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Rawat M, Chauhan M, Pandey A. Extremophiles and their expanding biotechnological applications. Arch Microbiol 2024; 206:247. [PMID: 38713374 DOI: 10.1007/s00203-024-03981-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 04/16/2024] [Accepted: 04/25/2024] [Indexed: 05/08/2024]
Abstract
Microbial life is not restricted to any particular setting. Over the past several decades, it has been evident that microbial populations can exist in a wide range of environments, including those with extremes in temperature, pressure, salinity, and pH. Bacteria and Archaea are the two most reported types of microbes that can sustain in extreme environments, such as hot springs, ice caves, acid drainage, and salt marshes. Some can even grow in toxic waste, organic solvents, and heavy metals. These microbes are called extremophiles. There exist certain microorganisms that are found capable of thriving in two or more extreme physiological conditions simultaneously, and are regarded as polyextremophiles. Extremophiles possess several physiological and molecular adaptations including production of extremolytes, ice nucleating proteins, pigments, extremozymes and exopolysaccharides. These metabolites are used in many biotechnological industries for making biofuels, developing new medicines, food additives, cryoprotective agents etc. Further, the study of extremophiles holds great significance in astrobiology. The current review summarizes the diversity of microorganisms inhabiting challenging environments and the biotechnological and therapeutic applications of the active metabolites obtained as a response to stress conditions. Bioprospection of extremophiles provides a progressive direction with significant enhancement in economy. Moreover, the introduction to omics approach including whole genome sequencing, single cell genomics, proteomics, metagenomics etc., has made it possible to find many unique microbial communities that could be otherwise difficult to cultivate using traditional methods. These findings might be capable enough to state that discovery of extremophiles can bring evolution to biotechnology.
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Affiliation(s)
- Manvi Rawat
- Department of Biotechnology, Graphic Era (Deemed to be University), Dehradun, Uttarakhand, 248002, India
| | - Mansi Chauhan
- Department of Microbiology, Graphic Era (Deemed to be University), Dehradun, Uttarakhand, 248002, India
| | - Anita Pandey
- Department of Biotechnology, Graphic Era (Deemed to be University), Dehradun, Uttarakhand, 248002, India.
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2
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Liu Y, Yuan H, Zhu N, Yuan Z. Effect of thermal hydrolysis pretreatment on the stabilization of sludge with different solid contents during autothermal thermophilic aerobic digestion. ENVIRONMENTAL RESEARCH 2023:116347. [PMID: 37290618 DOI: 10.1016/j.envres.2023.116347] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 06/04/2023] [Accepted: 06/06/2023] [Indexed: 06/10/2023]
Abstract
Sludge stabilization was affected by solid content during autothermal thermophilic aerobic digestion (ATAD). Thermal hydrolysis pretreatment (THP) could alleviate the issues of high viscosity, slow solubilization and low ATAD efficiency caused by increased solid content. The influence of THP on the stabilization of sludge with different solid contents (5.24%-17.14%) during ATAD was investigated in this study. The results demonstrated that stabilization was achieved with volatile solid (VS) removal of 39.0%-40.4% after 7-9 days of ATAD for sludge with solid content of 5.24%-17.14%. The solubilization of sludge with different solid contents reached 40.1%-45.0% after THP. The rheological analysis indicated that the apparent viscosity of sludge was obviously reduced after THP at different solid contents. The increase in fluorescence intensity of fulvic acid-like organics, soluble microbial by-products and humic acid-like organics in the supernatant after THP and the decrease in fluorescence intensity of soluble microbial by-products after ATAD were detected by excitation emission matrix (EEM). The molecular weight (MW) distribution in the supernatant elucidated that the proportion of 50 kDa < MW < 100 kDa increased to 16%-34% after THP and the proportion of 10 kDa < MW < 50 kDa decreased to 8%-24% after ATAD. High throughput sequencing showed that the dominant bacterial genera shifted from Acinetobacter, Defluviicoccus and Norank_f__norank_o__PeM15 to Sphaerobacter and Bacillus during ATAD. This work revealed that solid content of 13%-17% was appropriate for efficient ATAD and rapid stabilization under THP.
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Affiliation(s)
- Yangyang Liu
- Shanghai Engineering Research Center of Solid Waste Treatment and Recovery, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Haiping Yuan
- Shanghai Engineering Research Center of Solid Waste Treatment and Recovery, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China.
| | - Nanwen Zhu
- Shanghai Engineering Research Center of Solid Waste Treatment and Recovery, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China.
| | - Zhihang Yuan
- Shanghai Engineering Research Center of Solid Waste Treatment and Recovery, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
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Liu Y, Yuan H, Zhu N. Accelerated stabilization of high solid sludge by thermal hydrolysis pretreatment in autothermal thermophilic aerobic digestion (ATAD) process. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 318:115615. [PMID: 35772274 DOI: 10.1016/j.jenvman.2022.115615] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 06/05/2022] [Accepted: 06/20/2022] [Indexed: 06/15/2023]
Abstract
Autothermal thermophilic aerobic digestion (ATAD) is a rapid biological treatment technology for sludge stabilization. To improve digestion efficiency and shorten stabilization time, thermal hydrolysis pretreatment was employed before ATAD of high solid sludge. The results showed that accelerated stabilization of high solid sludge (total solid = 10.1%) was achieved by thermal hydrolysis pretreatment with volatile solid removal efficiency of 40.3% after 8 days of ATAD, 11 days earlier than unpretreated sludge. The enhanced release and hydrolysis of intracellular organics resulted in a solubilization degree of 45.3%. The reduced sludge viscosity and improved fluidity after thermal hydrolysis facilitated mixing, aeration and organics degradation during ATAD. Excitation emission matrix analysis indicated that the fluorescence intensity of soluble microbial byproduct and tyrosine-like protein increased markedly after thermal hydrolysis and decreased after ATAD. The proportion of high molecular weight (MW > 10 kDa) substances in the supernatant increased significantly after thermal hydrolysis, while the low MW (MW < 1 kDa) substances decreased after ATAD. The significant difference in microbial composition between the pretreatment and control groups elucidated the accelerated sludge stabilization under thermal hydrolysis. This work provides an efficient and practical strategy to achieve rapid stabilization of high solid sludge.
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Affiliation(s)
- Yangyang Liu
- Shanghai Engineering Research Center of Solid Waste Treatment and Resource Recovery, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Haiping Yuan
- Shanghai Engineering Research Center of Solid Waste Treatment and Resource Recovery, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China.
| | - Nanwen Zhu
- Shanghai Engineering Research Center of Solid Waste Treatment and Resource Recovery, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China.
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Zhang M, Tashiro Y, Ishida N, Sakai K. Application of autothermal thermophilic aerobic digestion as a sustainable recycling process of organic liquid waste: Recent advances and prospects. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 828:154187. [PMID: 35240167 DOI: 10.1016/j.scitotenv.2022.154187] [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: 10/29/2021] [Revised: 02/23/2022] [Accepted: 02/23/2022] [Indexed: 06/14/2023]
Abstract
Autothermal thermophilic aerobic digestion (ATAD) has been used to stabilize organic waste since the 1960s and is considered sustainable technology. ATAD has several advantages, including high biodegradation efficiency, pathogen inactivation, and ease of operation. Although ATAD research has a long history, the number of studies on ATAD is much lower than those on similar aerobic processes, particularly composting. Previous review articles addressed the origin, design, operational experiences, metabolism, and the microorganisms at the thermophilic stage of ATAD. This article reviews the digestion systems, applications, and characteristics of ATAD; compares system performance and microbial community structure of ATAD with those of other biological processes such as composting, activated sludge, and anaerobic digestion; and discusses the physicochemical properties and factors of ATAD. The challenges, opportunities, and prospects for the application of ATAD are also discussed. This review suggests that ATAD is feasible for treating organic liquid waste (1-6% total solid content) in small-sized towns and can help establish a sustainable society.
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Affiliation(s)
- Min Zhang
- Laboratory of Soil and Environmental Microbiology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School of Bioresources and Bioenvironmental Sciences, Kyushu University, Fukuoka 819-0395, Japan
| | - Yukihiro Tashiro
- Laboratory of Soil and Environmental Microbiology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School of Bioresources and Bioenvironmental Sciences, Kyushu University, Fukuoka 819-0395, Japan; Laboratory of Microbial Environmental Protection, Tropical Microbiology Unit, Center for International Education and Research of Agriculture, Faculty of Agriculture, Kyushu University, Fukuoka 819-0395, Japan.
| | - Natsumi Ishida
- Laboratory of Soil and Environmental Microbiology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School of Bioresources and Bioenvironmental Sciences, Kyushu University, Fukuoka 819-0395, Japan
| | - Kenji Sakai
- Laboratory of Soil and Environmental Microbiology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School of Bioresources and Bioenvironmental Sciences, Kyushu University, Fukuoka 819-0395, Japan; Laboratory of Microbial Environmental Protection, Tropical Microbiology Unit, Center for International Education and Research of Agriculture, Faculty of Agriculture, Kyushu University, Fukuoka 819-0395, Japan
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Wang Z, Zheng M, Duan H, Ni G, Yu W, Liu Y, Yuan Z, Hu S. Acidic aerobic digestion of anaerobically-digested sludge enabled by a novel ammonia-oxidizing bacterium. WATER RESEARCH 2021; 194:116962. [PMID: 33657493 DOI: 10.1016/j.watres.2021.116962] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 02/05/2021] [Accepted: 02/21/2021] [Indexed: 06/12/2023]
Abstract
Anaerobic digestion is a commonly used process for the reduction and stabilization of wasted activated sludge generated in wastewater treatment plants. However, anaerobically-digested (AD) sludge is still a problematic waste stream due to its large volume and often poor quality. In this study, two aerobic digesters were set up to treat anaerobically-digested sludge, with one digester operated in self-generated acidic condition as the experimental reactor, and one at neutral pH as the control reactor. The acidic condition in the experimental reactor was driven by an inoculated special ammonia-oxidizing bacterium, 'Candidatus Nitrosoglobus', which can tolerate low pH. As a result of ammonium oxidation by Ca. Nitrosoglobus, the pH decreased to 4.8 ± 0.2 and nitrite accumulated to and stayed at 200.0 ± 17.2 mg N L-1, from which free nitrous acid (FNA) at 8.5 ± 1.8 mg HNO2N L-1 formed in-situ. As a combined effect of low pH and high concentration of FNA, the experimental reactor reduced the total solids (TS), volatile solids (VS) and non-volatile solids (NVS) in the AD sludge by 25.2 ± 7.0%, 29.8 ± 4.3%, and 22.6 ± 5.5%, respectively. In contrast, the control reactor without Ca. Nitrosoglobus inoculation (operated at a near-neutral pH of 6.8 ± 0.3 and no FNA formation) only reduced VS in the AD sludge by 10.4 ± 4.3%, along with negligible NVS reduction. Additionally, the acidic aerobic digestion in the experimental reactor significantly stabilized AD sludge, decreasing the specific oxygen uptake rate (SOUR) to 0.5 ± 0.1 mg O2 g-1VS h-1 and the most probable number (MPN) of Faecal Coliforms to 2.4 ± 0.1 log(MPN g-1TS), both of which meet USEPA standards for Class A biosolids. In comparison, the control reactor produced biosolids at Class B level only, with an SOUR of 1.8 ± 0.2 mg O2 g-1VS h-1 and a Faecal Coliforms MPN of 3.6 ± 0.1 log(MPN g-1TS). By reducing the volume and improving the quality of the AD sludge, the acidic aerobic digestion of AD sludge enabled by Ca. Nitrosoglobus has the potential to significantly save the sludge disposal costs in wastewater treatment.
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Affiliation(s)
- Zhiyao Wang
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Min Zheng
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia.
| | - Haoran Duan
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Gaofeng Ni
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Wenbo Yu
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia; School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China
| | - Yanchen Liu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Zhiguo Yuan
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Shihu Hu
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia.
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Iron-assisted biological wastewater treatment: Synergistic effect between iron and microbes. Biotechnol Adv 2020; 44:107610. [DOI: 10.1016/j.biotechadv.2020.107610] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 08/06/2020] [Accepted: 08/08/2020] [Indexed: 12/21/2022]
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Pembroke JT, Ryan MP. Autothermal Thermophilic Aerobic Digestion (ATAD) for Heat, Gas, and Production of a Class A Biosolids with Fertilizer Potential. Microorganisms 2019; 7:E215. [PMID: 31349557 PMCID: PMC6722850 DOI: 10.3390/microorganisms7080215] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 07/22/2019] [Accepted: 07/23/2019] [Indexed: 11/17/2022] Open
Abstract
Autothermal thermophilic aerobic digestion (ATAD) is a microbial fermentation process characterized as a tertiary treatment of waste material carried out in jacketed reactors. The process can be carried out on a variety of waste sludge ranging from human, animal, food, or pharmaceutical waste where the addition of air initiates aerobic digestion of the secondary treated sludge material. Digestion of the sludge substrates generates heat, which is retained within the reactor resulting in elevation of the reactor temperature to 70-75 °C. During the process, deamination of proteinaceous materials also occurs resulting in liberation of ammonia and elevation of pH to typically pH 8.4. These conditions result in a unique microbial consortium, which undergoes considerable dynamic change during the heat-up and holding phases. The change in pH and substrate as digestion occurs also contributes to this dynamic change. Because the large reactors are not optimized for aeration, and because low oxygen solubility at elevated temperatures occurs, there are considerable numbers of anaerobes recovered which also contributes to the overall digestion. As the reactors are operated in a semi-continuous mode, the reactors are rarely washed, resulting in considerable biofilm formation. Equally, because of the fibrous nature of the sludge, fiber adhering organisms are frequently found which play a major role in the overall digestion process. Here, we review molecular tools needed to examine the ATAD sludge consortia, what has been determined through phylogenetic analysis of the consortia and the nature of the dynamics occurring within this unique fermentation environment.
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Affiliation(s)
- J Tony Pembroke
- Department of Chemical Sciences, School of Natural Sciences and Bernal Institute, University of Limerick, V94 T9PX Limerick, Ireland
| | - Michael P Ryan
- Department of Chemical Sciences, School of Natural Sciences and Bernal Institute, University of Limerick, V94 T9PX Limerick, Ireland.
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8
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Duan H, Ye L, Lu X, Batstone DJ, Yuan Z. Self-Sustained Nitrite Accumulation at Low pH Greatly Enhances Volatile Solids Destruction and Nitrogen Removal in Aerobic Sludge Digestion. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:1225-1234. [PMID: 30582696 DOI: 10.1021/acs.est.8b04498] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Aerobic sludge digestion of waste activated sludge (WAS) is widely used as a stabilization option in small- and midsized wastewater treatment plants. However, the digestion process is often limited by low volatile solids (VS) destruction and poor pathogen removal efficiency. This study presents a novel operational strategy that achieves enhanced VS destruction and nitrogen removal by inducing sustained nitrite accumulation via a single spike of nitrite to aerobic digester operated at a natively low pH (<5.5). The strategy was demonstrated through the use of three laboratory aerobic sludge digesters, each continuously operated for over 300 days. Compared to control reactors, the strategy enhanced volatile solids destruction by 35.0-38.4%, nitrogen removal by 58.5-70.8%, and pathogen reduction by approximately 1 log. The standard oxygen uptake rate (SOUR) was reduced to 0.49 ± 0.03 mgO2/gVS/h, compared to 0.85 ± 0.01-1.68 ± 0.02 mgO2/gVS/h in the control, indicating enhanced stabilization. Free nitrous acid formed from nitrite at low pH, rather than nitrite itself, was identified to be the cause of improved digestion performance. Since the nitrite production is self-supporting, no additional ongoing costs are incurred.
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Affiliation(s)
- Haoran Duan
- Advanced Water Management Centre , The University of Queensland , St. Lucia , Queensland 4072 , Australia
| | - Liu Ye
- School of Chemical Engineering , The University of Queensland , St. Lucia , Brisbane , Queensland 4072 , Australia
| | - Xuanyu Lu
- Advanced Water Management Centre , The University of Queensland , St. Lucia , Queensland 4072 , Australia
- School of Chemical Engineering , The University of Queensland , St. Lucia , Brisbane , Queensland 4072 , Australia
| | - Damien J Batstone
- Advanced Water Management Centre , The University of Queensland , St. Lucia , Queensland 4072 , Australia
| | - Zhiguo Yuan
- Advanced Water Management Centre , The University of Queensland , St. Lucia , Queensland 4072 , Australia
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9
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Cheng H, Asakura Y, Kanda K, Fukui R, Kawano Y, Okugawa Y, Tashiro Y, Sakai K. Dynamic bacterial community changes in the autothermal thermophilic aerobic digestion process with cell lysis activities, shaking and temperature increase. J Biosci Bioeng 2018; 126:196-204. [DOI: 10.1016/j.jbiosc.2018.02.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2017] [Revised: 02/16/2018] [Accepted: 02/18/2018] [Indexed: 10/17/2022]
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10
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Tashiro Y, Kanda K, Asakura Y, Kii T, Cheng H, Poudel P, Okugawa Y, Tashiro K, Sakai K. A Unique Autothermal Thermophilic Aerobic Digestion Process Showing a Dynamic Transition of Physicochemical and Bacterial Characteristics from the Mesophilic to the Thermophilic Phase. Appl Environ Microbiol 2018; 84:e02537-17. [PMID: 29305505 PMCID: PMC5835747 DOI: 10.1128/aem.02537-17] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Accepted: 12/20/2017] [Indexed: 01/01/2023] Open
Abstract
A unique autothermal thermophilic aerobic digestion (ATAD) process has been used to convert human excreta to liquid fertilizer in Japan. This study investigated the changes in physicochemical and bacterial community characteristics during the full-scale ATAD process operated for approximately 3 weeks in 2 different years. After initiating simultaneous aeration and mixing using an air-inducing circulator (aerator), the temperature autothermally increased rapidly in the first 1 to 2 days with exhaustive oxygen consumption, leading to a drastic decrease and gradual increase in oxidation-reduction potential in the first 2 days, reached >50°C in the middle 4 to 6 days, and remained steady in the final phase. Volatile fatty acids were rapidly consumed and diminished in the first 2 days, whereas the ammonia nitrogen concentration was relatively stable during the process, despite a gradual pH increase to 9.3. Principal-coordinate analysis of 16S rRNA gene amplicons using next-generation sequencing divided the bacterial community structures into distinct clusters corresponding to three phases, and they were similar in the final phase in both years despite different transitions in the middle phase. The predominant phyla (closest species, dominancy) in the initial, middle, and final phases were Proteobacteria (Arcobacter trophiarum, 19 to 43%; Acinetobacter towneri, 6.3 to 30%), Bacteroidetes (Moheibacter sediminis, 43 to 54%), and Firmicutes (Thermaerobacter composti, 11 to 28%; Heliorestis baculata, 2.1 to 16%), respectively. Two predominant operational taxonomic units (OTUs) in the final phase showed very low similarities to the closest species, indicating that the process is unique compared with previously published ones. This unique process with three distinctive phases would be caused by the aerator with complete aeration.IMPORTANCE Although the autothermal thermophilic aerobic digestion (ATAD) process has several advantages, such as a high degradation capacity, a short treatment period, and inactivation of pathogens, one of the factors limiting its broad application is the high electric power consumption for aerators with a full-scale bioreactor. We elucidated the dynamics of the bacterial community structures, as well as the physicochemical characteristics, in the ATAD process with a full-scale bioreactor from human excreta for 3 weeks. Our results indicated that this unique process can be divided into three distinguishable phases by an aerator with complete aeration and showed a possibility of shortening the digestion period to approximately 10 days. This research not only helps to identify which bacteria play significant roles and how the process can be improved and controlled but also demonstrates an efficient ATAD process with less electric power consumption for worldwide application.
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Affiliation(s)
- Yukihiro Tashiro
- Laboratory of Soil and Environmental Microbiology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School of Bioresources and Bioenvironmental Sciences, Kyushu University, Fukuoka, Japan
- Laboratory of Microbial Environmental Protection, Tropical Microbiology Unit, Center for International Education and Research of Agriculture, Faculty of Agriculture, Kyushu University, Fukuoka, Japan
| | - Kosuke Kanda
- Laboratory of Soil and Environmental Microbiology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School of Bioresources and Bioenvironmental Sciences, Kyushu University, Fukuoka, Japan
| | - Yuya Asakura
- Laboratory of Soil and Environmental Microbiology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School of Bioresources and Bioenvironmental Sciences, Kyushu University, Fukuoka, Japan
| | - Toshihiko Kii
- Laboratory of Soil and Environmental Microbiology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School of Bioresources and Bioenvironmental Sciences, Kyushu University, Fukuoka, Japan
| | - Huijun Cheng
- Laboratory of Soil and Environmental Microbiology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School of Bioresources and Bioenvironmental Sciences, Kyushu University, Fukuoka, Japan
| | - Pramod Poudel
- Laboratory of Soil and Environmental Microbiology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School of Bioresources and Bioenvironmental Sciences, Kyushu University, Fukuoka, Japan
| | - Yuki Okugawa
- Laboratory of Soil and Environmental Microbiology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School of Bioresources and Bioenvironmental Sciences, Kyushu University, Fukuoka, Japan
| | - Kosuke Tashiro
- Laboratory of Molecular Gene Technology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, Fukuoka, Japan
| | - Kenji Sakai
- Laboratory of Soil and Environmental Microbiology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School of Bioresources and Bioenvironmental Sciences, Kyushu University, Fukuoka, Japan
- Laboratory of Microbial Environmental Protection, Tropical Microbiology Unit, Center for International Education and Research of Agriculture, Faculty of Agriculture, Kyushu University, Fukuoka, Japan
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Liu W, Peng Y, Ma B, Ma L, Jia F, Li X. Dynamics of microbial activities and community structures in activated sludge under aerobic starvation. BIORESOURCE TECHNOLOGY 2017; 244:588-596. [PMID: 28803110 DOI: 10.1016/j.biortech.2017.07.131] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 07/21/2017] [Accepted: 07/23/2017] [Indexed: 06/07/2023]
Abstract
The knowledge of the effect of aerobic starvation on the functional bacterial activities and community structures is important for the recovery of nutrient removal in activated sludge system. Four aerobic starvation processes (3, 7, 14 and 30days) for nitrifiers and polyphosphate accumulating organisms (PAOs) were studied. The results showed that nitrifiers could utilize the released ammonium for growth during the first 7days of the aerobic starvation, and then gradually decayed. In the recovery period, the slower recovery ability of nitrite-oxidizing bacteria (NOB) than ammonium-oxidizing bacteria (AOB) contributed to the nitrite accumulation. Besides, the sequential consumption of polyhydroxyalkanoates (PHA), glycogen and the utilization of polyphosphate (poly-P) in PAOs provided the energy to maintain bacterial metabolic activity. High-throughput sequencing analysis revealed that aerobic starvation had substantial impacts on the succession of microbial community, and the majority of original dominant species within the phylum Proteobacteria and Bacteroidetes declined while Firmicutes increased.
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Affiliation(s)
- Wenlong Liu
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Yongzhen Peng
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China; Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China.
| | - Bin Ma
- Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China
| | - Linna Ma
- Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China
| | - Fangxu Jia
- Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China
| | - Xiyao Li
- Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China
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12
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Qin W, Fan F, Zhu Y, Huang X, Ding A, Liu X, Dou J. Anaerobic biodegradation of benzo(a)pyrene by a novel Cellulosimicrobium cellulans CWS2 isolated from polycyclic aromatic hydrocarbon-contaminated soil. Braz J Microbiol 2017; 49:258-268. [PMID: 29102294 PMCID: PMC5913828 DOI: 10.1016/j.bjm.2017.04.014] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 03/23/2017] [Accepted: 04/25/2017] [Indexed: 12/14/2022] Open
Abstract
Cellulosimicrobium cellulans CWS2, a novel strain capable of utilizing benzo(a)pyrene (BaP) as the sole carbon and energy source under nitrate-reducing conditions, was isolated from PAH-contaminated soil. Temperature and pH significantly affected BaP biodegradation, and the strain exhibited enhanced biodegradation ability at temperatures above 30 °C and between pH 7 and 10. The highest BaP removal rate (78.8%) was observed in 13 days when the initial BaP concentration was 10 mg/L, and the strain degraded BaP at constant rate even at a higher concentration (50 mg/L). Metal exposure experimental results illustrated that Cd(II) was the only metal ion that significantly inhibited biodegradation of BaP. The addition of 0.5 and 1.0 g/L glucose enhanced BaP biodegradation, while the addition of low-molecular-weight organic acids with stronger acidity reduced BaP removal rates during co-metabolic biodegradation. The addition of phenanthrene and pyrene, which were degraded to some extent by the strain, showed no distinct effect on BaP biodegradation. Gas chromatography–mass spectrometry (GC-MS) analysis revealed that the five rings of BaP opened, producing compounds with one to four rings which were more bioavailable. Thus, the strain exhibited strong BaP degradation capability and has great potential in the remediation of BaP-/PAH-contaminated environments.
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Affiliation(s)
- Wei Qin
- Beijing Normal University, College of Water Sciences, Beijing, China
| | - Fuqiang Fan
- Memorial University of Newfoundland, Faculty of Engineering and Applied Science, Northern Region Persistent Organic Pollution Control Laboratory, St. John's, Canada
| | - Yi Zhu
- Beijing Normal University, College of Water Sciences, Beijing, China
| | - Xiaolong Huang
- Beijing Normal University, College of Water Sciences, Beijing, China
| | - Aizhong Ding
- Beijing Normal University, College of Water Sciences, Beijing, China
| | - Xiang Liu
- Tsinghua University, School of Environment, Beijing, China
| | - Junfeng Dou
- Beijing Normal University, College of Water Sciences, Beijing, China.
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Jin N, Shou Z, Yuan H, Lou Z, Zhu N. Selective simplification and reinforcement of microbial community in autothermal thermophilic aerobic digestion to enhancing stabilization process of sewage sludge by conditioning with ferric nitrate. BIORESOURCE TECHNOLOGY 2016; 204:106-113. [PMID: 26773954 DOI: 10.1016/j.biortech.2016.01.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Revised: 12/31/2015] [Accepted: 01/05/2016] [Indexed: 06/05/2023]
Abstract
The effect of ferric nitrate on microbial community and enhancement of stabilization process for sewage sludge was investigated in autothermal thermophilic aerobic digestion. The disinhibition of volatile fatty acids (VFA) was obtained with alteration of individual VFA concentration order. Bacterial taxonomic identification by 454 high-throughput pyrosequencing found the dominant phylum Proteobacteria in non-dosing group was converted to phylum Firmicutes in dosing group after ferric nitrate added and simplification of bacteria phylotypes was achieved. The preponderant Tepidiphilus sp. vanished, and Symbiobacterium sp. and Tepidimicrobium sp. were the most advantageous phylotypes with conditioning of ferric nitrate. Consequently, biodegradable substances in dissolved organic matters increased, which contributed to the favorable environment for microbial metabolism and resulted in acceleration of sludge stabilization. Ultimately, higher stabilization level was achieved as ratio of soluble chemical oxygen demand to total chemical oxygen demand (TCOD) decreased while TCOD reduced as well in dosing group comparing to non-dosing group.
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Affiliation(s)
- Ningben Jin
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Zongqi Shou
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Haiping Yuan
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Ziyang Lou
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Nanwen Zhu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
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14
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Garg KK, Prasad B. Treatment of multicomponent aqueous solution of purified terephthalic acid wastewater by electrocoagulation process: Optimization of process and analysis of sludge. J Taiwan Inst Chem Eng 2016. [DOI: 10.1016/j.jtice.2015.10.038] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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15
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Jang HM, Ha JH, Park JM, Kim MS, Sommer SG. Comprehensive microbial analysis of combined mesophilic anaerobic-thermophilic aerobic process treating high-strength food wastewater. WATER RESEARCH 2015; 73:291-303. [PMID: 25689817 DOI: 10.1016/j.watres.2015.01.038] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 01/27/2015] [Accepted: 01/28/2015] [Indexed: 06/04/2023]
Abstract
A combined mesophilic anaerobic-thermophilic aerobic process was used to treat high-strength food wastewater in this study. During the experimental period, most of solid residue from the mesophilic anaerobic reactor (R1) was separated by centrifugation and introduced into the thermophilic aerobic reactor (R2) for further digestion. Then, thermophilic aerobically-digested sludge was reintroduced into R1 to enhance reactor performance. The combined process was operated with two different Runs: Run I with hydraulic retention time (HRT) = 40 d (corresponding OLR = 3.5 kg COD/m(3) d) and Run II with HRT = 20 d (corresponding OLR = 7 kg COD/m(3)). For a comparison, a single-stage mesophilic anaerobic reactor (R3) was operated concurrently with same OLRs and HRTs as the combined process. During the overall digestion, all reactors showed high stability without pH control. The combined process demonstrated significantly higher organic matter removal efficiencies (over 90%) of TS, VS and COD and methane production than did R3. Quantitative real-time PCR (qPCR) results indicated that higher populations of both bacteria and archaea were maintained in R1 than in R3. Pyrosequencing analysis revealed relatively high abundance of phylum Actinobacteria in both R1 and R2, and a predominance of phyla Synergistetes and Firmicutes in R3 during Run II. Furthermore, R1 and R2 shared genera (Prevotella, Aminobacterium, Geobacillus and Unclassified Actinobacteria), which suggests synergy between mesophilic anaerobic digestion and thermophilic aerobic digestion. For archaea, in R1 methanogenic archaea shifted from genus Methanosaeta to Methanosarcina, whereas genera Methanosaeta, Methanobacterium and Methanoculleus were predominant in R3. The results demonstrated dynamics of key microbial populations that were highly consistent with an enhanced reactor performance of the combined process.
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Affiliation(s)
- Hyun Min Jang
- School of Environmental Science and Engineering, Pohang University of Science and Technology, 77, Cheongam-Ro, Pohang 790-784, Republic of Korea
| | - Jeong Hyub Ha
- School of Environmental Science and Engineering, Pohang University of Science and Technology, 77, Cheongam-Ro, Pohang 790-784, Republic of Korea; Department of Chemical Engineering, Pohang University of Science and Technology, 77, Cheongam-Ro, Pohang 790-784, Republic of Korea.
| | - Jong Moon Park
- School of Environmental Science and Engineering, Pohang University of Science and Technology, 77, Cheongam-Ro, Pohang 790-784, Republic of Korea; Department of Chemical Engineering, Pohang University of Science and Technology, 77, Cheongam-Ro, Pohang 790-784, Republic of Korea; Division of Advanced Nuclear Engineering, Pohang University of Science and Technology, 77, Cheongam-Ro, Pohang 790-784, Republic of Korea.
| | - Mi-Sun Kim
- Biomass and Waste Energy Laboratory, Korea Institute of Energy Research, 152 Gajeong-ro, Yuseong-gu, Daejeon 305-343, Republic of Korea
| | - Sven G Sommer
- Institute of Chemical Engineering, Biotechnology and Environmental Technology, Faculty of Engineering, University of Southern Denmark, Niels Bohrs Allé 1, DK-5230 Odense M, Denmark
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16
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Zhang Q, Shuwen G, Zhang J, Fane AG, Kjelleberg S, Rice SA, McDougald D. Analysis of microbial community composition in a lab-scale membrane distillation bioreactor. J Appl Microbiol 2015; 118:940-53. [PMID: 25604265 PMCID: PMC4409088 DOI: 10.1111/jam.12759] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Revised: 01/01/2015] [Accepted: 01/11/2015] [Indexed: 12/23/2022]
Abstract
Aims Membrane distillation bioreactors (MDBR) have potential for industrial applications where wastewater is hot or waste heat is available, but the role of micro-organisms in MDBRs has never been determined, and thus was the purpose of this study. Methods and Results Microbial communities were characterized by bacterial and archaeal 16S and eukaryotic 18S rRNA gene tag-encoded pyrosequencing of DNA obtained from sludge. Taxonomy-independent analysis revealed that bacterial communities had a relatively low richness and diversity, and community composition strongly correlated with conductivity, total nitrogen and bound extracellular polymeric substances (EPS). Taxonomy-dependent analysis revealed that Rubrobacter and Caldalkalibacillus were abundant members of the bacterial community, but no archaea were detected. Eukaryotic communities had a relatively high richness and diversity, and both changes in community composition and abundance of the dominant genus, Candida, correlated with bound EPS. Conclusions Thermophilic MDBR communities were comprised of a low diversity bacterial community and a highly diverse eukaryotic community with no archea detected. Communities exhibited low resilience to changes in operational parameters. Specifically, retenatate nutrient composition and concentration was strongly correlated with the dominant species. Significance and Impact of the Study This study provides an understanding of microbial community diversity in an MDBR, which is fundamental to the optimization of reactor performance.
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Affiliation(s)
- Q Zhang
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, Singapore City, Singapore; School of Biological Sciences, Nanyang Technological University, Singapore City, Singapore
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17
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Jin N, Shou Z, Yuan H, Lou Z, Zhu N. Effects of ferric nitrate additions under different pH conditions on autothermal thermophilic aerobic digestion for sewage sludge. RSC Adv 2015. [DOI: 10.1039/c5ra16761b] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Effects of ferric nitrate additions under different pH conditions on disinhibition of excessive VFAs for enhancement of ATAD performance.
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Affiliation(s)
- Ningben Jin
- School of Environmental Science and Engineering
- Shanghai Jiao Tong University
- Shanghai 200240
- China
| | - Zongqi Shou
- School of Environmental Science and Engineering
- Shanghai Jiao Tong University
- Shanghai 200240
- China
| | - Haiping Yuan
- School of Environmental Science and Engineering
- Shanghai Jiao Tong University
- Shanghai 200240
- China
| | - Ziyang Lou
- School of Environmental Science and Engineering
- Shanghai Jiao Tong University
- Shanghai 200240
- China
| | - Nanwen Zhu
- School of Environmental Science and Engineering
- Shanghai Jiao Tong University
- Shanghai 200240
- China
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18
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Li XK, Ma KL, Meng LW, Zhang J, Wang K. Performance and microbial community profiles in an anaerobic reactor treating with simulated PTA wastewater: from mesophilic to thermophilic temperature. WATER RESEARCH 2014; 61:57-66. [PMID: 24952270 DOI: 10.1016/j.watres.2014.04.033] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Revised: 04/15/2014] [Accepted: 04/18/2014] [Indexed: 06/03/2023]
Abstract
Performance and microbial community profiles in a hybrid anaerobic reactor treating synthetic PTA wastewater (contained the major pollutants terephthalate and benzoate) were studied over 220 days from 33 °C to 52 °C. Results indicated that PTA treatment process was highly sensitive to temperature variations in terms of COD removal. Operation at 37 °C showed the best performance as well as the most diverse microbial community revealed by 16S rRNA gene clone library and T-RFLP (terminal restriction fragment length polymorphism). Finally, the anaerobic process achieved a total COD removal of 77.4%, 91.9%, 87.4% and 66.1% at 33, 37, 43 and 52 °C. While the corresponding TA removal were 77.6%, 94.0%, 89.1% and 60.8%, respectively. Sequence analyses revealed acetoclastic Methanosaeta was preponderant at 37 °C, while hydrogenotrophic genera including Methanobrevibacter and Methanofollis were more abundant at other temperatures. For bacterial community, 16 classes were identified. The largely existent Syntrophorhabdus members (belonging to δ-Proteobacteria) at 37 °C was likely to play an important role in mesophilic anaerobic wastewater treatment system contained terephthalate. Meanwhile, β-Proteobacteria seemed to be favored in an anaerobic system higher than 43 °C.
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Affiliation(s)
- Xiang-kun Li
- School of Municipal and Environmental Engineering, State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 73 Huanghe Road, Harbin 150090, China.
| | - Kai-li Ma
- School of Municipal and Environmental Engineering, State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 73 Huanghe Road, Harbin 150090, China
| | - Ling-wei Meng
- School of Municipal and Environmental Engineering, State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 73 Huanghe Road, Harbin 150090, China
| | - Jie Zhang
- School of Municipal and Environmental Engineering, State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 73 Huanghe Road, Harbin 150090, China
| | - Ke Wang
- School of Municipal and Environmental Engineering, State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 73 Huanghe Road, Harbin 150090, China.
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19
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Baek G, Kim J, Lee C. Influence of ferric oxyhydroxide addition on biomethanation of waste activated sludge in a continuous reactor. BIORESOURCE TECHNOLOGY 2014; 166:596-601. [PMID: 24929299 DOI: 10.1016/j.biortech.2014.05.052] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Revised: 05/15/2014] [Accepted: 05/16/2014] [Indexed: 06/03/2023]
Abstract
This study investigated the potential of enhancing the activity of iron-reducing bacteria (IRBs) to increase the biomethanation rate of waste activate sludge (WAS). The effects of biostimulation by ferric oxyhydroxide (Phase 2) and bioaugmentation with an enriched IRB consortium (Phase 3) were examined in a continuous anaerobic reactor treating WAS. Compared to the control operation (Phase 1), significant rises in methane yield (10.8-59.4%) and production rate (24.5-52.9%) were demonstrated by the biostimulation and bioaugmentation treatments. Visible structural changes were observed in bacterial community with the phases while not in archaeal community. Acinetobacter- and Spirochaetales-related populations were likely the major players driving anaerobic iron respiration and thus leading to enhanced biomethanation performance, in Phases 2 and 3, respectively. Our results suggest an interesting new potential for enhancing biomethanation of WAS.
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Affiliation(s)
- Gahyun Baek
- School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan 689-798, Republic of Korea
| | - Jaai Kim
- School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan 689-798, Republic of Korea
| | - Changsoo Lee
- School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan 689-798, Republic of Korea.
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20
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Jang HM, Cho HU, Park SK, Ha JH, Park JM. Influence of thermophilic aerobic digestion as a sludge pre-treatment and solids retention time of mesophilic anaerobic digestion on the methane production, sludge digestion and microbial communities in a sequential digestion process. WATER RESEARCH 2014; 48:1-14. [PMID: 23871253 DOI: 10.1016/j.watres.2013.06.041] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Revised: 06/15/2013] [Accepted: 06/20/2013] [Indexed: 05/16/2023]
Abstract
In this study, the changes in sludge reduction, methane production and microbial community structures in a process involving two-stage thermophilic aerobic digestion (TAD) and mesophilic anaerobic digestion (MAD) under different solid retention times (SRTs) between 10 and 40 days were investigated. The TAD reactor (RTAD) was operated with a 1-day SRT and the MAD reactor (RMAD) was operated at three different SRTs: 39, 19 and 9 days. For a comparison, control MAD (RCONTROL) was operated at three different SRTs of 40, 20 and 10 days. Our results reveal that the sequential TAD-MAD process has about 42% higher methane production rate (MPR) and 15% higher TCOD removal than those of RCONTROL when the SRT decreased from 40 to 20 days. Denaturing gradient gel electrophoresis (DGGE) and real-time PCR results indicate that RMAD maintained a more diverse bacteria and archaea population compared to RCONTROL, due to the application of the biological TAD pre-treatment process. In RTAD, Ureibacillus thermophiles and Bacterium thermus were the major contributors to the increase in soluble organic matter. In contrast, Methanosaeta concilii, a strictly aceticlastic methanogen, showed the highest population during the operation of overall SRTs in RMAD. Interestingly, as the SRT decreased to 20 days, syntrophic VFA oxidizing bacteria, Clostridium ultunense sp., and a hydrogenotrophic methanogen, Methanobacterium beijingense were detected in RMAD and RCONTROL. Meanwhile, the proportion of archaea to total microbe in RMAD and RCONTROL shows highest values of 10.5 and 6.5% at 20-d SRT operation, respectively. Collectively, these results demonstrate that the increased COD removal and methane production at different SRTs in RMAD might be attributed to the increased synergism among microbial species by improving the hydrolysis of the rate limiting step in sludge with the help of the biological TAD pre-treatment.
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Affiliation(s)
- Hyun Min Jang
- School of Environmental Science and Engineering, San 31, Hyoja-dong, Pohang 790-784, South Korea
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21
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Wang Z, Yu H, Ma J, Zheng X, Wu Z. Recent advances in membrane bio-technologies for sludge reduction and treatment. Biotechnol Adv 2013; 31:1187-99. [DOI: 10.1016/j.biotechadv.2013.02.004] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Revised: 02/20/2013] [Accepted: 02/23/2013] [Indexed: 10/27/2022]
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22
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Piterina AV, Pembroke JT. Use of PCR-DGGE Based Molecular Methods to Analyse Microbial Community Diversity and Stability during the Thermophilic Stages of an ATAD Wastewater Sludge Treatment Process as an Aid to Performance Monitoring. ISRN BIOTECHNOLOGY 2013; 2013:162645. [PMID: 25937969 PMCID: PMC4393042 DOI: 10.5402/2013/162645] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Accepted: 08/20/2013] [Indexed: 01/07/2023]
Abstract
PCR and PCR-DGGE techniques have been evaluated to monitor biodiversity indexes within an ATAD (autothermal thermophilic aerobic digestion) system treating domestic sludge for land spread, by examining microbial dynamics in response to elevated temperatures during treatment. The ATAD process utilises a thermophilic population to generate heat and operates at elevated pH due to degradation of sludge solids, thus allowing pasteurisation and stabilisation of the sludge. Genera-specific PCR revealed that Archaea, Eukarya and Fungi decline when the temperature reaches 59°C, while the bacterial lineage constitutes the dominant group at this stage. The bacterial community at the thermophilic stage, its similarity index to the feed material, and the species richness present were evaluated by PCR-DGGE. Parameters such as choice of molecular target (16S rDNA or rpoB genes), and electrophoresis condition, were optimised to maximise the resolution of the method for ATAD. Dynamic analysis of microbial communities was best observed utilising PCR-DGGE analysis of the V6-V8 region of 16S rDNA, while rpoB gene profiles were less informative. Unique thermophilic communities were shown to quickly adapt to process changes, and shown to be quite stable during the process. Such techniques may be used as a monitoring technique for process health and efficiency.
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Affiliation(s)
- Anna V Piterina
- Department of Chemical and Environmental Sciences and the Material and Surface Science Institute (MSSI), University of Limerick, Limerick, Ireland
| | - J Tony Pembroke
- Department of Chemical and Environmental Sciences and the Material and Surface Science Institute (MSSI), University of Limerick, Limerick, Ireland
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23
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Combined mesophilic anaerobic and thermophilic aerobic digestion process: effect on sludge degradation and variation of sludge property. Appl Biochem Biotechnol 2013; 171:1701-14. [PMID: 23996119 DOI: 10.1007/s12010-013-0453-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Accepted: 08/20/2013] [Indexed: 10/26/2022]
Abstract
One-stage autothermal thermophilic aerobic digestion (ATAD) is effective for the reduction of volatile solids (VSs) and pathogen in sewage sludges. A novel process of combining mesophilic (<35 °C) anaerobic digestion with a thermophilic (55 °C) aerobic digestion process (AN/TAD) occurred in a one-stage digester, which was designed for aeration energy savings. The efficiency of sludge degradation and variation of sludge properties by batch experiments were evaluated for the AN/TAD digester with an effective volume of 23 L for 30 days compared with conventional thermophilic aerobic digestion (TAD). The AN/TAD system can efficiently achieve sludge stabilization on the 16th day with a VS removal rate of 38.1 %. The AN/TAD system was operated at lower ORP values in a digestion period with higher contents of total organic compounds, volatile fatty acids, protein, and polysaccharide in the soluble phase than those of the TAD system, which can rapidly decreased and had low values in the late period of digestion for the AN/TAD system. In the AN/TAD system, intracellular substances had lysis because of initial hydrolytic acidification.
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