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Paulinetti AP, Guerieri FF, Augusto IMG, Lazaro CZ, Albanez R, Lovato G, Ratusznei SM, Domingues Rodrigues JA. Thermophilic and mesophilic anaerobic digestion of soybean molasses: A performance vs. stability trade-off. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 370:122508. [PMID: 39366238 DOI: 10.1016/j.jenvman.2024.122508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Revised: 09/02/2024] [Accepted: 09/12/2024] [Indexed: 10/06/2024]
Abstract
One of the factors that has a direct impact on anaerobic digestion is the applied organic loading rate (OLRA). Increasing OLRA can boost methane production but can also cause process failure. As a result, establishing the appropriate OLRA for the procedure is critical. This study evaluated the effect of increasing the OLRA using soybean molasses in a thermophilic anaerobic reactor (R-Thermo), as well as the effect of feeding strategy and co-processing with okara. Furthermore, the performance versus stability trade-off between R-Thermo and mesophilic anaerobic digestion (R-Meso) was investigated. The increase of OLRA from 10 to 15 and 20 kg-COD/m³/d led to a decrease in COD removal efficiency (90, 86, and 75%), methane yield (12.0, 11.6, and 9.9 mol-CH4/kg-COD) and an increase in total volatile acids concentration (251, 456, and 1393 mg-HAc/L, respectively). At 15 kg-COD/m³/d, R-Meso performed similarly to R-Thermo, and at 20 kg-COD/m3/d, R-Meso outperformed (81% COD removal efficiency, 9.3 mol-CH4/kg-CODrem and 154.5 mol-CH4/m3/d). Temperature greatly influenced the distribution of metabolic pathways, as shown by thermodynamic and kinetic analyses, thus impacting bacterial diversity. At 55 °C, amongst the bacterial genera, Tepidiphilus stood out (>28.2%), followed by Acetomicrobium, Coprothermobacter and Candidatus_Caldatribacterium. The OLRA clearly impacted the archaeal community; Methanothermobacter (77.4%) was favored over Methanosarcina (14.8%). Under thermophilic temperature, it seems that syntrophic acetate oxidation (SAO) bacteria might have competed for substrate with acetoclastic methanogens, while in R-Meso microorganisms responsible for the initial steps of organic matter breakdown, such as members of the Firmicutes and Proteobacteria phyla (at least 67%), were dominant. In summary, R-Meso, characterized by a more uniform distribution of metabolic pathways, as well as a diverse and well-adapted microbial consortium, have exhibited enhanced stability and outperformed R-Thermo at high-loads.
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Affiliation(s)
- Ana Paula Paulinetti
- Department of Chemical Engineering, Mauá School of Engineering, Mauá Institute of Technology, Praça Mauá 1, Zip Code 09.580-900, São Caetano do Sul/SP, Brazil; Department of Environmental Engineering Sciences, School of Engineering of São Carlos, University of São Paulo, Av. Trabalhador São-Carlense, 400 - Zip Code 13.566-590, São Carlos/SP, Brazil
| | - Fernanda Furtunato Guerieri
- Department of Chemical Engineering, Mauá School of Engineering, Mauá Institute of Technology, Praça Mauá 1, Zip Code 09.580-900, São Caetano do Sul/SP, Brazil
| | - Isabela Mehi Gaspari Augusto
- Department of Chemical Engineering, Mauá School of Engineering, Mauá Institute of Technology, Praça Mauá 1, Zip Code 09.580-900, São Caetano do Sul/SP, Brazil; Department of Environmental Engineering Sciences, School of Engineering of São Carlos, University of São Paulo, Av. Trabalhador São-Carlense, 400 - Zip Code 13.566-590, São Carlos/SP, Brazil
| | - Carolina Zampol Lazaro
- Department of Microbiology, Infectiology and Immunology, University of Montreal, H3C 3J7, Montreal/Quebec, Canada
| | - Roberta Albanez
- Department of Chemical Engineering, Mauá School of Engineering, Mauá Institute of Technology, Praça Mauá 1, Zip Code 09.580-900, São Caetano do Sul/SP, Brazil
| | - Giovanna Lovato
- Department of Chemical Engineering, Mauá School of Engineering, Mauá Institute of Technology, Praça Mauá 1, Zip Code 09.580-900, São Caetano do Sul/SP, Brazil
| | - Suzana Maria Ratusznei
- Department of Chemical Engineering, Mauá School of Engineering, Mauá Institute of Technology, Praça Mauá 1, Zip Code 09.580-900, São Caetano do Sul/SP, Brazil.
| | - José Alberto Domingues Rodrigues
- Department of Chemical Engineering, Mauá School of Engineering, Mauá Institute of Technology, Praça Mauá 1, Zip Code 09.580-900, São Caetano do Sul/SP, Brazil
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Li W, Chen J, Pang L, Lu Y, Yang P. Dosage effect of micron zero-valent iron during thermophilic anaerobic digestion of waste activated sludge: Performance and functional community. ENVIRONMENTAL RESEARCH 2023; 237:116997. [PMID: 37634689 DOI: 10.1016/j.envres.2023.116997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 08/09/2023] [Accepted: 08/25/2023] [Indexed: 08/29/2023]
Abstract
This work examined the performance and microbial traits in a thermophilic anaerobic digestion (TAD) of waste activated sludge that was impacted by micron zero valent iron (mZVI). Results showed that methane production was promoted by 0.8, 11.9, and 12.0 times, respectively, when mZVI was at dosages of 25, 100, and 250 mg/g total solid (TS). Also, the consumption of volatile fatty acids was increased by mZVI at higher dosages (100 and 250 mg/g TS). Furthermore, 16S rRNA sequencing demonstrated that microbial community stabilized after day 18 regardless of the dosage of mZVI, and that different dosages of mZVI induced different shifts in the functional community of the archaea rather than the bacteria involved in TAD. As a result, mZVI at 100 mg/g TS could increase the relative abundance of archaeal genera Methanothermobacter the most, increasing by 22.8% at the end of TAD compared to CK. Besides, redundancy analysis revealed that the physicochemical properties explained 79.65% and 89.10% of the variations of bacterial and archaeal abundance, respectively. Also, the findings of the correlation analysis revealed that total dissolved iron, ferrous iron, pH, and ammonium nitrogen, may be the key divers of altering functional communities, particularly archaea. Moreover, mZVI at 100 and 250 mg/g TS boosted the metabolic pathways of environmental information processing (ABC transporters) in bacteria and carbon metabolism and methane metabolism for archaea, as well as relative abundances of enzymes and their activities involved in various methanogenic pathways. This study provides new perspectives on the application of mZVI in solid wastes treatments.
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Affiliation(s)
- Wenqian Li
- College of Architecture and Environment, Sichuan University, Chengdu, 610065, PR China
| | - Jianglin Chen
- College of Architecture and Environment, Sichuan University, Chengdu, 610065, PR China
| | - Lina Pang
- College of Architecture and Environment, Sichuan University, Chengdu, 610065, PR China.
| | - Yuanyuan Lu
- College of Architecture and Environment, Sichuan University, Chengdu, 610065, PR China
| | - Ping Yang
- College of Architecture and Environment, Sichuan University, Chengdu, 610065, PR China
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Otieno EO, Kiplimo R, Mutwiwa U. Optimization of anaerobic digestion parameters for biogas production from pineapple wastes co-digested with livestock wastes. Heliyon 2023; 9:e14041. [PMID: 36925513 PMCID: PMC10011201 DOI: 10.1016/j.heliyon.2023.e14041] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Revised: 02/18/2023] [Accepted: 02/20/2023] [Indexed: 03/03/2023] Open
Abstract
The demand for energy has been growing over the years to match development and population growth. The current sustainable development model advocates for the use of renewable (green) energy sources with an aim of lowering carbon emissions thereby mitigating the effects of climate change. A circular economy aspires to keep materials in use for as long as possible thus the reuse of agricultural waste especially in energy generation is a step in this direction. This study reports on the optimization of anaerobic digestion parameters for biogas production when wastes from pineapple are co-digested with those from livestock. The volume of biogas yield was optimized with regards to temperature, pH value, and mixing ratio of the substrates using Box Behnken Design (BBD), a class of Response Surface Methodology (RSM). This was achieved through a software package, Design Expert 13.The experiments were performed using Rehau home gas systems of 6 m3 in Jomo Kenyatta University of Agriculture and Technology. Pineapple wastes were co-digested with livestock waste in the ratio of 1:1, 1:2 and 1:3. The numerical optimization results revealed that the maximum biogas yield was 1.98 m3 when the pH was set at 6.0, temperature at 30 °C and pineapple mixing ratio at 62.5%. The results from this study can form a basis for policy makers in formulating strategies to guide adoption of biogas generated from agricultural waste as a key green energy for the economy.
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Affiliation(s)
- Edwin Ochieng Otieno
- Pan African University Institute for Basic Sciences, Technology and Innovation, P. O. Box 62000-00200, Nairobi, Kenya
| | - Robert Kiplimo
- Pan African University Institute for Basic Sciences, Technology and Innovation, P. O. Box 62000-00200, Nairobi, Kenya.,Department of Marine Engineering and Maritime Operation, Jomo Kenyatta University of Agriculture and Technology, P.O. Box 62000 - 00200, Nairobi, Kenya
| | - Urbanus Mutwiwa
- Agricultural and Biosystems Engineering Department, Jomo Kenyatta University of Agriculture and Technology, P.O. Box 62000 - 00200, Nairobi, Kenya
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A Review of Basic Bioinformatic Techniques for Microbial Community Analysis in an Anaerobic Digester. FERMENTATION-BASEL 2023. [DOI: 10.3390/fermentation9010062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Biogas production involves various types of intricate microbial populations in an anaerobic digester (AD). To understand the anaerobic digestion system better, a broad-based study must be conducted on the microbial population. Deep understanding of the complete metagenomics including microbial structure, functional gene form, similarity/differences, and relationships between metabolic pathways and product formation, could aid in optimization and enhancement of AD processes. With advancements in technologies for metagenomic sequencing, for example, next generation sequencing and high-throughput sequencing, have revolutionized the study of microbial dynamics in anaerobic digestion. This review includes a brief introduction to the basic process of metagenomics research and includes a detailed summary of the various bioinformatics approaches, viz., total investigation of data obtained from microbial communities using bioinformatics methods to expose metagenomics characterization. This includes (1) methods of DNA isolation and sequencing, (2) investigation of anaerobic microbial communities using bioinformatics techniques, (3) application of the analysis of anaerobic microbial community and biogas production, and (4) restriction and prediction of bioinformatics analysis on microbial metagenomics. The review has been concluded, giving a summarized insight into bioinformatic tools and also promoting the future prospects of integrating humungous data with artificial intelligence and neural network software.
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Li C, Hao L, Lü F, Duan H, Zhang H, He P. Syntrophic Acetate-Oxidizing Microbial Consortia Enriched from Full-Scale Mesophilic Food Waste Anaerobic Digesters Showing High Biodiversity and Functional Redundancy. mSystems 2022; 7:e0033922. [PMID: 36073802 PMCID: PMC9600251 DOI: 10.1128/msystems.00339-22] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 08/15/2022] [Indexed: 12/24/2022] Open
Abstract
Syntrophic acetate oxidation (SAO) coupled with hydrogenotrophic methanogenesis (HM) plays a vital role in the anaerobic digestion of protein-rich feedstocks such as food wastes. However, current knowledge of the biodiversity and genetic potential of the involved microbial participants, especially syntrophic acetate-oxidizing bacteria (SAOB), is limited due to the low abundance of these microorganisms and challenges in their isolation. The intent of this study was to enrich and identify potential SAOB. Therefore, we conducted continuous acetate feeding under high ammonia concentrations using two separate inoculum consortia of microorganisms that originated from full-scale mesophilic food waste digesters, which lasted for more than 200 days. Using 16S rRNA gene amplicon and metagenomic analyses, we observed a convergence of the experimental microbial communities during the enrichment regarding taxonomic composition and metabolic functional composition. Stable carbon isotope analyses of biogas indicated that SAO-HM was the dominant methanogenic pathway during the enrichment process. The hydrogenotrophic methanogen Methanoculleus dominated the archaeal community. The enriched SAO community featured high biodiversity and metabolic functional redundancy. By analyzing the metagenome-assembled genomes, the known SAOB Syntrophaceticus schinkii and six uncultured populations were identified to have the genetic potential to perform SAO through the conventional reversed Wood-Ljungdahl pathway, while another six bacteria were found to encode the reversed Wood-Ljungdahl pathway combined with a glycine cleavage system as novel SAOB candidates. These results showed that the food waste anaerobic digesters harbor diverse SAOB and highlighted the importance of the glycine cleavage system for acetate oxidation. IMPORTANCE Syntrophic acetate oxidation to CO2 and H2, together with hydrogenotrophic methanogenesis, contributes to much of the carbon flux in the anaerobic digestion of organic wastes, especially at high ammonia concentrations. A deep understanding of the biodiversity, metabolic genetic potential, and ecology of the SAO community can help to improve biomethane production from wastes for clean energy production. Here, we enriched the SAO-HM functional guild obtained from full-scale food waste anaerobic digesters and recorded dynamic changes in community taxonomic composition and functional profiles. By reconstructing the metabolic pathways, diverse known and novel bacterial members were found to have SAO potential via the reversed Wood-Ljungdahl (WL) pathway alone, or via the reversed WL pathway with a glycine cleavage system (WLP-GCS), and those catalyzing WLP-GCS showed higher microbial abundance. This study revealed the biodiversity and metabolic functional redundancy of SAOB in full-scale anaerobic digester systems and provided inspiration for further genome-centric studies.
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Affiliation(s)
- Chao Li
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai, People’s Republic of China
| | - Liping Hao
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, People’s Republic of China
| | - Fan Lü
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai, People’s Republic of China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai, People’s Republic of China
| | - Haowen Duan
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai, People’s Republic of China
| | - Hua Zhang
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai, People’s Republic of China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai, People’s Republic of China
| | - Pinjing He
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai, People’s Republic of China
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Perez-Esteban N, Vinardell S, Vidal-Antich C, Peña-Picola S, Chimenos JM, Peces M, Dosta J, Astals S. Potential of anaerobic co-fermentation in wastewater treatments plants: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 813:152498. [PMID: 34968594 DOI: 10.1016/j.scitotenv.2021.152498] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 12/13/2021] [Accepted: 12/13/2021] [Indexed: 05/25/2023]
Abstract
Fermentation (not anaerobic digestion) is an emerging biotechnology to transform waste into easily assimilable organic compounds such as volatile fatty acids, lactic acid and alcohols. Co-fermentation, the simultaneous fermentation of two or more waste, is an opportunity for wastewater treatment plants (WWTPs) to increase the yields of sludge mono-fermentation. Most publications have studied waste activated sludge co-fermentation with food waste or agri-industrial waste. Mixing ratio, pH and temperature are the most studied variables. The highest fermentation yields have been generally achieved in mixtures dominated by the most biodegradable substrate at circumneutral pH and mesophilic conditions. Nonetheless, most experiments have been performed in batch assays which results are driven by the capabilities of the starting microbial community and do not allow evaluating the microbial acclimation that occurs under continuous conditions. Temperature, pH, hydraulic retention time and organic load are variables that can be controlled to optimise the performance of continuous co-fermenters (i.e., favour waste hydrolysis and fermentation and limit the proliferation of methanogens). This review also discusses the integration of co-fermentation with other biotechnologies in WWTPs. Overall, this review presents a comprehensive and critical review of the achievements on co-fermentation research and lays the foundation for future research.
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Affiliation(s)
- N Perez-Esteban
- Department of Chemical Engineering and Analytical Chemistry, University of Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain
| | - S Vinardell
- Department of Chemical Engineering and Analytical Chemistry, University of Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain
| | - C Vidal-Antich
- Department of Chemical Engineering and Analytical Chemistry, University of Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain; Water Research Institute, University of Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain
| | - S Peña-Picola
- Department of Chemical Engineering and Analytical Chemistry, University of Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain
| | - J M Chimenos
- Department of Materials Science and Physical Chemistry, University of Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain
| | - M Peces
- Department of Chemistry and Bioscience, Centre for Microbial Communities, Aalborg University, Fredrik Bajers Vej 7H, 9220 Aalborg, Denmark
| | - J Dosta
- Department of Chemical Engineering and Analytical Chemistry, University of Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain; Water Research Institute, University of Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain
| | - S Astals
- Department of Chemical Engineering and Analytical Chemistry, University of Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain.
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Moerland MJ, Castañares Pérez L, Ruiz Velasco Sobrino ME, Chatzopoulos P, Meulman B, de Wilde V, Zeeman G, Buisman CJN, van Eekert MHA. Thermophilic (55 °C) and hyper-thermophilic (70 °C) anaerobic digestion as novel treatment technologies for concentrated black water. BIORESOURCE TECHNOLOGY 2021; 340:125705. [PMID: 34391186 DOI: 10.1016/j.biortech.2021.125705] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 07/27/2021] [Accepted: 07/28/2021] [Indexed: 06/13/2023]
Abstract
Thermophilic and hyper-thermophilic anaerobic digestion (AD) are promising techniques for the treatment of concentrated black water (toilet fraction of domestic wastewater collected by low flush volume toilets; BW), recovery of nutrients and simultaneous pathogen removal for safe recovery and reuse of those nutrients. This study showed that thermophilic AD (55 °C) of concentrated BW reaches the same methanisation and COD removal as mesophilic anaerobic treatment of BW (conventional vacuum toilets) and kitchen waste while applying a higher loading rate (OLR) (2.5-4.0 kgCOD/m3/day). With a retention time of 8.7 days, and an OLR of >3 kgCOD/m3/day, COD removal of 70% and a methanisation of 62% (based on CODt) was achieved during thermophilic AD. Hyper-thermophilic (70 °C) reached lower levels of methanisation (38%). Start-up time of thermophilic AD was 12 days. And during thermophilic AD, a shift from acetoclastic methanogenesis towards syntrophic acetate oxidation was observed.
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Affiliation(s)
- Marinus J Moerland
- Department of Environmental Technology, Wageningen University and Research, Bornse Weilanden 9, 6706 WG Wageningen, the Netherlands.
| | - Laura Castañares Pérez
- Department of Environmental Technology, Wageningen University and Research, Bornse Weilanden 9, 6706 WG Wageningen, the Netherlands.
| | - Maria E Ruiz Velasco Sobrino
- Department of Environmental Technology, Wageningen University and Research, Bornse Weilanden 9, 6706 WG Wageningen, the Netherlands.
| | | | - Brendo Meulman
- DeSaH B.V, Pieter Zeemanstraat 6, 8606 JR Sneek, the Netherlands.
| | - Vinnie de Wilde
- Department of Environmental Technology, Wageningen University and Research, Bornse Weilanden 9, 6706 WG Wageningen, the Netherlands.
| | - Grietje Zeeman
- LeAF B.V, Bornse Weilanden 9, 6706 WG Wageningen, the Netherlands.
| | - Cees J N Buisman
- Department of Environmental Technology, Wageningen University and Research, Bornse Weilanden 9, 6706 WG Wageningen, the Netherlands.
| | - Miriam H A van Eekert
- Department of Environmental Technology, Wageningen University and Research, Bornse Weilanden 9, 6706 WG Wageningen, the Netherlands.
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Hao L, Fan L, Chapleur O, Guenne A, Bize A, Bureau C, Lü F, He P, Bouchez T, Mazéas L. Gradual development of ammonia-induced syntrophic acetate-oxidizing activities under mesophilic and thermophilic conditions quantitatively tracked using multiple isotopic approaches. WATER RESEARCH 2021; 204:117586. [PMID: 34474248 DOI: 10.1016/j.watres.2021.117586] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 08/13/2021] [Accepted: 08/17/2021] [Indexed: 06/13/2023]
Abstract
Insights into microbiota adaptation to increased ammonia stress, and identification of indicator microorganisms can help to optimize the operation of anaerobic digesters. To identify microbial indicators and investigate their metabolic contribution to acetoclastic methanogenesis (AM), syntrophic acetate oxidation (SAO) or hydrogenotrophic methanogenesis (HM), 40 anaerobic batch reactors fed with acetate of 110 mmol/L were set up at NH4+-N concentrations of 0.14 g/L, 5.00 g/L or 7.00 g/L, inoculated with thermophilic or mesophilic microbiota with or without pre-exposure to ammonia stress. Four stable carbon isotope probing approaches were applied in parallel, with [1,2-13C]-CH3COOH, [2-13C]-CH3COOH, [13C]NaHCO3 or non-labeled CH3COOH used individually. The last three approaches were used to quantify the methanogenic pathways by tracking labeled 13C or natural 13C signatures in the resulting CH4 and CO2, and consistently detected the dynamic transition of dominant pathways from AM to SAO-HM under ammonia stress. Results of quantitative PCR and fluorescence in-situ hybridization illustrated the procedure, acetotrophic methanogens being outcompeted by acetate-oxidizing syntrophs. The first and last isotope-labeling approaches were designed to probe the active acetate-mineralizing microbes with DNA-SIP. Known acetate-oxidizing bacteria like Syntrophaceticus and Tepidanaerobacter, as well as novel members of Pseudomonas, Bacillus and Symbiobacteraceae were detected, with Methanoculleus as the predominant H2/CO2-utilizing partner. Using NanoSIMS, some bacterial cells were observed to be fixing CO2 from [13C]NaHCO3. In this study, Methanosaeta was only active with ammonia < 200 mg-N/L; the syntrophs catalyzing SAO-HM started to compete with AM-conducting Methanosarcina at intermediate concentrations of ammonia, i.e. 200-500 mg-N/L, and outcompeted the acetotrophic methanogens with ammonia > 500 mg-N/L. Under ammonia stress, diverse known and novel microbial taxa were involved in acetate mineralization, comparable with those identified in previous studies.
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Affiliation(s)
- Liping Hao
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
| | - Lu Fan
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
| | - Olivier Chapleur
- Université Paris-Saclay, INRAE, PRocédés biOtechnologiques au Service de l'Environnement, Antony 92761, France
| | - Angéline Guenne
- Université Paris-Saclay, INRAE, PRocédés biOtechnologiques au Service de l'Environnement, Antony 92761, France
| | - Ariane Bize
- Université Paris-Saclay, INRAE, PRocédés biOtechnologiques au Service de l'Environnement, Antony 92761, France
| | - Chrystelle Bureau
- Université Paris-Saclay, INRAE, PRocédés biOtechnologiques au Service de l'Environnement, Antony 92761, France
| | - Fan Lü
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, China
| | - Pinjing He
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, China.
| | - Théodore Bouchez
- Université Paris-Saclay, INRAE, PRocédés biOtechnologiques au Service de l'Environnement, Antony 92761, France.
| | - Laurent Mazéas
- Université Paris-Saclay, INRAE, PRocédés biOtechnologiques au Service de l'Environnement, Antony 92761, France.
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Silva JAD, F M Braga A, Fermoso FG, Zaiat M, Silva GHR. Evaluation of the influence of trace metals on methane production from domestic sewage, using the Plackett-Burman experimental design. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 294:113002. [PMID: 34146930 DOI: 10.1016/j.jenvman.2021.113002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2020] [Revised: 05/17/2021] [Accepted: 06/02/2021] [Indexed: 06/12/2023]
Abstract
Methanogenesis involves several enzymes with trace metal components that catalyze major metabolic pathways and, therefore, requires a sufficient supply of micronutrients such as iron, nickel or cobalt. The statistically-based Plackett-Burman experimental design was adopted in this study to identify which trace metal have a statistically significant effect on the maximum methane production from domestic sewage. The addition of Barium (Ba), Cobalt (Co), Copper (Cu), Iron (Fe), Manganese (Mn), Nickel (Ni) and Selenium (Se) was tested in batch reactors using domestic sewage as the substrate and sewage sludge as the inoculum. The results showed that the addition of Fe was statistically significant, positively affecting the maximum CH4 production (p-value 0.05). The results are expressed in L of CH4 per g of Chemical Oxygen Demand added, increasing it from 0.10 to 0.13 LCH4 gCODadd-1. In L of CH4 per g of Volatile Solids, increased it from 0.031 to 0.040 LCH4 gVS-1. The addition of Se was statistically significant, but with a negative effect on the maximum methane production (p-value 0.002), which decreased from 0.13 to 0.10 LCH4.gCODadd-1. Moreover, six different Fe concentrations (0, 40, 80, 120, 160 and 200 mgL-1) were tested, showing that the addition of 120 mgL-1 had the greatest effect for statistically improving the maximum methane production, with 33% improvement (0.12 ± 0.003 to 0.16 ± 0.012 LCH4 gCODadd-1) compared to no addition of Fe and the specific CH4 production to 0.040 ± 0.001 LCH4 gVS-1.
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Affiliation(s)
- Julliana Alves da Silva
- Department of Civil and Environmental Engineering, São Paulo State University (UNESP), Av. Engenheiro Luiz Edmundo Carrijo Coube, 14-01, Vargem Limpa, 17033-360, Bauru, SP, Brazil.
| | - Adriana F M Braga
- Biological Processes Laboratory, Center for Research, Development and Innovation in Environmental Engineering, São Carlos School of Engineering (EESC), University of São Paulo (USP), Engenharia Ambiental - Bloco 4-F, Av. João Dagnone, 1100, Santa Angelina, 13.563-120, São Carlos, SP, Brazil.
| | - Fernando G Fermoso
- Instituto de laGrasa (C.S.I.C.), Campus Universitario Pablo de Olavide, Edificio 46, Ctra. de Utrera, km. 1 - 41013, Sevilla, Spain.
| | - Marcelo Zaiat
- Biological Processes Laboratory, Center for Research, Development and Innovation in Environmental Engineering, São Carlos School of Engineering (EESC), University of São Paulo (USP), Engenharia Ambiental - Bloco 4-F, Av. João Dagnone, 1100, Santa Angelina, 13.563-120, São Carlos, SP, Brazil.
| | - Gustavo H R Silva
- Department of Civil and Environmental Engineering, São Paulo State University (UNESP), Av. Engenheiro Luiz Edmundo Carrijo Coube, 14-01, Vargem Limpa, 17033-360, Bauru, SP, Brazil.
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10
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Wang M, Chen H, Chang S. Linkage among the combined temperature-retention time condition, microbial interaction, community structure, and process performance in the hydrolysis of waste activated sludge. BIORESOURCE TECHNOLOGY 2021; 331:125029. [PMID: 33831728 DOI: 10.1016/j.biortech.2021.125029] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Revised: 03/15/2021] [Accepted: 03/17/2021] [Indexed: 06/12/2023]
Abstract
Numerous studies have revealed the effect of temperature and hydraulic retention time (HRT) on microbiota in sludge biological hydrolysis (BH). However, few scholars have explored the combined effect of these two critical BH parameters. This study explored the BH performance and community structures over 12 combined temperatures-HRT conditions for temperatures from 35 °C to 55 °C and HRTs from 1.5 days to 6.0 days. Results showed that the 12 combined conditions formed only six distinct community structures with each of them relating to a distinctive range of volatile suspended solid reduction rates. The nonmetric multidimensional scaling and species-species association analysis on the DNA sequencing data revealed that the community structure was greatly driven by the microbial interactions (e.g., heterogeneous commensalism and competition) under the effect of temperature and HRT. This study established the linkages among the combined BH temperature-HRT conditions, microbial interaction, microbial community, and BH performance.
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Affiliation(s)
- Meiying Wang
- School of Engineering, University of Guelph, Ontario N1G 2W1, Canada.
| | - Huibin Chen
- School of Engineering, University of Guelph, Ontario N1G 2W1, Canada; College of Life Sciences, Fujian Normal University, Fuzhou 350117, China.
| | - Sheng Chang
- School of Engineering, University of Guelph, Ontario N1G 2W1, Canada.
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11
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Chen G, Wu W, Xu J, Wang Z. An anaerobic dynamic membrane bioreactor for enhancing sludge digestion: Impact of solids retention time on digestion efficacy. BIORESOURCE TECHNOLOGY 2021; 329:124864. [PMID: 33631451 DOI: 10.1016/j.biortech.2021.124864] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 02/10/2021] [Accepted: 02/11/2021] [Indexed: 06/12/2023]
Abstract
An anaerobic dynamic membrane bioreactor (AnDMBR), which enabled the decoupling of hydraulic retention time (HRT) and solids retention time (SRT), was used for enhancing sludge digestion, with the associated mechanisms elucidated. With the increase of SRT, the biogas production and sludge reduction rate were both enhanced. The specific biogas production and volatile solids (VS) reduction rate were improved to 0.79 L/g VS and 55.9% under SRT 50 d, respectively. Microbial community analysis revealed that Chloroflexi, which is capable of degrading metabolites and dead cells, was enriched at longer SRT. Further analysis showed that both acetoclastic and hydrogenotrophic methanogenesis contributed to the enhanced biogas production under higher SRT compared to the dominance of acetoclastic methanogenesis under lower SRT. The enhanced utilization of organic matter and acetate at longer SRT further confirmed the mechanisms. The results highlighted the potential of AnDMBR for high-efficient sludge digestion.
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Affiliation(s)
- Guang Chen
- State Key Laboratory of Pollution Control and Resource Reuse, Shanghai Institute of Pollution Control and Ecological Security, School and Environment of Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Chengtou Wastewater Treatment Co., Ltd., Shanghai 201203, China
| | - Wei Wu
- State Key Laboratory of Pollution Control and Resource Reuse, Shanghai Institute of Pollution Control and Ecological Security, School and Environment of Science and Engineering, Tongji University, Shanghai 200092, China
| | - Jun Xu
- State Key Laboratory of Pollution Control and Resource Reuse, Shanghai Institute of Pollution Control and Ecological Security, School and Environment of Science and Engineering, Tongji University, Shanghai 200092, China
| | - Zhiwei Wang
- State Key Laboratory of Pollution Control and Resource Reuse, Shanghai Institute of Pollution Control and Ecological Security, School and Environment of Science and Engineering, Tongji University, Shanghai 200092, China.
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12
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Huang J, Zhao Y, Lei C, Liu Y, Wang Y. The effect of reduced pressure and glucose concentration on hydrogen and volatile fatty acid yield: The role of homoacetogenesis. BIORESOURCE TECHNOLOGY 2021; 329:124830. [PMID: 33639380 DOI: 10.1016/j.biortech.2021.124830] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 02/03/2021] [Accepted: 02/04/2021] [Indexed: 06/12/2023]
Abstract
In this study, the influence of headspace pressure (HP; 20-100 kPa) and organic loading rate (OLR; 10-30 g/L) on H2 and volatile fatty acid (VFA) yield were investigated. The experiments were carried out in the semi-continuous mode, the main products in VFAs were ethanol and butyrate, which accounted for more than 75%. More than 79% generated H2 was consumed through homoacetogenesis pathway when HP was 100 kPa, and lowing HP could effectively promote the accumulation of H2 (increased by at least 2 times). Even though consumed H2 through homoacetogenesis was related to OLR and HP, the lower HP was more likely to reduce this part H2 consumption, especially under 10 g/L condition. As for acid production rate, both OLR and HP have a significant effect (p < 0.05). Maximum acid production rate was 489.86 mg-COD/g-CODdegrade·d-1when OLR was 20 g/L and HP was 40 kPa.
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Affiliation(s)
- Jialong Huang
- College of Engineering, Huazhong Agricultural University, Wuhan 430070, PR China; Key Laboratory of Agricultural Equipment in Mid-lower Yangtze River, PR China
| | - Yongkun Zhao
- College of Engineering, Huazhong Agricultural University, Wuhan 430070, PR China; Key Laboratory of Agricultural Equipment in Mid-lower Yangtze River, PR China
| | - Chen'ao Lei
- College of Engineering, Huazhong Agricultural University, Wuhan 430070, PR China; Key Laboratory of Agricultural Equipment in Mid-lower Yangtze River, PR China
| | - Yu Liu
- College of Engineering, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Yuanyuan Wang
- College of Engineering, Huazhong Agricultural University, Wuhan 430070, PR China; Key Laboratory of Agricultural Equipment in Mid-lower Yangtze River, PR China.
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13
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Jiang C, Peces M, Andersen MH, Kucheryavskiy S, Nierychlo M, Yashiro E, Andersen KS, Kirkegaard RH, Hao L, Høgh J, Hansen AA, Dueholm MS, Nielsen PH. Characterizing the growing microorganisms at species level in 46 anaerobic digesters at Danish wastewater treatment plants: A six-year survey on microbial community structure and key drivers. WATER RESEARCH 2021; 193:116871. [PMID: 33578056 DOI: 10.1016/j.watres.2021.116871] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 01/11/2021] [Accepted: 01/21/2021] [Indexed: 06/12/2023]
Abstract
Anaerobic digestion (AD) is a key technology at many wastewater treatment plants (WWTPs) for converting primary and surplus activated sludge to methane-rich biogas. However, the limited number of surveys and the lack of comprehensive datasets have hindered a deeper understanding of the characteristics and associations between key variables and the microbial community composition. Here, we present a six-year survey of 46 anaerobic digesters, located at 22 WWTPs in Denmark, which is the first and largest known study of the microbial ecology of AD at WWTPs at a regional scale. For three types of AD (mesophilic, mesophilic with thermal hydrolysis pretreatment, and thermophilic), we present the typical value range of 12 key parameters including operational variables and performance parameters. High-resolution bacterial and archaeal community analyses were carried out at species level using amplicon sequencing of >1,000 samples and the new ecosystem-specific MiDAS 3 reference database. We detected 42 phyla, 1,600 genera, and 3,584 species in the bacterial community, where 70% of the genera and 93% of the species represented environmental taxa that were only classified based on MiDAS 3 de novo placeholder taxonomy. More than 40% of the bacterial species were found not to grow in the mesophilic and thermophilic digesters and were only present due to immigration with the feed sludge. Ammonium concentration was the main driver shaping the bacterial community while temperature and pH were main drivers for the archaea in the three types of ADs. Sub-setting for the growing microbes improved significantly the correlation analyses and revealed the main drivers for the presence of specific species. Within mesophilic digesters, feed sludge composition and other key parameters (organic loading rate, biogas yield, and ammonium concentration) correlated with specific growing species. This survey provides a comprehensive insight into community structure at species level, providing a foundation for future studies of the ecological significance/characteristics and function of the many novel or poorly described taxa.
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Affiliation(s)
- Chenjing Jiang
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark; Key Laboratory of Engineering Oceanography, Second Institute of Oceanography, SOA, Hangzhou, China
| | - Miriam Peces
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Martin Hjorth Andersen
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Sergey Kucheryavskiy
- Section of Chemical Engineering, Department of Chemistry and Bioscience, Aalborg University, Esbjerg, Denmark
| | - Marta Nierychlo
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Erika Yashiro
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Kasper Skytte Andersen
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Rasmus Hansen Kirkegaard
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Liping Hao
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | | | | | - Morten Simonsen Dueholm
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Per Halkjær Nielsen
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark.
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14
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Zakaria BS, Ranjan Dhar B. An intermittent power supply scheme to minimize electrical energy input in a microbial electrolysis cell assisted anaerobic digester. BIORESOURCE TECHNOLOGY 2021; 319:124109. [PMID: 33035866 DOI: 10.1016/j.biortech.2020.124109] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 09/04/2020] [Accepted: 09/07/2020] [Indexed: 06/11/2023]
Abstract
From the perspective of energy saving in the operation of microbial electrolysis cell assisted anaerobic digester (MEC-AD), this study focused on developing an intermittent power supply scheme. The applied potential was switched off for 12 and 6 hours/day during the operation of a laboratory-scale MEC-AD system fed with glucose. The results from the operation under continuous applied potential served as the control. The overall biomethane generation and net energy income from the process were unaffected when the applied potential turned off for 6 hours/day. Both quantitative and qualitative analyses of microbial communities suggested that a balanced microbiome could be maintained under short-term switching-off the applied potential. However, performance substantially deteriorated when the applied potential turned off for 12 hours/day. Overall, the results of this study suggest that MEC-AD operation does not need a continuous power supply, and higher energy efficiency can be effectively achieved by intermittently powering the reactor.
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Affiliation(s)
- Basem S Zakaria
- Civil and Environmental Engineering, University of Alberta, 9211-116 Street NW, Edmonton, AB T6G 1H9, Canada
| | - Bipro Ranjan Dhar
- Civil and Environmental Engineering, University of Alberta, 9211-116 Street NW, Edmonton, AB T6G 1H9, Canada.
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15
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Shen R, Jing Y, Feng J, Zhao L, Yao Z, Yu J, Chen J, Chen R. Simultaneous carbon dioxide reduction and enhancement of methane production in biogas via anaerobic digestion of cornstalk in continuous stirred-tank reactors: The influences of biochar, environmental parameters, and microorganisms. BIORESOURCE TECHNOLOGY 2021; 319:124146. [PMID: 32977099 DOI: 10.1016/j.biortech.2020.124146] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 09/12/2020] [Accepted: 09/14/2020] [Indexed: 06/11/2023]
Abstract
The composition of biogas produced by anaerobic digestion (AD) is typically not ideal due to high CO2 content. In the study, cottonwood biochar was used as an enhanced mediator for the continuously stirred tank reactor AD of cornstalk. The effects of substrate loading and biochar dosage on biogas composition, volatile fatty acids (VFAs), NH3-N, and microbial community characteristics were systematically explored. The results showed that the highest volumetric biogas production rate with biochar was 1.40 L/L/d, at the same time, the CO2 content in the biogas decreased by 5.90%, while the CH4 content increased by 7.40%, compared with the values in AD without biochar. Moreover, VFAs were degraded effectively, in particular, the propionic acid concentration decreased by 55.7%. Besides, microbial abundance had positive correlations with environmental parameters. This study could provide valuable information for both the elucidation of strengthening mechanisms of biochar and further large-scale engineering application.
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Affiliation(s)
- Ruixia Shen
- Academy of Agricultural Planning and Engineering, Key Laboratory of Energy Resource Utilization from Agriculture Residue, Ministry of Agriculture, Beijing 100125, China
| | - Yong Jing
- Academy of Agricultural Planning and Engineering, Key Laboratory of Energy Resource Utilization from Agriculture Residue, Ministry of Agriculture, Beijing 100125, China
| | - Jing Feng
- Academy of Agricultural Planning and Engineering, Key Laboratory of Energy Resource Utilization from Agriculture Residue, Ministry of Agriculture, Beijing 100125, China
| | - Lixin Zhao
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Zonglu Yao
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Jiadong Yu
- Academy of Agricultural Planning and Engineering, Key Laboratory of Energy Resource Utilization from Agriculture Residue, Ministry of Agriculture, Beijing 100125, China
| | - Jiankun Chen
- Academy of Agricultural Planning and Engineering, Key Laboratory of Energy Resource Utilization from Agriculture Residue, Ministry of Agriculture, Beijing 100125, China
| | - Runlu Chen
- Academy of Agricultural Planning and Engineering, Key Laboratory of Energy Resource Utilization from Agriculture Residue, Ministry of Agriculture, Beijing 100125, China
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16
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Thermophilic Anaerobic Digestion of Second Cheese Whey: Microbial Community Response to H2 Addition in a Partially Immobilized Anaerobic Hybrid Reactor. Processes (Basel) 2020. [DOI: 10.3390/pr9010043] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
In this study, we investigated thermophilic (55 °C) anaerobic digestion (AD) performance and microbial community structure, before and after hydrogen addition, in a novel hybrid gas-stirred tank reactor (GSTR) implemented with a partial immobilization of the microbial community and fed with second cheese whey (SCW). The results showed that H2 addition led to a 25% increase in the methane production rate and to a decrease of 13% in the CH4 concentration as compared with the control. The recovery of methane content (56%) was reached by decreasing the H2 flow rate. The microbial community investigations were performed on effluent (EF) and on interstitial matrix (IM) inside the immobilized area. Before H2 addition, the Anaerobaculaceae (42%) and Lachnospiraceae (27%) families dominated among bacteria in the effluent, and the Thermodesulfobiaceae (32%) and Lachnospiraceae (30%) families dominated in the interstitial matrix. After H2 addition, microbial abundance showed an increase in the bacteria and archaea communities in the interstitial matrix. The Thermodesulfobiaceae family (29%)remained dominant in the interstitial matrix, suggesting its crucial role in the immobilized community and the SHA-31 family was enriched in both the effluent (36%) and the interstitial matrix (15%). The predominance of archaea Methanothermobacter thermoautrophicus indicated that CH4 was produced almost exclusively by the hydrogenotrophic pathway.
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17
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Zhang L, Guo B, Mou A, Li R, Liu Y. Blackwater biomethane recovery using a thermophilic upflow anaerobic sludge blanket reactor: Impacts of effluent recirculation on reactor performance. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2020; 274:111157. [PMID: 32805474 DOI: 10.1016/j.jenvman.2020.111157] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Revised: 07/03/2020] [Accepted: 07/29/2020] [Indexed: 06/11/2023]
Abstract
Thermophilic anaerobic digestion is a promising process for high-solid blackwater (BW) treatment due to improved hydrolysis rates, high methanogenesis efficiency, and pathogen removal, when compared with mesophilic treatment. In the present work, the effects of effluent recirculation (i.e., mixing) on thermophilic blackwater treatment were studied. A laboratory-scale thermophilic upflow anaerobic sludge blanket reactor was operated with and without effluent recirculation. The methanogenesis efficiency of the BW treatment increased from 45.0 ± 2.9% when effluent recirculation was applied to 56.7 ± 5.5% without effluent recirculation. Without effluent recirculation, the COD accumulation in the bioreactor was reduced from 17.2 to 3.8% and the effluent volatile fatty acids (VFA) concentration was reduced from 0.64 ± 0.18 to 0.15 ± 0.10 g/L. Further, both acetoclastic and hydrogenotrophic methanogenic activity increased from 101.3 ± 10.8 and 93.9 ± 6.1 to 120.4 ± 9.4 and 118.2 ± 13.2 mg CH4-COD/(gVSS⋅d), respectively, after effluent recirculation was discontinued. The predominant methanogens changed from Methanothermobacter (67%) with effluent recirculation to Methanosarcina (62%) without effluent recirculation. As compared to the effluent recirculation conditions, the enhanced biomethane recovery and treatment performance without effluent recirculation can be attributed to the close proximity of bacteria and archaea groups and the reduced VFA accumulation. Predicted functional gene comparison showed higher prevalence of function for intermediate metabolite transportation (transporters, ATP-binding cassette (ABC) transporters, and two-component system) after discontinuing effluent circulation, which contributed to improved syntrophic propionate oxidation and syntrophic acetate oxidization and enhanced hydrogenotrophic methanogenesis.
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Affiliation(s)
- Lei Zhang
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Canada
| | - Bing Guo
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Canada
| | - Anqi Mou
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Canada
| | - Ran Li
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Canada; College of Petroleum Engineering, Xi'an Shiyou University, Xi'an, 710065, Shaanxi Province, China
| | - Yang Liu
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Canada.
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18
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Matsakas L, Sarkar O, Jansson S, Rova U, Christakopoulos P. A novel hybrid organosolv-steam explosion pretreatment and fractionation method delivers solids with superior thermophilic digestibility to methane. BIORESOURCE TECHNOLOGY 2020; 316:123973. [PMID: 32799045 DOI: 10.1016/j.biortech.2020.123973] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Revised: 08/03/2020] [Accepted: 08/04/2020] [Indexed: 06/11/2023]
Abstract
Rising environmental concerns and the imminent depletion of fossil resources have sparked a strong interest towards the production of renewable energy such as biomethane. Inclusion of alternative feedstock's such as lignocellulosic biomass could further expand the production of biomethane. The present study evaluated the potential of a novel hybrid organosolv-steam explosion fractionation for delivering highly digestible pretreated solids from birch and spruce woodchips. The highest methane production yield was 176.5 mLCH4 gVS-1 for spruce and 327.2 mL CH4 gVS-1 for birch. High methane production rates of 1.0-6.3 mL min-1 (spruce) and 6.0-35.5 mL min-1 (birch) were obtained, leading to a rapid digestion, with 92% of total methane from spruce being generated in 80 h and 95% of that from birch in 120 h. These results demonstrate the elevated potential of the novel method to fractionate spruce and birch biomass and deliver cellulose-rich pretreated solids with superior digestibility.
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Affiliation(s)
- Leonidas Matsakas
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental, and Natural Resources Engineering, Luleå University of Technology, 971‑87 Luleå, Sweden.
| | - Omprakash Sarkar
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental, and Natural Resources Engineering, Luleå University of Technology, 971‑87 Luleå, Sweden
| | - Stina Jansson
- Department of Chemistry, Umeå University, 901 87 Umeå, Sweden
| | - Ulrika Rova
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental, and Natural Resources Engineering, Luleå University of Technology, 971‑87 Luleå, Sweden
| | - Paul Christakopoulos
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental, and Natural Resources Engineering, Luleå University of Technology, 971‑87 Luleå, Sweden
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19
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Shen N, Liang Z, Chen Y, Song H, Wan J. Enhancement of syntrophic acetate oxidation pathway via single walled carbon nanotubes addition under high acetate concentration and thermophilic condition. BIORESOURCE TECHNOLOGY 2020; 306:123182. [PMID: 32199400 DOI: 10.1016/j.biortech.2020.123182] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 03/07/2020] [Accepted: 03/12/2020] [Indexed: 06/10/2023]
Abstract
The effect of single walled carbon nanotubes (SWCNT) on methane production under high acetate concentration and thermophilic condition was evaluated. An isotope labeling experiment verified that >85% of methane was generated from syntrophic acetate oxidation (SAO) at 50, 100 and 150 mM acetate and almost 100% at 200 mM. SWCNT addition had little effect on the methanogenesis pathway, whereas it accelerated methane production via decreasing lag phase times and increasing maximum methane production rates. Electrochemical impedance spectroscopy (EIS) results revealed the electrical resistivity of sludge in groups of SWCNT was distinctly smaller than CK groups, indicating higher sludge conductivity was achieved. Further, the results of communities described that Coprothermobacter and Thermacetogenium played the most important role in SAO under all conditions. Meanwhile, the enriched Thermacetogenium and direct interspecies electron transfer (DIET) pathway in SAO consortia contributed to the acceleration of methane production via SWCNT addition.
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Affiliation(s)
- Nan Shen
- School of Environment, Nanjing Normal University, Nanjing, Jiangsu 210023, People's Republic of China
| | - Zhu Liang
- School of Environment, Nanjing Normal University, Nanjing, Jiangsu 210023, People's Republic of China
| | - Yun Chen
- School of Environment, Nanjing Normal University, Nanjing, Jiangsu 210023, People's Republic of China.
| | - Hailiang Song
- School of Environment, Nanjing Normal University, Nanjing, Jiangsu 210023, People's Republic of China
| | - Junfeng Wan
- School of Ecology and Environment, Zhengzhou University, Zhengzhou, Henan 450001, People's Republic of China
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20
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Chen H, Chang S. Dissecting methanogenesis for temperature-phased anaerobic digestion: Impact of temperature on community structure, correlation, and fate of methanogens. BIORESOURCE TECHNOLOGY 2020; 306:123104. [PMID: 32172088 DOI: 10.1016/j.biortech.2020.123104] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 02/23/2020] [Accepted: 02/27/2020] [Indexed: 06/10/2023]
Abstract
This study investigated the relationship between the temperature (35, 42, and 55 °C) used in temperature-phased anaerobic digestion (TPAD) and fate of methanogens between the two anaerobic digestion (AD) phases. Methanogens were profiled by using next generation sequencing (NGS) and droplet digital PCR approaches. The results showed that optimal combined temperatures for methane production were 55 °C during biological hydrolysis (BH) and 35 or 42 °C during AD. BH exhibited much lower archaeal population and was more susceptible to changes in temperature, compared to the AD phase. Additionally, we demonstrated, for the first time, that the BH step could affect the subsequent AD phase by altering AD methanogen composition and improve the stability of the process by enriching the rapidly growing Methanosarcina in the BH-AD process. These results are significant for understanding the mechanisms and stability of methane production in TPAD systems.
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Affiliation(s)
- Huibin Chen
- School of Engineering, University of Guelph, Ontario N1G 2W1, Canada; College of Life Sciences, Fujian Normal University, Fuzhou 350117, China
| | - Sheng Chang
- School of Engineering, University of Guelph, Ontario N1G 2W1, Canada.
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21
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Nozhevnikova AN, Russkova YI, Litti YV, Parshina SN, Zhuravleva EA, Nikitina AA. Syntrophy and Interspecies Electron Transfer in Methanogenic Microbial Communities. Microbiology (Reading) 2020. [DOI: 10.1134/s0026261720020101] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
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22
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Hupfauf S, Winkler A, Wagner AO, Podmirseg SM, Insam H. Biomethanation at 45 °C offers high process efficiency and supports hygienisation. BIORESOURCE TECHNOLOGY 2020; 300:122671. [PMID: 31901776 DOI: 10.1016/j.biortech.2019.122671] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 12/19/2019] [Accepted: 12/21/2019] [Indexed: 06/10/2023]
Abstract
The aim of this work was to prove a process temperature of 45 °C as a practical alternative to commonly applied mesophilic (37 °C) and thermophilic (55 °C) anaerobic digestion (AD). Regarding methane production, no differences were found between the three temperature regimes. However, the maximum possible loading rate at 45 °C exceeded that at 37 °C and 55 °C. Pathogen inactivation at 45 °C was higher than at 37 °C and similarly efficient as at 55 °C. At each process temperature, a unique microbial community established. In addition, the archaeome at 55 °C was dominated by hydrogenotrophs, while at 37 °C and 45 °C it was dominated by acetotrophs. For the investigated substrate mixture, liquid cattle manure with wheat straw as co-substrate, 45 °C turned out to be preferable for AD. For other substrates, these findings still need to be confirmed.
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Affiliation(s)
- Sebastian Hupfauf
- Department of Microbiology, University of Innsbruck, Technikerstraße 25d, 6020 Innsbruck, Austria.
| | - Anna Winkler
- Department of Microbiology, University of Innsbruck, Technikerstraße 25d, 6020 Innsbruck, Austria
| | - Andreas Otto Wagner
- Department of Microbiology, University of Innsbruck, Technikerstraße 25d, 6020 Innsbruck, Austria
| | - Sabine Marie Podmirseg
- Department of Microbiology, University of Innsbruck, Technikerstraße 25d, 6020 Innsbruck, Austria
| | - Heribert Insam
- Department of Microbiology, University of Innsbruck, Technikerstraße 25d, 6020 Innsbruck, Austria
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23
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Fernandez‐Gonzalez N, Pedizzi C, Lema JM, Carballa M. Air-side ammonia stripping coupled to anaerobic digestion indirectly impacts anaerobic microbiome. Microb Biotechnol 2019; 12:1403-1416. [PMID: 31532080 PMCID: PMC6801131 DOI: 10.1111/1751-7915.13482] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 06/26/2019] [Accepted: 08/13/2019] [Indexed: 11/29/2022] Open
Abstract
Air-side stripping without a prior solid-liquid phase separation step is a feasible and promising process to control ammonia concentration in thermophilic digesters. During the process, part of the anaerobic biomass is exposed to high temperature, high pH and aerobic conditions. However, there are no studies assessing the effects of those harsh conditions on the microbial communities of thermophilic digesters. To fill this knowledge gap, the microbiomes of two thermophilic digesters (55°C), fed with a mixture of pig manure and nitrogen-rich co-substrates, were investigated under different organic loading rates (OLR: 1.1-5.2 g COD l-1 day-1 ), ammonia concentrations (0.2-1.5 g free ammonia nitrogen l-1 ) and stripping frequencies (3-5 times per week). The bacterial communities were dominated by Firmicutes and Bacteroidetes phyla, while the predominant methanogens were Methanosarcina sp archaea. Increasing co-substrate fraction, OLR and free ammonia nitrogen (FAN) favoured the presence of genera Ruminiclostridium, Clostridium and Tepidimicrobium and of hydrogenotrophic methanogens, mainly Methanoculleus archaea. The data indicated that the use of air-side stripping did not adversely affect thermophilic microbial communities, but indirectly modulated them by controlling FAN concentrations in the digester. These results demonstrate the viability at microbial community level of air side-stream stripping process as an adequate technology for the ammonia control during anaerobic co-digestion of nitrogen-rich substrates.
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Affiliation(s)
- Nuria Fernandez‐Gonzalez
- Department of Chemical EngineeringUniversidade de Santiago de CompostelaRúa Lope Gómez de Marzoa, s/n.15782Santiago de CompostelaSpain
- Present address:
Present address:Department of Chemical Engineering and Environmental TechnologyValladolid UniversityDr. Mergelina, s/n47011ValladolidSpain
| | - Chiara Pedizzi
- Department of Chemical EngineeringUniversidade de Santiago de CompostelaRúa Lope Gómez de Marzoa, s/n.15782Santiago de CompostelaSpain
| | - Juan M. Lema
- Department of Chemical EngineeringUniversidade de Santiago de CompostelaRúa Lope Gómez de Marzoa, s/n.15782Santiago de CompostelaSpain
| | - Marta Carballa
- Department of Chemical EngineeringUniversidade de Santiago de CompostelaRúa Lope Gómez de Marzoa, s/n.15782Santiago de CompostelaSpain
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24
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Lv Z, Wu X, Zhou B, Wang Y, Sun Y, Wang Y, Chen Z, Zhang J. Effect of one step temperature increment from mesophilic to thermophilic anaerobic digestion on the linked pattern between bacterial and methanogenic communities. BIORESOURCE TECHNOLOGY 2019; 292:121968. [PMID: 31430671 DOI: 10.1016/j.biortech.2019.121968] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2019] [Revised: 08/05/2019] [Accepted: 08/06/2019] [Indexed: 05/28/2023]
Abstract
Process fluctuation caused by temperature modification of anaerobic digestion is routinely monitored via operational parameters, such as pH and gas production, but these parameters are lagging on microbial community performance. In this study, 13C isotope fractionation in CH4 and CO2 of biogas together with microbial community dynamics were applied to evaluate process stability in response to temperature increment. Results showed that the weakening correlated links between Firmicutes affiliated families and Methanomicrobiaceae were found regarding temperature increase. In contrast, Methanosarcinaceae and Methanobacteriaceae strengthened their links with multiple bacterial groups. This suggests that the 13C isotope fractionation in CH4 can predict the collapse of certain microbial interconnections and process instability, the new reinforced microbial links directly reflect the microbial community redundancy for maintaining function of syntrophic populations.
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Affiliation(s)
- Zuopeng Lv
- The Key Laboratory of Biotechnology for Medicinal Plants of Jiangsu Province, School of Life, Jiangsu Normal University, Shanghai Road 101, 221116 Xuzhou, China.
| | - Xiayuan Wu
- Bioenergy Research Institute, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Bingqian Zhou
- The Key Laboratory of Biotechnology for Medicinal Plants of Jiangsu Province, School of Life, Jiangsu Normal University, Shanghai Road 101, 221116 Xuzhou, China
| | - Yan Wang
- The Key Laboratory of Biotechnology for Medicinal Plants of Jiangsu Province, School of Life, Jiangsu Normal University, Shanghai Road 101, 221116 Xuzhou, China
| | - Ying Sun
- The Key Laboratory of Biotechnology for Medicinal Plants of Jiangsu Province, School of Life, Jiangsu Normal University, Shanghai Road 101, 221116 Xuzhou, China
| | - Yanfang Wang
- The Key Laboratory of Biotechnology for Medicinal Plants of Jiangsu Province, School of Life, Jiangsu Normal University, Shanghai Road 101, 221116 Xuzhou, China
| | - Zhongbing Chen
- Department of Applied Ecology, Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Kamýcká 129, 16500 Prague, Czech Republic
| | - Jianfeng Zhang
- Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
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25
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Fu B, Jin X, Conrad R, Liu H, Liu H. Competition Between Chemolithotrophic Acetogenesis and Hydrogenotrophic Methanogenesis for Exogenous H 2/CO 2 in Anaerobically Digested Sludge: Impact of Temperature. Front Microbiol 2019; 10:2418. [PMID: 31749772 PMCID: PMC6842956 DOI: 10.3389/fmicb.2019.02418] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 10/07/2019] [Indexed: 11/13/2022] Open
Abstract
Anaerobic digestion is a widely applied technology for sewage sludge treatment. Hydrogen and CO2 are important degradation products, which serve as substrates for both hydrogenotrophic methanogenesis and chemolithotrophic acetogenesis. In order to understand the competition between these processes for H2/CO2, sludge samples were incubated under H2/CO2 headspace at different temperatures, and analyzed with respect to turnover of H2, CO2, CH4 and acetate including their δ13C values. At 15°C, 13C-depleted acetate (δ13C of -41 to -43‰) and transient acetate accumulation were observed under H2/CO2, and CH4 accumulated with δ13C values increasing from -53 to -33‰. The copy numbers of the fhs gene, which is characteristic for acetogenic bacteria, were at 15°C one order of magnitude higher in the H2/CO2 incubations than the N2 control. At 30°C, however, acetate did not accumulate in the H2/CO2 incubation and the δ13C of CH4 was very low (-100 to -77‰). At 50°C, isotopically enriched acetate was transiently formed and subsequently consumed followed by the production of 13C-depleted CH4. Collectively, the results indicate a high contribution of chemolithotrophic acetogenesis to H2/CO2 utilization at 15°C and 50°C, while H2/CO2 was mainly consumed by hydrogenotrophic methanogenesis at 30°C. Fermentative production and methanogenic consumption of acetate were active at 50°C.
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Affiliation(s)
- Bo Fu
- Jiangsu Key Laboratory of Anaerobic Biotechnology, School of Environmental and Civil Engineering, Jiangnan University, Wuxi, China.,Department of Biogeochemistry, Max Planck Institute for Terrestrial Microbiology, Marburg, Germany.,Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, Suzhou, China
| | - Xin Jin
- Jiangsu Key Laboratory of Anaerobic Biotechnology, School of Environmental and Civil Engineering, Jiangnan University, Wuxi, China
| | - Ralf Conrad
- Department of Biogeochemistry, Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
| | - Hongbo Liu
- Jiangsu Key Laboratory of Anaerobic Biotechnology, School of Environmental and Civil Engineering, Jiangnan University, Wuxi, China.,Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, Suzhou, China
| | - He Liu
- Jiangsu Key Laboratory of Anaerobic Biotechnology, School of Environmental and Civil Engineering, Jiangnan University, Wuxi, China.,Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, Suzhou, China
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26
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Mahdy A, Wandera SM, Bi S, Song Y, Qiao W, Dong R. Response of the microbial community to the methanogenic performance of biologically hydrolyzed sewage sludge with variable hydraulic retention times. BIORESOURCE TECHNOLOGY 2019; 288:121581. [PMID: 31158775 DOI: 10.1016/j.biortech.2019.121581] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2019] [Revised: 05/26/2019] [Accepted: 05/27/2019] [Indexed: 06/09/2023]
Abstract
Hyperthermophilic biological hydrolysis of sewage sludge was applied before long-term anaerobic digestion to investigate how shortening hydraulic retention times (HRT, 20-5d) affected methanogenic performances and microbial dynamics. Results indicated that although the three different HRTs provided a stable process with a steady-state of methane production, both methane yield (161 L kg-VSin-1, 25% higher) and volatile solids removal (VS, 50%, 2-fold higher) increased during longer HRTs. Redundancy analysis results indicated that Sporosarcina and Methnosarcina positively correlated to VS removal and methane yield, and negatively correlated to volatile fatty acids (VFAs) accumulation. The relative abundance of Coprothermobacter (>60%), syntrophic acetate oxidation bacteria (SAOB), and Methanospirillum (8-15%), increased during shorter HRTs. A slight shift to two-stage acetate conversion was observed during shorter HRTs. The results demonstrated that HRTs played a key role in shaping microbial structure, leading to a new steady-state of microbial community profiles and process performances at variable HRTs.
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Affiliation(s)
- Ahmed Mahdy
- College of Engineering, China Agricultural University, Beijing 100083, China; Department of Agricultural Microbiology, Faculty of Agriculture, Zagazig University, 44511 Zagazig, Egypt
| | - Simon M Wandera
- College of Engineering, China Agricultural University, Beijing 100083, China
| | - Shaojie Bi
- College of Engineering, China Agricultural University, Beijing 100083, China; State R&D Center for Efficient Production and Comprehensive Utilization of Biobased Gaseous Fuels, Energy Authority, National Development, and Reform Committee, Beijing 100083, China
| | - Yunlong Song
- College of Engineering, China Agricultural University, Beijing 100083, China; State R&D Center for Efficient Production and Comprehensive Utilization of Biobased Gaseous Fuels, Energy Authority, National Development, and Reform Committee, Beijing 100083, China
| | - Wei Qiao
- College of Engineering, China Agricultural University, Beijing 100083, China; State R&D Center for Efficient Production and Comprehensive Utilization of Biobased Gaseous Fuels, Energy Authority, National Development, and Reform Committee, Beijing 100083, China
| | - Renjie Dong
- College of Engineering, China Agricultural University, Beijing 100083, China; State R&D Center for Efficient Production and Comprehensive Utilization of Biobased Gaseous Fuels, Energy Authority, National Development, and Reform Committee, Beijing 100083, China
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27
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Westerholm M, Dolfing J, Schnürer A. Growth Characteristics and Thermodynamics of Syntrophic Acetate Oxidizers. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:5512-5520. [PMID: 30990997 DOI: 10.1021/acs.est.9b00288] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Syntrophic acetate oxidation (SAO) plays a pivotal role in biogas production processes when aceticlastic methanogens are inhibited. Despite the importance of SAO, the metabolic interactions and syntrophic growth of the organisms involved are still poorly understood. Therefore, we studied growth parameters and interactions within constructed defined cocultures comprising the methanogen Methanoculleus bourgensis and one, or several, of the syntrophic acetate oxidizers Syntrophaceticus schinkii, [ Clostridium] ultunense, and Tepidanaerobacter acetatoxydans and a novel, uncharacterized bacterium. Cultivation experiments in a design-of-experiment approach revealed positive effects on methane production rate of increased ammonium levels (up to 0.2 M), temperature (up to 45 °C), and acetate concentrations (0.15-0.30 M). Molecular analyses and thermodynamic calculations demonstrated close interlinkages between the microorganisms, with available energies of -10 kJ/mol for acetate oxidation and -20 kJ/mol for hydrogenotrophic methanogenesis. The estimated generation time varied between 3 and 20 days for all syntrophic microorganisms involved, and the acetate minimum threshold level was 0.40-0.45 mM. The rate of methanogenesis depended on the SAO bacteria present in the culture. These data are beneficial for interpretation of SAO prevalence and competiveness against aceticlastic methanogens in anaerobic environments.
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Affiliation(s)
- Maria Westerholm
- Department of Microbiology , Swedish University of Agricultural Sciences , Uppsala BioCenter, Box 7025, SE-750 07 Uppsala , Sweden
| | - Jan Dolfing
- School of Engineering , Newcastle University , Newcastle-upon-Tyne NE1 7RU United Kingdom
| | - Anna Schnürer
- Department of Microbiology , Swedish University of Agricultural Sciences , Uppsala BioCenter, Box 7025, SE-750 07 Uppsala , Sweden
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28
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Fischer MA, Güllert S, Refai S, Künzel S, Deppenmeier U, Streit WR, Schmitz RA. Long-term investigation of microbial community composition and transcription patterns in a biogas plant undergoing ammonia crisis. Microb Biotechnol 2019; 12:305-323. [PMID: 30381904 PMCID: PMC6390037 DOI: 10.1111/1751-7915.13313] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 08/22/2018] [Accepted: 08/24/2018] [Indexed: 02/01/2023] Open
Abstract
Ammonia caused disturbance of biogas production is one of the most frequent incidents in regular operation of biogas reactors. This study provides a detailed insight into the microbial community of a mesophilic, full-scale biogas reactor (477 kWh h-1 ) fed with maize silage, dried poultry manure and cow manure undergoing initial process disturbance by increased ammonia concentration. Over a time period of 587 days, the microbial community of the reactor was regularly monitored on a monthly basis by high-throughput amplicon sequencing of the archaeal and bacterial 16S rRNA genes. During this sampling period, the total ammonia concentrations varied between 2.7 and 5.8 g l-1 [NH4 + -N]. To gain further inside into the active metabolic pathways, for selected time points metatranscriptomic shotgun analysis was performed allowing the quantification of marker genes for methanogenesis, hydrolysis and syntrophic interactions. The results obtained demonstrated a microbial community typical for a mesophilic biogas plant. However in response to the observed changing process conditions (e.g. increasing NH4 + levels, changing feedstock composition), the microbial community reacted highly flexible by changing and adapting the community composition. The Methanosarcina-dominated archaeal community was shifted to a Methanomicrobiales-dominated archaeal community in the presence of increased ammonia conditions. A similar trend as in the phylogenetic composition was observed in the transcription activity of genes coding for enzymes involved in acetoclastic methanogenesis and syntrophic acetate oxidations (Codh/Acs and Fthfs). In accordance, Clostridia simultaneously increased under elevated ammonia concentrations in abundance and were identified as the primary syntrophic interaction partner with the now Methanomicrobiales-dominated archaeal community. In conclusion, overall stable process performance was maintained during increased ammonia concentration in the studied reactor based on the microbial communities' ability to flexibly respond by reorganizing the community composition while remaining functionally stable.
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MESH Headings
- Ammonia/metabolism
- Archaea/classification
- Archaea/genetics
- Bacteria/classification
- Bacteria/genetics
- Biofuels/microbiology
- Bioreactors/microbiology
- Cluster Analysis
- Culture Media/chemistry
- DNA, Archaeal/chemistry
- DNA, Archaeal/genetics
- DNA, Bacterial/chemistry
- DNA, Bacterial/genetics
- DNA, Ribosomal/chemistry
- DNA, Ribosomal/genetics
- Longitudinal Studies
- Microbiota
- Phylogeny
- RNA, Ribosomal, 16S/genetics
- Sequence Analysis, DNA
- Transcription, Genetic
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Affiliation(s)
- Martin Alexander Fischer
- Institute of General MicrobiologyChristian‐Albrechts‐University KielAm Botanischen Garten 1‐924118KielGermany
| | - Simon Güllert
- Institute of General MicrobiologyChristian‐Albrechts‐University KielAm Botanischen Garten 1‐924118KielGermany
- Institute of Microbiology & BiotechnologyUniversity HamburgBiozentrum Klein FlottbekHamburgGermany
| | - Sarah Refai
- Institute of Microbiology & BiotechnologyUniversity BonnMeckenheimer Allee 16853115BonnGermany
| | - Sven Künzel
- Max‐Planck‐Institute of Evolutionary BiologyAugust‐Thienemann‐Str. 224306PlönGermany
| | - Uwe Deppenmeier
- Institute of Microbiology & BiotechnologyUniversity BonnMeckenheimer Allee 16853115BonnGermany
| | - Wolfgang R. Streit
- Institute of Microbiology & BiotechnologyUniversity HamburgBiozentrum Klein FlottbekHamburgGermany
| | - Ruth Anne Schmitz
- Institute of General MicrobiologyChristian‐Albrechts‐University KielAm Botanischen Garten 1‐924118KielGermany
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29
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Fu B, Jin X, Conrad R, Liu H, Liu H. Competition Between Chemolithotrophic Acetogenesis and Hydrogenotrophic Methanogenesis for Exogenous H 2/CO 2 in Anaerobically Digested Sludge: Impact of Temperature. Front Microbiol 2019; 10:2418. [PMID: 31749772 DOI: 10.3389/fmicb.2019.02418/full] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 10/07/2019] [Indexed: 05/21/2023] Open
Abstract
Anaerobic digestion is a widely applied technology for sewage sludge treatment. Hydrogen and CO2 are important degradation products, which serve as substrates for both hydrogenotrophic methanogenesis and chemolithotrophic acetogenesis. In order to understand the competition between these processes for H2/CO2, sludge samples were incubated under H2/CO2 headspace at different temperatures, and analyzed with respect to turnover of H2, CO2, CH4 and acetate including their δ13C values. At 15°C, 13C-depleted acetate (δ13C of -41 to -43‰) and transient acetate accumulation were observed under H2/CO2, and CH4 accumulated with δ13C values increasing from -53 to -33‰. The copy numbers of the fhs gene, which is characteristic for acetogenic bacteria, were at 15°C one order of magnitude higher in the H2/CO2 incubations than the N2 control. At 30°C, however, acetate did not accumulate in the H2/CO2 incubation and the δ13C of CH4 was very low (-100 to -77‰). At 50°C, isotopically enriched acetate was transiently formed and subsequently consumed followed by the production of 13C-depleted CH4. Collectively, the results indicate a high contribution of chemolithotrophic acetogenesis to H2/CO2 utilization at 15°C and 50°C, while H2/CO2 was mainly consumed by hydrogenotrophic methanogenesis at 30°C. Fermentative production and methanogenic consumption of acetate were active at 50°C.
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Affiliation(s)
- Bo Fu
- Jiangsu Key Laboratory of Anaerobic Biotechnology, School of Environmental and Civil Engineering, Jiangnan University, Wuxi, China
- Department of Biogeochemistry, Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
- Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, Suzhou, China
| | - Xin Jin
- Jiangsu Key Laboratory of Anaerobic Biotechnology, School of Environmental and Civil Engineering, Jiangnan University, Wuxi, China
| | - Ralf Conrad
- Department of Biogeochemistry, Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
| | - Hongbo Liu
- Jiangsu Key Laboratory of Anaerobic Biotechnology, School of Environmental and Civil Engineering, Jiangnan University, Wuxi, China
- Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, Suzhou, China
| | - He Liu
- Jiangsu Key Laboratory of Anaerobic Biotechnology, School of Environmental and Civil Engineering, Jiangnan University, Wuxi, China
- Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, Suzhou, China
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30
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Zhang S, Chang J, Liu W, Pan Y, Cui K, Chen X, Liang P, Zhang X, Wu Q, Qiu Y, Huang X. A novel bioaugmentation strategy to accelerate methanogenesis via adding Geobacter sulfurreducens PCA in anaerobic digestion system. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 642:322-326. [PMID: 29906723 DOI: 10.1016/j.scitotenv.2018.06.043] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 06/04/2018] [Accepted: 06/04/2018] [Indexed: 06/08/2023]
Abstract
Based on the new syntrophic methanogenesis route via direct interspecies electron transfer (DIET), a novel bioaugmentation method by adding exoelectrogenic Geobacter species to accelerate methanogenesis was developed in this study. Geobacter sulfurreducens PCA, type exoelectrogenic strain of Geobacter species was chosen for the research. To clarify the effect of G. sulfurreducens on methanogenesis, batch tests of CH4 production were carried out. Acetate, the most typical precursor of methanogenesis was chosen as the substrate of batch tests. Amendment of G. sulfurreducens accelerated CH4 production remarkably. The lag phase of CH4 production was shortened, and the maximum CH4 production rate was increased by 78%. Fluorescence in situ hybridization showed that G. sulfurreducens closely gathered with methanogens. For the archaeal communities, the high-throughput sequencing results demonstrated that Methanosaetaceae and Methanobacteriaceae were potential bioaugmented methanogens. We speculated that the accelerated methanogenesis by adding G. sulfurreducens may result from the syntrophic association between G. sulfurreducens and methanogens affiliated with Methanosaetaceae and Methanobacteriaceae. This research provides a new route to enhance methanogenesis through the utilization of G. sulfurreducens. Through this study, the role of Geobacter in the anaerobic engineering and carbon cycling of nature should be paid more attention.
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Affiliation(s)
- Shuo Zhang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Jiali Chang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Wei Liu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Yiran Pan
- School of Resources & Environmental Engineering, Hefei University of Technology, Anhui Province 230009, China
| | - Kangping Cui
- School of Resources & Environmental Engineering, Hefei University of Technology, Anhui Province 230009, China
| | - Xi Chen
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Peng Liang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Xiaoyuan Zhang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Qing Wu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Yong Qiu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Xia Huang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
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31
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Šafarič L, Shakeri Yekta S, Liu T, Svensson BH, Schnürer A, Bastviken D, Björn A. Dynamics of a Perturbed Microbial Community during Thermophilic Anaerobic Digestion of Chemically Defined Soluble Organic Compounds. Microorganisms 2018; 6:microorganisms6040105. [PMID: 30314333 PMCID: PMC6313639 DOI: 10.3390/microorganisms6040105] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 10/06/2018] [Accepted: 10/10/2018] [Indexed: 11/22/2022] Open
Abstract
Knowledge of microbial community dynamics in relation to process perturbations is fundamental to understand and deal with the instability of anaerobic digestion (AD) processes. This study aims to investigate the microbial community structure and function of a thermophilic AD process, fed with a chemically defined substrate, and its association with process performance stability. Next generation amplicon sequencing of 16S ribosomal RNA (rRNA) genes revealed that variations in relative abundances of the predominant bacterial species, Defluviitoga tunisiensis and Anaerobaculum hydrogeniformans, were not linked to the process performance stability, while dynamics of bacterial genera of low abundance, Coprothermobacter and Defluviitoga (other than D. tunisiensis), were associated with microbial community function and process stability. A decrease in the diversity of the archaeal community was observed in conjunction with process recovery and stable performance, implying that the high abundance of specific archaeal group(s) contributed to the stable AD. Dominance of hydrogenotrophic Methanoculleus particularly corresponded to an enhanced microbial acetate and propionate turnover capacity, whereas the prevalence of hydrogenotrophic Methanothermobacter and acetoclastic Methanosaeta was associated with instable AD. Acetate oxidation via syntrophic interactions between Coprothermobacter and Methanoculleus was potentially the main methane-formation pathway during the stable process. We observed that supplementation of Se and W to the medium improved the propionate turnover by the thermophilic consortium. The outcomes of our study provided insights into the community dynamics and trace element requirements in relation to the process performance stability of thermophilic AD.
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Affiliation(s)
- Luka Šafarič
- Department of Thematic Studies-Environmental Change, Linköping University, 581 83 Linköping, Sweden.
- Biogas Research Center, Linköping University, 581 83 Linköping, Sweden.
| | - Sepehr Shakeri Yekta
- Department of Thematic Studies-Environmental Change, Linköping University, 581 83 Linköping, Sweden.
- Biogas Research Center, Linköping University, 581 83 Linköping, Sweden.
| | - Tong Liu
- Department of Molecular Science, Swedish University of Agricultural Science, Uppsala BioCenter, 75007 Uppsala, Sweden.
| | - Bo H Svensson
- Department of Thematic Studies-Environmental Change, Linköping University, 581 83 Linköping, Sweden.
- Biogas Research Center, Linköping University, 581 83 Linköping, Sweden.
| | - Anna Schnürer
- Department of Thematic Studies-Environmental Change, Linköping University, 581 83 Linköping, Sweden.
- Biogas Research Center, Linköping University, 581 83 Linköping, Sweden.
- Department of Molecular Science, Swedish University of Agricultural Science, Uppsala BioCenter, 75007 Uppsala, Sweden.
| | - David Bastviken
- Department of Thematic Studies-Environmental Change, Linköping University, 581 83 Linköping, Sweden.
| | - Annika Björn
- Department of Thematic Studies-Environmental Change, Linköping University, 581 83 Linköping, Sweden.
- Biogas Research Center, Linköping University, 581 83 Linköping, Sweden.
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32
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Liang X, Whitham JM, Holwerda EK, Shao X, Tian L, Wu YW, Lombard V, Henrissat B, Klingeman DM, Yang ZK, Podar M, Richard TL, Elkins JG, Brown SD, Lynd LR. Development and characterization of stable anaerobic thermophilic methanogenic microbiomes fermenting switchgrass at decreasing residence times. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:243. [PMID: 30202438 PMCID: PMC6126044 DOI: 10.1186/s13068-018-1238-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Accepted: 08/27/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND Anaerobic fermentation of lignocellulose occurs in both natural and managed environments, and is an essential part of the carbon cycle as well as a promising route to sustainable production of fuels and chemicals. Lignocellulose solubilization by mixed microbiomes is important in these contexts. RESULTS Here, we report the development of stable switchgrass-fermenting enrichment cultures maintained at various residence times and moderately high (55 °C) temperatures. Anaerobic microbiomes derived from a digester inoculum were incubated at 55 °C and fed semi-continuously with medium containing 30 g/L mid-season harvested switchgrass to achieve residence times (RT) of 20, 10, 5, and 3.3 days. Stable, time-invariant cellulolytic methanogenic cultures with minimal accumulation of organic acids were achieved for all RTs. Fractional carbohydrate solubilization was 0.711, 0.654, 0.581 and 0.538 at RT = 20, 10, 5 and 3.3 days, respectively, and glucan solubilization was proportional to xylan solubilization at all RTs. The rate of solubilization was described well by the equation r = k(C - C0fr), where C represents the concentration of unutilized carbohydrate, C0 is the concentration of carbohydrate (cellulose and hemicellulose) entering the bioreactor and fr is the extrapolated fraction of entering carbohydrate that is recalcitrant at infinite residence time. The 3.3 day RT is among the shortest RT reported for stable thermophilic, methanogenic digestion of a lignocellulosic feedstock. 16S rDNA phylotyping and metagenomic analyses were conducted to characterize the effect of RT on community dynamics and to infer functional roles in the switchgrass to biogas conversion to the various microbial taxa. Firmicutes were the dominant phylum, increasing in relative abundance from 54 to 96% as RT decreased. A Clostridium clariflavum strain with genetic markers for xylose metabolism was the most abundant lignocellulose-solubilizing bacterium. A Thermotogae (Defluviitoga tunisiensis) was the most abundant bacterium in switchgrass digesters at RT = 20 days but decreased in abundance at lower RTs as did multiple Chloroflexi. Synergistetes and Euryarchaeota were present at roughly constant levels over the range of RTs examined. CONCLUSIONS A system was developed in which stable methanogenic steady-states were readily obtained with a particulate biomass feedstock, mid-season switchgrass, at laboratory (1 L) scale. Characterization of the extent and rate of carbohydrate solubilization in combination with 16S rDNA and metagenomic sequencing provides a multi-dimensional view of performance, species composition, glycoside hydrolases, and metabolic function with varying residence time. These results provide a point of reference and guidance for future studies and organism development efforts involving defined cultures.
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Affiliation(s)
- Xiaoyu Liang
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755 USA
- BioEnergy Sciences Center, Oak Ridge, TN 37830 USA
| | - Jason M. Whitham
- BioEnergy Sciences Center, Oak Ridge, TN 37830 USA
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830 USA
| | - Evert K. Holwerda
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755 USA
- BioEnergy Sciences Center, Oak Ridge, TN 37830 USA
| | - Xiongjun Shao
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755 USA
- BioEnergy Sciences Center, Oak Ridge, TN 37830 USA
| | - Liang Tian
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755 USA
- BioEnergy Sciences Center, Oak Ridge, TN 37830 USA
| | - Yu-Wei Wu
- Graduate Institute of Biomedical Informatics, College of Medical Science and Technology, Taipei Medical University, Taipei, 106 Taiwan
| | - Vincent Lombard
- CNRS, UMR 7257, Aix-Marseille University, 13288 Marseille, France
- INRA, USC 1408 AFMB, 13288 Marseille, France
| | - Bernard Henrissat
- CNRS, UMR 7257, Aix-Marseille University, 13288 Marseille, France
- INRA, USC 1408 AFMB, 13288 Marseille, France
- Department of Biological Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Dawn M. Klingeman
- BioEnergy Sciences Center, Oak Ridge, TN 37830 USA
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830 USA
| | - Zamin K. Yang
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830 USA
| | - Mircea Podar
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830 USA
| | - Tom L. Richard
- Department of Agricultural and Biological Engineering, The Pennsylvania State University, University Park, State College, PA 16802 USA
| | - James G. Elkins
- BioEnergy Sciences Center, Oak Ridge, TN 37830 USA
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830 USA
| | - Steven D. Brown
- BioEnergy Sciences Center, Oak Ridge, TN 37830 USA
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37830 USA
- Present Address: LanzaTech, Inc., Skokie, IL 60077 USA
| | - Lee R. Lynd
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755 USA
- BioEnergy Sciences Center, Oak Ridge, TN 37830 USA
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Yin DM, Westerholm M, Qiao W, Bi SJ, Wandera SM, Fan R, Jiang MM, Dong RJ. An explanation of the methanogenic pathway for methane production in anaerobic digestion of nitrogen-rich materials under mesophilic and thermophilic conditions. BIORESOURCE TECHNOLOGY 2018; 264:42-50. [PMID: 29783130 DOI: 10.1016/j.biortech.2018.05.062] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 05/15/2018] [Accepted: 05/17/2018] [Indexed: 06/08/2023]
Abstract
The impact of temperature on the anaerobic digestion of chicken manure was investigated by studying the process performance and pathway for continuously-fed digesters under mesophilic and thermophilic conditions. The mesophilic digester obtained a 15% higher methane yield compared with the thermophilic digester. Mesophilic and thermophilic digester had free ammonia of 31 and 145 mg/L, respectively. The stable carbon isotope analysis indicated that 41% and 50% of acetate was converted to methane through the syntrophic acetate oxidation and hydrogenotrophic methanogenesis (SAO-HM) pathway under mesophilic and thermophilic conditions, respectively. The genus Pseudomonas represented 10% and 16% under mesophilic and thermophilic conditions, respectively. A high abundance of the methanogens genus Methanoculleus (94% of total methanogens) in mesophilic and the genus Methanothermobacter (96%) in thermophilic digesters indicated they were the main hydrogenotrophic partners in SAO. The present study therefore illustrated that methanogenic pathway shifting, induced by free ammonia, closely correlated to the process performance.
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Affiliation(s)
- Dong-Min Yin
- College of Engineering, China Agricultural University, Beijing 100083, China; R&D Center for Efficient Production and Comprehensive Utilization of Biobased Gaseous Fuels, Energy Authority, National Development and Reform Committee (BGFeuls), Beijing 100083, China
| | - Maria Westerholm
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, Uppsala BioCenter, Box 7025, SE-750 07 Uppsala, Sweden
| | - Wei Qiao
- College of Engineering, China Agricultural University, Beijing 100083, China; R&D Center for Efficient Production and Comprehensive Utilization of Biobased Gaseous Fuels, Energy Authority, National Development and Reform Committee (BGFeuls), Beijing 100083, China.
| | - Shao-Jie Bi
- College of Engineering, China Agricultural University, Beijing 100083, China; R&D Center for Efficient Production and Comprehensive Utilization of Biobased Gaseous Fuels, Energy Authority, National Development and Reform Committee (BGFeuls), Beijing 100083, China
| | - Simon M Wandera
- College of Engineering, China Agricultural University, Beijing 100083, China; R&D Center for Efficient Production and Comprehensive Utilization of Biobased Gaseous Fuels, Energy Authority, National Development and Reform Committee (BGFeuls), Beijing 100083, China
| | - Run Fan
- College of Engineering, China Agricultural University, Beijing 100083, China; R&D Center for Efficient Production and Comprehensive Utilization of Biobased Gaseous Fuels, Energy Authority, National Development and Reform Committee (BGFeuls), Beijing 100083, China
| | - Meng-Meng Jiang
- College of Engineering, China Agricultural University, Beijing 100083, China; R&D Center for Efficient Production and Comprehensive Utilization of Biobased Gaseous Fuels, Energy Authority, National Development and Reform Committee (BGFeuls), Beijing 100083, China
| | - Ren-Jie Dong
- College of Engineering, China Agricultural University, Beijing 100083, China; R&D Center for Efficient Production and Comprehensive Utilization of Biobased Gaseous Fuels, Energy Authority, National Development and Reform Committee (BGFeuls), Beijing 100083, China
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Chen Y, Xiao K, Shen N, Zeng RJ, Zhou Y. Hydrogen production from a thermophilic alkaline waste activated sludge fermenter: Effects of solid retention time (SRT). CHEMOSPHERE 2018; 206:101-106. [PMID: 29734092 DOI: 10.1016/j.chemosphere.2018.04.170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 04/03/2018] [Accepted: 04/28/2018] [Indexed: 06/08/2023]
Abstract
This study aims to investigate the effects of solid retention times (SRTs) on hydrogen production via thermophilic alkaline fermentation of waste activated sludge. The reactor was subjected to a SRT from 10 to 6 days during approximately 82 days of operation. The results revealed that SRT had minor influence on hydrolysis and hydrolysis efficiency in different phases were from 48.11% to 50.55%. Nevertheless, the efficiency of acidogenesis process was highly related to SRT and longer SRT could enhance the acidogenesis. On the other hand, acidogenesis efficiency was also related to H2 partial pressure and high H2 partial pressure negatively affected the acidogenesis. Thus, the maximum acidification was achieved in phase 1 (21.29%) resulting in the maximum H2 yield in phase 1 (95.94 mL/g VSS; SRT = 10 days; H2 partial pressure = 0-18%). Phyla Actinobacteria and Proteobacteria, who are highly related to hydrolytic microbial population, were abundant in all phases that resulted in high hydrolysis extent. H2 production was attributed to the relative high abundance of Clostridia. Thus, this study suggested that longer SRT and lower H2 partial pressure was necessary to improve the H2 yield under alkaline pH condition.
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Affiliation(s)
- Yun Chen
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore 637141, Singapore; School of Environment, Nanjing Normal University, Nanjing, Jiangsu 210023, People's Republic of China; CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Keke Xiao
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore 637141, Singapore
| | - Nan Shen
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore 637141, Singapore; School of Environment, Nanjing Normal University, Nanjing, Jiangsu 210023, People's Republic of China
| | - Raymond J Zeng
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Yan Zhou
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore 637141, Singapore; School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore.
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Zhao J, Westerholm M, Qiao W, Yin D, Bi S, Jiang M, Dong R. Impact of temperature and substrate concentration on degradation rates of acetate, propionate and hydrogen and their links to microbial community structure. BIORESOURCE TECHNOLOGY 2018; 256:44-52. [PMID: 29428613 DOI: 10.1016/j.biortech.2018.01.150] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 01/29/2018] [Accepted: 01/31/2018] [Indexed: 05/25/2023]
Abstract
The present study investigates the conversion of acetate, propionate and hydrogen consumption linked to the microbial community structure and related to temperature and substrate concentration. Biogas reactors were continuously fed with coffee powder (20 g-COD/L) or acetate (20, 40, and 60 g-COD/L) and operated for 193 days at 37 °C or 55 °C conditions. Starting HRT was 23 days which was then reduced to 7 days. The kinetics of acetate and propionate degradation and hydrogen consumption rates were measured in batch assays. At HRT 7 days, the degradation rate of propionate was higher in thermophilic batches, while acetate degradation rate was higher at mesophilic conditions. The gaseous hydrogen consumption in acetate reactors increased proportionally with temperature and substrate concentration, while the dissolved hydrogen was not affected. The relative high abundance of hydrogentrophic methanogens indicated that the methanogenesis was directed towards the syntrophic acetate oxidation pathway at high acetate concentration and high temperature.
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Affiliation(s)
- Jing Zhao
- College of Engineering, China Agricultural University, Beijing 100083, China; State R&D Center for Efficient Production and Comprehensive Utilization of Biobased Gaseous Fuels, Energy Authority, National Development, and Reform Committee (BGFuels), Beijing 100083, China
| | - Maria Westerholm
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, Uppsala BioCenter, Box 7025, SE-750 07 Uppsala, Sweden
| | - Wei Qiao
- College of Engineering, China Agricultural University, Beijing 100083, China; State R&D Center for Efficient Production and Comprehensive Utilization of Biobased Gaseous Fuels, Energy Authority, National Development, and Reform Committee (BGFuels), Beijing 100083, China.
| | - Dongmin Yin
- College of Engineering, China Agricultural University, Beijing 100083, China; State R&D Center for Efficient Production and Comprehensive Utilization of Biobased Gaseous Fuels, Energy Authority, National Development, and Reform Committee (BGFuels), Beijing 100083, China
| | - Shaojie Bi
- College of Engineering, China Agricultural University, Beijing 100083, China; State R&D Center for Efficient Production and Comprehensive Utilization of Biobased Gaseous Fuels, Energy Authority, National Development, and Reform Committee (BGFuels), Beijing 100083, China
| | - Mengmeng Jiang
- College of Engineering, China Agricultural University, Beijing 100083, China; State R&D Center for Efficient Production and Comprehensive Utilization of Biobased Gaseous Fuels, Energy Authority, National Development, and Reform Committee (BGFuels), Beijing 100083, China
| | - Renjie Dong
- College of Engineering, China Agricultural University, Beijing 100083, China; State R&D Center for Efficient Production and Comprehensive Utilization of Biobased Gaseous Fuels, Energy Authority, National Development, and Reform Committee (BGFuels), Beijing 100083, China
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Yang HY, Bao BL, Liu J, Qin Y, Wang YR, Su KZ, Han JC, Mu Y. Temperature dependence of bioelectrochemical CO2 conversion and methane production with a mixed-culture biocathode. Bioelectrochemistry 2018; 119:180-188. [DOI: 10.1016/j.bioelechem.2017.10.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 10/02/2017] [Accepted: 10/02/2017] [Indexed: 12/30/2022]
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Chen Y, Xiao K, Jiang X, Shen N, Zeng RJ, Zhou Y. Long solid retention time (SRT) has minor role in promoting methane production in a 65°C single-stage anaerobic sludge digester. BIORESOURCE TECHNOLOGY 2018; 247:724-729. [PMID: 30060406 DOI: 10.1016/j.biortech.2017.09.153] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 09/19/2017] [Accepted: 09/21/2017] [Indexed: 06/08/2023]
Abstract
In this study, a thermophilic (65°C) single-stage wasted activated sludge (WAS) digester was established and the effects of solid retention time (SRT) on the reactor performance were investigated. The result showed that the optimum SRT was 6days with methane yield of 186.16mL/g VS. It was found that SRT had little effect on the hydrolysis and volatile solids (VS) destruction, and the high temperature employed seemed sufficient to achieve maximum hydrolysis and VS destruction performance. Longer SRT, however, promoted the release of recalcitrant compounds and impaired acidification, leading to the low methane yield. The microbial community analysis revealed that the dominant pathway for methane production was through syntrophic activity of acetate oxidizing bacteria and hydrogenotrophic methanogens while acetoclastic methanogens were absent in the system.
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Affiliation(s)
- Yun Chen
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore 637141, Singapore; CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Keke Xiao
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore 637141, Singapore
| | - Xie Jiang
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore 637141, Singapore
| | - Nan Shen
- School of Environmental Engineering and Science, Yangzhou University, 196 West Huayang Road, Yangzhou, Jiangsu 225127, People's Republic of China
| | - Raymond J Zeng
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Yan Zhou
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore 637141, Singapore; School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore.
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Mulat DG, Huerta SG, Kalyani D, Horn SJ. Enhancing methane production from lignocellulosic biomass by combined steam-explosion pretreatment and bioaugmentation with cellulolytic bacterium Caldicellulosiruptor bescii. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:19. [PMID: 29422947 PMCID: PMC5787918 DOI: 10.1186/s13068-018-1025-z] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Accepted: 01/13/2018] [Indexed: 05/07/2023]
Abstract
BACKGROUND Biogas production from lignocellulosic biomass is generally considered to be challenging due to the recalcitrant nature of this biomass. In this study, the recalcitrance of birch was reduced by applying steam-explosion (SE) pretreatment (210 °C and 10 min). Moreover, bioaugmentation with the cellulolytic bacterium Caldicellulosiruptor bescii was applied to possibly enhance the methane production from steam-exploded birch in an anaerobic digestion (AD) process under thermophilic conditions (62 °C). RESULTS Overall, the combined SE and bioaugmentation enhanced the methane yield up to 140% compared to untreated birch, while SE alone contributed to the major share of methane enhancement by 118%. The best methane improvement of 140% on day 50 was observed in bottles fed with pretreated birch and bioaugmentation with lower dosages of C. bescii (2 and 5% of inoculum volume). The maximum methane production rate also increased from 4-mL CH4/g VS (volatile solids)/day for untreated birch to 9-14-mL CH4/g VS/day for steam-exploded birch with applied bioaugmentation. Bioaugmentation was particularly effective for increasing the initial methane production rate of the pretreated birch yielding 21-44% more methane than the pretreated birch without applied bioaugmentation. The extent of solubilization of the organic matter was increased by more than twofold when combined SE pretreatment and bioaugmentation was used in comparison with the methane production from untreated birch. The beneficial effects of SE and bioaugmentation on methane yield indicated that biomass recalcitrance and hydrolysis step are the limiting factors for efficient AD of lignocellulosic biomass. Microbial community analysis by 16S rRNA amplicon sequencing showed that the microbial community composition was altered by the pretreatment and bioaugmentation processes. Notably, the enhanced methane production by pretreatment and bioaugmentation was well correlated with the increase in abundance of key bacterial and archaeal communities, particularly the hydrolytic bacterium Caldicoprobacter, several members of syntrophic acetate oxidizing bacteria and the hydrogenotrophic Methanothermobacter. CONCLUSION Our findings demonstrate the potential of combined SE and bioaugmentation for enhancing methane production from lignocellulosic biomass.
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Affiliation(s)
- Daniel Girma Mulat
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P.O.Box 5003, 1432 Ås, Norway
| | - Silvia Greses Huerta
- Department of Chemical Engineering, University of Valencia, P.O.Box 46100, Valencia, Spain
| | - Dayanand Kalyani
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P.O.Box 5003, 1432 Ås, Norway
| | - Svein Jarle Horn
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, P.O.Box 5003, 1432 Ås, Norway
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Westerholm M, Müller B, Singh A, Karlsson Lindsjö O, Schnürer A. Detection of novel syntrophic acetate-oxidizing bacteria from biogas processes by continuous acetate enrichment approaches. Microb Biotechnol 2017; 11:680-693. [PMID: 29239113 PMCID: PMC6011928 DOI: 10.1111/1751-7915.13035] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 11/11/2017] [Accepted: 11/12/2017] [Indexed: 11/27/2022] Open
Abstract
To enrich syntrophic acetate‐oxidizing bacteria (SAOB), duplicate chemostats were inoculated with sludge from syntrophic acetate oxidation (SAO)‐dominated systems and continuously supplied with acetate (0.4 or 7.5 g l−1) at high‐ammonia levels. The chemostats were operated under mesophilic (37°C) or thermophilic (52°C) temperature for about six hydraulic retention times (HRT 28 days) and were sampled over time. Irrespective of temperature, a methane content of 64–69% and effluent acetate level of 0.4–1.0 g l−1 were recorded in chemostats fed high acetate. Low methane production in the low‐acetate chemostats indicated that the substrate supply was below the threshold for methanization of acetate via SAO. Novel representatives within the family Clostridiales and genus Syntrophaceticus (class Clostridia) were identified to represent putative SAOB candidates in mesophilic and thermophilic conditions respectively. Known SAOB persisted at low relative abundance in all chemostats. The hydrogenotrophic methanogens Methanoculleus bourgensis (mesophilic) and Methanothermobacter thermautotrophicus (thermophilic) dominated archaeal communities in the high‐acetate chemostats. In line with the restricted methane production in the low‐acetate chemostats, methanogens persisted at considerably lower abundance in these chemostats. These findings strongly indicate involvement in SAO and tolerance to high ammonia levels of the species identified here, and have implications for understanding community function in stressed anaerobic processes.
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Affiliation(s)
- Maria Westerholm
- Uppsala BioCenter, Department of Molecular Sciences, Swedish University of Agricultural Sciences, Box 7025, SE-750 07, Uppsala, Sweden
| | - Bettina Müller
- Uppsala BioCenter, Department of Molecular Sciences, Swedish University of Agricultural Sciences, Box 7025, SE-750 07, Uppsala, Sweden
| | - Abhijeet Singh
- Uppsala BioCenter, Department of Molecular Sciences, Swedish University of Agricultural Sciences, Box 7025, SE-750 07, Uppsala, Sweden
| | - Oskar Karlsson Lindsjö
- Uppsala BioCenter, Department of Molecular Sciences, Swedish University of Agricultural Sciences, Box 7025, SE-750 07, Uppsala, Sweden
| | - Anna Schnürer
- Uppsala BioCenter, Department of Molecular Sciences, Swedish University of Agricultural Sciences, Box 7025, SE-750 07, Uppsala, Sweden
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Wojcieszak M, Pyzik A, Poszytek K, Krawczyk PS, Sobczak A, Lipinski L, Roubinek O, Palige J, Sklodowska A, Drewniak L. Adaptation of Methanogenic Inocula to Anaerobic Digestion of Maize Silage. Front Microbiol 2017; 8:1881. [PMID: 29033919 PMCID: PMC5625012 DOI: 10.3389/fmicb.2017.01881] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 09/14/2017] [Indexed: 11/24/2022] Open
Abstract
A well-balanced microbial consortium is crucial for efficient biogas production. In turn, one of a major factor that influence on the structure of anaerobic digestion (AD) consortium is a source of microorganisms which are used as an inoculum. This study evaluated the influence of inoculum sources (with various origin) on adaptation of a biogas community and the efficiency of the biomethanization of maize silage. As initial inocula for AD of maize silage the samples from: (i) an agricultural biogas plant (ABP) which utilizes maize silage as a main substrate, (ii) cattle slurry (CS), which contain elevated levels of lignocelluloses materials, and (iii) raw sewage sludge (RSS) with low content of plant origin materials were used. The adaptation of methanogenic consortia was monitored during a series of passages, and the functionality of the adapted consortia was verified through start-up operation of AD in two-stage reactors. During the first stages of the adaptation phase, methanogenic consortia occurred very slowly, and only after several passages did the microbial community adapts to allow production of biogas with high methane content. The ABP consortium revealed highest biogas production in the adaptation and in the start-up process. The biodiversity dynamics monitored during adaptation and start-up process showed that community profile changed in a similar direction in three studied consortia. Native communities were very distinct to each other, while at the end of the Phase II of the start-up process microbial diversity profile was similar in all consortia. All adopted bacterial communities were dominated by representatives of Porphyromonadaceae, Rikenellaceae, Ruminococcaceae, and Synergistaceae. A shift from low acetate-preferring acetoclastic Methanosaetaceae (ABP and RSS) and/or hydrogenotrophic Archaea, e.g., Methanomicrobiaceae (CS) prevailing in the inoculum samples to larger populations of high acetate-preferring acetoclastic Methanosarcinaceae was observed by the end of the experiment. As a result, three independent, functional communities that syntrophically produced methane from acetate (primarily) and H2/CO2, methanol and methylamines were adapted. This study provides new insights into the specific process by which different inocula sampled from typical methanogenic environments that are commonly used to initiate industrial installations gradually adapted to allow biogas production from maize silage.
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Affiliation(s)
- Martyna Wojcieszak
- Laboratory of Environmental Pollution Analysis, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Adam Pyzik
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Krzysztof Poszytek
- Laboratory of Environmental Pollution Analysis, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Pawel S Krawczyk
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Adam Sobczak
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland.,Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Leszek Lipinski
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Otton Roubinek
- Institute of Nuclear Chemistry and Technology, Warsaw, Poland
| | - Jacek Palige
- Institute of Nuclear Chemistry and Technology, Warsaw, Poland
| | - Aleksandra Sklodowska
- Laboratory of Environmental Pollution Analysis, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Lukasz Drewniak
- Laboratory of Environmental Pollution Analysis, Faculty of Biology, University of Warsaw, Warsaw, Poland
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Chen Y, Xiao K, Jiang X, Shen N, Zeng RJ, Zhou Y. In-situ sludge pretreatment in a single-stage anaerobic digester. BIORESOURCE TECHNOLOGY 2017; 238:102-108. [PMID: 28433896 DOI: 10.1016/j.biortech.2017.04.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2017] [Revised: 03/31/2017] [Accepted: 04/05/2017] [Indexed: 06/07/2023]
Abstract
This study aimed to develop an in-situ sludge pretreatment method by increasing the temperature from thermophilic to extreme thermophilic condition in a single-stage anaerobic digester. The results revealed that a stable performance was obtained within the temperature range of 55-65°C, and the maximum methane yield of 208.51±13.66mL/g VS was obtained at 65°C. Moreover, the maximum extent of hydrolysis (33%) and acidification (27.1%) was also observed at 65°C. However, further increase of temperature to 70°C did not improve the organic conversion efficiency. Microbial community analysis revealed that Coprothermobacter, highly related to acetate oxidisers, appeared to be the abundant bacterial group at higher temperature. A progressive shift in methanogenic members from Methanosarcina to Methanothermobacter was observed upon increasing the temperature. This work demonstrated single-stage sludge digestion system can be successfully established at high temperature (65°C) with stable performance, which can eliminate the need of conventional thermophilic pretreatment step.
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Affiliation(s)
- Yun Chen
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore 637141, Singapore; CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Keke Xiao
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore 637141, Singapore
| | - Xie Jiang
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore 637141, Singapore
| | - Nan Shen
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore 637141, Singapore
| | - Raymond J Zeng
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Yan Zhou
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore 637141, Singapore; School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore.
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42
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Hao X, Wei J, van Loosdrecht MCM, Cao D. Analysing the mechanisms of sludge digestion enhanced by iron. WATER RESEARCH 2017; 117:58-67. [PMID: 28390236 DOI: 10.1016/j.watres.2017.03.048] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 02/05/2017] [Accepted: 03/23/2017] [Indexed: 06/07/2023]
Abstract
Carbon-neutral operation of wastewater treatment plants (WWTPs) requires enhancing anaerobic digestion (AD) of excess sludge for a higher energy conversion efficiency. Among others, iron has been identified to function on enhancing methane production in AD. As an industrial residual, waste iron scraps (WISs) have been reported as potentially enhancing CH4 production in AD. With this study, the mechanisms of AD enhanced by WISs are analysed in a two-phase process: acidogenic phase (AP) and methanogenic phase (MP). Semi-continuous tests substantially excluded ORP reduction and hydrogen-evolution corrosion induced by WISs in enhancing CH4 production, although WISs (10 g Fe/L) could indeed increase CH4 production by 10.1% and 21.4% when added in AP and MP respectively. Detection on both FISH and enzymatic activities of involved microorganisms revealed that the stimulating effects of WISs on anaerobes (both catabolism and anabolism) could play an important (96.3%) role in enhancing CH4 production, which would facilitate hydrolysis of refractory organics and improvement of electron transport rate (ETR).
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Affiliation(s)
- Xiaodi Hao
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies/Key Laboratory of Urban Stormwater System and Water Environment, Beijing University of Civil Engineering & Architecture, Beijing 100044, PR China.
| | - Jing Wei
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies/Key Laboratory of Urban Stormwater System and Water Environment, Beijing University of Civil Engineering & Architecture, Beijing 100044, PR China
| | - Mark C M van Loosdrecht
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies/Key Laboratory of Urban Stormwater System and Water Environment, Beijing University of Civil Engineering & Architecture, Beijing 100044, PR China; Dept. of Biotechnology, Delft University of Technology, van der Maasweg 9, 2629 HZ Delft, The Netherlands
| | - Daqi Cao
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies/Key Laboratory of Urban Stormwater System and Water Environment, Beijing University of Civil Engineering & Architecture, Beijing 100044, PR China
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43
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Effect of Hydraulic Retention Time on Anaerobic Digestion of Wheat Straw in the Semicontinuous Continuous Stirred-Tank Reactors. BIOMED RESEARCH INTERNATIONAL 2017; 2017:2457805. [PMID: 28589134 PMCID: PMC5446889 DOI: 10.1155/2017/2457805] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 04/06/2017] [Indexed: 11/23/2022]
Abstract
Three semicontinuous continuous stirred-tank reactors (CSTR) operating at mesophilic conditions (35°C) were used to investigate the effect of hydraulic retention time (HRT) on anaerobic digestion of wheat straw. The results showed that the average biogas production with HRT of 20, 40, and 60 days was 46.8, 79.9, and 89.1 mL/g total solid as well as 55.2, 94.3, and 105.2 mL/g volatile solids, respectively. The methane content with HRT of 20 days, from 14.2% to 28.5%, was the lowest among the three reactors. The pH values with HRT of 40 and 60 days were in the acceptable range compared to that with HRT of 20 days. The propionate was dominant in the reactor with HRT of 20 days, inhibiting the activities of methanogens and causing the lower methane content in biogas. The degradation of cellulose, hemicellulose, and crystalline cellulose based on XRD was also strongly influenced by HRTs.
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44
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Hagen LH, Frank JA, Zamanzadeh M, Eijsink VGH, Pope PB, Horn SJ, Arntzen MØ. Quantitative Metaproteomics Highlight the Metabolic Contributions of Uncultured Phylotypes in a Thermophilic Anaerobic Digester. Appl Environ Microbiol 2017; 83:e01955-16. [PMID: 27815274 PMCID: PMC5203625 DOI: 10.1128/aem.01955-16] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 10/31/2016] [Indexed: 01/23/2023] Open
Abstract
In this study, we used multiple meta-omic approaches to characterize the microbial community and the active metabolic pathways of a stable industrial biogas reactor with food waste as the dominant feedstock, operating at thermophilic temperatures (60°C) and elevated levels of free ammonia (367 mg/liter NH3-N). The microbial community was strongly dominated (76% of all 16S rRNA amplicon sequences) by populations closely related to the proteolytic bacterium Coprothermobacter proteolyticus. Multiple Coprothermobacter-affiliated strains were detected, introducing an additional level of complexity seldom explored in biogas studies. Genome reconstructions provided metabolic insight into the microbes that performed biomass deconstruction and fermentation, including the deeply branching phyla Dictyoglomi and Planctomycetes and the candidate phylum "Atribacteria" These biomass degraders were complemented by a synergistic network of microorganisms that convert key fermentation intermediates (fatty acids) via syntrophic interactions with hydrogenotrophic methanogens to ultimately produce methane. Interpretation of the proteomics data also suggested activity of a Methanosaeta phylotype acclimatized to high ammonia levels. In particular, we report multiple novel phylotypes proposed as syntrophic acetate oxidizers, which also exert expression of enzymes needed for both the Wood-Ljungdahl pathway and β-oxidation of fatty acids to acetyl coenzyme A. Such an arrangement differs from known syntrophic oxidizing bacteria and presents an interesting hypothesis for future studies. Collectively, these findings provide increased insight into active metabolic roles of uncultured phylotypes and presents new synergistic relationships, both of which may contribute to the stability of the biogas reactor. IMPORTANCE Biogas production through anaerobic digestion of organic waste provides an attractive source of renewable energy and a sustainable waste management strategy. A comprehensive understanding of the microbial community that drives anaerobic digesters is essential to ensure stable and efficient energy production. Here, we characterize the intricate microbial networks and metabolic pathways in a thermophilic biogas reactor. We discuss the impact of frequently encountered microbial populations as well as the metabolism of newly discovered novel phylotypes that seem to play distinct roles within key microbial stages of anaerobic digestion in this stable high-temperature system. In particular, we draft a metabolic scenario whereby multiple uncultured syntrophic acetate-oxidizing bacteria are capable of syntrophically oxidizing acetate as well as longer-chain fatty acids (via the β-oxidation and Wood-Ljundahl pathways) to hydrogen and carbon dioxide, which methanogens subsequently convert to methane.
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Affiliation(s)
- Live H Hagen
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Jeremy A Frank
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Mirzaman Zamanzadeh
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Vincent G H Eijsink
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Phillip B Pope
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Svein J Horn
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Magnus Ø Arntzen
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), Ås, Norway
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45
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Manzoor S, Bongcam-Rudloff E, Schnürer A, Müller B. Genome-Guided Analysis and Whole Transcriptome Profiling of the Mesophilic Syntrophic Acetate Oxidising Bacterium Syntrophaceticus schinkii. PLoS One 2016; 11:e0166520. [PMID: 27851830 PMCID: PMC5113046 DOI: 10.1371/journal.pone.0166520] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 10/31/2016] [Indexed: 01/29/2023] Open
Abstract
Syntrophaceticus schinkii is a mesophilic, anaerobic bacterium capable of oxidising acetate to CO2 and H2 in intimate association with a methanogenic partner, a syntrophic relationship which operates close to the energetic limits of microbial life. Syntrophaceticus schinkii has been identified as a key organism in engineered methane-producing processes relying on syntrophic acetate oxidation as the main methane-producing pathway. However, due to strict cultivation requirements and difficulties in reconstituting the thermodynamically unfavourable acetate oxidation, the physiology of this functional group is poorly understood. Genome-guided and whole transcriptome analyses performed in the present study provide new insights into habitat adaptation, syntrophic acetate oxidation and energy conservation. The working draft genome of Syntrophaceticus schinkii indicates limited metabolic capacities, with lack of organic nutrient uptake systems, chemotactic machineries, carbon catabolite repression and incomplete biosynthesis pathways. Ech hydrogenase, [FeFe] hydrogenases, [NiFe] hydrogenases, F1F0-ATP synthase and membrane-bound and cytoplasmic formate dehydrogenases were found clearly expressed, whereas Rnf and a predicted oxidoreductase/heterodisulphide reductase complex, both found encoded in the genome, were not expressed under syntrophic growth condition. A transporter sharing similarities to the high-affinity acetate transporters of aceticlastic methanogens was also found expressed, suggesting that Syntrophaceticus schinkii can potentially compete with methanogens for acetate. Acetate oxidation seems to proceed via the Wood-Ljungdahl pathway as all genes involved in this pathway were highly expressed. This study shows that Syntrophaceticus schinkii is a highly specialised, habitat-adapted organism relying on syntrophic acetate oxidation rather than metabolic versatility. By expanding its complement of respiratory complexes, it might overcome limiting bioenergetic barriers, and drive efficient energy conservation from reactions operating close to the thermodynamic equilibrium, which might enable S. schinkii to occupy the same niche as the aceticlastic methanogens. The knowledge gained here will help specify process conditions supporting efficient and robust biogas production and will help identify mechanisms important for the syntrophic lifestyle.
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Affiliation(s)
- Shahid Manzoor
- Department of Information Technology, University of the Punjab, Lahore, Pakistan
| | - Erik Bongcam-Rudloff
- Department of Animal Breeding and Genetics, Swedish University of Agricultural Science, SLU-Global Bioinformatics Centre, Uppsala, SE 750 07, Sweden
| | - Anna Schnürer
- Department of Microbiology, Swedish University of Agricultural Sciences, BioCenter, Uppsala, SE 750 07, Sweden
| | - Bettina Müller
- Department of Microbiology, Swedish University of Agricultural Sciences, BioCenter, Uppsala, SE 750 07, Sweden
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46
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Chen Y, Wang T, Shen N, Zhang F, Zeng RJ. High-purity propionate production from glycerol in mixed culture fermentation. BIORESOURCE TECHNOLOGY 2016; 219:659-667. [PMID: 27544916 DOI: 10.1016/j.biortech.2016.08.026] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Revised: 08/08/2016] [Accepted: 08/09/2016] [Indexed: 06/06/2023]
Abstract
High-purity propionate production from glycerol in mixed culture fermentation (MCF) induced by high ammonium concentration was investigated. Fed-batch experiments revealed that higher ammonium concentration (>2.9g/L) had simultaneous negative effects on acetate and propionate degradation. Propionate production and yield was up to 22.6g/L and 0.45g COD/g COD glycerol, respectively, with a purity of 96%. Sequential batch experiments demonstrated that the yields of propionate were 0.3±0.05, 0.32±0.01, and 0.34±0.03g COD/g COD at a glycerol concentration of 2.78, 4.38, and 5.56g/L, respectively, and the purity of propionate was 91-100%. Microbial community analysis showed that the phylum Firmicutes dominated the bacterial community at different glycerol concentrations. However, the Methanosaeta population decreased from 46% to 6% when glycerol concentration increased from 2.78 to 5.56g/L, resulting in lower acetate degradation rate. Thus, the present study might provide an alternative option for the production of propionate from glycerol via MCF.
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Affiliation(s)
- Yun Chen
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Ting Wang
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Nan Shen
- School of Environmental Engineering and Science, Yangzhou University, 196 West Huayang Road, Yangzhou, Jiangsu 225127, People's Republic of China
| | - Fang Zhang
- Hebei Key Laboratory of Applied Chemistry, School of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao, Hebei 066004, People's Republic of China
| | - Raymond J Zeng
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China; Collaborative Innovation Center of Suzhou Nano Science and Technology, Suzhou, Jiangsu 215123, People's Republic of China.
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47
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Gehring T, Niedermayr A, Berzio S, Immenhauser A, Wichern M, Lübken M. Determination of the fractions of syntrophically oxidized acetate in a mesophilic methanogenic reactor through an (12)C and (13)C isotope-based kinetic model. WATER RESEARCH 2016; 102:362-373. [PMID: 27390036 DOI: 10.1016/j.watres.2016.06.038] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2016] [Revised: 06/15/2016] [Accepted: 06/16/2016] [Indexed: 06/06/2023]
Abstract
In order to accurately describe the carbon flow in anaerobic digestion processes, this work investigates the acetate degradation pathways through the use of stable carbon isotope analysis and a mathematical model. Batch assays using labeled (13)C acetate were employed to distinguish the acetate consumption through methanogenic Archaea and acetate-oxidizing Bacteria. Suspended and sessile biomass, with over 400 days of retention time, from a mesophilic (36.5 °C) upflow anaerobic filter was used as inocula in these assays. A three-process model for acetoclastic methanogenesis and syntrophic acetate oxidation (SAO) was developed to allow for a precise quantification of the SAO contribution. The model distinguishes carbon atoms in light and heavy isotopes, (12)C and (13)C, respectively, which permitted the simulation of the isotope ratios variation in addition to gas production, gas composition and acetate concentrations. The model indicated oxidized fractions of acetate between 7 and 18%. Due to the low free ammonia inhibition potential for the acetoclastic methanogens in these assays these findings point to the biomass retention times as a driven factor for the SAO pathway. The isotope-based kinetic model developed here also describes the δ(13)C variations in unlabeled assays accurately and has the potential to determine biological (13)C fractionation factors.
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Affiliation(s)
- Tito Gehring
- Institute of Urban Water Management and Environmental Engineering, Ruhr-Universität Bochum, Germany.
| | - Andrea Niedermayr
- Institute of Geology, Mineralogy and Geophysics, Ruhr-Universität Bochum, Germany.
| | - Stephan Berzio
- Institute of Urban Water Management and Environmental Engineering, Ruhr-Universität Bochum, Germany.
| | - Adrian Immenhauser
- Institute of Geology, Mineralogy and Geophysics, Ruhr-Universität Bochum, Germany.
| | - Marc Wichern
- Institute of Urban Water Management and Environmental Engineering, Ruhr-Universität Bochum, Germany.
| | - Manfred Lübken
- Institute of Urban Water Management and Environmental Engineering, Ruhr-Universität Bochum, Germany.
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48
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Chen Y, Zhang F, Wang T, Shen N, Yu ZW, Zeng RJ. Hydraulic retention time affects stable acetate production from tofu processing wastewater in extreme-thermophilic (70°C) mixed culture fermentation. BIORESOURCE TECHNOLOGY 2016; 216:722-728. [PMID: 27295249 DOI: 10.1016/j.biortech.2016.06.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 06/02/2016] [Accepted: 06/03/2016] [Indexed: 06/06/2023]
Abstract
Acetate is an important industrial chemical and its production from wastes via mixed culture fermentation (MCF) is economic. In this work, the effect of hydraulic retention time (HRT) on acetate production from tofu processing wastewater (TPW) in extreme-thermophilic (70°C) MCF was first investigated. It was found that long HRT (>3days) could lead to less acetate production while stable acetate production was achieved at short HRT (3days) with the yield of 0.57g-COD/g-CODTPW. The microbial community analysis showed that hydrogenotrophic methanogens (mainly Methanothermobacter) occupied up to 90% of archaea at both HRTs of 3 and 5days. However, Coprothermobacter, the main acetate-degraders, decreased from 35.74% to 10.58% of bacteria when HRT decreased from 5 to 3days, supporting the aggravation of syntrophic acetate oxidation in long HRT. This work demonstrated that HRT was a crucial factor to maintain stable acetate production from TPW in extreme-thermophilic MCF.
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Affiliation(s)
- Yun Chen
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Fang Zhang
- Hebei Key Laboratory of Applied Chemistry, School of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao, Hebei 066004, People's Republic of China
| | - Ting Wang
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Nan Shen
- School of Environmental Engineering and Science, Yangzhou University, 196 West Huayang Road, Yangzhou, Jiangsu 225127, People's Republic of China
| | - Zhong-Wei Yu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Raymond J Zeng
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China.
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Ho D, Jensen P, Gutierrez-Zamora ML, Beckmann S, Manefield M, Batstone D. High-rate, High Temperature Acetotrophic Methanogenesis Governed by a Three Population Consortium in Anaerobic Bioreactors. PLoS One 2016; 11:e0159760. [PMID: 27490246 PMCID: PMC4973872 DOI: 10.1371/journal.pone.0159760] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 07/07/2016] [Indexed: 11/18/2022] Open
Abstract
A combination of acetate oxidation and acetoclastic methanogenesis has been previously identified to enable high-rate methanogenesis at high temperatures (55 to 65°C), but this capability had not been linked to any key organisms. This study combined RNA–stable isotope probing on 13C-labelled acetate and 16S amplicon sequencing to identify the active micro-organisms involved in high-rate methanogenesis. Active biomass was harvested from three bench-scale thermophilic bioreactors treating waste activated sludge at 55, 60 and 65°C, and fed with 13-C labelled and 12C-unlabelled acetate. Acetate uptake and cumulative methane production were determined and kinetic parameters were estimated using model-based analysis. Pyrosequencing performed on 13C- enriched samples indicated that organisms accumulating labelled carbon were Coprothermobacter (all temperatures between 55 and 65°C), acetoclastic Methanosarcina (55 to 60°C) and hydrogenotrophic Methanothermobacter (60 to 65°C). The increased relative abundance of Coprothermobacter with increased temperature corresponding with a shift to syntrophic acetate oxidation identified this as a potentially key oxidiser. Methanosarcina likely acts as both a hydrogen utilising and acetoclastic methanogen at 55°C, and is replaced by Methanothermobacter as a hydrogen utiliser at higher temperatures.
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MESH Headings
- Acetates/chemistry
- Acetates/metabolism
- Biomass
- Bioreactors
- Carbon Isotopes
- DNA, Bacterial/chemistry
- DNA, Bacterial/isolation & purification
- DNA, Bacterial/metabolism
- Euryarchaeota/classification
- Euryarchaeota/genetics
- Euryarchaeota/growth & development
- Isotope Labeling
- Kinetics
- Methane/biosynthesis
- Methanosarcina/classification
- Methanosarcina/genetics
- Methanosarcina/growth & development
- Oxidation-Reduction
- Phylogeny
- RNA, Ribosomal, 16S/chemistry
- RNA, Ribosomal, 16S/genetics
- RNA, Ribosomal, 16S/metabolism
- Sequence Analysis, DNA
- Sewage/microbiology
- Temperature
- Thermoanaerobacter/classification
- Thermoanaerobacter/genetics
- Thermoanaerobacter/growth & development
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Affiliation(s)
- Dang Ho
- Advanced Water Management Centre, The University of Queensland, St Lucia, Queensland, Australia
| | - Paul Jensen
- Advanced Water Management Centre, The University of Queensland, St Lucia, Queensland, Australia
| | - Maria-Luisa Gutierrez-Zamora
- Centre for Marine BioInnovation, School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Kensington, New South Wales, Australia
| | - Sabrina Beckmann
- Centre for Marine BioInnovation, School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Kensington, New South Wales, Australia
| | - Mike Manefield
- Centre for Marine BioInnovation, School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Kensington, New South Wales, Australia
| | - Damien Batstone
- Advanced Water Management Centre, The University of Queensland, St Lucia, Queensland, Australia
- * E-mail:
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50
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Kim J, Lee C. Response of a continuous anaerobic digester to temperature transitions: A critical range for restructuring the microbial community structure and function. WATER RESEARCH 2016; 89:241-51. [PMID: 26689661 DOI: 10.1016/j.watres.2015.11.060] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Revised: 11/24/2015] [Accepted: 11/26/2015] [Indexed: 05/03/2023]
Abstract
Temperature is a crucial factor that significantly influences the microbial activity and so the methanation performance of an anaerobic digestion (AD) process. Therefore, how to control the operating temperature for optimal activity of the microbes involved is a key to stable AD. This study examined the response of a continuous anaerobic reactor to a series of temperature shifts over a wide range of 35-65 °C using a dairy-processing byproduct as model wastewater. During the long-term experiment for approximately 16 months, the reactor was subjected to stepwise temperature increases by 5 °C at a fixed HRT of 15 days. The reactor showed stable performance within the temperature range of 35-45 °C, with the methane production rate and yield being maximum at 45 °C (18% and 26% greater, respectively, than at 35 °C). However, the subsequent increase to 50 °C induced a sudden performance deterioration with a complete cessation of methane recovery, indicating that the temperature range between 45 °C and 50 °C had a critical impact on the transition of the reactor's methanogenic activity from mesophilic to thermophilic. This serious process perturbation was associated with a severe restructuring of the reactor microbial community structure, particularly of methanogens, quantitatively as well as qualitatively. Once restored by interrupted feeding for about two months, the reactor maintained fairly stable performance under thermophilic conditions until it was upset again at 65 °C. Interestingly, in contrast to most previous reports, hydrogenotrophs largely dominated the methanogen community at mesophilic temperatures while acetotrophs emerged as a major group at thermophilic temperature. This implies that the primary methanogenesis route of the reactor shifted from hydrogen- to acetate-utilizing pathways with the temperature shifts from mesophilic to thermophilic temperatures. Our observations suggest that a mesophilic digester may not need to be cooled at up to 45 °C in case of undesired temperature rise, for example, by excessive self-heating, which offers a possibility to reduce operating costs.
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Affiliation(s)
- Jaai Kim
- School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan 689-798, Republic of Korea
| | - Changsoo Lee
- School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan 689-798, Republic of Korea.
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