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Kozhakhmetova M, Akimbekov N, Digel I, Tastambek K. Evaluating the low-rank coal degradation efficiency bioaugmented with activated sludge. Sci Rep 2024; 14:14827. [PMID: 38937498 PMCID: PMC11211346 DOI: 10.1038/s41598-024-64275-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Accepted: 06/06/2024] [Indexed: 06/29/2024] Open
Abstract
Microbial bioaugmentation of coal is considered as a viable and ecologically sustainable approach for the utilization of low-rank coals (LRC). The search for novel techniques to derive high-value products from LRC is currently of great importance. In response to this demand, endeavors have been undertaken to develop microbially based coal solubilization and degradation techniques. The impact of supplementing activated sludge (AS) as a microbial augmentation to enhance LRC biodegradation was investigated in this study. The LRC and their biodegradation products were characterized using the following methods: excitation-emission Matrices detected fluorophores at specific wavelength positions (O, E, and K peaks), revealing the presence of organic complexes with humic properties. FTIR indicated the increased amount of carboxyl groups in the bioaugmented coals, likely due to aerobic oxidation of peripheral non-aromatic structural components of coal. The bacterial communities of LRC samples are primarily composed of Actinobacteria (up to 36.2%) and Proteobacteria (up to 25.8%), whereas the Firmicutes (63.04%) was the most abundant phylum for AS. The community-level physiological profile analysis showed that the microbial community AS had high metabolic activity of compared to those of coal. Overall, the results demonstrated successful stimulation of LRC transformation through supplementation of exogenous microflora in the form of AS.
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Affiliation(s)
| | - Nuraly Akimbekov
- Al-Farabi Kazakh National University, 050040, Almaty, Kazakhstan
- Khoja Akhmet Yassawi International Kazakh-Turkish University, 161200, Turkestan, Kazakhstan
- West Kazakhstan Marat Ospanov Medical University, Maresyev Str. 68, 030019, Aktobe, Kazakhstan
| | - Ilya Digel
- Aachen University of Applied Sciences, Heinrich-Mussmann-Straße 1, 52428, Jülich, Germany
| | - Kuanysh Tastambek
- Al-Farabi Kazakh National University, 050040, Almaty, Kazakhstan
- Khoja Akhmet Yassawi International Kazakh-Turkish University, 161200, Turkestan, Kazakhstan
- M. Auezov South Kazakhstan University, 160012, Shymkent, Kazakhstan
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He J, Xia S, Li W, Deng J, Lin Q, Zhang L. Resource recovery and valorization of food wastewater for sustainable development: An overview of current approaches. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 347:119118. [PMID: 37769472 DOI: 10.1016/j.jenvman.2023.119118] [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: 04/19/2023] [Revised: 07/05/2023] [Accepted: 08/30/2023] [Indexed: 09/30/2023]
Abstract
The food processing industry is one of the world's largest consumers of potable water. Agri-food wastewater systems consume about 70% of the world's fresh water and cause at least 80% of deforestation. Food wastewater is characterized by complex composition, a wide range of pollutants, and fluctuating water quality, which can cause huge environmental pollution problems if discharged directly. In recent years, food wastewater has attracted considerable attention as it is considered to have great prospects for resource recovery and reuse due to its rich residues of nutrients and low levels of harmful substances. This review explored and compared the sources and characteristics of different types of food wastewater and methods of wastewater treatment. Particular attention was paid to the different methods of resource recovery and reuse of food wastewater. The diversity of raw materials in the food industry leads to different compositional characteristics of wastewater, which determine the choice and efficiency of wastewater treatment methods. Physicochemical methods, and biological methods alone or in combination have been used for the efficient treatment of food wastewater. Current approaches for recycling and reuse of food wastewater include culture substrates, agricultural irrigation, and bio-organic fertilizers, recovery of high-value products such as proteins, lipids, biopolymers, and bioenergy to alleviate the energy crisis. Food wastewater is a promising substrate for resource recovery and reuse, and its valorization meets the current international policy requirements regarding food waste and environment protection, follows the development trend of the food industry, and is also conducive to energy conservation, emission reduction, and economic development. However, more innovative biotechnologies are necessary to advance the effectiveness of food wastewater treatment and the extent of resource recovery and valorization.
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Affiliation(s)
- JinTao He
- National Engineering Research Center of Rice and Byproduct Deep Processing, Hunan Province Key Laboratory of Edible Forestry Resources Safety and Processing Utilization, College of Food Science and Engineering, Central South University of Forestry and Technology, Changsha, 410004, Hunan, China
| | - SuXuan Xia
- National Engineering Research Center of Rice and Byproduct Deep Processing, Hunan Province Key Laboratory of Edible Forestry Resources Safety and Processing Utilization, College of Food Science and Engineering, Central South University of Forestry and Technology, Changsha, 410004, Hunan, China
| | - Wen Li
- National Engineering Research Center of Rice and Byproduct Deep Processing, Hunan Province Key Laboratory of Edible Forestry Resources Safety and Processing Utilization, College of Food Science and Engineering, Central South University of Forestry and Technology, Changsha, 410004, Hunan, China; Hunan Provincial Engineering Technology Research Center of Seasonings Green Manufacturing, China; College of Food Science and Engineering, Nanjing University of Finance and Economics/Collaborative Innovation Center for Modern Grain Circulation and Safety, Nanjing, 210023, Jiangsu, China.
| | - Jing Deng
- National Engineering Research Center of Rice and Byproduct Deep Processing, Hunan Province Key Laboratory of Edible Forestry Resources Safety and Processing Utilization, College of Food Science and Engineering, Central South University of Forestry and Technology, Changsha, 410004, Hunan, China
| | - QinLu Lin
- National Engineering Research Center of Rice and Byproduct Deep Processing, Hunan Province Key Laboratory of Edible Forestry Resources Safety and Processing Utilization, College of Food Science and Engineering, Central South University of Forestry and Technology, Changsha, 410004, Hunan, China; College of Food Science and Engineering, Nanjing University of Finance and Economics/Collaborative Innovation Center for Modern Grain Circulation and Safety, Nanjing, 210023, Jiangsu, China.
| | - Lin Zhang
- National Engineering Research Center of Rice and Byproduct Deep Processing, Hunan Province Key Laboratory of Edible Forestry Resources Safety and Processing Utilization, College of Food Science and Engineering, Central South University of Forestry and Technology, Changsha, 410004, Hunan, China
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Wang Y, Lin R, Cao Y, Li S, Cui R, Guo W, Ho SH, Kit Leong Y, Lee DJ, Chang JS. Simultaneous Removal of Sulfamethoxazole during Fermentative Production of Short-Chain Fatty Acids. BIORESOURCE TECHNOLOGY 2023:129317. [PMID: 37315625 DOI: 10.1016/j.biortech.2023.129317] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2023] [Revised: 06/08/2023] [Accepted: 06/10/2023] [Indexed: 06/16/2023]
Abstract
This study explores the simultaneous sulfamethoxazole (SMX) removal and short-chain fatty acids (SCFAs) production by a Clostridium sensu stricto-dominated microbial consortium. SMX is a commonly prescribed and persistent antimicrobial agent frequently detected in aquatic environments, while the prevalence of antibiotic-resistant genes limits the biological removal of SMX. Under strictly anaerobic conditions, sequencing batch cultivation coupled with co-metabolism resulted in the production of butyric acid, valeric acid, succinic acid, and caproic acid. Continuous cultivation in a CSTR achieved a maximum butyric acid production rate and yield of 0.167 g/L/h and 9.56 mg/g COD, respectively, while achieving a maximum SMX degradation rate and removal capacity of 116.06 mg/L/h and 55.8 g SMX/g biomass. Furthermore, continuous anaerobic fermentation reduced sul genes prevalence, thus limiting the transmission of antibiotic resistance genes during antibiotic degradation. These findings suggest a promising approach for efficient antibiotic elimination while simultaneously producing valuable products (e.g., SCFAs).
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Affiliation(s)
- Yue Wang
- School of Environmental and Materials Engineering, Yantai University, Yantai 264000, China
| | - Rongrong Lin
- School of Environmental and Materials Engineering, Yantai University, Yantai 264000, China
| | - Yushuang Cao
- School of Environmental and Materials Engineering, Yantai University, Yantai 264000, China
| | - Shuangfei Li
- College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China
| | - Rong Cui
- School of Environmental and Materials Engineering, Yantai University, Yantai 264000, China
| | - Wanqian Guo
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Shih-Hsin Ho
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Yoong Kit Leong
- Department of Chemical and Materials Engineering, Tunghai University, Taichung 407, Taiwan; Research Center for Smart Sustainable Circular Economy, Tunghai University, Taichung 407, Taiwan
| | - Duu-Jong Lee
- Department of Mechanical Engineering, City University of Hong Kong, Kowloon Tang, Hong Kong
| | - Jo-Shu Chang
- Department of Chemical and Materials Engineering, Tunghai University, Taichung 407, Taiwan; Research Center for Smart Sustainable Circular Economy, Tunghai University, Taichung 407, Taiwan; Department of Chemical Engineering, National Cheng Kung University, Tainan, Taiwan; Department of Chemical Engineering and Materials Science, Yuan Ze University, Chung-Li, Taiwan.
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Mills S, Yen Nguyen TP, Ijaz UZ, Lens PNL. Process stability in expanded granular sludge bed bioreactors enhances resistance to organic load shocks. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 342:118271. [PMID: 37269726 DOI: 10.1016/j.jenvman.2023.118271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2023] [Revised: 05/21/2023] [Accepted: 05/24/2023] [Indexed: 06/05/2023]
Abstract
Environmental perturbations such as changes in organic loading rate (OLR) can have deleterious effects on the anaerobic digestion process, leading to VFA accumulation and process failure. However, the operational history of a reactor, such as prior exposure to VFA build up, can impact a reactor's resistance to shock loads. In the present study, the effects of long term (>100 days) bioreactor (un)stability on OLR shock resistance were assessed. Three 4 L EGSB bioreactors were subjected to varying levels of process stability. Operational conditions such as OLR, temperature and pH were maintained stable in R1; R2 was subjected to a series of minor OLR perturbations and R3 was subjected to a series of non-OLR perturbations, including ammonium, temperature, pH and sulfide. The effect of these different operational histories on each reactor's resistance to a sudden 8-fold increase in OLR were assessed by monitoring COD removal efficiency and biogas production. The microbial communities of each reactor were monitored using 16S rRNA gene sequencing to understand the relationship between microbial diversity and reactor stability. It was determined that the stable (un-perturbed) reactor performed best in terms of its resistance to a large OLR shock, despite its lower microbial community diversity.
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Affiliation(s)
- Simon Mills
- National University of Ireland, Galway, University Road, Galway, H91 TK33, Ireland.
| | - Thi Phi Yen Nguyen
- National University of Ireland, Galway, University Road, Galway, H91 TK33, Ireland
| | - Umer Zeeshan Ijaz
- National University of Ireland, Galway, University Road, Galway, H91 TK33, Ireland; Water & Environment Research Group, University of Glasgow, Mazumdar-Shaw Advanced Research Centre, Glasgow G11 6EW, United Kingdom; Department of Molecular and Clinical Cancer Medicine, University of Liverpool, Liverpool L69 7BE, United Kingdom
| | - Piet N L Lens
- National University of Ireland, Galway, University Road, Galway, H91 TK33, Ireland.
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Owusu-Agyeman I, Plaza E, Elginöz N, Atasoy M, Khatami K, Perez-Zabaleta M, Cabrera-Rodríguez C, Yesil H, Tugtas AE, Calli B, Cetecioglu Z. Conceptual system for sustainable and next-generation wastewater resource recovery facilities. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 885:163758. [PMID: 37120021 DOI: 10.1016/j.scitotenv.2023.163758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 04/12/2023] [Accepted: 04/23/2023] [Indexed: 05/10/2023]
Abstract
Shifting the concept of municipal wastewater treatment to recover resources is one of the key factors contributing to a sustainable society. A novel concept based on research is proposed to recover four main bio-based products from municipal wastewater while reaching the necessary regulatory standards. The main resource recovery units of the proposed system include upflow anaerobic sludge blanket reactor for the recovery of biogas (as product 1) from mainstream municipal wastewater after primary sedimentation. Sewage sludge is co-fermented with external organic waste such as food waste for volatile fatty acids (VFAs) production as precursors for other bio-based production. A portion of the VFA mixture (product 2) is used as carbon sources in the denitrification step of the nitrification/denitrification process as an alternative for nitrogen removal. The other alternative for nitrogen removal is the partial nitrification/anammx process. The VFA mixture is separated with nanofiltration/reverse osmosis membrane technology into low-carbon VFAs and high-carbon VFAs. Polyhydroxyalkanoate (as product 3) is produced from the low-carbon VFAs. Using membrane contactor-based processes and ion-exchange techniques, high-carbon VFAs are recovered as one-type VFA (pure VFA) and in ester forms (product 4). The nutrient-rich fermented and dewatered biosolid is applied as a fertilizer. The proposed units are seen as individual resource recovery systems as well as a concept of an integrated system. A qualitative environmental assessment of the proposed resource recovery units confirms the positive environmental impacts of the proposed system.
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Affiliation(s)
- Isaac Owusu-Agyeman
- Department of Industrial Biotechnology, KTH Royal Institute of Technology, SE-106 91 Stockholm, Sweden.
| | - Elzbieta Plaza
- Department of Sustainable Development, Environmental Science and Engineering, KTH-Royal Institute of Technology, SE-100 44 Stockholm, Sweden
| | - Nilay Elginöz
- IVL Swedish Environmental Research Institute, Box 210 60, 100 31 Stockholm, Sweden
| | - Merve Atasoy
- UNLOCK, Wageningen University & Research and Technical University Delft, Wageningen and Delft, Stippeneng 2, 6708 WE Wageningen, the Netherlands
| | - Kasra Khatami
- Department of Industrial Biotechnology, KTH Royal Institute of Technology, SE-106 91 Stockholm, Sweden
| | - Mariel Perez-Zabaleta
- Department of Industrial Biotechnology, KTH Royal Institute of Technology, SE-106 91 Stockholm, Sweden
| | | | - Hatice Yesil
- Department of Environmental Engineering, Marmara University, Maltepe, 34854, Istanbul, Turkey
| | - A Evren Tugtas
- Department of Environmental Engineering, Marmara University, Maltepe, 34854, Istanbul, Turkey
| | - Baris Calli
- Department of Environmental Engineering, Marmara University, Maltepe, 34854, Istanbul, Turkey
| | - Zeynep Cetecioglu
- Department of Industrial Biotechnology, KTH Royal Institute of Technology, SE-106 91 Stockholm, Sweden
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Wang C, Wang Y, Chen Z, Wei W, Chen X, Mannina G, Ni BJ. A novel strategy for efficiently transforming waste activated sludge into medium-chain fatty acid using free nitrous acid. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 862:160826. [PMID: 36502988 DOI: 10.1016/j.scitotenv.2022.160826] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 11/30/2022] [Accepted: 12/06/2022] [Indexed: 06/17/2023]
Abstract
The global energy crisis is approaching due to rapid population growth and overexploitation of fossil fuels. Therefore, the development and use of new and renewable energy sources is already in the extreme urgency. This work developed a novel technology to efficiently produce renewable liquid bioenergy from discarded wastes, by effectively transforming sewage sludge into high-value medium chain fatty acids (MCFA). The maximum MCFA yield in the anaerobic sludge fermentation was revealed to be 10.6 times of control when utilizing sewage sludge with 1.78 mg-N/L free nitrous acid (FNA) pretreatment. The carbon flow from sewage sludge into MCFA in the fermentation system was significantly enhanced with appropriate levels (0.71-1.78 mg-N/L) of FNA pretreatment. Compared to FNA pretreatment, however, its direct addition severely inhibited total products (i.e., carboxylates and complex alcohols) generation because of the toxicity on live cells (decreasing to 8.3 %-13.9 %) in sludge. Kinetic models (one-substrate and two-substrate) were utilized to investigate the mechanism of MCFA promotion by FNA pretreatment on anaerobic sludge fermentation, in which linear relationship analysis between FNA-derived organic release and the fitted parameters were also performed. The results indicated that the conversion of refractory materials into rapidly bioavailable substrates for MCFA production contributed to increasing MCFA production rate and potential. Moreover, the relative abundances of functional microorganisms related to hydrolysis-acidification and chain elongation process increased under FNA pretreatment, further favoring the MCFA production. This study provides a novel and effective technology of sludge energy recovery that can achieve the next-generation sustainable sewage sludge management.
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Affiliation(s)
- Chen Wang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China
| | - Yun Wang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China
| | - Zhijie Chen
- School of Civil and Environmental Engineering, Centre for Technology in Water and Wastewater, University of Technology Sydney, Sydney, NSW 2007, Australia
| | - Wei Wei
- School of Civil and Environmental Engineering, Centre for Technology in Water and Wastewater, University of Technology Sydney, Sydney, NSW 2007, Australia.
| | - Xueming Chen
- Fujian Provincial Engineering Research Center of Rural Waste Recycling Technology, College of Environment and Safety Engineering, Fuzhou University, Fujian 350116, China
| | - Giorgio Mannina
- Engineering Department, Palermo University, Ed. 8 Viale delle Scienze, 90128 Palermo, Italy
| | - Bing-Jie Ni
- School of Civil and Environmental Engineering, Centre for Technology in Water and Wastewater, University of Technology Sydney, Sydney, NSW 2007, Australia
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Zhang C, Liu H, Wu P, Li J, Zhang J. Clostridium kluyveri enhances caproate production by synergistically cooperating with acetogens in mixed microbial community of electro-fermentation system. BIORESOURCE TECHNOLOGY 2023; 369:128436. [PMID: 36470493 DOI: 10.1016/j.biortech.2022.128436] [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: 10/24/2022] [Revised: 11/30/2022] [Accepted: 12/01/2022] [Indexed: 06/17/2023]
Abstract
As a chain elongation (CE) model strain, Clostridium kluyveri has been used in the studies of bioaugmentation of caproate production. However, its application in the novel electro-fermentation CE system for bioaugmentation is still unclear. In this study, the CE performances, with or without bioaugmentation and in conventional or electro-fermentation systems were compared. And the mechanism of electrochemical-bioaugmentation by constructing a co-culture of Acetobacterium woodii and Clostridium kluyveri were further verified. Results demonstrated that the bioaugmentation treatments have better CE performance, especially in electro-fermentation system, with a highest caproate concentration of 4.68 g·L-1. Mechanism analysis revealed that C. kluyveri responded to the electric field and emerged synergy with the acetogens, which was proved by the increases of C. kluyveri colonization and the acetogens abundance in biofilm and supported by the co-culture experiment. This study provides a novel insight of microbial synergy mechanism of C. kluyveri during CE bioaugmentation in electro-fermentation system.
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Affiliation(s)
- Chao Zhang
- School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, China
| | - He Liu
- School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, China; Jiangsu Key Laboratory of Anaerobic Biotechnology, Wuxi 214122, China; Jiangsu Collaborative Innovation Center of Water Treatment Technology and Material, Suzhou University of Science and Technology, 215011, China.
| | - Ping Wu
- School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, China
| | - Jing Li
- School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, China
| | - Jie Zhang
- School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, China
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Current Status and Prospects of Valorizing Organic Waste via Arrested Anaerobic Digestion: Production and Separation of Volatile Fatty Acids. FERMENTATION-BASEL 2022. [DOI: 10.3390/fermentation9010013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Volatile fatty acids (VFA) are intermediary degradation products during anaerobic digestion (AD) that are subsequently converted to methanogenic substrates, such as hydrogen (H2), carbon dioxide (CO2), and acetic acid (CH3COOH). The final step of AD is the conversion of these methanogenic substrates into biogas, a mixture of methane (CH4) and CO2. In arrested AD (AAD), the methanogenic step is suppressed to inhibit VFA conversion to biogas, making VFA the main product of AAD, with CO2 and H2. VFA recovered from the AAD fermentation can be further converted to sustainable biofuels and bioproducts. Although this concept is known, commercialization of the AAD concept has been hindered by low VFA titers and productivity and lack of cost-effective separation methods for recovering VFA. This article reviews the different techniques used to rewire AD to AAD and the current state of the art of VFA production with AAD, emphasizing recent developments made for increasing the production and separation of VFA from complex organic materials. Finally, this paper discusses VFA production by AAD could play a pivotal role in producing sustainable jet fuels from agricultural biomass and wet organic waste materials.
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Atasoy M, Cetecioglu Z. The effects of pH on the production of volatile fatty acids and microbial dynamics in long-term reactor operation. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 319:115700. [PMID: 35982552 DOI: 10.1016/j.jenvman.2022.115700] [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: 04/09/2022] [Revised: 07/05/2022] [Accepted: 07/05/2022] [Indexed: 06/15/2023]
Abstract
Volatile fatty acids, intermediate products of anaerobic digestion, are one of the most promising biobased products. In this study, the effects of acidic (pH 5), neutral (without pH adjustment) and alkali (pH 10) pH on production efficiency and composition of volatile fatty acids (VFAs) and bacterial community profile were analyzed. The anaerobic sequencing batch reactors were fed cheese production wastewater as substrate and inoculated by anaerobic granular seed sludge. The results showed that acidic pH improved VFA production yield (0.92 at pH 5; 0.42 at pH 10 and 0.21 gCOD/gVS at neutral pH). Furthermore, propionic acid was dominant under both pH 10 (64 ± 20%) and neutral pH (72 ± 8%), whereas, acetic acid (23 ± 20%4), propionic acid (22 ± 3%), butyric acid (21 ± 4%) and valeric acid (15 ± 8%) were almost equally distributed under pH 5. Adaptation of bacterial community to different pH conditions might steer the acid profile: Bacteroidetes (50.07 ± 2%) under pH 10, Proteobacteria (40.74 ± 7%) under neutral pH and Firmicutes (47.64 ± 9%) under pH 5 were the most dominant phylum, respectively. Results indicated pH plays a significant role in VFA production, acid composition, and bacterial community structure. However, in order to gain a concrete understanding effects of pH, characterization of intracellular and extracellular metabolites with dynamics of the microbial community is required.
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Affiliation(s)
- Merve Atasoy
- Department of Chemical Engineering, KTH Royal Institute of Technology, 100 44, Stockholm, Sweden; UNLOCK, Wageningen University and Research, 6708 PB, the Netherlands.
| | - Zeynep Cetecioglu
- Department of Chemical Engineering, KTH Royal Institute of Technology, 100 44, Stockholm, Sweden; Department of Industrial Biotechnology, KTH Royal Institute of Technology, AlbaNova University Center, 11421, Stockholm, Sweden
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