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Carvalho VCF, Gan AZM, Shon A, Kolakovic S, Freitas EB, Reis MAM, Fradinho JC, Oehmen A. The phototrophic metabolic behaviour of Candidatus accumulibacter. WATER RESEARCH 2024; 259:121865. [PMID: 38851111 DOI: 10.1016/j.watres.2024.121865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 05/30/2024] [Accepted: 05/31/2024] [Indexed: 06/10/2024]
Abstract
The phototrophic capability of Candidatus Accumulibacter (Accumulibacter), a common polyphosphate accumulating organism (PAO) in enhanced biological phosphorus removal (EBPR) systems, was investigated in this study. Accumulibacter is phylogenetically related to the purple bacteria Rhodocyclus from the family Rhodocyclaceae, which belongs to the class Betaproteobacteria. Rhodocyclus typically exhibits both chemoheterotrophic and phototrophic growth, however, limited studies have evaluated the phototrophic potential of Accumulibacter. To address this gap, short and extended light cycle tests were conducted using a highly enriched Accumulibacter culture (95%) to evaluate its responses to illumination. Results showed that, after an initial period of adaptation to light conditions (approximately 4-5 h), Accumulibacter exhibited complete phosphorus (P) uptake by utilising polyhydroxyalkanoates (PHA), and additionally by consuming glycogen, which contrasted with its typical aerobic metabolism. Mass, energy, and redox balance analyses demonstrated that Accumulibacter needed to employ phototrophic metabolism to meet its energy requirements. Calculations revealed that the light reactions contributed to the generation of, at least more than 67% of the ATP necessary for P uptake and growth. Extended light tests, spanning 21 days with dark/light cycles, suggested that Accumulibacter generated ATP through light during initial operation, however, it likely reverted to conventional anaerobic/aerobic metabolism under dark/light conditions due to microalgal growth in the mixed culture, contributing to oxygen production. In contrast, extended light tests with an enriched Tetrasphaera culture, lacking phototrophic genes in its genome, clearly demonstrated that phototrophic P uptake did not occur. These findings highlight the adaptive metabolic capabilities of Accumulibacter, enabling it to utilise phototrophic pathways for energy generation during oxygen deprivation, which holds the potential to advance phototrophic-EBPR technology development.
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Affiliation(s)
- V C F Carvalho
- Associate Laboratory i4HB - Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, 2829-516 Caparica, Portugal; UCIBIO - Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2829-516 Caparica, Portugal
| | - A Z M Gan
- School of Chemical Engineering, University of Queensland, Brisbane, QLD, 4072, Australia
| | - A Shon
- School of Chemical Engineering, University of Queensland, Brisbane, QLD, 4072, Australia
| | - S Kolakovic
- Associate Laboratory i4HB - Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, 2829-516 Caparica, Portugal; UCIBIO - Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2829-516 Caparica, Portugal
| | - E B Freitas
- Associate Laboratory i4HB - Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, 2829-516 Caparica, Portugal; UCIBIO - Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2829-516 Caparica, Portugal
| | - M A M Reis
- Associate Laboratory i4HB - Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, 2829-516 Caparica, Portugal; UCIBIO - Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2829-516 Caparica, Portugal
| | - J C Fradinho
- Associate Laboratory i4HB - Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, 2829-516 Caparica, Portugal; UCIBIO - Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2829-516 Caparica, Portugal
| | - A Oehmen
- Associate Laboratory i4HB - Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, 2829-516 Caparica, Portugal; UCIBIO - Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2829-516 Caparica, Portugal; School of Chemical Engineering, University of Queensland, Brisbane, QLD, 4072, Australia.
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2
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Zhang R, He J, Wang M, Duan S, Zhang J. Nitrate and nitrite utilization during denitrifying phosphorus removal: Electron acceptor preference and feasible process combinations. BIORESOURCE TECHNOLOGY 2024; 406:131081. [PMID: 38977037 DOI: 10.1016/j.biortech.2024.131081] [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: 05/15/2024] [Revised: 06/30/2024] [Accepted: 07/04/2024] [Indexed: 07/10/2024]
Abstract
Denitrifying phosphorus removal (DPR), which is dominated by denitrifying polyphosphate-accumulating organisms (DPAOs), is a promising process for nitrogen and phosphorus removal. Denitrifying glycogen-accumulating organisms (DGAOs) and DPAOs typically coexist in the DPR sludge, complicating the study of DPAOs' denitrification capacity. In this study, two reactors were fed with nitrate and nitrite during the anoxic phase to cultivate nitrate-DPR and nitrite-DPR sludge. Both reactors yielded high and low DGAO abundance sludges, enabling the evaluation of the denitrification capacity of DPAOs. For the nitrate-DPR sludge, the nitrite reduction rate was 1.63 times higher than the nitrate reduction rate when DPAOs were the primary denitrifiers. For the nitrite-DPR sludge, the reduction rate of nitrite was more than three times that of nitrate, irrespective of DGAO abundance. These findings indicated that DPAOs preferred nitrite to nitrate and were well suited to reduce nitrite rather than reduce nitrate to supply nitrite.
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Affiliation(s)
- Ruimiao Zhang
- School of Environment, Harbin Institute of Technology, Harbin 150090, Heilongjiang, PR China; State Key Laboratory of Urban Water Resources and Environment, Harbin Institute of Technology, Harbin 150090, Heilongjiang, PR China.
| | - Junguo He
- School of Civil Engineering, Guangzhou University, Guangzhou 510006, PR China
| | - Mengfei Wang
- School of Environment, Harbin Institute of Technology, Harbin 150090, Heilongjiang, PR China; State Key Laboratory of Urban Water Resources and Environment, Harbin Institute of Technology, Harbin 150090, Heilongjiang, PR China
| | - Shengye Duan
- School of Environment, Harbin Institute of Technology, Harbin 150090, Heilongjiang, PR China; State Key Laboratory of Urban Water Resources and Environment, Harbin Institute of Technology, Harbin 150090, Heilongjiang, PR China
| | - Jie Zhang
- School of Environment, Harbin Institute of Technology, Harbin 150090, Heilongjiang, PR China; State Key Laboratory of Urban Water Resources and Environment, Harbin Institute of Technology, Harbin 150090, Heilongjiang, PR China
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3
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Zhao Y, Zhu Z, Chen X, Li Y. Discovery of a novel potential polyphosphate accumulating organism without denitrifying phosphorus uptake function in an enhanced biological phosphorus removal process. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:168952. [PMID: 38043807 DOI: 10.1016/j.scitotenv.2023.168952] [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: 09/17/2023] [Revised: 11/14/2023] [Accepted: 11/25/2023] [Indexed: 12/05/2023]
Abstract
Enhanced biological phosphorus removal (EBPR) is an effective process for phosphorus removal from wastewater. In this study, two lab-scale sequencing batch reactors (SBR) were used to perform EBPR process, in which genus Propioniciclava was unexpectedly accumulated and its relative abundance was over 70 %. A series of tests were conducted to explore the role of Propioniciclava in the two EBPR systems. The two systems performed steadily throughout the study, and the phosphorus removal efficiencies were 96.6 % and 93.5 % for SBR1 and SBR2, respectively. The stoichiometric analysis related to polyphosphate accumulating organisms (PAOs) indicated that polyphosphate accumulating metabolism (PAM) was achieved in the anaerobic phase. It appeared that the Propioniciclava-dominated systems could not perform denitrifying phosphorus removal. Instead, phosphorus was released under anoxic conditions without carbon sources. According to the genomic information from Integrated Microbial Genomes (IMG) database, Propioniciclava owns ppk1, ppk2 and ppx genes that are associated with phosphorus release and uptake functions. By phylogenetic investigation of communities by reconstruction of unobserved states 2 (PICRUSt2) analysis, the abundance of genes related to phosphorus metabolism was much higher than that of genes related to denitrification. Therefore, Propioniciclava was presumed to be a potential PAO without denitrifying phosphorus uptake function. In addition to Propioniciclava, Tessaracoccus and Thiothrix were also enriched in both systems. Overall, this study proposes a novel potential PAO and broadens the understanding of EBPR microbial communities.
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Affiliation(s)
- Yiming Zhao
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Zhengyu Zhu
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Xuyang Chen
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Yongmei Li
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
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4
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Ma Y, Jiang W, Nie Z, Qi P, Jiao Y, Peng J, Bian D. Study on the mechanisms of enhanced biological nitrogen and phosphorus removal by denitrifying phosphorus removal in a Micro-pressure swirl reactor. BIORESOURCE TECHNOLOGY 2022; 364:128093. [PMID: 36229011 DOI: 10.1016/j.biortech.2022.128093] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 10/02/2022] [Accepted: 10/04/2022] [Indexed: 06/16/2023]
Abstract
To reveal the mechanisms of enhanced biological nitrogen and phosphorus removal by denitrifying phosphorus removal in a Micro-pressure swirl reactor (MPSR), this study used a MPSR to treat municipal wastewater and enriched denitrifying phosphate accumulating organisms (DPAOs) by using its alternating anaerobic-anoxic-aerobic environment. The coupling of denitrification phosphorus removal (DPR) and simultaneous nitrification endogenous denitrification phosphorus removal (SNEDPR) was achieved in MPSR, and the average removal rates of COD, NH4+-N, TN and TP were 91.57%, 98.51%, 85.88%, 96.08% respectively. The results of the batch experiments showed that DPAOs activity in the low dissolved oxygen (DO) and high DO zones were 70.5% and 74.3%. The results of intracellular carbon source conversion patterns, microbial assays and functional gene prediction indicated that Flavobacterium and Dechloromonas dominated the DPR process in the low DO zone. Based on these findings, nutrient removal pathways within the MPSR were integrated.
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Affiliation(s)
- Yunguang Ma
- Changchun Institute of Technology, Changchun 130012, China; Key Laboratory of Urban Sewage Treatment of Jilin Province , Changchun 130012, China
| | - Weiqing Jiang
- Changchun Institute of Technology, Changchun 130012, China; Key Laboratory of Urban Sewage Treatment of Jilin Province , Changchun 130012, China
| | - Zebing Nie
- Key Laboratory of Urban Sewage Treatment of Jilin Province , Changchun 130012, China; Science and Technology Innovation Center for Municipal Wastewater Treatment and Water Quality Protection, Northeast Normal University, Changchun 130117, China
| | - Peng Qi
- Changchun Institute of Technology, Changchun 130012, China; Key Laboratory of Urban Sewage Treatment of Jilin Province , Changchun 130012, China
| | - Yang Jiao
- Changchun Institute of Technology, Changchun 130012, China; Key Laboratory of Urban Sewage Treatment of Jilin Province , Changchun 130012, China
| | - Jiaxi Peng
- Changchun Institute of Technology, Changchun 130012, China; Key Laboratory of Urban Sewage Treatment of Jilin Province , Changchun 130012, China
| | - Dejun Bian
- Changchun Institute of Technology, Changchun 130012, China; Key Laboratory of Urban Sewage Treatment of Jilin Province , Changchun 130012, China.
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Wu T, Ding J, Yang SS, Zhong L, Liu BF, Xie GJ, Yang F, Pang JW, Ren NQ. A novel cross-flow honeycomb bionic carrier promotes simultaneous nitrification, denitrification and phosphorus removal in IFAS system: Performance, mechanism and keystone species. WATER RESEARCH 2022; 225:119132. [PMID: 36155005 DOI: 10.1016/j.watres.2022.119132] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 09/13/2022] [Accepted: 09/16/2022] [Indexed: 06/16/2023]
Abstract
Simultaneously achieving efficient nitrogen (N) and phosphorus (P) removal without adding external carbon source is vital for carbon-neutral wastewater treatment. In this study, a novel cross-flow honeycomb bionic microbial carrier (CF) was developed to improve the efficiency of simultaneous nitrification, denitrification, and P removal (SNDPR) in an integrated fixed-film activated sludge (IFAS) system. A parallel laboratory-scale sequencing batch reactor with the commercialized microbial carriers (CM) (CM-IFAS) was performed as the comparative system for over 233 d The results demonstrated that CF-IFAS exhibited a more consistent N removal efficiency and better performance than CM-IFAS. In the CF-IFAS, the highest N and P removal efficiencies were 95.40% and 100%, respectively. Typical cycle analysis revealed that nitrate was primarily removed by the denitrifying glycogen-accumulating organisms in the CF-IFAS and by denitrifying phosphate-accumulating organisms in the CM-IFAS. The neutral community model showed that the microbial community assembly in both the reactors was driven by deterministic selection rather than stochastic factors. Compared to those in CM-IFAS, the microorganisms in CF-IFAS were more closely related to each other and had more keystone species: norank_f_norank_o_norank_c_OM190, SM1A02, Defluviicoccus, norank_f_ Saprospiraceae, and norank_f_Rhodocyclaceae. The absolute contents of the genes associated with N removal (bacterial amoA, archaeal amoA, NarG, NapA, NirS, and NirK) were higher in CF-IFAS than in CM-IFAS; the N cycle activity was also stronger in the CF-IFAS. Overall, the microecological environment differed between both systems. This study provides novel insights into the potential of bionic carriers to improve SNDPR performance by shaping microbial communities, thereby providing scientific guidance for practical engineering.
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Affiliation(s)
- Tong Wu
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR. China
| | - Jie Ding
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR. China
| | - Shan-Shan Yang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR. China.
| | - Le Zhong
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR. China
| | - Bing-Feng Liu
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR. China
| | - Guo-Jun Xie
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR. China
| | - Fan Yang
- School of Life Science and Technology, Harbin Institute of Technology, Harbin 150008, PR. China
| | - Ji-Wei Pang
- China Energy Conservation and Environmental Protection Group, Beijing 100089, PR. China
| | - Nan-Qi Ren
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR. China
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6
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Massoompour AR, Raie M, Borghei SM, Dewil R, Appels L. Role of carrier characteristics affecting microbial density and population in enhanced nitrogen and phosphorus removal from wastewater. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 302:113976. [PMID: 34749080 DOI: 10.1016/j.jenvman.2021.113976] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 10/16/2021] [Accepted: 10/17/2021] [Indexed: 06/13/2023]
Abstract
This research aims to improve simultaneous nitrification-denitrification and phosphorus removal (SNDPR) using novel carriers and to demonstrate the effect of carrier characteristics on nutrient removal in a biofilm reactor. For this purpose, biofilms enriched with both polyphosphate-accumulating organisms (PAOs) and nitrifiers were cultivated in two parallel sequencing batch reactors containing conventional moving bed bioreactor carriers (MBBR) and a novel type of carriers (carbon-based moving carriers (CBMC)). The new carriers were produced based on recycled waste materials via a chemical-thermal process and their specific surface area were 10.4 times higher than typical MBBR carriers of similar dimensions. The results showed that the use of CBMC carriers increased bacterial adhesion by about 18.5% and also affected the microbial population inside the biofilms, leading to an increase in PAOs abundancy and thus an increase in biological phosphorus removal up to 12.5%. Additionally, it was corroborated that the volume of the anoxic zones with dynamic behavior is strictly influenced by the carrier structure and biofilm thickness due to a limitation in oxygen penetration. Accordingly, the formation of broader anoxic zones and shrinkage of these zones to a lesser extent resulted in the continuation of anoxic reactions for longer periods using the novel carriers. Thereby, an increase in nitrogen removal by about 15% was obtained mainly by denitrifying PAOs. The results also exhibited that a higher simultaneous nitrification-denitrification (SND) efficiency can be achieved by selecting an appropriate aeration program influencing the dynamic changes of anoxic zones. Overall, a biofilm system using the new carriers, with phosphorus and nitrogen removal efficiencies of 97.5% and 92.3%, was presented as an efficient, compact, and simple operation SNDPR process.
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Affiliation(s)
- Ali Reza Massoompour
- Civil Engineering Department, Sharif University of Technology, Azadi Ave., P.O. Box. 11365-11155, Tehran, Iran.
| | - Mohammad Raie
- Civil Engineering Department, Sharif University of Technology, Azadi Ave., P.O. Box. 11365-11155, Tehran, Iran.
| | - S Mehdi Borghei
- Chemical and Petroleum Engineering Department, Sharif University of Technology, Azadi Ave., P.O. Box. 11365-11155, Tehran, Iran
| | - Raf Dewil
- KU Leuven, Department of Chemical Engineering, Process and Environmental Technology Lab, Jan Pieter De Nayerlaan 5, B-2860 Sint-Katelijne-Waver, Belgium
| | - Lise Appels
- KU Leuven, Department of Chemical Engineering, Process and Environmental Technology Lab, Jan Pieter De Nayerlaan 5, B-2860 Sint-Katelijne-Waver, Belgium
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7
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Stewart RD, Bashar R, Amstadt C, Uribe-Santos GA, McMahon KD, Seib M, Noguera DR. Pilot-scale comparison of biological nutrient removal (BNR) using intermittent and continuous ammonia-based low dissolved oxygen aeration control systems. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2022; 85:578-590. [PMID: 35100140 DOI: 10.2166/wst.2021.630] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Sensor driven aeration control strategies have recently been developed as a means to efficiently carry out biological nutrient removal (BNR) and reduce aeration costs in wastewater treatment plants. Under load-based aeration control, often implemented as ammonia-based aeration control (ABAC), airflow is regulated to meet desired effluent standards without specifically setting dissolved oxygen (DO) targets. Another approach to reduce aeration requirements is to constantly maintain low DO conditions and allow the microbial community to adapt to the low-DO environment. In this study, we compared the performance of two pilot-scale BNR treatment trains that simultaneously used ABAC and low-DO operation to evaluate the combination of these two strategies. One pilot plant was operated with continuous ABAC while the other one used intermittent ABAC. Both processes achieved greater than 90% total Kjehldal nitrogen (TKN) removal, 60% total nitrogen removal, and nearly 90% total phosphorus removal. Increasing the solids retention time (SRT) during the period of cold (∼12 °C) water temperatures helped maintain ammonia removal performance under low-DO conditions. However, both processes experienced poor solids settling characteristics during winter. While settling was recovered under warmer temperatures, improving settling quality remains a challenge under low-DO operation.
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Affiliation(s)
- Rachel D Stewart
- Department of Civil and Environmental Engineering, University of Wisconsin-Madison, Madison, WI, USA E-mail:
| | - Rania Bashar
- Department of Civil and Environmental Engineering, University of Wisconsin-Madison, Madison, WI, USA E-mail:
| | - Carly Amstadt
- Department of Civil and Environmental Engineering, University of Wisconsin-Madison, Madison, WI, USA E-mail:
| | - Gustavo A Uribe-Santos
- Department of Civil and Environmental Engineering, University of Wisconsin-Madison, Madison, WI, USA E-mail:
| | - Katherine D McMahon
- Department of Civil and Environmental Engineering, University of Wisconsin-Madison, Madison, WI, USA E-mail: ; Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, USA; Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI, USA
| | - Matt Seib
- Madison Metropolitan Sewerage District, Madison, WI, USA
| | - Daniel R Noguera
- Department of Civil and Environmental Engineering, University of Wisconsin-Madison, Madison, WI, USA E-mail: ; Wisconsin Energy Institute, University of Wisconsin-Madison, Madison, WI, USA
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8
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Rey-Martínez N, Merdan G, Guisasola A, Baeza JA. Nitrite and nitrate inhibition thresholds for a glutamate-fed bio-P sludge. CHEMOSPHERE 2021; 283:131173. [PMID: 34182653 DOI: 10.1016/j.chemosphere.2021.131173] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 04/30/2021] [Accepted: 06/06/2021] [Indexed: 06/13/2023]
Abstract
Enhanced biological phosphorus removal (EBPR) is an efficient and sustainable technology to remove phosphorus from wastewater. A widely known cause of EBPR deterioration in wastewater treatment plants (WWTPs) is the presence of nitrate/nitrite or oxygen in the anaerobic reactor. Moreover, most existing studies on the effect of either permanent aerobic conditions or inhibition of EBPR by nitrate or free nitrous acid (FNA) have been conducted with a "Candidatus Accumulibacter" or Tetrasphaera-enriched sludge, which are the two major reported groups of polyphosphate accumulating organisms (PAO) with key roles in full-scale EBPR WWTPs. This work reports the denitrification capabilities of a bio-P microbial community developed using glutamate as the sole source of carbon and nitrogen. This bio-P sludge exhibited a high denitrifying PAO (DPAO) activity, in fact, 56% of the phosphorus was uptaken under anoxic conditions. Furthermore, this mixed culture was able to use nitrite and nitrate as electron acceptor for P-uptake, being 1.8 μg HNO2-N·L-1 the maximum FNA concentration at which P-uptake can occur. Net P-removal was observed under permanent aerobic conditions. However, this microbial culture was more sensitive to FNA and permanent aerobic conditions compared to "Ca. Accumulibacter"-enriched sludge.
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Affiliation(s)
- Natalia Rey-Martínez
- GENOCOV. Departament d'Enginyeria Química, Biològica i Ambiental, Universitat Autònoma de Barcelona, Spain.
| | - Gökçe Merdan
- GENOCOV. Departament d'Enginyeria Química, Biològica i Ambiental, Universitat Autònoma de Barcelona, Spain; Department of Environmental Engineering, Namık Kemal University, Turkey.
| | - Albert Guisasola
- GENOCOV. Departament d'Enginyeria Química, Biològica i Ambiental, Universitat Autònoma de Barcelona, Spain.
| | - Juan Antonio Baeza
- GENOCOV. Departament d'Enginyeria Química, Biològica i Ambiental, Universitat Autònoma de Barcelona, Spain.
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Rout PR, Shahid MK, Dash RR, Bhunia P, Liu D, Varjani S, Zhang TC, Surampalli RY. Nutrient removal from domestic wastewater: A comprehensive review on conventional and advanced technologies. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 296:113246. [PMID: 34271353 DOI: 10.1016/j.jenvman.2021.113246] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 06/13/2021] [Accepted: 07/07/2021] [Indexed: 05/06/2023]
Abstract
Nitrogen and phosphorous are indispensable for growth and vitality of living beings, hence termed as nutrients. However, discharge of nutrient rich waste streams to aquatic ecosystems results in eutrophication. Therefore, nutrient removal from wastewater is crucial to meet the strict nutrient discharge standards. Similarly, nutrient recovery from waste streams is vital for the realization of a circular economy by avoiding the depletion of finite resources. This manuscript presents analysis of existing information on different conventional as well as advanced treatment technologies that are commonly practiced for the removal of nutrient from domestic wastewater. First, the information pertaining to the biological nutrient removal technologies are discussed. Second, onsite passive nutrient removal technologies are reviewed comprehensively. Third, advanced nutrient removal technologies are summarized briefly. The mechanisms, advantages, and disadvantages of these technologies along with their efficiencies and limitations are discussed. An integrated approach for simultaneous nutrient removal and recovery is recommended. The fifth section of the review highlights bottlenecks and potential solutions for successful implementation of the nutrient removal technologies. It is anticipated that the review will offer an instructive overview of the progress in nutrient removal and recovery technologies and will illustrate necessity of further investigations for development of efficient nutrient removal and recovery processes.
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Affiliation(s)
- Prangya Ranjan Rout
- Department of Biotechnology, Thapar Institute of Engineering and Technology, Patiala, India
| | - Muhammad Kashif Shahid
- Department of Environmental Engineering, Chungnam National University, Republic of Korea
| | - Rajesh Roshan Dash
- School of Infrastructure, Indian Institute of Technology Bhubaneswar, India
| | - Puspendu Bhunia
- School of Infrastructure, Indian Institute of Technology Bhubaneswar, India
| | - Dezhao Liu
- College of Biosystems Engineering and Food Science, Zhejiang University, China
| | - Sunita Varjani
- Gujarat Pollution Control Board, Gandhinagar, 382 010, Gujarat, India.
| | - Tian C Zhang
- Department of Civil and Environmental Engineering, University of Nebraska-Lincoln, Omaha, NE, 68182, USA
| | - Rao Y Surampalli
- Global Institute for Energy, Environment and Sustainability, Kansas, USA
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10
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Zhu GC, Lu YZ, Xu LR. Effects of the carbon/nitrogen (C/N) ratio on a system coupling simultaneous nitrification and denitrification (SND) and denitrifying phosphorus removal (DPR). ENVIRONMENTAL TECHNOLOGY 2021; 42:3048-3054. [PMID: 31969084 DOI: 10.1080/09593330.2020.1720310] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2019] [Accepted: 01/17/2020] [Indexed: 06/10/2023]
Abstract
Simultaneous nitrification and denitrification (SND) were coupled with a denitrifying phosphorus removal (DPR) to achieve simultaneous nutrient and carbon removal. With influent chemical oxygen demand (COD), ammonia-N (NH4+-N), and total phosphorus (TP) concentrations of 250, 50, and 8 mg/L, the SND-DPR coupled system achieved stable nutrient removal efficiency of COD, NH4+-N, TN and TP were 91.8 ± 1.7%, 88.4 ± 1.8%, 64 ± 3.3% and 99.2 ± 0.6%, respectively. Enhancing the C/N ratio strengthened the storage of intracellular polymers and provided sufficient intracellular carbon sources for phosphorus uptake. The nutrient removal efficiency reached the highest level at a C/N ratio of 5, and no advantage was observed after increasing the C/N ratio to 7. Nutrients were mainly removed during the aerobic stage at a low DO concentration as well during the anoxic stage, which helped achieve concurrent nitrification and denitrification by ordinary heterotrophic organisms (OHOs), promote denitrifying and aerobic phosphorus removal, and conserve organic carbon demand and energy consumption for aeration. The system was limited for DO in the aerobic stage at a low DO concentration, resulting in a deficiency in electron acceptors (O2 and NO3-N) and limiting the subsequent promotion of phosphorus uptake and TN removal. The limited DO content in the low DO stage was the key factor involved in enhancing the nutrient removal efficiency along with the increasing influent C/N ratio.
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Affiliation(s)
- Guang-Can Zhu
- School of Energy and Environment, Key Laboratory of Environmental Medicine Engineering, Ministry of Education, Southeast University, Nanjing, Jiangsu 210096, People's Republic of China
| | - Yong-Ze Lu
- School of Energy and Environment, Key Laboratory of Environmental Medicine Engineering, Ministry of Education, Southeast University, Nanjing, Jiangsu 210096, People's Republic of China
| | - Li-Ran Xu
- School of Energy and Environment, Key Laboratory of Environmental Medicine Engineering, Ministry of Education, Southeast University, Nanjing, Jiangsu 210096, People's Republic of China
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Izadi P, Izadi P, Eldyasti A. A review of biochemical diversity and metabolic modeling of EBPR process under specific environmental conditions and carbon source availability. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 288:112362. [PMID: 33831633 DOI: 10.1016/j.jenvman.2021.112362] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 02/25/2021] [Accepted: 03/09/2021] [Indexed: 05/25/2023]
Abstract
Enhanced biological phosphorus removal (EBPR) is one of the most promising technologies as an economical and environmentally sustainable technique for removal of phosphorus from wastewater (WW). However, with high capacity of EBPR, insufficient P-removal is a major yet common issue of many full-scale wastewater treatment plants (WWTP), due to misinterpreted environmental and microbial disturbance. By developing a rather extensive understanding on biochemical pathways and metabolic models governing the anaerobic and aerobic/anoxic processes; the optimal operational conditions, environmental changes and microbial population interaction are efficiently predicted. Therefore, this paper critically reviews the current knowledge on biochemical pathways and metabolic models of phosphorus accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs) as the most abundant microbial populations in EBPR process with an insight on the effect of available carbon source types in WW on phosphorus removal performance. Moreover, this paper critically assesses the gaps and potential future research in metabolic modeling area. With all the developments on EBPR process in the past few decades, there is still lack of knowledge in this critical sector. This paper hopes to touch on this problem by gathering the existing knowledge and to provide farther insights on the future work onto chemical transformations and metabolic strategies in different conditions to benefit the quantitative model as well as WWTP designs.
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Affiliation(s)
- Parnian Izadi
- Civil engineering, York university, 4700 Keele St, Toronto, M3J 1P3, ON, Canada.
| | - Parin Izadi
- Civil engineering, York university, 4700 Keele St, Toronto, M3J 1P3, ON, Canada.
| | - Ahmed Eldyasti
- Civil engineering, York university, 4700 Keele St, Toronto, M3J 1P3, ON, Canada.
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12
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Yuan C, Wang B, Peng Y, Li X, Zhang Q. Simultaneous enhanced biological phosphorus removal and semi-nitritation (EBPR-SN) followed by anammox process treating municipal wastewater at seasonal temperatures: From summer to winter. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 757:144048. [PMID: 33316517 DOI: 10.1016/j.scitotenv.2020.144048] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Revised: 11/16/2020] [Accepted: 11/19/2020] [Indexed: 06/12/2023]
Abstract
This work investigated the feasibility of a novel simultaneous enhanced biological phosphorus removal and semi-nitritation (EBPR-SN) plus anammox process treating real municipal wastewater from summer to winter (28.1- 15.3 °C). Two lab-scale sequential reactors were used in this study, namely EBPR-SN and Anammox sequencing batch reactors (SBRs). Long-term operation suggested that ammonium oxidizing bacteria abundance decreased from 1.67% to 0.89% whereas nitrite oxidizing bacteria decreased to nearly undetected in the EBPR-SN SBR, maintaining the stable nitritation (nitrite accumulation ratio: 98.3 ± 1.0%). Lowering airflow rate was effective to retain nitritation with temperature decrease. Reliable nutrient removal was still maintained in winter (16.4 ± 0.7 °C), i.e. the removal efficiencies for nitrogen and phosphorus were 80.0 ± 3.5% and 95.4 ± 5.2%, respectively, with short aerobic HRT (6.4 h) and low dissolved oxygen (0.2-1.5 mg/L). The percentage of anammox contribution to nitrogen-removal increased with temperature decrease, although Candidatus Brocadia abundance decreased. Additionally, the protection of extracellular polymeric substances was important to the successful performance.
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Affiliation(s)
- Chuansheng Yuan
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China
| | - Bo Wang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China.
| | - Xiyao Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China
| | - Qiong Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China
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13
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Roy S, Guanglei Q, Zuniga-Montanez R, Williams RB, Wuertz S. Recent advances in understanding the ecophysiology of enhanced biological phosphorus removal. Curr Opin Biotechnol 2021; 67:166-174. [PMID: 33582603 DOI: 10.1016/j.copbio.2021.01.011] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 01/11/2021] [Accepted: 01/12/2021] [Indexed: 01/02/2023]
Abstract
Enhanced biological phosphorus removal (EBPR) is an efficient, cost-effective, and sustainable method for removing excess phosphorus from wastewater. Polyphosphate accumulating organisms (PAOs) exhibit a unique physiology alternating between anaerobic conditions for uptake of carbon substrates and aerobic or anoxic conditions for phosphorus uptake. The implementation of high-throughput sequencing technologies and advanced molecular tools along with biochemical characterization has provided many new perspectives on the EBPR process. These approaches have helped identify a wide range of carbon substrates and electron acceptors utilized by PAOs that in turn influence interactions with microbial community members and determine overall phosphorus removal efficiency. In this review, we systematically discuss the microbial diversity and metabolic response to a range of environmental conditions and process control strategies in EBPR.
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Affiliation(s)
- Samarpita Roy
- Singapore Centre for Environmental Life Sciences Engineering, National University of Singapore, Singapore 119077, Singapore
| | - Qiu Guanglei
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Rogelio Zuniga-Montanez
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore 637551, Singapore; Department of Civil and Environmental Engineering, University of California, One Shields Avenue, Davis, CA 95616, United States
| | - Rohan Bh Williams
- Singapore Centre for Environmental Life Sciences Engineering, National University of Singapore, Singapore 119077, Singapore
| | - Stefan Wuertz
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore 637551, Singapore; Department of Civil and Environmental Engineering, University of California, One Shields Avenue, Davis, CA 95616, United States; School of Civil and Environmental Engineering, Nanyang Technological University, Singapore 639798, Singapore.
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14
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Majed N, Gu AZ. Phenotypic dynamics in polyphosphate and glycogen accumulating organisms in response to varying influent C/P ratios in EBPR systems. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 743:140603. [PMID: 32758819 DOI: 10.1016/j.scitotenv.2020.140603] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 06/17/2020] [Accepted: 06/27/2020] [Indexed: 06/11/2023]
Abstract
This study employed molecular tools and single cell Raman micro-spectroscopy techniques to reveal the single cell- and population-level phenotypic dynamics and changes in functionally relevant organisms, namely polyphosphate accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs), in response to influent loading readily biodegradable carbon to phosphorus ratio (C/P) changes in enhanced biological phosphorus removal (EBPR) systems. The results, for the first time, provided direct and cellular evidence confirming the adaptive anaerobic metabolic pathway shifts in PAOs in response to influent loading variations. Increase in influent readily biodegradable carbon to phosphorus (C/P) ratio from 20 to 50 led to nearly 50% decline in polyphosphate content and drastic rise of intracellular polyβhydroxybutyrate (PHB) to polyphosphate (polyP) ratio by nearly 6 times in PAOs, indicating corresponding diminishing reliance on polyP hydrolysis for energy as P becomes limiting. Influent carbon availability surge also impacted the intracellular carbon polymers in GAOs, with significant increase in the mean PHB content level but no observed changes in the intracellular glycogen level. Furthermore, the Raman-based quantification of differentiated intracellular polymer content associated with PAOs and GAOs, revealed new insights into the quantitative shift in intracellular carbon storage distribution between the two populations and their variations between the two carbon polymers (PHB, Glycogen). In summary, this investigation revealed high-resolution cellular level information regarding the metabolic flexibility in PAOs, phenotypic stoichiometry changes and carbon flux and distribution among PAOs and GAOs, in response to influent loading conditions. The new information will contribute to improvement in mechanistic EBPR modeling and design.
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Affiliation(s)
- Nehreen Majed
- Department of Civil Engineering, University of Asia Pacific, 74/A Green Road, Dhaka 1205, Bangladesh; Department of Civil & Environmental Engineering, Northeastern University, 360 Huntington Avenue, Boston, MA 02115, USA.
| | - April Z Gu
- Department of Civil & Environmental Engineering, Northeastern University, 360 Huntington Avenue, Boston, MA 02115, USA.
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15
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Sun Y, Peng Y, Zhang J, Li X, Zhang Q, Zhang L. Effect of endogenous metabolisms on survival and activities of denitrifying phosphorus removal sludge under various starvation conditions. BIORESOURCE TECHNOLOGY 2020; 315:123839. [PMID: 32731158 DOI: 10.1016/j.biortech.2020.123839] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 07/08/2020] [Accepted: 07/10/2020] [Indexed: 06/11/2023]
Abstract
Denitrifying phosphorus removal sludge are usually faced with various famine environments in wastewater treatment plants (WWTPs). Endogenous metabolisms under aerobic, anoxic, and anaerobic starved conditions were characterized to investigate their impact on survival and activities of denitrifying polyphosphate accumulating organisms (DPAOs). DPAOs utilized intracellular polymers to survive and presented diverse consumed priorities of PHA types under various starvations. The biomass decay rate was approximately 2.7 and 1.7 times lower for aerobic condition than for anoxic and anaerobic conditions owing to the maximum maintenance energy requirement for aerobic condition (68.6 mmol/C-molVSS ATP). During short-term starvations, significant activity decay for anaerobic starved sludge was attributed to its distinctive endogenous metabolisms. For long-term starvations, the higher amounts and preponderant type of PHA (PHB) reserve favored to the greater DPAO activities for anoxic starved sludge. The results show that anoxic condition may be an implementable strategy for maintaining denitrifying phosphorus removal performance in WWTPs.
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Affiliation(s)
- Yawen Sun
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China.
| | - Jianhua Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Xiyao Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Qiong Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Liang Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
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16
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Yuan C, Peng Y, Wang B, Li X, Zhang Q. Facilitating sludge granulation and favoring glycogen accumulating organisms by increased salinity in an anaerobic/micro-aerobic simultaneous partial nitrification, denitrification and phosphorus removal (SPNDPR) process. BIORESOURCE TECHNOLOGY 2020; 313:123698. [PMID: 32585454 DOI: 10.1016/j.biortech.2020.123698] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 06/11/2020] [Accepted: 06/13/2020] [Indexed: 06/11/2023]
Abstract
This study used salinity (0.5 wt%, 0.75 wt%) to accelerate the formation of ammonia oxidizing bacteria (AOB)-enriched aerobic granular sludge in a lab-scale anaerobic/micro-aerobic simultaneous partial nitrification, denitrification and phosphorus removal (SPNDPR) reactor. Results confirmed that the average granule diameter increased from 298.7 to 425.4 µm after 45 days of salinity stress even with low dissolved oxygen. Extracellular polymeric substances increased from 149.5 to 387.7 mg/g VSS after salinity (0.75 wt%) treatment, in turn accelerating granulation. Partial nitrification was maintained under the salinity condition due to the relative high activity and abundance of AOB, and the observed nitrite accumulation ratio averaged 98.9%. Salinity favored glycogen-accumulating organisms over polyphosphate-accumulating organisms (PAOs)/denitrifying-PAOs, with the abundance of Candidatus_Competibacter increasing from 4.86% to 15.34% and the simultaneous partial nitrification-denitrification efficiency increasing from 74.4% to 91.1%, promoting N-removal potential. The P-removal performance was good under 0.5 wt% salinity but was inhibited under 0.75 wt% salinity.
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Affiliation(s)
- Chuansheng Yuan
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China.
| | - Bo Wang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China
| | - Xiyao Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China
| | - Qiong Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China
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17
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Yuan C, Wang B, Peng Y, Li X, Zhang Q, Hu T. Enhanced nutrient removal of simultaneous partial nitrification, denitrification and phosphorus removal (SPNDPR) in a single-stage anaerobic/micro-aerobic sequencing batch reactor for treating real sewage with low carbon/nitrogen. CHEMOSPHERE 2020; 257:127097. [PMID: 32470541 DOI: 10.1016/j.chemosphere.2020.127097] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2020] [Revised: 04/26/2020] [Accepted: 05/15/2020] [Indexed: 05/25/2023]
Abstract
The feasibility of simultaneous partial nitrification, denitrification and phosphorus removal (SPNDPR) process was investigated in a single-stage anaerobic/micro-aerobic sequencing batch reactor for treating real sewage. Partial nitrification was maintained with average nitrite accumulation ratio of 90.3% during 266 days' operation. Removal efficiencies for NH4+-N (96.3%), total inorganic nitrogen (81.4%), and phosphorus (91.0%) were stably obtained when treated real sewage with low carbon/nitrogen (3.4), with simultaneous partial nitrification and denitrification efficiency of 73.1%. The mechanism analysis revealed that denitrifying glycogen-accumulating organisms (DGAOs) and denitrifying polyphosphate-accumulating organisms (DPAOs) played the main roles in N-removal and P-removal, respectively. Nitrite pathway and optimized use of the organic carbon available in the sewage were keys for the successful performance. Further microbial community illustrating that DGAOs Candidatus_Competibacter, DPAOs Dechloromonas, and ammonia-oxidizing bacteria Nitrosomonadaceae were main functional groups. Notably, sludge granulation was formed under long-term synchronous low dissolved oxygen and low sludge loading conditions, avoiding sludge bulking.
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Affiliation(s)
- Chuansheng Yuan
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing, 100124, China
| | - Bo Wang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing, 100124, China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing, 100124, China.
| | - Xiyao Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing, 100124, China
| | - Qiong Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing, 100124, China
| | - Tiantian Hu
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing, 100124, China
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18
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Daly I, Jellali S, Mehri I, Reis MAM, Freitas EB, Oehmen A, Chatti A. Phosphorus and ammonium removal characteristics from aqueous solutions by a newly isolated plant growth-promoting bacterium. ENVIRONMENTAL TECHNOLOGY 2020; 41:2603-2617. [PMID: 30689524 DOI: 10.1080/09593330.2019.1575917] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 01/19/2019] [Indexed: 06/09/2023]
Abstract
An indigenous plant growth-promoting bacterium isolated from Peganum Harmala rhizosphere in the arid ecosystem was found to solubilize and accumulate phosphates. This isolate was identified as Pseudomonas sp. (PHR6) by partial 16S rRNA gene sequence analysis. Controlled batch experiments on nutrients removal by this isolate in mineral medium showed relatively high efficiencies after 24 h of aerobic incubation with average values of 117.59 and 335.38 mg gVSS-1 for phosphorus (P-PO4) and nitrogen (N-NH4), respectively. Furthermore, the strain performed heterotrophic nitrification ranging from 48.81% to 84.24% of the total removed nitrogen. On the other hand, the experimental results showed that a short idle period (24 h) significantly enhanced P accumulation (up to 95%) and N assimilation (up to 50%) of the total removed amounts. However, long idle period (20 days) revealed firstly aerobic phosphorous release phase succeeded by another removal one within 24 h of incubation. Overall, the idle treatment enhances P removal efficiency from the mineral liquid medium without significant effects on N-NH4 removal performance. The isolated strain showed also significant nutrient removal ability from synthetic wastewater providing an accumulated fraction of 98% from the total removed phosphorus amount. This study highlights the potential contribution of the selected rhizobacterium PHR6 to both environmental nutrient recycling and pollution control especially regarding phosphorus.
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Affiliation(s)
- Imen Daly
- Wastewaters and Environment Laboratory (LabEauE), Water Research and Technologies Center, Technopark of Borj-Cedria, Soliman, Tunisia
- Faculty of Sciences of Tunis, Tunis El Manar University, El-Manar II, Tunisia
| | - Salah Jellali
- Wastewaters and Environment Laboratory (LabEauE), Water Research and Technologies Center, Technopark of Borj-Cedria, Soliman, Tunisia
| | - Ines Mehri
- Laboratory of Treatment and Valorization of Water Rejects (LTVRH), Water Research and Technologies Center, Technopark of Borj-Cedria, Soliman, Tunisia
| | - Maria A M Reis
- Faculty of Sciences and Technology, Chemistry Department, FCT-UNL, Caparica, Portugal
| | - Elisabete B Freitas
- Faculty of Sciences and Technology, Chemistry Department, FCT-UNL, Caparica, Portugal
| | - Adrian Oehmen
- Faculty of Sciences and Technology, Chemistry Department, FCT-UNL, Caparica, Portugal
| | - Abdelwaheb Chatti
- Laboratory of Treatment and Valorization of Water Rejects (LTVRH), Water Research and Technologies Center, Technopark of Borj-Cedria, Soliman, Tunisia
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19
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Xu X, Zhong P, Zhang C, Yuan L, Sun G, Qian Y, Liang H. Improved membrane sequencing batch reactor: effect of carbon and nitrogen volumetric loading rate on dephosphatation. ENVIRONMENTAL TECHNOLOGY 2020; 41:1401-1410. [PMID: 30336743 DOI: 10.1080/09593330.2018.1537304] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 10/13/2018] [Indexed: 06/08/2023]
Abstract
A lab-scale anaerobic-anoxic-aerobic membrane bioreactor (A2NO-MBR) fed with synthetic wastewater was operated to investigate the impact of influent carbon and nitrogen volumetric loading rate (VLR) on dephosphatation, and the corresponding influent concentration was 100-300 mg L-1 (COD), 24-50 mg L-1 (NH4+-N) and 4.8-6.0 mg L-1 (TP), respectively. The results demonstrated that carbon VLR had a negligible effect on the COD removal with effluent below 50 mg L-1, and high and stable removal capacity for phosphorus were also obtained, regardless of carbon VLR change. Whereas TN removal efficiency was positively correlated with carbon VLR reduction, and lower carbon VLR produced a negative effect on TN removal. In addition, since nitrate served as an electron acceptor for denitrifying phosphorus removal (DPR), a significant effect on nitrogen and phosphorus removal was observed with different nitrogen VLR. The TN and TP removal efficiency was 68.30 ± 1.36%, 70.70 ± 1.23%, 45.19 ± 1.72% and 41.63 ± 3.09%, 98.14 ± 0.53%, 53.34 ± 2.68% with influent nitrogen VLR of 0.024 ± 0.001, 0.034 ± 0.001 and 0.045 ± 0.001 kg-N/(m3 d), respectively. Moreover, bacterial community structure of sludge samples in Run I and V from anaerobic-anoxic-aerobic-SBR (named A2OSBR_1 and A2OSBR_2) and membrane bioreactor (named N-MBR_1 and N-MBR_2) revealed that Candidatus_Accumulibacter was the most dominant genus in A2OSBR_1 (21.50%) and A2OSBR_2 (18.98%). The relative lower carbon VLR favoured the enrichment of Saprospiraceae, which was related with DPR, with the proportion of 9.31% and 14.61% in A2OSBR_1 and A2OSBR_2. Besides, Nitrospira and Nitrosomonas with proportions of 11.14%, 5.38% in N-MBR_1 and 10.72%, 6.77% in N-MBR_2 were observed, which were likely responsible for the nearly complete nitrification.
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Affiliation(s)
- Xinhai Xu
- School of Environment and Spatial Informatics, China University of Mining and Technology, Xuzhou, People's Republic of China
| | - Peilin Zhong
- School of Environment and Spatial Informatics, China University of Mining and Technology, Xuzhou, People's Republic of China
| | - Chuanyi Zhang
- School of Environment and Spatial Informatics, China University of Mining and Technology, Xuzhou, People's Republic of China
| | - Limei Yuan
- School of Environment and Spatial Informatics, China University of Mining and Technology, Xuzhou, People's Republic of China
| | - Guangrong Sun
- School of Environment and Spatial Informatics, China University of Mining and Technology, Xuzhou, People's Republic of China
| | - Yunkun Qian
- School of Environment and Spatial Informatics, China University of Mining and Technology, Xuzhou, People's Republic of China
| | - Hai Liang
- School of Environment and Spatial Informatics, China University of Mining and Technology, Xuzhou, People's Republic of China
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20
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Wang S, Li Z, Wang D, Li Y, Sun L. Performance and population structure of two carbon sources granular enhanced biological phosphorus removal systems at low temperature. BIORESOURCE TECHNOLOGY 2020; 300:122683. [PMID: 31901772 DOI: 10.1016/j.biortech.2019.122683] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 12/21/2019] [Accepted: 12/23/2019] [Indexed: 06/10/2023]
Abstract
This study explored the effect of two carbon sources on performance and population structure of granular enhanced biological phosphorus removal systems at long-term low temperature by using two sequencing batch reactors, with acetate (SBR-1) and propionate (SBR-2) as carbon sources respectively. Results showed that highly efficient EBPR were successfully achieved, and the average PO43--P and COD removal efficiency of SBR-1 and SBR-2 were 94.2%, 87.1% and 98.2%, 87.0%, respectively. Moreover, the acetate system preferred to utilize intracellular Mg/K-polyP to produce ATP for VFA uptake rather than glycogen. High-throughput sequencing analysis revealed that the abundance of Rhodocyclaceae were 31.7% (SBR-1) and 71.7% (SBR-2), and genus Dechloromonas was enriched to 60.5% with propionate, evidently higher than acetate (1.2%). Furthermore, in addition to oxygen, Dechloromonas could use nitrate as electron acceptors for phosphate uptake. The study further provides support to simultaneous nitrogen and phosphorus removal at low temperature.
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Affiliation(s)
- Shaopo Wang
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Jinjing Road 26, Tianjin 300384, China; Tianjin Key Laboratory of Aquatic Science and Technology, Jinjing Road 26, Tianjin, China; Joint Research Centre for Protective Infrastructure Technology and Environmental Green Bioprocess, School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, China.
| | - Zhu Li
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Jinjing Road 26, Tianjin 300384, China; Tianjin Key Laboratory of Aquatic Science and Technology, Jinjing Road 26, Tianjin, China; Joint Research Centre for Protective Infrastructure Technology and Environmental Green Bioprocess, School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, China
| | - Dong Wang
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Jinjing Road 26, Tianjin 300384, China; Tianjin Key Laboratory of Aquatic Science and Technology, Jinjing Road 26, Tianjin, China; Joint Research Centre for Protective Infrastructure Technology and Environmental Green Bioprocess, School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, China
| | - Yajing Li
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Jinjing Road 26, Tianjin 300384, China; Tianjin Key Laboratory of Aquatic Science and Technology, Jinjing Road 26, Tianjin, China; Joint Research Centre for Protective Infrastructure Technology and Environmental Green Bioprocess, School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, China
| | - Liping Sun
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Jinjing Road 26, Tianjin 300384, China; Tianjin Key Laboratory of Aquatic Science and Technology, Jinjing Road 26, Tianjin, China; Joint Research Centre for Protective Infrastructure Technology and Environmental Green Bioprocess, School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, China
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21
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Optimization of Wastewater Phosphorus Removal in Winter Temperatures Using an Anaerobic–Critical Aerobic Strategy in a Pilot-Scale Sequencing Batch Reactor. WATER 2019. [DOI: 10.3390/w12010110] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Biological phosphorus removal using an anaerobic–aerobic sequencing batch reactor (SBR) in a low temperature can be difficult to remove, and aeration always accounts for nearly half of the total electricity costs at many wastewater treatment plants. In this study, a pilot-scale anaerobic–critical aerobic SBR (A–CA SBR) was developed for synthetic domestic wastewater. More importantly, the phase, whose concentration of diffused oxygen was controlled at 1.0–1.5 mg/L, was defined as a critical aerobic phase, which reduced expenses during the operation. To be specific, half of the ammonia was removed within 10 days and no NO3−–N was accumulated during the process. From the SEM and metagenome analysis, Rhodocyclus, Zooglea, Dechloromonas, and Simplicispira had the ability to remove phosphorus and NO3−–N simultaneously, which proved the existence of a potential double-layer sludge structure under an A–CA operational condition. All of the results disclose that the pilot-scale A–CA SBR is a reliable manipulation strategy for phosphorus removal under low temperatures, which can hopefully apply to practical wastewater remediation.
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22
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Nguyen Quang M, Rogers T, Hofman J, Lanham AB. Global Sensitivity Analysis of Metabolic Models for Phosphorus Accumulating Organisms in Enhanced Biological Phosphorus Removal. Front Bioeng Biotechnol 2019; 7:234. [PMID: 31637235 PMCID: PMC6787149 DOI: 10.3389/fbioe.2019.00234] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 09/09/2019] [Indexed: 11/23/2022] Open
Abstract
The aim of this study was to identify, quantify and prioritize for the first time the sources of uncertainty in a mechanistic model describing the anaerobic-aerobic metabolism of phosphorus accumulating organisms (PAO) in enhanced biological phosphorus removal (EBPR) systems. These wastewater treatment systems play an important role in preventing eutrophication and metabolic models provide an advanced tool for improving their stability via system design, monitoring and prediction. To this end, a global sensitivity analysis was conducted using standard regression coefficients and Sobol sensitivity indices, taking into account the effect of 39 input parameters on 10 output variables. Input uncertainty was characterized with data in the literature and propagated to the output using the Monte Carlo method. The low degree of linearity between input parameters and model outputs showed that model simplification by linearization can be pursued only in very well defined circumstances. Differences between first and total-order sensitivity indices showed that variance in model predictions was due to interactions between combinations of inputs, as opposed to the direct effect of individual inputs. The major sources of uncertainty affecting the prediction of liquid phase concentrations, as well as intra-cellular glycogen and poly-phosphate was due to 64% of the input parameters. In contrast, the contribution to variance in intra-cellular PHA constituents was uniformly distributed among all inputs. In addition to the intra-cellular biomass constituents, notably PHB, PH2MV and glycogen, uncertainty with respect to input parameters directly related to anaerobic propionate uptake, aerobic poly-phosphate formation, glycogen formation and temperature contributed most to the variance of all model outputs. Based on the distribution of total-order sensitivities, characterization of the influent stream and intra-cellular fractions of PHA can be expected to significantly improve model reliability. The variance of EBPR metabolic model predictions was quantified. The means to account for this variance, with respect to each quantity of interest, given knowledge of the corresponding input uncertainties, was prescribed. On this basis, possible avenues and pre-requisite requirements to simplify EBPR metabolic models for PAO, both structurally via linearization, as well as by reduction of the number of non-influential variables were outlined.
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Affiliation(s)
- Minh Nguyen Quang
- Department of Chemical Engineering, Water Innovation and Research Centre, University of Bath, Bath, United Kingdom
| | - Tim Rogers
- Department of Mathematical Sciences, Centre for Networks and Collective Behaviour, University of Bath, Bath, United Kingdom
| | - Jan Hofman
- Department of Chemical Engineering, Water Innovation and Research Centre, University of Bath, Bath, United Kingdom
| | - Ana B Lanham
- Department of Chemical Engineering, Water Innovation and Research Centre, University of Bath, Bath, United Kingdom
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Yun G, Lee H, Hong Y, Kim S, Daigger GT, Yun Z. The difference of morphological characteristics and population structure in PAO and DPAOgranular sludges. J Environ Sci (China) 2019; 76:388-402. [PMID: 30528031 DOI: 10.1016/j.jes.2018.06.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Revised: 06/05/2018] [Accepted: 06/05/2018] [Indexed: 06/09/2023]
Abstract
We examined how long-term operation of anaerobic-oxic and anaerobic-anoxic sequencing batch reactors (SBRs) affects the enhanced biological phosphorus removal (EBPR) performance and sludge characteristics. The microbial characteristics of phosphorus accumulating organism (PAO) and denitrifying PAO (DPAO) sludge were also analyzed through a quantitative analysis of microbial community structure. Compared with the initial stage of operation characterized by unstable EBPR, both PAO and DPAO SBR produced a stable EBPR performance after about 100-day operation. From day 200 days (DPAO SBR) and 250 days (PAO SBR) onward, sludge granulation was observed, and the average granule size of DPAO SBR was approximately 5 times larger than that of PAO SBR. The DPAO granular sludge contained mainly rod-type microbes, whereas the PAO granular sludge contained coccus-type microbes. Fluorescence in situ hybridization analysis revealed that a high ratio of Accumulibacter clade I was found only in DPAO SBR, revealing the important role of this organism in the denitrifying EBPR system. A pyrosequencing analysis showed that Accumulibacter phosphatis was present in PAO sludge at a high proportion of 6%, whereas it rarely observed in DPAO sludge. Dechloromonas was observed in both PAO sludge (3.3%) and DPAO sludge (3.2%), confirming that this organism can use both O2 and NO3- as electron acceptors. Further, Thauera spp. was identified to have a new possibility as denitrifier capable of phosphorous uptake under anoxic condition.
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Affiliation(s)
- Geumhee Yun
- Department of Environmental Engineering, Korea University, Sejong, 339-700, South Korea.
| | - Hansaem Lee
- Hyundai Engineering & Construction Co., Ltd., 17-6 Mabuk-Ro 240, Giheung-Gu, Yongin-Si, Gyuonggi-Do, South Korea
| | - Yongsuk Hong
- Department of Environmental Engineering, Korea University, Sejong, 339-700, South Korea
| | - Sungpyo Kim
- Department of Environmental Engineering, Korea University, Sejong, 339-700, South Korea
| | - Glen T Daigger
- Department of Civil and Environmental Engineering, University of Michigan, 177 EWRE Building, 1351 Beal Avenue, Ann Arbor, MI 48109-2125, USA
| | - Zuwhan Yun
- Department of Environmental Engineering, Korea University, Sejong, 339-700, South Korea.
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Fudala-Ksiazek S, Kulbat E, Luczkiewicz A. Nitrification, denitrification, and dephosphatation capability of activated sludge during co-treatment of intermediate-age landfill leachates with municipal wastewater. ENVIRONMENTAL TECHNOLOGY 2018; 39:986-996. [PMID: 28394206 DOI: 10.1080/09593330.2017.1317842] [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: 10/27/2016] [Accepted: 04/04/2017] [Indexed: 06/07/2023]
Abstract
UNLABELLED This study focuses on the possible use and efficacy of the co-treatment of landfill leachate (intermediate-age) with municipal wastewater. The nitrification, denitrification, and dephosphatation capability of activated sludge acclimated with a mixture of raw municipal wastewater (RWW) with gradually increasing amounts of raw landfill leachate (RLL) (from 0.5 to 5% v/v) were tested. Biochemical tests were conducted simultaneously in batch reactors (BRs). According to the obtained data, the ammonia utilization rate (AUR) was 3.68 g N/(kg volatile suspended solids (VSS)·h) for RWW, and it increased to 5.78 g N/(kg VSS·h) with the addition of 5% RLL. The nitrate utilization rate under anoxic conditions (NURAX) remained at a comparable level of 1.55-1.98 g N/(kg VSS·h). During the anoxic phase, both nitrate utilization and phosphorus uptake occurred, suggesting that denitrifying phosphorus-accumulating organisms (DPAOs) utilized N-NO3. With the addition of RLL, the rates of anoxic and aerobic phosphate uptake (PURAX and PURAE) and phosphate release rate (PRR) decreased. The PRR was likely negatively influenced by high N-NO3 concentrations but not completely inhibited due to the availability of a biodegradable fraction of chemical oxygen demand (COD). Thus, monitoring the NH4-N load in wastewater treatment plant influent before co-treatment is more informative than that using hydraulic-based criteria. ABBREVIATIONS σ - standard deviation; AUR - ammonia utilization rate; DPAO - denitrifying phosphorus-accumulating organisms; MLVSS - mixed liquor volatile suspended solids content; MSW - municipal solid waste; NURAE - nitrate production rate under aerobic conditions; NURAX - nitrate utilization rate under anoxic conditions; PAO - phosphorus-accumulating organisms; PRR - phosphate release rate under anaerobic conditions; PURAX - phosphate uptake rate under anoxic conditions; PURAE - phosphate uptake rate under aerobic conditions; RLL - raw landfill leachates; RM0.5 - raw mixture of RWW with 0.5% (vol.) of RLL; RM3 - raw mixture of RWW with 3% (vol.) of RLL; RM5 - raw mixture of RWW with 5% (vol.) of RLL; RWW - wastewater; VFA - volatile fatty acids; WWTP - wastewater treatment plant.
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Affiliation(s)
- S Fudala-Ksiazek
- a Faculty of Civil and Environmental Engineering, Department of Sanitary Engineering , Gdansk University of Technology , Gdansk , Poland
| | - E Kulbat
- b Faculty of Civil and Environmental Engineering, Department of Water and Wastewater Technology , Gdansk University of Technology , Gdansk , Poland
| | - A Luczkiewicz
- b Faculty of Civil and Environmental Engineering, Department of Water and Wastewater Technology , Gdansk University of Technology , Gdansk , Poland
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Dai H, Lu X, Peng L, Li X, Dai Z. Enrichment culture of denitrifying phosphorus removal sludge and its microbial community analysis. ENVIRONMENTAL TECHNOLOGY 2017; 38:2800-2810. [PMID: 28041535 DOI: 10.1080/09593330.2016.1278276] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 12/28/2016] [Indexed: 06/06/2023]
Abstract
An efficient one-step domestication method with mixed electron acceptors and short-time post-aeration was developed for the enrichment culture of denitrifying phosphorus removal sludge. The acclimation time, performance of nitrogen and phosphorus simultaneous removal and microbial community structure were investigated to reveal the difference among the obtained phosphorus removal sludge using different acclimation ways. Results showed that the proposed method with optimal proportion of nitrite and nitrate could significantly shorten domestication time (28 days) compared with the traditional two-step method (60 days), but exerted nearly no influence on the removal efficiency of nitrogen and phosphorus. High-throughput sequencing revealed that similar microbial community structure of DPAOs sludge was obtained with different acclimation methods. Compared with seed sludge, microbial community shifted obviously, and the dominant microbial population of Dechloromonas-related phosphorus removal bacteria increased significantly. It could be inferred that the appropriate concentration of nitrite was conducive to the rapid enrichment of DPAOs under alternative anaerobic/anoxic operation. Meanwhile, anaerobic/oxic condition was favorable for the enrichment of Candidatus Accumulibacter-related phosphorus removal organisms, and short-time post-aeration in the proposed method could reduce the potential public health hazard.
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Affiliation(s)
- Hongliang Dai
- a School of Energy and Environment , Southeast University , Nanjing , China
- b ERC Taihu Lake Water Environment (Wuxi) , Wuxi , China
| | - Xiwu Lu
- a School of Energy and Environment , Southeast University , Nanjing , China
- b ERC Taihu Lake Water Environment (Wuxi) , Wuxi , China
| | - Lihong Peng
- a School of Energy and Environment , Southeast University , Nanjing , China
- b ERC Taihu Lake Water Environment (Wuxi) , Wuxi , China
| | - Xiang Li
- a School of Energy and Environment , Southeast University , Nanjing , China
- b ERC Taihu Lake Water Environment (Wuxi) , Wuxi , China
| | - Zheqin Dai
- a School of Energy and Environment , Southeast University , Nanjing , China
- b ERC Taihu Lake Water Environment (Wuxi) , Wuxi , China
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26
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Dai H, Wu Y, Peng L, Dai Z, Li X, Lu X. Effects of calcium on the performance, bacterial population and microbial metabolism of a denitrifying phosphorus removal system. BIORESOURCE TECHNOLOGY 2017; 243:828-835. [PMID: 28724254 DOI: 10.1016/j.biortech.2017.07.039] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 07/01/2017] [Accepted: 07/06/2017] [Indexed: 06/07/2023]
Abstract
A sequencing batch reactor was operated to study the effects of influent Ca2+ on the efficiency, bacterial population, and microbial metabolism of denitrifying phosphorus removal system. Results showed that high Ca2+ loading (≥80mg/L) significantly inhibited the performance of simultaneous nitrogen and phosphorus removal. The abundance of phosphorus removal-related organisms (Dechloromonas and Candidatus Accumulibacter) decreased with increasing Ca2+ concentration from 20 to 140mg/L, while the abundance of glycogen-accumulating organisms and other bacteria increased. Metabolomic analyses revealed that the metabolic profiles of microbial community were also affected by high influent Ca2+ concentrations. 3-Hydroxybutyrate, acetate, alanine, and glutamate were the main differentiated metabolites in the system. An accumulation of amino acids and a reduction of nucleotides and amines were important response to high Ca2+ loading. Long-term Ca2+ loading had a reversible effect on the denitrifying phosphorus removal system as it could revive after a 50-day recovery process.
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Affiliation(s)
- Hongliang Dai
- School of Energy and Environment, Southeast University, No. 2 Sipailou Road, Nanjing 210096, China; ERC Taihu Lake Water Environment (Wuxi), No. 99 Linghu Road, Wuxi 214135, China
| | - Yifeng Wu
- School of Energy and Environment, Southeast University, No. 2 Sipailou Road, Nanjing 210096, China; ERC Taihu Lake Water Environment (Wuxi), No. 99 Linghu Road, Wuxi 214135, China
| | - Lihong Peng
- School of Energy and Environment, Southeast University, No. 2 Sipailou Road, Nanjing 210096, China; ERC Taihu Lake Water Environment (Wuxi), No. 99 Linghu Road, Wuxi 214135, China
| | - Zheqin Dai
- School of Energy and Environment, Southeast University, No. 2 Sipailou Road, Nanjing 210096, China; ERC Taihu Lake Water Environment (Wuxi), No. 99 Linghu Road, Wuxi 214135, China
| | - Xiang Li
- School of Energy and Environment, Southeast University, No. 2 Sipailou Road, Nanjing 210096, China; ERC Taihu Lake Water Environment (Wuxi), No. 99 Linghu Road, Wuxi 214135, China
| | - Xiwu Lu
- School of Energy and Environment, Southeast University, No. 2 Sipailou Road, Nanjing 210096, China; ERC Taihu Lake Water Environment (Wuxi), No. 99 Linghu Road, Wuxi 214135, China.
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Novel MBR_based main stream biological nutrient removal process: high performance and microbial community. Biodegradation 2017; 29:11-22. [PMID: 29080942 DOI: 10.1007/s10532-017-9810-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 10/23/2017] [Indexed: 10/18/2022]
Abstract
For municipal wastewater treatment, main stream biological nutrient removal (BNR) process is becoming more and more important. This lab-scale study, novel MBR_based BNR processes (named A2N-MBR and A2NO-MBR) were built. Comparison of the COD removal, results obtained demonstrated that COD removal efficiencies were almost the same in three processes, with effluent concentration all bellowed 30 mg L-1. However, the two-sludge systems (A2N-MBR and A2NO-MBR) had an obvious advantage over the A2/O for denitrification and phosphorus removal, with the average TP removal rates of 91.20, 98.05% and TN removal rates of 73.00, 79.49%, respectively, higher than that of 86.45 and 61.60% in A2/O process. Illumina Miseq sequencing revealed that Candidatus_Accumulibacter, which is capable of using nitrate as an electron acceptor for phosphorus and nitrogen removal simultaneously, was the dominant phylum in both A2N-MBR and A2NO-MBR process, accounting for 28.74 and 23.98%, respectively. Distinguishingly, major organism groups related to nitrogen and phosphorus removal in A2/O system were Anaerolineaceae_uncultured, Saprospiraceae_uncultured and Thauera, with proportions of 11.31, 8.56 and 5.00%, respectively. Hence, the diversity of dominant PAOs group was likely responsible for the difference in nitrogen and phosphorus removal in the three processes.
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28
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Terashima M, Yama A, Sato M, Yumoto I, Kamagata Y, Kato S. Culture-Dependent and -Independent Identification of Polyphosphate-Accumulating Dechloromonas spp. Predominating in a Full-Scale Oxidation Ditch Wastewater Treatment Plant. Microbes Environ 2016; 31:449-455. [PMID: 27867159 PMCID: PMC5158118 DOI: 10.1264/jsme2.me16097] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
The oxidation ditch process is one of the most economical approaches currently used to simultaneously remove organic carbon, nitrogen, and also phosphorus (P) from wastewater. However, limited information is available on biological P removal in this process. In the present study, microorganisms contributing to P removal in a full-scale oxidation ditch reactor were investigated using culture-dependent and -independent approaches. A microbial community analysis based on 16S rRNA gene sequencing revealed that a phylotype closely related to Dechloromonas spp. in the family Rhodocyclaceae dominated in the oxidation ditch reactor. This dominant Dechloromonas sp. was successfully isolated and subjected to fluorescent staining for polyphosphate, followed by microscopic observations and a spectrofluorometric analysis, which clearly demonstrated that the Dechloromonas isolate exhibited a strong ability to accumulate polyphosphate within its cells. These results indicate the potential key role of Dechloromonas spp. in efficient P removal in the oxidation ditch wastewater treatment process.
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Affiliation(s)
- Mia Terashima
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST)
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29
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Saad SA, Welles L, Abbas B, Lopez-Vazquez CM, van Loosdrecht MCM, Brdjanovic D. Denitrification of nitrate and nitrite by 'Candidatus Accumulibacter phosphatis' clade IC. WATER RESEARCH 2016; 105:97-109. [PMID: 27603967 DOI: 10.1016/j.watres.2016.08.061] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Revised: 08/17/2016] [Accepted: 08/29/2016] [Indexed: 06/06/2023]
Abstract
Phosphate accumulating organisms (PAO) are assumed to use nitrate as external electron acceptor, allowing an efficient integration of simultaneous nitrogen and phosphate removal with minimal organic carbon (COD) requirements. However, contradicting findings appear in literature regarding the denitrification capacities of PAO due to the lack of clade specific highly enriched PAO cultures. Whereas some studies suggest that only PAO clade I may be capable of using nitrate as external electron acceptor for anoxic P-uptake, other studies indicate that PAO clade II may be responsible for anoxic P-removal. In the present study, a highly enriched PAO clade IC culture (>99% according to FISH) was cultivated in an SBR operated under Anaerobic/Oxic conditions and subsequently exposed to Anaerobic/Anoxic/Oxic conditions using nitrate as electron acceptor. Before and after acclimatization to the presence of nitrate, the aerobic and anoxic (nitrate and nitrite) activities of the PAO I culture were assessed through the execution of batch tests using either acetate or propionate as electron donor. In the presence of nitrate, significant P-uptake by PAO I was not observed before or after acclimatization. Using nitrite as electron acceptor, limited nitrite removal rates were observed before acclimatization with lower rates in the acetate fed reactor without P-uptake and slightly higher in the propionate fed reactor with a marginal anoxic P-uptake. Only after acclimatization to nitrate, simultaneous P and nitrite removal was observed. This study suggests that PAO clade IC is not capable of using nitrate as external electron acceptor for anoxic P-removal. The elucidation of the metabolic capacities for individual PAO clades helps in better understanding and optimization of the relation between microbial ecology and process performance in enhanced biological phosphate removal processes.
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Affiliation(s)
- Sondos A Saad
- Department of Civil Engineering, Faculty of Engineering, Ain Shams University, 1 El Sarayat St., Abbassia, 11517 Cairo, Egypt; Department of Environmental Engineering and Water Technology, UNESCO-IHE Institute for Water Education, Westvest 7, 2611 AX Delft, The Netherlands.
| | - Laurens Welles
- Department of Environmental Engineering and Water Technology, UNESCO-IHE Institute for Water Education, Westvest 7, 2611 AX Delft, The Netherlands; Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands.
| | - Ben Abbas
- Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands.
| | - Carlos M Lopez-Vazquez
- Department of Environmental Engineering and Water Technology, UNESCO-IHE Institute for Water Education, Westvest 7, 2611 AX Delft, The Netherlands.
| | - Mark C M van Loosdrecht
- Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands.
| | - Damir Brdjanovic
- Department of Environmental Engineering and Water Technology, UNESCO-IHE Institute for Water Education, Westvest 7, 2611 AX Delft, The Netherlands; Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, The Netherlands.
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Podedworna J, Zubrowska-Sudol M, Sytek-Szmeichel K, Gnida A, Surmacz-Górska J, Marciocha D. Impact of multiple wastewater feedings on the efficiency of nutrient removal in an IFAS-MBSBBR: number of feedings vs. efficiency of nutrient removal. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2016; 74:1457-1468. [PMID: 27685975 DOI: 10.2166/wst.2016.331] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
This article presents the results of research into the influence of one, two and three wastewater feedings in a cycle on efficiency and performance of combined biological nitrogen and phosphorus removal in an integrated fixed-film activated sludge and moving-bed sequencing batch biofilm reactor (IFAS-MBSBBR). The experiment lasted 158 days and was conducted in two laboratory models of the IFAS-MBSBBR with an active volume of 28 L. It was found that along with an increase in the number of wastewater feedings, an increase in nitrogen removal efficiency was observed (from 56.9 ± 2.30% for a single feeding to 91.4 ± 1.77% for three feedings). Moreover, the contribution of simultaneous nitrification/denitrification in nitrogen removal increased (from 2.58% for a single feeding to 69.5% for three feedings). Systems with a greater number of feedings stimulated the process of denitrifying phosphorus removal. Regardless of the way in which wastewater feeding was applied to the IFAS-MBSBBR, highly efficient chemical oxygen demand (COD) removal (94.8 ± 1.80%) and biological phosphorus removal (98.9 ± 0.87%) were achieved.
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Affiliation(s)
- J Podedworna
- Faculty of Building Services, Hydro and Environmental Engineering, Warsaw University of Technology, Nowowiejska Str. 20, Warsaw 00-653, Poland E-mail:
| | - M Zubrowska-Sudol
- Faculty of Building Services, Hydro and Environmental Engineering, Warsaw University of Technology, Nowowiejska Str. 20, Warsaw 00-653, Poland E-mail:
| | - K Sytek-Szmeichel
- Faculty of Building Services, Hydro and Environmental Engineering, Warsaw University of Technology, Nowowiejska Str. 20, Warsaw 00-653, Poland E-mail:
| | - A Gnida
- Faculty of Energy and Environmental Engineering, Environmental Biotechnology Department, Silesian University of Technology, Krzywoustego Str. 8, Gliwice 44-100, Poland
| | - J Surmacz-Górska
- Faculty of Energy and Environmental Engineering, Environmental Biotechnology Department, Silesian University of Technology, Akademicka Str. 2, Gliwice 44-100, Poland
| | - D Marciocha
- Faculty of Energy and Environmental Engineering, Environmental Biotechnology Department, Silesian University of Technology, Krzywoustego Str. 8, Gliwice 44-100, Poland
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Zou H, Wang Y. Phosphorus removal and recovery from domestic wastewater in a novel process of enhanced biological phosphorus removal coupled with crystallization. BIORESOURCE TECHNOLOGY 2016; 211:87-92. [PMID: 27003794 DOI: 10.1016/j.biortech.2016.03.073] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Revised: 03/10/2016] [Accepted: 03/13/2016] [Indexed: 06/05/2023]
Abstract
A new process of enhanced biological phosphorus removal coupled with crystallization recovery of phosphorus was developed here, where the feasibility of nutrients removal and potential for phosphorus recovery from domestic wastewater was further assessed. Results showed that an excellent nutrients removal and phosphorus recovery performance was achieved, in which the averaged COD, PO4(3-)-P and NO3(-)-N removal efficiencies were 82.6%, 87.5% and 91.6%, respectively and a total of 59.3% of phosphorus was recovered as hydroxyapatite. What's more, crystallization recovery of phosphorus greatly enhanced the biological phosphorus removal efficiency. After the incorporation of the phosphorus recovery column via side-stream, the phosphorus concentration of effluent was significantly decreased ranging from 1.24mg/L to 0.85mg/L, 0.52mg/L and 0.41mg/L at the lateral flow ratios of 0, 0.1, 0.2 and 0.3, respectively. The results obtained here would be beneficial to provide a prospective alternative for phosphorus removal and recovery from wastewater.
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Affiliation(s)
- Haiming Zou
- Department of Resource and Environment, Anhui Science and Technology University, Donghua Road, Fengyang 233100, China; Key Laboratory of Bioorganic Fertilizer Creation, Ministry of Agriculture, Bengbu 234000, China.
| | - Yan Wang
- Department of Resource and Environment, Anhui Science and Technology University, Donghua Road, Fengyang 233100, China; Key Laboratory of Bioorganic Fertilizer Creation, Ministry of Agriculture, Bengbu 234000, China
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32
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Anoxic–aerobic SBR system for nitrate, phosphate and COD removal from high-strength wastewater and diversity study of microbial communities. Biochem Eng J 2016. [DOI: 10.1016/j.bej.2015.09.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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33
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Gangl D, Zedler JAZ, Rajakumar PD, Martinez EMR, Riseley A, Włodarczyk A, Purton S, Sakuragi Y, Howe CJ, Jensen PE, Robinson C. Biotechnological exploitation of microalgae. JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:6975-90. [PMID: 26400987 DOI: 10.1093/jxb/erv426] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Microalgae are a diverse group of single-cell photosynthetic organisms that include cyanobacteria and a wide range of eukaryotic algae. A number of microalgae contain high-value compounds such as oils, colorants, and polysaccharides, which are used by the food additive, oil, and cosmetic industries, among others. They offer the potential for rapid growth under photoautotrophic conditions, and they can grow in a wide range of habitats. More recently, the development of genetic tools means that a number of species can be transformed and hence used as cell factories for the production of high-value chemicals or recombinant proteins. In this article, we review exploitation use of microalgae with a special emphasis on genetic engineering approaches to develop cell factories, and the use of synthetic ecology approaches to maximize productivity. We discuss the success stories in these areas, the hurdles that need to be overcome, and the potential for expanding the industry in general.
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Affiliation(s)
- Doris Gangl
- Centre for Molecular Processing, School of Biosciences, University of Kent, Canterbury CT2 7NJ, UK
| | - Julie A Z Zedler
- Centre for Molecular Processing, School of Biosciences, University of Kent, Canterbury CT2 7NJ, UK
| | - Priscilla D Rajakumar
- Institute of Structural & Molecular Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Erick M Ramos Martinez
- Copenhagen Plant Science Centre, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark
| | - Anthony Riseley
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK
| | - Artur Włodarczyk
- Copenhagen Plant Science Centre, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark
| | - Saul Purton
- Institute of Structural & Molecular Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Yumiko Sakuragi
- Copenhagen Plant Science Centre, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark
| | - Christopher J Howe
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK
| | - Poul Erik Jensen
- Copenhagen Plant Science Centre, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark
| | - Colin Robinson
- Centre for Molecular Processing, School of Biosciences, University of Kent, Canterbury CT2 7NJ, UK
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Simultaneous effective carbon and nitrogen removals and phosphorus recovery in an intermittently aerated membrane bioreactor integrated system. Sci Rep 2015; 5:16281. [PMID: 26541793 PMCID: PMC4635345 DOI: 10.1038/srep16281] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 10/13/2015] [Indexed: 11/08/2022] Open
Abstract
Recovering nutrients, especially phosphate resource, from wastewater have attracted increasing interest recently. Herein, an intermittently aerated membrane bioreactor (MBR) with a mesh filter was developed for simultaneous chemical oxygen demand (COD), total nitrogen (TN) and phosphorous removal, followed by phosphorus recovery from the phosphorus-rich sludge. This integrated system showed enhanced performances in nitrification and denitrification and phosphorous removal without excess sludge discharged. The removal of COD, TN and total phosphorus (TP) in a modified MBR were averaged at 94.4 ± 2.5%, 94.2 ± 5.7% and 53.3 ± 29.7%, respectively. The removed TP was stored in biomass, and 68.7% of the stored phosphorous in the sludge could be recovered as concentrated phosphate solution with a concentration of phosphate above 350 mg/L. The sludge after phosphorus release could be returned back to the MBR for phosphorus uptake, and 83.8% of its capacity could be recovered.
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Denitrifying capability and community dynamics of glycogen accumulating organisms during sludge granulation in an anaerobic-aerobic sequencing batch reactor. Sci Rep 2015; 5:12904. [PMID: 26257096 PMCID: PMC4530441 DOI: 10.1038/srep12904] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Accepted: 06/12/2015] [Indexed: 11/24/2022] Open
Abstract
Denitrifying capability of glycogen accumulating organisms (GAOs) has received great attention in environmental science and microbial ecology. Combining this ability with granule processes would be an interesting attempt. Here, a laboratory-scale sequencing batch reactor (SBR) was operated to enrich GAOs and enable sludge granulation. The results showed that the GAO granules were cultivated successfully and the granules had denitrifying capability. The batch experiments demonstrated that all NO3−-N could be removed or reduced, some amount of NO2−-N were accumulated in the reactor, and N2 was the main gaseous product. SEM analysis suggested that the granules were tightly packed with a large amount of tetrad-forming organisms (TFOs); filamentous bacteria served as the supporting structures for the granules. The microbial community structure of GAO granules was differed substantially from the inoculant conventional activated sludge. Most of the bacteria in the seed sludge grouped with members of Proteobacterium. FISH analysis confirmed that GAOs were the predominant members in the granules and were distributed evenly throughout the granular space. In contrast, PAOs were severely inhibited. Overall, cultivation of the GAO granules and utilizing their denitrifying capability can provide us with a new approach of nitrogen removal and saving more energy.
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Liu Y, Peng L, Chen X, Ni BJ. Mathematical Modeling of Nitrous Oxide Production during Denitrifying Phosphorus Removal Process. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:8595-8601. [PMID: 26114730 DOI: 10.1021/acs.est.5b01650] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A denitrifying phosphorus removal process undergoes frequent alternating anaerobic/anoxic conditions to achieve phosphate release and uptake, during which microbial internal storage polymers (e.g., Polyhydroxyalkanoate (PHA)) could be produced and consumed dynamically. The PHA turnovers play important roles in nitrous oxide (N2O) accumulation during the denitrifying phosphorus removal process. In this work, a mathematical model is developed to describe N2O dynamics and the key role of PHA consumption on N2O accumulation during the denitrifying phosphorus removal process for the first time. In this model, the four-step anoxic storage of polyphosphate and four-step anoxic growth on PHA using nitrate, nitrite, nitric oxide (NO), and N2O consecutively by denitrifying polyphosphate accumulating organisms (DPAOs) are taken into account for describing all potential N2O accumulation steps in the denitrifying phosphorus removal process. The developed model is successfully applied to reproduce experimental data on N2O production obtained from four independent denitrifying phosphorus removal study reports with different experimental conditions. The model satisfactorily describes the N2O accumulation, nitrogen reduction, phosphate release and uptake, and PHA dynamics for all systems, suggesting the validity and applicability of the model. The results indicated a substantial role of PHA consumption in N2O accumulation due to the relatively low N2O reduction rate by using PHA during denitrifying phosphorus removal.
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Affiliation(s)
- Yiwen Liu
- Advanced Water Management Centre, The University of Queensland, St. Lucia, Brisbane, QLD 4072, Australia
| | - Lai Peng
- Advanced Water Management Centre, The University of Queensland, St. Lucia, Brisbane, QLD 4072, Australia
| | - Xueming Chen
- Advanced Water Management Centre, The University of Queensland, St. Lucia, Brisbane, QLD 4072, Australia
| | - Bing-Jie Ni
- Advanced Water Management Centre, The University of Queensland, St. Lucia, Brisbane, QLD 4072, Australia
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Begum SA, Batista JR. Impact of butyrate on microbial selection in enhanced biological phosphorus removal systems. ENVIRONMENTAL TECHNOLOGY 2014; 35:2961-2972. [PMID: 25189844 DOI: 10.1080/09593330.2014.927531] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Microbial selection in an enhanced biological phosphorus removal system was investigated in a laboratory-scale sequencing batch reactor fed exclusively with butyrate as a carbon source. As reported in the few previous studies, butyrate uptake was slow and phosphorus (P) release occurred during the entire anaerobic period. Polyphosphate-accumulating organism (PAO), i.e. Candidatus Accumulibacter phosphatis (named as Accumulibacter), glycogen-accumulating organisms (GAOs), i.e. Candidatus Competibacter phosphatis (named as Competibacter) and Defluviicoccus-related, tetrad-forming alphaproteobacteria (named as Defluviicoccus) were identified using fluorescence in situ hybridization analysis. The results show that Accumulibacter and Defluviicoccus were selected in the butyrate-fed reactor, whereas Competibacter was not selected. P removal was efficient at the beginning of the experiment with an increasing percentage relative abundance (% RA) of PAOs. The % RA of Accumulibacter and Defluviicoccus increased from 13% to 50% and 8% to 16%, respectively, and the % RA of Competibacter decreased from 8% to 2% during the experiment. After 6 weeks, P removal deteriorated with the poor correlation between the percentage of P removal and % RA of GAOs.
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Affiliation(s)
- Shamim A Begum
- a Department of Chemical Engineering , Tuskegee University , 522E Luther Foster Hall, Tuskegee , AL 36088 , USA
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Kagawa Y, Tahata J, Kishida N, Matsumoto S, Picioreanu C, van Loosdrecht M, Tsuneda S. Modeling the nutrient removal process in aerobic granular sludge system by coupling the reactor- and granule-scale models. Biotechnol Bioeng 2014; 112:53-64. [DOI: 10.1002/bit.25331] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Revised: 06/21/2014] [Accepted: 07/03/2014] [Indexed: 11/09/2022]
Affiliation(s)
- Y. Kagawa
- Institute for Nanoscience and Nanotechnology; Waseda University; Tokyo Japan
| | - J. Tahata
- Department of Life Science and Medical Bioscience; Waseda University; 2-2 Wakamatsu-cho Shinjuku-ku Tokyo 162-8480 Japan
| | - N. Kishida
- Department of Civil and Environmental Engineering; Waseda University; Tokyo Japan
| | - S. Matsumoto
- Department of Life Science and Medical Bioscience; Waseda University; 2-2 Wakamatsu-cho Shinjuku-ku Tokyo 162-8480 Japan
| | - C. Picioreanu
- Department of Biotechnology; Delft University of Technology; Delft The Netherlands
| | | | - S. Tsuneda
- Institute for Nanoscience and Nanotechnology; Waseda University; Tokyo Japan
- Department of Life Science and Medical Bioscience; Waseda University; 2-2 Wakamatsu-cho Shinjuku-ku Tokyo 162-8480 Japan
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Operation performance and microbial community dynamics of phosphorus removal sludge with different electron acceptors. ACTA ACUST UNITED AC 2014; 41:1099-108. [DOI: 10.1007/s10295-014-1444-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Accepted: 04/02/2014] [Indexed: 10/25/2022]
Abstract
Abstract
Operation performances of phosphorus removal sludge with different electron acceptors in three parallel SBRs were firstly compared in the present study, and the effect of post-aeration on denitrifying phosphorus removal was also studied. Moreover, community dynamics of different phosphorus removal sludge was systematically investigated with high-throughput sequencing for the first time. TP removal rates for nitrate-, nitrite-, and oxygen-based phosphorus removal sludge were 84.8, 78.5, and 87.4 %, with an average effluent TP concentration of 0.758, 0.931, and 0.632 mg/l. The average specific phosphorus release and uptake rates were 20.3, 10.8, and 21.5, and 9.43, 8.68, and 10.8 mgP/(gVSS h), respectively. Moreover, electron utilization efficiency of denitrifying phosphorus removal sludge with nitrate as electron acceptor was higher than nitrite, with P/e− were 2.21 and 1.51 mol-P/mol-e−, respectively. With the assistance of post-aeration for nitrate-based denitrifying phosphorus removal sludge, settling ability could be improved, with SVI decreased from 120 to 80 and 72 ml/g when post-aeration time was 0, 10, and 30 min, respectively. Moreover, further phosphorus removal could be achieved during post-aeration with increased aeration time. However, the anoxic phosphorus uptake was deteriorated, which was likely a result of shifted microbial community structure. Post-aeration of approximately 10 min was proposed for denitrifying phosphorus removal. Nitrate- and nitrite-based denitrifying phosphorus removal sludge exhibited similar community structure. More phosphorus accumulating organisms were enriched under anaerobic–aerobic conditions, while anaerobic–anoxic conditions were favorable for suppressing glycogen-accumulating organisms. Significant differences in pathogenic bacterial community profiles revealed in the current study indicated the potential public health hazards of non-aeration activated sludge system.
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Lv XM, Shao MF, Li CL, Li J, Gao XL, Sun FY. A comparative study of the bacterial community in denitrifying and traditional enhanced biological phosphorus removal processes. Microbes Environ 2014; 29:261-8. [PMID: 24964811 PMCID: PMC4159037 DOI: 10.1264/jsme2.me13132] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Denitrifying phosphorus removal is an attractive wastewater treatment process due to its reduced carbon source demand and sludge minimization potential. Two lab-scale sequencing batch reactors (SBRs) were operated in alternating anaerobic-anoxic (A-A) or anaerobic-oxic (A-O) conditions to achieve denitrifying enhanced biological phosphate removal (EBPR) and traditional EBPR. No significant differences were observed in phosphorus removal efficiencies between A-A SBR and A-O SBR, with phosphorus removal rates being 87.9% and 89.0% respectively. The community structures in denitrifying and traditional EBPR processes were evaluated by high-throughput sequencing of the PCR-amplified partial 16S rRNA genes from each sludge. The results obtained showed that the bacterial community was more diverse in A-O sludge than in A-A sludge. Taxonomy and β-diversity analyses indicated that a significant shift occurred in the dominant microbial community in A-A sludge compared with the seed sludge during the whole acclimation phase, while a slight fluctuation was observed in the abundance of the major taxonomies in A-O sludge. One Dechloromonas-related OTU outside the 4 known Candidatus “Accumulibacter” clades was detected as the main OTU in A-A sludge at the stationary operation, while Candidatus “Accumulibacter” dominated in A-O sludge.
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Affiliation(s)
- Xiao-Mei Lv
- Harbin Institute of Technology Shenzhen Graduate School
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Chen J, Tang YQ, Li Y, Nie Y, Hou L, Li XQ, Wu XL. Impacts of different nanoparticles on functional bacterial community in activated sludge. CHEMOSPHERE 2014; 104:141-148. [PMID: 24280055 DOI: 10.1016/j.chemosphere.2013.10.082] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 10/22/2013] [Accepted: 10/30/2013] [Indexed: 06/02/2023]
Abstract
Rapidly developing industry raises concerns about the environmental impacts of nanoparticles, but the effects of inorganic nanoparticles on functional bacterial community in wastewater treatment remain unclear. The discriminated effects of silver nanoparticles (Ag-NP) and zinc oxide nanoparticles (ZnO-NP) in a simulated sequencing batch reactor (SBR) system were therefore evaluated by the RNA-based terminal restricted fragment length polymorphism (T-RFLP), 16S rcDNA gene clone library and real-time reverse transcription-PCR (RT-PCR) analyses. Although the COD and NH4-N removal efficiencies were not or slightly reduced by the addition of ZnO-NP and Ag-NP, the functional bacterial community changed remarkably. The denitrification related species were inhibited by high dosage of ZnO-NP and Ag-NP, including Diaphorobacter species, Thauera species and those in the Sphaerotilus-Leptothrix group. However, the bacteria related to sludge bulking, heavy metal resistant and biosorption were increased, especially by ZnO-NPs treatment, including those closely related to Haliscomenobacter hydrossis, Zoogloea ramigera and Methyloversatilis universalis. In addition, Ag-NP and ZnO-NP treatments influenced the functional bacterial community differently. Increasing of bulking related bacteria may help to compensate the COD removal efficiency and to maintain functional redundancy, but could lead to operation failure of activated sludge system when expose to ZnO-NPs.
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Affiliation(s)
- Jian Chen
- College of Engineering, Peking University, Beijing 100871, PR China
| | - Yue-Qin Tang
- College of Architecture and Environment, Sichuan University, Chengdu 610065, PR China
| | - Yan Li
- College of Engineering, Peking University, Beijing 100871, PR China
| | - Yong Nie
- College of Engineering, Peking University, Beijing 100871, PR China
| | - Linlin Hou
- Laboratory of Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, PR China
| | - Xi-Qing Li
- Laboratory of Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, PR China.
| | - Xiao-Lei Wu
- College of Engineering, Peking University, Beijing 100871, PR China.
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Miao Z, Zeng W, Wang S, Peng Y, Cao G, Weng D, Xue G, Yang Q. Effect of temperature on anoxic metabolism of nitrites to nitrous oxide by polyphosphate accumulating organisms. J Environ Sci (China) 2014; 26:264-273. [PMID: 25076517 DOI: 10.1016/s1001-0742(13)60406-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Temperature is an important physical factor, which strongly influences biomass and metabolic activity. In this study, the effects of temperature on the anoxic metabolism of nitrite (NO2(-)) to nitrous oxide (N2O) by polyphosphate accumulating organisms, and the process of the accumulation of N2O (during nitrite reduction), which acts as an electron acceptor, were investigated using 91% +/- 4% Candidatus Accumulibacter phosphatis sludge. The results showed that N2O is accumulated when Accumulibacter first utilize nitrite instead of oxygen as the sole electron acceptor during the denitrifying phosphorus removal process. Properties such as nitrite reduction rate, phosphorus uptake rate, N2O reduction rate, and polyhydroxyalkanoate degradation rate were all influenced by temperature variation (over the range from 10 to 30 degrees C reaching maximum values at 25 degrees C). The reduction rate of N2O by N2O reductase was more sensitive to temperature when N2O was utilized as the sole electron acceptor instead of N2O, and the N2O reduction rates, ranging from 0.48 to 3.53 N20-N/(hr x g VSS), increased to 1.45 to 8.60 mg N2O-N/(hr x g VSS). The kinetics processes for temperature variation of 10 to 30 degrees C were (theta1 = 1.140-1.216 and theta2 = 1.139-1.167). In the range of 10 degrees C to 30 degrees C, almost all of the anoxic stoichiometry was sensitive to temperature changes. In addition, a rise in N2O reduction activity leading to a decrease in N2O accumulation in long term operations at the optimal temperature (27 degrees C calculated by the Arrhenius model).
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Krasnits E, Beliavski M, Tarre S, Green M. The contribution of suspended solids to municipal wastewater PHA-based denitrification. ENVIRONMENTAL TECHNOLOGY 2014; 35:313-321. [PMID: 24600870 DOI: 10.1080/09593330.2013.827728] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The role of wastewater suspended solids in denitrification based on intracellular carbon storage was investigated in a biofilm sequencing batch reactor performing alternately anaerobic carbon storage and denitrification. Municipal wastewater as the feeding was compared with filtered wastewater and with acetate. The results show that the amount of PHA (polyhydroxyalkanoates) stored during a cycle was quite similar, irrespective of the substrate type used as feeding (acetate, real wastewater and real wastewater after filtration). PHA storage was limited even under excess chemical oxygen demand (COD) conditions, with a reducing power capacity enough for denitrification of only 25-26 mg/L N. However, when non-filtered wastewater was used, the denitrification capacity was about 50% higher (38 mg/L N) due to the contribution of entrapped suspended solids as the electron donor. In addition, the involvement of the hydrolyzed wastewater suspended solids resulted in a different PHA composition containing a much higher poly-3-hydroxyvalerate content.
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Wong PY, Cheng KY, Kaksonen AH, Sutton DC, Ginige MP. A novel post denitrification configuration for phosphorus recovery using polyphosphate accumulating organisms. WATER RESEARCH 2013; 47:6488-6495. [PMID: 24041527 DOI: 10.1016/j.watres.2013.08.023] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Revised: 07/23/2013] [Accepted: 08/17/2013] [Indexed: 06/02/2023]
Abstract
Enhanced biological phosphorus removal (EBPR) has been widely used to remove phosphorus (P) from wastewater. In this study we report a novel modification to the EBPR approach, namely enhanced biological phosphorus removal and recovery (EBPR-r) that facilitates biological recovery of P from wastewater using a post denitrification configuration. The novel approach consists of two major steps. In the first step, a biofilm of phosphorus accumulating organisms (PAOs) is exposed to a wastewater stream in the absence of active aeration, during which P is taken up by the biofilm using nitrate and residual dissolved oxygen as electron acceptors. Thus, P and nitrogen (N) removal from wastewater is achieved. During the second step, the P enriched biofilm is exposed to a smaller recovery stream supplemented with an external carbon source to facilitate P release under anaerobic conditions. This allows P to be recovered as a concentrated liquid. The EBPR-r process was able to generate a P recovery stream four time more concentrated (28 mg-P/L) than the wastewater stream (7 mg-P/L), while removing nitrate (denitrification) from the wastewater stream. Repeated exposure of the biofilm (10 P-uptake and release cycles) to a recovery stream yielded up to 100 mg-P/L. Overall, EBPR-r is the first post denitrification strategy that can also facilitate P recovery during secondary wastewater treatment.
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Affiliation(s)
- Pan Yu Wong
- CSIRO Land and Water, Private Bag No. 5, Wembley, WA 6913, Australia; School of Pathology and Laboratory Medicine, University of Western Australia, Nedlands, WA 6009, Australia
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Tian WD, Lopez-Vazquez CM, Li WG, Brdjanovic D, van Loosdrecht MCM. Occurrence of PAOI in a low temperature EBPR system. CHEMOSPHERE 2013; 92:1314-1320. [PMID: 23732004 DOI: 10.1016/j.chemosphere.2013.05.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2012] [Revised: 05/07/2013] [Accepted: 05/08/2013] [Indexed: 06/02/2023]
Abstract
The occurrence of Accumulibacter Type I (a known phosphorus-accumulating organism, PAO) has received increased attention due to the potential operating benefits associated with their denitrifying activity in enhanced biological phosphorus removal (EBPR) wastewater treatment plants. In this study, after a shift from an enriched glycogen-accumulating organism (GAO) culture (competitors of PAO) to a PAO-enriched system, Accumulibacter Type I (PAO I) became dominant in an anaerobic-aerobic EBPR system fed with acetate and operated at 10°C with a net aerobic solids retention time (SRT) of 6 d. Since Accumulibacter Type II (PAO II) were not detected, the low temperature in combination with the net aerobic SRT applied appeared to have suppressed their growth as well. The stoichiometry of PAO I was in agreement with previous metabolic models, suggesting that it was the main PAO organisms present in previous studies operated under similar conditions. Moreover, under poly-P limiting conditions, PAO I were unable to switch to a GAO-like metabolism at low temperatures. These results contribute to increase the understanding of the physiology, microbial metabolism and microbial ecology of PAO I.
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Affiliation(s)
- Wen-De Tian
- Department of Biotechnology, Delft University of Technology, Delft, The Netherlands
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Li C, Zhang J, Liang S, Ngo HH, Guo W, Zhang Y, Zou Y. Nitrous oxide generation in denitrifying phosphorus removal process: main causes and control measures. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2013; 20:5353-5360. [PMID: 23407928 DOI: 10.1007/s11356-013-1530-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Accepted: 01/28/2013] [Indexed: 06/01/2023]
Abstract
Despite the many benefits of denitrifying phosphorus removal process, the significant generation of nitrous oxide (N2O), a potent greenhouse gas, remains a problem for this innovative and promising process. To better understand and more effectively control N2O generation in denitrifying phosphorus removal process, batch experiments were carried out to investigate the main causes of N2O generation, based on which the control measures were subsequently proposed. The results showed that N2O generation accounted for 0.41 % of the total nitrogen removal in denitrifying phosphorus removal process, whereas, in contrast, almost no N2O was generated in conventional denitrification process. It was further demonstrated that the weak competition of N2O reductase for electrons and the high nitrite accumulation were the two main causes for N2O generation, evidenced by N2O production and reduction rates under different conditions. Accordingly, the reduction of N2O generation was successfully achieved via two control measures: (1) the use of continuous nitrate addition reducing N2O generation by around 91.4 % and (2) the use of propionate as the carbon source reducing N2O generation by around 69.8 %.
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Affiliation(s)
- Cong Li
- Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan, 250100, Shandong, China
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Impact of nitrite on aerobic phosphorus uptake by poly-phosphate accumulating organisms in enhanced biological phosphorus removal sludges. Bioprocess Biosyst Eng 2013; 37:277-87. [DOI: 10.1007/s00449-013-0993-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Accepted: 06/05/2013] [Indexed: 10/26/2022]
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Krasnits E, Beliavsky M, Tarre S, Green M. PHA based denitrification: municipal wastewater vs. acetate. BIORESOURCE TECHNOLOGY 2013; 132:28-37. [PMID: 23395755 DOI: 10.1016/j.biortech.2012.11.074] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Revised: 11/11/2012] [Accepted: 11/19/2012] [Indexed: 06/01/2023]
Abstract
Denitrification of municipal wastewater based on bacterial storage polymers-Polyhydroxyalkanoates (PHA) - was investigated in biofilm sequencing batch reactors, as a part of a two sludge system for wastewater treatment and in comparison to acetate based synthetic wastewater. The results show that PHA based denitrification (PBD) of real wastewater can be a viable alternative, especially for wastewater with low COD/N ratio, without the need for external carbon source addition. High nitrate removal capacity of about 40-50 mg N/L with a low COD/N requirement of about 4-5, were observed. It was found that entrapped particulate organic matter contributed additional reducing power, on top of the storage materials, thus allowing for the high nitrate reduction capacity. Daily removal rates were similar to those of extensive treatment systems (0.24-0.31 gr N/L reactor*d). Large differences in storage yield and composition between biomass grown on synthetic and municipal wastewater were observed.
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Affiliation(s)
- Eli Krasnits
- Faculty of Civil and Environmental Engineering, Technion, Haifa 32000, Israel
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Characterization of the denitrification-associated phosphorus uptake properties of "Candidatus Accumulibacter phosphatis" clades in sludge subjected to enhanced biological phosphorus removal. Appl Environ Microbiol 2013; 79:1969-79. [PMID: 23335771 DOI: 10.1128/aem.03464-12] [Citation(s) in RCA: 100] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
To characterize the denitrifying phosphorus (P) uptake properties of "Candidatus Accumulibacter phosphatis," a sequencing batch reactor (SBR) was operated with acetate. The SBR operation was gradually acclimated from anaerobic-oxic (AO) to anaerobic-anoxic-oxic (A2O) conditions by stepwise increases of nitrate concentration and the anoxic time. The communities of "Ca. Accumulibacter" and associated bacteria at the initial (AO) and final (A2O) stages were compared using 16S rRNA and polyphosphate kinase genes and using fluorescence in situ hybridization (FISH). The acclimation process led to a clear shift in the relative abundances of recognized "Ca. Accumulibacter" subpopulations from clades IIA > IA > IIF to clades IIC > IA > IIF, as well as to increases in the abundance of other associated bacteria (Dechloromonas [from 1.2% to 19.2%] and "Candidatus Competibacter phosphatis" [from 16.4% to 20.0%]), while the overall "Ca. Accumulibacter" abundance decreased (from 55.1% to 29.2%). A series of batch experiments combined with FISH/microautoradiography (MAR) analyses was performed to characterize the denitrifying P uptake properties of the "Ca. Accumulibacter" clades. In FISH/MAR experiments using slightly diluted sludge (∼0.5 g/liter), all "Ca. Accumulibacter" clades successfully took up phosphorus in the presence of nitrate. However, the "Ca. Accumulibacter" clades showed no P uptake in the presence of nitrate when the sludge was highly diluted (∼0.005 g/liter); under these conditions, reduction of nitrate to nitrite did not occur, whereas P uptake by "Ca. Accumulibacter" clades occurred when nitrite was added. These results suggest that the "Ca. Accumulibacter" cells lack nitrate reduction capabilities and that P uptake by "Ca. Accumulibacter" is dependent upon nitrite generated by associated nitrate-reducing bacteria such as Dechloromonas and "Ca. Competibacter."
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