolution and Institute of Biology, University of Southern Denmark, 5230 Odense M, Denmark
| | - Carlos Domingo-Félez
- Department of Environmental Engineering, Technical University of Denmark, 2800 Lyngby, Denmark
| | - Anne Sofie Kiil
- Department of Environmental Engineering, Technical University of Denmark, 2800 Lyngby, Denmark
| | - Bo Thamdrup
- Nordic Center for Earth Evolution and Institute of Biology, University of Southern Denmark, 5230 Odense M, Denmark
| | - Marlene Mark Jensen
- Department of Environmental Engineering, Technical University of Denmark, 2800 Lyngby, Denmark.
| | - Barth F Smets
- Department of Environmental Engineering, Technical University of Denmark, 2800 Lyngby, Denmark
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42
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Yoon H, Song MJ, Yoon S. Design and Feasibility Analysis of a Self-Sustaining Biofiltration System for Removal of Low Concentration N 2O Emitted from Wastewater Treatment Plants. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:10736-10745. [PMID: 28849922 DOI: 10.1021/acs.est.7b02750] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
N2O is a potent greenhouse gas and ozone-depletion agent. In this study, a biofiltration system was designed for removal of N2O emitted at low concentrations (<200 ppmv) from wastewater treatment plants. The proposed biofiltration system utilizes untreated wastewater from the primary sedimentation basin as the source of electron donor and nutrients and energy requirement is minimized by utilizing gravitational force and pressure differential to direct liquid medium and gas through the biofilter. The experiments performed with laboratory-scale biofilter in two different configurations confirmed the feasibility of the biofiltration system. The biofilter operated with cycling of raw wastewater exhibited up to 94% and 53% removal efficiency with 100 ppmv N2O in N2 and air, respectively, as the feed gas, corroborating that untreated wastewater can serve as a robust source of electron donor and nutrients. The laboratory-scale biofilter operated with a continuous flow-through of synthetic wastewater attained >99.9% removal of N2O from N2 background at the gas flow rate up to 2,000 mL·min-1 and >50% N2O removal from air background at the gas flow rate of 200 mL·min-1. nosZ-containing bacterial genera including Flavobacterium (5.92%), Pseudomonas (4.26%) and Bosea (2.39%) were identified in the biofilm samples collected from the oxic biofilter, indicating these organisms were responsible for N2O removal.
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Affiliation(s)
- Hyun Yoon
- Department of Civil and Environmental Engineering, KAIST , Daejeon, 34141, Korea
| | - Min Joon Song
- Department of Civil and Environmental Engineering, KAIST , Daejeon, 34141, Korea
| | - Sukhwan Yoon
- Department of Civil and Environmental Engineering, KAIST , Daejeon, 34141, Korea
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43
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Ma C, Jensen MM, Smets BF, Thamdrup B. Pathways and Controls of N 2O Production in Nitritation-Anammox Biomass. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:8981-8991. [PMID: 28669192 DOI: 10.1021/acs.est.7b01225] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Nitrous oxide (N2O) is an unwanted byproduct during biological nitrogen removal processes in wastewater. To establish strategies for N2O mitigation, a better understanding of production mechanisms and their controls is required. A novel stable isotope labeling approach using 15N and 18O was applied to investigate pathways and controls of N2O production by biomass taken from a full-scale nitritation-anammox reactor. The experiments showed that heterotrophic denitrification was a negligible source of N2O under oxic conditions (≥0.2 mg O2 L-1). Both hydroxylamine oxidation and nitrifier denitrification contributed substantially to N2O accumulation across a wide range of conditions with varying concentrations of O2, NH4+, and NO2-. The O2 concentration exerted the strongest control on net N2O production with both production pathways stimulated by low O2, independent of NO2- concentrations. The stimulation of N2O production from hydroxylamine oxidation at low O2 was unexpected and suggests that more than one enzymatic pathway may be involved in this process. N2O production by hydroxylamine oxidation was further stimulated by NH4+, whereas nitrifier denitrification at low O2 levels was stimulated by NO2- at levels as low as 0.2 mM. Our study shows that 15N and 18O isotope labeling is a useful approach for direct quantification of N2O production pathways applicable to diverse environments.
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Affiliation(s)
- Chun Ma
- Department of Biology, University of Southern Denmark , 5230 Odense M, Denmark
| | - Marlene Mark Jensen
- Department of Environmental Engineering, Technical University of Denmark , 2800 Kongens Lyngby, Denmark
| | - Barth F Smets
- Department of Environmental Engineering, Technical University of Denmark , 2800 Kongens Lyngby, Denmark
| | - Bo Thamdrup
- Department of Biology, University of Southern Denmark , 5230 Odense M, Denmark
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44
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Leix C, Drewes JE, Ye L, Koch K. Strategies for enhanced deammonification performance and reduced nitrous oxide emissions. BIORESOURCE TECHNOLOGY 2017; 236:174-185. [PMID: 28402907 DOI: 10.1016/j.biortech.2017.03.182] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Revised: 03/27/2017] [Accepted: 03/30/2017] [Indexed: 06/07/2023]
Abstract
Deammonification's performance and associated nitrous oxide emissions (N2O) depend on operational conditions. While studies have investigated factors for high performances and low emissions separately, this study investigated optimizing deammonification performance while simultaneously reducing N2O emissions. Using a design of experiment (DoE) method, two models were developed for the prediction of the nitrogen removal rate and N2O emissions during single-stage deammonification considering three operational factors (i.e., pH value, feeding and aeration strategy). The emission factor varied between 0.7±0.5% and 4.1±1.2% at different DoE-conditions. The nitrogen removal rate was predicted to be maximized at settings of pH 7.46, intermittent feeding and aeration. Conversely, emissions were predicted to be minimized at the design edges at pH 7.80, single feeding, and continuous aeration. Results suggested a weak positive correlation between the nitrogen removal rate and N2O emissions, thus, a single optimizing operational set-point for maximized performance and minimized emissions did not exist.
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Affiliation(s)
- Carmen Leix
- Technical University of Munich, Am Coulombwall 3, 85748 Garching, Germany.
| | - Jörg E Drewes
- Technical University of Munich, Am Coulombwall 3, 85748 Garching, Germany.
| | - Liu Ye
- School of Chemical Engineering, The University of Queensland, St. Lucia, Queensland 4072, Australia.
| | - Konrad Koch
- Technical University of Munich, Am Coulombwall 3, 85748 Garching, Germany.
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45
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Performance and N2O Formation of the Deammonification Process by Suspended Sludge and Biofilm Systems—A Pilot-Scale Study. WATER 2016. [DOI: 10.3390/w8120578] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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46
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Ali M, Rathnayake RMLD, Zhang L, Ishii S, Kindaichi T, Satoh H, Toyoda S, Yoshida N, Okabe S. Source identification of nitrous oxide emission pathways from a single-stage nitritation-anammox granular reactor. WATER RESEARCH 2016; 102:147-157. [PMID: 27340816 DOI: 10.1016/j.watres.2016.06.034] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 06/13/2016] [Accepted: 06/13/2016] [Indexed: 06/06/2023]
Abstract
Nitrous oxide (N2O) production pathway in a signal-stage nitritation-anammox sequencing batch reactor (SBR) was investigated based on a multilateral approach including real-time N2O monitoring, N2O isotopic composition analysis, and in-situ analyses of spatial distribution of N2O production rate and microbial populations in granular biomass. N2O emission rate was high in the initial phase of the operation cycle and gradually decreased with decreasing NH4(+) concentration. The average emission of N2O was 0.98 ± 0.42% and 1.35 ± 0.72% of the incoming nitrogen load and removed nitrogen, respectively. The N2O isotopic composition analysis revealed that N2O was produced via NH2OH oxidation and NO2(-) reduction pathways equally, although there is an unknown influence from N2O reduction and/or anammox N2O production. However, the N2O isotopomer analysis could not discriminate the relative contribution of nitrifier denitrification and heterotrophic denitrification in the NO2(-) reduction pathway. Various in-situ techniques (e.g. microsensor measurements and FISH (fluorescent in-situ hybridization) analysis) were therefore applied to further identify N2O producers. Microsensor measurements revealed that approximately 70% of N2O was produced in the oxic surface zone, where nitrifiers were predominantly localized. Thus, NH2OH oxidation and NO2 reduction by nitrifiers (nitrifier-denitrification) could be responsible for the N2O production in the oxic zone. The rest of N2O (ca. 30%) was produced in the anammox bacteria-dominated anoxic zone, probably suggesting that NO2(-) reduction by coexisting putative heterotrophic denitrifiers and some other unknown pathway(s) including the possibility of anammox process account for the anaerobic N2O production. Further study is required to identify the anaerobic N2O production pathways. Our multilateral approach can be useful to quantitatively examine the relative contributions of N2O production pathways. Good understanding of the key N2O production pathways is essential to establish a strategy to mitigate N2O emission from biological nitrogen removal processes.
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Affiliation(s)
- Muhammad Ali
- Division of Environmental Engineering, Faculty of Engineering, Hokkaido University, North-13, West-8, Sapporo, Hokkaido 060-8628, Japan; Water Desalination and Reuse Center (WDRC), Biological and Environmental Science and Engineering (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Rathnayake M L D Rathnayake
- Division of Environmental Engineering, Faculty of Engineering, Hokkaido University, North-13, West-8, Sapporo, Hokkaido 060-8628, Japan; Department of Civil Engineering, Faculty of Engineering, University of Peradeniya, Peradeniya 20400, Sri Lanka
| | - Lei Zhang
- Division of Environmental Engineering, Faculty of Engineering, Hokkaido University, North-13, West-8, Sapporo, Hokkaido 060-8628, Japan
| | - Satoshi Ishii
- Division of Environmental Engineering, Faculty of Engineering, Hokkaido University, North-13, West-8, Sapporo, Hokkaido 060-8628, Japan; Department of Soil, Water and Climate, University of Minnesota, 258 Borlaug Hall, 1991 Upper Buford Circle, St. Paul, MN 55108, USA
| | - Tomonori Kindaichi
- Department of Civil and Environmental Engineering, Graduate School of Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashihiroshima, Hiroshima 739-8527, Japan
| | - Hisashi Satoh
- Division of Environmental Engineering, Faculty of Engineering, Hokkaido University, North-13, West-8, Sapporo, Hokkaido 060-8628, Japan
| | - Sakae Toyoda
- Department of Environmental Science and Technology, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8502, Japan
| | - Naohiro Yoshida
- Department of Environmental Science and Technology, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8502, Japan
| | - Satoshi Okabe
- Division of Environmental Engineering, Faculty of Engineering, Hokkaido University, North-13, West-8, Sapporo, Hokkaido 060-8628, Japan.
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47
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Domingo-Félez C, Pellicer-Nàcher C, Petersen MS, Jensen MM, Plósz BG, Smets BF. Heterotrophs are key contributors to nitrous oxide production in activated sludge under low C-to-N ratios during nitrification-Batch experiments and modeling. Biotechnol Bioeng 2016; 114:132-140. [DOI: 10.1002/bit.26062] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Revised: 07/06/2016] [Accepted: 07/28/2016] [Indexed: 11/07/2022]
Affiliation(s)
- Carlos Domingo-Félez
- Department of Environmental Engineering; Technical University of Denmark; Miljøvej 113 Kongens Lyngby 2800 Denmark
| | - Carles Pellicer-Nàcher
- Department of Environmental Engineering; Technical University of Denmark; Miljøvej 113 Kongens Lyngby 2800 Denmark
| | - Morten S. Petersen
- Department of Environmental Engineering; Technical University of Denmark; Miljøvej 113 Kongens Lyngby 2800 Denmark
| | - Marlene M. Jensen
- Department of Environmental Engineering; Technical University of Denmark; Miljøvej 113 Kongens Lyngby 2800 Denmark
| | - Benedek G. Plósz
- Department of Environmental Engineering; Technical University of Denmark; Miljøvej 113 Kongens Lyngby 2800 Denmark
| | - Barth F. Smets
- Department of Environmental Engineering; Technical University of Denmark; Miljøvej 113 Kongens Lyngby 2800 Denmark
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48
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Liu RT, Wang XH, Zhang Y, Wang MY, Gao MM, Wang SG. Optimization of operation conditions for the mitigation of nitrous oxide (N2O) emissions from aerobic nitrifying granular sludge system. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2016; 23:9518-9528. [PMID: 26841778 DOI: 10.1007/s11356-016-6178-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Accepted: 01/25/2016] [Indexed: 06/05/2023]
Abstract
The optimization of operation parameters is a key consideration to minimize nitrous oxide (N2O) emissions in biological nitrogen removal processes. So far, different parameters have only been investigated individually, making it difficult to compare their specific effects and combined influences. In this study, we applied the Plackett-Burman (PB) multifactorial experimental design and response surface methodology (RSM) analysis to find the optimized condition for the mitigation of N2O release in a nitrifying granular sludge system. Seven parameters (temperature, pH, feeding strategy, C/N ratio, aeration rate, Cu(2+) concentration, and aeration mode) were tested in parallel. Five of them (other than chemical oxygen demand/nitrogen (C/N) ratio and Cu(2+) concentration) were selected as influential factors. Since the type of feeding strategies and aeration modes cannot be quantified, continuous feed strategy and anoxic/oxic aeration mode were applied for the following study. Influences of temperature, pH, and aeration rate on N2O emissions were tested with RSM analysis to further investigate the mutual interactions among the parameters and to identify the optimal values that would minimize N2O release. Results showed the minimum emission value could be obtained under the temperature of 22.3 °C, pH of 7.1 and aeration rate of 0.20 m(3)/h. Predicted results were then verified by subsequent validation experiments. The estimated N2O emission value of each design by RSM was also observed in good relationships with experimental result.
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Affiliation(s)
- Rui-Ting Liu
- Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan, 250100, China
| | - Xin-Hua Wang
- Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan, 250100, China.
| | - Yan Zhang
- Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan, 250100, China
| | - Ming-Yu Wang
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, 250100, China
| | - Ming-Ming Gao
- Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan, 250100, China
| | - Shu-Guang Wang
- Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan, 250100, China
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49
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Yan Y, Wang Y, Chen Y, Lin X, Wu M, Chen J. Single-stage PN/A technology treating saline ammonia-rich wastewater: finding the balance between efficient performance and less N2O and NO emissions. RSC Adv 2016. [DOI: 10.1039/c6ra24109c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
N2O emission from a one-stage PN/A process was studied for the first time with elevated salinity.
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Affiliation(s)
- Yuan Yan
- State Key Laboratory of Pollution Control and Resources Reuse
- College of Environmental Science and Engineering
- Tongji University
- Shanghai 200092
- P. R. China
| | - Yayi Wang
- State Key Laboratory of Pollution Control and Resources Reuse
- College of Environmental Science and Engineering
- Tongji University
- Shanghai 200092
- P. R. China
| | - Yu Chen
- State Key Laboratory of Pollution Control and Resources Reuse
- College of Environmental Science and Engineering
- Tongji University
- Shanghai 200092
- P. R. China
| | - Ximao Lin
- State Key Laboratory of Pollution Control and Resources Reuse
- College of Environmental Science and Engineering
- Tongji University
- Shanghai 200092
- P. R. China
| | - Min Wu
- State Key Laboratory of Pollution Control and Resources Reuse
- College of Environmental Science and Engineering
- Tongji University
- Shanghai 200092
- P. R. China
| | - Jie Chen
- State Key Laboratory of Pollution Control and Resources Reuse
- College of Environmental Science and Engineering
- Tongji University
- Shanghai 200092
- P. R. China
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50
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Ni BJ, Pan Y, van den Akker B, Ye L, Yuan Z. Full-Scale Modeling Explaining Large Spatial Variations of Nitrous Oxide Fluxes in a Step-Feed Plug-Flow Wastewater Treatment Reactor. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:9176-84. [PMID: 26153721 DOI: 10.1021/acs.est.5b02038] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Nitrous oxide (N2O) emission data collected from wastewater treatment plants (WWTPs) show huge variations between plants and within one plant (both spatially and temporarily). Such variations and the relative contributions of various N2O production pathways are not fully understood. This study applied a previously established N2O model incorporating two currently known N2O production pathways by ammonia-oxidizing bacteria (AOB) (namely the AOB denitrification and the hydroxylamine pathways) and the N2O production pathway by heterotrophic denitrifiers to describe and provide insights into the large spatial variations of N2O fluxes in a step-feed full-scale activated sludge plant. The model was calibrated and validated by comparing simulation results with 40 days of N2O emission monitoring data as well as other water quality parameters from the plant. The model demonstrated that the relatively high biomass specific nitrogen loading rate in the Second Step of the reactor was responsible for the much higher N2O fluxes from this section. The results further revealed the AOB denitrification pathway decreased and the NH2OH oxidation pathway increased along the path of both Steps due to the increasing dissolved oxygen concentration. The overall N2O emission from this step-feed WWTP would be largely mitigated if 30% of the returned sludge were returned to the Second Step to reduce its biomass nitrogen loading rate.
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Affiliation(s)
- Bing-Jie Ni
- †Advanced Wastewater Management Centre, The University of Queensland, St. Lucia, Brisbane, Queensland 4072, Australia
| | - Yuting Pan
- †Advanced Wastewater Management Centre, The University of Queensland, St. Lucia, Brisbane, Queensland 4072, Australia
| | - Ben van den Akker
- ‡Australian Water Quality Centre, Adelaide, South Australia 5000, Australia
| | - Liu Ye
- †Advanced Wastewater Management Centre, The University of Queensland, St. Lucia, Brisbane, Queensland 4072, Australia
- §School of Chemical Engineering, The University of Queensland, St. Lucia, Brisbane, Queensland 4072, Australia
| | - Zhiguo Yuan
- †Advanced Wastewater Management Centre, The University of Queensland, St. Lucia, Brisbane, Queensland 4072, Australia
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