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Johansson G, Fedje KK, Modin O, Haeger-Eugensson M, Uhl W, Andersson-Sköld Y, Strömvall AM. Removal and release of microplastics and other environmental pollutants during the start-up of bioretention filters treating stormwater. J Hazard Mater 2024; 468:133532. [PMID: 38387172 DOI: 10.1016/j.jhazmat.2024.133532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 01/10/2024] [Accepted: 01/12/2024] [Indexed: 02/24/2024]
Abstract
Untreated stormwater is a major source of microplastics, organic pollutants, metals, and nutrients in urban water courses. The aim of this study was to improve the knowledge about the start-up periods of bioretention filters. A rain garden pilot facility with 13 bioretention filters was constructed and stormwater from a highway and adjacent impervious surfaces was used for irrigation for ∼12 weeks. Selected plants (Armeria maritima, Hippophae rhamnoides, Juncus effusus, and Festuca rubra) was planted in ten filters. Stormwater percolated through the filters containing waste-to-energy bottom ash, biochar, or Sphagnum peat, mixed with sandy loam. Influent and effluent samples were taken to evaluate removal of the above-mentioned pollutants. All filters efficiently removed microplastics >10 µm, organic pollutants, and most metals. Copper leached from all filters initially but was significantly reduced in the biochar filters at the end of the period, while the other filters showed a declining trend. All filters leached nutrients initially, but concentrations decreased over time, and the biochar filters had efficiently reduced nitrogen after a few weeks. To conclude, all the filters effectively removed pollutants during the start-up period. Before being recommended for full-scale applications, the functionality of the filters after a longer period of operation should be evaluated.
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Affiliation(s)
- Glenn Johansson
- Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, SE-41296 Gothenburg, Sweden.
| | - Karin Karlfeldt Fedje
- Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, SE-41296 Gothenburg, Sweden; Recycling and Waste Management, Renova AB, Box 156, Gothenburg SE-40122, Sweden
| | - Oskar Modin
- Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, SE-41296 Gothenburg, Sweden
| | | | - Wolfgang Uhl
- Aquateam COWI AS, Karvesvingen 2, 0579 Oslo, Norway
| | - Yvonne Andersson-Sköld
- Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, SE-41296 Gothenburg, Sweden; Swedish National Road and Transport Research Institute Linköping (VTI), Box 8072, SE-40278 Gothenburg, Sweden
| | - Ann-Margret Strömvall
- Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, SE-41296 Gothenburg, Sweden
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Suarez C, Rosenqvist T, Dimitrova I, Sedlacek CJ, Modin O, Paul CJ, Hermansson M, Persson F. Biofilm colonization and succession in a full-scale partial nitritation-anammox moving bed biofilm reactor. Microbiome 2024; 12:51. [PMID: 38475926 DOI: 10.1186/s40168-024-01762-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 01/09/2024] [Indexed: 03/14/2024]
Abstract
BACKGROUND Partial nitritation-anammox (PNA) is a biological nitrogen removal process commonly used in wastewater treatment plants for the treatment of warm and nitrogen-rich sludge liquor from anaerobic digestion, often referred to as sidestream wastewater. In these systems, biofilms are frequently used to retain biomass with aerobic ammonia-oxidizing bacteria (AOB) and anammox bacteria, which together convert ammonium to nitrogen gas. Little is known about how these biofilm communities develop, and whether knowledge about the assembly of biofilms in natural communities can be applied to PNA biofilms. RESULTS We followed the start-up of a full-scale PNA moving bed biofilm reactor for 175 days using shotgun metagenomics. Environmental filtering likely restricted initial biofilm colonization, resulting in low phylogenetic diversity, with the initial microbial community comprised mainly of Proteobacteria. Facilitative priority effects allowed further biofilm colonization, with the growth of initial aerobic colonizers promoting the arrival and growth of anaerobic taxa like methanogens and anammox bacteria. Among the early colonizers were known 'oligotrophic' ammonia oxidizers including comammox Nitrospira and Nitrosomonas cluster 6a AOB. Increasing the nitrogen load in the bioreactor allowed colonization by 'copiotrophic' Nitrosomonas cluster 7 AOB and resulted in the exclusion of the initial ammonia- and nitrite oxidizers. CONCLUSIONS We show that complex dynamic processes occur in PNA microbial communities before a stable bioreactor process is achieved. The results of this study not only contribute to our knowledge about biofilm assembly and PNA bioreactor start-up but could also help guide strategies for the successful implementation of PNA bioreactors. Video Abstract.
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Affiliation(s)
- Carolina Suarez
- Division of Water Resources Engineering, Faculty of Engineering LTH, Lund University, Lund, Sweden.
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden.
| | - Tage Rosenqvist
- Division of Applied Microbiology, Department of Chemistry, Lund University, Lund, Sweden
| | | | - Christopher J Sedlacek
- Division of Microbial Ecology, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
| | - Oskar Modin
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Catherine J Paul
- Division of Water Resources Engineering, Faculty of Engineering LTH, Lund University, Lund, Sweden
- Division of Applied Microbiology, Department of Chemistry, Lund University, Lund, Sweden
| | - Malte Hermansson
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Frank Persson
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden
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Norén A, Strömvall AM, Rauch S, Andersson-Sköld Y, Modin O, Karlfeldt Fedje K. The effects of electrochemical pretreatment and curing environment on strength and leaching of stabilized/solidified contaminated sediment. Environ Sci Pollut Res Int 2024; 31:5866-5880. [PMID: 38133763 PMCID: PMC10799133 DOI: 10.1007/s11356-023-31477-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 12/06/2023] [Indexed: 12/23/2023]
Abstract
Stabilization and solidification (S/S) is known to improve the structural properties of sediment and reduce contaminant mobility, enabling the utilization of dredged contaminated sediment. Further reduction of contaminants (e.g., tributyltin (TBT) and metals) can be done using electrochemical treatment prior to S/S and could potentially minimize contaminant leaching. This is the first study on how electrochemical pretreatment affects the strength and leaching properties of stabilized sediments. It also investigates how salinity and organic carbon in the curing liquid affect the stabilized sediment.The results showed that the electrolysis reduced the content of TBT by 22% and zinc by 44% in the sediment. The electrolyzed stabilized samples met the requirements for compression strength and had a reduced surface leaching of zinc. Curing in saline water was beneficial for strength development and reduced the leaching of TBT compared to curing in fresh water. The results indicate that pretreatment prior to stabilization could be beneficial in reducing contaminant leaching and recovering metals from the sediment. The conclusion is that a better understanding of the changes in the sediment caused by electrochemical treatment and how these changes interact with stabilization reactions is needed. In addition, it is recommended to investigate the strength and leaching behavior in environments similar to the intended in situ conditions.
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Affiliation(s)
- Anna Norén
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, 412 96, Gothenburg, Sweden
| | - Ann-Margret Strömvall
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, 412 96, Gothenburg, Sweden
| | - Sebastien Rauch
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, 412 96, Gothenburg, Sweden
| | - Yvonne Andersson-Sköld
- Swedish National Road and Transport Research Institute (VTI), Box 8072, 402 78, Gothenburg, Sweden
- Division of Geology and Geotechnics, Department of Architecture and Civil Engineering, Chalmers University of Technology, 412 96, Gothenburg, Sweden
| | - Oskar Modin
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, 412 96, Gothenburg, Sweden
| | - Karin Karlfeldt Fedje
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, 412 96, Gothenburg, Sweden.
- Recycling and Waste Management, Renova AB, Box 156, 401 22, Gothenburg, Sweden.
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Abadikhah M, Liu M, Persson F, Wilén BM, Farewell A, Sun J, Modin O. Effect of anode material and dispersal limitation on the performance and biofilm community in microbial electrolysis cells. Biofilm 2023; 6:100161. [PMID: 37859795 PMCID: PMC10582064 DOI: 10.1016/j.bioflm.2023.100161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 10/05/2023] [Accepted: 10/08/2023] [Indexed: 10/21/2023] Open
Abstract
In a microbial electrolysis cell (MEC), the oxidization of organic compounds is facilitated by an electrogenic biofilm on the anode surface. The biofilm community composition determines the function of the system. Both deterministic and stochastic factors affect the community, but the relative importance of different factors is poorly understood. Anode material is a deterministic factor as materials with different properties may select for different microorganisms. Ecological drift is a stochastic factor, which is amplified by dispersal limitation between communities. Here, we compared the effects of three anode materials (graphene, carbon cloth, and nickel) with the effect of dispersal limitation on the function and biofilm community assembly. Twelve MECs were operated for 56 days in four hydraulically connected loops and shotgun metagenomic sequencing was used to analyse the microbial community composition on the anode surfaces at the end of the experiment. The anode material was the most important factor affecting the performance of the MECs, explaining 54-80 % of the variance observed in peak current density, total electric charge generation, and start-up lag time, while dispersal limitation explained 10-16 % of the variance. Carbon cloth anodes had the highest current generation and shortest lag time. However, dispersal limitation was the most important factor affecting microbial community structure, explaining 61-98 % of the variance in community diversity, evenness, and the relative abundance of the most abundant taxa, while anode material explained 0-20 % of the variance. The biofilms contained nine Desulfobacterota metagenome-assembled genomes (MAGs), which made up 64-89 % of the communities and were likely responsible for electricity generation in the MECs. Different MAGs dominated in different MECs. Particularly two different genotypes related to Geobacter benzoatilyticus competed for dominance on the anodes and reached relative abundances up to 83 %. The winning genotype was the same in all MECs that were hydraulically connected irrespective of anode material used.
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Affiliation(s)
- Marie Abadikhah
- Water Environment Technology, Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Ming Liu
- Key Laboratory of Optoelectronics Technology, Beijing University of Technology, Beijing, 100124, China
| | - Frank Persson
- Water Environment Technology, Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Britt-Marie Wilén
- Water Environment Technology, Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Anne Farewell
- Chemistry and Molecular Biology, University of Gothenburg, Sweden
| | - Jie Sun
- College of Physics and Information Engineering, Fuzhou University, and Fujian Science and Technology Innovation Laboratory for Optoelectronic Information of China, Fuzhou, 350100, China
- Microtechnology and Nanoscience, Chalmers University of Technology, Gothenburg, Sweden
| | - Oskar Modin
- Water Environment Technology, Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden
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Liébana R, Modin O, Persson F, Hermansson M, Wilén BM. Resistance of aerobic granular sludge microbiomes to periodic loss of biomass. Biofilm 2023; 6:100145. [PMID: 37575957 PMCID: PMC10415711 DOI: 10.1016/j.bioflm.2023.100145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 07/07/2023] [Accepted: 07/26/2023] [Indexed: 08/15/2023] Open
Abstract
Granular sludge is a biofilm process used for wastewater treatment which is currently being implemented worldwide. It is important to understand how disturbances affect the microbial community and performance of reactors. Here, two acetate-fed replicate reactors were inoculated with acclimatized sludge and the reactor performance, and the granular sludge microbial community succession were studied for 149 days. During this time, the microbial community was challenged by periodically removing half of the reactor biomass, subsequently increasing the food-to-microorganism (F/M) ratio. Diversity analysis together with null models show that overall, the microbial communities were resistant to the disturbances, observing some minor effects on polyphosphate-accumulating and denitrifying microbial communities and their associated reactor functions. Community turnover was driven by drift and random granule loss, and stochasticity was the governing ecological process for community assembly. These results evidence the aerobic granular sludge process as a robust system for wastewater treatment.
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Affiliation(s)
- Raquel Liébana
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Sven Hultins gata 6, SE 412 96, Gothenburg, Sweden
- AZTI, Marine Research Division, Basque Research Technology Alliance (BRTA), Txatxarramendi Ugartea z/g, 48395, Sukarrieta, Bizkaia, Spain
| | - Oskar Modin
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Sven Hultins gata 6, SE 412 96, Gothenburg, Sweden
| | - Frank Persson
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Sven Hultins gata 6, SE 412 96, Gothenburg, Sweden
| | - Malte Hermansson
- Department of Chemistry and Molecular Biology, University of Gothenburg, Medicinaregatan 9E, SE-413 90, Gothenburg, Sweden
| | - Britt-Marie Wilén
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Sven Hultins gata 6, SE 412 96, Gothenburg, Sweden
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Neth M, Mattsson A, Wilén BM, Modin O. Weighted score ratios (WRS) give transparent weighting in multicriteria sustainability assessments - A case study on removal of pharmaceutical residues from wastewater. Sci Total Environ 2023:164792. [PMID: 37321507 DOI: 10.1016/j.scitotenv.2023.164792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 05/30/2023] [Accepted: 06/08/2023] [Indexed: 06/17/2023]
Abstract
Sustainability assessment using multicriteria analysis (MCA) is a structured way of including criteria from the three sustainability dimensions (environmental, economic, and social) when comparing different alternatives. A problem with the conventional MCA methods is that the consequences of the weights given to different criteria are not transparent. Here, we amend the simple additive weighting MCA method with weighted score ratios (WSRs), which are used during the sustainability assessment to show how the weights affect the valuation of the criteria (e.g., cost per kg CO2e). This enables comparisons to other sustainability assessments and reference values from society, which increases the transparency and can make weighting more objective. We applied the method to a comparison of technologies for removal of pharmaceutical residues from wastewater. Due to growing concern about the effects that pharmaceutical residues can have on our environment, implementations of advanced technologies are increasing. However, they entail high requirements of energy and resources. Therefore, many aspects must be considered to make a sustainable choice of technology. In this study, a sustainability assessment was performed of ozonation, powdered activated carbon and granular activated carbon for removal of pharmaceutical residues at a large wastewater treatment plant (WWTP) in Sweden. The outcome showed that powdered activated carbon is the least sustainable choice for the studied WWTP. Whether ozonation or granular activated carbon is most sustainable depends on how climate impact and energy use are valued. The total sustainability of ozonation is affected by how the electricity is assumed to be produced, whereas for granular activated carbon it depends on whether the carbon source is of renewable or fossil origin. Using WSRs allowed the participants in the assessment to make conscious choices on how they weighted different criteria in relation to how these criteria are valued in society at large.
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Affiliation(s)
- Maria Neth
- Gryaab AB, Box 8984, 402 74 Göteborg, Sweden; Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, SE-41296 Göteborg, Sweden.
| | - Ann Mattsson
- Gryaab AB, Box 8984, 402 74 Göteborg, Sweden; Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, SE-41296 Göteborg, Sweden
| | - Britt-Marie Wilén
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, SE-41296 Göteborg, Sweden
| | - Oskar Modin
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, SE-41296 Göteborg, Sweden
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Burzio C, Mohammadi AS, Malmberg P, Modin O, Persson F, Wilén BM. Chemical Imaging of Pharmaceuticals in Biofilms for Wastewater Treatment Using Secondary Ion Mass Spectrometry. Environ Sci Technol 2023; 57:7431-7441. [PMID: 37130040 DOI: 10.1021/acs.est.2c05027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The occurrence of pharmaceuticals in the aquatic environment is a global water quality challenge for several reasons, such as deleterious effects on ecological and human health, antibiotic resistance development, and endocrine-disrupting effects on aquatic organisms. To optimize their removal from the water cycle, understanding the processes during biological wastewater treatment is crucial. Time-of-flight secondary ion mass spectrometry imaging was successfully applied to investigate and analyze the distribution of pharmaceuticals as well as endogenous molecules in the complex biological matrix of biofilms for wastewater treatment. Several compounds and their localization were identified in the biofilm section, including citalopram, ketoconazole, ketoconazole transformation products, and sertraline. The images revealed the pharmaceuticals gathered in distinct sites of the biofilm matrix. While citalopram penetrated the biofilm deeply, sertraline remained confined in its outer layer. Both pharmaceuticals seemed to mainly colocalize with phosphocholine lipids. Ketoconazole concentrated in small areas with high signal intensity. The approach outlined here presents a powerful strategy for visualizing the chemical composition of biofilms for wastewater treatment and demonstrates its promising utility for elucidating the mechanisms behind pharmaceutical and antimicrobial removal in biological wastewater treatment.
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Affiliation(s)
- Cecilia Burzio
- Department of Architecture and Civil Engineering, Chalmers University of Technology, 41296 Gothenburg, Sweden
| | - Amir Saeid Mohammadi
- Department of Architecture and Civil Engineering, Chalmers University of Technology, 41296 Gothenburg, Sweden
| | - Per Malmberg
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, 41296 Gothenburg, Sweden
| | - Oskar Modin
- Department of Architecture and Civil Engineering, Chalmers University of Technology, 41296 Gothenburg, Sweden
| | - Frank Persson
- Department of Architecture and Civil Engineering, Chalmers University of Technology, 41296 Gothenburg, Sweden
| | - Britt-Marie Wilén
- Department of Architecture and Civil Engineering, Chalmers University of Technology, 41296 Gothenburg, Sweden
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8
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Abadikhah M, Rodriguez MDC, Persson F, Wilén BM, Farewell A, Modin O. Evidence of competition between electrogens shaping electroactive microbial communities in microbial electrolysis cells. Front Microbiol 2022; 13:959211. [PMID: 36590422 PMCID: PMC9800620 DOI: 10.3389/fmicb.2022.959211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 11/28/2022] [Indexed: 12/23/2022] Open
Abstract
In single-chamber microbial electrolysis cells (MECs), organic compounds are oxidized at the anode, liberating electrons that are used for hydrogen evolution at the cathode. Microbial communities on the anode and cathode surfaces and in the bulk liquid determine the function of the MEC. The communities are complex, and their assembly processes are poorly understood. We investigated MEC performance and community composition in nine MECs with a carbon cloth anode and a cathode of carbon nanoparticles, titanium, or stainless steel. Differences in lag time during the startup of replicate MECs suggested that the initial colonization by electrogenic bacteria was stochastic. A network analysis revealed negative correlations between different putatively electrogenic Deltaproteobacteria on the anode. Proximity to the conductive anode surface is important for electrogens, so the competition for space could explain the observed negative correlations. The cathode communities were dominated by hydrogen-utilizing taxa such as Methanobacterium and had a much lower proportion of negative correlations than the anodes. This could be explained by the diffusion of hydrogen throughout the cathode biofilms, reducing the need to compete for space.
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Affiliation(s)
- Marie Abadikhah
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden,*Correspondence: Marie Abadikhah, ✉
| | - Miguel de Celis Rodriguez
- Department of Genetics, Physiology and Microbiology, Complutense University of Madrid, Madrid, Spain
| | - Frank Persson
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Britt-Marie Wilén
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Anne Farewell
- Institute of Chemistry and Molecular Biology and the Center for Antibiotic Resistance Research, University of Gothenburg, Gothenburg, Sweden
| | - Oskar Modin
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden
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Burzio C, Ekholm J, Modin O, Falås P, Svahn O, Persson F, van Erp T, Gustavsson DJI, Wilén BM. Removal of organic micropollutants from municipal wastewater by aerobic granular sludge and conventional activated sludge. J Hazard Mater 2022; 438:129528. [PMID: 35999740 DOI: 10.1016/j.jhazmat.2022.129528] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 06/02/2022] [Accepted: 07/01/2022] [Indexed: 06/15/2023]
Abstract
Removal performances of organic micropollutants by conventional activated sludge (CAS) and aerobic granular sludge (AGS) were investigated at a full-scale wastewater treatment plant. Lab-scale kinetic experiments were performed to assess the micropollutant transformation rates under oxic and anoxic conditions. Transformation rates were used to model the micropollutant removal in the full-scale processes. Metagenomic sequencing was used to compare the microbial communities and antimicrobial resistance genes of the CAS and AGS systems. Higher transformation ability was observed for CAS compared to AGS for most compounds, both at the full-scale plant and in the complementary batch experiments. Oxic conditions supported the transformation of several micropollutants with faster and/or comparable rates compared to anoxic conditions. The estimated transformation rates from batch experiments adequately predicted the removal for most micropollutants in the full-scale processes. While the compositions in microbial communities differed between AGS and CAS, the full-scale biological reactors shared similar resistome profiles. Even though granular biomass showed lower potential for micropollutant transformation, AGS systems had somewhat higher gene cluster diversity compared to CAS, which could be related to a higher functional diversity. Micropollutant exposure to biomass or mass transfer limitations, therefore played more important roles in the observed differences in OMP removal.
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Affiliation(s)
- Cecilia Burzio
- Department of Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg 41296, Sweden.
| | - Jennifer Ekholm
- Department of Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg 41296, Sweden
| | - Oskar Modin
- Department of Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg 41296, Sweden
| | - Per Falås
- Department of Chemical Engineering, Lund University, PO Box 124, Lund 22100, Sweden
| | - Ola Svahn
- Department of Environmental Science and Bioscience, Kristianstad University, Kristianstad 29139, Sweden
| | - Frank Persson
- Department of Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg 41296, Sweden
| | - Tim van Erp
- Strömstad Municipality, Wastewater Treatment Plant Österröd, Strömstad 45233, Sweden
| | | | - Britt-Marie Wilén
- Department of Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg 41296, Sweden
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Neth M, Mattsson A, I'Ons D, Tumlin S, Arnell M, Blom L, Wilén BM, Modin O. A collaborative planning process to develop future scenarios for wastewater systems. J Environ Manage 2022; 316:115202. [PMID: 35550956 DOI: 10.1016/j.jenvman.2022.115202] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 03/28/2022] [Accepted: 04/27/2022] [Indexed: 06/15/2023]
Abstract
Wastewater infrastructure has a long lifetime and is subject to changing conditions and demands. When plans are made to upgrade or build new infrastructure, transdisciplinary planning processes and a robust analysis of future conditions are needed to make sustainable choices. Here, we provide a stepwise collaborative planning process in which future scenarios are developed together with local stakeholders and expert groups. The process was implemented at one of the largest wastewater treatment plants (WWTPs) in Scandinavia. With a combination of workshops and the use of a web-based digital tool, future scenarios including flows, pollutant loads, and treatment requirements could be created. Furthermore, sustainability prioritizations affecting the WWTP, were identified. The future scenarios developed for the WWTP in the case study, predict stricter and new regulations, constant or lower future loads and ambiguous future flows. The highest ranked sustainability priority was low resource and energy consumption together with low CO2 footprint. The quantified future scenarios developed in the planning process were used as input to a process model to show the consequences they would have on the WWTP in the case study. Applying this collaborative process revealed future scenarios with many, sometimes conflicting, expectations on future WWTPs. It also highlighted needs for improvements of both the collection system and the WWTP.
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Affiliation(s)
- Maria Neth
- Gryaab AB, Box 8984, 402 74, Göteborg, Sweden; Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, SE-41296, Göteborg, Sweden.
| | - Ann Mattsson
- Gryaab AB, Box 8984, 402 74, Göteborg, Sweden; Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, SE-41296, Göteborg, Sweden
| | - David I'Ons
- Gryaab AB, Box 8984, 402 74, Göteborg, Sweden
| | | | - Magnus Arnell
- Unit of Urban Water Management, RISE Research Institutes of Sweden, Gjuterigatan 1D, SE-58273, Linköping, Sweden; Division of Industrial Electrical Engineering and Automation (IEA), Department of Biomedical Engineering, Lund University, PO Box 118, SE-22100, Lund, Sweden
| | - Lena Blom
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, SE-41296, Göteborg, Sweden; City of Gothenburg, Department of Sustainable Waste and Water, Box 123, SE-424 23, Angered, Sweden
| | - Britt-Marie Wilén
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, SE-41296, Göteborg, Sweden
| | - Oskar Modin
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, SE-41296, Göteborg, Sweden
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Modin O, Fuad N, Abadikhah M, I'Ons D, Ossiansson E, Gustavsson DJ, Edefell E, Suarez C, Persson F, Wilén BM. A relationship between phages and organic carbon in wastewater treatment plant effluents. Water Res X 2022; 16:100146. [PMID: 35761925 PMCID: PMC9233278 DOI: 10.1016/j.wroa.2022.100146] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 05/27/2022] [Accepted: 06/15/2022] [Indexed: 06/10/2023]
Abstract
With stringent effluent requirements and the implementation of new processes for micropollutant removal, it is increasingly important for wastewater treatment plants (WWTPs) to understand the factors affecting effluent quality. Phages (viruses infecting prokaryotes) are abundant in the biological treatment processes. They can contribute to organic carbon in the treated effluent both because they are organic in nature and occur in the effluent and because they cause lysis of microorganisms. Today very little is known about the effects of phages on effluent quality. The goal of this study was, therefore, to determine the relationship between phages and organic carbon in WWTP effluents. We also examined the diversity, taxonomy, and host-association of DNA phages using metagenomics. Effluent samples were collected from four WWTPs treating municipal wastewater. Significant differences in both organic carbon and virus-like particle concentrations were observed between the plants and there was a linear relationship between the two parameters. The phage communities were diverse with many members being taxonomically unclassified. Putative hosts were dominated by bacteria known to be abundant in activated sludge systems such as Comamonadaceae. The composition of phages differed between the WWTPs, suggesting that local conditions shape the communities. Overall, our findings suggest that the abundance and composition of phages are related to effluent quality. Thus, there is a need for further research clarifying the association between phage dynamics and WWTP function.
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Affiliation(s)
- Oskar Modin
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg SE-412 96, Sweden
| | - Nafis Fuad
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg SE-412 96, Sweden
- Department of Civil and Environmental Engineering, University of Connecticut, USA
| | - Marie Abadikhah
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg SE-412 96, Sweden
| | | | - Elin Ossiansson
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg SE-412 96, Sweden
- VA SYD, P.O. Box 191, Malmö SE-2021, Sweden
| | - David J.I. Gustavsson
- VA SYD, P.O. Box 191, Malmö SE-2021, Sweden
- Sweden Water Research, c/o Ideon Science Park, Scheelevägen 15, Lund SE-223 70, Sweden
| | - Ellen Edefell
- Sweden Water Research, c/o Ideon Science Park, Scheelevägen 15, Lund SE-223 70, Sweden
- Department of Chemical Engineering, Lund University, PO Box 124, Lund SE-221 00, Sweden
| | - Carolina Suarez
- Division of Water Resources Engineering, Faculty of Engineering LTH, Lund University, Box 118, Lund SE-221 00, Sweden
| | - Frank Persson
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg SE-412 96, Sweden
| | - Britt-Marie Wilén
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg SE-412 96, Sweden
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Suarez C, Sedlacek CJ, Gustavsson DJI, Eiler A, Modin O, Hermansson M, Persson F. Disturbance-based management of ecosystem services and disservices in partial nitritation-anammox biofilms. NPJ Biofilms Microbiomes 2022; 8:47. [PMID: 35676296 PMCID: PMC9178042 DOI: 10.1038/s41522-022-00308-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 05/13/2022] [Indexed: 11/28/2022] Open
Abstract
The resistance and resilience provided by functional redundancy, a common feature of microbial communities, is not always advantageous. An example is nitrite oxidation in partial nitritation-anammox (PNA) reactors designed for nitrogen removal in wastewater treatment, where suppression of nitrite oxidizers like Nitrospira is sought. In these ecosystems, biofilms provide microhabitats with oxygen gradients, allowing the coexistence of aerobic and anaerobic bacteria. We designed a disturbance experiment where PNA biofilms, treating water from a high-rate activated sludge process, were constantly or intermittently exposed to anaerobic sidestream wastewater, which has been proposed to inhibit nitrite oxidizers. With increasing sidestream exposure we observed decreased abundance, alpha-diversity, functional versatility, and hence functional redundancy, among Nitrospira in the PNA biofilms, while the opposite patterns were observed for anammox bacteria within Brocadia. At the same time, species turnover was observed for aerobic ammonia-oxidizing Nitrosomonas populations. The different exposure regimens were associated with metagenomic assembled genomes of Nitrosomonas, Nitrospira, and Brocadia, encoding genes related to N-cycling, substrate usage, and osmotic stress response, possibly explaining the three different patterns by niche differentiation. These findings imply that disturbances can be used to manage the functional redundancy of biofilm microbiomes in a desirable direction, which should be considered when designing operational strategies for wastewater treatment.
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Suarez C, Dalcin Martins P, Jetten M, Karačić S, Wilén BM, Modin O, Hagelia P, Hermansson M, Persson F. Metagenomic evidence of a novel family of anammox bacteria in a subsea environment. Environ Microbiol 2022; 24:2348-2360. [PMID: 35415863 PMCID: PMC9325076 DOI: 10.1111/1462-2920.16006] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 04/07/2022] [Indexed: 12/02/2022]
Abstract
Bacteria in the order ‘Candidatus Brocadiales’ within the phylum Planctomycetes (Planctomycetota) have the remarkable ability to perform anaerobic ammonium oxidation (anammox). Two families of anammox bacteria with different biogeographical distributions have been reported, marine Ca. Scalinduaceae and freshwater Ca. Brocadiaceae. Here we report evidence of three new species within a novel genus and family of anammox bacteria, which were discovered in biofilms of a subsea road tunnel under a fjord in Norway. In this particular ecosystem, the nitrogen cycle is likely fuelled by ammonia from organic matter degradation in the fjord sediments and the rock mass above the tunnel, resulting in the growth of biofilms where anammox bacteria can thrive under oxygen limitation. We resolved several metagenome‐assembled genomes (MAGs) of anammox bacteria, including three Ca. Brocadiales MAGs that could not be classified at the family level. MAGs of this novel family had all the diagnostic genes for a full anaerobic ammonium oxidation pathway in which nitrite was probably reduced by a NirK‐like reductase. A survey of published molecular data indicated that this new family of anammox bacteria occurs in many marine sediments, where its members presumably would contribute to nitrogen loss.
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Affiliation(s)
- Carolina Suarez
- Division of Water Resources Engineering, Faculty of Engineering LTH, Lund University, Lund, Sweden.,Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Paula Dalcin Martins
- Department of Microbiology, RIBES, Radboud Institute for Biological and Environmental Sciences, Radboud University, Nijmegen, Netherlands
| | - Mike Jetten
- Department of Microbiology, RIBES, Radboud Institute for Biological and Environmental Sciences, Radboud University, Nijmegen, Netherlands
| | - Sabina Karačić
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Britt Marie Wilén
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Oskar Modin
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Per Hagelia
- Construction Division, The Norwegian Public Roads Administration, Oslo, Norway
| | - Malte Hermansson
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Frank Persson
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden
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Norén A, Lointier C, Modin O, Strömvall AM, Rauch S, Andersson-Sköld Y, Karlfeldt Fedje K. Removal of organotin compounds and metals from Swedish marine sediment using Fenton's reagent and electrochemical treatment. Environ Sci Pollut Res Int 2022; 29:27988-28004. [PMID: 34985631 PMCID: PMC8993779 DOI: 10.1007/s11356-021-17554-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 11/12/2021] [Indexed: 06/13/2023]
Abstract
Metal and tributyltin (TBT) contaminated sediments are problematic for sediment managers and the environment. This study is the first to compare Fenton's reagent and electrochemical treatment as remediation methods for the removal of TBT and metals using laboratory-scale experiments on contaminated dredged sediment. The costs and the applicability of the developed methods were also compared and discussed. Both methods removed > 98% TBT from TBT-spiked sediment samples, while Fenton's reagent removed 64% of the TBT and electrolysis 58% of the TBT from non-spiked samples. TBT in water phase was effectively degraded in both experiments on spiked water and in leachates during the treatment of the sediment. Positive correlations were observed between TBT removal and the added amount of hydrogen peroxide and current density. Both methods removed metals from the sediment, but Fenton's reagent was identified as the most potent option for effective removal of both metals and TBT, especially from highly metal-contaminated sediment. However, due to risks associated with the required chemicals and low pH level in the sediment residue following the Fenton treatment, electrochemical treatment could be a more sustainable option for treating larger quantities of contaminated sediment.
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Affiliation(s)
- Anna Norén
- Department of Architecture and Civil Engineering, Division of Water Environment Technology, Chalmers University of Technology, 412 96, Gothenburg, Sweden.
| | - Célia Lointier
- Department of Architecture and Civil Engineering, Division of Water Environment Technology, Chalmers University of Technology, 412 96, Gothenburg, Sweden
| | - Oskar Modin
- Department of Architecture and Civil Engineering, Division of Water Environment Technology, Chalmers University of Technology, 412 96, Gothenburg, Sweden
| | - Ann-Margret Strömvall
- Department of Architecture and Civil Engineering, Division of Water Environment Technology, Chalmers University of Technology, 412 96, Gothenburg, Sweden
| | - Sebastien Rauch
- Department of Architecture and Civil Engineering, Division of Water Environment Technology, Chalmers University of Technology, 412 96, Gothenburg, Sweden
| | - Yvonne Andersson-Sköld
- Swedish National Road and Transport Research Institute (VTI), Box 8072, 402 78, Gothenburg, Sweden
- Department of Architecture and Civil Engineering, Division of Geology and Geotechnics, Chalmers University of Technology, 412 96, Gothenburg, Sweden
| | - Karin Karlfeldt Fedje
- Department of Architecture and Civil Engineering, Division of Water Environment Technology, Chalmers University of Technology, 412 96, Gothenburg, Sweden
- Recycling and Waste Management, Renova AB, Box 156, 401 22, Gothenburg, Sweden
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Svensson N, Norén A, Modin O, Karlfeldt Fedje K, Rauch S, Strömvall AM, Andersson-Sköld Y. Integrated cost and environmental impact assessment of management options for dredged sediment. Waste Manag 2022; 138:30-40. [PMID: 34847467 DOI: 10.1016/j.wasman.2021.11.031] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 10/25/2021] [Accepted: 11/19/2021] [Indexed: 06/13/2023]
Abstract
Large quantities of sediment must be dredged regularly to enable marine transport and trade. The sediments are often polluted, with e.g. metals, which limits the management options. The aim of this study has been to assess costs and environmental impacts (impact on climate, marine organisms, etc.) of different management options for polluted dredged sediment, by combining life-cycle assessment (LCA) of the climate impact, scoring of other environmental aspects and a cost evaluation. This approach has been used to study both traditional and new management alternatives for a real port case. The studied options include landfilling, deep-sea disposal, construction of a port area using a stabilization and solidification (S/S) method, and a combination of the aforementioned methods with the innovative option of metal recovery through sediment electrolysis. The LCA showed that deep-sea disposal had the lowest climate impact. The assessment of the other environmental impacts showed that the result varied depending on the pollution level and the time perspective used (short or long-term). Using sediment for construction had the highest climate impact, although other environmental impacts were comparably low. Electrolysis was found to be suitable for highly polluted sediments, as it left the sediment cleaner and enabled recovery of precious metals, however the costs were high. The results highlight the complexity of comparing different environmental impacts and the benefits of using integrated assessments to provide clarity, and to evaluate both the synergetic and counteracting effects associated with the investigated scenarios and may aid early-stage decision making.
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Affiliation(s)
- Nina Svensson
- Swedish National Road and Transport Research Institute (VTI), Malvinas väg 6, Stockholm SE-114 28, Sweden.
| | - Anna Norén
- Department of Architecture and Civil Engineering, Division of Water Environment Technology, Chalmers University of Technology, Gothenburg SE-412 96, Sweden
| | - Oskar Modin
- Department of Architecture and Civil Engineering, Division of Water Environment Technology, Chalmers University of Technology, Gothenburg SE-412 96, Sweden
| | - Karin Karlfeldt Fedje
- Department of Architecture and Civil Engineering, Division of Water Environment Technology, Chalmers University of Technology, Gothenburg SE-412 96, Sweden; Recycling and Waste Management, Renova AB, Box 156, Gothenburg SE-401 22, Sweden
| | - Sebastien Rauch
- Department of Architecture and Civil Engineering, Division of Water Environment Technology, Chalmers University of Technology, Gothenburg SE-412 96, Sweden
| | - Ann-Margret Strömvall
- Department of Architecture and Civil Engineering, Division of Water Environment Technology, Chalmers University of Technology, Gothenburg SE-412 96, Sweden
| | - Yvonne Andersson-Sköld
- Swedish National Road and Transport Research Institute (VTI), Malvinas väg 6, Stockholm SE-114 28, Sweden; Department of Architecture and Civil Engineering, Division of Geology and geotechnics, Chalmers University of Technology, Gothenburg SE-412 96, Sweden
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Modin O, Liébana R, Saheb-Alam S, Wilén BM, Suarez C, Hermansson M, Persson F. Correction to: Hill-based dissimilarity indices and null models for analysis of microbial community assembly. Microbiome 2020; 8:148. [PMID: 33115538 PMCID: PMC7594297 DOI: 10.1186/s40168-020-00942-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
An amendment to this paper has been published and can be accessed via the original article.
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Affiliation(s)
- Oskar Modin
- Water Environment Technology, Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden.
| | - Raquel Liébana
- Water Environment Technology, Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Soroush Saheb-Alam
- Water Environment Technology, Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Britt-Marie Wilén
- Water Environment Technology, Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Carolina Suarez
- Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Malte Hermansson
- Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Frank Persson
- Water Environment Technology, Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden
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Modin O, Liébana R, Saheb-Alam S, Wilén BM, Suarez C, Hermansson M, Persson F. Hill-based dissimilarity indices and null models for analysis of microbial community assembly. Microbiome 2020; 8:132. [PMID: 32917275 PMCID: PMC7488682 DOI: 10.1186/s40168-020-00909-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 08/19/2020] [Indexed: 06/10/2023]
Abstract
BACKGROUND High-throughput amplicon sequencing of marker genes, such as the 16S rRNA gene in Bacteria and Archaea, provides a wealth of information about the composition of microbial communities. To quantify differences between samples and draw conclusions about factors affecting community assembly, dissimilarity indices are typically used. However, results are subject to several biases, and data interpretation can be challenging. The Jaccard and Bray-Curtis indices, which are often used to quantify taxonomic dissimilarity, are not necessarily the most logical choices. Instead, we argue that Hill-based indices, which make it possible to systematically investigate the impact of relative abundance on dissimilarity, should be used for robust analysis of data. In combination with a null model, mechanisms of microbial community assembly can be analyzed. Here, we also introduce a new software, qdiv, which enables rapid calculations of Hill-based dissimilarity indices in combination with null models. RESULTS Using amplicon sequencing data from two experimental systems, aerobic granular sludge (AGS) reactors and microbial fuel cells (MFC), we show that the choice of dissimilarity index can have considerable impact on results and conclusions. High dissimilarity between replicates because of random sampling effects make incidence-based indices less suited for identifying differences between groups of samples. Determining a consensus table based on count tables generated with different bioinformatic pipelines reduced the number of low-abundant, potentially spurious amplicon sequence variants (ASVs) in the data sets, which led to lower dissimilarity between replicates. Analysis with a combination of Hill-based indices and a null model allowed us to show that different ecological mechanisms acted on different fractions of the microbial communities in the experimental systems. CONCLUSIONS Hill-based indices provide a rational framework for analysis of dissimilarity between microbial community samples. In combination with a null model, the effects of deterministic and stochastic community assembly factors on taxa of different relative abundances can be systematically investigated. Calculations of Hill-based dissimilarity indices in combination with a null model can be done in qdiv, which is freely available as a Python package ( https://github.com/omvatten/qdiv ). In qdiv, a consensus table can also be determined from several count tables generated with different bioinformatic pipelines. Video Abstract.
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Affiliation(s)
- Oskar Modin
- Water Environment Technology, Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Raquel Liébana
- Water Environment Technology, Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Soroush Saheb-Alam
- Water Environment Technology, Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Britt-Marie Wilén
- Water Environment Technology, Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Carolina Suarez
- Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Malte Hermansson
- Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Frank Persson
- Water Environment Technology, Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden
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Rahimi S, Modin O, Mijakovic I. Technologies for biological removal and recovery of nitrogen from wastewater. Biotechnol Adv 2020; 43:107570. [PMID: 32531318 DOI: 10.1016/j.biotechadv.2020.107570] [Citation(s) in RCA: 109] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 05/22/2020] [Accepted: 05/22/2020] [Indexed: 12/11/2022]
Abstract
Water contamination is a growing environmental issue. Several harmful effects on human health and the environment are attributed to nitrogen contamination of water sources. Consequently, many countries have strict regulations on nitrogen compound concentrations in wastewater effluents. Wastewater treatment is carried out using energy- and cost-intensive biological processes, which convert nitrogen compounds into innocuous dinitrogen gas. On the other hand, nitrogen is also an essential nutrient. Artificial fertilizers are produced by fixing dinitrogen gas from the atmosphere, in an energy-intensive chemical process. Ideally, we should be able to spend less energy and chemicals to remove nitrogen from wastewater and instead recover a fraction of it for use in fertilizers and similar applications. In this review, we present an overview of various technologies of biological nitrogen removal including nitrification, denitrification, anaerobic ammonium oxidation (anammox), as well as bioelectrochemical systems and microalgal growth for nitrogen recovery. We highlighted the nitrogen removal efficiency of these systems at different temperatures and operating conditions. The advantages, practical challenges, and potential for nitrogen recovery of different treatment methods are discussed.
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Affiliation(s)
- Shadi Rahimi
- Division of Systems and Synthetic Biology, Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden.
| | - Oskar Modin
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Ivan Mijakovic
- Division of Systems and Synthetic Biology, Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden; The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark.
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Cimbritz M, Edefell E, Thörnqvist E, El-Taliawy H, Ekenberg M, Burzio C, Modin O, Persson F, Wilén BM, Bester K, Falås P. Corrigendum to "PAC dosing to an MBBR - Effects on adsorption of micropollutants, nitrification and microbial community" [Sci. Total Environ. 677 (2019) 571-579]. Sci Total Environ 2019; 685:1307. [PMID: 31189502 DOI: 10.1016/j.scitotenv.2019.05.431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Affiliation(s)
- Michael Cimbritz
- Department of Chemical Engineering, Lund University, PO Box 124, 221 00 Lund, Sweden.
| | - Ellen Edefell
- Department of Chemical Engineering, Lund University, PO Box 124, 221 00 Lund, Sweden; Sweden Water Research AB, Ideon Science Park, Scheelevägen 15, 223 70 Lund, Sweden
| | - Elias Thörnqvist
- Department of Chemical Engineering, Lund University, PO Box 124, 221 00 Lund, Sweden
| | - Haitam El-Taliawy
- Department of Environmental Science, Aarhus University, Frederiksborgsvej 399, Roskilde 4000, Denmark
| | - Maria Ekenberg
- Veolia Water Technologies AB - AnoxKaldnes, Klosterängsvägen 11A, 226 47 Lund, Sweden
| | - Cecilia Burzio
- Chalmers University of Technology, Architecture and Civil Engineering, Water Environment Technology, Sven Hultins gata 6, SE-412 96 Gothenburg, Sweden
| | - Oskar Modin
- Chalmers University of Technology, Architecture and Civil Engineering, Water Environment Technology, Sven Hultins gata 6, SE-412 96 Gothenburg, Sweden
| | - Frank Persson
- Chalmers University of Technology, Architecture and Civil Engineering, Water Environment Technology, Sven Hultins gata 6, SE-412 96 Gothenburg, Sweden
| | - Britt-Marie Wilén
- Chalmers University of Technology, Architecture and Civil Engineering, Water Environment Technology, Sven Hultins gata 6, SE-412 96 Gothenburg, Sweden
| | - Kai Bester
- Department of Environmental Science, Aarhus University, Frederiksborgsvej 399, Roskilde 4000, Denmark
| | - Per Falås
- Department of Chemical Engineering, Lund University, PO Box 124, 221 00 Lund, Sweden
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Saheb‐Alam S, Persson F, Wilén B, Hermansson M, Modin O. Response to starvation and microbial community composition in microbial fuel cells enriched on different electron donors. Microb Biotechnol 2019; 12:962-975. [PMID: 31228355 PMCID: PMC6680615 DOI: 10.1111/1751-7915.13449] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 05/21/2019] [Accepted: 05/22/2019] [Indexed: 11/30/2022] Open
Abstract
In microbial fuel cells (MFCs), microorganisms generate electrical current by oxidizing organic compounds. MFCs operated with different electron donors harbour different microbial communities, and it is unknown how that affects their response to starvation. We analysed the microbial communities in acetate- and glucose-fed MFCs and compared their responses to 10 days starvation periods. Each starvation period resulted in a 4.2 ± 1.4% reduction in electrical current in the acetate-fed MFCs and a 10.8 ± 3.9% reduction in the glucose-fed MFCs. When feed was resumed, the acetate-fed MFCs recovered immediately, whereas the glucose-fed MFCs required 1 day to recover. The acetate-fed bioanodes were dominated by Desulfuromonas spp. converting acetate into electrical current. The glucose-fed bioanodes were dominated by Trichococcus sp., functioning as a fermenter, and a member of Desulfuromonadales, using the fermentation products to generate electrical current. Suspended biomass and biofilm growing on non-conductive regions within the MFCs had different community composition than the bioanodes. However, null models showed that homogenizing dispersal of microorganisms within the MFCs affected the community composition, and in the glucose-fed MFCs, the Trichococcus sp. was abundant in all locations. The different responses to starvation can be explained by the more complex pathway requiring microbial interactions to convert glucose into electrical current.
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Affiliation(s)
- Soroush Saheb‐Alam
- Department of Architecture and Civil EngineeringDivision of Water Environment TechnologyChalmers University of TechnologyGothenburgSweden
| | - Frank Persson
- Department of Architecture and Civil EngineeringDivision of Water Environment TechnologyChalmers University of TechnologyGothenburgSweden
| | - Britt‐Marie Wilén
- Department of Architecture and Civil EngineeringDivision of Water Environment TechnologyChalmers University of TechnologyGothenburgSweden
| | - Malte Hermansson
- Chemistry and Molecular BiologyUniversity of GothenburgGothenburgSweden
| | - Oskar Modin
- Department of Architecture and Civil EngineeringDivision of Water Environment TechnologyChalmers University of TechnologyGothenburgSweden
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Cimbritz M, Edefell E, Thörnqvist E, El-Taliawy H, Ekenberg M, Burzio C, Modin O, Persson F, Wilén BM, Bester K, Falås P. PAC dosing to an MBBR - Effects on adsorption of micropollutants, nitrification and microbial community. Sci Total Environ 2019; 677:571-579. [PMID: 31067478 DOI: 10.1016/j.scitotenv.2019.04.261] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Revised: 04/15/2019] [Accepted: 04/17/2019] [Indexed: 06/09/2023]
Abstract
Two nitrifying MBBR reactors were operated in parallel, one with PAC dosing and one without, to determine the effects of PAC dosing on nitrification and micropollutant adsorption in municipal wastewater. The removal of micropollutants was evaluated for several doses of PAC and batch experiments were performed to measure adsorption kinetics and nitrification rates. The influence of PAC on the nitrifying microbial community was examined by high-throughput amplicon sequencing. Long-term operation of the pilot reactors showed that nitrification could be maintained while supplying PAC at increasing doses, as confirmed by high nitrification rates and significant abundance of nitrifying bacteria. The adsorption of organic micropollutants could be controlled by the PAC dose, and increased dosing resulted in corresponding improvements in removal efficiency. Biomass, suspended or attached to carriers, did not interfere with the adsorption of organic micropollutants. Freundlich isotherms obtained from the batch experiments were used to predict removal of organic micropollutants in the pilot reactors, suggesting that batch adsorption experiments can be used to predict micropollutant removal on a full scale. Collectively, the results show that nitrification and adsorption of organic micropollutants can be performed simultaneously in an MBBR.
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Affiliation(s)
- Michael Cimbritz
- Department of Chemical Engineering, Lund University, PO Box 124, 221 00 Lund, Sweden.
| | - Ellen Edefell
- Department of Chemical Engineering, Lund University, PO Box 124, 221 00 Lund, Sweden; Sweden Water Research AB, Ideon Science Park, Scheelevägen 15, 223 70 Lund, Sweden
| | - Elias Thörnqvist
- Department of Chemical Engineering, Lund University, PO Box 124, 221 00 Lund, Sweden
| | - Haitam El-Taliawy
- Department of Environmental Science, Aarhus University, Frederiksborgsvej 399, Roskilde 4000, Denmark
| | - Maria Ekenberg
- Veolia Water Technologies AB - AnoxKaldnes, Klosterängsvägen 11A, 226 47 Lund, Sweden
| | - Cecilia Burzio
- Chalmers University of Technology, Architecture and Civil Engineering, Water Environment Technology, Sven Hultins gata 6, SE-412 96 Gothenburg, Sweden
| | - Oskar Modin
- Chalmers University of Technology, Architecture and Civil Engineering, Water Environment Technology, Sven Hultins gata 6, SE-412 96 Gothenburg, Sweden
| | - Frank Persson
- Chalmers University of Technology, Architecture and Civil Engineering, Water Environment Technology, Sven Hultins gata 6, SE-412 96 Gothenburg, Sweden
| | - Britt-Marie Wilén
- Chalmers University of Technology, Architecture and Civil Engineering, Water Environment Technology, Sven Hultins gata 6, SE-412 96 Gothenburg, Sweden
| | - Kai Bester
- Department of Environmental Science, Aarhus University, Frederiksborgsvej 399, Roskilde 4000, Denmark
| | - Per Falås
- Department of Chemical Engineering, Lund University, PO Box 124, 221 00 Lund, Sweden
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Liébana R, Modin O, Persson F, Szabó E, Hermansson M, Wilén BM. Combined Deterministic and Stochastic Processes Control Microbial Succession in Replicate Granular Biofilm Reactors. Environ Sci Technol 2019; 53:4912-4921. [PMID: 30969774 DOI: 10.1021/acs.est.8b06669] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Granular sludge is an efficient and compact biofilm process for wastewater treatment. However, the ecological factors involved in microbial community assembly during the granular biofilm formation are poorly understood, and little is known about the reproducibility of the process. Here, three replicate bioreactors were used to investigate microbial succession during the formation of granular biofilms. We identified three successional phases. During the initial phase, the successional turnover was high and α-diversity decreased as a result of the selection of taxa adapted to grow on acetate and form aggregates. Despite these dynamic changes, the microbial communities in the replicate reactors were similar. The second successional phase occurred when the settling time was rapidly decreased to selectively retain granules in the reactors. The influence of stochasticity on succession increased and new niches were created as granules emerged, resulting in temporarily increased α-diversity. The third successional phase occurred when the settling time was kept stable and granules dominated the biomass. Turnover was low, and selection resulted in the same abundant taxa in the reactors, but drift, which mostly affected low-abundant community members, caused the community in one reactor to diverge from the other two. Even so, performance was stable and similar between reactors.
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Affiliation(s)
- Raquel Liébana
- Division of Water Environment Technology, Department of Architecture and Civil Engineering , Chalmers University of Technology , SE-412 96 Gothenburg , Sweden
| | - Oskar Modin
- Division of Water Environment Technology, Department of Architecture and Civil Engineering , Chalmers University of Technology , SE-412 96 Gothenburg , Sweden
| | - Frank Persson
- Division of Water Environment Technology, Department of Architecture and Civil Engineering , Chalmers University of Technology , SE-412 96 Gothenburg , Sweden
| | - Enikö Szabó
- Division of Water Environment Technology, Department of Architecture and Civil Engineering , Chalmers University of Technology , SE-412 96 Gothenburg , Sweden
| | - Malte Hermansson
- Department of Chemistry and Molecular Biology , University of Gothenburg , SE405 30 Gothenburg , Sweden
| | - Britt-Marie Wilén
- Division of Water Environment Technology, Department of Architecture and Civil Engineering , Chalmers University of Technology , SE-412 96 Gothenburg , Sweden
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Abstract
Aerobic methanotrophic bacteria use methane as their only source of energy and carbon. They release organic compounds that can serve as electron donors for co-existing denitrifiers. This interaction between methanotrophs and denitrifiers is known to contribute to nitrogen losses in natural environments and has also been exploited by researchers for denitrification of nitrate-contaminated wastewater. The purpose of this study was to develop a mathematical model describing aerobic methane oxidation coupled to denitrification in suspended-growth reactors. The model considered the activities of three microbial groups: aerobic methanotrophs, facultative methylotrophs, and facultative heterotrophs. The model was tested against data from the scientific literature and used to explore the effects of the oxygen mass transfer coefficient, the solids retention time, and the fraction methane in the feed gas on nitrate removal. The fraction of methane in the feed gas was found to be critical for the nitrate removal rate. A value of about 15% in air was optimal. A lower methane fraction led to excess oxygen, which was detrimental for denitrification. A higher fraction led to oxygen-limitation, which restricted the growth rate of methanotrophs in the reactor.
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Affiliation(s)
- Oskar Modin
- a Division of Water Environment Technology, Department of Architecture and Civil Engineering , Chalmers University of Technology , Gothenburg , Sweden
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24
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Wilén BM, Liébana R, Persson F, Modin O, Hermansson M. The mechanisms of granulation of activated sludge in wastewater treatment, its optimization, and impact on effluent quality. Appl Microbiol Biotechnol 2018; 102:5005-5020. [PMID: 29705957 PMCID: PMC5960003 DOI: 10.1007/s00253-018-8990-9] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 04/04/2018] [Accepted: 04/05/2018] [Indexed: 12/14/2022]
Abstract
Granular activated sludge has gained increasing interest due to its potential in treating wastewater in a compact and efficient way. It is well-established that activated sludge can form granules under certain environmental conditions such as batch-wise operation with feast-famine feeding, high hydrodynamic shear forces, and short settling time which select for dense microbial aggregates. Aerobic granules with stable structure and functionality have been obtained with a range of different wastewaters seeded with different sources of sludge at different operational conditions, but the microbial communities developed differed substantially. In spite of this, granule instability occurs. In this review, the available literature on the mechanisms involved in granulation and how it affects the effluent quality is assessed with special attention given to the microbial interactions involved. To be able to optimize the process further, more knowledge is needed regarding the influence of microbial communities and their metabolism on granule stability and functionality. Studies performed at conditions similar to full-scale such as fluctuation in organic loading rate, hydrodynamic conditions, temperature, incoming particles, and feed water microorganisms need further investigations.
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Affiliation(s)
- Britt-Marie Wilén
- Division of Water Environment Technology, Department of Architecture and Civil and Engineering, Chalmers University of Technology, SE-412 96, Gothenburg, Sweden.
| | - Raquel Liébana
- Division of Water Environment Technology, Department of Architecture and Civil and Engineering, Chalmers University of Technology, SE-412 96, Gothenburg, Sweden
| | - Frank Persson
- Division of Water Environment Technology, Department of Architecture and Civil and Engineering, Chalmers University of Technology, SE-412 96, Gothenburg, Sweden
| | - Oskar Modin
- Division of Water Environment Technology, Department of Architecture and Civil and Engineering, Chalmers University of Technology, SE-412 96, Gothenburg, Sweden
| | - Malte Hermansson
- Department of Chemistry and Molecular Biology, University of Gothenburg, SE-405 30, Gothenburg, Sweden
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Abstract
Environmental deterioration together with the need for water reuse and the increasingly restrictive legislation of water quality standards have led to a demand for compact, efficient and less energy consuming technologies for wastewater treatment. Aerobic granular sludge and membrane bioreactors (MBRs) are two technologies with several advantages, such as small footprint, high-microbial density and activity, ability to operate at high organic- and nitrogen-loading rates, and tolerance to toxicity. However, they also have some disadvantages. The aerobic granular sludge process generally requires post-treatment in order to fulfill effluent standards and MBRs suffer from fouling of the membranes. Integrating the two technologies could be a way of combining the advantages and addressing the main problems associated with both processes. The use of membranes to separate the aerobic granules from the treated water would ensure high-quality effluents suitable for reuse. Moreover, the use of granular sludge in MBRs has been shown to reduce fouling. Several recent studies have shown that the aerobic granular membrane bioreactor (AGMBR) is a promising hybrid process with many attractive features. However, major challenges that have to be addressed include how to achieve granulation and maintain granular stability during continuous operation of reactors. This paper aims to review the current state of research on AGMBR technology while drawing attention to relevant findings and highlight current limitations.
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Affiliation(s)
- Raquel Liébana
- a Division of Water Environment Technology, Department of Architecture and Civil Engineering , Chalmers University of Technology , Gothenburg , Sweden
| | - Oskar Modin
- a Division of Water Environment Technology, Department of Architecture and Civil Engineering , Chalmers University of Technology , Gothenburg , Sweden
| | - Frank Persson
- a Division of Water Environment Technology, Department of Architecture and Civil Engineering , Chalmers University of Technology , Gothenburg , Sweden
| | - Britt-Marie Wilén
- a Division of Water Environment Technology, Department of Architecture and Civil Engineering , Chalmers University of Technology , Gothenburg , Sweden
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26
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Szabó E, Liébana R, Hermansson M, Modin O, Persson F, Wilén BM. Comparison of the bacterial community composition in the granular and the suspended phase of sequencing batch reactors. AMB Express 2017; 7:168. [PMID: 28871435 PMCID: PMC5583138 DOI: 10.1186/s13568-017-0471-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Accepted: 08/30/2017] [Indexed: 11/10/2022] Open
Abstract
Granulation of activated sludge is an increasingly important area within the field of wastewater treatment. Granulation is usually achieved by high hydraulic selection pressure, which results in the wash-out of slow settling particles. The effect of the harsh wash-out conditions on the granular sludge ecosystem is not yet fully understood, but different bacterial groups may be affected to varying degrees. In this study, we used high-throughput amplicon sequencing to follow the community composition in granular sludge reactors for 12 weeks, both in the granular phase and the suspended phase (effluent). The microbiome of the washed out biomass was similar but not identical to the microbiome of the granular biomass. Certain taxa (e.g. Flavobacterium spp. and Bdellovibrio spp.) had significantly (p < 0.05) higher relative abundance in the granules compared to the effluent. Fluorescence in situ hybridization images indicated that these taxa were mainly located in the interior of granules and therefore protected from erosion. Other taxa (e.g. Meganema sp. and Zooglea sp.) had significantly lower relative abundance in the granules compared to the effluent, and appeared to be mainly located on the surface of granules and therefore subject to erosion. Despite being washed out, these taxa were among the most abundant members of the granular sludge communities and were likely growing fast in the reactors. The ratio between relative abundance in the granular biomass and in the effluent did not predict temporal variation of the taxa in the reactors, but it did appear to predict the spatial location of the taxa in the granules.
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28
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Szabó E, Liébana R, Hermansson M, Modin O, Persson F, Wilén BM. Microbial Population Dynamics and Ecosystem Functions of Anoxic/Aerobic Granular Sludge in Sequencing Batch Reactors Operated at Different Organic Loading Rates. Front Microbiol 2017; 8:770. [PMID: 28507540 PMCID: PMC5410608 DOI: 10.3389/fmicb.2017.00770] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Accepted: 04/13/2017] [Indexed: 11/13/2022] Open
Abstract
The granular sludge process is an effective, low-footprint alternative to conventional activated sludge wastewater treatment. The architecture of the microbial granules allows the co-existence of different functional groups, e.g., nitrifying and denitrifying communities, which permits compact reactor design. However, little is known about the factors influencing community assembly in granular sludge, such as the effects of reactor operation strategies and influent wastewater composition. Here, we analyze the development of the microbiomes in parallel laboratory-scale anoxic/aerobic granular sludge reactors operated at low (0.9 kg m-3d-1), moderate (1.9 kg m-3d-1) and high (3.7 kg m-3d-1) organic loading rates (OLRs) and the same ammonium loading rate (0.2 kg NH4-N m-3d-1) for 84 days. Complete removal of organic carbon and ammonium was achieved in all three reactors after start-up, while the nitrogen removal (denitrification) efficiency increased with the OLR: 0% at low, 38% at moderate, and 66% at high loading rate. The bacterial communities at different loading rates diverged rapidly after start-up and showed less than 50% similarity after 6 days, and below 40% similarity after 84 days. The three reactor microbiomes were dominated by different genera (mainly Meganema, Thauera, Paracoccus, and Zoogloea), but these genera have similar ecosystem functions of EPS production, denitrification and polyhydroxyalkanoate (PHA) storage. Many less abundant but persistent taxa were also detected within these functional groups. The bacterial communities were functionally redundant irrespective of the loading rate applied. At steady-state reactor operation, the identity of the core community members was rather stable, but their relative abundances changed considerably over time. Furthermore, nitrifying bacteria were low in relative abundance and diversity in all reactors, despite their large contribution to nitrogen turnover. The results suggest that the OLR has considerable impact on the composition of the granular sludge communities, but also that the granule communities can be dynamic even at steady-state reactor operation due to high functional redundancy of several key guilds. Knowledge about microbial diversity with specific functional guilds under different operating conditions can be important for engineers to predict the stability of reactor functions during the start-up and continued reactor operation.
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Affiliation(s)
- Enikö Szabó
- Division of Water Environment Technology, Department of Civil and Environmental Engineering, Chalmers University of TechnologyGothenburg, Sweden
| | - Raquel Liébana
- Division of Water Environment Technology, Department of Civil and Environmental Engineering, Chalmers University of TechnologyGothenburg, Sweden
| | - Malte Hermansson
- Department of Chemistry and Molecular Biology, University of GothenburgGothenburg, Sweden
| | - Oskar Modin
- Division of Water Environment Technology, Department of Civil and Environmental Engineering, Chalmers University of TechnologyGothenburg, Sweden
| | - Frank Persson
- Division of Water Environment Technology, Department of Civil and Environmental Engineering, Chalmers University of TechnologyGothenburg, Sweden
| | - Britt-Marie Wilén
- Division of Water Environment Technology, Department of Civil and Environmental Engineering, Chalmers University of TechnologyGothenburg, Sweden
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29
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Abstract
The activated sludge process is commonly used to treat wastewater by aerobic oxidation of organic pollutants into carbon dioxide and water. However, several nonoxidative mechanisms can also contribute to removal of organics. Sorption onto activated sludge can remove a large fraction of the colloidal and particulate wastewater organics. Intracellular storage of, e.g., polyhydroxyalkanoates (PHA), triacylglycerides (TAG), or wax esters can convert wastewater organics into precursors for high-value products. Recently, several environmental, economic, and technological drivers have stimulated research on nonoxidative removal of organics for wastewater treatment. In this paper, we review these nonoxidative removal mechanisms as well as the existing and emerging process configurations that make use of them for wastewater treatment. Better utilization of nonoxidative processes in activated sludge could reduce the wasteful aerobic oxidation of organic compounds and lead to more resource-efficient wastewater treatment plants.
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Affiliation(s)
- Oskar Modin
- Division of Water Environment Technology, Department of Civil and Environmental Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Frank Persson
- Division of Water Environment Technology, Department of Civil and Environmental Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Britt-Marie Wilén
- Division of Water Environment Technology, Department of Civil and Environmental Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Malte Hermansson
- Department of Chemistry and Molecular Biology, Gothenburg University, Gothenburg, Sweden
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Saheb Alam S, Persson F, Wilén BM, Hermansson M, Modin O. Effects of storage on mixed-culture biological electrodes. Sci Rep 2015; 5:18433. [PMID: 26678949 PMCID: PMC4683449 DOI: 10.1038/srep18433] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Accepted: 11/18/2015] [Indexed: 01/24/2023] Open
Abstract
Storage methods are important to preserve the viability and biochemical characteristics of microbial cultures between experiments or during periods when bioreactors are inactive. Most of the research on storage has focused on isolates; however, there is an increasing interest in methods for mixed cultures, which are of relevance in environmental biotechnology. The purpose of this study was to investigate the effect of different storage methods on electrochemically active enrichment cultures. Acetate-oxidizing bioanodes generating a current density of about 5 A m−2 were enriched in a microbial electrolysis cell. The effect of five weeks of storage was evaluated using electrochemical techniques and microbial community analysis. Storage by refrigeration resulted in quicker re-activation than freezing in 10% glycerol, while the bioelectrochemical activity was entirely lost after storage using dehydration. The results showed that the bioelectrochemical activity of bioanodes stored at low temperature could be retained. However, during the re-activation period the bioanodes only recovered 75% of the current density generated before storage and the bacterial communities were different in composition and more diverse after storage than before.
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Affiliation(s)
- Soroush Saheb Alam
- Division of Water Environment Technology, Department of Civil and Environmental Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Frank Persson
- Division of Water Environment Technology, Department of Civil and Environmental Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Britt-Marie Wilén
- Division of Water Environment Technology, Department of Civil and Environmental Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Malte Hermansson
- Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Oskar Modin
- Division of Water Environment Technology, Department of Civil and Environmental Engineering, Chalmers University of Technology, Gothenburg, Sweden
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31
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Modin O, Saheb Alam S, Persson F, Wilén BM. Sorption and release of organics by primary, anaerobic, and aerobic activated sludge mixed with raw municipal wastewater. PLoS One 2015; 10:e0119371. [PMID: 25768429 PMCID: PMC4359093 DOI: 10.1371/journal.pone.0119371] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Accepted: 01/13/2015] [Indexed: 11/18/2022] Open
Abstract
New activated sludge processes that utilize sorption as a major mechanism for organics removal are being developed to maximize energy recovery from wastewater organics, or as enhanced primary treatment technologies. To model and optimize sorption-based activated sludge processes, further knowledge about sorption of organics onto sludge is needed. This study compared primary-, anaerobic-, and aerobic activated sludge as sorbents, determined sorption capacity and kinetics, and investigated some characteristics of the organics being sorbed. Batch sorption assays were carried out without aeration at a mixing velocity of 200 rpm. Only aerobic activated sludge showed net sorption of organics. Sorption of dissolved organics occurred by a near-instantaneous sorption event followed by a slower process that obeyed 1st order kinetics. Sorption of particulates also followed 1st order kinetics but there was no instantaneous sorption event; instead there was a release of particles upon mixing. The 5-min sorption capacity of activated sludge was 6.5±10.8 mg total organic carbon (TOC) per g volatile suspend solids (VSS) for particulate organics and 5.0±4.7 mgTOC/gVSS for dissolved organics. The observed instantaneous sorption appeared to be mainly due to organics larger than 20 kDa in size being sorbed, although molecules with a size of about 200 Da with strong UV absorbance at 215–230 nm were also rapidly removed.
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Affiliation(s)
- Oskar Modin
- Division of Water Environment Technology, Department of Civil and Environmental Engineering, Chalmers University of Technology, Gothenburg, Sweden
- * E-mail:
| | - Soroush Saheb Alam
- Division of Water Environment Technology, Department of Civil and Environmental Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Frank Persson
- Division of Water Environment Technology, Department of Civil and Environmental Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Britt-Marie Wilén
- Division of Water Environment Technology, Department of Civil and Environmental Engineering, Chalmers University of Technology, Gothenburg, Sweden
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Abstract
Microbial bioelectrochemical systems (BESs) utilize living microorganisms to drive oxidation and reduction reactions at solid electrodes. BESs could potentially be used at municipal wastewater treatment plants (WWTPs) to recover the energy content of organic matter, to produce chemicals useful at the site, or to monitor and control biological treatment processes. In this paper, we review bioelectrochemical technologies that could be applied for municipal wastewater treatment. Sjölunda WWTP in Malmö, Sweden, is used as an example to illustrate how the different technologies potentially could be integrated into an existing treatment plant and the impact they could have on the plant's utilization of energy and chemicals.
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Affiliation(s)
- Oskar Modin
- Division of Water Environment Technology, Department of Civil and Environmental Engineering, Chalmers University of Technology, SE-412 96, Gothenburg, Sweden E-mail:
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Wu X, Modin O. Ammonium recovery from reject water combined with hydrogen production in a bioelectrochemical reactor. Bioresour Technol 2013; 146:530-536. [PMID: 23973971 DOI: 10.1016/j.biortech.2013.07.130] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2013] [Revised: 07/23/2013] [Accepted: 07/26/2013] [Indexed: 05/24/2023]
Abstract
In this study, a bioelectrochemical reactor was investigated for simultaneous hydrogen production and ammonium recovery from reject water, which is an ammonium-rich side-stream produced from sludge treatment processes at wastewater treatment plants. In the anode chamber of the reactor, microorganisms converted organic material into electrical current. The electrical current was used to generate hydrogen gas at the cathode with 96±6% efficiency. Real or synthetic reject water was fed to the cathode chamber where proton reduction into hydrogen gas resulted in a pH increase which led to ammonium being converted into volatile ammonia. The ammonia could be stripped from the solution and recovered in acid. Overall, ammonium recovery efficiencies reached 94% with synthetic reject water and 79% with real reject water. This process could potentially be used to make wastewater treatment plants more resource-efficient and further research is warranted.
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Affiliation(s)
- Xue Wu
- Division of Water Environment Technology, Civil and Environmental Engineering, Chalmers University of Technology, SE-41296 Gothenburg, Sweden.
| | - Oskar Modin
- Division of Water Environment Technology, Civil and Environmental Engineering, Chalmers University of Technology, SE-41296 Gothenburg, Sweden.
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34
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Abstract
Bioelectrochemical systems can be used to energy-efficiently produce hydrogen peroxide (H2O2) from wastewater. Organic compounds in the wastewater are oxidized by microorganisms using the anode as electron acceptor. H2O2 is produced by reduction of oxygen on the cathode. In this study, we demonstrate for the first time production of high concentrations of H2O2 production from real municipal wastewater. A concentration of 2.26 g/L H2O2 was produced in 9 h at 8.3 kWh/kgH2O2. This concentration could potentially be useful for membrane cleaning at membrane bioreactor wastewater treatment plants. With an acetate-containing nutrient medium as anode feed, a H2O2 concentration of 9.67 g/L was produced in 21 h at an energy cost of 3.0 kWh/kgH2O2. The bioelectrochemical reactor used in this study suffered from a high internal resistance, most likely caused by calcium carbonate deposits on the cathode-facing side of the cation exchange membrane separating the anode and cathode compartments.
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Affiliation(s)
- Oskar Modin
- Division of Water Environment Technology, Department of Civil & Environmental Engineering, Chalmers University of Technology, Gothenburg, Sweden.
| | - Kensuke Fukushi
- Integrated Research System for Sustainability Science (IR3S), The University of Tokyo, Tokyo, Japan
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35
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Modin O, Wilén BM. A novel bioelectrochemical BOD sensor operating with voltage input. Water Res 2012; 46:6113-6120. [PMID: 23021520 DOI: 10.1016/j.watres.2012.08.042] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2012] [Revised: 08/29/2012] [Accepted: 08/31/2012] [Indexed: 06/01/2023]
Abstract
Biochemical oxygen demand (BOD) is a measure of biodegradable compounds in water and is, for example, a common parameter to design and assess the performance of wastewater treatment plants. The conventional method to measure BOD is time consuming (5 or 7 days) and requires trained personnel. Bioelectrochemical BOD sensors designed as microbial fuel cells (MFCs), which are systems where bacteria convert organic matter into an electrical current, have emerged as an alternative to the conventional technique. In this study, a new type of bioelectrochemical BOD sensor with features that overcome some of the limitations of current MFC-type designs was developed: (1) An external voltage was applied to overcome internal resistances and allow bacteria to generate current at their full capacity, and (2) the ion exchange membrane was omitted to avoid pH shifts that would otherwise limit the applicability of the sensor for wastewaters with low alkalinity. The sensor was calibrated with an aerated nutrient medium containing acetate as the BOD source. Linear correlation (R(2) = 0.97) with charge was obtained for BOD concentrations ranging from 32 to 1280 mg/L in a reaction time of 20 h. Lowering the reaction time to 5 h resulted in lowering the measurable BOD concentration range to 320 mg/L (R(2) = 0.99). Propionate, glucose, and ethanol could also be analyzed by the sensor that was acclimated to acetate. The study demonstrates a way to design more robust and simple bioelectrochemical BOD sensors that do not suffer from the usual limitations of MFCs (high internal resistance and pH shifts).
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Affiliation(s)
- Oskar Modin
- Division of Water Environment Technology, Department of Civil and Environmental Engineering, Chalmers University of Technology, Sven Hultins gata 8, 41296 Gothenburg, Sweden.
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Modin O, Wang X, Wu X, Rauch S, Fedje KK. Bioelectrochemical recovery of Cu, Pb, Cd, and Zn from dilute solutions. J Hazard Mater 2012; 235-236:291-297. [PMID: 22910451 DOI: 10.1016/j.jhazmat.2012.07.058] [Citation(s) in RCA: 77] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Revised: 07/16/2012] [Accepted: 07/31/2012] [Indexed: 05/28/2023]
Abstract
In a microbial bioelectrochemical system (BES) living microorganisms catalyze the anodic oxidation of organic matter at a low anode potential. We used a BES with a biological anode to power the cathodic recovery of Cu, Pb, Cd, and Zn from a simulated municipal solid waste incineration ash leachate. By varying the control of the BES, the four metals could sequentially be recovered from a mixed solution by reduction on a titanium cathode. First, the cell voltage was controlled at zero, which allowed recovery of Cu from the solution without an electrical energy input. Second, the cathode potential was controlled at -0.51 V to recover Pb, which required an applied voltage of about 0.34 V. Third, the cathode potential was controlled at -0.66 V to recover Cd, which required an applied voltage of 0.51 V. Finally, Zn was the only metal remaining in solution and was recovered by controlling the anode at +0.2V to maximize the generated current. The study is the first to demonstrate that a BES can be used for cathodic recovery of metals from a mixed solution, which potentially could be used not only for ash leachates but also for e.g. metallurgical wastewaters and landfill leachates.
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Affiliation(s)
- Oskar Modin
- Division of Water Environment Technology, Department of Civil & Environmental Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden.
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Modin O, Fukushi K. Development and testing of bioelectrochemical reactors converting wastewater organics into hydrogen peroxide. Water Sci Technol 2012; 66:831-836. [PMID: 22766874 DOI: 10.2166/wst.2012.255] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
In a bioelectrochemical system, the energy content in dissolved organic matter can be used to power the production of hydrogen peroxide (H(2)O(2)), which is a potentially useful chemical at wastewater treatment plants. H(2)O(2) can be produced by the cathodic reduction of oxygen. We investigated four types of gas-diffusion electrodes (GDEs) for this purpose. A GDE made of carbon nanoparticles bound with 30% polytetrafluoroethylene (PTFE) (wt./wt.C) to a carbon fiber paper performed best and catalyzed H(2)O(2) production from oxygen in air with a coulombic efficiency of 95.1%. We coupled the GDE to biological anodes in two bioelectrochemical reactors. When the anodes were fed with synthetic wastewater containing acetate they generated a current of up to ∼0.4 mA/mL total anode compartment volume. H(2)O(2) concentrations of ∼0.2 and ∼0.5% could be produced in 5 mL catholyte in 9 and 21 h, respectively. When the anodes were fed with real wastewater, the generated current was ∼0.1 mA/mL and only 84 mg/L of H(2)O(2) was produced.
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Affiliation(s)
- Oskar Modin
- Department of Civil & Environmental Engineering, Chalmers University of Technology, Gothenburg, Sweden.
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38
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Modin O, Fukushi K, Rabaey K, Rozendal RA, Yamamoto K. Redistribution of wastewater alkalinity with a microbial fuel cell to support nitrification of reject water. Water Res 2011; 45:2691-2699. [PMID: 21421249 DOI: 10.1016/j.watres.2011.02.031] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2010] [Revised: 02/21/2011] [Accepted: 02/23/2011] [Indexed: 05/30/2023]
Abstract
In wastewater treatment plants, the reject water from the sludge treatment processes typically contains high ammonium concentrations, which constitute a significant internal nitrogen load in the plant. Often, a separate nitrification reactor is used to treat the reject water before it is fed back into the plant. The nitrification reaction consumes alkalinity, which has to be replenished by dosing e.g. NaOH or Ca(OH)(2). In this study, we investigated the use of a two-compartment microbial fuel cell (MFC) to redistribute alkalinity from influent wastewater to support nitrification of reject water. In an MFC, alkalinity is consumed in the anode compartment and produced in the cathode compartment. We use this phenomenon and the fact that the influent wastewater flow is many times larger than the reject water flow to transfer alkalinity from the influent wastewater to the reject water. In a laboratory-scale system, ammonium oxidation of synthetic reject water passed through the cathode chamber of an MFC, increased from 73.8 ± 8.9 mgN/L under open-circuit conditions to 160.1 ± 4.8 mgN/L when a current of 1.96 ± 0.37 mA (15.1 mA/L total MFC liquid volume) was flowing through the MFC. These results demonstrated the positive effect of an MFC on ammonium oxidation of alkalinity-limited reject water.
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Affiliation(s)
- Oskar Modin
- Integrated Research System for Sustainability Science, The University of Tokyo, 7-3-1, Hongo, Bunkyoku, Tokyo 113-8654, Japan.
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Modin O, Fukushi K, Nakajima F, Yamamoto K. Nitrate removal and biofilm characteristics in methanotrophic membrane biofilm reactors with various gas supply regimes. Water Res 2010; 44:85-96. [PMID: 19781736 DOI: 10.1016/j.watres.2009.09.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2009] [Revised: 08/31/2009] [Accepted: 09/01/2009] [Indexed: 05/28/2023]
Abstract
Aerobic methanotrophs can contribute to nitrate removal from contaminated waters, wastewaters, or landfill leachate by assimilatory reduction and by producing soluble organics that can be utilized by coexisting denitrifiers. The goal of this study was to investigate nitrate removal and biofilm characteristics in membrane biofilm reactors (MBfR) with various supply regimes of oxygen and methane gas. Three MBfR configurations were developed and they achieved significantly higher nitrate removal efficiencies in terms of methane utilization (values ranging from 0.25 to 0.36molNmol(-1)CH(4)) than have previously been observed with suspended cultures. The biofilm characteristics were investigated in two MBfRs with varying modes of oxygen supply. The biofilms differed in structure, but both were dominated by Type I methanotrophs growing close to the membrane surface. Detection of the nitrite reductase genes, nirS and nirK, suggested genetic potential for denitrification was present in the mixed culture biofilms.
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Affiliation(s)
- Oskar Modin
- Department of Urban Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
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Modin O, Fukushi K, Nakajima F, Yamamoto K. Performance of a membrane biofilm reactor for denitrification with methane. Bioresour Technol 2008; 99:8054-8060. [PMID: 18440803 DOI: 10.1016/j.biortech.2008.03.042] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2007] [Revised: 03/17/2008] [Accepted: 03/17/2008] [Indexed: 05/26/2023]
Abstract
In this study, a membrane biofilm reactor was investigated for aerobic methane oxidation coupled indirectly to denitrification, a process potentially useful for denitrification of nitrate-contaminated waters and wastewaters using methane as external electron donor. Methane and oxygen were supplied from the interior of a silicone tube to a biofilm growing on its surface. We found that the membrane biofilm reactor was to some extent self-regulating in the supply of methane and oxygen. Although the intramembrane partial pressures of methane and oxygen were varied, the oxygen-to-methane ratio penetrating the membrane tended towards 1.68. Both nitrate removal rate and dissolved organic carbon (DOC) production rate appeared to be positively correlated with intramembrane methane pressure. Based on measured nitrate removal rates, DOC production rates, and nitrate removal efficiency, the possibility of using this method for treatment of a hypothetical wastewater was evaluated.
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Affiliation(s)
- Oskar Modin
- Department of Urban Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
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Modin O, Fukushi K, Yamamoto K. Simultaneous removal of nitrate and pesticides from groundwater using a methane-fed membrane biofilm reactor. Water Sci Technol 2008; 58:1273-1279. [PMID: 18845866 DOI: 10.2166/wst.2008.481] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Nitrate and pesticide contaminated ground- and surface-waters have been found around the world as a result of the use of these compounds in agricultural activities. In this study we investigated a biological treatment method to simultaneously remove nitrate and pesticides from contaminated water. Methane was supplied as the sole source of carbon to the microbial culture. A methane-fed membrane biofilm reactor (M-MBfR) was developed in which the methane was supplied through hollow-fiber membranes to a biofilm growing on the membrane surface. A methane-oxidizing culture enriched from activated sludge was used as inoculum for the experiments. Removal of nitrate and the four pesticides atrazine, aldicarb, alachlor, and malathion was examined both in suspended culture and in the M-MBfR. The maximum denitrification rate with suspended culture was 36.8 mg N gVSS(-1) d(-1). With the M-MBfR setup, a hydraulic retention time of approximately one hour was required to completely remove an incoming nitrate concentration of about 20 mg NO3-N l(-1). The microbial culture could remove three of the pesticides (aldicarb, alachlor, and malathion). However, no atrazine removal was observed. The removal rates of both nitrate and pesticides were similar in suspended culture and in membrane-attached biofilm.
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Affiliation(s)
- O Modin
- Department of Urban Engineering, The University of Tokyo, Tokyo, Japan.
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Modin O, Fukushi K, Nakajima F, Yamamoto K. A membrane biofilm reactor achieves aerobic methane oxidation coupled to denitrification (AME-D) with high efficiency. Water Sci Technol 2008; 58:83-87. [PMID: 18653940 DOI: 10.2166/wst.2008.648] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Methane would potentially be an inexpensive, widely available electron donor for denitrification of wastewaters poor in organics. Currently, no methanotrophic microbe is known to denitrify. However, aerobic methane oxidation coupled to denitrification (AME-D) has been observed in several laboratory studies. In the AME-D process, aerobic methanotrophs oxidise methane and release organic metabolites and lysis products, which are used by coexisting denitrifiers as electron donors for denitrification. Due to the presence of oxygen, the denitrification efficiency in terms of methane-to-nitrate consumption is usually low. To improve this efficiency the use of a membrane biofilm reactor was investigated. The denitrification efficiency of an AME-D culture in (1) a suspended growth reactor, and (2) a membrane biofilm reactor was studied. The methane-to-nitrate consumption ratio for the suspended culture was 8.7. For the membrane-attached culture the ratio was 2.2. The results clearly indicated that the membrane-attached biofilm was superior to the suspended culture in terms of denitrification efficiency. This study showed that for practical application of the AME-D process, focus should be placed on development of a biofilm reactor.
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Affiliation(s)
- O Modin
- Department of Urban Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
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Modin O, Fukushi K, Yamamoto K. Denitrification with methane as external carbon source. Water Res 2007; 41:2726-38. [PMID: 17433401 DOI: 10.1016/j.watres.2007.02.053] [Citation(s) in RCA: 141] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2006] [Revised: 02/16/2007] [Accepted: 02/25/2007] [Indexed: 05/14/2023]
Abstract
Methane is a potentially inexpensive, widely available electron donor for biological denitrification of wastewater, landfill leachate or drinking water. Although no known methanotroph is able to denitrify, various consortia of microorganisms using methane as the sole carbon source carry out denitrification both aerobically and anaerobically. Aerobic methane-oxidation coupled to denitrification (AME-D) is accomplished by aerobic methanotrophs oxidizing methane and releasing soluble organics that are used by coexisting denitrifiers as electron donors for denitrification. This process has been observed in several laboratory studies. Anaerobic methane oxidation coupled to denitrification (ANME-D) was recently discovered and was found to be mediated by an association of an archaeon and bacteria. Methane oxidizing consortia of microorganisms have also been studied for simultaneous nitrification and denitrification (SND) of wastewater. This review focuses on the AME-D process, but also encompasses methane oxidation coupled to SND as well as ANME-D.
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Affiliation(s)
- Oskar Modin
- Department of Urban Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
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