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Gao Z, Zhang Z, Li Q, Wu H, Wang M, Tian X, Wang A, Li J. Improving contaminant removal and inhibiting CH 4 and H 2S emissions from septic tanks: Nitrified human urine as a source of electron acceptor. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 951:175410. [PMID: 39127217 DOI: 10.1016/j.scitotenv.2024.175410] [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: 05/11/2024] [Revised: 08/06/2024] [Accepted: 08/07/2024] [Indexed: 08/12/2024]
Abstract
Septic tanks are widely adopted in decentralized household wastewater treatment systems serving billions of people globally. Due to the lack of effective electron acceptors, insufficient nutrient removal and the emission of harmful gases, e. g. H2S, CH4, etc., are the common drawbacks. In the present work, we attempted to supplement nitrite into septic tanks as an electron acceptor, via nitrifying human urine source-separated from blackwater, to overcome these drawbacks. Partial or complete nitritation of source-separated urine was achieved in a sequencing batch reactor. The addition of nitrified urine into septic tanks improved organic and nitrogen removals in blackwater up to 90 % and 70 %, respectively. The emission of harmful gases from the septic tanks was stably diminished, with more than 75 % of CH4, CO2 and H2S reductions. Nitrite addition significantly reduced the abundance of hydrogenotrophic methanogens in septic tanks. Though the activity of sulfate-reducing bacteria recovered after the initial inhibition upon nitrite addition, the bio-generated H2S was retained in water since the increased wastewater pH after nitrite addition promoted the disassociation of H2S in aqueous solution.
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Affiliation(s)
- Zhenchao Gao
- School of Environment, Beijing Jiaotong University, Beijing 100044, China
| | - Zhongguo Zhang
- School of Environment, Beijing Jiaotong University, Beijing 100044, China; Institute of Resources and Environment, Beijing Academy of Science and Technology, Beijing 100089, China.
| | - Qingyun Li
- China Academy of Space Technology, Beijing 100081, China
| | - Haoyuan Wu
- School of Environment, Beijing Jiaotong University, Beijing 100044, China
| | - Mengyu Wang
- School of Environment, Beijing Jiaotong University, Beijing 100044, China
| | - Xiujun Tian
- School of Environment, Beijing Jiaotong University, Beijing 100044, China
| | - Aimin Wang
- School of Environment, Beijing Jiaotong University, Beijing 100044, China
| | - Jiuyi Li
- School of Environment, Beijing Jiaotong University, Beijing 100044, China.
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Li Z, Dou Y, Li Z, Yuan Y, Zhang Q, Cheng S, Cheng X, Luo J. Dose-dependent effects of different parabens on food waste biorefinery for volatile fatty acids production: Insight into specific fermentation processes, substrates transformation and microbial metabolic traits. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 946:174319. [PMID: 38936728 DOI: 10.1016/j.scitotenv.2024.174319] [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: 04/02/2024] [Revised: 06/23/2024] [Accepted: 06/24/2024] [Indexed: 06/29/2024]
Abstract
Parabens are largely concentrated in food waste (FW) due to their large consumption as the widely used preservative. To date, whether and how they affect FW resource recovery via anaerobic fermentation is still largely unknown. This work unveiled the hormesis-like effects of two typical parabens (i.e., methylparaben and n-butylparaben) on VFAs production during FW anaerobic fermentation (i.e., parabens increased VFAs by 6.73-14.49 % at low dose but caused 82.51-87.74 % reduction at high dose). Mechanistic exploration revealed that the parabens facilitated the FW solubilization and enhanced the associated substrates' biodegradability. The low parabens enriched the functional microorganisms (e.g., Firmicutes and Actinobacteria) and upregulated those critical genes involved in VFAs biosynthesis (e.g., GCK and PK) by activating the microbial adaptive capacity (i.e., quorum sensing and two-component system). Consequently, the metabolism rates of fermentation substrates and subsequent VFAs production were accelerated. However, due to increased biotoxicity of high parabens, the functional microorganisms and relevant metabolic activities were depressed, resulting in the significant reduction of VFAs biosynthesis. Structural equation modeling clarified that microbial community was the predominant factor affecting VFAs generation, followed by metabolic pathways. This work elucidated the dose-dependent effects and underlying mechanisms of parabens on FW anaerobic fermentation, providing insights for the effective management of FW resource recovery.
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Affiliation(s)
- Ziyu Li
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Yuting Dou
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Zhenzhou Li
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Yujie Yuan
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Qin Zhang
- School of Energy and Environment, Anhui University of Technology, Ma'anshan 243000, China
| | - Song Cheng
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Xiaoshi Cheng
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China.
| | - Jingyang Luo
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China.
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Shi K, Xu JM, Cui HL, Cheng HY, Liang B, Wang AJ. Microbiome regulation for sustainable wastewater treatment. Biotechnol Adv 2024:108458. [PMID: 39343082 DOI: 10.1016/j.biotechadv.2024.108458] [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: 05/26/2024] [Revised: 08/30/2024] [Accepted: 09/26/2024] [Indexed: 10/01/2024]
Abstract
Sustainable wastewater treatment is imperative for attaining clean water and sanitation, aligning with a UN Sustainable Development Goal. Wastewater treatment plants (WWTPs) have utilized environmental microbiomes in biological treatment processes in this effort for over a century. However, the inherent complexity and redundancy of microbial communities, and emerging chemical and biological contaminants, challenge the biotechnology applications. Over the past decades, understanding and utilization of microbial energy metabolism and interaction relationships have revolutionized the biological system. In this review, we discuss how microbiome regulation strategies are being used to generate actionable performance for low-carbon pollutant removal and resource recovery in WWTPs. The engineering application cases also highlight the real feasibility and promising prospects of the microbiome regulation approaches. In conclusion, we advocate for the identification of environmental risks associated with chemical and biological contaminants transformation as a prerequisite. We propose the integration of gene editing and enzyme design to precisely regulate microbiomes for the synergistic control of both chemical and biological risks. Additionally, the development of integrated technologies and engineering equipment is imperative in addressing the ongoing water crisis. This review advocates for the innovation of conventional wastewater treatment biotechnology to ensure sustainable wastewater treatment.
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Affiliation(s)
- Ke Shi
- State Key Laboratory of Urban Water Resource and Environment, School of Civil & Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, China
| | - Jia-Min Xu
- State Key Laboratory of Urban Water Resource and Environment, School of Civil & Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, China
| | - Han-Lin Cui
- State Key Laboratory of Urban Water Resource and Environment, School of Civil & Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, China
| | - Hao-Yi Cheng
- State Key Laboratory of Urban Water Resource and Environment, School of Civil & Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, China
| | - Bin Liang
- State Key Laboratory of Urban Water Resource and Environment, School of Civil & Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, China.
| | - Ai-Jie Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Civil & Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, China.
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Wu H, Bai X, Li L, Li Z, Wang M, Zhang Z, Zhu C, Xu Y, Xiong H, Xie X, Tian X, Li J. Two-stage partial nitrification-denitrification and anammox process for nitrogen removal in vacuum collected toilet wastewater at ambient temperature. ENVIRONMENTAL RESEARCH 2024; 262:119917. [PMID: 39251178 DOI: 10.1016/j.envres.2024.119917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2024] [Revised: 08/21/2024] [Accepted: 09/01/2024] [Indexed: 09/11/2024]
Abstract
Vacuum collected toilet wastewater (VCTW) contains high and fluctuating contents of organics and nitrogen, which exerts technological challenges to biological treatment processes. A partial nitrification-denitrification and anammox (PND-AMX) process was developed in sequencing batch reactor (SBR) and moving bed biofilm reactor (MBBR) to achieve effective nitrogen removal in VCTW at low ambient temperature. Stable PND was achieved, and nitrogen removal efficiency in SBR could be manipulated by adjusting influent COD/N ratios. As temperature ≥18 °C, 91.0% nitrogen was removed in PND-AMX process. In spite of the decreased anammox activity at 13-18 °C, more than 90% nitrogen removal could be obtained by adjusting SBR influent COD/N to 2.43 ± 0.32 with methanol. In MBBR reactor, Candidatus Kuenenia was the dominant anammox bacteria and contributed to more than 90% nitrogen removal capacity. Co-existing anammox and denitrifying bacteria synergistically contributed to the removal of ammonium, nitrite, nitrate, and COD in MBBR.
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Affiliation(s)
- Haoyuan Wu
- School of Environment, Beijing Jiaotong University, Beijing, 100044, China
| | - Xiaolei Bai
- School of Environment, Beijing Jiaotong University, Beijing, 100044, China
| | - Lei Li
- Beijing Key Laboratory of Watershed Water Environment and Ecological Technology, Beijing Water Science and Technology Institute, Beijing, 100048, China
| | - Zhaoxin Li
- Beijing Key Laboratory of Watershed Water Environment and Ecological Technology, Beijing Water Science and Technology Institute, Beijing, 100048, China
| | - Mengyu Wang
- School of Environment, Beijing Jiaotong University, Beijing, 100044, China
| | - Zhongguo Zhang
- School of Environment, Beijing Jiaotong University, Beijing, 100044, China; Institute of Resources and Environment, Beijing Academy of Science and Technology, Beijing, 100089, China
| | - Cheng Zhu
- School of Environment, Beijing Jiaotong University, Beijing, 100044, China; Tianheshui Environmental Technology Co., Ltd., Nanjing, 210017, China
| | - Yuanmin Xu
- School of Environment, Beijing Jiaotong University, Beijing, 100044, China; Tianheshui Environmental Technology Co., Ltd., Nanjing, 210017, China
| | - Huiqin Xiong
- Nanjing Jianye District Water Bureau, Nanjing, 210017, China
| | - Xin Xie
- Nanjing Jianye District Water Facilities Comprehensive Maintenance Center, Nanjing, 210017, China
| | - Xiujun Tian
- School of Environment, Beijing Jiaotong University, Beijing, 100044, China
| | - Jiuyi Li
- School of Environment, Beijing Jiaotong University, Beijing, 100044, China.
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5
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Shi K, Liang B, Cheng HY, Wang HC, Liu WZ, Li ZL, Han JL, Gao SH, Wang AJ. Regulating microbial redox reactions towards enhanced removal of refractory organic nitrogen from wastewater. WATER RESEARCH 2024; 258:121778. [PMID: 38795549 DOI: 10.1016/j.watres.2024.121778] [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: 12/11/2023] [Revised: 05/10/2024] [Accepted: 05/12/2024] [Indexed: 05/28/2024]
Abstract
Biotechnology for wastewater treatment is mainstream and effective depending upon microbial redox reactions to eliminate diverse contaminants and ensure aquatic ecological health. However, refractory organic nitrogen compounds (RONCs, e.g., nitro-, azo-, amide-, and N-heterocyclic compounds) with complex structures and high toxicity inhibit microbial metabolic activity and limit the transformation of organic nitrogen to inorganic nitrogen. This will eventually result in non-compliance with nitrogen discharge standards. Numerous efforts suggested that applying exogenous electron donors or acceptors, such as solid electrodes (electrostimulation) and limited oxygen (micro-aeration), could potentially regulate microbial redox reactions and catabolic pathways, and facilitate the biotransformation of RONCs. This review provides comprehensive insights into the microbial regulation mechanisms and applications of electrostimulation and micro-aeration strategies to accelerate the biotransformation of RONCs to organic amine (amination) and inorganic ammonia (ammonification), respectively. Furthermore, a promising approach involving in-situ hybrid anaerobic biological units, coupled with electrostimulation and micro-aeration, is proposed towards engineering applications. Finally, employing cutting-edge methods including multi-omics analysis, data science driven machine learning, technology-economic analysis, and life-cycle assessment would contribute to optimizing the process design and engineering implementation. This review offers a fundamental understanding and inspiration for novel research in the enhanced biotechnology towards RONCs elimination.
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Affiliation(s)
- Ke Shi
- State Key Laboratory of Urban Water Resource and Environment, School of Civil & Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, China
| | - Bin Liang
- State Key Laboratory of Urban Water Resource and Environment, School of Civil & Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, China.
| | - Hao-Yi Cheng
- State Key Laboratory of Urban Water Resource and Environment, School of Civil & Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, China
| | - Hong-Cheng Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Civil & Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, China
| | - Wen-Zong Liu
- State Key Laboratory of Urban Water Resource and Environment, School of Civil & Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, China
| | - Zhi-Ling Li
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Jing-Long Han
- State Key Laboratory of Urban Water Resource and Environment, School of Civil & Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, China
| | - Shu-Hong Gao
- State Key Laboratory of Urban Water Resource and Environment, School of Civil & Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, China
| | - Ai-Jie Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Civil & Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen 518055, China.
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6
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Liu K, Lv L, Li W, Wang X, Han M, Ren Z, Gao W, Wang P, Liu X, Sun L, Zhang G. Micro-aeration and leachate recirculation for the acceleration of landfill stabilization: Enhanced hydrolytic acidification by facultative bacteria. BIORESOURCE TECHNOLOGY 2023; 387:129615. [PMID: 37544542 DOI: 10.1016/j.biortech.2023.129615] [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: 06/14/2023] [Revised: 07/26/2023] [Accepted: 08/01/2023] [Indexed: 08/08/2023]
Abstract
The long duration of landfill stabilization is one of the challenges faced by municipalities. In this paper, a combination of micro-aeration and leachate recirculation is used to achieve rapid degradation of organic matter in landfill waste. The results showed that the content of volatile fatty acids (VFAs) in the hydrolysis phase increased significantly and could enter the methanogenic phase quickly. Until the end of the landfill, the removal rates of chemical oxygen demand (COD), total phosphorus (TP) and ammonia nitrogen (NH4+-N) by micro-aeration and leachate recirculation reached 80.17 %, 48.30 % and 48.56 %, respectively, and the organic matter degradation rate reached 50 %. Micro-aeration and leachate recirculation enhanced the abundance of facultative hydrolytic bacteria such as Rummeliibacillus and Bacillus and the oxygen tolerance of Methanobrevibacter and Methanoculleus. Micro-aeration and leachate recirculation improved the organic matter degradation efficiency of landfill waste by promoting the growth of functional microorganisms.
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Affiliation(s)
- Kaili Liu
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Longyi Lv
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China.
| | - Weiguang Li
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), Harbin 150090, PR China
| | - Xinyuan Wang
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Muda Han
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Zhijun Ren
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Wenfang Gao
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Pengfei Wang
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Xiaoyang Liu
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Li Sun
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Guangming Zhang
- Tianjin Key Laboratory of Clean Energy and Pollution Control, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China.
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7
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Huiliñir C, Pagés-Díaz J, Vargas G, Vega S, Lauzurique Y, Palominos N. Microaerobic condition as pretreatment for improving anaerobic digestion: A review. BIORESOURCE TECHNOLOGY 2023:129249. [PMID: 37268090 DOI: 10.1016/j.biortech.2023.129249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 05/24/2023] [Accepted: 05/26/2023] [Indexed: 06/04/2023]
Abstract
Pretreatment of waste before anaerobic digestion (AD) has been extensively studied during the last decades. One of the biological pretreatments studied is the microaeration. This review examines this process, including parameters and applications to different substrates at the lab, pilot and industrial scales, to guide further improvement in large-scale applications. The underlying mechanisms of accelerating hydrolysis and its effects on microbial diversity and enzymatic production were reviewed. In addition, modelling of the process and energetic and financial analysis is presented, showing that microaerobic pretreatment is commercially attractive under certain conditions. Finally, challenges and future perspectives were also highlighted to promote the development of microaeration as a pretreatment before AD.
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Affiliation(s)
- César Huiliñir
- Laboratorio de Biotecnología Ambiental, Departamento de Ingeniería Química y Bioprocesos, Universidad de Santiago de Chile, Av. Lib. Bdo. O Higgins 3363, Santiago de Chile, Chile.
| | - Jhosané Pagés-Díaz
- Laboratorio de Biotecnología Ambiental, Departamento de Ingeniería Química y Bioprocesos, Universidad de Santiago de Chile, Av. Lib. Bdo. O Higgins 3363, Santiago de Chile, Chile
| | - Gustavo Vargas
- Laboratorio de Biotecnología Ambiental, Departamento de Ingeniería Química y Bioprocesos, Universidad de Santiago de Chile, Av. Lib. Bdo. O Higgins 3363, Santiago de Chile, Chile
| | - Sylvana Vega
- Laboratorio de Biotecnología Ambiental, Departamento de Ingeniería Química y Bioprocesos, Universidad de Santiago de Chile, Av. Lib. Bdo. O Higgins 3363, Santiago de Chile, Chile
| | - Yeney Lauzurique
- Laboratorio de Biotecnología Ambiental, Departamento de Ingeniería Química y Bioprocesos, Universidad de Santiago de Chile, Av. Lib. Bdo. O Higgins 3363, Santiago de Chile, Chile
| | - Nicolás Palominos
- Laboratorio de Biotecnología Ambiental, Departamento de Ingeniería Química y Bioprocesos, Universidad de Santiago de Chile, Av. Lib. Bdo. O Higgins 3363, Santiago de Chile, Chile
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Zhang G, Wang G, Zhou Y, Zhu DZ, Zhang Y, Zhang T. Simultaneous use of nitrate and calcium peroxide to control sulfide and greenhouse gas emission in sewers. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 855:158913. [PMID: 36411604 DOI: 10.1016/j.scitotenv.2022.158913] [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: 07/01/2022] [Revised: 08/24/2022] [Accepted: 09/17/2022] [Indexed: 06/16/2023]
Abstract
The sewer system is a significant source of hydrogen sulfide (H2S) and greenhouse gases which has attracted extensive interest from researchers. In this study, a novel combined dosing strategy using nitrate and calcium peroxide (CaO2) was proposed to simultaneously control sulfide and greenhouse gases, and its performance was evaluated in laboratory-scale reactors. Results suggested that the addition of nitrate and CaO2 improved the effectiveness of sulfide control. And the combination index method further proved that nitrate and CaO2 were synergistic in controlling sulfide. Meanwhile, the combination of nitrate and CaO2 substantially reduced greenhouse gas emissions, especially the carbon dioxide (CO2) and methane (CH4). The microbial analysis revealed that the combined addition greatly stimulated the accumulation of nitrate reducing-sulfide oxidizing bacteria (NR-SOB) that participate in anoxic nitrate-dependent sulfide oxidation, while the abundance of heterotrophic denitrification bacteria (hNRB) was reduced significantly. Moreover, the presence of oxygen and alkaline chemicals generated by CaO2 facilitated the inhibition of sulfate-reducing bacteria (SRB) activities. Therefore, the nitrate dosage was diminished significantly. On the other hand, the generated alkaline chemicals promoted CO2 elimination and inhibited the activities of methanogens, leading to a decrease of CO2 and CH4 fluxes, which facilitated elimination of greenhouse effects. The intermittent dosing test showed that the nitrate and CaO2 could be applied intermittently for sulfide removal. And the chemical cost of intermittent dosing strategy was reduced by 85 % compared to the continuous dosing nitrate strategy. Therefore, intermittent dosing nitrate combined with CaO2 is probably an effective and economical approach to control sulfide and greenhouse gases in sewer systems.
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Affiliation(s)
- Guijiao Zhang
- College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058, China
| | - Gaowu Wang
- Hangzhou Binjiang water Co., Ltd, Hangzhou 310058, China
| | - Yongchao Zhou
- College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058, China.
| | - David Z Zhu
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB T6G 2W2, Canada; School of Civil and Environmental Engineering, Ningbo University, Zhejiang, 315211, China
| | - Yiping Zhang
- College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058, China
| | - Tuqiao Zhang
- College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058, China
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9
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Cao Q, Zhang W, Lian T, Wang S, Yin F, Zhou T, Wei X, Dong H. Revealing mechanism of micro-aeration for enhancing volatile fatty acids production from swine manure. BIORESOURCE TECHNOLOGY 2022; 365:128140. [PMID: 36252761 DOI: 10.1016/j.biortech.2022.128140] [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: 08/06/2022] [Revised: 10/10/2022] [Accepted: 10/11/2022] [Indexed: 06/16/2023]
Abstract
Micro-aeration is considered a new strategy for improving volatile fatty acids (VFAs) production of agricultural waste. This study investigated the effect and mechanism of micro-aeration of air and oxygen (O2) on VFAs production from swine manure. The results showed that Air-micro-aeration had the most significant improvement effect, with the highest VFAs of 8.21 g/L, which was increased by 22.4%. Moreover, the mixing effects of different micro-aeration were limited, and the microbial communities significantly varied. Firmicutes and Bacteroidota were the dominant hydrolytic and acidogenic bacteria, and Air-micro-aeration preferentially promoted electron transfer activity and energy generation. Methanosarcina, Methanocorpusculum, and Methanobrevibacter can adapt to environmental changes according to their different oxygen tolerance, and the consumption and conversion of VFAs by methanogens were slow under Air-micro-aeration condition. This study revealed mechanism of micro-aeration for improving VFAs production from swine manure, providing a theoretical basis for micro-aeration regulation optimization.
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Affiliation(s)
- Qitao Cao
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Wanqin Zhang
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Tianjing Lian
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China; College of Natural Resources and Environment, Northwest A&F University, Yangling 712100, PR China
| | - Shunli Wang
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Fubin Yin
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Tanlong Zhou
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Xiaoman Wei
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Hongmin Dong
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China.
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10
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Mou A, Yu N, Sun H, Liu Y. Spatial distributions of granular activated carbon in up-flow anaerobic sludge blanket reactors influence methane production treating low and high solid-content wastewater. BIORESOURCE TECHNOLOGY 2022; 363:127995. [PMID: 36150426 DOI: 10.1016/j.biortech.2022.127995] [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: 08/24/2022] [Revised: 09/14/2022] [Accepted: 09/15/2022] [Indexed: 06/16/2023]
Abstract
The impacts of granular activated carbon (GAC) spatial distributions in up-flow anaerobic sludge blanket (UASB) reactors treating different solid-content wastewater were evaluated in the present study. When treating high solid-content wastewater, the highest methane yield was observed for UASB supplemented with self-floating GAC (74.2 ± 3.7 %), which was followed by settled + self-floating GAC reactor (65.1 ± 3.8 %), then settled GAC reactor (58.3 ± 1.4 %). When treating low solid-content wastewater, all UASBs achieved improved methane yield, and settled + self-floating GAC reactor achieved the highest methane yield (83.4 ± 3.3 %). Self-floating GAC amended reactor showed the best performance for treating high solid-content wastewater, while settled + self-floating GAC amended reactor was optimal for treating medium and low solid-content wastewater. The spatial distributions of microbial communities differed in the reactors with settled GAC and floating GAC. This study underlines the importance of considering feedwater characteristics when adopting GAC-based UASB processes.
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Affiliation(s)
- Anqi Mou
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Najiaowa Yu
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Huijuan Sun
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Yang Liu
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada; School of Civil & Environmental Engineering, Queensland University of Technology, Brisbane, Queensland, Australia.
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Yu N, Mou A, Sun H, Liu Y. Anaerobic digestion of thickened waste activated sludge under calcium hypochlorite stress: Performance stability and microbial communities. ENVIRONMENTAL RESEARCH 2022; 212:113441. [PMID: 35561820 DOI: 10.1016/j.envres.2022.113441] [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: 03/16/2022] [Revised: 04/30/2022] [Accepted: 05/04/2022] [Indexed: 06/15/2023]
Abstract
Hypochlorite pretreatment has been proven effective in enhancing waste activated sludge (WAS) anaerobic digestion performances recently. In this study, two semi-continuous anaerobic sequencing batch reactors (ASBRs), one fed with Ca(ClO)2 pretreated thickened WAS (TWAS) and one with raw TWAS, were operated at mesophilic conditions (35 °C) for 145 days. Three loading shocks were introduced to each reactor to compare the performance stability and resilience between the digestion of Ca(ClO)2 pretreated TWAS and untreated TWAS. Microbial community shifts were quantified to reveal the microbiome responses to disturbances. The results suggested that 1% Ca(ClO)2 enhanced the digestion of TWAS by inactivating and transforming the biomass to more easily digested substrates. Co-occurrence network analysis revealed that the strongest interactions in the microbial community occurred in the steady state of TWAS anaerobic digestion.
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Affiliation(s)
- Najiaowa Yu
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB, T6G 1H9, Canada
| | - Anqi Mou
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB, T6G 1H9, Canada
| | - Huijuan Sun
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB, T6G 1H9, Canada
| | - Yang Liu
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB, T6G 1H9, Canada
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12
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Li W, Liu Y, Wu B, Gu L, Deng R. Upgrade the high-load anaerobic digestion and relieve acid stress through the strategy of side-stream micro-aeration: biochemical performances, microbial response and intrinsic mechanisms. WATER RESEARCH 2022; 221:118850. [PMID: 35949076 DOI: 10.1016/j.watres.2022.118850] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Revised: 07/03/2022] [Accepted: 07/09/2022] [Indexed: 06/15/2023]
Abstract
In high-load anaerobic digestion such as in kitchen waste, side-stream micro-aeration (SMA) shows excellent operational performance to direct micro-aeration (DMA). It immediately restores the acidification to stability. Methanogenic performance remained stable when organic load ratios (OLR) was further increased to 5.5 g VS/L. Enhanced enzyme activity, microbial aggregation, and proliferation of bacteria and archaea were observed in SMA. The results indicates that SMA enriched Methanosaeta (relative abundance exceeded 93%) and induced the change of the main methanogenic pathway to acetoclastic methanogenesis. Mechanisms was further explored by using metagenomic analysis, and the results show SMA avoids mass formation of ROS (reactive oxygen species) by cycling the aerated slurry, and retains benefits of trace O2 on material and energic metabolism, which poses great application potentials and deserves further investigation.
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Affiliation(s)
- Wen Li
- Key laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Yongli Liu
- Key laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Baocun Wu
- Key laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China
| | - Li Gu
- Key laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, 174 Shapingba Road, Chongqing 400045, PR China.
| | - Rui Deng
- School of Architecture and Urban Planning, Chongqing Jiaotong University, Chongqing 400074, PR China
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13
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Li X, Zhao X, Zhang J, Hao J, Zhang Q. Struvite crystallization by using active serpentine: An innovative application for the economical and efficient recovery of phosphorus from black water. WATER RESEARCH 2022; 221:118678. [PMID: 35752092 DOI: 10.1016/j.watres.2022.118678] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 03/29/2022] [Accepted: 05/25/2022] [Indexed: 06/15/2023]
Abstract
Recovery of phosphorus from wastewater through struvite crystallization is one of the most attractive methods. However, the cost of chemical consumption makes this technology is unattractive to some extent. In this work, highly active serpentine was prepared by one-step mechanical activation and then used to recover phosphate as struvite from the black water containing 132.8 mg/L phosphorus and 3144 mg/L ammonia nitrogen. The results indicated that the prepared active serpentine can release magnesium ions and hydroxide ions simultaneously into an aqueous solution and is an ideal raw material for struvite crystallization. The factors for phosphorus recovery in this process mainly include mechanical activation intensity, serpentine dosage, and contact time. For the actual black water, a high recovery rate of phosphorus (>98%) is achieved by using active serpentine as the magnesium and alkali source for struvite precipitation. The recovery product was identified as struvite with a median particle size of 32.96 μm. It was confirmed that the mechanical activation damaged the crystal structure of the raw serpentine, improving the activity of Mg2+ and OH-. The undissolved Si-containing particles act as crystal seeds, accelerating the struvite crystallization process. Furthermore, a pilot-scale test was conducted with a rural public toilet in Xiong'an New District, Hebei Province. The results showed that an acceptable phosphorus recovery (98%) could be achieved using active serpentine. Additionally, it was demonstrated that the serpentine process to recover phosphate as struvite reduced the cost by 54.4% in compared with an ordinary chemical process. The active serpentine is a promising dual source of magnesium and alkali for the phosphorus recovery by the struvite method. It has a potential prospect for the large-scale application in phosphorus recovery and struvite fertilizer production.
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Affiliation(s)
- Xuewei Li
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China; Ganjiang Innovation Academy, Chinese Academy of Sciences, Ganzhou 341119, PR China
| | - Xu Zhao
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China.
| | - Juanjuan Zhang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China
| | - Jingwei Hao
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China
| | - Qiwu Zhang
- School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan 430070, PR China
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14
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Pan W, Ouyang H, Tan X, Deng R, Gu L, He Q. Anaerobic dynamic membrane bioreactors for synthetic blackwater treatment under room temperature and mesophilic conditions. BIORESOURCE TECHNOLOGY 2022; 355:127295. [PMID: 35550923 DOI: 10.1016/j.biortech.2022.127295] [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: 03/23/2022] [Revised: 05/05/2022] [Accepted: 05/06/2022] [Indexed: 06/15/2023]
Abstract
Two anaerobic dynamic membrane bioreactors (AnDMBRs) were set up for the treatment of synthetic blackwater at room temperature (20-25 °C) and mesophilic conditions for 180 days with progressively increased organic loading rates(OLR). Despite dynamic membranes (DM), organics removal at room temperature was similar to removal within the mesophilic conditions of the reactor, with some disparities in methane production. A dense sludge filtration layer was more likely to be formed on the DM at room temperature, resulting in a faster membrane fouling. Microbial community analysis revealed that microorganisms had higher richness and lower diversity at room temperature, which was beneficial to the growth of Actinobacteriota, especially Propioniciclava. This comparative study discusses the feasibility of operating an AnDMBR under room temperature conditions versus mesophilic conditions. This analysis provides novel insights into future large-scale attempts to treat blackwater at room temperature.
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Affiliation(s)
- Weiliang Pan
- School of River and Ocean Engineering, Chongqing Jiaotong University, Chongqing 400074, PR China.
| | - Honglin Ouyang
- School of River and Ocean Engineering, Chongqing Jiaotong University, Chongqing 400074, PR China
| | - Xiuqing Tan
- School of River and Ocean Engineering, Chongqing Jiaotong University, Chongqing 400074, PR China
| | - Rui Deng
- School of Architecture and Urban Planning, Chongqing Jiaotong University, Chongqing 400074, PR China
| | - Li Gu
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, Chongqing 400045, PR China
| | - Qiang He
- Key Laboratory of the Three Gorges Reservoir Region's Eco-environments, Ministry of Education, Institute of Environment and Ecology, Chongqing University, Chongqing 400045, PR China
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15
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Intermittent Microaeration Technology to Enhance the Carbon Source Release of Particulate Organic Matter in Domestic Sewage. WATER 2022. [DOI: 10.3390/w14121876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
Domestic sewage treatment plants often have insufficient carbon sources in the influent water. To solve this problem, the commonly used technical means include an additional carbon source, primary sludge fermentation, and excess sludge fermentation, but these methods are uneconomical, unsustainable, and not applicable to small-scale wastewater treatment plants. Intermittent microaeration technology has the advantages of low energy-consumption, ease of application, and low cost, and can effectively promote anaerobic digestion of municipal sludge; however little research has been reported on its use to enhance the carbon sources release of particulate organic matter (POM) from domestic wastewater. Therefore, the effect of intermittent microaeration on the carbon source release of POM was evaluated in this study, with POM as the control test. The results showed that the release concentration of soluble chemical oxygen demand (SCOD) was the highest on day 4 under microaerobic conditions, and the concentrations of SCOD, NH4+-N, and PO43−-P in the liquid phase were 1153, 137.1, and 13 mg/L, respectively. Compared with the control group, the SCOD concentration increased by 34.2%, and the NH4+-N and PO43−-P concentrations decreased by 18.65% and 17.09%, respectively. Intermittent microaeration can effectively promote the growth of Paludibacter, Actinomyces, and Trichococcus hydrolytic fermentation functional bacteria. Their relative abundances increased by 282.83%, 21.77%, and 23.47%, respectively, compared with the control group. It can simultaneously inhibit the growth of acetate-type methanogenic archaea, Methanosaeta and Methanosarcina, with a decrease in relative abundances of 16.81% and 6.63%, respectively. The aforementioned data show that intermittent microaeration can not only promote the hydrolysis of POM, but can also reduce the loss of acetic acid carbon source, which is a cost-effective technical way to enhance the release of a carbon source of particulate organic matter in domestic sewage.
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16
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The Measurement, Application and Effect of Oxygen in Microbial Fermentations: Focusing on Methane and Carboxylate Production. FERMENTATION-BASEL 2022. [DOI: 10.3390/fermentation8040138] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Oxygen is considered detrimental to anaerobic fermentation processes by many practitioners. However, deliberate oxygen sparging has been used successfully for decades to remove H2S in anaerobic digestion (AD) systems. Moreover, microaeration techniques during AD have shown that small doses of oxygen may enhance process performance and promote the in situ degradation of recalcitrant compounds. However, existing oxygen dosing techniques are imprecise, which has led to inconsistent results between studies. At the same time, real-time oxygen fluxes cannot be reliably quantified due to the complexity of most bioreactor systems. Thus, there is a pressing need for robust monitoring and process control in applications where oxygen serves as an operating parameter or an experimental variable. This review summarizes and evaluates the available methodologies for oxygen measurement and dosing as they pertain to anaerobic microbiomes. The historical use of (micro-)aeration in anaerobic digestion and its potential role in other anaerobic fermentation processes are critiqued in detail. This critique also provides insights into the effects of oxygen on these microbiomes. Our assessment suggests that oxygen dosing, when implemented in a controlled and quantifiable manner, could serve as an effective tool for bioprocess engineers to further manipulate anaerobic microbiomes for either bioenergy or biochemical production.
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17
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Cao Q, Zhang W, Lian T, Wang S, Yin F, Zhou T, Zhang H, Zhu J, Dong H. Roles of micro-aeration on enhancing volatile fatty acids and lactic acid production from agricultural wastes. BIORESOURCE TECHNOLOGY 2022; 347:126656. [PMID: 34974096 DOI: 10.1016/j.biortech.2021.126656] [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: 11/03/2021] [Revised: 12/26/2021] [Accepted: 12/27/2021] [Indexed: 06/14/2023]
Abstract
Micro-aeration was proven to be an environmentally friendly strategy for efficiently enhancing volatile fatty acids (VFAs) and lactic acid (LA) production. The roles of micro-aeration on mono-digestion of swine manure (SM) for VFAs production and co-digestion of SM with corn silage (CS) for LA production were investigated, respectively. In this study, micro-aeration increased the maximum VFAs concentration by 20.3% to 35.71 g COD/L, and shortened the time to reach the maximum from 18 days to 10 days. Micro-aeration limited the conversion of LA into VFAs, leading to LA accumulation effectively to be 26.08 g COD/L. Microbial community analysis suggested that Clostridium and Terrisporobacter were always the dominant bacteria with or without micro-aeration for VFAs production, but the relative abundance increased notably during the same period. However, Bifidobacterium, which could use the higher productivity metabolism pathway, i.e., Bifidum pathway to produce LA, increased from lower than 1% to 22.9% by micro-aeration.
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Affiliation(s)
- Qitao Cao
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Wanqin Zhang
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Tianjing Lian
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Shunli Wang
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Fubin Yin
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Tanlong Zhou
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Haiyan Zhang
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Jun Zhu
- Department of Biological and Agricultural Engineering, University of Arkansas, Fayetteville, AR 72701, USA
| | - Hongmin Dong
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China.
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18
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Yu N, Sun H, Mou A, Liu Y. Calcium hypochlorite enhances the digestibility of and the phosphorus recovery from waste activated sludge. BIORESOURCE TECHNOLOGY 2021; 340:125658. [PMID: 34332447 DOI: 10.1016/j.biortech.2021.125658] [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: 06/03/2021] [Revised: 07/19/2021] [Accepted: 07/22/2021] [Indexed: 06/13/2023]
Abstract
Waste activated sludge (WAS) can be treated using anaerobic digestion (AD) for biogas recovery and volume reduction. However, the poor digestibility and hydrolysis of WAS limit AD applications. The current study investigated the feasibility of applying calcium hypochlorite as a WAS pretreatment strategy to improve AD treatment efficiency using laboratory reactors. The results showed that pretreatment with 5 - 20% Ca(ClO)2 (total suspended solids basis) significantly enhanced WAS anaerobic digestibility, and led to significantly enhanced methane production rate and biomethane yield comparing to the AD of raw WAS (P < 0.05). Low Ca(ClO)2 pretreatment (5 - 10%) significantly enhanced digestion efficiency, which can be attributed to the development of fermentative and syntrophic bacteria. However, high Ca(ClO)2 doses (>20%) reduced microbial activities, leading to slow release of dissolved organic compounds and prolonged methane production lag phase. In addition, high Ca(ClO)2 removed 82.7% of the initial phosphate by calcium-phosphate binding, reducing the phosphorus in liquid digestate.
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Affiliation(s)
- Najiaowa Yu
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Huijuan Sun
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Anqi Mou
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Yang Liu
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada.
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19
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Yu N, Guo B, Liu Y. Shaping biofilm microbiomes by changing GAC location during wastewater anaerobic digestion. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 780:146488. [PMID: 33774284 DOI: 10.1016/j.scitotenv.2021.146488] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 03/09/2021] [Accepted: 03/11/2021] [Indexed: 06/12/2023]
Abstract
The addition of granular activated carbon (GAC) to up-flow anaerobic sludge blanket (UASB) reactors treating synthetic wastewater enhanced methane production by stimulating direct interspecies electron transfer (DIET). A modified UASB reactor with GAC packed in plastic carriers that allowed the GAC to float in the upper reactor zone achieved enhanced performance compared to a UASB reactor with GAC settled at the bottom of the reactor. Microbial communities in the biofilms developed on settled or floated GAC were compared. Methanosarcina (56.3-73.3%) dominated the floated-GAC biofilm whereas Methanobacterium (84.9-85.1%) was greatly enriched in the settled-GAC biofilm. Methanospirillum and Methanocorpusculum were enriched in the floated-GAC biofilm (8.8-19.8% and 5.1-9.5%, respectively), but only existed in low abundances in the settled-GAC biofilm (3.4-3.6% and 0-0.4%, respectively). The floated GAC developed bacterial communities with higher diversity and more syntrophic bacteria enrichments on its surface, including Geobacter, Smithella, and Syntrophomonas, than the settled-GAC biofilm. Common hydrogen-donating syntrophs and hydrogenotrophic archaea, Methanospirillum and Methanoregula, were identified as potential electro-active microorganisms related to DIET.
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Affiliation(s)
- Najiaowa Yu
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Bing Guo
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Yang Liu
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada.
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20
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Zhang Q, Li R, Guo B, Zhang L, Liu Y. Thermophilic co-digestion of blackwater and organic kitchen waste: Impacts of granular activated carbon and different mixing ratios. WASTE MANAGEMENT (NEW YORK, N.Y.) 2021; 131:453-461. [PMID: 34265699 DOI: 10.1016/j.wasman.2021.06.024] [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: 02/21/2021] [Revised: 05/29/2021] [Accepted: 06/25/2021] [Indexed: 06/13/2023]
Abstract
Biogas (methane) as a source of renewable energy, was produced in the anaerobic co-digestion of blackwater (BW, municipal toilet wastewater) and organic kitchen waste (KW). The impact on methane production of various BW to KW mixing ratios, with and without the addition of granular activated carbon (GAC), were studied under thermophilic (55 °C) temperatures. GAC is reported to enhance methane production in such digestions through direct interspecies electron transfer. The results showed that the co-digestion of BW and KW under the 1:2 VS ratio significantly improved the biomethane potential (BMP). In the absence of GAC, an optimal BW:KW ratio was found to be 1:2, achieving a BMP of 0.76 g CH4-COD/g feed-COD. With GAC addition, the BMP increased to 0.81 g CH4-COD/g feed-COD, the lag phase in the digestion was significantly reduced, and the methane production rate increased. Microbial communities in the BW-KW anaerobic digestion were analyzed with and without the addition of GAC. Methanothermobacter and Methanosarcina were predominant archaea in BW-KW digests, with and without GAC amendment, while a third methanogen, Methanomassiliicoccus, was enriched with the addition of GAC to the digest. Further, through SEM image, the enrichment of pili-like stucture was observed in GAC surface.
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Affiliation(s)
- Qianyi Zhang
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Ran Li
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada; College of Petroleum Engineering, Xi'an Shiyou University, Xi'an 710065, Shaanxi Province, China
| | - Bing Guo
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Lei Zhang
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Yang Liu
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada.
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21
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Guo B, Yu N, Weissbrodt DG, Liu Y. Effects of micro-aeration on microbial niches and antimicrobial resistances in blackwater anaerobic digesters. WATER RESEARCH 2021; 196:117035. [PMID: 33751974 DOI: 10.1016/j.watres.2021.117035] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 03/02/2021] [Accepted: 03/08/2021] [Indexed: 06/12/2023]
Abstract
Anaerobic digestion (AD) of source-diverted blackwater (toilet flush) at ambient room temperature presents challenges for fast hydrolysis of particulate matters. This study investigated the effect of different micro-aeration dosages for blackwater AD. Sequencing batch reactors were operated at ambient room temperature (22 ± 1°C) with micro-aeration (0, 5, 10, 50, and 150 mg O2 g-1 CODfeed per cycle) and gradually reduced hydraulic retention times from 5 d to 2 d. The methanogenesis efficiencies were greater at low oxygen dosages (i.e., 0, 5, 10) while the volatile fatty acids (VFAs) accumulated more at high oxygen dosages (i.e., 50, 150). Microbial communities were significantly different under different oxygen dosages (p<0.05), with segregation of microbial ecological niches in low and high oxygen dosage communities. The low-oxygen-dosage niche (0, 5, and 10 mg g-1 CODfeed) was inhabited by fermenting and syntrophic bacteria (e.g., Cytophaga, Syntrophomonas) and methanogens (e.g., Methanobacterium, Methanolinea, Methanosaeta). The high-oxygen-dosage niche (50 and 150 mg g-1 CODfeed) had significantly (p<0.05) more facultative anaerobic bacteria (Ignavibacteriales and Cloacamonales), and aerobic bacteria (Rhodocyclales). Moreover, blackwater can be a source of antimicrobial resistance genes (ARGs), which are affected by different oxygen dosages. The ARG variation correlated with the microbial community composition (p<0.05). Low-oxygen-dosage communities contained a higher prevalence of mobile gene elements (intI1 and korB) and tetM, ermB, sul1, sul2, and blaCTX-M than the high-oxygen-dosage communities, indicating that oxygen dosage influenced the prevalence of populations carrying ARGs. These findings suggest that application of micro-aeration to AD can be used to control ARG profiles.
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Affiliation(s)
- Bing Guo
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta, T6G 1H9, Canada; Department of Biotechnology, Delft University of Technology, Delft, Netherlands
| | - Najiaowa Yu
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta, T6G 1H9, Canada
| | - David G Weissbrodt
- Department of Biotechnology, Delft University of Technology, Delft, Netherlands
| | - Yang Liu
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta, T6G 1H9, Canada.
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22
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Guo B, Zhang Y, Yu N, Liu Y. Impacts of conductive materials on microbial community during syntrophic propionate oxidization for biomethane recovery. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2021; 93:84-93. [PMID: 32391609 DOI: 10.1002/wer.1357] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Revised: 04/21/2020] [Accepted: 04/26/2020] [Indexed: 06/11/2023]
Abstract
Propionate is one of the most important intermediates in anaerobic digestion, and its degradation requires a syntrophic partnership between propionate-oxidizing bacteria and hydrogenotrophic methanogens. Anaerobic digestion efficiency can be improved by direct interspecies electron transfer (DIET) through conductive materials. This study aimed to investigate the effects of DIET on syntrophic propionate oxidization under room temperature (20°C) and reveal the syntrophic partners. Firstly, conventional anaerobic consortium and conductive material-enriched consortium were tested for DIET under high H2 partial pressure. The latter supplemented with granular activated carbon (GAC) can mitigate H2 inhibition through DIET. Secondly, a DIET consortium was enriched for testing GAC and magnetite, both showed DIET facilitation. Microbial communities in GAC- and magnetite-supplemented reactors were similar. Syntrophic propionate-oxidizing bacteria, for example, Smithella (3.9%-9.9%) and a genus from the family Syntrophaceae (1.9%-3.6%) and methanogens Methanobacterium (30.3%-75.2%), Methanolinea (8.5%-25.2%), Methanosaeta (11.4%-36.7%), and Candidatus Methanofastidiosum (3.6%-6.6%), were predominant. Functional genes for cell mobility and membrane transport (3.3% and 9.5% in control reactor) increased with GAC (3.7% and 11.1%, respectively) and magnetite (3.7% and 10.9%, respectively) addition. Syntrophic propionate-oxidizing bacteria and methanogenesis partners were revealed by co-occurrence network, for example, Methanobacterium with Smithella, Syntrophobacter, Dechloromonas, and Trichococcus, signifying the importance of the syntrophic partnership in DIET environment. PRACTITIONER POINTS: DIET improved syntrophic propionate oxidization under room temperature condition (20°C). Microbial communities were similar for GAC- and magnetite-supplemented reactors, different with control reactor. Syntrophic propionate-oxidizing bacteria and methanogenesis partners were revealed by co-occurrence network. Methanobacterium and Smithella, Syntrophobacter, Dechloromonas, and Trichococcus were correlated.
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Affiliation(s)
- Bing Guo
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB, Canada
| | - Yingdi Zhang
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB, Canada
| | - Najiaowa Yu
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB, Canada
| | - Yang Liu
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB, Canada
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23
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Zhang Y, Guo B, Zhang L, Liu Y. Key syntrophic partnerships identified in a granular activated carbon amended UASB treating municipal sewage under low temperature conditions. BIORESOURCE TECHNOLOGY 2020; 312:123556. [PMID: 32464511 DOI: 10.1016/j.biortech.2020.123556] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 05/16/2020] [Accepted: 05/17/2020] [Indexed: 06/11/2023]
Abstract
Two laboratory-scale up-flow anaerobic sludge blankets (UASB) reactors, one with and one without granular activated carbon (GAC), were operated for municipal sewage treatment at low temperatures (16.5 ± 2.0 °C). During the 120-day operation, the GAC-amended reactor significantly enhanced COD removal (from 62% to 75%, P < 0.05) and methane production (from 87 to 218 mg CH4-COD/reactor/d) than the non-GAC reactor. Bacterial communities were significantly different between the two reactors (P < 0.05). Geobacter, a key indicator for direct interspecies electron transfer (DIET), had the highest differential score (LEfSe analysis), showing significantly higher abundances in the GAC-amended reactor (3.7-8.8%) than the non-GAC reactor (0.9-4.0%). GAC also enriched syntrophic bacteria, Syntrophomonas, Syntrophus and sulfate reducing bacteria. Methanobacterium dominated the archaeal community in the GAC-amended reactor sludge (35.7%) and GAC-biofilm (75.3%), and was less abundant in the non-GAC reactor (9.9%). It indicates that GAC enriched microbial syntrophic partners with potential electro-activities in the anaerobic digestion process.
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Affiliation(s)
- Yingdi Zhang
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Bing Guo
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Lei Zhang
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada
| | - Yang Liu
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada.
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Evaluation of Microaeration and Sound to Increase Biogas Production from Poultry Litter. ENVIRONMENTS 2020. [DOI: 10.3390/environments7080062] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Microaeration, wherein small amounts of air are introduced into otherwise anaerobic digesters, has been shown to enhance biogas production. This occurs by fostering the growth of facultatively aerobic bacteria and production of enzymes that enhance the degradation of complex polymers such as cellulose. The treatment of anaerobic digestate with sound at sonic frequencies (<20 kHz) has also been shown to improve biogas production. Microaeration at a rate of 800 mL day−1, treatment with a 1000-Hz sine wave, and combined microaeration/sound were compared to a control digester for the production of biogas and their effect on wastewater quality. Poultry litter from a facility using wood chips as bedding was used as feed. The initial feeding rate was 400 g week−1, and this was slowly increased to a final rate of 2400 g week−1. Compared to the control, sound treatment, aeration, and combined sound/aeration produced 17%, 32%, and 28% more biogas. The aeration alone treatment may have been more effective than combined aeration/sound due to the sound interfering with retention of aeration or the formation of free radicals during cavitation. Digesters treated with sound had the highest concentrations of suspended solids, likely due to cavitation occurring within the sludge and the resulting suspension of fine particles by bubbles.
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