1
|
Huang ZS, Tan XQ, Yang HB, Zeng Y, Chen SJ, Wei ZS, Huang YQ. Mechanistic insights into tris(2-chloroisopropyl) phosphate biomineralization coupled with lead (II) biostabilization driven by denitrifying bacteria. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 945:173927. [PMID: 38901584 DOI: 10.1016/j.scitotenv.2024.173927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2024] [Revised: 05/24/2024] [Accepted: 06/09/2024] [Indexed: 06/22/2024]
Abstract
The ubiquity and persistence of organophosphate esters (OPEs) and heavy metal (HMs) pose global environmental risks. This study explored tris(2-chloroisopropyl)phosphate (TCPP) biomineralization coupled to lead (Pb2+) biostabilization driven by denitrifying bacteria (DNB). The domesticated DNB achieved synergistic bioremoval of TCPP and Pb2+ in the batch bioreactor (efficiency: 98 %).TCPP mineralized into PO43- and Cl-, and Pb2+ precipitated with PO43-. The TCPP-degrading/Pb2+-resistant DNB: Achromobacter, Pseudomonas, Citrobacter, and Stenotrophomonas, dominated the bacterial community, and synergized TCPP biomineralization and Pb2+ biostabilization. Metagenomics and metaproteomics revealed TCPP underwent dechlorination, hydrolysis, the TCA cycle-based dissimilation, and assimilation; Pb2+ was detoxified via bioprecipitation, bacterial membrane biosorption, EPS biocomplexation, and efflux out of cells. TCPP, as an initial donor, along with NO3-, as the terminal acceptor, formed a respiratory redox as the primary energy metabolism. Both TCPP and Pb2+ can stimulate phosphatase expression, which established the mutual enhancements between their bioconversions by catalyzing TCPP dephosphorylation and facilitating Pb2+ bioprecipitation. TCPP may alleviate the Pb2+-induced oxidative stress by aiding protein phosphorylation. 80 % of Pb2+ converted into crystalized pyromorphite. These results provide the mechanistic foundations and help develop greener strategies for synergistic bioremediation of OPEs and HMs.
Collapse
Affiliation(s)
- Zhen-Shan Huang
- School of Environment, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety, MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
| | - Xiu-Qin Tan
- State Environmental Protection Key Laboratory of Water Environmental Simulation and Pollution Control, South China Institute of Environmental Sciences, MEE, Guangzhou 510530, China
| | - Han-Biao Yang
- School of Environment, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety, MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
| | - Yuan Zeng
- School of Environment, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety, MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
| | - She-Jun Chen
- School of Environment, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety, MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China.
| | - Zai-Shan Wei
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Guangzhou 510275, China
| | - Yu-Qi Huang
- School of Environment, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety, MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
| |
Collapse
|
2
|
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.
Collapse
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.
| |
Collapse
|
3
|
Liang J, Zhang CM, Cao YX. Nutrient removal and microbial community succession in moving bed biofilm reactor: Effects of influent carbon to nitrogen ratio fluctuation. BIORESOURCE TECHNOLOGY 2024; 406:131008. [PMID: 38897547 DOI: 10.1016/j.biortech.2024.131008] [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: 03/26/2024] [Revised: 05/10/2024] [Accepted: 06/16/2024] [Indexed: 06/21/2024]
Abstract
This study investigated the nutrient removal and microbial community succession in moving bed biofilm reactor under stable and three levels of influent carbon/nitrogen (C/N) ratio fluctuation (± 10%, ± 20%, and ± 30%). Under the conditions of influent C/N ratio fluctuation, the removal efficiency of COD and PO43--P decreased 4.7-6.4% and 3.7-12.9%, respectively, while the nitrogen removal was almost unaffected. A sharp decrease in the content of culturable functional bacteria related to nitrogen and phosphorus removal including nitrite-oxidizing bacteria (NOB), aerobic denitrifying bacteria (DNB), and polyphosphate-accumulating organisms (PAOs) from the carrier biofilm was observed. Sequencing analysis revealed that the abundance of Candidatus Competibacter increased 10.3-25.9% and became the dominant genus responsible for denitrification, potentially indicating that nitrate was removed via endogenous denitrification under the influent C/N ratio fluctuation. The above results will provide basic data for the nutrient removal in decentralized wastewater treatment under highly variable influent conditions.
Collapse
Affiliation(s)
- Jie Liang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Key Laboratory of Northwest Water Resource, Environment and Ecology, Ministry of Education, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Chong-Miao Zhang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Key Laboratory of Northwest Water Resource, Environment and Ecology, Ministry of Education, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; International Science and Technology Cooperation Center for Urban Alternative Water Resources Development, Xi'an University of Architecture and Technology, Xi'an 710055, China.
| | - Yin-Xiang Cao
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Key Laboratory of Northwest Water Resource, Environment and Ecology, Ministry of Education, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| |
Collapse
|
4
|
Li G, Tooker NB, Wang D, Srinivasan V, Barnard JL, Russell A, Stinson B, McQuarrie J, Schauer P, Menniti A, Varga E, Hauduc H, Takács I, Bott C, Dobrowski P, Onnis-Hayden A, Gu AZ. Modeling versatile and dynamic anaerobic metabolism for PAOs/GAOs competition using agent-based model and verification via single cell Raman Micro-spectroscopy. WATER RESEARCH 2023; 245:120540. [PMID: 37688851 DOI: 10.1016/j.watres.2023.120540] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 08/25/2023] [Accepted: 08/27/2023] [Indexed: 09/11/2023]
Abstract
Side-stream enhanced biological phosphorus removal process (S2EBPR) has been demonstrated to improve performance stability and offers a suite of advantages compared to conventional EBPR design. Design and optimization of S2EBPR require modification of the current EBPR models that were not able to fully reflect the metabolic functions of and competition between the polyphosphate-accumulating organisms (PAOs) and glycogen-accumulating organisms (GAOs) under extended anaerobic conditions as in the S2EBPR conditions. In this study, we proposed and validated an improved model (iEBPR) for simulating PAO and GAO competition that incorporated heterogeneity and versatility in PAO sequential polymer usage, staged maintenance-decay, and glycolysis-TCA pathway shifts. The iEBPR model was first calibrated against bulk batch testing experiment data and proved to perform better than the previous EBPR model for predicting the soluble orthoP, ammonia, biomass glycogen, and PHA temporal profiles in a starvation batch testing under prolonged anaerobic conditions. We further validated the model with another independent set of anaerobic testing data that included high-resolution single-cell and specific population level intracellular polymer measurements acquired with single-cell Raman micro-spectroscopy technique. The model accurately predicted the temporal changes in the intracellular polymers at cellular and population levels within PAOs and GAOs, and further confirmed the proposed mechanism of sequential polymer utilization, and polymer availability-dependent and staged maintenance-decay in PAOs. These results indicate that under extended anaerobic phases as in S2EBPR, the PAOs may gain competitive advantages over GAOs due to the possession of multiple intracellular polymers and the adaptive switching of the anaerobic metabolic pathways that consequently lead to the later and slower decay in PAOs than GAOs. The iEBPR model can be applied to facilitate and optimize the design and operations of S2EBPR for more reliable nutrient removal and recovery from wastewater.
Collapse
Affiliation(s)
- Guangyu Li
- Department of Civil & Environmental Engineering, Northeastern University, Boston, MA, United States; School of Civil and Environmental Engineering, Cornell University, Ithaca, NY, United States
| | - Nicholas B Tooker
- Department of Civil & Environmental Engineering, Northeastern University, Boston, MA, United States
| | - Dongqi Wang
- Department of Civil & Environmental Engineering, Northeastern University, Boston, MA, United States; Department of Municipal and Environmental Engineering, Xi'an University of Technology, Xi'an, Shaanxi, China
| | - Varun Srinivasan
- Department of Civil & Environmental Engineering, Northeastern University, Boston, MA, United States; Brown and Caldwell, One Tech Drive, Andover, MA, United States
| | | | - Andrew Russell
- South Cary Water Reclamation Facility, Apex, NC, United States
| | | | | | | | | | - Erika Varga
- LISBP, INSA Toulouse, Toulouse, France; Dynamita, Nyons, France
| | | | | | - Charles Bott
- Hampton Roads Sanitation District, Virginia Beach, VA, United States
| | | | - Annalisa Onnis-Hayden
- Department of Civil & Environmental Engineering, Northeastern University, Boston, MA, United States
| | - April Z Gu
- Department of Civil & Environmental Engineering, Northeastern University, Boston, MA, United States; School of Civil and Environmental Engineering, Cornell University, Ithaca, NY, United States.
| |
Collapse
|
5
|
Li J, Peng Y, Yang S, Li S, Feng W, Li X, Zhang Q, Zhang L. Successful Application of Anammox Using the Hybrid Autotrophic-Heterotrophic Denitrification Process for Low-Strength Wastewater Treatment. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:13964-13974. [PMID: 36000687 DOI: 10.1021/acs.est.2c02920] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Directly integrating anammox into sewage treatment is attractive, but anammox bacteria (AnAOB) enrichment is complex due to vicious competition from heterotrophic bacteria (HB). A novel strategy of optimal organics management using a preanaerobic stage and subsequent limited-oxygen conditions (0.32 ± 0.15 mg-O2/L) is applied, and a hybrid autotrophic-heterotrophic denitrification process is developed to treat sewage-like wastewater with a COD/N ratio of 3.1 for 420 days. The stable process was achieved, and a high total nitrogen removal rate of 0.53 kg-N/(m3·d) was obtained compared to conventional nitrification/denitrification. The 16S rRNA high-throughput sequencing analysis suggested that the relative abundance of the nonendogenous HB (Denitratisoma and Thauera) was drastically reduced (P ≤ 0.001), whereas the endogenous denitrifying HB (Candidatus (Ca.) Competibacter) was significantly enriched in the anammox granules (9.98%, P ≤ 0.001). Moreover, Ca. Competibacter as an inner core and Nitrospira and Ca. Brocadia as an outside coating of the anammox granules indicated the cooperation of AnAOB with HB as revealed by laser-scanning confocal microscopy and qPCR. In situ tests further confirmed nitrite from two pathways (partial nitritation and endogenous partial denitritation) that favored AnAOB enrichment. Optimal organics management can mitigate the competition of HB with AnAOB by redirecting the metabolic pathways and microbial community, which is critical to directly integrating anammox into sewage treatment.
Collapse
Affiliation(s)
- Jialin Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - 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
| | - Shenhua Yang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Shuai 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
| | - Wanyi Feng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - 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
| |
Collapse
|
6
|
Li Z, Wang J, Chen X, Lei Z, Yuan T, Shimizu K, Zhang Z, Lee DJ. Insight into aerobic phosphorus removal from wastewater in algal-bacterial aerobic granular sludge system. BIORESOURCE TECHNOLOGY 2022; 352:127104. [PMID: 35378284 DOI: 10.1016/j.biortech.2022.127104] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 03/29/2022] [Accepted: 03/30/2022] [Indexed: 06/14/2023]
Abstract
This study aimed to figure out the main contributors to aerobic phosphorus (P) removal in the algal-bacterial aerobic granular sludge (AGS)-based wastewater treatment system. Kinetics study showed that aerobic P removal was controlled by macropore (contributing to 64-75% P removal) and micropore diffusion, and the different light intensity (0, 4.0, 12.3, and 24.4 klux) didn't exert significant (p > 0.05) influence on P removal. On the other hand, the increasing light intensity did promote microalgae metabolism, leading to the elevated wastewater pH (8.0-9.8). The resultant pH increase had a strongly negative relationship (R2 = 0.9723) with P uptake by polyphosphate-accumulating organisms, while promoted chemical Ca-P precipitation at a molar Ca/P ratio of 1.05. Results from this work could provide an in-depth understanding of microalgae-bacteria symbiotic interaction, which is helpful to better design and operate the algal-bacterial AGS systems.
Collapse
Affiliation(s)
- Zejiao Li
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Jixiang Wang
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Xingyu Chen
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Zhongfang Lei
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan.
| | - Tian Yuan
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Kazuya Shimizu
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Zhenya Zhang
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Duu-Jong Lee
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan; Department of Mechanical Engineering, City University of Hong Kong, Kowloon Tang, Hong Kong
| |
Collapse
|
7
|
Wang J, Li Z, Wang Q, Lei Z, Yuan T, Shimizu K, Zhang Z, Adachi Y, Lee DJ, Chen R. Achieving stably enhanced biological phosphorus removal from aerobic granular sludge system via phosphorus rich liquid extraction during anaerobic period. BIORESOURCE TECHNOLOGY 2022; 346:126439. [PMID: 34848332 DOI: 10.1016/j.biortech.2021.126439] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 11/22/2021] [Accepted: 11/24/2021] [Indexed: 06/13/2023]
Abstract
In order to sustainably manage wastewater treatment plants and the environment, enhanced biological phosphorus (P) removal (EBPR) was proposed to achieve P recovery through extracting P-rich liquid (i.e., Phostrip) from the bottom of aerobic granular sludge (AGS)-based sequencing batch reactors (SBRs) under no mixing during the anaerobic phase. Results showed both tested bacterial AGS (BAGS) and algal-bacterial AGS (A-BAGS) systems stably produced low effluent P (<0.05 mg-P/L) with little impact on their organics and NH4+-N removals (>99%). The collected P-rich liquids (55-83 mg-P/L) from both systems showed great potential for P recovery of about 83.85 ± 0.57 % (BAGS) or 83.99 ± 0.77% (A-BAGS), which were contributed by the influent P (>95%) and P reserves in granules based on P balance analysis. This study suggests that the AGS-based SBRs coupling the Phostrip holds great potentials for P recovery profit and further reduction in energy consumption.
Collapse
Affiliation(s)
- Jixiang Wang
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1, Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Zejiao Li
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1, Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Qian Wang
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1, Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Zhongfang Lei
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1, Tennodai, Tsukuba, Ibaraki 305-8572, Japan.
| | - Tian Yuan
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1, Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Kazuya Shimizu
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1, Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Zhenya Zhang
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1, Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Yasuhisa Adachi
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1, Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Duu-Jong Lee
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan; Department of Mechanical Engineering, City University of Hong Kong, Kowloon Tang, Hong Kong
| | - Rongzhi Chen
- College of Resources and Environment, University of Chinese Academy of Sciences, Yuquan Road 19A, Beijing 100049, PR China
| |
Collapse
|
8
|
Comparative Study on Using Various Recovery Stimulation Methods to Boost Nitrification Recovery in SBRs Inhibited by Hazardous Events. WATER 2021. [DOI: 10.3390/w14010048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A system consisting of six SBR units was operated in parallel for three phases to investigate the impacts of salinity shock and anaerobic and aerobic starvation on the activated sludge process stability and effects of various recovery stimulation methods on the subsequent recovery period. Different recovery strategies were applied in each SBR unit, including natural recovery, adding bio-accelerators, a stepwise increase feed strategy, a stepwise strategy coupled with bio-accelerators dosing, extended aeration time, and extended aeration time coupled with bio-accelerators dosing. It was concluded that the combination of stepwise strategy and dosing bio-accelerators showed the most efficiency in boosting system recovery after being subjected to NaCl shock and starvation. The boosting effect of the stepwise strategy alone was slightly better in recovery after NaCl shock. Furthermore, extending the aeration rate could bring more positive effects when resuscitating the system after long-term anaerobic starvation. For the unit that only received dosing of bio-accelerators during the recovery period, it could be concluded that there was a specific time requirement for the bio-accelerators to take effect significantly, as the impact of bio-accelerators on the beginning days of recovery periods was very slight. In contrast, adjusting operational regimes such as stepwise increased feed volume or extending aeration time could significantly boost the SBRs from the first recovery days. Hence, highly effective recovery efficiency could be achieved by coupling dosing bio-accelerators with other operational adjustment methods, especially stepwise strategies.
Collapse
|
9
|
Okabe S, Kamigaito A, Kobayashi K. Maintenance power requirements of anammox bacteria "Candidatus Brocadia sinica" and "Candidatus Scalindua sp.". THE ISME JOURNAL 2021; 15:3566-3575. [PMID: 34145389 PMCID: PMC8629980 DOI: 10.1038/s41396-021-01031-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 05/27/2021] [Accepted: 06/02/2021] [Indexed: 02/05/2023]
Abstract
Little is known about the cell physiology of anammox bacteria growing at extremely low growth rates. Here, "Candidatus Brocadia sinica" and "Candidatus Scalindua sp." were grown in continuous anaerobic membrane bioreactors (MBRs) with complete biomass retention to determine maintenance energy (i.e., power) requirements at near-zero growth rates. After prolonged retentostat cultivations, the specific growth rates (μ) of "Ca. B. sinica" and "Ca. Scalindua sp." decreased to 0.000023 h-1 (doubling time of 1255 days) and 0.000157 h-1 (184 days), respectively. Under these near-zero growth conditions, substrate was continuously utilized to meet maintenance energy demands (me) of 6.7 ± 0.7 and 4.3 ± 0.7 kJ mole of biomass-C-1 h-1 for "Ca. B. sinica" and "Ca. Scalindua sp.", which accorded with the theoretically predicted values of all anaerobic microorganisms (9.7 and 4.4 kJ mole of biomass-C-1 h-1at 37 °C and 28 °C, respectively). These me values correspond to 13.4 × 10-15 and 8.6 × 10-15 watts cell-1 for "Ca. B. sinica" and "Ca. Scalindua sp.", which were five orders of magnitude higher than the basal power limit for natural settings (1.9 × 10-19 watts cells-1). Furthermore, the minimum substrate concentrations required for growth (Smin) were calculated to be 3.69 ± 0.21 and 0.09 ± 0.05 μM NO2- for "Ca. B. sinica" and "Ca. Scalindua sp.", respectively. These results match the evidence that "Ca. Scalindua sp." with lower maintenance power requirement and Smin are better adapted to energy-limited natural environments than "Ca. B. sinica", suggesting the importance of these parameters on ecological niche differentiation in natural environments.
Collapse
Affiliation(s)
- Satoshi Okabe
- grid.39158.360000 0001 2173 7691Department of Environmental Engineering, Faculty of Engineering, Hokkaido University, North 13, West 8, Sapporo, Hokkaido, 060-8628 Japan
| | - Atsushi Kamigaito
- grid.39158.360000 0001 2173 7691Department of Environmental Engineering, Faculty of Engineering, Hokkaido University, North 13, West 8, Sapporo, Hokkaido, 060-8628 Japan
| | - Kanae Kobayashi
- grid.39158.360000 0001 2173 7691Department of Environmental Engineering, Faculty of Engineering, Hokkaido University, North 13, West 8, Sapporo, Hokkaido, 060-8628 Japan
| |
Collapse
|
10
|
Liu W, Li J, Peng Y. Impact of starvation conditions on the nitrifying performance and sludge properties in SBR system with a limited filamentous bulking state. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 797:148997. [PMID: 34346374 DOI: 10.1016/j.scitotenv.2021.148997] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Revised: 06/30/2021] [Accepted: 07/08/2021] [Indexed: 06/13/2023]
Abstract
Limited filamentous bulking (LFB) induced by low dissolved oxygen in activated sludge system is an effective energy saving process. However, starvation environment is liable to result in the unbalance between filaments and flocs, affecting the LFB system performance. The variations in nitrifying performance and properties of LFB sludge during 14 days of four starvation conditions (aerobic, alternating anaerobic/aerobic, anaerobic and anoxic) and their subsequent recovery were investigated in sequencing batch reactor (SBR) system. The results showed that the highest activity decay rates of ammonia- and nitrite-oxidizing bacteria (AOB and NOB) were observed under aerobic starvation condition, followed by anoxic, anaerobic, and alternating anaerobic/aerobic starvation conditions. In the reactivation period, the faster recovery of AOB activity and cell number, relative to NOB, particularly in aerobic case, led to temporary nitrite accumulation. Besides, the sludge settleability rapidly improved (SVI of ~30 mL/g) due to filamentous bacteria suppression under aerobic starvation, while the filaments (e.g. Type 0092) overgrew (SVI of ~250 mL/g) under anoxic starvation, triggering unexpected biomass loss and going against the nitrifying performance recovery of the system. In contrast, alternating anaerobic/aerobic and anaerobic starvations avoid pure aerobic or anoxic starvation condition, effectively maintaining the nitrifying performance and LFB state, and therefore are the best storage strategies for LFB sludge.
Collapse
Affiliation(s)
- Wenlong Liu
- College of Environment, Zhejiang University of Technology, Hangzhou 310014, China; National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | - Jun Li
- College of Environment, Zhejiang University of Technology, Hangzhou 310014, China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China.
| |
Collapse
|
11
|
Carvalho VCF, Kessler M, Fradinho JC, Oehmen A, Reis MAM. Achieving nitrogen and phosphorus removal at low C/N ratios without aeration through a novel phototrophic process. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 793:148501. [PMID: 34171805 DOI: 10.1016/j.scitotenv.2021.148501] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 06/12/2021] [Accepted: 06/13/2021] [Indexed: 06/13/2023]
Abstract
Conventional wastewater treatment technologies for biological nutrient removal (BNR) are highly dependent on aeration for oxygen supply, which represents a major operational cost of the process. Recently, phototrophic enhanced biological phosphorus removal (photo-EBPR) has been suggested as an alternative system for phosphorus removal, based on a consortium of photosynthetic microorganisms and chemotrophic bacteria, eliminating the need for costly aeration. However, wastewater treatment plants must couple nitrogen and phosphorus removal to achieve discharge limits. For this reason, a new microalgae-bacterial based system for phosphorus and nitrogen removal is proposed in this work. The photo-BNR system studied here consists of a sequencing batch reactor operated with dark anaerobic, light aerobic, dark anoxic and idle periods, to allow both N and P removal. Results of the study show that the photo-BNR system was able to remove 100% of the 40 mg N/L of ammonia fed to the reactor and 94 ± 3% of the total nitrogen (Influent COD:N ratio of 300:40, similar to domestic wastewater). Moreover, an average of 25 ± 9.2 mg P/L was simultaneously removed in the photo-BNR tests, representing the P removal capacity of this system, which exceeds the level of P removal required from typical domestic wastewater. Full ammonia removal was achieved during the light phase, with 67 ± 5% of this ammonia being assimilated by the microbial culture and the remaining 33 ± 5% being converted into nitrate. The assimilated P corresponded to 2.8 ± 0.23 mg P/L, which only represented, approximately, 1/9 of the P removal capacity of the system. Half of the nitrified ammonia was subsequently denitrified during the dark anoxic phase (50 ± 24%). Overall, the photo-BNR system represents the first treatment alternative for N and P from domestic wastewater with no need of mechanical aeration or supplemental carbon addition, representing an alternative low-energy technology of interest.
Collapse
Affiliation(s)
- V C F Carvalho
- UCIBIO-REQUIMTE, Department of Chemistry, Faculty of Sciences and Technology, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal
| | - M Kessler
- UCIBIO-REQUIMTE, Department of Chemistry, Faculty of Sciences and Technology, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal
| | - J C Fradinho
- UCIBIO-REQUIMTE, Department of Chemistry, Faculty of Sciences and Technology, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal.
| | - A Oehmen
- School of Chemical Engineering, University of Queensland, Brisbane, QLD 4072, Australia
| | - M A M Reis
- UCIBIO-REQUIMTE, Department of Chemistry, Faculty of Sciences and Technology, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal
| |
Collapse
|
12
|
Shekhar Bose R, Zakaria BS, Kumar Tiwari M, Ranjan Dhar B. High-rate blackwater anaerobic digestion under septic tank conditions with the amendment of biosolids-derived biochar synthesized at different temperatures. BIORESOURCE TECHNOLOGY 2021; 331:125052. [PMID: 33812134 DOI: 10.1016/j.biortech.2021.125052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 03/18/2021] [Accepted: 03/19/2021] [Indexed: 06/12/2023]
Abstract
Septic tanks have been widely used for blackwater treatment in developing countries, while high-rate septic tanks with improved methane recovery are yet to be achieved. This study investigated biosolids-derived biochar (synthesized at 300℃, 425℃, and 550℃) as an additive for developing high-rate septic tanks. The experiments were conducted with anaerobic bioreactors operated with synthetic blackwater under septic tank conditions. All biochar amended reactors demonstrated a steady increase in daily methane production for increasing OLR from 0.08 to 3 g COD/L/d. The control reactor showed significant process disturbances at OLRs ≥ 2 g COD/L/d with an accumulation of volatile fatty acids followed by pH drop. At OLR of 3 g COD/L/d, the daily methane production from biochar amended reactors was ~ 4.3 times higher than the control (300 vs. 70 mL per day). Biochar addition established a robust microbiome consisted of a higher abundance of hydrogenotrophic and acetoclastic methanogens and hydrogen-producing fermentative bacteria.
Collapse
Affiliation(s)
- Raj Shekhar Bose
- Civil and Environmental Engineering, University of Alberta, Edmonton, AB, Canada; School of Water Resources, Indian Institute of Technology Kharagpur, WB, India
| | - Basem S Zakaria
- Civil and Environmental Engineering, University of Alberta, Edmonton, AB, Canada
| | - Manoj Kumar Tiwari
- School of Water Resources, Indian Institute of Technology Kharagpur, WB, India
| | - Bipro Ranjan Dhar
- Civil and Environmental Engineering, University of Alberta, Edmonton, AB, Canada.
| |
Collapse
|
13
|
Duque AF, Bessa VS, van Dongen U, de Kreuk MK, Mesquita RBR, Rangel AOSS, van Loosdrecht MCM, Castro PML. Simultaneous nitrification and phosphate removal by bioaugmented aerobic granules treating a fluoroorganic compound. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2021; 83:2404-2413. [PMID: 34032618 DOI: 10.2166/wst.2021.142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The presence of toxic compounds in wastewater can cause problems for organic matter and nutrient removal. In this study, the long-term effect of a model xenobiotic, 2-fluorophenol (2-FP), on ammonia-oxidizing bacteria (AOB), nitrite oxidizing bacteria (NOB) and phosphate accumulating organisms (PAO) in aerobic granular sludge was investigated. Phosphate (P) and ammonium (N) removal efficiencies were high (>93%) and, after bioaugmentation with 2-FP degrading strain FP1, 2-FP was completely degraded. Neither N nor P removal were affected by 50 mg L-1 of 2-FP in the feed stream. Changes in the aerobic granule bacterial communities were followed. Numerical analysis of the denaturing gradient gel electrophoresis (DGGE) profiles showed low diversity for the ammonia monooxygenase (amoA) gene with an even distribution of species. PAOs, including denitrifying PAO (dPAO), and AOB were present in the 2-FP degrading granules, although dPAO population decreased throughout the 444 days reactor operation. The results demonstrated that the aerobic granules bioaugmented with FP1 strain successfully removed N, P and 2-FP simultaneously.
Collapse
Affiliation(s)
- Anouk F Duque
- Universidade Católica Portuguesa, CBQF - Centro de Biotecnologia e Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, 4169-005 Porto, Portugal E-mail: ; † Present address: UCIBIO-REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal
| | - Vânia S Bessa
- Universidade Católica Portuguesa, CBQF - Centro de Biotecnologia e Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, 4169-005 Porto, Portugal E-mail:
| | - Udo van Dongen
- Department of Biotechnology, Delft University of Technology, van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Merle K de Kreuk
- Section Sanitary Engineering, Department of Water Management, Delft University of Technology, Stevinweg 1, 2628 CN, Delft, The Netherlands
| | - Raquel B R Mesquita
- Universidade Católica Portuguesa, CBQF - Centro de Biotecnologia e Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, 4169-005 Porto, Portugal E-mail:
| | - António O S S Rangel
- Universidade Católica Portuguesa, CBQF - Centro de Biotecnologia e Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, 4169-005 Porto, Portugal E-mail:
| | - Mark C M van Loosdrecht
- Department of Biotechnology, Delft University of Technology, van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Paula M L Castro
- Universidade Católica Portuguesa, CBQF - Centro de Biotecnologia e Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, 4169-005 Porto, Portugal E-mail:
| |
Collapse
|
14
|
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.
Collapse
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
| |
Collapse
|
15
|
Immobilization of Phosphatidylserine by Ethanol and Lysozyme on the Cell Surface for Evaluation of Apoptosis-Like Decay in Activated-Sludge Bacteria. Appl Environ Microbiol 2020; 86:AEM.00345-20. [PMID: 32414801 DOI: 10.1128/aem.00345-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 04/30/2020] [Indexed: 01/18/2023] Open
Abstract
Accurate determination of microbial viability can be crucial in microbe-dominated biosystems. However, the identification of metabolic decay in bacterial cells can be elaborate and difficult. We sought to identify apoptosis-like bacterial processes by using annexin V-fluorescein isothiocyanate (FITC) (AVF), a probe typically used to stain phosphatidylserine (PS) on exposed cell membranes. The bacterial cell wall provides a barrier that is responsible for low efficiency of direct PS staining of decayed bacterial cells. This can be overcome by pretreatment of the bacteria with 70% ethanol, which fixates the bacteria and preserves the PS status, combined with lysozyme treatment to hydrolyze the cell wall. That treatment improved the efficiency of AVF staining considerably, as shown for pure strains of an Ochrobactrum sp. and a Micrococcus sp. Using this method, decayed bacterial cells (induced by starvation) were more strongly stained, indicating externalization of PS to a greater extent than seen for cells harvested at logarithmic growth. A multispecies microbial sludge was artificially decayed by heat treatment or alternating anoxic-oxic treatment, which also induced increased AVF staining, again presumably via decay-related PS externalization. The method developed proved to be efficient for identification of bacterial decay and has potential for the evaluation of multispecies bacterial samples from sources like soil matrix, bioaerosol, and activated sludge.IMPORTANCE Since the externalization of phosphatidylserine (PS) is considered a crucial characteristic of apoptosis, we sought to identify apoptosis-like decay in bacterial cells by PS staining using AVF. We show that this is possible, provided the bacteria are pretreated with ethanol plus lysozyme to remove a physical staining barrier and preserve the original, decay-related externalization of PS. Our work suggests that PS externalization occurs in starved bacteria and this can be quantified with AVF staining, providing a measure of bacterial decay. Since PS is the common component of the lipid bilayer in bacterial cell membranes, this approach also has potential for evaluation of cell decay of other bacterial species.
Collapse
|
16
|
Liu B, Li Y, Wu J, Shao Y, Chen F, Wu JH, Goel R, Terashima M, Yasui H. Evaluating nitrite oxidizing organism survival under different nitrite concentrations. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2020; 82:273-280. [PMID: 32941169 DOI: 10.2166/wst.2020.138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The objective of this study is to explore the optimal pre-treatment procedures and statistics methods for live/dead bacterial staining using nitrite oxidizing organism (NOO) as the research aim. This staining method was developed and widely utilized to evaluate activated bacterial survival situation, because it is direct and convenience to count live and dead bacteria amount by colour distinguishes (green/red) from pictures taken by microscope. The living cell (green colour) percentage and initial bacterial chemical oxygen demand (COD) could be used for accurate reaction rate calculation at the beginning of tests. While according to the physiological principles, the detection target was limited as the organism has a complete cell shape, that was applicable for the initial phase for decay stage (live cell → particulate dead cell), but it is impossible to evaluate the decayed soluble COD from particulate dead cell during whole reaction. To model the decay stage scientifically, a two-step decay model was developed to cater to the live/dead bacterial staining analysis of biological nitrite oxidizer under inhibition condition of high nitrite concentrations at 35 °C. As results of optimal pre-treatment, a three level ultrasonic wave with 45 seconds was explored, as a reasonable observed picture number, 30 sets with 95% confident interval for datasets statistics was summarized. A set of nitrite oxidizer inhibition test (total COD and oxygen uptake rates) under high nitrite concentrations was simulated using the above model and obtained experimental schemes. Additionally, the disintegration enhancement from particulate dead cell to soluble COD by nitrite was inspected and modelled on the basis of experimental datasets.
Collapse
Affiliation(s)
- Bing Liu
- Resources and Environment Innovation Institute, School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan, 250101, China E-mail: ; Faculty of Environmental Engineering, University of Kitakyushu, 1-1, Hibikino, Wakamatsu, Kitakyushu, 808-0135, Japan
| | - Yifan Li
- Resources and Environment Innovation Institute, School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan, 250101, China E-mail:
| | - Jinzhu Wu
- Resources and Environment Innovation Institute, School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan, 250101, China E-mail:
| | - Yuanyuan Shao
- Resources and Environment Innovation Institute, School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan, 250101, China E-mail:
| | - Feiyong Chen
- Resources and Environment Innovation Institute, School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan, 250101, China E-mail:
| | - Jer-Horng Wu
- Department of Environmental Engineering, National Cheng Kung University, No. 1 University Road, East District, Taiwan City 701, Taiwan
| | - Rajeev Goel
- Hydromantis Environmental Software Solutions Inc., Suite 1601, 1 James Street South, Hamilton, Ontario L8P4R5, Canada
| | - Mitsuharu Terashima
- Faculty of Environmental Engineering, University of Kitakyushu, 1-1, Hibikino, Wakamatsu, Kitakyushu, 808-0135, Japan
| | - Hidenari Yasui
- Faculty of Environmental Engineering, University of Kitakyushu, 1-1, Hibikino, Wakamatsu, Kitakyushu, 808-0135, Japan
| |
Collapse
|
17
|
Santos JMM, Rieger L, Lanham AB, Carvalheira M, Reis MAM, Oehmen A. A novel metabolic-ASM model for full-scale biological nutrient removal systems. WATER RESEARCH 2020; 171:115373. [PMID: 31846822 DOI: 10.1016/j.watres.2019.115373] [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: 08/02/2019] [Revised: 11/23/2019] [Accepted: 12/05/2019] [Indexed: 06/10/2023]
Abstract
This study demonstrates that META-ASM, a new integrated metabolic activated sludge model, provides an overall platform to describe the activity of the key organisms and processes relevant to biological nutrient removal (BNR) systems with a robust single-set of default parameters. This model overcomes various shortcomings of existing enhanced biological phosphorous removal (EBPR) models studied over the last twenty years. The model has been tested against 34 data sets from enriched lab polyphosphate accumulating organism (PAO)-glycogen accumulating organism (GAO) cultures and experiments with full-scale sludge from five water resource recovery facilities (WRRFs) with two different process configurations: three stage Phoredox (A2/O) and adapted Biodenitro™ combined with a return sludge sidestream hydrolysis tank (RSS). Special attention is given to the operational conditions affecting the competition between PAOs and GAOs, capability of PAOs and GAOs to denitrify, metabolic shifts as a function of storage polymer concentrations, as well as the role of these polymers in endogenous processes and fermentation. The overall good correlations obtained between the predicted versus measured EBPR profiles from different data sets support that this new model, which is based on in-depth understanding of EBPR, reduces calibration efforts. On the other hand, the performance comparison between META-ASM and literature models demonstrates that existing literature models require extensive parameter changes and have limited predictive power, especially in the prediction of long-term EBPR performance. The development of such a model able to describe in detail the microbial and chemical transformations of BNR systems with minimal adjustment to parameters suggests that the META-ASM model is a powerful tool to predict and mitigate EBPR upsets, optimise EBPR performance and to evaluate new process designs.
Collapse
Affiliation(s)
- Jorge M M Santos
- UCIBIO-REQUIMTE, Chemistry Department, Faculty of Sciences and Tecnology, Universidade NOVA de Lisboa, Campus de Caparica, 2829-516, Caparica, Portugal.
| | | | - Ana B Lanham
- UCIBIO-REQUIMTE, Chemistry Department, Faculty of Sciences and Tecnology, Universidade NOVA de Lisboa, Campus de Caparica, 2829-516, Caparica, Portugal
| | - Mónica Carvalheira
- UCIBIO-REQUIMTE, Chemistry Department, Faculty of Sciences and Tecnology, Universidade NOVA de Lisboa, Campus de Caparica, 2829-516, Caparica, Portugal
| | - Maria A M Reis
- UCIBIO-REQUIMTE, Chemistry Department, Faculty of Sciences and Tecnology, Universidade NOVA de Lisboa, Campus de Caparica, 2829-516, Caparica, Portugal
| | - Adrian Oehmen
- UCIBIO-REQUIMTE, Chemistry Department, Faculty of Sciences and Tecnology, Universidade NOVA de Lisboa, Campus de Caparica, 2829-516, Caparica, Portugal
| |
Collapse
|
18
|
Liu W, Lian J, Guo J, Zhang C, Guo Y, Niu Y, Duan L. Perchlorate reduction by anaerobic granular sludge under different operation strategies: Performance, extracellular polymeric substances and microbial community. ACTA ACUST UNITED AC 2019. [DOI: 10.1016/j.biteb.2019.100312] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
19
|
Hou L, Griswold N, Ji J, Hu Z. Specific affinity and relative abundance of methanogens in acclimated anaerobic sludge treating low-strength wastewater. Appl Microbiol Biotechnol 2019; 104:291-302. [PMID: 31732752 DOI: 10.1007/s00253-019-10149-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 08/20/2019] [Accepted: 09/22/2019] [Indexed: 11/26/2022]
Abstract
Kinetic parameters affecting effluent water quality including half saturation constant (Ks), maximum specific growth rate (μmax), and specific affinity ([Formula: see text], defined as μmax/Ks) were investigated using three types of anaerobic sludge (raw anaerobic digestion sludge referred to as unacclimated sludge, unacclimated sludge after endogenous decay, and sludge acclimated to low-strength wastewater in an anaerobic membrane bioreactor (AnMBR) for 360 days). Long-term acclimation to low-strength wastewater resulted in sludge with high specific affinity (1.6 × 10-3 L/mg COD/day for acclimated sludge compared to 4.1 × 10-4 L/mg COD/day for unacclimated sludge). The μmax values for unacclimated sludge and acclimated sludge were 0.08 and 0.07 day-1, respectively. The Ks values for unacclimated sludge and acclimated sludge were 194 ± 81 mg COD/L and 45 ± 13 mg COD/L, respectively. Although the Ks of unacclimated sludge after endogenous decay increased to 772 ± 74 mg COD/L, μmax increased to 0.35 day-1 as well, resulting in no statistically significant difference of [Formula: see text] between the two types of unacclimated sludge. Overall, [Formula: see text] is a better indicator than μmax or Ks alone for determining effluent water quality, as effluent substrate concentration is approximately inversely proportional to the specific affinity. 16S rRNA sequencing data analysis indicated a high abundance (85.8% of total archaea) of Methanosaeta in the microbial community after long-term acclimation. High [Formula: see text] associated with the enrichment of Methanosaeta appears to ensure successful anaerobic treatment of low-strength wastewater.
Collapse
Affiliation(s)
- Liyuan Hou
- Department of Civil and Environmental Engineering, University of Missouri, E2509 Lafferre Hall, Columbia, MO, 65211, USA
| | - Nick Griswold
- Department of Civil and Environmental Engineering, University of Missouri, E2509 Lafferre Hall, Columbia, MO, 65211, USA
| | - Junyuan Ji
- Key Laboratory of Marine Environment and Ecology, Ministry of Education, Ocean University of China, Qingdao, 266000, China.
- College of Environmental Science and Engineering, Ocean University of China, 238 Songling Road, Laoshan District, Qingdao, 266100, China.
| | - Zhiqiang Hu
- Department of Civil and Environmental Engineering, University of Missouri, E2509 Lafferre Hall, Columbia, MO, 65211, USA.
| |
Collapse
|
20
|
Wang B, Wu D, Dai J, Ekama GA, Hao X, Chen GH. Elucidating the effects of starvation and reactivation on anaerobic sulfidogenic granular sludge: Reactor performance and granular sludge transformation. WATER RESEARCH 2019; 151:44-53. [PMID: 30594089 DOI: 10.1016/j.watres.2018.12.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 11/10/2018] [Accepted: 12/04/2018] [Indexed: 06/09/2023]
Abstract
In biological wastewater treatment, the bacteria starvation always challenges the stability of system operation. Yet, the effects of starvation and possibility of reactivation are less understood for anaerobic sulfidogenic system. Sulfidogenic systems use sulfate as electron acceptor for organic chemical oxygen demand (COD) degradation, so it will encounter two kind of starvations: (i) complete stoppage of wastewater flow (named complete food starvation) and (ii) remaining organic COD but with very low level sulfate in the influent (named sulfate starvation). In this study, the relative long-term starvation (over 30-day) and subsequent reactivation were studied in two lab-scale continuous gas recirculation sulfate-reducing upflow sludge bed (CGR-SRUSB) reactors. It was observed that the complete food starvation and sulfate starvation decreased the COD removal rate (in the similar range of 60-65%) and the specific sulfidogenic activity (about 45% and 61% respectively), as well as increasing the sludge flotation potential (SFP) from <15% to 58% and 35% respectively. Moreover, the following restoration experiments proved that the perturbed systems could be reactivated within 10-15 days for both cases. The results of investigating the mechanisms showed the performance deterioration were highly attributed to the starvation-induced granular sludge transitions, with respect to the changing of sludge physico-chemical properties (permeability, porosity, hydrophobicity and viscocity) and microbial stuctures (sulfate-reducting bacteria and extracellular polymeric substances). The outcomes of this study can provide useful information for dealing with the prolonged starvation problems in sulfidogenesis-based systems in industrial and municipal wastewater treatment.
Collapse
Affiliation(s)
- Bo Wang
- Department of Civil and Environmental Engineering, Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution (Hong Kong Branch), and Water Technology Center, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Di Wu
- Department of Civil and Environmental Engineering, Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution (Hong Kong Branch), and Water Technology Center, The Hong Kong University of Science and Technology, Hong Kong, China; Wastewater Treatment Laboratory, FYT Graduate School, and Shenzhen Institute, The Hong Kong University of Science and Technology, Guangdong, China.
| | - Ji Dai
- Department of Civil and Environmental Engineering, Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution (Hong Kong Branch), and Water Technology Center, The Hong Kong University of Science and Technology, Hong Kong, China
| | - George A Ekama
- Water Research Group, Department of Civil Engineering, University of Cape Town, Cape Town, South Africa
| | - Xiaodi Hao
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies/Key Laboratory of Urban Stormwater System and Water Environment, Beijing University of Civil Engineering & Architecture, Beijing, 100044, PR China
| | - Guang-Hao Chen
- Department of Civil and Environmental Engineering, Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution (Hong Kong Branch), and Water Technology Center, The Hong Kong University of Science and Technology, Hong Kong, China; Wastewater Treatment Laboratory, FYT Graduate School, and Shenzhen Institute, The Hong Kong University of Science and Technology, Guangdong, China
| |
Collapse
|
21
|
Takizawa S, Baba Y, Tada C, Fukuda Y, Nakai Y. Preservation of rumen fluid for the pretreatment of waste paper to improve methane production. WASTE MANAGEMENT (NEW YORK, N.Y.) 2019; 87:672-678. [PMID: 31109569 DOI: 10.1016/j.wasman.2019.02.043] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 01/31/2019] [Accepted: 02/21/2019] [Indexed: 06/09/2023]
Abstract
It is necessary to preserve rumen fluid for transport from slaughterhouses to the pretreatment facilities for use in treating lignocellulosic biomass. In this study, we investigated how the preservation of rumen fluid at various temperatures affects its use in hydrolysis of waste paper. Rumen fluid was preserved anaerobically at 4, 20, and 35 °C for 7 days. The number of protozoa and fibrolytic enzyme activity after preservation at 4 °C were significantly higher than that after preservation at either 20 or 35 °C. Waste paper was subsequently treated with preserved rumen fluid at 37 °C for 48 h. Preservation at 20 °C remarkedly decreased the hydrolysis of waste paper. Xylanase activity in rumen fluid preserved at 35 °C increased during the treatment, which enhanced the solubilization of waste paper as comparable to the control and preservation at 4 °C. Pretreatment of waste paper with rumen fluid preserved at 4 °C showed that the fluid retained high fibrolytic activity, and reduced the loss of organic carbon as substrate for methanogens. Our results suggest that preservation of rumen fluid at 4 °C is most suitable for efficient pretreatment and methane fermentation of waste paper.
Collapse
Affiliation(s)
- Shuhei Takizawa
- Laboratory of Sustainable Animal Environment, Graduate School of Agricultural Science, Tohoku University, Yomogida 232-3, Naruko-onsen, Osaki, Miyagi 989-6711, Japan
| | - Yasunori Baba
- Research Institute for Bioresources and Biotechnology, Ishikawa Prefectural University, Suematsu 1-308, Nonoichi, Ishikawa 921-8836, Japan
| | - Chika Tada
- Laboratory of Sustainable Animal Environment, Graduate School of Agricultural Science, Tohoku University, Yomogida 232-3, Naruko-onsen, Osaki, Miyagi 989-6711, Japan.
| | - Yasuhiro Fukuda
- Laboratory of Sustainable Animal Environment, Graduate School of Agricultural Science, Tohoku University, Yomogida 232-3, Naruko-onsen, Osaki, Miyagi 989-6711, Japan
| | - Yutaka Nakai
- Department of Agro-Food Science, Niigata Agro-Food University, Hiranedai 2416, Tainai, Niigata 959-2702, Japan.
| |
Collapse
|
22
|
Onodera T, Kanaya G, Hatamoto M, Kohzu A, Iguchi A, Takimoto Y, Yamaguchi T, Mizuochi M, Syutsubo K. Evaluation of trophic transfer in the microbial food web during sludge degradation based on 13C and 15N natural abundance. WATER RESEARCH 2018; 146:30-36. [PMID: 30261359 DOI: 10.1016/j.watres.2018.09.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 09/03/2018] [Accepted: 09/04/2018] [Indexed: 06/08/2023]
Abstract
Carbon and nitrogen stable isotope ratios (δ13C and δ15N) were determined in activated sludge, which was exposed to endogenous conditions for 36 days and contained a wide diversity of organisms across several trophic levels. The aim of this study was to elucidate the fluctuation of δ13C and δ15N through trophic transfer in the microbial consortia. The sludge was evaluated in view of sludge mass, bacterial community, higher trophic organisms, sludge δ13C and δ15N, and δ15N and δ18O of nitrate. The results show that the activated sludge became more enriched with 15N as degradation proceeded. Eventually, the mixed liquor volatile suspended solid concentrations in the activated sludge decreased from 1610 to 710 mg/L and the δ15N of the sludge increased from 8.3‰ to 10.8‰. In contrast, the δ13C values of the sludge were stable. Microscope observations confirmed that consumers such as Rotifera, Tardigrada and Annelida (Aelosoma sp.) were present in the activated sludge for the entire operational period. The abundance of those organisms drastically changed during the operational periods, and the diversity in bacterial community also changed, resulting in community succession. Changes in biotic community, reduction in sludge mass, and increase in δ15N of the sludge occurred during the sludge degradation processes. This implies that the sludge degradation was partly caused by the trophic conversion of the sludge-derived nitrogen in the food web. The δ15N of the sludge can be used as an indicator of the sludge degradation through trophic transfer in wastewater treatment reactors. These findings provide new insights into understanding trophic transfer during microbial community succession and the effects of the feeding process on sludge degradation.
Collapse
Affiliation(s)
- Takashi Onodera
- Center for Regional Environmental Research, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki, 305-8506, Japan.
| | - Gen Kanaya
- Center for Regional Environmental Research, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki, 305-8506, Japan.
| | - Masashi Hatamoto
- Department of Civil and Environmental Engineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, 940-2188, Japan.
| | - Ayato Kohzu
- Center for Regional Environmental Research, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki, 305-8506, Japan.
| | - Akinori Iguchi
- Faculty of Applied Life Sciences, Niigata University of Pharmacy and Applied Life Sciences, Niigata, 956-0841, Japan.
| | - Yuya Takimoto
- Department of Civil and Environmental Engineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, 940-2188, Japan.
| | - Takashi Yamaguchi
- Department of Civil and Environmental Engineering, Nagaoka University of Technology, 1603-1 Kamitomioka, Nagaoka, Niigata, 940-2188, Japan.
| | - Motoyuki Mizuochi
- Center for Regional Environmental Research, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki, 305-8506, Japan.
| | - Kazuaki Syutsubo
- Center for Regional Environmental Research, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki, 305-8506, Japan.
| |
Collapse
|
23
|
Salehiziri M, Amini Rad H, Novak JT. Disruption of cell to cell communication in the aeration unit of a cannibal process: Sludge reduction efficiency and related mechanisms. Biochem Eng J 2018. [DOI: 10.1016/j.bej.2018.06.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
|
24
|
Jabari P, Yuan Q, Oleszkiewicz JA. Overall effect of carbon production and nutrient release in sludge holding tank on mainstream biological nutrient removal efficiency. ENVIRONMENTAL TECHNOLOGY 2018; 39:2390-2410. [PMID: 28712337 DOI: 10.1080/09593330.2017.1355934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2017] [Accepted: 07/11/2017] [Indexed: 06/07/2023]
Abstract
The potential of hydrolysis/fermentation of activated sludge in sludge holding tank (SHT) to produce additional carbon for the biological nutrient removal (BNR) process was investigated. The study was conducted in anaerobic batch tests using the BNR sludge (from a full-scale Westside process) and the mixture of BNR sludge with conventional non-BNR activated sludge (to have higher biodegradable particulate chemical oxygen demand (bpCOD) in sludge). The BioWin 4.1 was used to simulate the anaerobic batch test of the BNR sludge. Also, the overall effect of FCOD production and nutrient release on BNR efficiency of the Westside process was estimated. The experimental results showed that the phosphorous uptake of sludge increased during hydrolysis/ fermentation condition up to the point when poly-P was completely utilized; afterwards, it decreased significantly. The BioWin simulation could not predict the loss of aerobic phosphorous uptake after poly-P was depleted. The results showed that in the case of activated sludge with relatively higher bpCOD (originating from plants with short sludge retention time or without primary sedimentation), beneficial effect of SHT on BNR performance is feasible. In order to increase the potential of SHT to enhance BNR efficiency, a relatively low retention time and high sludge load is recommended.
Collapse
Affiliation(s)
- Pouria Jabari
- a Department of Civil Engineering , University of Manitoba , Winnipeg , Canada
| | - Qiuyan Yuan
- a Department of Civil Engineering , University of Manitoba , Winnipeg , Canada
| | - Jan A Oleszkiewicz
- a Department of Civil Engineering , University of Manitoba , Winnipeg , Canada
| |
Collapse
|
25
|
El Moussaoui T, Jaouad Y, Mandi L, Marrot B, Ouazzani N. Biomass behaviour in a conventional activated sludge system treating olive mill wastewater. ENVIRONMENTAL TECHNOLOGY 2018; 39:190-202. [PMID: 28276836 DOI: 10.1080/09593330.2017.1296899] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 02/14/2017] [Indexed: 06/06/2023]
Abstract
The current work aims to study the biomass behaviour in a continuous mode activated sludge system (ASS) treating olive mill wastewater (OMWW) through an increasing OMWW food to microorganism ration (F/M). To this end, the biomass growth, the specific oxygen uptake rate (SOUR), microbial characterization, sludge volume index (SVI) as well as COD and phenolic compounds removal efficiencies were examined over time. Results showed a successful growth of the biomass that reached 6.79 gTSS l-1 and 5.42 gVSS l-1. Its viability, its adaptability, and its good physiological activity were confirmed by the obtained result of SOUR with an average of 9.95 mgO2 gVSS-1h-1, as well as aerobic microbial population characterization in terms of aerobic revivable bacteria at 22°C and 37°C, Pseudomonas sp., mould and yeast and total fungi. The concentration of these strains characterized by their ability to degrade effectively COD and phenolic compounds increased significantly (p < .05) over time. This demonstrated a great promptness in response to the increasing OMWW mass ratio. For all treatment steps, removal efficiencies were high and reached 95% of COD and 93% of phenolic compounds, also the flocs settleability shown by SVI measurement was optimal.
Collapse
Affiliation(s)
- Tawfik El Moussaoui
- a Laboratory of Hydrobiology Ecotoxicology and Sanitation LHEA URAC 33 , University Cadi Ayyad , Marrakech , Morocco
- b National Center for Studies and Research on Water and Energy (CNEREE), BP/511 , University Cadi Ayyad , Marrakech , Morocco
| | - Yasamine Jaouad
- a Laboratory of Hydrobiology Ecotoxicology and Sanitation LHEA URAC 33 , University Cadi Ayyad , Marrakech , Morocco
- b National Center for Studies and Research on Water and Energy (CNEREE), BP/511 , University Cadi Ayyad , Marrakech , Morocco
| | - Laila Mandi
- a Laboratory of Hydrobiology Ecotoxicology and Sanitation LHEA URAC 33 , University Cadi Ayyad , Marrakech , Morocco
- b National Center for Studies and Research on Water and Energy (CNEREE), BP/511 , University Cadi Ayyad , Marrakech , Morocco
| | - Benoît Marrot
- c Aix-Marseille Université, CNRS, Centrale Marseille , M2P2 UMR 7340, 13541 , Marseille , France
| | - Naaila Ouazzani
- a Laboratory of Hydrobiology Ecotoxicology and Sanitation LHEA URAC 33 , University Cadi Ayyad , Marrakech , Morocco
- b National Center for Studies and Research on Water and Energy (CNEREE), BP/511 , University Cadi Ayyad , Marrakech , Morocco
| |
Collapse
|
26
|
Liu Y, Li X, Zhao J, Wang D, Yang Q, Zeng G. The feasibility of enhanced biological phosphorus removal in the novel oxic/extended idle process using fermentation liquid from sludge fermentation. RSC Adv 2018; 8:3321-3327. [PMID: 35541212 PMCID: PMC9077545 DOI: 10.1039/c7ra12886j] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 01/10/2018] [Indexed: 11/28/2022] Open
Abstract
Carbon sources are essential for biological phosphorus removal (BPR); the carbon sources, however, are often inadequate in municipal wastewater treatment plants. This study demonstrated the feasibility of sludge fermentation liquid enhanced by biosurfactant alkylpolyglycosides (APG) as carbon sources to improve the performance of BPR in the novel oxic/extended idle (O/EI) reactor and the underlying mechanism was also investigated. The results showed that APG induced fermentation liquid could enhance the BPR performance in the O/EI reactor, and the BPR efficiency was 95.2%, which was significantly higher than that in the conventional anaerobic/oxic (A/O) reactor. Mechanism investigation showed that compared with the A/O reactor, the O/EI reactor enriched more polyphosphate accumulating organisms (PAOs) (38.2%), but less glycogen accumulating organisms (GAOs) when the APG-induced fermentation liquid was used as carbon source. The transformations of the polyhydroxyalkanoates (PHA) and glycogen in the O/EI reactor were lower than those in the A/O reactor. Further study found that the activities of polyphosphate kinase (PPK) and acetyl-CoA synthases (ACS) in the O/EI reactor were significantly higher than those of the A/O reactor, which was consistent with the higher BPR efficiency in the O/EI reactor. Long-term effect of fermented liquid as carbon source on effluent COD and SOP in O/EI reactor.![]()
Collapse
Affiliation(s)
- Yang Liu
- College of Environmental Science and Engineering
- Hunan University
- Changsha 410082
- P. R. China
- Key Laboratory of Environmental Biology and Pollution Control
| | - Xiaoming Li
- College of Environmental Science and Engineering
- Hunan University
- Changsha 410082
- P. R. China
- Key Laboratory of Environmental Biology and Pollution Control
| | - Jianwei Zhao
- College of Environmental Science and Engineering
- Hunan University
- Changsha 410082
- P. R. China
- Key Laboratory of Environmental Biology and Pollution Control
| | - Dongbo Wang
- College of Environmental Science and Engineering
- Hunan University
- Changsha 410082
- P. R. China
- Key Laboratory of Environmental Biology and Pollution Control
| | - Qi Yang
- College of Environmental Science and Engineering
- Hunan University
- Changsha 410082
- P. R. China
- Key Laboratory of Environmental Biology and Pollution Control
| | - Guangming Zeng
- College of Environmental Science and Engineering
- Hunan University
- Changsha 410082
- P. R. China
- Key Laboratory of Environmental Biology and Pollution Control
| |
Collapse
|
27
|
Li ZH, Ma ZB, Yu HQ. Respiration adaptation of activated sludge under dissolved oxygen and hypochlorite stressed conditions. BIORESOURCE TECHNOLOGY 2018; 248:171-178. [PMID: 28736142 DOI: 10.1016/j.biortech.2017.06.166] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2017] [Revised: 06/28/2017] [Accepted: 06/29/2017] [Indexed: 06/07/2023]
Abstract
In this work, the relationship between environmental disturbance and the recovery of activated sludge at a low dissolved oxygen of 0.5mg/l or in the presence of sodium hypochlorite of 1-15mg Cl2/gSS/d was examined. When microorganisms entered their physiological adaptation period, a sharp increase in endogenous respiration rate was observed. The activity recovery potential of sludge depended on the ratio of the endogenous respiration rate to the maximum respiration rate. A subsequent decrease in this ratio after a sharp increase indicates that the disturbance was recoverable. An increase in this ratio to a certain value, e.g., 0.35, suggests that the sludge system could not adapt to the new environments and thus was unrecoverable. In addition, the recoveries of sludge respiration and effluent quality were asynchronous, which was impacted by both sludge activity and operating conditions. These results provide a useful approach for the operation of activated sludge systems.
Collapse
Affiliation(s)
- Zhi-Hua Li
- Key Laboratory of Northwest Water Resource, Environment and Ecology, Ministry of Education, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Zhi-Bo Ma
- Key Laboratory of Northwest Water Resource, Environment and Ecology, Ministry of Education, School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Han-Qing Yu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science & Technology of China, Hefei 230026, China.
| |
Collapse
|
28
|
Liu W, Peng Y, Ma B, Ma L, Jia F, Li X. Dynamics of microbial activities and community structures in activated sludge under aerobic starvation. BIORESOURCE TECHNOLOGY 2017; 244:588-596. [PMID: 28803110 DOI: 10.1016/j.biortech.2017.07.131] [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: 06/21/2017] [Revised: 07/21/2017] [Accepted: 07/23/2017] [Indexed: 06/07/2023]
Abstract
The knowledge of the effect of aerobic starvation on the functional bacterial activities and community structures is important for the recovery of nutrient removal in activated sludge system. Four aerobic starvation processes (3, 7, 14 and 30days) for nitrifiers and polyphosphate accumulating organisms (PAOs) were studied. The results showed that nitrifiers could utilize the released ammonium for growth during the first 7days of the aerobic starvation, and then gradually decayed. In the recovery period, the slower recovery ability of nitrite-oxidizing bacteria (NOB) than ammonium-oxidizing bacteria (AOB) contributed to the nitrite accumulation. Besides, the sequential consumption of polyhydroxyalkanoates (PHA), glycogen and the utilization of polyphosphate (poly-P) in PAOs provided the energy to maintain bacterial metabolic activity. High-throughput sequencing analysis revealed that aerobic starvation had substantial impacts on the succession of microbial community, and the majority of original dominant species within the phylum Proteobacteria and Bacteroidetes declined while Firmicutes increased.
Collapse
Affiliation(s)
- Wenlong Liu
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Yongzhen Peng
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China; Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China.
| | - Bin Ma
- Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China
| | - Linna Ma
- Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China
| | - Fangxu Jia
- Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China
| | - Xiyao Li
- Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China
| |
Collapse
|
29
|
Maqbool T, Cho J, Hur J. Dynamic changes of dissolved organic matter in membrane bioreactors at different organic loading rates: Evidence from spectroscopic and chromatographic methods. BIORESOURCE TECHNOLOGY 2017; 234:131-139. [PMID: 28319761 DOI: 10.1016/j.biortech.2017.03.035] [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: 01/27/2017] [Revised: 02/26/2017] [Accepted: 03/05/2017] [Indexed: 06/06/2023]
Abstract
Excitation emission matrix-parallel factor analysis (EEM-PARAFAC) and size exclusion chromatography (SEC) were utilized to explore the dynamics in extracellular polymeric substances (EPS), soluble microbial products (SMP), and effluent for the membrane bioreactors at two different organic loading rates (OLRs). Combination of three different fluorescent components explained the compositional changes of dissolved organic matter. The lower OLR resulted in a higher production of tryptophan-like component (C1) in EPS, while the opposite trends were found for the other two components (humic-like C2 and tyrosine-like C3), signifying the role of C1 in the endogenous condition. Larger sized molecules were more greatly produced in EPS at the lower OLR. Meanwhile, all the size fractions of SMP were more abundant at the higher OLR particular for the early phase of the operation. Irrespective of the OLR, the higher degrees of the membrane retention were found for relatively large sized and protein-like molecules.
Collapse
Affiliation(s)
- Tahir Maqbool
- Department of Environment and Energy, Sejong University, Seoul 05006, South Korea
| | - Jinwoo Cho
- Department of Environment and Energy, Sejong University, Seoul 05006, South Korea
| | - Jin Hur
- Department of Environment and Energy, Sejong University, Seoul 05006, South Korea.
| |
Collapse
|
30
|
Zafiriadis I, Kapagiannidis AG, Ntougias S, Aivasidis A. Inhibition of the respiratory chain reactions in denitrifying EBPR biomass under simultaneous presence of acetate and electron acceptor. N Biotechnol 2017; 36:42-50. [DOI: 10.1016/j.nbt.2017.01.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 12/15/2016] [Accepted: 01/20/2017] [Indexed: 10/20/2022]
|
31
|
Shen N, Chen Y, Zhou Y. Multi-cycle operation of enhanced biological phosphorus removal (EBPR) with different carbon sources under high temperature. WATER RESEARCH 2017; 114:308-315. [PMID: 28259067 DOI: 10.1016/j.watres.2017.02.051] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Revised: 12/08/2016] [Accepted: 02/21/2017] [Indexed: 05/25/2023]
Abstract
Many studies reported that it is challenging to apply enhanced biological phosphorus removal (EBPR) process at high temperature. Glycogen accumulating organisms (GAOs) could easily gain their dominance over poly-phosphate accumulating organisms (PAOs) when the operating temperature was in the range of 25 °C-30 °C. However, a few successful EBPR processes operated at high temperature have been reported recently. This study aimed to have an in-depth understanding on the impact of feeding strategy and carbon source types on EBPR performance in tropical climate. P-removal performance of two EBPR systems was monitored through tracking effluent quality and cyclic studies. The results confirmed that EBPR was successfully obtained and maintained at high temperature with a multi-cycle strategy. More stable performance was observed with acetate as the sole carbon source compared to propionate. Stoichiometric ratios of phosphorus and carbon transformation during both anaerobic and aerobic phases were higher at high temperature than low temperature (20±1 °C) except anaerobic PHA/C ratios within most of the sub-cycles. Furthermore, the fractions of PHA and glycogen in biomass were lower compared with one-cycle pulse feed operation. The microbial community structure was more stable in acetate-fed sequencing batch reactor (C2-SBR) than that in propionate-fed reactor (C3-SBR). Accumulibacter Clade IIC was found to be highly abundant in both reactors.
Collapse
Affiliation(s)
- Nan Shen
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, 637141, Singapore; School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore
| | - Yun Chen
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, 637141, Singapore
| | - Yan Zhou
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, 637141, Singapore; School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore.
| |
Collapse
|
32
|
Wang Y, Zhou S, Wang H, Ye L, Qin J, Lin X. Comparison of endogenous metabolism during long-term anaerobic starvation of nitrite/nitrate cultivated denitrifying phosphorus removal sludges. WATER RESEARCH 2015; 68:374-386. [PMID: 25462744 DOI: 10.1016/j.watres.2014.09.044] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Revised: 09/26/2014] [Accepted: 09/28/2014] [Indexed: 06/04/2023]
Abstract
Denitrifying phosphorus removal (DPR) by denitrifying phosphorus-accumulating organisms (DPAOs) is a promising approach for reducing energy and carbon usage. However, influent fluctuations or interruptions frequently expose the DPAOs biomass to starvation conditions, reducing biomass activity and amount, and ultimately degrading the performance of DPR. Therefore, a better understanding of the endogenous metabolism and recovery ability of DPAOs is urgently required. In the present study, anaerobic starvation (12 days) and recovery were investigated in nitrite- and nitrate-cultivated DPAOs at 20 ± 1 °C. The cell decay rates in nitrite-DPAOs sludges from the end of the anaerobic and aerobic phase were 0.008 day⁻¹ and 0.007 day⁻¹, respectively, being 64% and 68% lower than those of nitrate-DPAOs sludges. Nitrite-DPAOs sludges also recovered more rapidly than nitrate-DPAOs sludge after 12 days of starvation. The maintenance energy of nitrite-DPAOs sludges from the end of the anaerobic and aerobic phase were approximately 31% and 34% lower, respectively, than those of nitrate-DPAOs sludges. Glycogen and polyphosphate (poly-P) sequentially served as the main maintenance energy sources in both nitrite-and nitrate-DPAOs sludges. However, the transformation pathway of the intracellular polymers during starvation differed between them. Nitrate-DPAOs sludge used extracellular polymeric substances (EPS) (mainly polysaccharides) as an additional maintenance energy source during the first 3 days of starvation. During this phase, EPS appeared to contribute to 19-27% of the ATP production in nitrate-DPAOs, but considerably less to the cell maintenance of nitrite-DPAOs. The high resistance of nitrite-DPAOs to starvation might be attributable to frequent short-term starvation and exposure to toxic substances such as nitrite/free nitrous acids in the parent nitrite-fed reactor. The strong resistance of nitrite-DPAOs sludge to anaerobic starvation may be exploited in P removal by shortcut denitrification processes.
Collapse
Affiliation(s)
- Yayi Wang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, PR China.
| | | | | | | | | | | |
Collapse
|
33
|
Impact of salinity on the aerobic metabolism of phosphate-accumulating organisms. Appl Microbiol Biotechnol 2014; 99:3659-72. [DOI: 10.1007/s00253-014-6287-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Revised: 11/27/2014] [Accepted: 11/29/2014] [Indexed: 11/25/2022]
|
34
|
Carvalheira M, Oehmen A, Carvalho G, Eusébio M, Reis MAM. The impact of aeration on the competition between polyphosphate accumulating organisms and glycogen accumulating organisms. WATER RESEARCH 2014; 66:296-307. [PMID: 25222333 DOI: 10.1016/j.watres.2014.08.033] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Revised: 08/01/2014] [Accepted: 08/23/2014] [Indexed: 05/08/2023]
Abstract
In wastewater treatment plants (WWTPs), aeration is the major energetic cost, thus its minimisation will improve the cost-effectiveness of the process. This study shows that both the dissolved oxygen (DO) concentration and aerobic hydraulic retention time (HRT) affect the competition between polyphosphate accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs). At low DO levels, Accumulibacter PAOs were shown to have an advantage over Competibacter GAOs, as PAOs had a higher oxygen affinity and thus largely maintained their aerobic activity at low DO levels, while GAO activity decreased. Bioreactor operation at low DO levels was found to increase the PAO fraction of the sludge. Furthermore, an increase in aerobic HRT (at a DO level of 2 mg O2/L), promoted the proliferation of GAOs over PAOs, decreasing the EBPR efficiency. Overall, this study shows that low aeration can be beneficial for EBPR performance through selecting for PAOs over GAOs, which should be incorporated into WWTP models in order to minimise energetic costs and improve WWTP sustainability.
Collapse
Affiliation(s)
- Mónica Carvalheira
- Requimte/CQFB, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus de Caparica, 2829-516 Caparica, Portugal.
| | - Adrian Oehmen
- Requimte/CQFB, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus de Caparica, 2829-516 Caparica, Portugal.
| | - Gilda Carvalho
- Requimte/CQFB, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus de Caparica, 2829-516 Caparica, Portugal; Instituto de Biologia Experimental e Tecnológica (IBET), Av. da República (EAN), 2784-505 Oeiras, Portugal.
| | - Mário Eusébio
- Requimte/CQFB, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus de Caparica, 2829-516 Caparica, Portugal.
| | - Maria A M Reis
- Requimte/CQFB, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus de Caparica, 2829-516 Caparica, Portugal.
| |
Collapse
|
35
|
Lanham AB, Oehmen A, Saunders AM, Carvalho G, Nielsen PH, Reis MAM. Metabolic modelling of full-scale enhanced biological phosphorus removal sludge. WATER RESEARCH 2014; 66:283-295. [PMID: 25222332 DOI: 10.1016/j.watres.2014.08.036] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Revised: 08/01/2014] [Accepted: 08/23/2014] [Indexed: 06/03/2023]
Abstract
This study investigates, for the first time, the application of metabolic models incorporating polyphosphate accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs) towards describing the biochemical transformations of full-scale enhanced biological phosphorus removal (EBPR) activated sludge from wastewater treatment plants (WWTPs). For this purpose, it was required to modify previous metabolic models applied to lab-scale systems by incorporating the anaerobic utilisation of the TCA cycle and the aerobic maintenance processes based on sequential utilisation of polyhydroxyalkanoates, followed by glycogen and polyphosphate. The abundance of the PAO and GAO populations quantified by fluorescence in situ hybridisation served as the initial conditions of each biomass fraction, whereby the models were able to describe accurately the experimental data. The kinetic rates were found to change among the four different WWTPs studied or even in the same plant during different seasons, either suggesting the presence of additional PAO or GAO organisms, or varying microbial activities for the same organisms. Nevertheless, these variations in kinetic rates were largely found to be proportional to the difference in acetate uptake rate, suggesting a viable means of calibrating the metabolic model. The application of the metabolic model to full-scale sludge also revealed that different Accumulibacter clades likely possess different acetate uptake mechanisms, as a correlation was observed between the energetic requirement for acetate transport across the cell membrane with the diversity of Accumulibacter present. Using the model as a predictive tool, it was shown that lower acetate concentrations in the feed as well as longer aerobic retention times favour the dominance of the TCA metabolism over glycolysis, which could explain why the anaerobic TCA pathway seems to be more relevant in full-scale WWTPs than in lab-scale systems.
Collapse
Affiliation(s)
- Ana B Lanham
- REQUIMTE/CQFB, Chemistry Department FCT-UNL, 2829-516 Caparica, Portugal.
| | - Adrian Oehmen
- REQUIMTE/CQFB, Chemistry Department FCT-UNL, 2829-516 Caparica, Portugal.
| | - Aaron M Saunders
- Center for Microbial Communities, Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Denmark.
| | - Gilda Carvalho
- REQUIMTE/CQFB, Chemistry Department FCT-UNL, 2829-516 Caparica, Portugal; Instituto de Biologia Experimental e Tecnológica, Apt.12, 2781-901 Oeiras, Portugal.
| | - Per H Nielsen
- Center for Microbial Communities, Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Denmark.
| | - Maria A M Reis
- REQUIMTE/CQFB, Chemistry Department FCT-UNL, 2829-516 Caparica, Portugal.
| |
Collapse
|
36
|
Fall C, Rogel-Dorantes JA, Millán-Lagunas EL, Martínez-García CG, Silva-Hernández BC, Silva-Trejo FS. Modeling and parameter estimation of two-phase endogenous respirograms and COD measurements during aerobic digestion of biological sludge. BIORESOURCE TECHNOLOGY 2014; 173:291-300. [PMID: 25310865 DOI: 10.1016/j.biortech.2014.09.120] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2014] [Revised: 09/21/2014] [Accepted: 09/23/2014] [Indexed: 06/04/2023]
Abstract
Long-term aerobic digestion batch tests were performed on a sludge that contained mainly two fractions, a heterotrophic biomass XH and its endogenous residues XP, which were cultivated in conditions known to favor bio-storage (XSto). The objective was to model the stabilization of the sludge and determine the parameters of the endogenous decay processes, based on simultaneous measurements of the chemical oxygen demand (COD) and oxygen uptake rates (OUR). The respirograms were shown to have a two-phase structure that was describable with activated sludge model 3 (ASM3), but not with ASM1. Comparing the information from the COD and OUR data suggested the presence of two different groups of heterotrophs (XHa and XHb), one that decays with oxygen consumption and another without using O2. A modified ASM3 model was proposed, which was able to fit the OUR and COD data from the digesters, as well as cases from the literature.
Collapse
Affiliation(s)
- C Fall
- Centro Interamericano de Recursos del Agua (CIRA), Universidad Autónoma del Estado de México (UAEM), Apdo postal 367, Toluca C.P. 50091, Mexico.
| | - J A Rogel-Dorantes
- Centro Interamericano de Recursos del Agua (CIRA), Universidad Autónoma del Estado de México (UAEM), Apdo postal 367, Toluca C.P. 50091, Mexico
| | - E L Millán-Lagunas
- Centro Interamericano de Recursos del Agua (CIRA), Universidad Autónoma del Estado de México (UAEM), Apdo postal 367, Toluca C.P. 50091, Mexico
| | - C G Martínez-García
- Centro Interamericano de Recursos del Agua (CIRA), Universidad Autónoma del Estado de México (UAEM), Apdo postal 367, Toluca C.P. 50091, Mexico
| | - B C Silva-Hernández
- Centro Interamericano de Recursos del Agua (CIRA), Universidad Autónoma del Estado de México (UAEM), Apdo postal 367, Toluca C.P. 50091, Mexico
| | - F S Silva-Trejo
- Centro Interamericano de Recursos del Agua (CIRA), Universidad Autónoma del Estado de México (UAEM), Apdo postal 367, Toluca C.P. 50091, Mexico
| |
Collapse
|
37
|
Carvalheira M, Oehmen A, Carvalho G, Reis MAM. Survival strategies of polyphosphate accumulating organisms and glycogen accumulating organisms under conditions of low organic loading. BIORESOURCE TECHNOLOGY 2014; 172:290-296. [PMID: 25270044 DOI: 10.1016/j.biortech.2014.09.059] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 09/09/2014] [Accepted: 09/13/2014] [Indexed: 06/03/2023]
Abstract
Enhanced biological phosphorus removal (EBPR) is usually limited by organic carbon availability in wastewater treatment plants (WWTPs). Polyphosphate accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs) were operated under extended periods with low organic carbon loading in order to examine its impact on their activity and survival. The decrease in organic carbon load affected PAOs and GAOs in different ways, where the biomass decay rate of GAOs was approximately 4times higher than PAOs. PAOs tended to conserve a relatively high residual concentration of polyhydroxyalkanoates (PHAs) under aerobic conditions, while GAOs tended to deplete their available PHA more rapidly. This slower oxidation rate of PHA by PAOs at residual concentration levels enabled them to maintain an energy source for aerobic maintenance processes for longer than GAOs. This may provide PAOs with an advantage over GAOs in surviving the low organic loading conditions commonly found in full-scale wastewater treatment plants.
Collapse
Affiliation(s)
- Mónica Carvalheira
- Requimte/CQFB, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus de Caparica, 2829-516 Caparica, Portugal
| | - Adrian Oehmen
- Requimte/CQFB, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus de Caparica, 2829-516 Caparica, Portugal
| | - Gilda Carvalho
- Requimte/CQFB, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus de Caparica, 2829-516 Caparica, Portugal; Instituto de Biologia Experimental e Tecnológica (IBET), Av. da República (EAN), 2784-505 Oeiras, Portugal
| | - Maria A M Reis
- Requimte/CQFB, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Campus de Caparica, 2829-516 Caparica, Portugal.
| |
Collapse
|
38
|
Martínez-García CG, Olguín MT, Fall C. Aerobic stabilization of biological sludge characterized by an extremely low decay rate: modeling, identifiability analysis and parameter estimation. BIORESOURCE TECHNOLOGY 2014; 166:112-119. [PMID: 24907570 DOI: 10.1016/j.biortech.2014.05.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2014] [Revised: 05/09/2014] [Accepted: 05/11/2014] [Indexed: 06/03/2023]
Abstract
Aerobic digestion batch tests were run on a sludge model that contained only two fractions, the heterotrophic biomass (XH) and its endogenous residue (XP). The objective was to describe the stabilization of the sludge and estimate the endogenous decay parameters. Modeling was performed with Aquasim, based on long-term data of volatile suspended solids and chemical oxygen demand (VSS, COD). Sensitivity analyses were carried out to determine the conditions for unique identifiability of the parameters. Importantly, it was found that the COD/VSS ratio of the endogenous residues (1.06) was significantly lower than for the active biomass fraction (1.48). The decay rate constant of the studied sludge (low bH, 0.025 d(-1)) was one-tenth that usually observed (0.2d(-1)), which has two main practical significances. Digestion time required is much more long; also the oxygen uptake rate might be <1.5 mg O₂/gTSSh (biosolids standards), without there being significant decline in the biomass.
Collapse
Affiliation(s)
- C G Martínez-García
- Centro Interamericano de Recursos del Agua (CIRA), Universidad Autónoma del Estado de México (UAEM), Apdo Postal 367, Toluca C.P. 50091, Mexico
| | - M T Olguín
- Departamento de Química, Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, Col. Escandón, Del. Miguel Hidalgo, C.P. 11801 Mexico, DF, Mexico
| | - C Fall
- Centro Interamericano de Recursos del Agua (CIRA), Universidad Autónoma del Estado de México (UAEM), Apdo Postal 367, Toluca C.P. 50091, Mexico.
| |
Collapse
|
39
|
Moreno-Andrade I, Kumar G, Buitrón G. Effect of Starvation upon Activity of Microorganisms Degrading 4-Chlorophenol. J CHIN CHEM SOC-TAIP 2014. [DOI: 10.1002/jccs.201300647] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
40
|
Özdemir S, Çokgör EU, Orhon D. Modeling the fate of particulate components in aerobic sludge stabilization--performance limitations. BIORESOURCE TECHNOLOGY 2014; 164:315-322. [PMID: 24865324 DOI: 10.1016/j.biortech.2014.05.012] [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: 03/06/2014] [Revised: 05/02/2014] [Accepted: 05/03/2014] [Indexed: 06/03/2023]
Abstract
The study investigated the effect of sludge composition on the limitations of aerobic stabilization. It was designed with the foresight that the stabilization mechanism could only be elucidated if the observed volatile suspended solids reduction were correlated with the fate of particulate components in sludge. Biomass sustained at sludge ages of 2 and 10 days were used in the stabilization reactors. Particulate components were determined by model evaluation of corresponding oxygen uptake rate profiles. Interpretation of the experimental data by modeling, based on death-regeneration mechanism without external substrate, could simulate the fate and evolution of major components in sludge during stabilization. It showed that both microbial decay and hydrolysis of non viable cellular material proceeded at much slower rates as compared with biological systems sustained with substrate feeding. Modeling also indicated that particulate metabolic products generated by sludge acclimated to high sludge age undergo slow biodegradation under prolonged stabilization.
Collapse
Affiliation(s)
- S Özdemir
- Faculty of Civil Engineering, Environmental Engineering Department, Istanbul Technical University, 34469 Maslak, Istanbul, Turkey; Istanbul Metropolitan Municipality, Directorate of Environmental Protection, 34169 Gungoren, Istanbul, Turkey.
| | - E U Çokgör
- Faculty of Civil Engineering, Environmental Engineering Department, Istanbul Technical University, 34469 Maslak, Istanbul, Turkey
| | - D Orhon
- Faculty of Civil Engineering, Environmental Engineering Department, Istanbul Technical University, 34469 Maslak, Istanbul, Turkey; Envis Energy and Environmental Systems Research Development Ltd., İ.T.Ü. Arı Teknokent, Arı 1 Building, No. 16, 34469 Maslak, Istanbul, Turkey
| |
Collapse
|
41
|
Welles L, Lopez-Vazquez CM, Hooijmans CM, van Loosdrecht MCM, Brdjanovic D. Impact of salinity on the anaerobic metabolism of phosphate-accumulating organisms (PAO) and glycogen-accumulating organisms (GAO). Appl Microbiol Biotechnol 2014; 98:7609-22. [DOI: 10.1007/s00253-014-5778-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Revised: 04/12/2014] [Accepted: 04/16/2014] [Indexed: 10/25/2022]
|
42
|
Wei J, Imai T, Higuchi T, Arfarita N, Yamamoto K, Sekine M, Kanno A. Effect of different carbon sources on the biological phosphorus removal by a sequencing batch reactor using pressurized pure oxygen. BIOTECHNOL BIOTEC EQ 2014; 28:471-477. [PMID: 26019532 PMCID: PMC4434035 DOI: 10.1080/13102818.2014.924200] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2012] [Accepted: 01/29/2014] [Indexed: 11/05/2022] Open
Abstract
The effect of different carbon source on the efficiency of enhanced biological phosphorus removal (EBPR) from synthetic wastewater with acetate and two ratios of acetate/starch as a carbon source was investigated. Three pressurized pure oxygen sequencing batch reactor (POSBR) experiments were operated. The reactors (POSBR1, POSBR2 and POSBR3) were developed and studied at different carbon source ratios of 100% acetate, 75% acetate plus 25% starch and 50% acetate plus 50% starch, respectively. The results showed that POSBR1 had a higher phosphate release-to-uptake ratio and, respectively, in a much higher phosphorus removal efficiency (93.8%) than POSBR2 (84.7%) and POSBR3 (77.3%) within 30 days of operation. This indicated that the phosphorus removal efficiency decreased the higher the starch concentration was. It was also found that POSBR1 produced more polyhydroxyalkanoates (PHAs) than the other reactors. Based on the effect of the carbon source on the PHA concentration and consumption, the conditions of POSBR1 were favourable for the growth of polyphosphate-accumulating organisms and therefore, beneficial for the biological phosphorus removal process.
Collapse
Affiliation(s)
- Jie Wei
- Graduate School of Science and Engineering, Division of Environmental Science and Engineering, Yamaguchi University, Yamaguchi, Japan
| | - Tsuyoshi Imai
- Graduate School of Science and Engineering, Division of Environmental Science and Engineering, Yamaguchi University, Yamaguchi, Japan
| | - Takaya Higuchi
- Graduate School of Science and Engineering, Division of Environmental Science and Engineering, Yamaguchi University, Yamaguchi, Japan
| | - Novi Arfarita
- Graduate School of Science and Engineering, Division of Environmental Science and Engineering, Yamaguchi University, Yamaguchi, Japan
- Faculty of Agrotechnology, Malang Islamic University, Malang, Indonesia
| | - Koichi Yamamoto
- Systems Design and Engineering, Graduate School of Science and Engineering, Yamaguchi University, Yamaguchi, Japan
| | - Masahiko Sekine
- Systems Design and Engineering, Graduate School of Science and Engineering, Yamaguchi University, Yamaguchi, Japan
| | - Ariyo Kanno
- Systems Design and Engineering, Graduate School of Science and Engineering, Yamaguchi University, Yamaguchi, Japan
| |
Collapse
|
43
|
Dynamics of intracellular polymers in enhanced biological phosphorus removal processes under different organic carbon concentrations. BIOMED RESEARCH INTERNATIONAL 2014; 2013:761082. [PMID: 24381942 PMCID: PMC3867947 DOI: 10.1155/2013/761082] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Accepted: 11/16/2013] [Indexed: 11/23/2022]
Abstract
Enhanced biological phosphorus removal (EBPR) may deteriorate or fail during low organic carbon loading periods. Polyphosphate accumulating organisms (PAOs) in EBPR were acclimated under both high and low organic carbon conditions, and then dynamics of polymers in typical cycles, anaerobic conditions with excess organic carbons, and endogenous respiration conditions were examined. After long-term acclimation, it was found that organic loading rates did not affect the yield of PAOs and the applied low organic carbon concentrations were advantageous for the enrichment of PAOs. A low influent organic carbon concentration induced a high production of extracellular carbohydrate. During both anaerobic and aerobic endogenous respirations, when glycogen decreased to around 80 ± 10 mg C per gram of volatile suspended solids, PAOs began to utilize polyphosphate significantly. Regressed by the first-order reaction model, glycogen possessed the highest degradation rate and then was followed by polyphosphate, while biomass decay had the lowest degradation rate.
Collapse
|
44
|
Lanham AB, Oehmen A, Saunders AM, Carvalho G, Nielsen PH, Reis MAM. Metabolic versatility in full-scale wastewater treatment plants performing enhanced biological phosphorus removal. WATER RESEARCH 2013; 47:7032-7041. [PMID: 24210547 DOI: 10.1016/j.watres.2013.08.042] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Revised: 07/25/2013] [Accepted: 08/27/2013] [Indexed: 06/02/2023]
Abstract
This study analysed the enhanced biological phosphorus removal (EBPR) microbial community and metabolic performance of five full-scale EBPR systems by using fluorescence in situ hybridisation combined with off-line batch tests fed with acetate under anaerobic-aerobic conditions. The phosphorus accumulating organisms (PAOs) in all systems were stable and showed little variability between each plant, while glycogen accumulating organisms (GAOs) were present in two of the plants. The metabolic activity of each sludge showed the frequent involvement of the anaerobic tricarboxylic acid cycle (TCA) in PAO metabolism for the anaerobic generation of reducing equivalents, in addition to the more frequently reported glycolysis pathway. Metabolic variability in the use of the two pathways was also observed, between different systems and in the same system over time. The metabolic dynamics was linked to the availability of glycogen, where a higher utilisation of the glycolysis pathway was observed in the two systems employing side-stream hydrolysis, and the TCA cycle was more active in the A(2)O systems. Full-scale plants that showed higher glycolysis activity also exhibited superior P removal performance, suggesting that promotion of the glycolysis pathway over the TCA cycle could be beneficial towards the optimisation of EBPR systems.
Collapse
Affiliation(s)
- Ana B Lanham
- REQUIMTE/CQFB, Chemistry Department FCT-UNL, 2829-516 Caparica, Portugal.
| | | | | | | | | | | |
Collapse
|
45
|
Zheng M, Liu YC, Wang CW, Xu KN. Study on enhanced denitrification using particulate organic matter in membrane bioreactor by mechanism modeling. CHEMOSPHERE 2013; 93:2669-2674. [PMID: 24034894 DOI: 10.1016/j.chemosphere.2013.08.045] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Revised: 08/08/2013] [Accepted: 08/10/2013] [Indexed: 06/02/2023]
Abstract
Particulate organic matter (POM) in wastewater is a potential denitrification carbon source, while the optimal operational mode using denitrification mechanism with POM is still unclear in wastewater treatment plants. In this work, we investigated the denitrification rates (DNRs) in a full-scale membrane bioreactor (MBR) coupled with two-stage pre-anoxic (pre-AN), and then evaluated the POM denitrification efficiency using mechanism modeling. The results indicate that POM related fraction accounted for the majority of the obtained specific DNR of 1.39±0.46mgNg(-1) MLVSS h(-1) in the second pre-AN without available soluble carbon source. The modeling approaches with calibration and validation procedures estimated a high residual POM concentration of 0.17g COD g(-1) MLVSS in the activated sludge, which provided specific DNR of 1.14mgNg(-1) MLVSS h(-1). High POM retention time in the reactor was the result of high solid retention time used in the MBR. In particular, post-AN of high biomass concentration could provide the highest POM denitrification efficiency in MBR. The MBR process combined with additional sludge reduction technology could further enhance denitrification by POM.
Collapse
Affiliation(s)
- Min Zheng
- School of Environment, Tsinghua University, Beijing 100084, China
| | | | | | | |
Collapse
|
46
|
A Novel Approach for Phosphorus Recovery and No Wasted Sludge in Enhanced Biological Phosphorus Removal Process with External COD Addition. Appl Biochem Biotechnol 2013; 172:820-8. [DOI: 10.1007/s12010-013-0575-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2013] [Accepted: 10/01/2013] [Indexed: 10/26/2022]
|
47
|
Wang Y, Guo G, Wang H, Stephenson T, Guo J, Ye L. Long-term impact of anaerobic reaction time on the performance and granular characteristics of granular denitrifying biological phosphorus removal systems. WATER RESEARCH 2013; 47:5326-37. [PMID: 23863379 DOI: 10.1016/j.watres.2013.06.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Revised: 05/30/2013] [Accepted: 06/06/2013] [Indexed: 05/12/2023]
Abstract
Removal of nitrogen and phosphorus (P) from wastewater is successfully and widely practiced in systems employing both granular sludge technology and enhanced biological P removal (EBPR) processes; however, the key parameter, anaerobic reaction time (AnRT), has not been thoroughly investigated. Successful EBPR is highly dependent on an appropriate AnRT, which induces carbon and polyphosphate metabolism by phosphorus accumulating organisms (PAOs). Therefore, the long-term impact of AnRT on denitrifying P removal performance and granular characteristics was investigated in three identical granular sludge sequencing batch reactors with AnRTs of 90 (R1), 120 (R2) and 150 min (R3). The microbial community structures and anaerobic stoichiometric parameters related to various AnRTs were monitored over time. Free nitrite acid (FNA) accumulation (e.g., 0.0008-0.0016 mg HNO2-N/L) occurred frequently owing to incomplete denitrification in the adaptation period, especially in R3, which influenced the anaerobic/anoxic intracellular intermediate metabolites and activities of intracellular enzymes negatively, resulting in lower levels of poly-P and reduced activity of polyphosphate kinase. As a result, the Accumulibacter-PAOs population decreased from 51 ± 2.5% to 43 ± 2.1% when AnRT was extended from 90 to 150 min, leading to decreased denitrifying P removal performance. Additionally, frequent exposure of microorganisms to the FNA accumulation and anaerobic endogenous conditions in excess AnRT cases (e.g., 150 min) stimulated increased extracellular polymeric substances (EPS) production by microorganisms, resulting in enhanced granular formation and larger granules (size of 0.6-1.2 mm), but decreasing anaerobic PHA synthesis and glycogen hydrolysis. Phosphorus removal capacity was mediated to some extent by EPS adsorption in granular sludge systems that possessed more EPS, longer AnRT and relatively higher GAOs.
Collapse
Affiliation(s)
- Yayi Wang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, PR China.
| | | | | | | | | | | |
Collapse
|
48
|
Xu D, Chen H, Li X, Yang Q, Zeng T, Luo K, Zeng G. Enhanced biological nutrient removal in sequencing batch reactors operated as static/oxic/anoxic (SOA) process. BIORESOURCE TECHNOLOGY 2013; 143:204-211. [PMID: 23796605 DOI: 10.1016/j.biortech.2013.05.092] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2013] [Revised: 05/22/2013] [Accepted: 05/23/2013] [Indexed: 06/02/2023]
Abstract
An innovative static/oxic/anoxic (SOA) activated sludge process characterized by static phase as a substitute for conventional anaerobic stage was developed to enhance biological nutrient removal (BNR) with influent ammonia of 20 and 40 mg/L in R1 and R2 reactors, respectively. The results demonstrated that static phase could function as conventional anaerobic stage. In R1 lower influent ammonia concentration facilitated more polyphosphate accumulating organisms (PAOs) growth, but secondary phosphorus release occurred due to NOx(-) depletion during post-anoxic period. In R2, however, denitrifying phosphorus removal proceeded with sufficient NOx(-). Both R1 and R2 saw simultaneous nitrification-denitrification. Glycogen was utilized to drive post-denitrification with denitrification rates in excess of typical endogenous decay rates. The anoxic stirring duration could be shortened from 3 to 1.5h to avoid secondary phosphorus release in R1 and little adverse impact was found on nutrients removal in R2.
Collapse
Affiliation(s)
- Dechao Xu
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, China
| | | | | | | | | | | | | |
Collapse
|
49
|
Shariati FP, Heran M, Sarrafzadeh MH, Mehrnia MR, Sarzana G, Ghommidh C, Grasmick A. Biomass characterization by dielectric monitoring of viability and oxygen uptake rate measurements in a novel membrane bioreactor. BIORESOURCE TECHNOLOGY 2013; 140:357-362. [PMID: 23708851 DOI: 10.1016/j.biortech.2013.04.099] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Revised: 04/25/2013] [Accepted: 04/25/2013] [Indexed: 06/02/2023]
Abstract
The application of permittivity and oxygen uptake rate (OUR) as biological process control parameters in a wastewater treatment system was evaluated. Experiments were carried out in a novel airlift oxidation ditch membrane bioreactor under different organic loading rates (OLR). Permittivity as representative of activated sludge viability was measured by a capacitive on-line sensor. OUR was also measured as a representative for respirometric activity. Results showed that the biomass concentration increases with OLR and all biomass related measurements and simulators such as MLSS, permittivity, OUR, ASM1 and ASM3 almost follow the same increasing trends. The viability of biomass decreased when the OLR was reduced from 5 to 4 kg COD m(-3)d(-1). During decreasing of OLR, biomass related parameters generally decreased but not in a similar manner. Also, protein concentration in the system during OLR decreasing changed inversely with the activated sludge viability.
Collapse
Affiliation(s)
- Farshid Pajoum Shariati
- School of Chemical Engineering, College of Engineering, University of Tehran, Tehran, Iran; IEM, Université Montpellier 2, F-34095 Montpellier, France
| | | | | | | | | | | | | |
Collapse
|
50
|
de Sousa JT, Miná VG, Lopes WS, Leite VD, de Oliveira MF. Treatment of wastewater using a sequencing batch reactor. ENVIRONMENTAL TECHNOLOGY 2013; 34:1035-1042. [PMID: 23837355 DOI: 10.1080/09593330.2012.733419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The aim of this study was to evaluate the efficiency of two sequencing batch reactors (R1 and R2) at removing nutrient (N and P) and chemical oxygen demand (COD). The two reactors (R1 and R2) were of the same design, operating under identical cycles and had a sludge retention time of 5 d. In R1, the substrate was sewage enriched with cooked and triturated cereals. In R2, the substrate was raw sewage mixed with triturated discarded excess sludge. Respirometry tests were performed to compare the biodegradability of the substrates used during the experimental period. The efficiency of R1 in removing soluble P and N-ammonia was considerably higher (90.4 and 97.2%, respectively) than reactor R2 (60 and 39.2%, respectively). While the effluent generated by R1 contained only minor amounts of N-nitrite and N-nitrate (0.5 +/- 0.4 and 1.7 +/- 0.8 mg L(-1), respectively). The concentrations of nitrite and nitrate in the effluent from R2 were 2 and 7 times higher. The lack of biodegradable COD available for denitrification was responsible for the high concentrations of nitrite and nitrate in the effluent of R2.
Collapse
Affiliation(s)
- José Tavares de Sousa
- Department Environmental Engineering, Universidade Estadual da Paraíba, Paraiba, Brazil.
| | | | | | | | | |
Collapse
|