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Perman E, Karlsson A, Westerholm M, Isaksson S, Schnürer A. High-solid digestion - A comparison of completely stirred and plug-flow reactor systems. WASTE MANAGEMENT (NEW YORK, N.Y.) 2024; 189:265-275. [PMID: 39217801 DOI: 10.1016/j.wasman.2024.08.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2024] [Revised: 08/17/2024] [Accepted: 08/21/2024] [Indexed: 09/04/2024]
Abstract
High-solid digestion (HSD) for biogas production is a resource-efficient and sustainable method to treat organic wastes with high total solids content and obtain renewable energy and an organic fertiliser, using a lower dilution rate than in the more common wet digestion process. This study examined the effect of reactor type on the performance of an HSD process, comparing plug-flow (PFR) type reactors developed for continuous HSD processes, and completely stirred-tank reactors (CSTRs) commonly used for wet digestion. The HSD process was operated in thermophilic conditions (52 °C), with a mixture of household waste, garden waste and agricultural residues (total solids content 27-28 %). The PFRs showed slightly better performance, with higher specific methane production and nitrogen mineralisation than the CSTRs, while the reduction of volatile solids was the same in both reactor types. Results from 16S rRNA gene sequencing showed a significant difference in the microbial population, potentially related to large differences in stirring speed between the reactor types (1 rpm in PFRs and 70-150 rpm in CSTRs, respectively). The bacterial community was dominated by the genus Defluviitoga in the PFRs and order MBA03 in the CSTRs. For the archaeal community, there was a predominance of the genus Methanoculleus in the PFRs, and of the genera Methanosarcina and Methanothermobacter in the CSTRs. Despite these shifts in microbiology, the results showed that stable digestion of substrates with high total solids content can be achieved in both reactor types, indicating flexibility in the choice of technique for HSD processes.
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Affiliation(s)
- Ebba Perman
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden; Biogas Solutions Research Center, Linköping, Sweden
| | - Anna Karlsson
- Biogas Solutions Research Center, Linköping, Sweden; Biokraft International AB, Kungsbron 1, 111 22 Stockholm, Sweden
| | - Maria Westerholm
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden; Biogas Solutions Research Center, Linköping, Sweden
| | - Simon Isaksson
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Anna Schnürer
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden; Biogas Solutions Research Center, Linköping, Sweden.
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2
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Naidu GM, Raturi A, Mani FS. Anaerobic digestion of poultry manure to power a poultry farm in Ba: Pilot and techno-economic study. Heliyon 2024; 10:e36325. [PMID: 39263091 PMCID: PMC11387272 DOI: 10.1016/j.heliyon.2024.e36325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2024] [Revised: 07/25/2024] [Accepted: 08/13/2024] [Indexed: 09/13/2024] Open
Abstract
Although poultry is the largest meat by volume produced in Fiji, there has not been any established study, nor application of the anaerobic digestion (AD) of poultry manure (PM) in the country. This paper aims to determine the techno-economic feasibility of the AD of PM to power a poultry farm in Fiji. A pilot scale study was first conducted with mono-digestion batches of poultry manure, and co-digestions with kitchen waste (KW) and newspaper waste (NPW). Solid state anaerobic digestion (SSAD) was employed in all the batches, and the key operational parameters of AD were studied, along with its influence on biogas production. The pilot study revealed that even slight changes in environmental temperature had the greatest effect on biogas production. The most resilient to the temperature changes were the co-digested feedstocks of KW. Yet, given a substantial AD period, the anaerobes in the mono-digesters were able to eventually acclimatize to the SSAD environment, and produce the overall highest biogas production. The pilot study results were then used to conduct a feasibility study of the full-scale design. The analysis showed that the SSAD system would generate 189.46 MWh of electricity annually, with a levelized cost of energy of FJ$0.17/KWh.
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Affiliation(s)
- Geeta M Naidu
- Master of Science Programme, School of Information Technology, Engineering, Mathematics and Physics, University of the South Pacific, Suva, Fiji
| | - Atul Raturi
- School of Information Technology, Engineering, Mathematics and Physics, University of the South Pacific, Suva, Fiji
| | - Francis S Mani
- School of Agriculture, Geography, Environment, Ocean and Natural Sciences, University of the South Pacific, Suva, Fiji
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3
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Winkler J, Neuner T, Hupfauf S, Arthofer A, Ebner C, Rauch W, Bockreis A. Impact of impeller design on anaerobic digestion: Assessment of mixing dynamics, methane yield, microbial communities and digestate dewaterability. BIORESOURCE TECHNOLOGY 2024; 406:131095. [PMID: 38986887 DOI: 10.1016/j.biortech.2024.131095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Revised: 06/26/2024] [Accepted: 07/06/2024] [Indexed: 07/12/2024]
Abstract
The efficiency of anaerobic digestion (AD) processes is intricately tied to mixing quality. This research investigates the influence of two impeller types, namely a helical ribbon impeller (HRI) and a pitched-blade impeller (PBI), on key aspects of AD. The investigation encompassed mixing dynamics, methane production, microbial communities, and the previously unexplored impact on digestate dewaterability. Results show that agitation with the PBI exhibited stratification, with bottom layer total solids (TS) values of 3.1% for the PBI and 2.6% for the HRI. Nevertheless, methane yield remained unchanged, averaging 286 LN/kg volatile solids (VS)added. Slower mixing with the HRI achieved more uniform mixing and reduced energy requirements. Additionally, impeller type significantly affected digestate dewaterability, leading to a 3.8% increase in TS of the dewatered sludge when using the PBI. These findings highlight the importance of considering mixing not only for methane production and reduced maintenance but also for achieving optimal digestate dewaterability.
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Affiliation(s)
- Jacqueline Winkler
- Department of Infrastructure, Universität Innsbruck, Technikerstraße 13, A-6020 Innsbruck, Austria.
| | - Thomas Neuner
- MCI, The Entrepreneurial School, Maximilianstraße 2, 6020 Innsbruck, Austria.
| | - Sebastian Hupfauf
- Department of Microbiology, Universität Innsbruck, Technikerstraße 25d, A-6020 Innsbruck, Austria.
| | - Anna Arthofer
- Department of Microbiology, Universität Innsbruck, Technikerstraße 25d, A-6020 Innsbruck, Austria.
| | - Christian Ebner
- Department of Infrastructure, Universität Innsbruck, Technikerstraße 13, A-6020 Innsbruck, Austria.
| | - Wolfgang Rauch
- Department of Infrastructure, Universität Innsbruck, Technikerstraße 13, A-6020 Innsbruck, Austria.
| | - Anke Bockreis
- Department of Infrastructure, Universität Innsbruck, Technikerstraße 13, A-6020 Innsbruck, Austria.
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Tomczak W, Gryta M, Daniluk M, Żak S. Biogas Upgrading Using a Single-Membrane System: A Review. MEMBRANES 2024; 14:80. [PMID: 38668108 PMCID: PMC11051867 DOI: 10.3390/membranes14040080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2024] [Revised: 03/22/2024] [Accepted: 03/25/2024] [Indexed: 04/28/2024]
Abstract
In recent years, the use of biogas as a natural gas substitute has gained great attention. Typically, in addition to methane (CH4), biogas contains carbon dioxide (CO2), as well as small amounts of impurities, e.g., hydrogen sulfide (H2S), nitrogen (N2), oxygen (O2) and volatile organic compounds (VOCs). One of the latest trends in biogas purification is the application of membrane processes. However, literature reports are ambiguous regarding the specific requirement for biogas pretreatment prior to its upgrading using membranes. Therefore, the main aim of the present study was to comprehensively examine and discuss the most recent achievements in the use of single-membrane separation units for biogas upgrading. Performing a literature review allowed to indicate that, in recent years, considerable progress has been made on the use of polymeric membranes for this purpose. For instance, it has been documented that the application of thin-film composite (TFC) membranes with a swollen polyamide (PA) layer ensures the successful upgrading of raw biogas and eliminates the need for its pretreatment. The importance of the performed literature review is the inference drawn that biogas enrichment performed in a single step allows to obtain upgraded biogas that could be employed for household uses. Nevertheless, this solution may not be sufficient for obtaining high-purity gas at high recovery efficiency. Hence, in order to obtain biogas that could be used for applications designed for natural gas, a membrane cascade may be required. Moreover, it has been documented that a significant number of experimental studies have been focused on the upgrading of synthetic biogas; meanwhile, the data on the raw biogas are very limited. In addition, it has been noted that, although ceramic membranes demonstrate several advantages, experimental studies on their applications in single-membrane systems have been neglected. Summarizing the literature data, it can be concluded that, in order to thoroughly evaluate the presented issue, the long-term experimental studies on the upgrading of raw biogas with the use of polymeric and ceramic membranes in pilot-scale systems are required. The presented literature review has practical implications as it would be beneficial in supporting the development of membrane processes used for biogas upgrading.
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Affiliation(s)
- Wirginia Tomczak
- Faculty of Chemical Technology and Engineering, Bydgoszcz University of Science and Technology, ul. Seminaryjna 3, 85-326 Bydgoszcz, Poland; (M.D.); (S.Ż.)
| | - Marek Gryta
- Faculty of Chemical Technology and Engineering, West Pomeranian University of Technology in Szczecin, ul. Pułaskiego 10, 70-322 Szczecin, Poland
| | - Monika Daniluk
- Faculty of Chemical Technology and Engineering, Bydgoszcz University of Science and Technology, ul. Seminaryjna 3, 85-326 Bydgoszcz, Poland; (M.D.); (S.Ż.)
| | - Sławomir Żak
- Faculty of Chemical Technology and Engineering, Bydgoszcz University of Science and Technology, ul. Seminaryjna 3, 85-326 Bydgoszcz, Poland; (M.D.); (S.Ż.)
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Adnane I, Taoumi H, Elouahabi K, Lahrech K, Oulmekki A. Valorization of crop residues and animal wastes: Anaerobic co-digestion technology. Heliyon 2024; 10:e26440. [PMID: 38439870 PMCID: PMC10909651 DOI: 10.1016/j.heliyon.2024.e26440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 02/08/2024] [Accepted: 02/13/2024] [Indexed: 03/06/2024] Open
Abstract
To switch the over-reliance on fossil-based resources, curb environmental quality deterioration, and promote the use of renewable fuels, much attention has recently been directed toward the implementation of sustainable and environmentally benign 'waste-to-energy' technology exploiting a clean, inexhaustible, carbon-neutral, and renewable energy source, namely agricultural biomass. From this perspective, anaerobic co-digestion (AcoD) technology emerges as a potent and plausible approach to attain sustainable energy development, foster environmental sustainability, and, most importantly, circumvent the key challenges associated with mono-digestion. This review article provides a comprehensive overview of AcoD as a biochemical valorization pathway of crop residues and livestock manure for biogas production. Furthermore, this manuscript aims to assess the different biotic and abiotic parameters affecting co-digestion efficiency and present recent advancements in pretreatment technologies designed to enhance feedstock biodegradability and conversion rate. It can be concluded that the substantial quantities of crop residues and animal waste generated annually from agricultural practices represent valuable bioenergy resources that can contribute to meeting global targets for affordable renewable energy. Nevertheless, extensive and multidisciplinary research is needed to evolve the industrial-scale implementation of AcoD technology of livestock waste and crop residues, particularly when a pretreatment phase is included, and bridge the gap between small-scale studies and real-world applications.
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Affiliation(s)
- Imane Adnane
- Sidi Mohamed Ben Abdellah University (USMBA), IPI Laboratory, ENS, Fez, Morocco
| | - Hamza Taoumi
- Sidi Mohamed Ben Abdellah University (USMBA), IPI Laboratory, ENS, Fez, Morocco
| | - Karim Elouahabi
- Sidi Mohamed Ben Abdellah University (USMBA), IPI Laboratory, ENS, Fez, Morocco
| | - Khadija Lahrech
- Sidi Mohamed Ben Abdellah University (USMBA), ENSA, Fez, Morocco
| | - Abdellah Oulmekki
- Laboratory of Processes, Materials and Environment (LPME), Faculty of Science and Technology, Sidi Mohamed Ben Abdellah University, Fez, Morocco
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Zhang L, Yuan Y, Zhang Y, Liu Y. Switching from wet to dry anaerobic digestion of food waste with different dilution times under no mechanical mixing condition. CHEMOSPHERE 2024; 352:141299. [PMID: 38296209 DOI: 10.1016/j.chemosphere.2024.141299] [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: 11/03/2023] [Revised: 01/19/2024] [Accepted: 01/23/2024] [Indexed: 02/10/2024]
Abstract
Previous research on anaerobic digestion of food waste has primarily focused on either wet or dry anaerobic digestion (AD), typically accompanied by continuous mechanical mixing. However, the necessary dilution rates and the extent of mixing required have yet to be addressed. In this study, we investigated switching from wet to dry AD of food waste without mechanical mixing, employing different dilution rates. Lab-scale anaerobic reactors were operated with dilution rates of 10, 5, and 2 times during Phases I (0-56 days), II (57-121 days), and III (122-209 days), respectively. The methane production rates were not significantly different (p > 0.05) across the dilution rates decreased from 10 to 2 times. Remarkably, the methane production in the anaerobic reactors exhibited fluctuations due to variations in feeding, with the methane production rate ranging from 2.0 to 2.7 g CH4-COD/(L d), without mechanical mixing, as the solids content transitioned from wet to near-dry digestion conditions (15 %, food waste). The distribution of sludge volatile solids concentrations remained uniform in the reactor, even at high solids concentrations of up to 15 %. A dynamic microbial community response to changes in dilution rates, with a shift from aceticlastic to hydrogenotrophic methanogenesis pathways. Syntrophic acetate oxidization bacteria (the genus Syner-01 (4.2-8.9 %) and f_Synergistaceae (3.6-4.2 %)) were highly enriched as switching from wet AD to dry AD. The study's findings provide crucial operational insights for anaerobic food waste treatment, potentially resulting in decreased water usage and operational costs, particularly in scenarios with low dilution rates and without mechanical mixing.
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Affiliation(s)
- Lei Zhang
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Canada; School of Civil & Environmental Engineering, Queensland University of Technology, Brisbane, QLD, Australia
| | - Yiyang Yuan
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Canada
| | - Yingdi Zhang
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Canada
| | - Yang Liu
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Canada; School of Civil & Environmental Engineering, Queensland University of Technology, Brisbane, QLD, Australia.
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7
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Liu Y, He P, Peng W, Zhang H, Lü F. Biochemical methane potential database: A public platform. BIORESOURCE TECHNOLOGY 2024; 393:130111. [PMID: 38013033 DOI: 10.1016/j.biortech.2023.130111] [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: 10/22/2023] [Revised: 11/24/2023] [Accepted: 11/24/2023] [Indexed: 11/29/2023]
Abstract
Diverse factors influence biogas production, such as material properties, testing conditions, reporting methods and other additional processing techniques. This complexity makes it difficult to compare biochemical methane potential (BMP) data, replicate experiments' results, and improve efficiencies associated with engineering applications. This study has taken preliminary attempts to build a sliced and structured BMP database, but optimizing the organization of data information and collecting more comprehensive and manually checked data information to cope with the increasing richness of the BMP test content. The first-generation BMP database contains 746 sets of data, covering 7 major substrate categories, including 187 key indicators and 26 supplementary indicators. It offers functions including data screening, comparing, uploading, and visual display of BMP data. The application of the database in comparing different types of substrates and additives is shown. In the future, the BMP database will be regularly upgraded to become more comprehensive.
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Affiliation(s)
- Yaheng Liu
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, People's Republic of China
| | - Pinjing He
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, People's Republic of China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, People's Republic of China; Jiaxing-Tongji Environmental Research Institute, Jiaxing 314051, Zhejiang Province, China
| | - Wei Peng
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, People's Republic of China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, People's Republic of China
| | - Hua Zhang
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, People's Republic of China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, People's Republic of China
| | - Fan Lü
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, People's Republic of China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, People's Republic of China; Jiaxing-Tongji Environmental Research Institute, Jiaxing 314051, Zhejiang Province, China.
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8
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Begum YA, Kumari S, Jain SK, Garg MC. A review on waste biomass-to-energy: integrated thermochemical and biochemical conversion for resource recovery. ENVIRONMENTAL SCIENCE: ADVANCES 2024. [DOI: 10.1039/d4va00109e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/20/2024]
Abstract
Integrating thermochemical–biochemical methods overcomes the single-path limits for bioenergy production. This synergy lowers costs and enhances energy sustainability, highlighting waste-to-energy's vital role in the circular economy transition.
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Affiliation(s)
- Yasmin Ara Begum
- Amity School of Engineering and Technology, Amity University Uttar Pradesh, Noida Sector-125, Uttar Pradesh 201313, India
| | - Sheetal Kumari
- Amity Institute of Environmental Sciences, Amity University Uttar Pradesh, Noida Sector-125, Uttar Pradesh 201313, India
| | - Shailendra Kumar Jain
- Amity School of Engineering and Technology, Amity University Uttar Pradesh, Noida Sector-125, Uttar Pradesh 201313, India
| | - Manoj Chandra Garg
- Amity Institute of Environmental Sciences, Amity University Uttar Pradesh, Noida Sector-125, Uttar Pradesh 201313, India
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Wang S, Li X, Dong R, Xiong W, Li Y, Zhu Y. Integration of in-situ and ex-situ power-to-gas (PtG) strategy for simultaneous bio-natural gas production and CO 2 emission reduction. CHEMOSPHERE 2023; 344:140370. [PMID: 37802480 DOI: 10.1016/j.chemosphere.2023.140370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 09/08/2023] [Accepted: 10/04/2023] [Indexed: 10/10/2023]
Abstract
A novel system integrating an in-situ and ex-situ power-to-gas (PtG) system was developed in the current study. A continuous stirred-tank reactor (CSTR) was operated using cattle manure as substrate at mesophilic temperature (37 °C ± 2 °C). The CH4 content in the biogas was upgraded to above 95% by H2 injection, which meets the highest criteria for grid injection without requiring CO2 removal. Furthermore, the bio-nature gas production was promoted by external CO2 and H2 injection. The volumetric methane production rate (VMPR) was significantly increased by 739% from 117.4 mL L-1·d-1 to 985 mL⋅L-1⋅d-1, which is higher than in other studies. Meanwhile, the volumetric biogas production rate (VBPR) was increased by 36.9% by H2 injection, increasing the conversion efficiency (82.56%) of the chemical oxygen demand (COD) to CH4. A significant increase in the specific methanogenic activity of dissolved hydrogen (SMA(Hdissolved)) and the enrichment in hydrogenotrophic methanogens (Methanobacterium) demonstrate that the CH4 production pathway was converted from acetoclastic methanogenesis (AM) pathway to hydrogenotrophic methanogenesis (HM) pathway. It is postulated that the change in proportion of different pathways of the CH4 production was caused by the strengthening of key enzymes (coenzyme F420 hydrogenase and coenzyme-B sulfoethylthiotransferase) by H2 injection. The integrated system represents a promising approach to achieve simultaneous CO2 emission reduction and bio-natural gas production.
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Affiliation(s)
- Siqi Wang
- College of Engineering, China Agricultural University (Key Laboratory for Clean Renewable Energy Utilization Technology, Ministry of Agriculture), Beijing, 100083, China
| | - Xin Li
- College of Engineering, China Agricultural University (Key Laboratory for Clean Renewable Energy Utilization Technology, Ministry of Agriculture), Beijing, 100083, China.
| | - Renjie Dong
- College of Engineering, China Agricultural University (Key Laboratory for Clean Renewable Energy Utilization Technology, Ministry of Agriculture), Beijing, 100083, China
| | - Wei Xiong
- Hubei Lvxin Ecological Technology Co., Ltd., (Xiangyang Key Laboratory of Agricultural Organic Waste Recycling), Yicheng, 441400, China
| | - Yu Li
- College of Engineering, China Agricultural University (Key Laboratory for Clean Renewable Energy Utilization Technology, Ministry of Agriculture), Beijing, 100083, China
| | - Yali Zhu
- College of Engineering, China Agricultural University (Key Laboratory for Clean Renewable Energy Utilization Technology, Ministry of Agriculture), Beijing, 100083, China
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10
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Machineni L, Anupoju GR. Optimization of biomethane production from sweet sorghum bagasse using artificial neural networks combined with particle swarm algorithm. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:114095-114110. [PMID: 37855961 DOI: 10.1007/s11356-023-30451-6] [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: 02/13/2023] [Accepted: 10/10/2023] [Indexed: 10/20/2023]
Abstract
In the face of international movement away from fossil fuels caused pollution menace, many research labs are rushing towards next big breakthrough via effective biorefinery development employing non-edible agro-residues as feedstock. This work aims to evaluate and optimize the methane potential of underutilized full strength sweet sorghum bagasse (SSB) via anaerobic digestion (AD). Biochemical methane potential assays are set up for SSB AD under mesophilic and thermophilic conditions at four substrate-o-inoculum ratios (SIR) 3, 5, 7, and 9 with pH 6.5, 7.5, and 8.5 and with 80, 90, and 100 rpm mixing speed over 50 days. SIR 5 produced the highest cumulative biomethane yield of 4.25 L methane g-1 VS with a shorter lag time of 7.5 days and technical digestion time of 24 days. The influence of physio-chemical parameters on AD process dynamics is supported with 16s rRNA metagenomic sequencing. Based on complete experimental data sets, two artificial neural network (ANN) models are developed to identify the relevant significance of process parameters and to predict bagasse methane potential. Further, the developed ANN model is integrated with particle swarm optimization algorithm to create ideal AD process operating conditions which maximize the target variable, biomethane. The trained and cross-validated ANN-PSO model showed good-fit-accuracy with R2 > 0.995 and demonstrated satisfactory performance in the biomethane yield prediction from AD of non-edible agri-residues.
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Affiliation(s)
- Lakshmi Machineni
- Bio Engineering and Environmental Sciences (BEES) Group, Department of Energy and Environmental Engineering (DEEE), CSIR-Indian Institute of Chemical Technology (IICT), Hyderabad, 500007, India.
| | - Gangagni Rao Anupoju
- Bio Engineering and Environmental Sciences (BEES) Group, Department of Energy and Environmental Engineering (DEEE), CSIR-Indian Institute of Chemical Technology (IICT), Hyderabad, 500007, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
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11
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Khan A, Pudhuvai B, Shrestha A, Mishra AK, Shah MP, Koul B, Dey N. CRISPR-mediated iron and folate biofortification in crops: advances and perspectives. Biotechnol Genet Eng Rev 2023:1-31. [PMID: 37092872 DOI: 10.1080/02648725.2023.2205202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
Abstract
Micronutrient deficiency conditions, such as anemia, are the most prevalent global health problem due to inadequate iron and folate in dietary sources. Biofortification advancements can propel the rapid amelioration of nutritionally beneficial components in crops that are required to combat the adverse effects of micronutrient deficiencies on human health. To date, several strategies have been proposed to increase micronutrients in plants to improve food quality, but very few approaches have intrigued `clustered regularly interspaced short palindromic repeats' (CRISPR) modules for the enhancement of iron and folate concentration in the edible parts of plants. In this review, we discuss two important approaches to simultaneously enhance the bioavailability of iron and folate concentrations in rice endosperms by utilizing advanced CRISPR-Cas9-based technology. This includes the 'tuning of cis-elements' and 'enhancer re-shuffling' in the regulatory components of genes that play a vital role in iron and folate biosynthesis/transportation pathways. In particular, base-editing and enhancer re-installation in native promoters of selected genes can lead to enhanced accumulation of iron and folate levels in the rice endosperm. The re-distribution of micronutrients in specific plant organs can be made possible using the above-mentioned contemporary approaches. Overall, the present review discusses the possible approaches for synchronized iron and folate biofortification through modification in regulatory gene circuits employing CRISPR-Cas9 technology.
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Affiliation(s)
- Ahamed Khan
- Biology Centre of the Czech Academy of Sciences, Institute of Plant Molecular Biology, České Budějovice, Czech Republic
| | - Baveesh Pudhuvai
- Department of Genetics and Biotechnology, Faculty of Agriculture and Technology, University of South Bohemia in České Budějovice, České Budějovice, Czech Republic
| | - Ankita Shrestha
- Division of Microbial and Plant Biotechnology, Department of Biotechnology, Government of India, Institute of Life Sciences, Bhubaneswar, Odisha, India
| | - Ajay Kumar Mishra
- Khalifa Centre for Genetic Engineering and Biotechnology, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Maulin P Shah
- Division of Applied and Environmental Microbiology, Enviro Technology Ltd, Ankleshwar, Gujarat, India
| | - Bhupendra Koul
- Department of Biotechnology, Lovely Professional University, Phagwara, Punjab, India
| | - Nrisingha Dey
- Division of Microbial and Plant Biotechnology, Department of Biotechnology, Government of India, Institute of Life Sciences, Bhubaneswar, Odisha, India
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12
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Tian M, Zhang R, Li J. Emergence of CRISPR/Cas9-mediated bioimaging: A new dawn of in-situ detection. Biosens Bioelectron 2023; 232:115302. [PMID: 37086563 DOI: 10.1016/j.bios.2023.115302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 04/03/2023] [Accepted: 04/05/2023] [Indexed: 04/24/2023]
Abstract
In-situ detection provides deep insights into the function of genes and their relationship with diseases by directly visualizing their spatiotemporal behavior. As an emerging in-situ imaging tool, clustered regularly interspaced short palindromic repeats (CRISPR)-mediated bioimaging can localize targets in living and fixed cells. CRISPR-mediated bioimaging has inherent advantages over the gold standard of fluorescent in-situ hybridization (FISH), including fast imaging, cost-effectiveness, and ease of preparation. Existing reviews have provided a detailed classification and overview of the principles of CRISPR-mediated bioimaging. However, the exploitation of potential clinical applicability of this bioimaging technique is still limited. Therefore, analyzing the potential value of CRISPR-mediated in-situ imaging is of great significance to the development of bioimaging. In this review, we initially discuss the available CRISPR-mediated imaging systems from the following aspects: summary of imaging substances, the design and optimization of bioimaging strategies, and factors influencing CRISPR-mediated in-situ detection. Subsequently, we highlight the potential of CRISPR-mediated bioimaging for application in biomedical research and clinical practice. Furthermore, we outline the current bottlenecks and future perspectives of CRISPR-based bioimaging. We believe that this review will facilitate the potential integration of bioimaging-related research with current clinical workflow.
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Affiliation(s)
- Meng Tian
- National Center for Clinical Laboratories, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/ National Center of Gerontology, People's Republic of China; Peking University Fifth School of Clinical Medicine, People's Republic of China; Beijing Engineering Research Center of Laboratory Medicine, Beijing Hospital, Beijing, People's Republic of China
| | - Rui Zhang
- National Center for Clinical Laboratories, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/ National Center of Gerontology, People's Republic of China; Peking University Fifth School of Clinical Medicine, People's Republic of China; Beijing Engineering Research Center of Laboratory Medicine, Beijing Hospital, Beijing, People's Republic of China.
| | - Jinming Li
- National Center for Clinical Laboratories, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing Hospital/ National Center of Gerontology, People's Republic of China; Peking University Fifth School of Clinical Medicine, People's Republic of China; Beijing Engineering Research Center of Laboratory Medicine, Beijing Hospital, Beijing, People's Republic of China.
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13
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Leca E, Zennaro B, Hamelin J, Carrère H, Sambusiti C. Use of additives to improve collective biogas plant performances: A comprehensive review. Biotechnol Adv 2023; 65:108129. [PMID: 36933869 DOI: 10.1016/j.biotechadv.2023.108129] [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: 12/08/2022] [Revised: 02/28/2023] [Accepted: 03/13/2023] [Indexed: 03/17/2023]
Abstract
Nowadays, anaerobic digestion (AD) is being increasingly encouraged to increase the production of biogas and thus of biomethane. Due to the high diversity among feedstocks used, the variability of operating parameters and the size of collective biogas plants, different incidents and limitations may occur (e.g., inhibitions, foaming, complex rheology). To improve performance and overcome these limitations, several additives can be used. This literature review aims to summarize the effects of the addition of various additives in co-digestion continuous or semi-continuous reactors to fit as much as possible with collective biogas plant challenges. The addition of (i) microbial strains or consortia, (ii) enzymes and (iii) inorganic additives (trace elements, carbon-based materials) in digester is analyzed and discussed. Several challenges associated with the use of additives for AD process at collective biogas plant scale requiring further research work are highlighted: elucidation of mechanisms, dosage and combination of additives, environmental assessment, economic feasibility, etc.
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Affiliation(s)
- Estelle Leca
- TotalEnergies, CSTJF, Centre Scientifique et Technique Jean Féger, Av. Larribau, 64000 Pau, France
| | - Bastien Zennaro
- INRAE Transfert, 60 Rue Nicolas Leblanc, 11100 Narbonne, France
| | - Jérôme Hamelin
- INRAE, Univ Montpellier, LBE, 102 Avenue des Etangs, 11100 Narbonne, France
| | - Hélène Carrère
- INRAE, Univ Montpellier, LBE, 102 Avenue des Etangs, 11100 Narbonne, France
| | - Cecilia Sambusiti
- TotalEnergies, CSTJF, Centre Scientifique et Technique Jean Féger, Av. Larribau, 64000 Pau, France.
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14
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Manyi-Loh CE, Okoh AI, Lues R. Occurrence and Multidrug Resistance in Strains of Listeria monocytogenes Recovered from the Anaerobic Co-Digestion Sludge Contained in a Single Stage Steel Biodigester: Implications for Antimicrobial Stewardship. Microorganisms 2023; 11:microorganisms11030725. [PMID: 36985298 PMCID: PMC10056191 DOI: 10.3390/microorganisms11030725] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 03/06/2023] [Accepted: 03/09/2023] [Indexed: 03/16/2023] Open
Abstract
L. monocytogenes is a zoonotic foodborne pathogen with inherent adaptability to tolerate environmental and physiological stresses, thereby causing severe disease outbreaks. Antibiotic resistant foodborne pathogens are a challenge to the food industry. A total of 18 samples were pooled from a bio-digester co-digesting swine manure/pinewood sawdust, and evaluated for the occurrence of bacterium plus total viable counts using the spread plate method. The recovered bacterial isolates were presumptively identified by growth on selective medium and confirmed by biochemical characterisation, leading to the isolation of 43 L. monocytogenes. The isolates were characterized based on their susceptibility to antibiotics via the Kirby-Bauer disc diffusion technique against a panel of 14 antibiotics. Equally, the multiple antibiotic resistance (MAR) index was calculated, and MAR phenotypes generated. The bacterial counts were between 102 and104 cfu/mL. Complete susceptibility (100%) was demonstrated to ampicillin, gentamicin and sulfamethoxazole, which are the drugs of choice in the treatment of listeriosis. In addition, intermediate sensitivity occurred at 25.58% to cefotaxime, and the highest resistance (51.16%) was exhibited against nalidixic acid. The MAR index ranged from 0 to 0.71. Overall, 41.86% of the Listeria isolates displayed multidrug resistance, with 18 different MAR phenotypes, demonstrating CIP, E, C, TET, AUG, S, CTX, NA, AML, NI as the greatest MAR phenotype. It can be concluded that the isolates yielding MAR > 0.2 originated from the farm, where antibiotics had been in routine use. Therefore, strict monitoring of antibiotics use in the farm is crucial to mitigate further increase in antibiotic resistance amongst these bacterial isolates.
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Affiliation(s)
- Christy Echakachi Manyi-Loh
- Centre of Applied Food Sustainability and Biotechnology (CAFSaB), Central University of Technology, Bloemfontein 9301, South Africa
- Correspondence: ; Tel.: +27-738324268
| | - Anthony Ifeanyin Okoh
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice 5700, South Africa;
- Department of Environmental Health Sciences, College of Health Sciences, University of Sharjah, Sharjah P.O. Box 26666, United Arab Emirates
| | - Ryk Lues
- Centre of Applied Food Sustainability and Biotechnology (CAFSaB), Central University of Technology, Bloemfontein 9301, South Africa
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15
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Khursheed A, Munshi FMA, Almohana AI, Alali AF, Kamal MA, Alam S, Alrehaili O, Islam DT, Kumar M, Varjani S, Kazmi AA, Tyagi VK. Resolution of conflict of reduced sludge production with EBPR by coupling OSA to A 2/O process in a pilot scale SBR. CHEMOSPHERE 2023; 318:137945. [PMID: 36702406 DOI: 10.1016/j.chemosphere.2023.137945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 12/26/2022] [Accepted: 01/22/2023] [Indexed: 06/18/2023]
Abstract
The pinnacle of all the efforts of nutrient removal is practically put-down the moment biological cells are lysed, hydrolyzed or digested causing subsequent reappearance of assimilated nitrogen and phosphorus in any biological process. While sludge reduction requires high SRT, the enhanced phosphorus assimilative uptake demands low SRT. A novel reactor configuration for enhanced sludge and phosphorus removal was put to test by incorporating a side stream anaerobic reactor to an Anaerobic-Anoxic-Aerobic (A2O) SBR with a pre-anoxic chamber and an influent receiving inlet anaerobic reactor. The reactor was operated at the average and lowest range of prevailing carbon/phosphorus (C/P) ratio of 50 and 15 in the sewage. The phosphorus enrichment was 0.0469-0.135 mgTP/mgVSS resulting in 1.76-5.05-fold increase from cellular content by virtue of maintaining sludge recycle from SBR aeration tank to side stream anaerobic reactor from 3.78 to 9.78 (average 4.4-8.2) gVSS/gVSS present in the reactor. However, the sludge was also reduced from 3% to 51% on an average basis during the same recirculation regime. This novel configuration consists of an inlet anaerobic reactor, one pre-anoxic chamber and one intermittent oxic anoxic reaction SBR and a side stream anaerobic reactor. The first anaerobic reactor at inlet followed by pre-anoxic chamber was provided for increased ortho-p released and nitrification respectively and a side stream anaerobic reactor for sludge reduction through sludge fasting mechanism. The EBPR and lesser sludge growth were two conflicting parameters reconciled to the extent that if sludge recycled up to 6.41 gVSS/gVSS the sludge growth would be reduced by 25% and phosphorus enrichment could be attained up to 3.46 times the stoichiometric value. Any further recirculation would reduce the sludge further but at the expense of enhanced phosphorus uptake as released phosphorus from side stream anaerobic reactor also recycled back to main SBR causing looping and at more than 6.41gVSSrecycled/gVSS it nullified the enhanced effect.
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Affiliation(s)
- Anwar Khursheed
- Department of Civil Engineering, College of Engineering, KSU, Riyadh, 11421, Saudi Arabia; Department of Civil Engineering, Z.H. College of Engineering, AMU, Aligarh, India.
| | | | | | - Abdulrhman Fahmi Alali
- Department of Civil Engineering, College of Engineering, KSU, Riyadh, 11421, Saudi Arabia
| | - Mohab Amin Kamal
- Department of Civil Engineering, College of Engineering, KSU, Riyadh, 11421, Saudi Arabia
| | - Shamshad Alam
- Department of Civil Engineering, College of Engineering, KSU, Riyadh, 11421, Saudi Arabia
| | - Omar Alrehaili
- Department of Civil Engineering, College of Engineering, KSU, Riyadh, 11421, Saudi Arabia
| | - Dar Tafazul Islam
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology, Delhi, India
| | - Manish Kumar
- Discipline of Earth Sciences, Indian Institute of Technology, Gandhinagar, 382355, India; Escuela de Ingeniería y Ciencias, Tecnologico de Monterrey, Campus Monterey, Monterrey, 64849, Nuevo Leon, Mexico
| | - Sunita Varjani
- Gujarat Pollution Control Board, Gandhinagar, 382 010, Gujarat, India
| | - A A Kazmi
- Department of Civil Engineering, Indian Institute of Technology, Roorkee, 247667, India
| | - Vinay Kumar Tyagi
- Environmental Hydrology Division, National Institute of Hydrology Roorkee, Roorkee, Uttarakhand, 247667, India.
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16
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Manyi-Loh CE, Okoh AI, Lues R. Prevalence of Multidrug-Resistant Bacteria (Enteropathogens) Recovered from a Blend of Pig Manure and Pinewood Saw Dust during Anaerobic Co-Digestion in a Steel Biodigester. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:984. [PMID: 36673737 PMCID: PMC9859553 DOI: 10.3390/ijerph20020984] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 12/19/2022] [Accepted: 01/02/2023] [Indexed: 06/17/2023]
Abstract
South Africa adopts intensive livestock farming, embracing the employment of huge quantities of antibiotics to meet the increased demand for meat. Therefore, bacteria occurring in the animal products and manure might develop antibiotic resistance, a scenario which threatens public health. The study investigated the occurrence of Gram-negative bacteria from eighteen pooled samples withdrawn from a single-stage steel biodigester co-digesting pig manure (75%) and pine wood saw dust (25%). The viable counts for each bacterium were determined using the spread plate technique. The bacterial isolates were characterised based on cultural, morphological and biochemical characteristics, using the Analytical Profile Index 20 e test kit. In addition, isolates were characterised based on susceptibility to 14 conventional antibiotics via the disc diffusion method. The MAR index was calculated for each bacterial isolate. The bacterial counts ranged from 104 to 106 cfu/mL, indicating manure as a potential source of contamination. Overall, 159 bacterial isolates were recovered, which displayed diverse susceptibility patterns with marked sensitivity to amoxicillin (100% E. coli), streptomycin (96.15% for Yersinia spp.; 93.33% for Salmonella spp.) and 75% Campylobacter spp. to nitrofurantoin. Varying resistance rates were equally observed, but a common resistance was demonstrated to erythromycin (100% of Salmonella and Yersinia spp.), 90.63% of E. coli and 78.57% of Campylobacter spp. A total of 91.19% of the bacterial isolates had a MAR index > 0.2, represented by 94 MAR phenotypes. The findings revealed multidrug resistance in bacteria from the piggery source, suggesting they can contribute immensely to the spread of multidrug resistance; thus, it serves as a pointer to the need for the enforcement of regulatory antibiotic use in piggery farms. Therefore, to curb the level of multidrug resistance, the piggery farm should implement control measures in the study area.
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Affiliation(s)
- Christy Echakachi Manyi-Loh
- Centre of Applied Food Sustainability and Biotechnology (CAFSaB), Central University of Technology, Bloemfontein 9301, South Africa
| | - Anthony Ifeanyin Okoh
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice 5700, South Africa
- Department of Environmental Health Sciences, College of Health Sciences, University of Sharjah, Sharjah P.O. Box 26666, United Arab Emirates
| | - Ryk Lues
- Centre of Applied Food Sustainability and Biotechnology (CAFSaB), Central University of Technology, Bloemfontein 9301, South Africa
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17
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Li L, Wang K, Sun Z, Zhao Q, Zhou H, Gao Q, Jiang J, Mei W. Effect of optimized intermittent mixing during high-solids anaerobic co-digestion of food waste and sewage sludge: Simulation, performance, and mechanisms. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 842:156882. [PMID: 35753448 DOI: 10.1016/j.scitotenv.2022.156882] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 06/01/2022] [Accepted: 06/18/2022] [Indexed: 06/15/2023]
Abstract
Inadequate mixing has been proven to be a major cause of anaerobic digester failure. This study revealed the mechanism of mixing intervals on high-solids anaerobic co-digestion (HS-AcoD) of food waste (FW) and sewage sludge (SS). Optimized intermittent mixing time (15 min/h) was determined through computational fluid dynamics (CFD) simulation. Experimental results indicated that the simulated intermittent mixing could shorten digestion time and increase cumulative methane output (366.8 mL/gVS) compared with continuous mixing and unmixing. Mixing could considerably accelerate substrate solubilization and hydrolysis. Maximum rates of acidogenesis (53.35 %) and methanogenesis (49.41 %) were observed with an optimized intermittent mixing (15 min/h). Vigorous mixing induced apoptosis and disrupted syntrophic metabolism, whereas intermittent mixing promoted the syntrophic metabolism between Syntrophomonas and Methanobacterium, and led to an enrichment of genes involved in acidogenic and methanogenic pathways. These findings have important implications for the development of an optimized intermittent mixing strategy for maximizing HS-AcoD efficiency of FW and SS.
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Affiliation(s)
- Lili Li
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Kun Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Zhijian Sun
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Qingliang Zhao
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China.
| | - Huimin Zhou
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Qingwei Gao
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Junqiu Jiang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Wangyang Mei
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
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18
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Körber M, Weinrich S, Span R, Gerber M. Demand-oriented biogas production to cover residual load of an electricity self-sufficient community using a simple kinetic model. BIORESOURCE TECHNOLOGY 2022; 361:127664. [PMID: 35872271 DOI: 10.1016/j.biortech.2022.127664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 07/15/2022] [Accepted: 07/17/2022] [Indexed: 06/15/2023]
Abstract
Flexible biogas production can enable demand-oriented energy supply without the need for expensive gas storage expansions, but poses challenges to the stability of the anaerobic digestion (AD) process. In this work, biogas production of laboratory-scale AD of maize silage and sugar beets was optimized to cover the residual load of an electricity self-sufficient community using a simple process model based on first-order kinetics. Experiments show a good agreement between biogas demand, predicted, and measured biogas production. By optimizing biogas conversion schedules based on the measured gas production, a gas storage capacity of 7-8 h was identified for maximum flexibility, which corresponds to typical gas storage sizes at industrial biogas plants in Germany. Various stability indicators were continuously monitored and proved resilient process conditions. These results demonstrate that demand-oriented biogas production using model predictive control is a promising approach to enable existing biogas plants to provide balancing energy.
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Affiliation(s)
- Matthias Körber
- Thermodynamics, Ruhr-University Bochum, Universitätsstraße 150, 44801 Bochum, Germany.
| | - Sören Weinrich
- Biochemical Conversion Department, Deutsches Biomasseforschungszentrum gemeinnützige GmbH, Torgauer Straße 116, 04347 Leipzig, Germany
| | - Roland Span
- Thermodynamics, Ruhr-University Bochum, Universitätsstraße 150, 44801 Bochum, Germany
| | - Mandy Gerber
- Mechatronics and Mechanical Engineering, Bochum University of Applied Sciences, Am Hochschulcampus 1, 44801 Bochum, Germany
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19
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Zhan Y, Cao X, Xiao Y, Wei X, Wu S, Zhu J. Start-up of co-digestion of poultry litter and wheat straw in anaerobic sequencing batch reactor by gradually increasing organic loading rate: Methane production and microbial community analysis. BIORESOURCE TECHNOLOGY 2022; 354:127232. [PMID: 35483532 DOI: 10.1016/j.biortech.2022.127232] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 04/22/2022] [Accepted: 04/23/2022] [Indexed: 05/23/2023]
Abstract
Anaerobic co-digestion (ACoD) of poultry litter (PL) and wheat straw (WS) in an anaerobic sequencing batch reactor (ASBR) for continuous bio-energy generation was started up for the first time by gradually increasing the organic loading rate (OLR). A steady-state was reached with a daily biogas production of (13.06 ± 0.21) L and methane content of (54.38 ± 0.53) %. The subsequent regular operation achieved a daily methane yield of (100.41-188.65) mL CH4/g VS added and a total chemical oxygen demand (tCOD) removal rate of (70.3-85.9) % in the effluent under different operating parameters. The overall microbial community became more uniform, and the dominant aceticlastic methanogen of Methanosaeta was enriched after the start-up. While the microbial community was largely stable in the overall structure since the regular operation. Therefore, the start-up of the ACoD of PL and WS was successful with stable and continuous methane production.
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Affiliation(s)
- Yuanhang Zhan
- Department of Biological and Agricultural Engineering, University of Arkansas, Fayetteville, AR 72701, USA.
| | - Xiaoxia Cao
- Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, Belfast BT9 5DL, UK
| | - Yiting Xiao
- Department of Biological and Agricultural Engineering, University of Arkansas, Fayetteville, AR 72701, USA
| | - Xiaoyuan Wei
- Department of Animal Science, University of Arkansas, Fayetteville, AR 72701, USA
| | - Sarah Wu
- Department of Chemical and Biological Engineering, University of Idaho, Moscow, ID 83844, USA
| | - Jun Zhu
- Department of Biological and Agricultural Engineering, University of Arkansas, Fayetteville, AR 72701, USA
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20
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Park MJ, Kim HM, Lee YH, Jeon KW, Jeong DW. Optimization of a renewable hydrogen production system from food waste: A combination of anaerobic digestion and biogas reforming. WASTE MANAGEMENT (NEW YORK, N.Y.) 2022; 144:272-284. [PMID: 35421707 DOI: 10.1016/j.wasman.2022.03.028] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2022] [Revised: 03/14/2022] [Accepted: 03/29/2022] [Indexed: 06/14/2023]
Abstract
In this study, hydrogen production using food waste was optimized by investigating the effect of agitator types in anaerobic digestion reactors and catalysts for biogas reforming. The applied agitators were pitched blade and hydrofoil, and their effect on homogeneity was estimated using computational fluid dynamics. Reactors with different agitators were operated for 60 days for biogas production. Increased biogas production was observed in the reactor equipped with a hydrofoil agitator owing to its high homogeneity. In addition, Ni-CeZrO2 catalysts promoted with La2O3, CaO, or MgO were investigated for stable hydrogen production during the biogas reforming reaction using simulated gas based on biogas from the anaerobic digestion equipped the hydrofoil. Among the promoted catalysts, the MgO-promoted Ni-CeZrO2 catalyst displayed the best results for hydrogen production without significant deactivation. The stable catalytic performance of the MgO-promoted catalyst resulted from the close interaction between Ni and MgO, and its high oxygen storage capacity. Thus, 1216 L hydrogen and 646 L carbon monoxide were produced per kilogram volatile solid via the hydrogen production system that included anaerobic digestion and biogas reforming.
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Affiliation(s)
- Min-Ju Park
- Department of Smart Environmental Energy Engineering, Changwon National University, 20 Changwondaehak-ro, Changwon, Gyeongnam 51140, Republic of Korea
| | - Hak-Min Kim
- Industrial Technology Research Center, Changwon National University, 20 Changwondaehak-ro, Changwon, Gyeongnam 51140, Republic of Korea
| | - Yong-Hee Lee
- Department of Smart Environmental Energy Engineering, Changwon National University, 20 Changwondaehak-ro, Changwon, Gyeongnam 51140, Republic of Korea
| | - Kyung-Won Jeon
- Department of Environmental and Energy Engineering, Kyungnam University, 7, Kyungnamdaehak-ro, Changwon, Gyeongsangnam-do, Republic of Korea
| | - Dae-Woon Jeong
- Department of Smart Environmental Energy Engineering, Changwon National University, 20 Changwondaehak-ro, Changwon, Gyeongnam 51140, Republic of Korea; Department of Environment & Energy Engineering, Changwon National University, 20 Changwondaehak-ro, Changwon, Gyeongnam 51140, Republic of Korea.
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21
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Khan A, Akbar S, Okonkwo V, Smith C, Khan S, Ali Shah A, Adnan F, Zeeshan Ijaz U, Ahmed S, Badshah M. Enrichment of the hydrogenotrophic methanogens for, in-situ biogas up-gradation by recirculation of gases and supply of hydrogen in methanogenic reactor. BIORESOURCE TECHNOLOGY 2022; 345:126219. [PMID: 34813923 DOI: 10.1016/j.biortech.2021.126219] [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: 08/31/2021] [Revised: 10/20/2021] [Accepted: 10/22/2021] [Indexed: 06/13/2023]
Abstract
During in situ biogas up-gradation by supplying hydrogen from an external source and enrichment of hydrogenotrophic methanogens, high pressure of H2 negatively affects hydrolytic and fermentative activities. To overcome this problem, the present study aimed to enrich the hydrogenotrophic methanogens by optimization of various parameters associated with gas recirculation along-with hydrogen supply from the external source. Due to recirculation of gases and supplied hydrogen, methane generation was two-fold higher in the optimal condition than in conventional anaerobic digestion, with the highest methane content of 99%. Additionally, the hydrogenotrophic methanogens were enriched, with a decrease in acetoclastic methanogens and an increase in Bathyarchaeia population, which utilizes H2 and CO2 to produce acetate and lactate as end products. The study concludes that recirculation increases methane production by converting H2 and CO2 into methane and enhances the degradation of organic matter left over undigested in the hydrolytic reactor.
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Affiliation(s)
- Alam Khan
- Sustainable Bioenergy and Biorefinery Laboratory, Department of Microbiology, Quaid-i-Azam University, Islamabad 45320, Pakistan
| | - Sedrah Akbar
- Sustainable Bioenergy and Biorefinery Laboratory, Department of Microbiology, Quaid-i-Azam University, Islamabad 45320, Pakistan
| | - Valentine Okonkwo
- Water Engineering Group, School of Engineering, The University of Glasgow, Glasgow, United Kingdom
| | - Cindy Smith
- Water Engineering Group, School of Engineering, The University of Glasgow, Glasgow, United Kingdom; Department of Microbiology, School of Natural Sciences, National University of Ireland Galway, Galway H91 TK33, Ireland
| | - Samiullah Khan
- Sustainable Bioenergy and Biorefinery Laboratory, Department of Microbiology, Quaid-i-Azam University, Islamabad 45320, Pakistan
| | - Aamer Ali Shah
- Sustainable Bioenergy and Biorefinery Laboratory, Department of Microbiology, Quaid-i-Azam University, Islamabad 45320, Pakistan
| | - Fazal Adnan
- Atta-ur-Rahman School of Applied Biosciences, National University of Sciences & Technology, Islamabad, Pakistan
| | - Umer Zeeshan Ijaz
- Water Engineering Group, School of Engineering, The University of Glasgow, Glasgow, United Kingdom
| | - Safia Ahmed
- Sustainable Bioenergy and Biorefinery Laboratory, Department of Microbiology, Quaid-i-Azam University, Islamabad 45320, Pakistan
| | - Malik Badshah
- Sustainable Bioenergy and Biorefinery Laboratory, Department of Microbiology, Quaid-i-Azam University, Islamabad 45320, Pakistan.
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22
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Shekhar Bose R, Chowdhury B, Zakaria BS, Kumar Tiwari M, Ranjan Dhar B. Significance of different mixing conditions on performance and microbial communities in anaerobic digester amended with granular and powdered activated carbon. BIORESOURCE TECHNOLOGY 2021; 341:125768. [PMID: 34469818 DOI: 10.1016/j.biortech.2021.125768] [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: 06/16/2021] [Revised: 08/06/2021] [Accepted: 08/10/2021] [Indexed: 06/13/2023]
Abstract
Conductive materials amendment in anaerobic digestion (AD) is a promising strategy for boosting the methanogenesis process. Despite mixing is a critical parameter, the behavior of digesters amended with conductive additives upon different mixing conditions has rarely been investigated. This study investigated continuous mixing, intermittent mixing (10 min in every 12 h), and non-mixing conditions for digesters amended with granular activated carbon (GAC) and powdered activated carbon (PAC). The non-mixed GAC digester provided the highest methane yield (318 ± 28 mL/g COD) from synthetic blackwater, while intermittently mixed GAC and control exhibited similar methane yields (290-294 mL/g COD). For non-mixed systems, microbial richness and diversity increased with GAC and PAC amendment. In contrast, continuous and intermittent mixing increased microbial diversity and richness in control reactors while reduced the same in GAC and PAC amended reactors. Overall, various mixing conditions distinctly changed the degree of enrichment/retention of microbes and consequently influenced methane recovery.
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Affiliation(s)
- Raj Shekhar Bose
- Civil and Environmental Engineering, University of Alberta, Edmonton AB, Canada; School of Water Resources, Indian Institute of Technology Kharagpur, WB, India
| | - Bappi Chowdhury
- Civil and Environmental Engineering, University of Alberta, Edmonton AB, Canada
| | - Basem S Zakaria
- Civil and Environmental Engineering, University of Alberta, Edmonton AB, Canada
| | - Manoj Kumar Tiwari
- School of Water Resources, Indian Institute of Technology Kharagpur, WB, India
| | - Bipro Ranjan Dhar
- Civil and Environmental Engineering, University of Alberta, Edmonton AB, Canada.
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23
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Enhancing Efficiency of Anaerobic Digestion by Optimization of Mixing Regimes Using Helical Ribbon Impeller. FERMENTATION 2021. [DOI: 10.3390/fermentation7040251] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The appropriate mixing system and approach to effective management can provide favorable conditions for the highly sensitive microbial community, which can ensure process stability and efficiency in an anaerobic digester. In this study, the effect of mixing intensity on biogas production in a lab-scale anaerobic digester has been investigated experimentally and via modeling. Considering high mixing efficiency and unique feature of producing axial flow, helical ribbon (HR) impeller is used for mixing the slurry in this experiment under various conditions. Three parallel digesters were analyzed under identical operating conditions for comparative study and high accuracy. Effects of different mixing speeds (10, 30, and 67 rpm for 5 min h−1) on biogas production rate were determined in 5-L lab-scale digesters. The results demonstrated 15–18% higher biogas production at higher mixing speed (67 rpm) as compared to 10 rpm and 30 rpm and the results proved statistically significant (p < 0.05). Biogas production at 10, 30, and 67 rpm were 45.6, 48.6, and 52.5 L, respectively. Higher VFA concentrations (7.67 g L−1) were recorded at lower mixing intensity but there was no significant difference in pH and ammonia at different speeds whereas the better mixing efficiency at higher speeds was also the main reason for increase in biogas production. Furthermore, model simulation calculations revealed the reduction of dead zones and better homogeneous mixing at higher mixing speeds. Reduction of dead zones from 18% at 10 rpm to 2% at 67 rpm was observed, which can be the major factor in significant difference in biogas production rates at various mixing intensities. Optimization of digester and impeller geometry should be a prime focus to scale-up digesters and to optimize mixing in full-scale digesters.
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Ohnmacht B, Lemmer A, Oechsner H, Kress P. Demand-oriented biogas production and biogas storage in digestate by flexibly feeding a full-scale biogas plant. BIORESOURCE TECHNOLOGY 2021; 332:125099. [PMID: 33862386 DOI: 10.1016/j.biortech.2021.125099] [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: 01/31/2021] [Revised: 03/24/2021] [Accepted: 03/26/2021] [Indexed: 06/12/2023]
Abstract
This work studied the demand-oriented biogas production and the biogas storage in digestate by flexibly feeding a full-scale research biogas plant. The investigated continuous stirred tank reactor (CSTR) was equipped with a fast-moving submersible motor mixer and a slow-moving inclined shaft agitator. A model for the biogas storage in digestate was introduced and tested in full scale using temporally highly resolved volume flow measurements. An increase in mixing time led to a faster biogas production: A two to five hours reduction of the time to reach the maximum biogas production after feeding occurred in our experiments. However, no influence of the rheology and of the mixing regime on the methane yield could be derived from the measurements. Further, a 30% reduction of the stored biogas in the digestate occurred when the viscosity was lowered by 66%. This knowledge can be used to enhance the existing biogas formation models.
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Affiliation(s)
- Benjamin Ohnmacht
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstr. 9, Stuttgart 70599, Germany.
| | - Andreas Lemmer
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstr. 9, Stuttgart 70599, Germany
| | - Hans Oechsner
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstr. 9, Stuttgart 70599, Germany
| | - Philipp Kress
- University of Hohenheim, State Institute of Agricultural Engineering and Bioenergy, Garbenstr. 9, Stuttgart 70599, Germany
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Oliveros-Muñoz JM, Martínez-Villalba JA, Jiménez-Islas H, Luna-Porres MY, Escamilla-Alvarado C, Ríos-Fránquez FJ. Luus-Jaakola method and ADM1 based optimization of hydrogen sulfide in anaerobic digestion of cow manure. Biochem Eng J 2021. [DOI: 10.1016/j.bej.2021.108012] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Methodological Approaches to Optimising Anaerobic Digestion of Water Hyacinth for Energy Efficiency in South Africa. SUSTAINABILITY 2021. [DOI: 10.3390/su13126746] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Anaerobic digestion has been identified as a feasible fragment of a bioeconomy, yet numerous factors hinder the adoption of the technology in South Africa. Apart from its energy recovery, other nonmarket advantages support the technology. Though it may be challenging to have a price tag, they provide clear added worth for such investments. With a growing energy demand and global energy transitions, there is a need to sustainably commercialise the biogas industry in South Africa. Most studies are at laboratory scale and under specific conditions, which invariably create gaps in using their data for commercialising the biogas technology. The key to recognising these gaps depends on knowing the crucial technical phases that have the utmost outcome on the economics of biogas production. This study is a meta-analysis of the optimisation of anaerobic digestion through methodological approaches aimed at enhancing the production of biogas. This review, therefore, argues that regulating the fundamental operational parameters, understanding the microbial community’s interactions, and modelling the anaerobic processes are vital indicators for improving the process stability and methane yield for the commercialisation of the technology. It further argues that South Africa can exploit water hyacinth as a substrate for a self-sufficient biogas production system in a bid to mitigate the invasive alien plants.
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Singh A, Kumar V. Recent developments in monitoring technology for anaerobic digesters: A focus on bio-electrochemical systems. BIORESOURCE TECHNOLOGY 2021; 329:124937. [PMID: 33712339 DOI: 10.1016/j.biortech.2021.124937] [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: 01/31/2021] [Revised: 02/27/2021] [Accepted: 03/01/2021] [Indexed: 06/12/2023]
Abstract
With the increasing popularity of waste to energy conversion, demand for large-scale operation of anaerobic digestors has emerged in the market. However, the process instabilities in anaerobic digestors limit the expansion of facilities to high loading rates. The irregularities in the process can be addressed directly by altering the feedstock characteristics provided an on-hand, robust, and sensitive monitoring device is available. In this context, the bioelectrochemical system has emerged as an excellent tool for monitoring and optimizing the anaerobic process within the reactor. This article reviews the gradual evolution in techniques and approaches for monitoring of anaerobic digestion (AD) process. An analysis of the recently popular biosensing techniques has been done with a focus on the bioelectrochemical monitoring system and its operation mode. A brief attempt to highlight the current challenges in the field of bioelectrochemical process monitoring for AD has also been made, which can be supportive of future research.
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Affiliation(s)
- Ankur Singh
- Department of Environmental Science and Engineering, Indian Institute of Technology (Indian School of Mines), Dhanbad, Jharkhand 826004, India
| | - Vipin Kumar
- Department of Environmental Science and Engineering, Indian Institute of Technology (Indian School of Mines), Dhanbad, Jharkhand 826004, India.
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Wang P, Sakhno Y, Adhikari S, Peng H, Jaisi D, Soneye T, Higgins B, Wang Q. Effect of ammonia removal and biochar detoxification on anaerobic digestion of aqueous phase from municipal sludge hydrothermal liquefaction. BIORESOURCE TECHNOLOGY 2021; 326:124730. [PMID: 33548815 DOI: 10.1016/j.biortech.2021.124730] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 01/08/2021] [Accepted: 01/12/2021] [Indexed: 06/12/2023]
Abstract
Hydrothermal liquefaction is a promising method to convert municipal sludge into an energy-dense fuel. The inevitable by-product aqueous phase is rich in complex organics, which has the potential for energy and nutrient recovery and can be treated by anaerobic digestion to produce methane. However, toxic compounds such as ammonia and phenolics present would inhibit the function of micro-organisms. This study investigated the influence of ammonia and phenolics removal on anaerobic digestion. The results showed that the treated aqueous phase resulted in up to 225 ml CH4/g COD. The highest methane production was obtained in the culture with both ammonia and phenolics removal at pH 7.0, which was about 90% higher than only ammonia removal and seven times higher than only phenolics removal. The microbial community analysis results showed that these two treatments could increase microbial diversity and upregulate the relative abundance of methanogens.
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Affiliation(s)
- Pixiang Wang
- Department of Biosystems Engineering, Auburn University, Auburn, AL 36849, USA
| | - Yuriy Sakhno
- Plant & Soil Sciences Department, University of Delaware, Newark, DE 19713, USA
| | - Sushil Adhikari
- Department of Biosystems Engineering, Auburn University, Auburn, AL 36849, USA; Center for Bioenergy and Bioproducts, Auburn University, Auburn, AL 36849, USA.
| | - Haixin Peng
- Department of Biosystems Engineering, Auburn University, Auburn, AL 36849, USA
| | - Deb Jaisi
- Plant & Soil Sciences Department, University of Delaware, Newark, DE 19713, USA
| | - Temitope Soneye
- Department of Biosystems Engineering, Auburn University, Auburn, AL 36849, USA
| | - Brendan Higgins
- Department of Biosystems Engineering, Auburn University, Auburn, AL 36849, USA
| | - Qichen Wang
- Department of Biosystems Engineering, Auburn University, Auburn, AL 36849, USA
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Biomethanation Potential (BMP) Study of Mesophilic Anaerobic Co-Digestion of Abundant Bio-Wastes in Southern Regions of Tunisia. Processes (Basel) 2020. [DOI: 10.3390/pr9010048] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Tunisia is a country that suffers from energy demand problems and environmental matters. Thus, Tunisian authorities desire to encourage the development of renewable energy sources, especially from biological processes, like anaerobic digestion. Therefore, this study is focused on the evaluation of biogas and bio-methane yield from the co-digestion of three available and abundant bio-wastes in the southern regions of Tunisia. The three different raw materials are an organic fraction of municipal solid waste, chicken manure, and olive mill wastewater. In this context, experimental work to evaluate the potential of biogas and bio-methane production was carried out at mesophilic temperature 35 °C and batch mode. The present work highlights the possibility of generating biogas from these organic wastes and reducing the amounts of the wastes to dispose of in landfills. The experimental study of the co-digestion process under specific conditions of carbon to nitrogen ratio (C/N), T, pH, and inoculums to substrate ratio ISR provided a high yield of net methane and net biogas, in comparison with other research works. Results showed a higher specific net methane production per kg of volatile solids, which is equal to 0.338 Nm3 methane/kg VS and 0.430 Nm3 methane/kg VS for two studied cases. The obtained volatile solids reduction was found to be 91% of the initial content, for a hydraulic retention time (HRT) of 40 days.
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Bergamo U, Viccione G, Coppola S, Landi A, Meda A, Gualtieri C. Analysis of anaerobic digester mixing: comparison of long shafted paddle mixing vs gas mixing. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2020; 81:1406-1419. [PMID: 32616693 DOI: 10.2166/wst.2020.248] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The anaerobic digestion (AD) process is influenced by a variety of operation parameters, such as sludge rheology, mixing, temperature, solid retention time (SRT), hydraulic retention time (HRT) and solids concentration. The optimum in the mixing lies somewhere between no-mixing and continuous mixing, as the lack or excessive mixing can lead to poor AD performance instead. A three-dimensional computational fluid dynamics steady/unsteady model, incorporating the rheological properties of the sludge, was developed and applied to quantify mixing in a full-scale anaerobic digester. Mechanical and gas mixing solutions were taken into account, keeping constant the daily energy consumption. Results, consisting of velocity magnitude and patterns, dead zone formation and turbulence levels were discussed. Compared to the mechanical mixing, gas mixing had lower percentage of dead zones (about 5% against 50%), larger maximum velocity (about 3 m/s against 1 m/s) as well as larger turbulent kinetic energy levels (0.24 m2/s2 against 0.001 m2/s2).
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Affiliation(s)
- U Bergamo
- Department of Civil Engineering, University of Salerno, via Giovanni Paolo II, 132, 84084 Fisciano, Italy E-mail:
| | - G Viccione
- Department of Civil Engineering, University of Salerno, via Giovanni Paolo II, 132, 84084 Fisciano, Italy E-mail:
| | - S Coppola
- Department of Civil Engineering, University of Salerno, via Giovanni Paolo II, 132, 84084 Fisciano, Italy E-mail:
| | - A Landi
- MEA S.R.L., Foro Buonaparte, 70, 20121, Milano, Italy
| | - A Meda
- BHU Umwelttechnik GmbH, Einsteinstrasse 57, 70229 Leonberg, Germany
| | - C Gualtieri
- Department of Civil, Architectural and Environmental Engineering, University of Naples Federico II, via Claudio, 21, 80125 Naples, Italy
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