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Zhang X, Jiao P, Wang Y, Dai Y, Zhang M, Wu P, Ma L. Optimizing anaerobic digestion: Benefits of mild temperature transition from thermophilic to mesophilic conditions. ENVIRONMENTAL SCIENCE AND ECOTECHNOLOGY 2024; 21:100440. [PMID: 38993655 PMCID: PMC11237690 DOI: 10.1016/j.ese.2024.100440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 06/09/2024] [Accepted: 06/10/2024] [Indexed: 07/13/2024]
Abstract
Anaerobic digestion (AD) plays a significant role in renewable energy recovery. Upgrading AD from thermophilic (50-57 °C) to mesophilic (30-38 °C) conditions to enhance process stability and reduce energy input remains challenging due to the high sensitivity of thermophilic microbiomes to temperature fluctuations. Here we compare the effects of two decreasing-temperature modes from 55 to 35 °C on cell viability, microbial dynamics, and interspecies interactions. A sharp transition (ST) is a one-step transition by 20 °C d-1, while a mild transition (MT) is a stepwise transition by 1 °C d-1. We find a greater decrease in methane production with ST (88.8%) compared to MT (38.9%) during the transition period. ST mode overproduced reactive oxygen species by 1.6-fold, increased membrane permeability by 2.2-fold, and downregulated microbial energy metabolism by 25.1%, leading to increased apoptosis of anaerobes by 1.9-fold and release of intracellular substances by 2.9-fold, further constraining methanogenesis. The higher (1.6 vs. 1.1 copies per gyrA) metabolic activity of acetate-dependent methanogenesis implied more efficient methane production in a steady mesophilic, MT-mediated system. Metagenomic binning and network analyses indicated that ST induced dysbiosis in keystone species and greatly enhanced microbial functional redundancy, causing loss of microbial syntrophic interactions and redundant metabolic pathways. In contrast, the greater microbial interconnections (average degrees 44.9 vs. 22.1) in MT at a steady mesophilic state suggested that MT could better maintain necessary system functionality and stability through microbial syntrophy or specialized pathways. Adopting MT to transform thermophilic digesters into mesophilic digesters is feasible and could potentially enhance the further optimization and broader application of practical anaerobic engineering.
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Affiliation(s)
- Xingxing Zhang
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, 200241, China
| | - Pengbo Jiao
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, 200241, China
| | - Yiwei Wang
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, 200241, China
| | - Yinying Dai
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, 200241, China
| | - Ming Zhang
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, 200241, China
| | - Peng Wu
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215009, China
| | - Liping Ma
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, 200241, China
- Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area, Ministry of Natural Resources, Shanghai, 200062, China
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Zhang X, Ma L, Zhang XX. Neglected risks of enhanced antimicrobial resistance and pathogenicity in anaerobic digestion during transition from thermophilic to mesophilic. JOURNAL OF HAZARDOUS MATERIALS 2024; 475:134886. [PMID: 38878435 DOI: 10.1016/j.jhazmat.2024.134886] [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: 02/09/2024] [Revised: 06/05/2024] [Accepted: 06/10/2024] [Indexed: 06/27/2024]
Abstract
Minimization of antibiotic resistance genes (ARGs) and potential pathogenic antibiotic-resistant bacteria (PARB) during anaerobic digestion (AD) is significantly impacted by temperature. However, knowledge on how ARGs and PARB respond to temperature transition from thermophilic to mesophilic is limited. Here, we combined metagenomic-based with culture-based approaches and revealed the risks of antimicrobial resistance and pathogenicity during transition from 55 °C to 35 °C for AD, with strategies of sharp (ST, one-step by 20 °C/d) and mild (MT, step-wise by 1 °C/d). Results indicated a lower decrease in methane production with MT (by 38.9%) than ST (by 88.8%). Phenotypic assays characterized a significant propagation of multi-resistant lactose-fermenting Enterobacteriaceae and indicator pathogens after both transitions, especially via ST. Further genomic evidence indicated a significant increase of ARGs (29.4-fold), virulence factor genes (1.8-fold) and PARB (65.3-fold) after ST, while slight enrichment via MT. Bacterial succession and enhanced horizontal transfer mediated by mobile genetic elements promoted ARG propagation in AD during transition, which was synchronously exacerbated through horizontal transfer mechanisms mediated by cellular physiological responses (oxidative stress, membrane permeability, bacterial conjugation and transformation) and co-selection mechanisms of biomethanation metabolic functions (acidogenesis and acetogenesis). This study reveals temperature-dependent resistome and pathogenicity development in AD, facilitating microbial risk control.
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Affiliation(s)
- Xingxing Zhang
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China
| | - Liping Ma
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China; Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area, Ministry of Natural Resources, Shanghai 200062, PR China.
| | - Xu-Xiang Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China
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Hmaissia A, Bareha Y, Vaneeckhaute C. Correlations and impact of anaerobic digestion operating parameters on the start-up duration: Database construction for robust start-up guidelines. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 359:121068. [PMID: 38728989 DOI: 10.1016/j.jenvman.2024.121068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 04/17/2024] [Accepted: 04/29/2024] [Indexed: 05/12/2024]
Abstract
Anaerobic digestion (AD) has become a popular technique for organic waste management while offering economic and environmental advantages. As AD becomes increasingly prevalent worldwide, research efforts are primarily focused on optimizing its processes. During the operation of AD systems, the occurrence of unstable events is inevitable. So far, numerous conclusions have been drawn from full and lab-scale studies regarding the driving factors of start-up perturbations. However, the lack of standardized practices reported in start-up studies raises concerns about the comparability and reliability of obtained data. This study aims to develop a knowledge database and investigate the possibility of applying machine learning techniques on experimentation-extracted data to assist start-up planning and monitoring. Thus, a standardized database referencing 75 cases of start-up of one-stage wet continuously-stirred tank reactors (CSTR) processing agricultural, industrial, or municipal organic effluent in mono-digestion from 31 studies was constructed. 10 % of the total observations included in this database concern failed start-up experiments. Then, correlations between the parameters and their impacts on the start-up duration were studied using multivariate analysis and a model-based ranking methodology. Insights into trends of choices were highlighted through the correlation analysis of the database. As such, scenarios favoring short start-up duration were found to involve relatively low retention times (average initial and final hydraulic retention times, (HRTi) and (HRTf) of 26.25 and 20.6 days, respectively), high mean organic loading rates (average OLRmean of 5.24 g VS·d-1·L -1) and the processing of highly fermentable substrates (average feed volatile solids (VSfeed) of 81.35 g L-1). The model-based ranking of AD parameters demonstrated that the HRTf, the VSfeed, and the target temperature (Tf) have the strongest impact on the start-up duration, receiving the highest relative scores among the evaluated AD parameters. The database could serve as a reference for comparison purposes of future start-up studies allowing the identification of factors that should be closely controlled.
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Affiliation(s)
- Amal Hmaissia
- BioEngine Research Team on Green Process Engineering and Biorefineries, Chemical Engineering Department, Université Laval, Pavillon Adrien-Pouliot 1065, av. de la Médecine, Québec, QC, Canada; CentrEau, Centre de Recherche sur l'eau, Université Laval, 1065 Avenue de la Médecine, Québec, QC, G1V 0A6, Canada.
| | - Younes Bareha
- BioEngine Research Team on Green Process Engineering and Biorefineries, Chemical Engineering Department, Université Laval, Pavillon Adrien-Pouliot 1065, av. de la Médecine, Québec, QC, Canada; CentrEau, Centre de Recherche sur l'eau, Université Laval, 1065 Avenue de la Médecine, Québec, QC, G1V 0A6, Canada.
| | - Céline Vaneeckhaute
- BioEngine Research Team on Green Process Engineering and Biorefineries, Chemical Engineering Department, Université Laval, Pavillon Adrien-Pouliot 1065, av. de la Médecine, Québec, QC, Canada; CentrEau, Centre de Recherche sur l'eau, Université Laval, 1065 Avenue de la Médecine, Québec, QC, G1V 0A6, Canada.
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Alam M, Dhar BR. Boosting thermophilic anaerobic digestion with conductive materials: Current outlook and future prospects. CHEMOSPHERE 2023; 343:140175. [PMID: 37714472 DOI: 10.1016/j.chemosphere.2023.140175] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 08/15/2023] [Accepted: 09/12/2023] [Indexed: 09/17/2023]
Abstract
Thermophilic anaerobic digestion (TAD) can provide superior process kinetics, higher methane yields, and more pathogen destruction than mesophilic anaerobic digestion (MAD). However, the broader application of TAD is still very limited, mainly due to process instabilities such as the accumulation of volatile fatty acids and ammonia inhibition in the digesters. An emerging technique to overcome the process disturbances in TAD and enhance the methane production rate is to add conductive materials (CMs) to the digester. Recent studies have revealed that CMs can promote direct interspecies electron transfer (DIET) among the microbial community, increasing the TAD performance. CMs exhibited a high potential for alleviating the accumulation of volatile fatty acids and inhibition caused by high ammonia levels. However, the types, properties, sources, and dosage of CMs can influence the process outcomes significantly, along with other process parameters such as the organic loading rates and the type of feedstocks. Therefore, it is imperative to critically review the recent research to understand the impacts of using different CMs in TAD. This review paper discusses the types and properties of CMs applied in TAD and the mechanisms of how they influence methanogenesis, digester start-up time, process disturbances, microbial community, and biogas desulfurization. The engineering challenges for industrial-scale applications and environmental risks were also discussed. Finally, critical research gaps have been identified to provide a framework for future research.
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Affiliation(s)
- Monisha Alam
- Civil and Environmental Engineering, University of Alberta, 116 Street NW, Edmonton, AB, T6G 1H9, Canada
| | - Bipro Ranjan Dhar
- Civil and Environmental Engineering, University of Alberta, 116 Street NW, Edmonton, AB, T6G 1H9, Canada.
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Yan X, Deng P, Ding T, Zhang Z, Li X, Wu Z. Effect of Temperature on Anaerobic Fermentation of Poplar Ethanol Wastewater: Performance and Microbial Communities. ACS OMEGA 2023; 8:5486-5496. [PMID: 36816634 PMCID: PMC9933484 DOI: 10.1021/acsomega.2c06721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 01/16/2023] [Indexed: 06/18/2023]
Abstract
Temperature plays an important role in anaerobic digestion (AD), and different substrates have different optimum temperatures in AD. However, the effect of temperature on the performance of AD when cellulosic ethanol wastewater was used as a substrate was rarely reported. Therefore, the digestion characteristics of cellulosic ethanol wastewater at 25, 35, 45, and 55 °C were investigated, and the microbial communities of the sludge sample were analyzed after fermentation. The results showed that the cumulative methane production was the highest at 55 °C, 906.40 ± 50.67 mL/g VS, which was 81.06, 72.42, and 13.33% higher than that at 25, 35, and 45 °C, respectively. The content of methane was 68.13, 49.26, 70.46, and 85.84% at the terminal period of fermentation at temperatures of 25, 35, 45, and 55 °C, respectively. The testing of volatile fatty acids (VFAs) indicated that the accumulation of VFAs did not occur when the fermentation was carried out at 25, 35, and 45 °C; however, the VFA content at 55 °C was much larger than that in the three groups (25, 35, and 45 °C), and the ratio of propionic acid to acetic acid was larger than 1.4 at the late stage of fermentation, so it inhibited the fermentation. The diversity of the microbial community indicated that the floral structure and metabolic pathway of fermentation were alike at 25 and 35 °C. Firmicutes and Proteobacteria were the main flora covering the 25-55 °C-based phylum or below it. The relative abundance of Methanosaeta was the highest when fermentation temperatures were 25 and 35 °C; however, its relative abundance decreased sharply and the relative abundance of Methanosarcina increased substantially when the temperature increased from 35 to 45 °C, which indicated that Methanosarcina can exist in higher temperatures. At the same time, hydrogenotrophic methanogens such as Methanoculleus and Methanothermobacter were dominant when fermentation temperatures were 45 and 55 °C, which indicated that the metabolic pathway changed from acetoclastic methanogenesis to hydrogenotrophic methanogenesis.
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Schmautz Z, Walser JC, Espinal CA, Gartmann F, Scott B, Pothier JF, Frossard E, Junge R, Smits THM. Microbial diversity across compartments in an aquaponic system and its connection to the nitrogen cycle. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 852:158426. [PMID: 36055492 DOI: 10.1016/j.scitotenv.2022.158426] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 08/25/2022] [Accepted: 08/27/2022] [Indexed: 06/15/2023]
Abstract
Aquaponics combines hydroponic crop production with recirculating aquaculture. These systems comprise various compartments (fish tank, biofilter, sump, hydroponic table, radial flow settler and anaerobic digester), each with their own specific environmental pressures, which trigger the formation of unique microbial communities. Triplicated aquaponic systems were used to investigate the microbial community composition during three lettuce growing cycles. The sampling of individual compartments allowed community patterns to be generated using amplicon sequencing of bacterial and archaeal 16S rRNA genes. Nitrifying bacteria were identified in the hydroponic compartments, indicating that these compartments may play a larger role than previously thought in the system's nitrogen cycle. In addition to the observed temporal changes in community compositions within the anaerobic compartment, more archaeal reads were obtained from sludge samples than from the aerobic part of the system. Lower bacterial diversity was observed in fresh fish feces, where a highly discrete gut flora composition was seen. Finally, the most pronounced differences in microbial community compositions were observed between the aerobic and anaerobic loops of the system, with unique bacterial compositions in each individual compartment.
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Affiliation(s)
- Zala Schmautz
- Ecological Engineering Centre, Institute of Natural Resource Sciences, Zurich University of Applied Sciences, Wädenswil, Switzerland; Group of Plant Nutrition, Institute of Agricultural Sciences, ETH Zurich, Lindau, Switzerland..
| | | | | | - Florentina Gartmann
- Ecological Engineering Centre, Institute of Natural Resource Sciences, Zurich University of Applied Sciences, Wädenswil, Switzerland
| | - Ben Scott
- Ecological Engineering Centre, Institute of Natural Resource Sciences, Zurich University of Applied Sciences, Wädenswil, Switzerland
| | - Joël F Pothier
- Environmental Genomics and Systems Biology Research Group, Institute of Natural Resource Sciences, Zurich University of Applied Sciences, Wädenswil, Switzerland
| | - Emmanuel Frossard
- Group of Plant Nutrition, Institute of Agricultural Sciences, ETH Zurich, Lindau, Switzerland
| | - Ranka Junge
- Ecological Engineering Centre, Institute of Natural Resource Sciences, Zurich University of Applied Sciences, Wädenswil, Switzerland
| | - Theo H M Smits
- Environmental Genomics and Systems Biology Research Group, Institute of Natural Resource Sciences, Zurich University of Applied Sciences, Wädenswil, Switzerland
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Chang Bejarano A, Champagne P. Optimization of biogas production during start-up with electrode-assisted anaerobic digestion. CHEMOSPHERE 2022; 302:134739. [PMID: 35489453 DOI: 10.1016/j.chemosphere.2022.134739] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2021] [Revised: 04/01/2022] [Accepted: 04/23/2022] [Indexed: 05/23/2023]
Abstract
To better understand anaerobic digestion (AD) conditions during start-up, a series of batch and bench-scale studies were conducted to investigate conditions affecting the performance of the anaerobic reactors, including pH fluctuations, ammonia inhibition, and bioaugmentation. Capacitive soil moisture sensors were placed inside the AD reactors to provide near real-time microbial monitoring under experimental batch conditions and to create a microbial electrolysis cell (MEC) environment. After an eight-day digestion process at 40 °C, the capacitive soil moisture sensors performed as a rudimentary microbial activity tracking device. However, the electrodes had a statistically significant impact on biogas production with a small potential 0.8 V having a stabilizing effect on AD at 40 °C during start-up. Furthermore, electrode-assisted AD noted a biogas output 63.7% higher than the conventional AD without electrodes. Conversely, the bioaugmented electrode-assisted AD showed a 7% increase in biogas volume when compared to the non-bioaugmented batch.
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Affiliation(s)
- Alan Chang Bejarano
- Civil Engineering, Queen's University & Beaty Water Research Centre, 69 Union St., Kingston, Ontario, K7L 3N6, Canada
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Zhang L, Gong X, Xu R, Guo K, Wang L, Zhou Y. Responses of mesophilic anaerobic sludge microbiota to thermophilic conditions: Implications for start-up and operation of thermophilic THP-AD systems. WATER RESEARCH 2022; 216:118332. [PMID: 35364350 DOI: 10.1016/j.watres.2022.118332] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 02/20/2022] [Accepted: 03/18/2022] [Indexed: 06/14/2023]
Abstract
Anaerobic digestion (AD) has been widely employed for wastewater and organic waste treatment, in which methanogenesis is highly driven by close microbial interactions among intricate microbial communities. However, the ecological processes underpinning the community assembly that support methanogenesis in such engineered ecosystems remain largely unknown, especially when exposed to challenging circumstances (e.g., high temperature, ammonium content). Here, eight AD bioreactors were seeded with four different inocula (two from full-scale mesophilic AD systems and the other two from lab-scale mesophilic AD systems), and were operated under thermophilic conditions (55 °C) for treating thermal hydrolysis process (THP) pre-treated waste activated sludge to investigate how mesophilic community responds to thermophilic conditions during the long-term cultivation. Results showed that the inocula collected from the full-scale systems were more resilient than that from the lab-scale systems, which may be primarily attributed to indigenous robust methanogens. As a result, the former efficiently generated methane which was predominantly contributed by Methanothermobacter and Methanosarcina (healthy AD ecosystem), while methanogenic activity was remarkably prohibited in the latter (dysfunctional AD ecosystem). Thermophilic environment was a strong selection force, resulting in the convergence of microbial communities in both the healthy and dysfunctional AD ecosystems. Deterministic processes predominated the community assembly regardless of AD ecosystem function, but stronger influences of stochastic processes were observed in dysfunctional AD ecosystems, which was likely attributable from the stronger effect of immigrants from the feedstock. As indicated by molecular ecological network analysis, the microbial network structures in the healthy AD ecosystems were more stable than those in the dysfunctional AD ecosystems. Although keystone taxa were different among the bioreactors, most of which played vital roles in organic hydrolysis/fermentation. To sum up, this study greatly improved our understanding of the relationships between microbiological traits and AD ecosystem function under thermophilic conditions, which could provide useful information to guide thermophilic AD (e.g., THP-AD) start-up and health diagnosis during operation.
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Affiliation(s)
- Liang Zhang
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore
| | - Xianzhe Gong
- Institute of Marine Science and Technology, Shandong University, Qingdao, Shandong 266237, China
| | - Ronghua Xu
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou, China
| | - Kun Guo
- School of Ecological and Environmental Sciences, East China Normal University, Shanghai, China
| | - Li Wang
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore
| | - Yan Zhou
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore 637141, Singapore; School of Civil and Environmental Engineering, Nanyang Technological University, Singapore 639798, Singapore.
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Gómez-Quiroga X, Aboudi K, Álvarez-Gallego CJ, Romero-García LI. Successful and stable operation of anaerobic thermophilic co-digestion of sun-dried sugar beet pulp and cow manure under short hydraulic retention time. CHEMOSPHERE 2022; 293:133484. [PMID: 34990719 DOI: 10.1016/j.chemosphere.2021.133484] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 12/02/2021] [Accepted: 12/29/2021] [Indexed: 06/14/2023]
Abstract
This work consists of a long-term (621 days) experimental study about biogas production from sun dried sugar beet pulp and cow manure. Thermophilic (55 °C) anaerobic co-digestion was performed in semi-continuous reactors, testing ten hydraulic retention times (30-3 days) (HRTs) and organic loading rates (2-24 gVS/Lreactor∙d) (OLRs). Results showed that the best global system performance (regarding stability, biogas production, and organic matter removal) was achieved at an HRT as short as 5 days (OLR of 12.47 gVS/Lreactor∙d) with a biogas yield of 315 mL/gVSadded. The gradual OLR increase allowed system control and time-appropriate intervention, avoiding irreversible process disturbances and maintaining admissible acidity/alkalinity ratios (<0.8) for HRTs ranging from 30 to 4 days. The accumulation of acetic acid was the main cause of the process disturbance observed at short HRTs. It was deduced that for the HRT of 3 days, the methane productivity was mainly owing to the hydrogen-utilizing methanogens pathway. This research clearly shows how an adequate combination of agro-industrial wastes and livestock manure could be processed by anaerobic co-digestion in short HRTs with great efficiency and stability and deepens in the understanding of the start-up, stability and optimization of the co-digestion.
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Affiliation(s)
- Xiomara Gómez-Quiroga
- Department of Chemical Engineering and Food Technology, Faculty of Science, University of Cádiz - International Campus of Excellence (ceiA3), P.O. Box No 40, 11510, Puerto Real, Cádiz, Spain
| | - Kaoutar Aboudi
- Department of Chemical Engineering and Food Technology, Faculty of Science, University of Cádiz - International Campus of Excellence (ceiA3), P.O. Box No 40, 11510, Puerto Real, Cádiz, Spain
| | - Carlos José Álvarez-Gallego
- Department of Chemical Engineering and Food Technology, Faculty of Science, University of Cádiz - International Campus of Excellence (ceiA3), P.O. Box No 40, 11510, Puerto Real, Cádiz, Spain.
| | - Luis Isidoro Romero-García
- Department of Chemical Engineering and Food Technology, Faculty of Science, University of Cádiz - International Campus of Excellence (ceiA3), P.O. Box No 40, 11510, Puerto Real, Cádiz, Spain
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Kong Z, Li L, Wu J, Rong C, Wang T, Chen R, Sano D, Li YY. Unveiling the characterization and development of prokaryotic community during the start-up and long-term operation of a pilot-scale anaerobic membrane bioreactor for the treatment of real municipal wastewater. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 813:152643. [PMID: 34963601 DOI: 10.1016/j.scitotenv.2021.152643] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 12/16/2021] [Accepted: 12/19/2021] [Indexed: 06/14/2023]
Abstract
The anaerobic membrane bioreactor (AnMBR) is a promising sustainable process and technology for the treatment of municipal wastewater from the perspective of carbon neutrality. In this study, a large pilot-scale AnMBR was constructed and the microbial community development of the anaerobic digested sludge in the AnMBR was determined during the treatment of municipal wastewater. The AnMBR system was conducted for 217 days during a long-term operation with the feed of real municipal wastewater. The characterization and dynamics of the microorganisms revealed that a stable prokaryotic community was gradually achieved. In the community of methane-producing archaea (or methanogens), the acetotrophic methanogen Methanosaeta was significantly enriched at an ambient temperature of 25 °C with an overwhelming relative abundance in the entire community. The abundance of Methanosaeta was even higher than the most abundant bacterial phyla Chloroflexi, Firmicutes, Proteobacteria and Bacteroidetes. This phenomenon is quite different from that found in other typical anaerobic systems. The massive enrichment of methanogens is the key to maintaining stable methane production in the treatment of municipal wastewater by the AnMBR. The interspecies cooperation of major functional bacterial groups including protein/carbohydrate/cellulose-degrading (genera Anaerovorax, Aminomonas, Levilinea, Flexilinea and Ruminococcus etc.), sulfate-reducing (Desulfovibrio and Desulfomicrobium etc.) and syntrophic (Syntrophorhabdus and Syntrophus etc.) bacteria with acetotrophic and hydrogenotrophic archaea enhances the stability of reactor operation and help to acclimate the entire prokaryotic community to the characteristics of real municipal wastewater.
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Affiliation(s)
- Zhe Kong
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China; National and Local Joint Engineering Laboratory of Municipal Sewage Resource Utilization Technology, Suzhou University of Science and Technology, Suzhou 215009, China; Jiangsu Collaborative Innovation Center of Water Treatment Technology and Material, Suzhou University of Science and Technology, Suzhou 215009, China; Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, Aoba Ward, Sendai, Miyagi 980-8579, Japan.
| | - Lu Li
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China; Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, Aoba Ward, Sendai, Miyagi 980-8579, Japan
| | - Jiang Wu
- Center for Material Cycles and Waste Management Research, National Institute for Environmental Studies, Tsukuba 305-8506, Japan
| | - Chao Rong
- Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, Aoba Ward, Sendai, Miyagi 980-8579, Japan
| | - Tianjie Wang
- Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, Aoba Ward, Sendai, Miyagi 980-8579, Japan
| | - Rong Chen
- International S&T Cooperation Center for Urban Alternative Water Resources Development, Key Lab of Environmental Engineering, Shaanxi Province, Xi'an University of Architecture and Technology, No. 13 Yanta Road, Xi'an 710055, PR China
| | - Daisuke Sano
- Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, Aoba Ward, Sendai, Miyagi 980-8579, Japan
| | - Yu-You Li
- Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, Aoba Ward, Sendai, Miyagi 980-8579, Japan.
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Wang J, Li M, Guan A, Liu R, Qi W, Liu H, Qu J. Can radicals-orientated chemical oxidation improve the reduction of antibiotic resistance genes (ARGs) by mesophilic anaerobic digestion of sludge? JOURNAL OF HAZARDOUS MATERIALS 2022; 426:128001. [PMID: 34933261 DOI: 10.1016/j.jhazmat.2021.128001] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 11/19/2021] [Accepted: 12/04/2021] [Indexed: 06/14/2023]
Abstract
The dissemination of antibiotic resistance genes (ARGs) increases risks towards human health and environmental safety. This work investigates the control of ARGs abundance and bacterial community evolution involved in waste activated sludge (WAS) treatment by chemical conditioning and subsequent mesophilic anaerobic digestion (MAD). The different chemical oxidation processes of ferrous iron-activated oxone and hydrogen peroxide (PMS-Fe2+ and H2O2-Fe2+) and thermal-activated oxone (PMS@80 ℃) were investigated, and the ferric chloride (FeCl3) and inactivated oxone (PMS) were compared. PMS@80 ℃ decreased the absolute abundance of most ARGs by 10.6-99.3% and that of total ARGs by 66.3%. Interestingly, oxidation pretreatment increased rather than decreased the relative abundance of most ARGs. MAD with PMS@80 ℃ pretreatment increased the absolute abundance of total ARGs by 51.6%, and other MAD processes decreased it by 8.6-47.4%. PMS-Fe2+ and PMS@80 ℃ negatively inhibited methane production from 98.3 to 81.7 and 94.4 mL/g VSS in MAD. MAD effluent showed high abundance of Arcobacter genus in the range of 8.1-17.4% upon PMS-based pretreatment, possibly related to sulfur oxidation, nitrate reduction, and blaVEB enrichment. The radicals-orientated chemical oxidation can hardly improve the ARGs elimination by MAD due to the extremely high competitive organics in sludge.
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Affiliation(s)
- Jiaqi Wang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Mengtian Li
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Aomei Guan
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ruiping Liu
- Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Weixiao Qi
- Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
| | - Huijuan Liu
- Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Jiuhui Qu
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China; Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
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12
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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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13
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Zhang Q, Zeng L, Fu X, Pan F, Shi X, Wang T. Comparison of anaerobic co-digestion of pig manure and sludge at different mixing ratios at thermophilic and mesophilic temperatures. BIORESOURCE TECHNOLOGY 2021; 337:125425. [PMID: 34157435 DOI: 10.1016/j.biortech.2021.125425] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 06/12/2021] [Accepted: 06/14/2021] [Indexed: 06/13/2023]
Abstract
The objective of this study is to assess the effects of the mixing ratio on the methane production and digestate dewaterability of co-digestion of pig manure (P) and sludge (S). Batch experiments were carried out at five different P/S mixing ratios at mesophilic and thermophilic temperatures. Compared to sludge anaerobic digestion, co-digestion of pig manure with sludge increased methane yield 83.0%-136.5% at mesophilic temperature and 31.3%-68.0% at thermophilic temperature. The normalized capillary suction time (NCST) and total solids (TS) of sediment (centrifugal dewatering) increased when pig manure proportion of substrate increased. The NCST at thermophilic temperatures (4.87-17.58 s g-1-TSS) was higher than that at mesophilic temperatures (1.89-10.95 s g-1-TSS). However, the TS of sediment was close at thermophilic and mesophilic temperatures. The results indicated that anaerobic co-digestion of pig manure and sludge at a proper mixing ratio (P/S = 2:1) provides a good choice for energy recovery and land utilization.
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Affiliation(s)
- Qingfang Zhang
- College of Petrochemical Engineering, Lanzhou University of Technology, Lanzhou 730050, China
| | - Liyuan Zeng
- College of Petrochemical Engineering, Lanzhou University of Technology, Lanzhou 730050, China
| | - Xin Fu
- Jiangxi Province Engineering Research Center of Ecological Chemical Industry (Jiujiang University), Jiujiang 332005, China
| | - Feng Pan
- Jiangxi Province Engineering Research Center of Ecological Chemical Industry (Jiujiang University), Jiujiang 332005, China
| | - Xiaofeng Shi
- Xi'an Scientific Research Institute of Environmental Protection, Xi'an 710061, China
| | - Tianfeng Wang
- College of Petrochemical Engineering, Lanzhou University of Technology, Lanzhou 730050, China; Jiangxi Province Engineering Research Center of Ecological Chemical Industry (Jiujiang University), Jiujiang 332005, China.
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14
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Shahzad HMA, Khan SJ, Zeshan, Jamal Y, Habib Z. Evaluating the performance of anaerobic moving bed bioreactor and upflow anaerobic hybrid reactor for treating textile desizing wastewater. Biochem Eng J 2021. [DOI: 10.1016/j.bej.2021.108123] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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15
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Jang J, Abbas A, Kim M, Shin J, Kim YM, Cho KH. Prediction of antibiotic-resistance genes occurrence at a recreational beach with deep learning models. WATER RESEARCH 2021; 196:117001. [PMID: 33744657 DOI: 10.1016/j.watres.2021.117001] [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: 11/06/2020] [Revised: 02/27/2021] [Accepted: 03/01/2021] [Indexed: 06/12/2023]
Abstract
Antibiotic resistance genes (ARGs) have been reported to threaten the public health of beachgoers worldwide. Although ARG monitoring and beach guidelines are necessary, substantial efforts are required for ARG sampling and analysis. Accordingly, in this study, we predicted ARGs occurrence that are primarily found on the coast after rainfall using a conventional long short-term memory (LSTM), LSTM-convolutional neural network (CNN) hybrid model, and input attention (IA)-LSTM. To develop the models, 10 categories of environmental data collected at 30-min intervals and concentration data of 4 types of major ARGs (i.e., aac(6'-Ib-cr), blaTEM, sul1, and tetX) obtained at the Gwangalli Beach in South Korea, between 2018 and 2019 were used. When individually predicting ARGs occurrence, the conventional LSTM and IA-LSTM exhibited poor R2 values during training and testing. In contrast, the LSTM-CNN exhibited a 2-6-times improvement in accuracy over those of the conventional LSTM and IA-LSTM. However, when predicting all ARGs occurrence simultaneously, the IA-LSTM model exhibited a superior performance overall compared to that of LSTM-CNN. Additionally, the influence of environmental variables on prediction was investigated using the IA-LSTM model, and the ranges of input variables that affect each ARG were identified. Consequently, this study demonstrated the possibility of predicting the occurrence and distribution of major ARGs at the beach based on various environmental variables, and the results are expected to contribute to management of ARG occurrence at a recreational beach.
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Affiliation(s)
- Jiyi Jang
- Department of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), 50, UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan, 44919 South Korea
| | - Ather Abbas
- Department of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), 50, UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan, 44919 South Korea
| | - Minjeong Kim
- Division of Radioactive Waste Disposal Research, Korea Atomic Energy Research Institute (KAERI), 989-111, Daedeok-daero, Yuseong-gu, Daejeon, 34057, South Korea
| | - Jingyeong Shin
- Department of Civil and Environmental Engineering, Hanyang University, 222, Wangsimni-ro, Seongdong-gu, Seoul, 04763, South Korea
| | - Young Mo Kim
- Department of Civil and Environmental Engineering, Hanyang University, 222, Wangsimni-ro, Seongdong-gu, Seoul, 04763, South Korea
| | - Kyung Hwa Cho
- Department of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), 50, UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan, 44919 South Korea.
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16
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Jang J, Kim M, Baek S, Shin J, Shin J, Shin SG, Kim YM, Cho KH. Hydrometeorological Influence on Antibiotic-Resistance Genes (ARGs) and Bacterial Community at a Recreational Beach in Korea. JOURNAL OF HAZARDOUS MATERIALS 2021; 403:123599. [PMID: 32791479 DOI: 10.1016/j.jhazmat.2020.123599] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Revised: 06/29/2020] [Accepted: 07/27/2020] [Indexed: 06/11/2023]
Abstract
We investigated the occurrence and distribution of antibiotic-resistance genes (ARGs) and the composition of a bacterial community under conditions of rainfall on a recreational beach in Korea. Seawater samples, collected every 1‒5 hours in June 2018 and May 2019, were analyzed using quantitative real-time polymerase chain reaction and next-generation sequencing. We found a substantial influence of rainfall and tidal levels on the relative abundance of total ARGs and bacterial operational taxonomic units (OTUs), which showed 1.9 × 103 and 1.1 × 101 fold increases, respectively. In particular, the elevated levels of ARGs were maintained for up to 32 hours after rainfall. An increased abundance of sewage-related ARGs and bacterial OTUs suggested that combined sewer overflow (CSO) may be the major factor contributing to the increase in the number and diversity of ARGs and related bacterial communities. Network analysis of ARGs and OTUs indicated that, at the genus level, Acinetobacter, Pseudomonas, and Prevotella were the main potential pathogens carrying the observed ARGs in the recreational seawater. Overall, these findings highlight the potential threat to public health on beaches, and indicate the requirement for more adequate monitoring, with greater efforts to mitigate the propagation of ARGs arising from CSOs.
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Affiliation(s)
- Jiyi Jang
- School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology, 50, UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan, 44919, Republic of Korea
| | - Minjeong Kim
- Korea Atomic Energy Research Institute, 111, Daedeok-daero 989beon-gil, Yuseong-gu, Daejeon, 34057, Republic of Korea
| | - Sangsoo Baek
- School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology, 50, UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan, 44919, Republic of Korea
| | - Jingyeong Shin
- Department of Civil and Environmental Engineering, Hanyang University, 222, Wangsimni-ro, Seongdong-gu, Seoul, 04763, Republic of Korea
| | - Juhee Shin
- Department of Energy Engineering, Future Convergence Technology Research Institute, Gyeongnam National University of Science and Technology, 6, Naedong-ro 139beon-gil, Naedong-myeon, Jinju, 52725, Republic of Korea
| | - Seung Gu Shin
- Department of Energy Engineering, Future Convergence Technology Research Institute, Gyeongnam National University of Science and Technology, 6, Naedong-ro 139beon-gil, Naedong-myeon, Jinju, 52725, Republic of Korea
| | - Young Mo Kim
- Department of Civil and Environmental Engineering, Hanyang University, 222, Wangsimni-ro, Seongdong-gu, Seoul, 04763, Republic of Korea
| | - Kyung Hwa Cho
- School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology, 50, UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan, 44919, Republic of Korea.
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17
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Genome-Centric Metagenomic Insights into the Impact of Alkaline/Acid and Thermal Sludge Pretreatment on the Microbiome in Digestion Sludge. Appl Environ Microbiol 2020; 86:AEM.01920-20. [PMID: 32948522 DOI: 10.1128/aem.01920-20] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 09/15/2020] [Indexed: 01/12/2023] Open
Abstract
Pretreatment of waste-activated sludge (WAS) is an effective way to destabilize sludge floc structure and release organic matter for improving sludge digestion efficiency. Nonetheless, information on the impact of WAS pretreatment on digestion sludge microbiomes, as well as mechanistic insights into how sludge pretreatment improves digestion performance, remains elusive. In this study, a genome-centric metagenomic approach was employed to investigate the digestion sludge microbiome in four sludge digesters with different types of feeding sludge: WAS pretreated with 0.25 mol/liter alkaline/acid (APAD), WAS pretreated with 0.8 mol/liter alkaline/acid (HS-APAD), thermally pretreated WAS (thermal-AD), and fresh WAS (control-AD). We retrieved 254 metagenome-assembled genomes (MAGs) to identify the key functional populations involved in the methanogenic digestion process. These MAGs span 28 phyla, including 69 yet-to-be-cultivated lineages, and 30 novel lineages were characterized with metabolic potential associated with hydrolysis and fermentation. Interestingly, functional populations involving carbohydrate digestion were enriched in APAD and HS-APAD, while lineages related to protein and lipid fermentation were enriched in thermal-AD, corroborating the idea that different substrates are released from alkaline/acid and thermal pretreatments. Among the major functional populations (i.e., fermenters, syntrophic acetogens, and methanogens), significant correlations between genome sizes and abundance of the fermenters were observed, particularly in APAD and HS-APAD, which had improved digestion performance.IMPORTANCE Wastewater treatment generates large amounts of waste-activated sludge (WAS), which consists mainly of recalcitrant microbial cells and particulate organic matter. Though WAS pretreatment is an effective way to release sludge organic matter for subsequent digestion, detailed information on the impact of the sludge pretreatment on the digestion sludge microbiome remains scarce. Our study provides unprecedented genome-centric metagenomic insights into how WAS pretreatments change the digestion sludge microbiomes, as well as their metabolic networks. Moreover, digestion sludge microbiomes could be a unique source for exploring microbial dark matter. These results may inform future optimization of methanogenic sludge digestion and resource recovery.
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18
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Lim EY, Tian H, Chen Y, Ni K, Zhang J, Tong YW. Methanogenic pathway and microbial succession during start-up and stabilization of thermophilic food waste anaerobic digestion with biochar. BIORESOURCE TECHNOLOGY 2020; 314:123751. [PMID: 32619808 DOI: 10.1016/j.biortech.2020.123751] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 06/24/2020] [Accepted: 06/25/2020] [Indexed: 05/22/2023]
Abstract
One of the major obstacles for thermophilic anaerobic digestion is the process instability during start-up. This study proposed the use of a cost-effective additive, biochar, to accelerate and stabilize the start-up of thermophilic semi-continuous food waste anaerobic digestion. The results showed that the reactors with biochar addition resulted in up to 18% higher methane yield as compared to the control reactors (without biochar). The key microbial networks were elucidated through thermochemical and microbial analysis. Particularly, the addition of biochar promoted the growth of electroactive Clostridia and other electroactive bacteria, while the absence of biochar promoted the growth of homoacetogenic Clostridia and syntrophic acetate oxidizing bacteria. It was revealed that biochar promoted direct interspecies electron transfer between the microbes and was responsible for the faster degradation of volatile fatty acids. Furthermore, reactors with biochar also enhanced the thermodynamically favourable acetoclastic methanogenic pathway due to the higher abundance of Methanosarcina.
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Affiliation(s)
- Ee Yang Lim
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, S117576 Singapore, Singapore
| | - Hailin Tian
- NUS Environment Research Institute, National University of Singapore, 5A Engineering Drive 1, Singapore 117411, Singapore
| | - Yangyang Chen
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Canada
| | - Kewei Ni
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Canada
| | - Jingxin Zhang
- China-UK Low Carbon College, Shanghai Jiao Tong University, Shanghai 201306, China
| | - Yen Wah Tong
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, S117576 Singapore, Singapore; NUS Environment Research Institute, National University of Singapore, 5A Engineering Drive 1, Singapore 117411, Singapore.
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19
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Jeon D, Chung K, Shin J, Min Park C, Gu Shin S, Mo Kim Y. Reducing food waste in residential complexes using a pilot-scale on-site system. BIORESOURCE TECHNOLOGY 2020; 311:123497. [PMID: 32408195 DOI: 10.1016/j.biortech.2020.123497] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 05/03/2020] [Accepted: 05/05/2020] [Indexed: 06/11/2023]
Abstract
A pilot-scale on-site system combining biological treatment and a drying stage was applied to achieve mass reduction of food waste (FW) at an urban residential complex. The effectiveness of biodegrading the organic portion of FW via microorganisms existing in FW improved by 38.80% by controlling rates of FW loading and air-flow. In one stage of the on-site biological treatment, the major bacterial community was identified to be mesophilic and facultative; Lactobacillus was the most dominant genus, accounting for 78.1% of bacterial community. Total mass reduction of FW approached 90.15% by increasing removal of both moisture and the organic portion of FW. In addition, the solids and liquids of the final by-products have the potential to be recycled into resources such as fertilizer, a bio-solid refuse fuel or external carbon sources for wastewater treatment plants. The proposed decentralized system offers practical and environmental approaches for FW management in residential complexes.
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Affiliation(s)
- Dawoon Jeon
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology, Buk-gu, Gwangju 500-712, Republic of Korea
| | - Kyungmi Chung
- GS E&C Research Institute, Building & Environment Research Team, 388,Baeok-daero Idong-myeon, Cheoin-gu, Yongin-si, Gyeonggi-do, Republic of Korea
| | - Jingyeong Shin
- Department of Civil and Environmental Engineering, Hanyang University, Seongdong-gu, Seoul 04763, Republic of Korea
| | - Chang Min Park
- Department of Environmental Engineering, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea
| | - Seung Gu Shin
- Department of Energy Engineering, Future Convergence Technology Research Institute, Gyeongnam National University of Science and Technology, Jinju 52725, Republic of Korea
| | - Young Mo Kim
- Department of Civil and Environmental Engineering, Hanyang University, Seongdong-gu, Seoul 04763, Republic of Korea.
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20
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Shin J, Rhee C, Shin J, Min Jang H, Gu Shin S, Mo Kim Y. Determining the composition of bacterial community and relative abundance of specific antibiotics resistance genes via thermophilic anaerobic digestion of sewage sludge. BIORESOURCE TECHNOLOGY 2020; 311:123510. [PMID: 32446235 DOI: 10.1016/j.biortech.2020.123510] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 05/03/2020] [Accepted: 05/05/2020] [Indexed: 06/11/2023]
Abstract
In this study, the effects of different temperature transitions on the dynamics of antibiotic resistance genes (ARGs) and bacterial community were investigated during start-up of thermophilic anaerobic digestion (AD) of sewage sludge. Although two thermophilic reactors showed dissimilar removal efficiencies of ARGs in batch mode, both the removal efficiency and reduction patterns of ARGs were similar in continuous stirred tank reactor (CSTR) mode, resulting in significant reduction of the total sum of the relative abundance of ARGs. Using network analysis to explore the correlation between bacterial community and some specific ARGs revealed that composition of the bacterial community played a vital role in the fluctuations in the relative abundance of the antibiotic resistome, demonstrating that shaping the development of ARGs was facilitated by vertical gene transfer. To facilitate eliminating ARGs, minimizing their hosts which persist even under long-term operations is vital in thermophilic AD.
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Affiliation(s)
- Jingyeong Shin
- Department of Civil and Environmental Engineering, Hanyang University, Seongdong-gu, Seoul 04763, Republic of Korea
| | - Chaeyoung Rhee
- Department of Energy Engineering, Future Convergence Technology Research Institute, Gyeongnam National University of Science and Technology, 6 Naedong-ro 139beon-gil, Jinju 52725, Republic of Korea
| | - Juhee Shin
- Department of Energy Engineering, Future Convergence Technology Research Institute, Gyeongnam National University of Science and Technology, 6 Naedong-ro 139beon-gil, Jinju 52725, Republic of Korea
| | - Hyun Min Jang
- Engineering and Soil Environment Research Center, Jeonbuk National University, Jeonju, Jeollabukdo 54896, Republic of Korea
| | - Seung Gu Shin
- Department of Energy Engineering, Future Convergence Technology Research Institute, Gyeongnam National University of Science and Technology, 6 Naedong-ro 139beon-gil, Jinju 52725, Republic of Korea
| | - Young Mo Kim
- Department of Civil and Environmental Engineering, Hanyang University, Seongdong-gu, Seoul 04763, Republic of Korea.
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21
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Zhang J, Qi Q, Mao L, He Y, Loh KC, Wah Tong Y. Mixing strategies - Activated carbon nexus: Rapid start-up of thermophilic anaerobic digestion with the mesophilic anaerobic sludge as inoculum. BIORESOURCE TECHNOLOGY 2020; 310:123401. [PMID: 32334361 DOI: 10.1016/j.biortech.2020.123401] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 04/13/2020] [Accepted: 04/16/2020] [Indexed: 06/11/2023]
Abstract
This study evaluated the mixing - activate carbon nexus in anaerobic digestion with the aim of accelerating start-up of thermophilic anaerobic co-digestion of food waste and chicken manure using mesophilic anaerobic sludge as inoculum. Results showed that the methane yield in the continuous stirred reactor is 71.3% higher than that of intermittent agitated reactor, and the addition of activated carbon can further improve the yield of methane by 18.2%. Continuous mixing mode followed by intermittent mixing was proved to be an alternative strategy to accelerate start-up of thermophilic anaerobic digestion. The optimum mixing time of 120 s/hour were obtained using computational fluid dynamics modeling. Analysis of genomic annotation metabolism indicated that the addition of activated carbon enhanced the dominant metabolism pathways of amino acid, methane and energy. Results of enzymes gene expression suggested that carbohydrates esterases, glycoside hydrolases and glycosyl transferases were dominant, respectively.
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Affiliation(s)
- Jingxin Zhang
- China-UK Low Carbon College, Shanghai Jiao Tong University, Shanghai 201306, China.
| | - Qiuxian Qi
- China-UK Low Carbon College, Shanghai Jiao Tong University, Shanghai 201306, China
| | - Liwei Mao
- Environmental Research Institute, National University of Singapore, Singapore
| | - Yiliang He
- China-UK Low Carbon College, Shanghai Jiao Tong University, Shanghai 201306, China; School of Environmental Science and Engineering, Shanghai Jiao Tong University, China
| | - Kai-Chee Loh
- Department of Chemical & Biomolecular Engineering, National University of Singapore, Singapore
| | - Yen Wah Tong
- Environmental Research Institute, National University of Singapore, Singapore; Department of Chemical & Biomolecular Engineering, National University of Singapore, Singapore
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22
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Thermophilic Methane Production from Hydrothermally Pretreated Norway Spruce (Picea abies). APPLIED SCIENCES-BASEL 2020. [DOI: 10.3390/app10144989] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Norway spruce (Picea abies) is an industrially important softwood species available in northern Europe and can be used to produce bio-methane after proper pretreatment to overcome its recalcitrant complex structure. Hot water extraction (HWE) pretreatment at two different conditions (170 °C for 90 min (severity 4.02) and 140 °C for 300 min (severity 3.65)) was applied to extract hemicellulosic sugars from Norway spruce for thermophilic anaerobic digestion (AD) of the hydrolysate. The methane yield of hydrolysate prepared at the lower pretreatment severity was found to be 189 NmL/gCOD compared to 162 NmL/gCOD after the higher pretreatment severity suggesting higher pretreatment severity hampers the methane yield due to the presence of inhibitors formed due to sugars and lignin degradation and soluble lignin, extracted partially along with hemicellulosic sugars. Synthetic hydrolysates simulating real hydrolysates (H170syn and H140syn) had improved methane yield of 285 NmL/gCOD and 295 NmL/gCOD, respectively in the absence of both the inhibitors and soluble lignin. An effect of organic loadings (OLs) on the methane yield was observed with a negative correlation between OL and methane yield. The maximum methane yield was 290 NmL/gCOD for hydrolysate pretreated at 140 °C compared to 195 NmL/gCOD for hydrolyate pretreated at 170 °C, both at the lowest OL of 6 gCOD/L. Therefore, both pretreatment conditions and OL need to be considered for efficient methane production from extracted hydrolysate. Such substrates can be utilized in continuous flow industrial AD with well-adapted cultures with stable organic loading rates.
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Chen Z, Li W, Qin W, Sun C, Wang J, Wen X. Long-term performance and microbial community characteristics of pilot-scale anaerobic reactors for thermal hydrolyzed sludge digestion under mesophilic and thermophilic conditions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 720:137566. [PMID: 32146395 DOI: 10.1016/j.scitotenv.2020.137566] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 02/22/2020] [Accepted: 02/24/2020] [Indexed: 06/10/2023]
Abstract
Anaerobic digestion (AD) with thermal hydrolysis pretreatment has been attracted widespread attention in recent years due to its high efficiency. However, few studies focus on systematical comparison of the downstream AD processes for thermal hydrolyzed sludge and their corresponding microbial community compositions, especially on those at pilot scale and above. Thus, this study systematically compared the long-term performance and microbial communities of two pilot-scale anaerobic reactors for thermal hydrolyzed sludge digestion under mesophilic and thermophilic conditions. The results presented that mesophilic anaerobic digestion (MAD) showed a better performance of methane production than thermophilic anaerobic digestion (TAD). The hydraulic retention time (HRT) needed to be longer than 12 days in MAD while 20 days in TAD to achieve the relatively high methane production, which could be explained by that the ammonia nitrogen accumulation especially the free ammonia determined in TAD was higher than that in MAD at all HRTs, emerging an inhibition of methane yield in TAD. High-throughput Illumina sequencing results demonstrated a more diverse microbial community in MAD than that in TAD. TAD was mediated by a suite of thermophiles, such as Coprothermobacter and Methanothermobacter, while taxa harbored in MAD mostly belonged to Bacteroidetes and relatively broad types of methanogens. In addition, hydrogenotrophic methanogens were the predominant of archaea communities in both digesters probably due to the relatively high concentration of ammonia nitrogen.
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Affiliation(s)
- Zhan Chen
- School of Environment, Tsinghua University, Beijing 10084, China
| | - Wei Li
- Research and Development Center, Beijing Drainage Group Co. Ltd., Beijing 100124, China
| | - Wentao Qin
- School of Environment, Tsinghua University, Beijing 10084, China; Institute of Plant and Environment Protection, Beijing Academy of Agriculture and Forestry Sciences, Beijing Engineering Research Center for Edible Mushroom, Beijing 100097, China
| | - Chenxiang Sun
- School of Environment, Tsinghua University, Beijing 10084, China
| | - Jiawei Wang
- Research and Development Center, Beijing Drainage Group Co. Ltd., Beijing 100124, China
| | - Xianghua Wen
- School of Environment, Tsinghua University, Beijing 10084, China.
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