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Jiang T, Li X, Yang J, Wang L, Wang W, Zhang L, Wang B. Potential of free nitrous acid (FNA) for sludge treatment and resource recovery from waste activated sludge: A review. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 360:121170. [PMID: 38749134 DOI: 10.1016/j.jenvman.2024.121170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 04/18/2024] [Accepted: 05/11/2024] [Indexed: 06/05/2024]
Abstract
The escalating production of waste activated sludge (WAS) presents significant challenges to wastewater treatment plants (WWTPs). Free nitrous acid (FNA), known for its biocidal effect, has gained a growing focus on sludge dewatering, sludge reduction, and resource recovery from WAS due to its eco-friendly and cost-effective properties. Nevertheless, there have been no attempts made to systematically summarize or critically analyze the application of FNA in enhancing treatment and resource utilization of sludge. In this paper, we provided an overview of the current understanding regarding the application potential and influencing factors of FNA in sludge treatment, with a specific focus on enhancing sludge dewatering efficiency and reducing volume. To foster resource development from sludge, various techniques based on FNA have recently been proposed, which were comprehensively reviewed with the corresponding mechanisms meticulously discussed. The results showed that the chemical oxidation and interaction with microorganisms of FNA played the core role in improving resource utilization. Furthermore, current challenges and future prospects of the FNA-based applications were outlined. It is expected that this review can refine the theoretical framework of FNA-based processes, providing a theoretical foundation and technical guidance for the large-scale demonstration of FNA.
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Affiliation(s)
- Tan Jiang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Xiaodi Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Jiayi Yang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Lu Wang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Wen Wang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Li Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Bo Wang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China.
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2
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Okoye F, Kakar FL, Elbeshbishy E. Novel free nitrous acid and ultrasonication pretreatment enhanced sludge biodegradability. ENVIRONMENTAL TECHNOLOGY 2024; 45:1829-1840. [PMID: 36469644 DOI: 10.1080/09593330.2022.2155252] [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: 05/04/2022] [Accepted: 11/28/2022] [Indexed: 06/17/2023]
Abstract
The main goal of this study was to investigate the novel combined Ultrasonication and Free Nitrous Acid (FNA) pretreatment on biodegradability and kinetics of thickened waste-activated sludge (TWAS). Partial factorial design with four levels of (0, 600, 1500, and 3000 KJ/Kg) for ultrasonication and 0, 0.7, 1.4, and 2.8 mg HNO2-N/L for FNA dose were examined creating 16 different combinations. Results revealed that combined pretreatment could significantly improve solubilization and solid destruction compared to solo pretreatments. The highest organic matter solubilization of 25.6% and volatile suspended solids destruction of 21.7% were observed when 2.8 mg HNO2-N/L and 1500 KJ/Kg were combined. Moreover, combining the pretreatments further enhanced biodegradability up to the highest percentage of 50.3% when pretreatment of 3000 KJ/Kg and 2.8 mg HNO2-N/L was applied. Also, the experimental data from a biochemical methane potential test was fitted well into First Order Kinetic and Modified Gompertz models, given that the coefficients of determination, R2, for models at all treatment levels were above 99%.
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Affiliation(s)
- Frances Okoye
- Environmental Research Group for Resource Recovery, Department of Civil Engineering, Faculty of Engineering, Architecture and Science, Ryerson University, Toronto, Canada
| | - Farokh Laqa Kakar
- Environmental Research Group for Resource Recovery, Department of Civil Engineering, Faculty of Engineering, Architecture and Science, Ryerson University, Toronto, Canada
| | - Elsayed Elbeshbishy
- Environmental Research Group for Resource Recovery, Department of Civil Engineering, Faculty of Engineering, Architecture and Science, Ryerson University, Toronto, Canada
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3
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Guo H, Liu S, Wang Y, Hou J, Zhu T, Liu Y. A novel free nitrous acid (FNA)-generation pathway via ferric salts hydrolysis to mitigate sulfide and methane production in sewer: Insights into the performance and microbial mechanisms. JOURNAL OF HAZARDOUS MATERIALS 2023; 459:132284. [PMID: 37591170 DOI: 10.1016/j.jhazmat.2023.132284] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2023] [Revised: 07/26/2023] [Accepted: 08/11/2023] [Indexed: 08/19/2023]
Abstract
Ferric chloride (FeCl3) served as a solid acid has attracted attention recently. However, the feasibility of FeCl3 combined with nitrite for free nitrous acid (FNA) generation in controlling sulfide and methane as well as the triggering mechanisms in the complex syntrophic consortium (i.e., sewer biofilm) remain largely unknown. This work disclosed FeCl3 as an alternative acid source could obtain comparable sulfide and methane mitigations at a low FNA dose (i.e., 0.26 mg N/L), compared to that of HCl acid source. Whereas, a faster recovery rate of sulfide production was observed using FeCl3 under a higher FNA dose (i.e., 0.81 mg N/L) despite the methane control still being comparable. The toxicological mechanisms revealed FNA reacted with proteins amide Ⅰ in extracellular polymeric substances and destroyed protein hydrogen bond. Enzymatic and genic analysis unveiled the overall suppression of hydrolysis, acidogenesis, acetogenesis, sulfidogenesis and methanogenesis steps due to the inactivation of viable cells by reactive nitrogen species. Economic and environmental assessments demonstrated that the ferric-based FNA strategy reduced chemical costs and N2O emission (ca. 26.5% decrease) compared to the traditional HCl-based FNA method. This work broadens the application of iron salt-based technology in urban water system, together with understanding the biological mechanisms of FNA-based technology.
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Affiliation(s)
- Haixiao Guo
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Siru Liu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Yufen Wang
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Jiaqi Hou
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Tingting Zhu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China
| | - Yiwen Liu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China.
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4
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Ni G, Leung PM, Daebeler A, Guo J, Hu S, Cook P, Nicol GW, Daims H, Greening C. Nitrification in acidic and alkaline environments. Essays Biochem 2023; 67:753-768. [PMID: 37449414 PMCID: PMC10427799 DOI: 10.1042/ebc20220194] [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: 03/31/2023] [Revised: 06/27/2023] [Accepted: 06/29/2023] [Indexed: 07/18/2023]
Abstract
Aerobic nitrification is a key process in the global nitrogen cycle mediated by microorganisms. While nitrification has primarily been studied in near-neutral environments, this process occurs at a wide range of pH values, spanning ecosystems from acidic soils to soda lakes. Aerobic nitrification primarily occurs through the activities of ammonia-oxidising bacteria and archaea, nitrite-oxidising bacteria, and complete ammonia-oxidising (comammox) bacteria adapted to these environments. Here, we review the literature and identify knowledge gaps on the metabolic diversity, ecological distribution, and physiological adaptations of nitrifying microorganisms in acidic and alkaline environments. We emphasise that nitrifying microorganisms depend on a suite of physiological adaptations to maintain pH homeostasis, acquire energy and carbon sources, detoxify reactive nitrogen species, and generate a membrane potential at pH extremes. We also recognize the broader implications of their activities primarily in acidic environments, with a focus on agricultural productivity and nitrous oxide emissions, as well as promising applications in treating municipal wastewater.
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Affiliation(s)
- Gaofeng Ni
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia
| | - Pok Man Leung
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia
| | - Anne Daebeler
- Institute of Soil Biology and Biogeochemistry, Biology Centre CAS, Ceske Budejovice, Czechia
| | - Jianhua Guo
- Australian Centre for Water and Environmental Biotechnology (Formerly AWMC), The University of Queensland, Brisbane, Queensland, Australia
| | - Shihu Hu
- Australian Centre for Water and Environmental Biotechnology (Formerly AWMC), The University of Queensland, Brisbane, Queensland, Australia
| | - Perran Cook
- School of Chemistry, Monash University, Melbourne, Victoria, Australia
| | - Graeme W Nicol
- Univ Lyon, CNRS, INSA Lyon, Université Claude Bernard Lyon 1, Ecole Centrale de Lyon, Ampère, UMR5005, 69134 Ecully, France
| | - Holger Daims
- Division of Microbial Ecology, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
- The Comammox Research Platform, University of Vienna, Vienna, Austria
| | - Chris Greening
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia
- Securing Antarctica's Environmental Future, Monash University, Melbourne, Victoria, Australia
- Centre to Impact AMR, Monash University, Melbourne, Victoria, Australia
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5
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Han Z, Shao B, Lei L, Pang R, Wu D, Tai J, Xie B, Su Y. The role of pretreatments in handling antibiotic resistance genes in anaerobic sludge digestion - A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 869:161799. [PMID: 36709893 DOI: 10.1016/j.scitotenv.2023.161799] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 01/07/2023] [Accepted: 01/19/2023] [Indexed: 06/18/2023]
Abstract
Sludge is among the most important reservoirs of antibiotic resistance genes (ARGs), which would cause potential environmental risks with the sludge utilization. Currently, anaerobic digestion (AD) is effective to simultaneously realize the resource recovery and pollutants removal, including antibiotic resistance genes (ARGs), and various pretreatments are used to enhance the performance. Recently, plentiful publications have focused on the effects of pretreatment on ARGs removal, but the contradictory results are often obtained, and a comprehensive understanding of the research progress and mechanisms is essential. This study summarizes various pretreatment techniques for improving AD efficiency and ARGs reduction, investigates promising performance in ARGs removal when pretreatments combined with AD, and analyzes the potential mechanisms accounting for ARGs fates. The results showed that although thermal hydrolysis pretreatment showed the best performance in ARGs reduction during the pretreatment process, the significant rebound of ARGs would occur in the subsequent AD process. Conversely, ozone pretreatment and alkali pretreatment had no significant effect on ARGs abundance in the pretreatment stage, but could enhance ARGs removal by 15.6-24.3 % in the subsequent AD. Considering the efficiency and economic effectiveness, free nitrous acid pretreatment would be a promising and feasible option, which could enhance methane yield and ARGs removal by up to 27 % and 74.5 %, respectively. Currently, the factors determining ARGs fates during pretreatment and AD processes included the shift of microbial community, mobile genetic elements (MGEs), and environmental factors. A comprehensive understanding of the relationship between the fate of ARGs and pretreatment technologies could be helpful for systematically evaluating various pretreatments and facilitating the development of emerging and effective pretreatment techniques. Moreover, given the effectiveness, economic efficiency and environmental safety, we called for the applications of modern analysis approaches such as metagenomic and machine learning on the optimization of pretreatment conditions and revealing underlying mechanisms.
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Affiliation(s)
- Zhibang Han
- Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
| | - Boqun Shao
- Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
| | - Lang Lei
- Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
| | - Ruirui Pang
- Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
| | - Dong Wu
- Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China; Engineering Research Center for Nanophotonics & Advanced Instrument, Ministry of Education, East China Normal University, Shanghai 200241, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Jun Tai
- Shanghai Environmental Sanitation Engineering Design Institute Co., Ltd., Shanghai 200232, China
| | - Bing Xie
- Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China; Engineering Research Center for Nanophotonics & Advanced Instrument, Ministry of Education, East China Normal University, Shanghai 200241, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Yinglong Su
- Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China; Engineering Research Center for Nanophotonics & Advanced Instrument, Ministry of Education, East China Normal University, Shanghai 200241, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China; Chongqing Key Laboratory of Precision Optics, Chongqing Institute of East China Normal University, Chongqing 401120, China.
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6
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Liu W, Li J, Li X, Tian Y, Meng J, Zheng M, Yuan Z. Increasing the removal efficiency of antibiotic resistance through anaerobic digestion with free nitrous acid pretreatment. JOURNAL OF HAZARDOUS MATERIALS 2022; 438:129535. [PMID: 35816802 DOI: 10.1016/j.jhazmat.2022.129535] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 06/30/2022] [Accepted: 07/02/2022] [Indexed: 06/15/2023]
Abstract
Swine manure is a significant reservoir for antibiotic resistance. Anaerobic digestion (AD) is a common biological process used to treat swine manure but still faces low efficiencies in biogas production and antibiotic resistance removal. It is here shown that AD with free nitrous acid pretreatment (FNA) was effective in reducing antibiotic resistance genes (ARGs) in swine manure. FNA pretreatment (nitrite =250 mg N/L, pH=5.0, temperature=20 ± 1 °C) simultaneously reduced antibiotics (Tetracyclines, Quinones and Sulfonamides), inactivated antibiotics resistance bacteria (ARB) by 0.5-3 logs, and decreased ARGs tet, sul and qnr by 1-2, 1-3 and 0.5 logs, respectively. In the following AD step, the total residual ARGs was reduced to ~3.49 × 107 gene copies/g dry total solids (TS), ~1 log lower than that in the AD without pretreatment (3.55 ×108 gene copies/g dry TS). Microbial community and network analyses revealed that the ARG removal was mainly driven by the direct FNA effect on reducing ARGs and antibiotics, not related to ARB. Besides, the FNA pretreatment doubled biochemical methane production potential from swine manure. Together these results demonstrate that AD with FNA pretreatment is a useful process greatly facilitating swine manure management.
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Affiliation(s)
- Wenbin Liu
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 73 Huanghe Road, Harbin 150090, China
| | - Jianzheng Li
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 73 Huanghe Road, Harbin 150090, China
| | - Xianhui Li
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 73 Huanghe Road, Harbin 150090, China
| | - Yajie Tian
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 73 Huanghe Road, Harbin 150090, China
| | - Jia Meng
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 73 Huanghe Road, Harbin 150090, China.
| | - Min Zheng
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, St Lucia, QLD 4072, Australia
| | - Zhiguo Yuan
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, St Lucia, QLD 4072, Australia
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7
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Xu Y, Wang N, Peng L, Li S, Liang C, Song K, Song S, Zhou Y. Free Nitrous Acid Inhibits Atenolol Removal during the Sidestream Partial Nitritation Process through Regulating Microbial-Induced Metabolic Types. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:11614-11624. [PMID: 35900075 DOI: 10.1021/acs.est.1c08845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Limited studies have attempted to evaluate pharmaceutical removal during the sidestream partial nitritation (PN) process. In this work, atenolol biodegradation by PN cultures was investigated by maintaining ammonium and pH at different levels. For the first time, free nitrous acid (FNA), other than ammonium, pH, and free ammonia, was demonstrated to inhibit atenolol removal, with biodegradation efficiencies of ∼98, ∼67, and ∼28% within 6 days at average FNA levels of 0, 0.03, and 0.19 mg-N L-1, respectively. Ammonia-oxidizing bacteria (AOB)-induced metabolism was predominant despite varying FNA concentrations. In the absence of ammonium/FNA, atenolol was mostly biodegraded via AOB-induced metabolism (65%) and heterotroph-induced metabolism (33%). AOB-induced metabolism was largely inhibited (down to 29%) at 0.03 mg-N L-1 FNA, while ∼27 and ∼11% were degraded via heterotroph-induced metabolism and AOB-induced cometabolism, respectively. Higher FNA (0.19 mg-N L-1) substantially reduced atenolol biodegradation via heterotroph-induced metabolism (4%), AOB-induced metabolism (16%), and AOB-induced cometabolism (8%). Newly identified products and pathways were related to metabolic types and FNA levels: (i) deamination and decarbonylation (AOB-induced cometabolism, 0.03 mg-N L-1 FNA); (ii) deamination from atenolol acid (heterotrophic biodegradation); and (iii) nitro-substitution (reaction with nitrite). This suggests limiting FNA to realize simultaneous nitrogen and pharmaceutical removal during the sidestream process.
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Affiliation(s)
- Yifeng Xu
- Hubei Key Laboratory of Mineral Resources Processing and Environment, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070, China
- School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070, China
| | - Ning Wang
- School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070, China
| | - Lai Peng
- Hubei Key Laboratory of Mineral Resources Processing and Environment, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070, China
- School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070, China
| | - Shengjun Li
- School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070, China
| | - Chuanzhou Liang
- Hubei Key Laboratory of Mineral Resources Processing and Environment, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070, China
- School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070, China
| | - Kang Song
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei 430072, China
| | - Shaoxian Song
- Hubei Key Laboratory of Mineral Resources Processing and Environment, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070, China
- School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei 430070, China
| | - Yan Zhou
- School of Civil and Environmental Engineering, Nanyang Technological University, 639798 Singapore
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8
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Chislett M, Yu Z, Donose BC, Guo J, Yuan Z. Understanding the Effect of Free Nitrous Acid on Biofilms. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:11625-11634. [PMID: 35913828 DOI: 10.1021/acs.est.2c01156] [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] [Indexed: 06/15/2023]
Abstract
Free nitrous acid (FNA, i.e., HNO2) has been recently applied to biofilm control in wastewater management. The mechanism triggering biofilm detachment upon exposure to FNA still remains largely unknown. In this work, we aim to prove that FNA induces biofilm dispersal via extracellular polymeric matrix breakdown and cell lysis. Biofilms formed by a model organism, Pseudomonas aeruginosa PAO1, were treated with FNA at concentrations ranging from 0.2 to 15 mg N/L for 24 h (conditions typically used in applications). The biofilms and suspended biomass were monitored both before and after FNA treatment using a range of methods including optical density measurements, viability assays, confocal laser scanning microscopy, and atomic force microscopy. It was revealed that FNA treatment caused substantial and concentration-dependent biofilm detachment. The addition of a reactive nitrogen species (RNS) scavenger, that is, 2-4-carboxyphenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, substantially reduced biofilm dispersal, suggesting that the nitrosative decomposition species of HNO2 (i.e., RNS, e.g., •NO + •NO2) were mainly responsible for the effects. The study provides insight into and support for the use of FNA for biofilm control in wastewater treatment.
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Affiliation(s)
- Mariella Chislett
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, St. Lucia, Brisbane, Queensland 4072, Australia
| | - Zhigang Yu
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, St. Lucia, Brisbane, Queensland 4072, Australia
| | - Bogdan C Donose
- School of Information Technology and Electrical Engineering, The University of Queensland, St Lucia, Brisbane, Queensland 4072, Australia
| | - Jianhua Guo
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, St. Lucia, Brisbane, Queensland 4072, Australia
| | - Zhiguo Yuan
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, St. Lucia, Brisbane, Queensland 4072, Australia
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9
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Chislett M, Guo J, Bond PL, Wang Y, Donose BC, Yuan Z. Reactive nitrogen species from free nitrous acid (FNA) cause cell lysis. WATER RESEARCH 2022; 217:118401. [PMID: 35427827 DOI: 10.1016/j.watres.2022.118401] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Revised: 04/01/2022] [Accepted: 04/04/2022] [Indexed: 06/14/2023]
Abstract
Free nitrous acid (FNA, i.e. HNO2) has been demonstrated to have broad biocidal effects on a range of microorganisms, which has direct implications for wastewater management. However, the biocidal mechanisms still remain largely unknown. This study aims to test the hypothesis that FNA will induce cell lysis via cell membrane perforations, and consequently cause cell death via proteolysis, through the use of two model organisms namely Escherichia coli K12 and Pseudomonas putida KT2440. A combination of analytical techniques that included viability assays, atomic force microscopy (AFM), protein abundance assays and proteomic analysis using Quadruple-Orbitrap™ Mass spectrometry was used to evaluate the extent of cell death and possible cell lysis mechanisms. FNA treatment at 6.09 mg/L for 24 h (conditions typically applied in applications) induced 36 ± 4.2% and 91 ± 3.5% cell death/lysis of E. coli and P. putida, respectively. AFM showed that the lysis of cells was observed via perforations in the cell membrane; cells also appeared to shrink and become flat following FNA treatment. By introducing a reactive nitrogen species (RNS) scavenger to act as a treatment control, we further revealed that it was the nitrosative decomposition species of FNA, such as .NO that caused the cell lysis through the destruction of protein macromolecules found in the cell membrane (proteolysis). Subsequently, the RNS went on to cause the destruction of protein macromolecules within the cells. The death of these model organisms E. coli and P. putida following exposure to FNA treatment provides insights into the use of FNA as an antimicrobial agent in wastewater treatment.
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Affiliation(s)
- Mariella Chislett
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Jianhua Guo
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Philip L Bond
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Yue Wang
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Bogdan C Donose
- School of Information Technology and Electrical Engineering, The University of Queensland, St Lucia, Brisbane, QLD 4072, Australia
| | - Zhiguo Yuan
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, St. Lucia, Queensland 4072, Australia
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10
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Hu ZY, Wang S, Geng ZQ, Dai K, Ji WX, Tian YC, Li WT, Zeng RJ, Zhang F. Controlling volatile fatty acids production from waste activated sludge by an alginate-degrading consortium. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 806:150730. [PMID: 34606857 DOI: 10.1016/j.scitotenv.2021.150730] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Revised: 09/26/2021] [Accepted: 09/28/2021] [Indexed: 06/13/2023]
Abstract
It is desirable to control volatile fatty acids (VFAs) recovery from waste activated sludge (WAS) while avoiding the release of N and P. Structural extracellular polymeric substances (St-EPS), with typical components of alginate and polygalacturonic acid, resist the biodegradation of extracellular polymeric substances (EPS) in WAS. Previously, we purposely enriched an alginate-degrading consortium (ADC), but, both controlling VFAs production and cell integrity after dosing with ADC were not investigated. In this work, ADC with a high percentage of the genus Bacteroides (~67%) was further enriched with alginate utilization above 95%. The St-EPS content in WAS was 109.7 ± 3.3 mg/g-VSS, accounting for 31% of EPS. After dosing ADC in the WAS, the main metabolites were acetate (1.6 g/L) and propionate (0.7 g/L), the hydrolysis efficiency was increased to 38%, and the acidification efficiency was increased to 72%. Cell integrity was maintained during WAS fermentation by dosing with ADC according to no P release and unchanged lactate dehydrogenase activity. VFA production was mainly from the EPS, and protein degradation in EPS resulted in low N release (e.g., 212 mg/L from casein and no P release). Consequently, ADC doing offers the advantages of controlling VFAs production from EPS while maintaining cell integrity.
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Affiliation(s)
- Zhi-Yi Hu
- Center of Wastewater Resource Recovery, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Shuai Wang
- Center of Wastewater Resource Recovery, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Zi-Qian Geng
- Center of Wastewater Resource Recovery, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Kun Dai
- Center of Wastewater Resource Recovery, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Wen-Xiang Ji
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Ye-Chao Tian
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Wen-Tao Li
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Raymond Jianxiong Zeng
- Center of Wastewater Resource Recovery, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Fang Zhang
- Center of Wastewater Resource Recovery, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China.
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11
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Calderon AG, Duan H, Seo KY, Macintosh C, Astals S, Li K, Wan J, Li H, Maulani N, Lim ZK, Yuan Z, Hu S. The origin of waste activated sludge affects the enhancement of anaerobic digestion by free nitrous acid pre-treatment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 795:148831. [PMID: 34246135 DOI: 10.1016/j.scitotenv.2021.148831] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 06/29/2021] [Accepted: 06/29/2021] [Indexed: 06/13/2023]
Abstract
Anaerobic digestion is a common stabilization method for treating primary sludge (PS) and waste activated sludge (WAS). However, its application is often limited by the degradation of WAS. Recent studies have demonstrated FNA to be an effective pre-treatment for enhancing WAS degradability, while having limited effect on PS degradability. WAS characteristics are impacted by wastewater treatment plant (WWTP) configuration and this study is the first to compare the effectiveness of FNA pre-treatment on WAS from WWTP with and without primary treatment. In this study, WAS samples were collected from four full-scale WWTPs with or without primary treatment. Sludge characterization, biomethane potential tests and mathematical modeling were conducted to assess the impacts of FNA pre-treatment on anaerobic digestion. The results showed that FNA pre-treatment was consistently effective for WAS from different WWTPs, while the extent of enhancement varied between WWTPs. For WAS from WWTPs without primary treatment, FNA pretreatment increased the rate of hydrolysis by 54-66% compared to 22-33% increase for WAS without primary treatment. In contrast, WAS from WWTPs with primary treatment experienced greater increases in methane potential (22-24%) compared to WAS from WWTPs without primary treatment (14-16%). These variances could be associated with primary treatment impacting the wastewater COD/N ratio and thus portion of extracellular polymetric substances (EPS) and cells in WAS. FNA pre-treatment targets the destruction of polymetric substances and cells, therefore WAS with a higher proportion of cells (i.e., WAS with primary treatment) experienced greater improvements in methane yield. Similarly, greater improvements in hydrolysis rate were observed for WAS from WWTP without primary sedimentation which contain higher proportions of large EPS molecules. Despite its consistent effectiveness on WAS samples, FNA pre-treatment was ineffective for improving the digestibility of high-rate activated sludge (HRAS).
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Affiliation(s)
| | - Haoran Duan
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia; School of Chemical Engineering, The University of Queensland, St Lucia, QLD 4072, Australia.
| | - Kai Yee Seo
- School of Chemical Engineering, The University of Queensland, St Lucia, QLD 4072, Australia
| | | | - Sergi Astals
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia; Department of Chemical Engineering and Analytical Chemistry, University of Barcelona, C/ Martí i Franquès 1, 08028 Barcelona, Spain
| | - Kaili Li
- School of Chemical Engineering, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Jingjing Wan
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Huijuan Li
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Nova Maulani
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Zhuan Khai Lim
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia
| | - 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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12
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Ren S, Wang Z, Jiang H, Qiu J, Li X, Zhang Q, Peng Y. Stable nitritation of mature landfill leachate via in-situ selective inhibition by free nitrous acid. BIORESOURCE TECHNOLOGY 2021; 340:125647. [PMID: 34385123 DOI: 10.1016/j.biortech.2021.125647] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 07/18/2021] [Accepted: 07/20/2021] [Indexed: 06/13/2023]
Abstract
In-situ free nitrous acid (FNA) and free ammonia (FA) treatments are more feasible than side-stream methods to achieve nitritation. To assess the optimum conditions and long-term performance of in-situ inhibition by FNA, batch tests and a sequencing batch reactor (SBR) treating mature landfill leachate were conducted and established. As a result, the selective inhibition characteristic by FNA was more conspicuous than FA, and FNA (0.175 mg N/L, 6 h) treatment are more biocidal to nitrite oxidizing bacteria (NOB). Moreover, ammonia oxidizing bacteria (AOB) were more sensitive to the FA environment but its activity recovered preferentially compared to NOB. The SBR achieved a sustained nitrite accumulation rate above 90% for 200 days, with a significant decrease of NOB activity and microbial abundance according to qPCR and 16S rRNA gene sequencing results. In-situ selective inhibition by FNA (0.175 mg N/L, 6 h) has been proved to be effective to maintain stable nitritation.
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Affiliation(s)
- Shang Ren
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Zhong Wang
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Hao Jiang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Jingang Qiu
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Xiyao Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Qiong Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.
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13
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Calderon AG, Duan H, Chen X, Wu Z, Yu W, Silva CE, Li Y, Shrestha S, Wang Z, Keller J, Chen Z, Yuan Z, Hu S. Enhancing anaerobic digestion using free nitrous acid: Identifying the optimal pre-treatment condition in continuous operation. WATER RESEARCH 2021; 205:117694. [PMID: 34607085 DOI: 10.1016/j.watres.2021.117694] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 08/17/2021] [Accepted: 09/20/2021] [Indexed: 05/23/2023]
Abstract
Free Nitrous Acid (FNA) pre-treatment is a promising technology demonstrated effective in improving waste activated sludge degradability and anaerobic digestion (AD) performance. Pre-treatment conditions including FNA concentration and treatment duration determine operational and capital cost of full-scale implementation, which have not been studied in long-term experiments. The knowledge of FNA pre-treatment conditions improving the AD performance is urgently required to determine suitable conditions for the technology implementation. In this work, five different FNA concentrations (2.2, 4.4, 7.2, 12 mgN/L and nitrite only without pH adjustment) and three treatment durations (8, 24 and 48 h) were studied in four lab-scale semi-continuous AD reactors for over 300 days. FNA pre-treatment was shown under all tested conditions effective in enhancing AD performances, while its effectiveness and resulted benefits varied substantially amongst different pre-treatment conditions. The long-term experiment demonstrated that the methane production, sludge reduction and digested sludge viscosity of AD are positively correlated with the FNA concentration and durations, until an optimal condition is reached, which was identified in this work to be FNA concentration of 7.2 mgN/L and treatment duration of 24 h. Microbial community changes supported the apparent observation of enhanced sludge degradation at elevating FNA concentrations applied during pre-treatment. The short-term sludge solubilization results were inconsistent with the long-term AD performance, which was potentially caused by inhibitions from stringent FNA pre-treatment conditions applied (FNA = 12 mgN/L with 24-hour treatment & FNA = 7.2 mgN/L with 48-hour treatment). Overall, results suggested FNA pre-treatment at the optimized condition is highly beneficial to WWTPs and competitive with other pre-treatment technologies, e.g., thermal hydrolysis pre-treatment. This work comprehensively evaluated the key design parameters of FNA pre-treatment process, reached a major milestone in the development and applications of FNA technologies.
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Affiliation(s)
| | - Haoran Duan
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia; School of Chemical Engineering, The University of Queensland, St Lucia, QLD 4072, Australia.
| | - Xiaoguang Chen
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia; State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China
| | - Ziping Wu
- School of Chemical Engineering, 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
| | - Carlos E Silva
- Federal University of Piaui Campus Ministro Petronio Portela Ininga, Teresina, PI 64049550, Brazil
| | - Yijing Li
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Sohan Shrestha
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Zhiyao Wang
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Jurg Keller
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD 4072, Australia
| | - Zhongwei Chen
- School of Mechanical and Mining Engineering, The University of Queensland, St Lucia, QLD 4072, Australia
| | - 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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14
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Szypulska D, Miodoński S, Muszyński-Huhajło M, Zięba B, Janiak K. Determination of the major factor responsible for soluble organic matter release during nitrite/free nitrous acid pre-treatment of waste activated sludge. BIORESOURCE TECHNOLOGY 2021; 329:124917. [PMID: 33714926 DOI: 10.1016/j.biortech.2021.124917] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 02/22/2021] [Accepted: 02/24/2021] [Indexed: 06/12/2023]
Abstract
Soluble chemical oxygen demand (SCOD) release by free nitrous acid (FNA)/NO2 system is usually called "FNA disintegration", despite lack of evidence that FNA is the main agent responsible for organic matter breakdown. The aim of this study was to investigate whether FNA or NO2 is the primary disintegration factor of thickened secondary sludge in a wide spectrum of process parameters (T = 48 h, 0-2280 mg NO2-N/L, pH 3.2-6.4 and FNA between 0 and 47.4 mg HNO2-N/L). Statistical analysis based on multiple regression and the Akaike Information Criterion showed that NO2, not FNA, is a main disintegrating factor leading to SCOD release (p = 0.005206 and 0.00009 respectively) and that the FNA concentration is without statistical significance (p = 0.800234 and 0.328099 respectively). These findings are important as understanding key factors is essential for productive future research and technology development. Moreover, these findings give doubts about the role of FNA in its other applications such as inhibition of nitrification.
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Affiliation(s)
- Dorota Szypulska
- Faculty of Environmental Engineering, Wroclaw University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wroclaw, Poland
| | - Stanisław Miodoński
- Faculty of Environmental Engineering, Wroclaw University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wroclaw, Poland
| | - Mateusz Muszyński-Huhajło
- Faculty of Environmental Engineering, Wroclaw University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wroclaw, Poland
| | - Bartosz Zięba
- Faculty of Environmental Engineering, Wroclaw University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wroclaw, Poland
| | - Kamil Janiak
- Faculty of Environmental Engineering, Wroclaw University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wroclaw, Poland; Wroclaw Municipal Water and Sewage Company, Na Grobli 19, 50-421 Wroclaw, Poland.
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15
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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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