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Li X, Luo W, Yang X, Liu T, Tang G, Guo M, Wang M, Zheng X. Operation parameters and temperature affected sludge microbial metabolisms: An integrated perspective considering extracellular polymeric substances, soluble microbial products, biomass quantities, and community shifts. Enzyme Microb Technol 2024; 180:110496. [PMID: 39178646 DOI: 10.1016/j.enzmictec.2024.110496] [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: 06/05/2024] [Revised: 07/21/2024] [Accepted: 08/09/2024] [Indexed: 08/26/2024]
Abstract
Effluent soluble microbial products (SMP) and extracellular polymeric substances (EPS) are significant organics that pose challenges to advanced treatment processes. However, their production, transformation, and decomposition remain unclear due to their heterogeneity and the combined effects of environmental and operational factors. In this work, we investigated the impact of solids retention time (SRT), hydraulic retention time (HRT), and temperature on the changes in effluent SMP, with the consideration of the co-variation of EPS, sludge biomass, and community structures. Results show that longer SRT increased the biomass and relative abundance of functional microorganisms such as Myxococcota, Actinobacteria, and Terrimonas, which hindered EPS-to-SMP turnover and/or facilitated SMP consumption. This resulted in the accumulation of EPS and lower SMP concentrations at the beginning of the SRT adjustment. Both longer and shorter HRT (12 h and 8 h) led to increased SMP concentration, with the shorter HRT nearly doubling it (from approximately 6 to 12 mg/L), especially in terms of its protein and polysaccharide contents. Lower temperatures increased the SMP concentration and the relative abundance of Proteobacteria (including Zoogloea, the most dominant phylum and genus, relative abundance from 15.7 % to 61.1 %) while decreasing fluorescent EPS components, indicating the key role of Proteobacteria in SMP production and fluorescent EPS-to-SMP transformation. The results provided key insights into how changes in operational/environmental parameters impact sludge-EPS-SMP interactions, which could benefit the model development and operational optimization of activated sludge systems. This study also highlighted the important role of the sludge community in the EPS/SMP dynamics.
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Affiliation(s)
- Xiaoliang Li
- State Key Laboratory of Eco-hydraulics in Northwest Arid Region, Xi'an University of Technology, Xi'an 710048, China.
| | - Weiqi Luo
- State Key Laboratory of Eco-hydraulics in Northwest Arid Region, Xi'an University of Technology, Xi'an 710048, China
| | - Xinyu Yang
- State Key Laboratory of Eco-hydraulics in Northwest Arid Region, Xi'an University of Technology, Xi'an 710048, China
| | - Tong Liu
- School of Environment and Natural Resources, Zhejiang University of Science & Technology, Hangzhou 310023, China.
| | - Gang Tang
- Melbourne Climate Futures Academy, Climate & Energy College, School of Geography, Earth and Atmospheric Sciences, The University of Melbourne, Melbourne, VIC 3010, Australia
| | - Mengjing Guo
- State Key Laboratory of Eco-hydraulics in Northwest Arid Region, Xi'an University of Technology, Xi'an 710048, China
| | - Min Wang
- State Key Laboratory of Eco-hydraulics in Northwest Arid Region, Xi'an University of Technology, Xi'an 710048, China
| | - Xing Zheng
- School of Environment and Natural Resources, Zhejiang University of Science & Technology, Hangzhou 310023, China
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Pompa-Pernía A, Molina S, Cherta L, Martínez-García L, Landaburu-Aguirre J. Treatment of Synthetic Wastewater Containing Polystyrene (PS) Nanoplastics by Membrane Bioreactor (MBR): Study of the Effects on Microbial Community and Membrane Fouling. MEMBRANES 2024; 14:174. [PMID: 39195426 DOI: 10.3390/membranes14080174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2024] [Revised: 08/02/2024] [Accepted: 08/03/2024] [Indexed: 08/29/2024]
Abstract
The persistent presence of micro- and nanoplastics (MNPs) in aquatic environments, particularly via effluents from wastewater treatment plants (WWTPs), poses significant ecological risks. This study investigated the removal efficiency of polystyrene nanoplastics (PS-NPs) using a lab-scale aerobic membrane bioreactor (aMBR) equipped with different membrane types: microfiltration (MF), commercial ultrafiltration (c-UF), and recycled ultrafiltration (r-UF) membranes. Performance was assessed using synthetic urban wastewater spiked with PS-NPs, focusing on membrane efficiency, fouling behavior, and microbial community shifts. All aMBR systems achieved high organic matter removal, exceeding a 97% COD reduction in both the control and PS-exposed reactors. While low concentrations of PS-NPs did not significantly impact the sludge settleability or soluble microbial products initially, a higher accumulation increased the carbohydrate concentrations, indicating a protective bacterial response. The microbial community composition also adapted over time under polystyrene stress. All membrane types exhibited substantial NP removal; however, the presence of nano-sized PS particles negatively affected the membrane performance, enhancing the fouling phenomena and increasing transmembrane pressure. Despite this, the r-UF membrane demonstrated comparable efficiency to c-UF, suggesting its potential for sustainable applications. Advanced characterization techniques including pyrolysis gas chromatography/mass spectrometry (Py-GC/MS) were employed for NP detection and quantification.
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Affiliation(s)
- Anamary Pompa-Pernía
- IMDEA Water Institute, Avenida Punto Com, 2, Alcalá de Henares, 28805 Madrid, Spain
- Chemical Engineering Department, University of Alcalá, Ctra. Madrid-Barcelona Km 33.600, Alcalá de Henares, 28871 Madrid, Spain
| | - Serena Molina
- IMDEA Water Institute, Avenida Punto Com, 2, Alcalá de Henares, 28805 Madrid, Spain
| | - Laura Cherta
- IMDEA Water Institute, Avenida Punto Com, 2, Alcalá de Henares, 28805 Madrid, Spain
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Fan XY, Wang YB, Xing-Li, Cao SB, Zhang XH, Geng WN. Redox mediator chlorophyll accelerates low-temperature biological denitrification with responses of extracellular polymers and changes in microbial community composition. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 926:171978. [PMID: 38537813 DOI: 10.1016/j.scitotenv.2024.171978] [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: 01/16/2024] [Revised: 03/15/2024] [Accepted: 03/23/2024] [Indexed: 04/02/2024]
Abstract
Low temperatures limit the denitrification wastewater in activated sludge systems, but this can be mitigated by addition of redox mediators (RMs). Here, the effects of chlorophyll (Chl), 1,2-naphthoquinone-4-sulfonic acid (NQS), humic acid (HA), and riboflavin (RF), each tested at three concentrations, were compared for denitrification performance at low temperature, by monitoring the produced extracellular polymeric substances (EPS), and characterizing microbial communities and their metabolic potential. Chl increased the denitrification rate most, namely 4.12-fold compared to the control, followed by NQS (2.62-fold increase) and HA (1.35-fold increase), but RF had an inhibitory effect. Chl promoted the secretion of tryptophan-like and tyrosine-like proteins in the EPS and aided the conversion of protein from tightly bound EPS into loosely bound EPS, which improved the material transfer efficiency. NQS, HA, and RF also altered the EPS components. The four RMs affected the microbial community structure, whereby both conditionally abundant taxa (CAT) and conditionally rare or abundant taxa (CRAT) were key taxa. Among them, CRAT members interacted most with the other taxa. Chl promoted Flavobacterium enrichment in low-temperature activated sludge systems. In addition, Chl promoted the abundance of nitrate reduction genes narGHI and napAB and of nitrite reduction genes nirKS, norBC, and nosZ. Moreover, Chl increased abundance of genes involved in acetate metabolism and in the TCA cycle, thereby improving carbon source utilization. This study increases our understanding of the enhancement of low-temperature activated sludge by RMs, and demonstrates positive effects, in particular by Chl.
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Affiliation(s)
- Xiao-Yan Fan
- Faculty of Architecture, Civil and Transportation Engineering, Beijing University of Technology, Beijing 100124, PR China.
| | - Ya-Bao Wang
- Faculty of Architecture, Civil and Transportation Engineering, Beijing University of Technology, Beijing 100124, PR China
| | - Xing-Li
- Faculty of Architecture, Civil and Transportation Engineering, Beijing University of Technology, Beijing 100124, PR China
| | - Shen-Bin Cao
- Faculty of Architecture, Civil and Transportation Engineering, Beijing University of Technology, Beijing 100124, PR China
| | - Xiao-Han Zhang
- Faculty of Architecture, Civil and Transportation Engineering, Beijing University of Technology, Beijing 100124, PR China
| | - Wen-Nian Geng
- Faculty of Architecture, Civil and Transportation Engineering, Beijing University of Technology, Beijing 100124, PR China
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Ma W, Han R, Zhang W, Zhang H, Zhao L, Chen L, Zhu L. Advanced oxidation process/coagulation coupled with membrane distillation (AOP/Coag-MD) for efficient ammonia recovery: Elucidating biofouling control performance and mechanism. JOURNAL OF HAZARDOUS MATERIALS 2024; 469:134093. [PMID: 38522199 DOI: 10.1016/j.jhazmat.2024.134093] [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: 01/25/2024] [Revised: 03/03/2024] [Accepted: 03/18/2024] [Indexed: 03/26/2024]
Abstract
The inadequate understanding of the biofouling formation mechanism and the absence of effective control have inhibited the commercial application of membrane distillation (MD). In this study, an advanced oxidation process (AOP)/coagulation-coupled (Coag) membrane distillation system was proposed and exhibited the potential for MD ammonia recovery (recovery rate: 94.1%). Extracellular polymeric substances (EPS) and soluble microbial products (SMP) components such as humic acid and tryptophan-like proteins were disrupted and degraded in the digestate. The curtailment and sterilizing efficiency of AOP on biofilm growth was also verified by optical coherence tomography (OCT) in situ real-time monitoring and confocal laser scanning microscopy (CLSM). Peroxymonosulfate (PMS) was activated to generate sulfate (SO4•-) and hydroxyl radicals (HO•), which altered the microbial community. After oxidative treatment, 16 S rRNA sequencing indicated that the dominant phylum of the microbial community evolved into Firmicutes. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis demonstrated that free radicals produced by PMS could disrupt cells' signaling molecules and interactions. In conjunction with these analyses, the mechanisms of response to free radical attack by Gram-negative bacteria, Gram-positive bacteria, and fungi were revealed. This research provided new insights into the field of membrane fouling control for membrane technology resource recovery processes, broadening the impact of AOP applications on microbiological response and fate in the environment.
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Affiliation(s)
- Wucheng Ma
- Key Laboratory of Integrated Regulation and Resources Development of Shallow Lakes, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China.
| | - Rui Han
- CSD Water Service Co., Ltd. Jiangsu Branch, Nanjing 210000, China
| | - Wei Zhang
- Key Laboratory of Integrated Regulation and Resources Development of Shallow Lakes, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Hao Zhang
- Key Laboratory of Integrated Regulation and Resources Development of Shallow Lakes, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Linting Zhao
- Key Laboratory of Integrated Regulation and Resources Development of Shallow Lakes, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Lin Chen
- Key Laboratory of Integrated Regulation and Resources Development of Shallow Lakes, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China
| | - Liang Zhu
- Key Laboratory of Integrated Regulation and Resources Development of Shallow Lakes, Hohai University, Nanjing 210098, China; College of Environment, Hohai University, Nanjing 210098, China.
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Yan CH, Zhan YF, Chen H, Herman RA, Xu Y, Khurshid M, Gong LC, You S, Wang J. Coupling of gene regulation and carrier modification manipulates bacterial biofilms as robust living catalysts. BIORESOURCE TECHNOLOGY 2024; 399:130604. [PMID: 38499206 DOI: 10.1016/j.biortech.2024.130604] [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: 01/24/2024] [Revised: 03/12/2024] [Accepted: 03/15/2024] [Indexed: 03/20/2024]
Abstract
The biofilm of an engineered strain is limited by slow growth and low yield, resulting in an unsatisfactory ability to resist external stress and promote catalytic efficiency. Here, biofilms used as robust living catalysts were manipulated through dual functionalized gene regulation and carrier modification strategies. The results showed that gene overexpression regulates the autoinducer-2 activity, extracellular polymeric substance content and colony behavior of Escherichia coli, and the biofilm yield of csgD overexpressed strains increased by 79.35 % compared to that of the wild type strains (p < 0.05). In addition, the hydrophilicity of polyurethane fibres modified with potassium dichromate increased significantly, and biofilm adhesion increased by 105.80 %. Finally, the isoquercitrin yield in the catalytic reaction of the biofilm reinforced by the csgD overexpression strain and the modified carrier was 247.85 % higher than that of the untreated group. Overall, this study has developed engineered strains biofilm with special functions, providing possibilities for catalytic applications.
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Affiliation(s)
- Cheng-Hai Yan
- Jiangsu Key Laboratory of Sericultural and Animal Biotechnology, School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu 212100, PR China
| | - Yu-Fan Zhan
- Jiangsu Key Laboratory of Sericultural and Animal Biotechnology, School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu 212100, PR China
| | - Huan Chen
- Jiangsu Key Laboratory of Sericultural and Animal Biotechnology, School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu 212100, PR China
| | - Richard A Herman
- Jiangsu Key Laboratory of Sericultural and Animal Biotechnology, School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu 212100, PR China
| | - Yan Xu
- Jiangsu Key Laboratory of Sericultural and Animal Biotechnology, School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu 212100, PR China; Key Laboratory of Silkworm and Mulberry Genetic Improvement, Ministry of Agriculture and Rural Affairs, Sericultural Scientific Research Center, Chinese Academy of Agricultural Sciences, Zhenjiang, Jiangsu 212100, PR China
| | - Marriam Khurshid
- Jiangsu Key Laboratory of Sericultural and Animal Biotechnology, School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu 212100, PR China
| | - Lu-Chan Gong
- Jiangsu Key Laboratory of Sericultural and Animal Biotechnology, School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu 212100, PR China; Key Laboratory of Silkworm and Mulberry Genetic Improvement, Ministry of Agriculture and Rural Affairs, Sericultural Scientific Research Center, Chinese Academy of Agricultural Sciences, Zhenjiang, Jiangsu 212100, PR China
| | - Shuai You
- Jiangsu Key Laboratory of Sericultural and Animal Biotechnology, School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu 212100, PR China; Key Laboratory of Silkworm and Mulberry Genetic Improvement, Ministry of Agriculture and Rural Affairs, Sericultural Scientific Research Center, Chinese Academy of Agricultural Sciences, Zhenjiang, Jiangsu 212100, PR China
| | - Jun Wang
- Jiangsu Key Laboratory of Sericultural and Animal Biotechnology, School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu 212100, PR China; Key Laboratory of Silkworm and Mulberry Genetic Improvement, Ministry of Agriculture and Rural Affairs, Sericultural Scientific Research Center, Chinese Academy of Agricultural Sciences, Zhenjiang, Jiangsu 212100, PR China; Joint Laboratory of Synthetic Biology and Intelligent Biomanufacturing, Jiangsu University of Technology, Changzhou, Jiangsu 213001, PR China.
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6
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Chen Q, Lü F, Zhang H, Han Y, He P. Dissolved organic nitrogen is a key to improving the biological treatment potential of landfill leachate. WATER RESEARCH 2024; 254:121403. [PMID: 38447377 DOI: 10.1016/j.watres.2024.121403] [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: 11/22/2023] [Revised: 02/02/2024] [Accepted: 02/28/2024] [Indexed: 03/08/2024]
Abstract
Biological treatment is one of the most promising efficient, low-carbon and affordable approaches for the treatment of recalcitrantly degradable wastewater, such as landfill leachate. However, even the macroscopic molecular level analysis of dissolved organic matter (DOM) is limiting to the enhancement of biological treatment efficacy, and there is an urgent need for deeper exploration of DOM to gain insights into the key constraining substances. In the present study targeting at piercing leachate organic at molecular level, nitrogen-containing dissolved organic matter (DOMN) was identified to be the bottleneck that govern the biotreatment potential. The conclusion was made based on two series of experiments that compared the same anoxic-aerobic membrane bioreactor process (A process) operated stably at different regions, and compared with C process that coupling A process with a circulation aeration membrane bioreactor to improve aeration efficiency. The results confirmed that the relative abundance of DOMN was absolutely dominant among the three categories of DOM in all biologically treated samples, contributing to 60.36 %-65.81 % in removed-DOM, 60.33 %-70.95 % in refractory-DOM and 63.14 %-71.36 % in derived-DOM. Specifically, the high latitude A process had much lower DOMN removal rate than the low latitude A process (p < 0.05) and much higher refractory and derivatization rates than the low latitude A process (p < 0.05). DOM had similar results. No statistically significant differences were observed in the proportion of the three categories of DOM (DOMN), the elements composition, and the subcategory composition of the C process compared to the A process, in which the DOM (DOMN) derivation rate of NEC1-C (31.92 % and 33.41 %) was much higher than that of NEC1-A (20.88 % and 22.19 %). However, the AIwa and AImodwa of the derived-DOM (DOMN) were significantly higher in the C process than in the A process, which implied that excessive aeration did not enhance the biological treatment potential of the A process, but instead led to the proliferation of microorganisms and the secretion of extracellular polymer substances, which resulted in the derivation of more complex compounds. The results of the correlation analysis indicated that there were some regional differences in the molecular information of DOMN driven by climate temperature. In addition, it was worth mentioning that the nominal oxidation state of carbon (NOSCwa) of derived-DOMN in different regions of A process was noticeably higher than the corresponding DOM (p < 0.0001), implying that the derived-DOMN were still highly biodegradable, in other words, there was still great room for improving the biological treatment potential of landfill leachate. The present study provided a deeper insight and analysis of landfill leachate at the molecular level (DOMN) through multiple practical engineering cases, with a view to providing a theoretical basis for efficient optimization of biological treatment.
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Affiliation(s)
- Qi Chen
- Institute of Waste Treatment & Reclamation, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China
| | - Fan Lü
- Institute of Waste Treatment & Reclamation, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China.
| | - Hua Zhang
- Institute of Waste Treatment & Reclamation, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
| | - Ying Han
- WELLE Environmental Group Co., Ltd., Xinbei District, Changzhou City, Jiangsu Province 213125, PR China
| | - Pinjing He
- Institute of Waste Treatment & Reclamation, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China.
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Liu X, Yang H, Yang K. Optimizing the hydrolysis-acidification stage in municipal wastewater treatment: comparison of immobilized fillers and granular sludge. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:6288-6300. [PMID: 38147258 DOI: 10.1007/s11356-023-31649-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Accepted: 12/17/2023] [Indexed: 12/27/2023]
Abstract
The decomposition of organic macromolecules in sewage currently benefits substantially from hydrolysis-acidification. The full use of its qualities can help domestic sewage to biodegrade more quickly, which promotes the subsequent aerobic reactions. This study evaluated the hydrolysis-acidification performance of granular sludge and filler in residential sewage. Both forms were highly effective at producing volatile fatty acids (VFAs) at the beginning of the reaction, but the granular sludge gradually disintegrated over time, particularly at low temperatures. The production of VFAs decreased (68.08 mg/L), and the effluent dissolved organic nitrogen (DON) increased (6.23 mg/L). However, the effluent of fillers remained at a lower level (1.3 mg/L) and produced more VFAs (74.13 mg/L). High-throughput sequencing revealed that the filler included a greater quantity of hydrolytic-acidifying bacteria than the granular sludge, which resulted in higher performance. In this study, the optimal form of utilizing hydrolytic acidifying bacteria was discussed to provide a theoretical basis to improve the full utilization of organic matter in domestic sewage and the removal of as much total nitrogen as possible.
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Affiliation(s)
- Xuyan Liu
- Hebei GEO University, Shijiazhuang, 050031, China
- Hebei Province Collaborative Innovation Center for Sustainable Utilization of Water Resources and Optimization of Industrial Structure, Shijiazhuang, 050031, China
| | - Hong Yang
- Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, No. 100, Pingleyuan, Chaoyang District, Beijing, 100124, China
| | - Kai Yang
- Shijiazhuang University, Shijiazhuang, 050035, China.
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Li YQ, Zhao BH, Zhang YQ, Zhang XY, Chen XT, Yang HS. Effects of polyvinylchloride microplastics on the toxicity of nanoparticles and antibiotics to aerobic granular sludge: Nitrogen removal, microbial community and resistance genes. ENVIRONMENTAL RESEARCH 2023; 238:117151. [PMID: 37716388 DOI: 10.1016/j.envres.2023.117151] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 08/30/2023] [Accepted: 09/13/2023] [Indexed: 09/18/2023]
Abstract
Copper oxide nanoparticles (CuO NPs) and ciprofloxacin (CIP) have ecological risk to humans and ecosystems. Polyvinylchloride microplastics (PVC MPs), as a representative of microplastics, may often coexist with CuO NPs and CIP in wastewater treatment systems due to their widespread application. However, the co-impact of PVC MPs in wastewater systems contained with CuO NPs and CIP on nitrogen removal and ecological risk is not clear. In this work, PVC MPs co-impacts on the toxicity of CuO NPs and CIP to aerobic granular sludge (AGS) systems and potential mechanisms were investigated. 10 mg/L PVC MPs co-addition did not significantly affect the nitrogen removal, but it definitely changed the microbial community structure and enhanced the propagation and horizontal transfer of antibiotics resistance genes (ARGs). 100 mg/L PVC MPs co-addition resulted in a raise of CuO NP toxicity to the AGS system, but reduced the co-toxicity of CuO NPs and CIP and ARGs expression. The co-impacts with different PVC MPs concentration influenced Cu2+ concentrations, cell membrane integrity, extracellular polymeric substances (EPS) contents and microbial communities in AGS systems, and lead to a change of nitrogen removal.
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Affiliation(s)
- Yu-Qi Li
- Department of Municipal Engineering, Beijing University of Technology, Beijing, 100124, PR China; Department of Environmental Science and Engineering, Fudan University, Shanghai, 200238, PR China
| | - Bai-Hang Zhao
- Department of Municipal Engineering, Beijing University of Technology, Beijing, 100124, PR China.
| | - Yu-Qing Zhang
- Department of Municipal Engineering, Beijing University of Technology, Beijing, 100124, PR China
| | - Xin-Yue Zhang
- Beijing Municipal Institute of City Management, Beijing, 100028, PR China
| | - Xiao-Tang Chen
- Department of Municipal Engineering, Beijing University of Technology, Beijing, 100124, PR China
| | - Hai-Shan Yang
- Department of Municipal Engineering, Beijing University of Technology, Beijing, 100124, PR China
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Jan S, Mishra AK, Bhat MA, Bhat MA, Jan AT. Pollutants in aquatic system: a frontier perspective of emerging threat and strategies to solve the crisis for safe drinking water. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:113242-113279. [PMID: 37864686 DOI: 10.1007/s11356-023-30302-4] [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: 02/02/2023] [Accepted: 10/03/2023] [Indexed: 10/23/2023]
Abstract
Water is an indispensable natural resource and is the most vital substance for the existence of life on earth. However, due to anthropogenic activities, it is being polluted at an alarming rate which has led to serious concern about water shortage across the world. Moreover, toxic contaminants released into water bodies from various industrial and domestic activities negatively affect aquatic and terrestrial organisms and cause serious diseases such as cancer, renal problems, gastroenteritis, diarrhea, and nausea in humans. Therefore, water treatments that can eliminate toxins are very crucial. Unfortunately, pollution treatment remains a difficulty when four broad considerations are taken into account: effectiveness, reusability, environmental friendliness, and affordability. In this situation, protecting water from contamination or creating affordable remedial techniques has become a serious issue. Although traditional wastewater treatment technologies have existed since antiquity, they are both expensive and inefficient. Nowadays, advanced sustainable technical approaches are being created to replace traditional wastewater treatment processes. The present study reviews the sources, toxicity, and possible remediation techniques of the water contaminants.
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Affiliation(s)
- Saima Jan
- School of Biosciences and Biotechnology, Baba Ghulam Shah Badshah University, Rajouri, 185234, J&K, India
| | | | - Mujtaba Aamir Bhat
- School of Biosciences and Biotechnology, Baba Ghulam Shah Badshah University, Rajouri, 185234, J&K, India
| | - Mudasir Ahmad Bhat
- School of Biosciences and Biotechnology, Baba Ghulam Shah Badshah University, Rajouri, 185234, J&K, India
| | - Arif Tasleem Jan
- School of Biosciences and Biotechnology, Baba Ghulam Shah Badshah University, Rajouri, 185234, J&K, India.
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Pan Y, Sun RZ, Wang Y, Chen GL, Fu YY, Yu HQ. Carbon source shaped microbial ecology, metabolism and performance in denitrification systems. WATER RESEARCH 2023; 243:120330. [PMID: 37482010 DOI: 10.1016/j.watres.2023.120330] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2023] [Revised: 07/07/2023] [Accepted: 07/08/2023] [Indexed: 07/25/2023]
Abstract
The limited information on microbial interactions and metabolic patterns in denitrification systems, especially those fed with different carbon sources, has hindered the establishment of ecological linkages between microscale connections and macroscopic reactor performance. In this work, denitrification performance, metabolic patterns, and ecological structure were investigated in parallel well-controlled bioreactors with four representative carbon sources, i.e., methanol, glycerol, acetate, and glucose. After long-term acclimation, significant differences were observed among the four bioreactors in terms of denitrification rates, organic utilization, and heterotrophic bacterial yields. Different carbon sources induced the succession of denitrifying microbiota toward different ecological structures and exhibited distinct metabolic patterns. Methanol-fed reactors showed distinctive microbial carbon utilization pathways and a more intricate microbial interaction network, leading to significant variations in organic utilization and metabolite production compared to other carbon sources. Three keystone taxa belonging to the Verrucomicrobiota phylum, SJA-15 order and the Kineosphaera genus appeared as network hubs in the methanol, glycerol, and acetate-fed systems, playing essential roles in their ecological functions. Several highly connected species were also identified within the glucose-fed system. The close relationship between microbial metabolites, ecological structures, and system performances suggests that this complex network relationship may greatly contribute to the efficient operation of bioreactors.
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Affiliation(s)
- Yuan Pan
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China; Anhui Province Key Laboratory of Industrial Wastewater and Environmental Treatment, Hefei 230026, China
| | - Rui-Zhe Sun
- School of Resources & Environmental Engineering, Hefei University of Technology, Hefei 230009, China
| | - Yan Wang
- Anhui Province Key Laboratory of Industrial Wastewater and Environmental Treatment, Hefei 230026, China
| | - Guan-Lin Chen
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Ying-Ying Fu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Han-Qing Yu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China.
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11
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Yu J, Xiao K, Xu H, Li Y, Xue Q, Xue W, Zhang A, Wen X, Xu G, Huang X. Spectroscopic fingerprints profiling the polysaccharide/protein/humic architecture of stratified extracellular polymeric substances (EPS) in activated sludge. WATER RESEARCH 2023; 235:119866. [PMID: 36934542 DOI: 10.1016/j.watres.2023.119866] [Citation(s) in RCA: 35] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 02/27/2023] [Accepted: 03/09/2023] [Indexed: 06/18/2023]
Abstract
Extracellular polymeric substances (EPS), with a stratified structure including tightly-bound EPS (TB-EPS), loosely-bound EPS (LB-EPS), and soluble EPS (S-EPS) surrounding the microbial cells, are known to vitally affect the physicochemical and biological functions of activated sludge in wastewater treatment. Polysaccharides (PS), proteins (PN), and humic acids (HA) are key components of EPS but their roles in constructing the multi-layer architecture are still unclear. This study explored the EPS characteristics in relation to the components using spectroscopic fingerprinting techniques. Ultraviolet-visible (UV-vis) spectra demonstrated stark difference between TB-EPS and other EPS. Fluorescence excitation-emission matrix (FEEM) and apparent quantum yield revealed further detailed differences. Fluorescence quotient analysis highlighted the dominance of TB-EPS, LB-EPS, and S-EPS in the excitation/emission wavelength (Ex/Em) region of Em = 350-400 nm, Em > 400 nm, and low-Stokes shift band (Em - Ex < 25 nm), respectively. Wavelength-wise prediction of the FEEM intensity was achieved through multiple linear regression against the chemical composition and variance partitioning analysis witnessed binary interactions of PS×HA and PS×PN in S-EPS, PN×HA and PS×PN in LB-EPS, and ternary interaction of PS×PN×HA in TB-EPS as well as the wavelength-specific fluorescence responses of these interactions. Further, X-ray photoelectron spectroscopy, infrared spectra, and circular dichroism spectra corroborated the differences in primary, secondary, and tertiary structures across the EPS layers. Ultrahigh-performance liquid chromatography-mass spectrometry detected molecular fragments confirming the multi-component hybridization among PS, PN, and HA. This study demonstrates a spectroscopic approach to sensitively fingerprint the fine structure of EPS, which has the potential for rapid monitoring of EPS and related sludge properties in wastewater treatment systems.
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Affiliation(s)
- Jinlan Yu
- Beijing Yanshan Earth Critical Zone National Research Station, University of Chinese Academy of Sciences, Beijing 101408, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, China; State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Kang Xiao
- Beijing Yanshan Earth Critical Zone National Research Station, University of Chinese Academy of Sciences, Beijing 101408, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, China.
| | - Hao Xu
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, China
| | - Yitong Li
- Beijing Yanshan Earth Critical Zone National Research Station, University of Chinese Academy of Sciences, Beijing 101408, China
| | - Qiao Xue
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Wenchao Xue
- Department of Energy, Environment, and Climate Change, School of Environment, Resources, and Development, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathumthani 12120, Thailand
| | - Aiqian Zhang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Xianghua Wen
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
| | - Guoren Xu
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, China
| | - Xia Huang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
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12
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Naderi A, Kakavandi B, Giannakis S, Angelidaki I, Rezaei Kalantary R. Putting the electro-bugs to work: A systematic review of 22 years of advances in bio-electrochemical systems and the parameters governing their performance. ENVIRONMENTAL RESEARCH 2023; 229:115843. [PMID: 37068722 DOI: 10.1016/j.envres.2023.115843] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Revised: 03/25/2023] [Accepted: 04/03/2023] [Indexed: 05/08/2023]
Abstract
Wastewater treatment using bioelectrochemical systems (BESs) can be considered as a technology finding application in versatile areas such as for renewable energy production and simultaneous reducing environmental problems, biosensors, and bioelectrosynthesis. This review paper reports and critically discusses the challenges, and advances in bio-electrochemical studies in the 21st century. To sum and critically analyze the strides of the last 20+ years on the topic, this study first provides a comprehensive analysis on the structure, performance, and application of BESs, which include Microbial Fuel Cells (MFCs), Microbial Electrolysis Cells (MECs) and Microbial Desalination Cells (MDCs). We focus on the effect of various parameters, such as electroactive microbial community structure, electrode material, configuration of bioreactors, anode unit volume, membrane type, initial COD, co-substrates and the nature of the input wastewater in treatment process and the amount of energy and fuel production, with the purpose of showcasing the modes of operation as a guide for future studies. The results of this review show that the BES have great potential in reducing environmental pollution, purifying saltwater, and producing energy and fuel. At a larger scale, it aspires to facilitate the path of achieving sustainable development and practical application of BES in real-world scenarios.
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Affiliation(s)
- Azra Naderi
- Research Center for Environmental Health Technology, Iran University of Medical Sciences, Tehran, Iran; Department of Environmental Health Engineering, School of Public Health, Iran University of Medical Sciences, Tehran, Iran
| | - Babak Kakavandi
- Research Center for Health, Safety and Environment, Alborz University of Medical Sciences, Karaj, Iran; Department of Environmental Health Engineering, Alborz University of Medical Sciences, Karaj, Iran
| | - Stefanos Giannakis
- Universidad Politécnica de Madrid, E.T.S. de Ingenieros de Caminos, Canales y Puertos, Departamento de Ingeniería Civil: Hidráulica, Energía y Medio Ambiente, Environment, Coast and Ocean Research Laboratory (ECOREL-UPM), C/Profesor Aranguren, s/n, ES-28040, Madrid, Spain
| | - Irini Angelidaki
- Department of Chemical and Biochemical Engineering, Technical University of Denmark, DK-2800, Lyngby, Denmark
| | - Roshanak Rezaei Kalantary
- Research Center for Environmental Health Technology, Iran University of Medical Sciences, Tehran, Iran; Department of Environmental Health Engineering, School of Public Health, Iran University of Medical Sciences, Tehran, Iran.
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13
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Qiu J, Li T, Lü F, Huang Y, Li C, Zhang H, Shao L, He P. Molecular behavior and interactions with microbes during anaerobic degradation of bio-derived DOM in waste leachate. J Environ Sci (China) 2023; 126:174-183. [PMID: 36503747 DOI: 10.1016/j.jes.2022.04.015] [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: 03/02/2022] [Revised: 03/30/2022] [Accepted: 04/10/2022] [Indexed: 06/17/2023]
Abstract
It is the key to control bio-derived dissolved organic matters (DOM) in order to reduce the effluent concentration of wastewater treatment, especially for waste leachate with high organic contaminants. In the present study, the anaerobic degradation of aerobically stabilized DOM was investigated with DOM substrate isolated through electrodialysis. The degradation of bio-derived DOM was confirmed by reduction of 15% of total organic carbon in 100 days. We characterized the molecular behavior of bio-derived DOM by coupling molecular and biological information analysis. Venn based Sankey diagram of mass features showed the transformation of bio-derived DOM mass features. Occurrence frequency analysis divided mass features into six categories so as to distinguish the fates of intermediate metabolites and persistent compounds. Reactivity continuum model and machine learning technologies realized the semi-quantitative determination on the kinetics of DOM mass features in the form of pseudo-first order, and confirmed the reduction of inert mass features. Furthermore, network analysis statistically establish relationship between DOM mass features and microbes to identify the active microbes that are able to utilize bio-derived DOM. This work confirmed the biological technology is still effective in controlling recalcitrant bio-derived DOM during wastewater treatment.
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Affiliation(s)
- Junjie Qiu
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, China
| | - Tianqi Li
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, China
| | - Fan Lü
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China; Shanghai Engineering Research Center of Multi-source Solid Wastes Co-Processing and Energy Utilization, Shanghai 200092, China.
| | - Yulong Huang
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, China
| | - Chao Li
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, China
| | - Hua Zhang
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, China
| | - Liming Shao
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China; Shanghai Engineering Research Center of Multi-source Solid Wastes Co-Processing and Energy Utilization, Shanghai 200092, China
| | - Pinjing He
- Institute of Waste Treatment and Reclamation, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China; Shanghai Engineering Research Center of Multi-source Solid Wastes Co-Processing and Energy Utilization, Shanghai 200092, China.
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14
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Wang WQ, Feng XC, Shi HT, Wang YM, Jiang CY, Xiao ZJ, Xu YJ, Zhang X, Yuan Y, Ren NQ. Biofilm inhibition based on controlling the transmembrane transport and extracellular accumulation of quorum sensing signals. ENVIRONMENTAL RESEARCH 2023; 221:115218. [PMID: 36608761 DOI: 10.1016/j.envres.2023.115218] [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: 11/22/2022] [Revised: 12/24/2022] [Accepted: 01/02/2023] [Indexed: 06/17/2023]
Abstract
The regulation of bacterial quorum sensing (QS) has been used to inhibit biofouling in wastewater treatment plants and the formation of biofilms. In contrast to traditional QS regulation strategies, this study aimed to obstruct the transmembrane transport process of QS signals to decrease their extracellular accumulation. Three phytochemicals, astragaloside IV, eugenol, and baicalin were selected, their effects on biofilm formation by Pseudomonas aeruginosa PA14 were studied, and the mechanisms determined. The inhibition efficiency of biofilm formation by 50 mg/L astragaloside IV, 1 mg/L eugenol, and 1 mg/L baicalin were 37%, 26%, and 26%, respectively. Confocal laser scanning microscopy and analysis of extracellular polymeric substances indicated that the three inhibitors affected the structure and composition of the biofilms. Furthermore, bacterial motility and a variety of QS-related virulence factors were suppressed by the inhibitor treatment due to changes in bacterial QS. Notably, the three inhibitors all decreased the extracellular concentration of the QS signaling molecule 3-oxo-C12-homoseine lactone by affecting the function of efflux pump MexAB-OprM. This indirectly interfered with the bacterial QS system and thus inhibited biofilm formation. In conclusion, this study revealed the inhibitory effects and inhibition mechanism of three phytochemicals on efflux pump and QS of P. aeruginosa and realized the inhibition on biofilm formation. We update the efflux pump inhibitor library and provide a new way for biofilm contamination control.
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Affiliation(s)
- Wen-Qian Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen, Guangdong, 518055, PR China
| | - Xiao-Chi Feng
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen, Guangdong, 518055, PR China.
| | - Hong-Tao Shi
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen, Guangdong, 518055, PR China
| | - Yong-Mei Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen, Guangdong, 518055, PR China
| | - Chen-Yi Jiang
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen, Guangdong, 518055, PR China
| | - Zi-Jie Xiao
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen, Guangdong, 518055, PR China
| | - Yu-Jie Xu
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen, Guangdong, 518055, PR China
| | - Xin Zhang
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen, Guangdong, 518055, PR China
| | - Yuan Yuan
- College of Biological Engineering, Beijing Polytechnic, Beijing, 10076, PR China
| | - Nan-Qi Ren
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen, Guangdong, 518055, PR China
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15
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Kakuda T, Naito R, Suzuki A, Hafuka A, Kimura K. Quantitative and qualitative variations of biopolymers in a pilot-scale membrane bioreactor treating municipal wastewater throughout 3 years of operation. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 328:116863. [PMID: 36470001 DOI: 10.1016/j.jenvman.2022.116863] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 11/14/2022] [Accepted: 11/21/2022] [Indexed: 06/17/2023]
Abstract
In this study, the fouling potential of mixed liquor suspension samples collected from a pilot-scale membrane bioreactor (MBR) that treated municipal wastewater was monitored for more than 3 years. The fouling potential was assessed by batch filtration experiments using the same type of membrane as equipped in the MBR. The fouling potential increased when the temperature of the mixed liquor suspension in the MBR decreased. However, the polysaccharide and protein concentrations in the mixed liquor suspension, which have been focused on many previous studies, did not correlate with the fouling potential (R2 = 0.15 and 0.39, respectively). In contrast, the concentration of biopolymers, quantified by liquid chromatography-organic carbon detection (LC-OCD), exhibited a marked correlation with the fouling potential (R2 = 0.89). A high concentration of biopolymers with large molecular weight (>1 million Da) was likely responsible for the high fouling potential. Fourier transform infrared (FTIR) analysis of the dissolved organic matter in the mixed liquor suspension indicated that the chemical properties of the biopolymers considerably varied with the seasonal temperature variation, which has rarely been reported and gives insights into fouling in MBRs. The effect of temperature on the biopolymer concentration and molecular weight of biopolymers was also investigated in a separate bench-scale experiment in which temperature was controlled. It was clearly shown that a low temperature induced an increase in the biopolymer concentration and an associated increase in the fouling potential of the mixed liquor suspension.
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Affiliation(s)
- Takayuki Kakuda
- Faculty of Science and Engineering, Chuo University, Tokyo, 112-8551, Japan.
| | - Rin Naito
- Division of Environmental Engineering, Graduate School of Engineering, Hokkaido University, Sapporo, 060-0828, Japan
| | - Ayana Suzuki
- Division of Environmental Engineering, Graduate School of Engineering, Hokkaido University, Sapporo, 060-0828, Japan
| | - Akira Hafuka
- Division of Environmental Engineering, Graduate School of Engineering, Hokkaido University, Sapporo, 060-0828, Japan
| | - Katsuki Kimura
- Division of Environmental Engineering, Graduate School of Engineering, Hokkaido University, Sapporo, 060-0828, Japan
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16
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Li Z, Cun S, Han G, Guo X, Liu B, Huang T, Hou D, Liu R, Liu X. New insight into soluble extracellular metabolites during sludge bulking process based on excitation-emission matrix spectroscopy and ultrahigh-performance liquid chromatography-mass spectrometry. ENVIRONMENTAL RESEARCH 2023; 219:115161. [PMID: 36580981 DOI: 10.1016/j.envres.2022.115161] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Revised: 12/22/2022] [Accepted: 12/24/2022] [Indexed: 06/17/2023]
Abstract
Soluble extracellular metabolites (SEM) produced by microorganisms might significantly change during sludge bulking, which is a major operational problem caused by the excessive growth of filamentous bacteria. However, knowledge remains limited about the dynamics and potential role of SEM in the bulking of sludge. In this study, filamentous bulking was simulated in a laboratory-scale reactor and changes to SEM characteristics during the bulking process were investigated using excitation-emission matrix spectroscopy and ultrahigh-performance liquid chromatography-mass spectrometry. SEM components changed significantly at different phases of sludge bulking. Changes in SEM were closely correlated with the structure of the bacterial community. Based on the EEM profiles, significant increases in fulvic acid-like and humic acid-like substances in SEM were observed with the development of filamentous bulking. The degree of humification in SEM showed a clear increasing trend. Untargeted extracellular metabolomic analysis showed that the intensity of berberine and isorhamnetin in SEM increased significantly during the bulking phase, which might synergistically facilitate the development of filamentous bulking.
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Affiliation(s)
- Zong Li
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China; RCEES-IMCAS-UCAS Joint-Lab of Microbial Technology for Environmental Science, Beijing, China; Yanshan Earth Critical Zone and Surface Fluxes Research Station, University of Chinese Academy of Sciences, Beijing, China
| | - Shujuan Cun
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China; RCEES-IMCAS-UCAS Joint-Lab of Microbial Technology for Environmental Science, Beijing, China; Yanshan Earth Critical Zone and Surface Fluxes Research Station, University of Chinese Academy of Sciences, Beijing, China
| | - Ganghua Han
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China; RCEES-IMCAS-UCAS Joint-Lab of Microbial Technology for Environmental Science, Beijing, China; Yanshan Earth Critical Zone and Surface Fluxes Research Station, University of Chinese Academy of Sciences, Beijing, China
| | - Xiaoxiao Guo
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China; Yanshan Earth Critical Zone and Surface Fluxes Research Station, University of Chinese Academy of Sciences, Beijing, China
| | - Bingxin Liu
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China; Yanshan Earth Critical Zone and Surface Fluxes Research Station, University of Chinese Academy of Sciences, Beijing, China
| | - Ting Huang
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China; RCEES-IMCAS-UCAS Joint-Lab of Microbial Technology for Environmental Science, Beijing, China; Yanshan Earth Critical Zone and Surface Fluxes Research Station, University of Chinese Academy of Sciences, Beijing, China
| | - Deyin Hou
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China
| | - Ruyin Liu
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China; RCEES-IMCAS-UCAS Joint-Lab of Microbial Technology for Environmental Science, Beijing, China; Yanshan Earth Critical Zone and Surface Fluxes Research Station, University of Chinese Academy of Sciences, Beijing, China.
| | - Xinchun Liu
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China; Yanshan Earth Critical Zone and Surface Fluxes Research Station, University of Chinese Academy of Sciences, Beijing, China.
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17
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Lei C, Chen Y, Li A, Gao R, Zhang Z, Chen J, Shi P, Zhou Q, Ma Y. A new process to further remove dissolved organic matter and disinfection by-product formation potential during drinking water treatment. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:20959-20969. [PMID: 36264461 DOI: 10.1007/s11356-022-23676-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Accepted: 10/12/2022] [Indexed: 06/16/2023]
Abstract
Biological activated carbon (BAC) will produce soluble microbial products (SMPs), which affect effluent quality. To clarify the mechanism by which BAC affects effluent water quality, the processes of a drinking water plant in Jiangsu Province were investigated. It was found that during the O3-BAC process, although ozonation could remove dissolved organic matter (DOC) to a certain extent, the DOC increased from 4.44 to 4.47 mg/L after BAC. Dissolved organic matter (DOM) in effluent from different processes was divided into five fractions based on hydrophilicity and hydrophobicity by resin fractionation. Through fluorescence excitation-emission matrix (EEM) spectroscopy combined with DOC analysis, it was found that SMPs are mainly included in transitional hydrophilic neutral (TPIN) fraction, which was the main cause of the DOC increase. Therefore, a new combined process was designed to remove TPIN effectively by coagulation after biological treatment, and found that coagulation had a good removal rate (13.2%) on TPIN. The trihalomethane formation potential (THMFP) of TPIN could be reduced effectively by 44.9% after coagulation. Compared with the old process, the new combined process had a higher removal rate (14.2-30.0%) of DOC, as well as a greater reduction of THMFP (29.0-78.6%) and haloacetic acid formation potential (HAAFP) (46.4-75.3%). This study aims to reveal the mechanism by which SMPs affect effluent water quality and exacerbate health risks, and to propose a solution to provide theoretical support for the design and optimization of drinking water treatment processes.
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Affiliation(s)
- Chongtian Lei
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, No.163, Xianlin Avenue, Qixia District, Nanjing, 210023, Jiangsu, People's Republic of China
| | - Yurong Chen
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, No.163, Xianlin Avenue, Qixia District, Nanjing, 210023, Jiangsu, People's Republic of China
| | - Aimin Li
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, No.163, Xianlin Avenue, Qixia District, Nanjing, 210023, Jiangsu, People's Republic of China
| | - Rui Gao
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, No.163, Xianlin Avenue, Qixia District, Nanjing, 210023, Jiangsu, People's Republic of China
| | - Ziang Zhang
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, No.163, Xianlin Avenue, Qixia District, Nanjing, 210023, Jiangsu, People's Republic of China
| | - Junxia Chen
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, No.163, Xianlin Avenue, Qixia District, Nanjing, 210023, Jiangsu, People's Republic of China
| | - Peng Shi
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, No.163, Xianlin Avenue, Qixia District, Nanjing, 210023, Jiangsu, People's Republic of China
| | - Qing Zhou
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, No.163, Xianlin Avenue, Qixia District, Nanjing, 210023, Jiangsu, People's Republic of China
| | - Yan Ma
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, No.163, Xianlin Avenue, Qixia District, Nanjing, 210023, Jiangsu, People's Republic of China.
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18
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Zhao W, You J, Yin S, Yang H, He S, Feng L, Li J, Zhao Q, Wei L. Extracellular polymeric substances-antibiotics interaction in activated sludge: A review. ENVIRONMENTAL SCIENCE AND ECOTECHNOLOGY 2023; 13:100212. [PMID: 36425126 PMCID: PMC9678949 DOI: 10.1016/j.ese.2022.100212] [Citation(s) in RCA: 25] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 10/27/2022] [Accepted: 10/28/2022] [Indexed: 05/09/2023]
Abstract
Antibiotics, the most frequently prescribed drugs, have been widely applied to prevent or cure human and veterinary diseases and have undoubtedly led to massive releases into sewer networks and wastewater treatment systems, a hotspot where the occurrence and transformation of antibiotic resistance take place. Extracellular polymeric substances (EPS), biopolymers secreted via microbial activity, play an important role in cell adhesion, nutrient retention, and toxicity resistance. However, the potential roles of sludge EPS related to the resistance and removal of antibiotics are still unclear. This work summarizes the composition and physicochemical characteristics of state-of-the-art microbial EPS, highlights the critical role of EPS in antibiotics removal, evaluates their defense performances under different antibiotics exposures, and analyzes the typical factors that could affect the sorption and biotransformation behavior of antibiotics. Next, interactions between microbial EPS and antibiotic resistance genes are analyzed. Future perspectives, especially the engineering application of microbial EPS for antibiotics toxicity detection and defense, are also emphatically stressed.
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19
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Li YQ, Zhao BH, Chen XT, Zhang YQ, Yang HS. Co-existence effect of copper oxide nanoparticles and ciprofloxacin on simultaneous nitrification, endogenous denitrification, and phosphorus removal by aerobic granular sludge. CHEMOSPHERE 2023; 312:137254. [PMID: 36395892 DOI: 10.1016/j.chemosphere.2022.137254] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 10/25/2022] [Accepted: 11/14/2022] [Indexed: 06/16/2023]
Abstract
Nanoparticles and antibiotics are toxic to humans and ecosystems, and they inevitably coexist in the wastewater treatment plants. Hence, the co-existence effects and stress mechanism of copper (II) oxide nanoparticles (CuO NPs) and ciprofloxacin (CIP) on simultaneous nitrification, endogenous denitrification and phosphorus removal (SNEDPR) by aerobic granular sludge (AGS) were investigated here. The co-existence stress of 5 mg/L CuO NPs and 5 mg/L CIP resulted in the synergistic inhibitory effect on nutrient removal. Transformation inhibition mechanisms of carbon (C), nitrogen (N) and phosphorus (P) with CuO NPs and CIP addition were time-dependent. Furthermore, the long-term stress mainly inhibited PO43--P removal by inhibiting phosphorus release process, while short-term stress mainly inhibited phosphorus uptake process. The synergistic inhibitory effect of CuO NPs and CIP may be due to the changes of physicochemical characteristics under the co-existence of CuO NPs and CIP. This further altered the sludge characteristics, microbial community structure and functional metabolic pathways under the long-term stress. Resistance genes analysis exhibited that the co-existence stress of CuO NPs and CIP induced the amplification of qnrA (2.38 folds), qnrB (4.70 folds) and intI1 (3.41 folds) compared with the control group.
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Affiliation(s)
- Yu-Qi Li
- Department of Municipal Engineering, Beijing University of Technology, Beijing, 100124, PR China
| | - Bai-Hang Zhao
- Department of Municipal Engineering, Beijing University of Technology, Beijing, 100124, PR China.
| | - Xiao-Tang Chen
- Department of Municipal Engineering, Beijing University of Technology, Beijing, 100124, PR China
| | - Yu-Qing Zhang
- Department of Municipal Engineering, Beijing University of Technology, Beijing, 100124, PR China
| | - Hai-Shan Yang
- Department of Municipal Engineering, Beijing University of Technology, Beijing, 100124, PR China
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20
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Sun Y, Su J, Ali A, Zhang S, Zheng Z, Min Y. Effect of fungal pellets on denitrifying bacteria at low carbon to nitrogen ratio: Nitrate removal, extracellular polymeric substances, and potential functions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 847:157591. [PMID: 35901879 DOI: 10.1016/j.scitotenv.2022.157591] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 07/19/2022] [Accepted: 07/19/2022] [Indexed: 06/15/2023]
Abstract
This research aims to elucidate the effect of fungal pellets (FP) on denitrifying bacteria regarding nitrate (NO3--N) removal, extracellular polymeric substances (EPS), and potential functions at a low carbon to nitrogen (C/N) ratio. A symbiotic system of FP and denitrifying bacteria GF2 was established. The symbiotic system showed 100% NO3--N removal efficiency (4.07 mg L-1 h-1) at 6 h and enhanced electron transfer capability at C/N = 1.5. The interactions between FP and denitrifying bacteria promoted the production of polysaccharides (PS) in EPS. Both the increased PS and the PS provided by FP as well as protein and humic acid-like substances in EPS could be consumed by denitrifying bacteria. FP acted as a protector and provided habitat and nutrients for denitrifying bacteria as well as improved the ability of carbohydrate metabolism, amino metabolism, and nitrogen metabolism of denitrifying bacteria. This study provides a new perspective on the relationship between FP and denitrifying bacteria.
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Affiliation(s)
- Yi Sun
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Junfeng Su
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
| | - Amjad Ali
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Shuai Zhang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Zhijie Zheng
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Yitian Min
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
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21
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Lan J, Liu L, Wang X, Wu X, Wang Z. DOM tracking and prediction of rural domestic sewage with UV-vis and EEM in the Yangtze River Delta, China. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:74579-74590. [PMID: 35639319 DOI: 10.1007/s11356-022-20979-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 05/17/2022] [Indexed: 06/15/2023]
Abstract
Compared with the urban sewage treatment plants, the operation of rural decentralized sewage facilities is trapped by the absence of professionals, thus having to be run dependently on the self-adaptive operation of the facilities, which makes timely monitoring particularly important. In this study, organic pollutants in rural domestic sewage and urban domestic sewage are analyzed using ultraviolet-visible (UV-vis) absorption spectroscopy, fluorescence excitation-emission matrix (EEM) and Fourier transform infrared reflectance (FTIR). Compared with the UV-vis absorption spectrum, EEM can not only make up the deficiency in the detection of some easily degradable organics in sewage, but also reveal the transformation of different components, thus indicating timely the treatment progress of rural sewage. Linear fitting of COD and spectrum shows that UV254 combined with fluorescence excitation-emission at Ex/Em = 250/330 nm might be more suitable for the prediction of COD in rural water than the UV254 alone. This is of great significance for guiding the self-adaptive operation of rural domestic sewage facilities, improving their stability and efficiency, so as to improve the rural living environment.
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Affiliation(s)
- Jinjing Lan
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Lili Liu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control On Chemical Process, East China University of Science and Technology, Shanghai, 200237, China
| | - Xu Wang
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control On Chemical Process, East China University of Science and Technology, Shanghai, 200237, China
| | - Xiaoxin Wu
- China-UK Low Carbon College, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - Zhiping Wang
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China.
- China-UK Low Carbon College, Shanghai Jiao Tong University, Shanghai, 200240, China.
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22
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Ling X, Chen M, Cai A, Sun H, Xu S, Wang L, Li X, Deng J. A novel pre-magnetized ZVI/PS pretreatment for improving sludge dewaterability: The role of EPS fractions. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 318:115646. [PMID: 35949095 DOI: 10.1016/j.jenvman.2022.115646] [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: 03/31/2022] [Revised: 06/26/2022] [Accepted: 06/27/2022] [Indexed: 06/15/2023]
Abstract
The dewaterability of waste-activated sludge (WAS) has been extensively examined using zero-valent iron (ZVI)-based advanced oxidation processes (AOPs). However, the high dosage and low utilization efficiencies of ZVI cast doubt on the dependability and viability of ZVI-based AOPs. In this study, we successfully demonstrated pre-magnetization as an efficient, chemical-free, and ecological method for improving the efficiency of sludge dewatering by ZVI/persulfate (PS) process, in which the reduction ratios of capillary suction time (CST) and specific resistance to filtration (SRF) increased by 8.67% and 11.06% under optimal conditions, respectively. The highly active Fe2+ released during ZVI corrosion may be more essential than ZVI itself during PS activation, which could be strengthened by pre-magnetization. Both homogeneous and heterogeneous Fe2+ could react with PS to produce aqueous hydroxyl radicals (∙OH) and sulfate radicals (SO4-∙) as well as surface-bound ∙OH and SO4-∙, further decomposing bound-extracellular polymeric substances fractions, broking hydrophilic functional groups and compounds, altering protein secondary structure to expose more hydrophobic sites, and releasing abundant EPS-bound water. Due to the protection of tightly-bound extracellular polymeric substances (TB-EPS) and the competitive oxidation of organics released during the early disintegration stage, radical oxidation primarily occurs at extracellular levels, releasing a bit of intracellular water. Besides, polysaccharides in TB-EPS may function a more significant role in flocculation than proteins, and a porous structure favorable to drainage will be formed after the pre-magnetized ZVI/PS treatment. The cost-benefit analysis further reveals that the Pre-ZVI/PS process presents high reusability and utilization, making it potential for particle application in sludge dewatering.
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Affiliation(s)
- Xiao Ling
- College of Civil Engineering, Zhejiang University of Technology, Hangzhou 310023, China
| | - Minjie Chen
- College of Civil Engineering, Zhejiang University of Technology, Hangzhou 310023, China
| | - Anhong Cai
- College of Civil Engineering, Zhejiang University of Technology, Hangzhou 310023, China
| | - Honglei Sun
- College of Civil Engineering, Zhejiang University of Technology, Hangzhou 310023, China
| | - Shanlin Xu
- College of Civil Engineering, Zhejiang University of Technology, Hangzhou 310023, China
| | - Lei Wang
- College of Civil Engineering, Zhejiang University of Technology, Hangzhou 310023, China
| | - Xueyan Li
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China
| | - Jing Deng
- College of Civil Engineering, Zhejiang University of Technology, Hangzhou 310023, China.
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23
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Procópio PF, de Aquino SF, Adarme OFH. Aerobic post-treatment of effluent from anaerobic reactors fed with residues from 1G and 2G sugarcane biorefineries. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2022; 94:e10771. [PMID: 35906843 DOI: 10.1002/wer.10771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 07/06/2022] [Accepted: 07/11/2022] [Indexed: 06/15/2023]
Abstract
This study aimed to evaluate an activated sludge system as a post-treatment step of anaerobic effluents from the co-digestion of sugarcane vinasse and hemicelluloses hydrolysate. The system consisted, initially, of a two-stage anaerobic system followed by a continuously fed activated sludge, all in bench scale. After adaptation of aerobic microorganisms to effluent conditions, the anaerobic digestion was conducted in a single-stage anaerobic reactor, increasing the influent organic loading rate (OLR) of activated sludge from 0.73 to an average of 2.36 gCOD/L·day. Under optimal conditions (12-h hydraulic retention time [HRT]), a 62 ± 9% efficiency was observed on the aerobic post-treatment, resulting in effluent chemical oxygen demand (COD) of 414.3 ± 95 mg/L. Overall efficiency of the combined system (anaerobic + aerobic) averaged 88 ± 3%. Influent and effluent characteristics were then analyzed by Folin-Ciocalteau method, UV-Vis spectrophotometry, and gas chromatography-mass spectrometry (GC-MS) for identification of potentially toxic and recalcitrant compounds. Compounds that absorb light within the visible spectra were well removed by the combined treatment system. Most compounds identified by GC-MS in the influent were completely removed by aerobic microorganisms. Saturated fatty acids such as adipic acid, hexadecanoic acid, and octadecanoic acid were observed in the final effluent, as well as other potentially toxic compounds such as stigmasterol, di-isobutyl phthalate, and benzene. Activated sludge proved to be an efficient post-treatment for anaerobic co-digestion, able to cope with changes of anaerobic effluent quality and providing a final effluent of stable organic load. However, phenol removal was not efficient and further studies could be performed to optimize its degradation. PRACTITIONER POINTS: Conventional activated sludge with a 12-h HRT was capable of handling significant OLR variation, providing a final effluent with lower and stable COD concentration. Glucose addition for carbon supplementation was necessary during the start-up of activated sludge. Compounds that absorb light within the visible spectra were mostly removed by the combined (anaerobic-aerobic) treatment system. Most potentially toxic compounds were well removed in the post-treatment system. Saturated fatty acids, VFA, phenols, and low molecular weight aromatic compounds remained in the final effluent.
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Affiliation(s)
- Paula Fontoura Procópio
- Graduate Programme in Environmental Engineering, Federal University of Ouro Preto (UFOP), Ouro Preto, Minas Gerais, Brazil
| | | | - Oscar Fernando Herrera Adarme
- Graduate Programme in Environmental Engineering, Federal University of Ouro Preto (UFOP), Ouro Preto, Minas Gerais, Brazil
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24
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Cai DL, Thanh DTH, Show PL, How SC, Chiu CY, Hsu M, Chia SR, Chen KH, Chang YK. Studies of Protein Wastes Adsorption by Chitosan-Modified Nanofibers Decorated with Dye Wastes in Batch and Continuous Flow Processes: Potential Environmental Applications. MEMBRANES 2022; 12:membranes12080759. [PMID: 36005674 PMCID: PMC9416031 DOI: 10.3390/membranes12080759] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 07/26/2022] [Accepted: 07/30/2022] [Indexed: 01/01/2023]
Abstract
In this study, reactive green 19 dye from wastewater was immobilized on the functionalized chitosan nanofiber membranes to treat soluble microbial proteins in biological wastewater. Polyacrylonitrile nanofiber membrane (PAN) was prepared by the electrospinning technique. After heat treatment, alkaline hydrolysis, and chemically grafted with chitosan to obtain modified chitosan nanofibers (P-COOH-CS), and finally immobilized with RG19 dye, dyed nanofibers were generated (P-COOH-CS-RG19). The synthesis of P-COOH-CS and P-COOH-CS-RG19 are novel materials for protein adsorption that are not deeply investigated currently, with each of the material functions based on their properties in significantly improving the adsorption efficiency. The nanofiber membrane shows good adsorption capacity and great recycling performance, while the application of chitosan and dye acts as the crosslinker in the nanofiber membrane and consists of various functional groups to enhance the adsorption of protein. The dyed nanofibers were applied for the batch adsorption of soluble protein (i.e., lysozyme), and the process parameters including chitosan’s molecular weight, coupling pH, chitosan concentration, dye pH, dye concentration, and lysozyme pH were studied. The results showed that the molecular weight of chitosan was 50 kDa, pH 5, concentration 0.5%, initial concentration of dye at 1 mg/mL dye and pH 12, lysozyme solution at 2 mg/mL at pH 8, and the maximum adsorption capacity was 1293.66 mg/g at a temperature of 318 K. Furthermore, thermodynamic, and kinetic studies suggested that the adsorption behavior of lysozyme followed the Langmuir adsorption isotherm model and the pseudo-second-order kinetic model. The optimal adsorption and desorption conditions based on batch experiments were directly applied to remove lysozyme in a continuous operation. This study demonstrated the potential of dyed nanofibers as an efficient adsorbent to remove approximately 100% of lysozyme from the simulated biological wastewater.
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Affiliation(s)
- Dai-Lun Cai
- Department of Chemical Engineering, Ming Chi University of Technology, New Taipei City 243303, Taiwan; (D.-L.C.); (C.-Y.C.)
| | - Dinh Thi Hong Thanh
- Department of Safety, Health and Environmental Engineering, Ming Chi University of Technology, New Taipei City 243303, Taiwan;
| | - Pau-Loke Show
- Zhejiang Provincial Key Laboratory for Subtropical Water Environment and Marine Biological Resources Protection, Wenzhou University, Wenzhou 325035, China;
- Department of Chemical and Environmental Engineering, Faculty of Science and Engineering, University of Nottingham Malaysia, Semenyih 43500, Malaysia
| | - Su-Chun How
- Department of Chemical Engineering and Biotechnology, Tatung University, Taipei 10452, Taiwan;
| | - Chen-Yaw Chiu
- Department of Chemical Engineering, Ming Chi University of Technology, New Taipei City 243303, Taiwan; (D.-L.C.); (C.-Y.C.)
| | - Michael Hsu
- Chemist Scientific Corp., Taishan Dist., New Taipei City 243303, Taiwan;
| | - Shir Reen Chia
- Institute of Sustainable Energy, Universiti Tenaga Nasional, Jalan IKRAM-UNITEN, Kajang 43000, Malaysia;
| | - Kuei-Hsiang Chen
- Department of Chemical Engineering, Ming Chi University of Technology, New Taipei City 243303, Taiwan; (D.-L.C.); (C.-Y.C.)
- Correspondence: (K.-H.C.); (Y.-K.C.)
| | - Yu-Kaung Chang
- Department of Chemical Engineering, Ming Chi University of Technology, New Taipei City 243303, Taiwan; (D.-L.C.); (C.-Y.C.)
- Correspondence: (K.-H.C.); (Y.-K.C.)
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25
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Evaluation of the impact of SBR operating temperature and filtration temperature on fouling of membranes used for tertiary treatment. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.121194] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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26
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Boron Derivatives Accelerate Biofilm Formation of Recombinant Escherichia coli via Increasing Quorum Sensing System Autoinducer-2 Activity. Int J Mol Sci 2022; 23:ijms23158059. [PMID: 35897636 PMCID: PMC9332218 DOI: 10.3390/ijms23158059] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Revised: 07/19/2022] [Accepted: 07/20/2022] [Indexed: 11/17/2022] Open
Abstract
Boron is an essential element for autoinducer-2 (AI-2) synthesis of quorum sensing (QS) system, which affects bacterial collective behavior. As a living biocatalyst, biofilms can stably catalyze the activity of intracellular enzymes. However, it is unclear how boron affects biofilm formation in E. coli, particularly recombinant E. coli with intracellular enzymes. This study screened different boron derivatives to explore their effect on biofilm formation. The stress response of biofilm formation to boron was illuminated by analyzing AI-2 activity, extracellular polymeric substances (EPS) composition, gene expression levels, etc. Results showed that boron derivatives promote AI-2 activity in QS system. After treatment with H3BO3 (0.6 mM), the AI-2 activity increased by 65.99%, while boron derivatives increased the biomass biofilms in the order H3BO3 > NaBO2 > Na2B4O7 > NaBO3. Moreover, treatment with H3BO3 (0.6 mM) increased biomass by 88.54%. Meanwhile, AI-2 activity had a linear correlation with polysaccharides and protein of EPS at 0−0.6 mM H3BO3 and NaBO2 (R2 > 0.8). Furthermore, H3BO3 upregulated the expression levels of biofilm formation genes, quorum sensing genes, and flagellar movement genes. These findings demonstrated that boron promoted biofilm formation by upregulating the expression levels of biofilm-related genes, improving the QS system AI-2 activity, and increasing EPS secretion in E. coli.
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27
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Gao Z, Su J, Ali A, Wang X, Bai Y, Wang Y, Wang Z. Denitrification strategy of Pantoea sp. MFG10 coupled with microbial dissimilatory manganese reduction: Deciphering the physiological response based on extracellular secretion. BIORESOURCE TECHNOLOGY 2022; 355:127278. [PMID: 35545210 DOI: 10.1016/j.biortech.2022.127278] [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: 04/12/2022] [Revised: 05/03/2022] [Accepted: 05/04/2022] [Indexed: 06/15/2023]
Abstract
In this study, the manganese (Mn) reduction-coupled denitrification strategy of dissimilatory Mn reducing bacteria was insightfully investigated. Different parameters (MnO2 level, pH, and temperature) were optimized by kinetic fitting to improve denitrification and Mn reduction effects. The 300 mg L-1 MnO2 addition achieved 98.72% NO3--N removal in 12 h, which was 54.62% higher than blank group without MnO2. Scale-up studies showed that the metabolic activity of the bacteria was effectively enhanced by the addition of MnO2. Besides the deepening of humification in the system, tryptophan-like protein and polysaccharide as potential electron donor precursors revealed remarkable contributions to the extracellular secretion-dependent denitrification process of DMRB. The effect of EPS on Mn reduction depends mainly on the capture of MnO2 by the LB-EPS layer versus its dissolution in the TB-EPS layer. Ultimately, the EPS possess a dual effect of accelerated denitrification and Mn reduction efficiency due to the enhanced EET process.
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Affiliation(s)
- Zhihong Gao
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Junfeng Su
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
| | - Amjad Ali
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Xumian Wang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Yihan Bai
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Yue Wang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Zhao Wang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
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28
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Zhou Q, Sun H, Jia L, Wu W, Wang J. Simultaneous biological removal of nitrogen and phosphorus from secondary effluent of wastewater treatment plants by advanced treatment: A review. CHEMOSPHERE 2022; 296:134054. [PMID: 35202664 DOI: 10.1016/j.chemosphere.2022.134054] [Citation(s) in RCA: 48] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 02/04/2022] [Accepted: 02/17/2022] [Indexed: 06/14/2023]
Abstract
With the advancement of water ecological protection and water control standard, it is the general trend to upgrade the wastewater treatment plants (WWTPs). The simultaneous removal of nitrogen and phosphorus is the key to improve the water quality of secondary effluent of WWTPs to prevent the eutrophication. Therefore, it is urgent to develop the applicable technologies for simultaneous biological removal of nitrogen and phosphorus from secondary effluent. In this review, the composition of secondary effluent from municipal WWTPs were briefly introduced firstly, then the three main treatment processes for simultaneous nitrogen and phosphorus removal, i.e., the enhanced denitrifying phosphorus removal filter, the pyrite-based autotrophic denitrification and the microalgae biological treatment system were summarized, their performances and mechanisms were analyzed. The influencing factors and microbial community structure were discussed. The advanced removal of nitrogen and phosphorus by different technologies were also compared and summarized in terms of performance, operational characteristics, disadvantage and cost. Finally, the challenges and future prospects of simultaneous removal of nitrogen and phosphorus technologies for secondary effluent were proposed. This review will deepen to understand the principles and applications of the advanced removal of nitrogen and phosphorus and provide some valuable information for upgrading the treatment process of WWTPs.
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Affiliation(s)
- Qi Zhou
- Department of Environmental Science, College of Environmental Sciences and Engineering, Peking University, Beijing, 100871, PR China.
| | - Haimeng Sun
- Department of Environmental Science, College of Environmental Sciences and Engineering, Peking University, Beijing, 100871, PR China.
| | - Lixia Jia
- Department of Environmental Science, College of Environmental Sciences and Engineering, Peking University, Beijing, 100871, PR China.
| | - Weizhong Wu
- Department of Environmental Science, College of Environmental Sciences and Engineering, Peking University, Beijing, 100871, PR China.
| | - Jianlong Wang
- Laboratory of Environmental Technology, INET, Tsinghua University, Beijing, 100084, PR China.
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29
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Zhang HL, Hu YQ, Zhang Y, Qin DN, Wang H. Effects of pure oxygen aeration on organic pollutants removal performance and soluble microbial products characteristics of salt-tolerant activated sludge. ENVIRONMENTAL TECHNOLOGY 2022; 43:1471-1479. [PMID: 33063640 DOI: 10.1080/09593330.2020.1838622] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 10/09/2020] [Indexed: 06/11/2023]
Abstract
The effects of pure oxygen aeration on organic pollutants removal performance and effluent soluble microbial products (SMP) characteristics of salt-tolerant sludge for the treatment of wastewater with the salinity from 1.0% to 3.5% were investigated. The results showed that the oxygen transfer efficiency of the pure oxygen aeration was higher than that of the air aeration. At the low salinities (0.5%, 1.0%, 1.5%), the total organic carbon (TOC) removal rates were 71.42%, 72.88% and 76.30%, respectively, much higher than those with air aeration. However, there were no significant differences of TOC removal efficiency between the air aeration and the pure oxygen aeration at high salinities (2.5% and 3.5%). The SMP contents showed a trend of first decline and then increase generally. The content of SMP with pure oxygen aeration was lower than that with air aeration at low salinity, whereas an opposite result was obtained for salinity above 2.5%. Five excitation-emission matrix (EEM) fluorescence peaks detected in the SMP with pure oxygen aeration and air aeration were assigned to tryptophan protein-like, tyrosine protein-like and humic acid-like substances. Humic acid-like fluorescence mainly appeared in the SMP with air aeration, which may be due to respiratory failure under air aeration conditions.
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Affiliation(s)
- Hong-Ling Zhang
- Nanjing Institute of Environmental Science, MEP, Nanjing, People's Republic of China
- School of the Environment, Nanjing Normal University, Nanjing, People's Republic of China
| | - Ya-Qi Hu
- School of the Environment, Nanjing Normal University, Nanjing, People's Republic of China
| | - Yong Zhang
- School of the Environment, Nanjing Normal University, Nanjing, People's Republic of China
- Key Laboratory of Virtual Geographic Environment (Nanjing Normal University), Ministry of Education, Nanjing, People's Republic of China
- State Key Laboratory Cultivation Base of Geographical Environment Evolution (Jiangsu Province), Nanjing, People's Republic of China
- Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing, People's Republic of China
| | - Dan-Ning Qin
- School of the Environment, Nanjing Normal University, Nanjing, People's Republic of China
| | - Hong Wang
- School of the Environment, Nanjing Normal University, Nanjing, People's Republic of China
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30
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Lim K, Parameswaran P. Critical evaluation of heat extraction temperature on soluble microbial products (SMP) and extracellular polymeric substances (EPS) quantification in wastewater processes. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2022; 85:2318-2331. [PMID: 35486457 DOI: 10.2166/wst.2022.089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
While soluble microbial products (SMP) and extracellular polymeric substances (EPS) in wastewater bioprocesses have been widely studied, a lack of standard quantification procedures make it difficult to compare results between studies. This study investigated the effect of temperature on SMP and EPS profiles for biological nutrient removal (BNR) sludges and aerobic membrane bioreactor sludge by adapting the commonly used heat extraction and centrifugation scheme, followed by colorimetric quantification of the carbohydrate and protein fractions using the phenol-sulfuric acid (PS) and the bicinchoninic acid (BCA) methods, respectively. To overcome known inconsistencies in colorimetry, total carbon (TC), total nitrogen (TN), and fluorometry analyses were performed in tandem. SMP samples marginally benefitted from heat extraction, owing to their mostly soluble nature, while EPS profiles were greatly influenced by temperature. 60 °C appears to be a suitable general-purpose extraction temperature near the lysis threshold for the sludges tested. The PS method's misestimation due to lack of specificity was observed and contrasted by TC analyses, while the TN analyses corroborated the BCA assays. Fluorometry proved to be a sensitive and rapid analytical method that provided semi-quantitative information on SMP and EPS constituents, particularly its proteinaceous components, with positive implications for robust wastewater process control.
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Affiliation(s)
- Kahao Lim
- Department of Civil Engineering, Kansas State University, 2118 Fiedler Hall, 1701C Platt St., Manhattan, KS 66506, USA E-mail:
| | - Prathap Parameswaran
- Department of Civil Engineering, Kansas State University, 2118 Fiedler Hall, 1701C Platt St., Manhattan, KS 66506, USA E-mail:
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31
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Deng S, Wang Q, Cai Q, Ong SL, Hu J. Efficient bio-refractory industrial wastewater treatment with mitigated membrane fouling in a membrane bioreactor strengthened by the micro-scale ZVI@GAC galvanic-cells-initiated radical generation and coagulation processes. WATER RESEARCH 2022; 209:117943. [PMID: 34923441 DOI: 10.1016/j.watres.2021.117943] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Revised: 11/18/2021] [Accepted: 12/04/2021] [Indexed: 06/14/2023]
Abstract
Micro-scale ZVI@GAC-based iron-carbon galvanic-cells (ZVI@GACs) were prepared with the Ca-Si-H/Ca-H formation process and first applied to initiate radical generation and coagulation processes in MBR for treating bio-refractory industrial wastewater (IWW). Batch tests revealed the H2O2 production (0.19-0.28 mg/L) and •OH generation (p-CBA decay, k1 = 0.040 min-1) in ZVI@GACs-dosed system (packing volume of 5%) under aeration. Adoption of ZVI@GACs into aerobic activated sludge process (ZVI@GACs/AS) enhanced TOC degradation (k2) and phenolic compounds (PHENs) destruction (k3). ZVI@GACs/AS at ZVI@GACs packing volume of 5%, 10% and 20% improved k2 from 0.11 h-1 (bare AS) to 0.17, 0.21 and 23 h-1 and k3 from 0.24 h-1 to 0.36, 0.49 and 0.57 h-1, respectively. The oxygen uptake rate (OUR) and 15-min acute bio-toxicity demonstrated that the bio-toxicity of IWW was reduced and the activity of biomass was enhanced in the ZVI@GACs/AS system. In MBR, ZVI@GACs at packing volume of 10% enhanced COD and PHENs removal by 14% and 22%, respectively. Membrane fouling cycle was prolonged by 71%. The accumulations of EPS-proteins, EPS-polysaccharides, SMP-proteins and SMP-polysaccharides were reduced by 6%, 67%, 27% and 60%, respectively. Fourier transform infrared spectroscopy (FTIR) confirmed the oxidation of SMP-polysaccharides in ZVI@GACs-MBR. The iron ions released from ZVI@GACs showed inhibition on the secretion of SMP-/EPS-proteins. Floc particle size distribution (PSD) and X-ray diffraction (XRD) spectrum confirmed that the coagulation effects of Fe(OH)3 and FeOOH triggered by Fe3+ increased the sludge floc size and contributed to membrane fouling mitigation. Genus Enterococcus was enriched in MBR with the destruction of PHENs by the ZVI@GACs-initiated radical generation process. The findings of this study confirmed successful development and adoption of ZVI@GACs into MBR for bio-refractory IWW treatment. It also provided an in-depth understanding on the mechanisms of ZVI@GACs-MBR system.
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Affiliation(s)
- Shihai Deng
- Sembcorp-NUS Corporate Laboratory, Sembcorp-NUS Corporate Laboratory c/o FoE, National University of Singapore, Block E1A, #04-01, 1 Engineering Drive 2, Singapore 117576, Singapore; Department of Civil and Environmental Engineering, Faculty of Engineering, National University of Singapore, Block E1A, #07-01, 1 Engineering Drive 2, Singapore 117576, Singapore
| | - Qi Wang
- Department of Civil and Environmental Engineering, Faculty of Engineering, National University of Singapore, Block E1A, #07-01, 1 Engineering Drive 2, Singapore 117576, Singapore
| | - Qinqing Cai
- Sembcorp-NUS Corporate Laboratory, Sembcorp-NUS Corporate Laboratory c/o FoE, National University of Singapore, Block E1A, #04-01, 1 Engineering Drive 2, Singapore 117576, Singapore; Department of Civil and Environmental Engineering, Faculty of Engineering, National University of Singapore, Block E1A, #07-01, 1 Engineering Drive 2, Singapore 117576, Singapore
| | - Say Leong Ong
- Sembcorp-NUS Corporate Laboratory, Sembcorp-NUS Corporate Laboratory c/o FoE, National University of Singapore, Block E1A, #04-01, 1 Engineering Drive 2, Singapore 117576, Singapore; Department of Civil and Environmental Engineering, Faculty of Engineering, National University of Singapore, Block E1A, #07-01, 1 Engineering Drive 2, Singapore 117576, Singapore
| | - Jiangyong Hu
- Sembcorp-NUS Corporate Laboratory, Sembcorp-NUS Corporate Laboratory c/o FoE, National University of Singapore, Block E1A, #04-01, 1 Engineering Drive 2, Singapore 117576, Singapore; Department of Civil and Environmental Engineering, Faculty of Engineering, National University of Singapore, Block E1A, #07-01, 1 Engineering Drive 2, Singapore 117576, Singapore.
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Yang H, Li Z, Chen Y, Zhou Z. Role of microparticles in membrane fouling from acidogenesis to methanogenesis phases in an anaerobic baffled reactor. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 806:150663. [PMID: 34597561 DOI: 10.1016/j.scitotenv.2021.150663] [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: 07/30/2021] [Revised: 09/24/2021] [Accepted: 09/24/2021] [Indexed: 06/13/2023]
Abstract
Microparticles (0.45-10 μm) have been recognized as key foulants in anaerobic membrane bioreactors (AnMBRs). However, their characteristics and fouling behaviors are often understood in single-stage and completely mixed reactors, failing to elucidate the occurrence of microparticles in the multi-stage anaerobic bioprocess. Here, a lab-scale anaerobic baffled reactor with four compartments (C1-C4) was employed to explore the composition and fouling potential of microparticles in different compartments. Photometric analysis showed that the microparticles had an increasing percentage in the total organics of the top supernatant but a decreasing concentration from C1 to C4. Long-term filtration and dead-end filtration tests revealed that the top supernatant in C1 had much higher fouling potential than those in C2-C4. The supernatant microparticles significantly accumulated in the cake layers for each compartment (68-95% of the total organics), particularly the fraction of 1-5 μm, and the fouling rate was positively correlated with the biomass accumulation rate. Based on reactor performance and 16S rRNA gene sequences, a significant bio-phase separation occurred between C1 (acidogenesis) and C2-C4 (methanogenesis). And hydrolytic and fermentative bacteria in the family Veillonellaceae, Streptococcaceae, and Enterobacteriaceae were dominant in the supernatant microparticles, particularly in C1, which had a positive correlation with the fouling rate and biomass accumulation rate. These above results all revealed that the microparticles in the acidogenesis phase had higher fouling potential. In summary, our results suggest that the tactic of pre-hydrolysis and acidification with feedstocks and constructing AnMBRs by coupling with multi-phase anaerobic bioprocesses and membrane units could be beneficial to fouling control.
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Affiliation(s)
- Houlong Yang
- College of Resources and Environment, Southwest University, Chongqing 400715, China; Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Resources and Environment, Southwest University, Chongqing 400715, China
| | - Zicong Li
- College of Resources and Environment, Southwest University, Chongqing 400715, China; Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Resources and Environment, Southwest University, Chongqing 400715, China
| | - Yucheng Chen
- College of Resources and Environment, Southwest University, Chongqing 400715, China; Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Resources and Environment, Southwest University, Chongqing 400715, China; Chongqing Engineering Research Center of Rural Cleaner Production, Chongqing 400715, China
| | - Zhongbo Zhou
- College of Resources and Environment, Southwest University, Chongqing 400715, China; Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Ministry of Education, College of Resources and Environment, Southwest University, Chongqing 400715, China; Chongqing Engineering Research Center of Rural Cleaner Production, Chongqing 400715, China.
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Lotfikatouli S, Hadi P, Yang M, Walker HW, Hsiao BS, Gobler C, Reichel M, Mao X. Enhanced anti-fouling performance in Membrane Bioreactors using a novel cellulose nanofiber-coated membrane. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2021.119145] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Wang ZY, Ju CJ, Zhang R, Hua JQ, Chen RP, Liu GX, Yin K, Yu L. Acceleration of the bio-reduction of methyl orange by a magnetic and extracellular polymeric substance nanocomposite. JOURNAL OF HAZARDOUS MATERIALS 2021; 420:126576. [PMID: 34252658 DOI: 10.1016/j.jhazmat.2021.126576] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 07/01/2021] [Accepted: 07/02/2021] [Indexed: 06/13/2023]
Abstract
Extracellular electron transfer (EET) plays an important role in bio-reduction of environmental pollutants. Extracellular polymeric substances (EPS), a kind of biogenic macromolecule, contain functional groups responsible for acceleration of EET. In this study, azo dye-methyl orange (MO) was chosen as a model pollutant, and a Fe3O4 and EPS nanocomposite (Fe3O4@EPS) was prepared to evaluate its promotion on the bio-reduction of MO. The flower-like core-shell configuration of Fe3O4@EPS with a 12 nm of light layer of EPS was confirmed by TEM. The redox ability of EPS was well reserved on Fe3O4@EPS by FTIR and electrochemical test. The application of Fe3O4@EPS on sustained acceleration of MO decolorization were confirmed by batch experiments and anaerobic sequenced batch reactors. Due to biocompatibility of the biogenic shell, the as-prepared Fe3O4@EPS exhibited low toxic to microorganisms by the Live/dead cell test. Moreover, negligible leaching of EPS under high concentration of various anions and less than 10% of EPS was released under extreme acidic and basic pH condition. The results of study provided a new preparation method of biological intimate and environmentally friendly redox mediators and suggested a feasible way for its use on bio-reduction of pollutants.
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Affiliation(s)
- Zi-Yang Wang
- Department of Environmental Engineering, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China; School of Environmental Science, Nanjing XiaoZhuang University, Nanjing 211171, China
| | - Cheng-Jia Ju
- Department of Environmental Engineering, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
| | - Rui Zhang
- Department of Environmental Engineering, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
| | - Jing-Qiu Hua
- Department of Environmental Engineering, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
| | - Rong-Ping Chen
- Department of Environmental Engineering, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
| | - Guang-Xiang Liu
- School of Environmental Science, Nanjing XiaoZhuang University, Nanjing 211171, China
| | - Ke Yin
- Department of Environmental Engineering, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
| | - Lei Yu
- Department of Environmental Engineering, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China; School of Environmental Science, Nanjing XiaoZhuang University, Nanjing 211171, China.
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Wei M, Zhang R, Zhou M, Yuan Z, Yuan H, Zhu N. Treatment of fresh leachate by microaeration pretreatment combined with IC-AO 2 process: Performance and mechanistic insight. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 789:147939. [PMID: 34058591 DOI: 10.1016/j.scitotenv.2021.147939] [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: 03/22/2021] [Revised: 05/17/2021] [Accepted: 05/18/2021] [Indexed: 06/12/2023]
Abstract
Fresh leachate is commonly featured with high concentrations of degradable organic matters, which can impede the performance of traditional biological treatment, especially the anaerobic reactor. Aiming at improving the biological treatment process of fresh leachate, this study creatively proposed a microaerobic-IC-AO2 (MAICAO2) process and compared it with traditional biological process, then optimized the operating conditions. Meanwhile, this work investigated the transformation rules and molecular compositions of dissolved organic matters (DOM) during MAICAO2 process, particularly the hazardous DOM (antibiotics). The innovative MAICAO2 process can effectively remove 99% chemical oxygen demand (COD), 91% total nitrogen (TN) and 91% ammonia (NH4+-N) during the operation time, and the removal efficiencies of COD, TN and NH4+-N in MAICAO2 process increased approximately 2%, 14% and 13% compared to ICAOAO process. Electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS) confirmed that microaeration could ensure over 53% small molecular organic acids degrade before the subsequent anaerobic reaction so the system could resist the high concentration organic matters stress and improve the denitrification efficiency. Further analysis showed that different categories of antibiotics (including 6 sulfonamides, 4 tetracyclines, 2 macrolides, 4 quinolones and 2 chloramphenicols) could be effectively removed by MAICAO2 process with the total removal efficiency of 50%. This work proposed a new scenario for fresh leachate treatment by proposing the importance of the microaeration pretreatment during the biological treatment process.
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Affiliation(s)
- Mengqi Wei
- School of Environmental Science & Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Ruina Zhang
- Shanghai Institute for Design & Research on Environmental Engineering Co., Ltd, Shanghai 200040, China; Shanghai Environmental Sanitation Engineering Design Institute Co., Ltd, Shanghai 200001, China
| | - Mingjian Zhou
- School of Environmental Science & Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Zhiqiang Yuan
- School of Environmental Science & Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Haiping Yuan
- School of Environmental Science & Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Nanwen Zhu
- School of Environmental Science & Engineering, Shanghai Jiao Tong University, Shanghai 200240, China; Shanghai Engineering Research Center of Solid Waste Treatment and Resource Recovery, Shanghai 200240, China.
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Suspended membrane bioreactor with extracellular polymeric substances as reserve carbon source for low carbon to nitrogen ratio wastewater: Performance and microbial community composition. KOREAN J CHEM ENG 2021. [DOI: 10.1007/s11814-021-0841-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Chen C, Ali A, Su J, Wang Y, Huang T, Gao J. Pseudomonas stutzeri GF2 augmented the denitrification of low carbon to nitrogen ratio: Possibility for sewage wastewater treatment. BIORESOURCE TECHNOLOGY 2021; 333:125169. [PMID: 33892425 DOI: 10.1016/j.biortech.2021.125169] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 04/06/2021] [Accepted: 04/08/2021] [Indexed: 06/12/2023]
Abstract
A denitrifying strain with high efficiency at low carbon to nitrogen (C/N) ratio of 2.0 was isolated and characterized. It belongs to the genus Pseudomonas. Scanning electron microscopy (SEM) showed that GF2 was rod-shaped. The nitrate removal efficiency reached up to 92.41% (1.85 mg L-1 h-1) with the C/N ratio of 2.0 and the nitrite accumulation eventually decreased to 0.88 mg L-1. By response surface method (RSM) method, three reaction conditions of strain GF2 were optimized, including pH, C/N ratio, and nitrate concentration. Nitrogen balance and gas detection revealed that 88.03% of nitrogen was removed in gaseous form (included 98.80% nitrogen gas), which confirmed its efficient denitrification ability and pathway. 3D fluorescence spectrum (3D-EEM) manifested that in the absence of organic matter, strain GF2 can utilize extracellular polymeric substance (EPS) as carbon source for efficient denitrification. This research strived to provide new research ideas for low C/N ratio sewage treatment.
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Affiliation(s)
- Changlun Chen
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Amjad Ali
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Junfeng Su
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; State Key Laboratory of Green Building in West China, Xi'an University of Architecture and Technology, Xi'an 710055, China.
| | - Yue Wang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Tinglin Huang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; State Key Laboratory of Green Building in West China, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Jing Gao
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
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38
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Tian X, Shen Z, Zhou Y, Wang K. Acidification inhibition, biodechlorination, and biotransformation of chlorinated acetaldehydes on acidogenic sludge and microbial community changes. CHEMOSPHERE 2021; 277:130231. [PMID: 33774258 DOI: 10.1016/j.chemosphere.2021.130231] [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: 08/10/2020] [Revised: 11/04/2020] [Accepted: 03/06/2021] [Indexed: 06/12/2023]
Abstract
Chlorinated acetaldehydes (CALs) are typical chlorinated organic compounds that posing a great threat to biological wastewater treatment plants. In this study, volatile batch acid (VFA) tests were employed to investigate the acidification inhibition, biodechlorination, and biotransformation of high-strength CALs on hydrolytic acidification. The results indicated that the optimum parameters were 4 g/L sludge, pH = 8, and glucose as an electron donor. Moreover, the acidification inhibition and biodechlorination showed a strongly positive correlation with the degree of chlorination and CAL concentrations. Extracellular polymeric substances (EPS) decreased dramatically, while DNA increased sharply under higher CAL concentrations, which was the result of cell death caused by the toxicity of the CALs. Additionally, the relative toxicities of the CALs were as follows: trichloroacetaldehyde > dichloroacetaldehyde > chloroacetaldehyde. Furthermore, Excitation-Emission-Matrix (EEM) spectra of EPS revealed that aromatic protein-like substances I interacted with CALs to achieve a slight removal of CALs. The detected products revealed that some of the chlorine atoms and aldehyde groups in the CALs were removed by microbes to certain degree. Moreover, microbial community analysis indicated that the dominant phyla were Actinobacteria, Bacteroidetes, and Synergistetes, which had a stronger tolerance to CALs. Notably, biodechlorination was closely related to a remarkable increase in members of the genus Trichococcus.
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Affiliation(s)
- Xiangmiao Tian
- School of Environment, Tsinghua University, Beijing, 100084, PR China; State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environment Sciences, Beijing, 100012, PR China; Research Center of Environmental Pollution Control Engineering Technology, Chinese Research Academy of Environmental Sciences, Beijing, 100012, PR China
| | - Zhiqiang Shen
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environment Sciences, Beijing, 100012, PR China; Research Center of Environmental Pollution Control Engineering Technology, Chinese Research Academy of Environmental Sciences, Beijing, 100012, PR China.
| | - Yuexi Zhou
- School of Environment, Tsinghua University, Beijing, 100084, PR China; State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environment Sciences, Beijing, 100012, PR China; Research Center of Environmental Pollution Control Engineering Technology, Chinese Research Academy of Environmental Sciences, Beijing, 100012, PR China.
| | - Kaijun Wang
- School of Environment, Tsinghua University, Beijing, 100084, PR China
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Yang P, Peng Y, Tan H, Liu H, Wu D, Wang X, Li L, Peng X. Foaming mechanisms and control strategies during the anaerobic digestion of organic waste: A critical review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 779:146531. [PMID: 34030228 DOI: 10.1016/j.scitotenv.2021.146531] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2020] [Revised: 03/11/2021] [Accepted: 03/12/2021] [Indexed: 06/12/2023]
Abstract
Foaming is a problem that affects the efficient and stable operation of the anaerobic digestion process. Characterizing foaming mechanisms and developing early warning and foaming control methods is thus critically important. This review summarizes the correlation of process parameters, state parameters, and microbial communities with foaming in anaerobic digesters; discusses the applicability of the above-mentioned multi-scale parameters and foaming potential evaluation methods for the prediction of foaming risk; and introduces the principles and practical applications of antifoaming and defoaming methods. Multiple causes of foaming in anaerobic digestion systems have been identified, but a generalizable foaming mechanism has yet to be described. Further study of the correlation between extracellular polymeric substances and soluble microbial products and foaming may provide new insights into foaming mechanisms. Monitoring the foaming potential (including the volume expansion potential) is an effective approach for estimating the risk of foaming. An in-situ monitoring system for determining the foaming potential in anaerobic digestion sites could provide an early warning of foaming risk. Antifoaming methods based on operating parameter management and process regulation help prevent foaming from the source, and biological defoaming methods are highly targeted and efficient, which is a promising research direction. Clarifying foaming mechanisms will aid the development of active antifoaming methods and efficient biological defoaming methods.
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Affiliation(s)
- Pingjin Yang
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China
| | - Yun Peng
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China
| | - Hanyue Tan
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China
| | - Hengyi Liu
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China
| | - Di Wu
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China
| | - Xiaoming Wang
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China
| | - Lei Li
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China.
| | - Xuya Peng
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China
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40
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Liang J, Zhang L, Zhou Y. Pyrite assisted peroxymonosulfate sludge conditioning: Uncover triclosan transformation during treatment. JOURNAL OF HAZARDOUS MATERIALS 2021; 413:125368. [PMID: 33609874 DOI: 10.1016/j.jhazmat.2021.125368] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/23/2021] [Accepted: 02/07/2021] [Indexed: 06/12/2023]
Abstract
Waste activated sludge (WAS) dewatering is a crucial process for sludge treatment and disposal. In this study, we proposed a novel pyrite (FeS2) and peroxymonosulfate (PMS) treatment to improve WAS dewaterability. Micropollutants are commonly enriched in the sludge. It is not clear if the micropollutants remain in the sludge during the conditioning. Triclosan (TCS) as a widely used bactericide often presents in the WAS, thus was chosen as a target micropollutant. Pyrite + PMS treatment could simultaneously enhance WAS dewaterability and TCS removal with low cost and high benefit. Under the optimal conditions, the specific resistance of filtration (SRF) and capillary suction time (CST) were reduced by 84.60% and 74.91%, respectively. Meanwhile, the TCS removal efficiency was 34.08% with four transformation products identified. During the pyrite + PMS process, sulfate radicals and hydroxyl radicals were generated and strong flocculation was induced by iron. These two processes significantly reduced the sticky biopolymers, hydrophilic functional groups, and hydrophilic protein molecular structure of extracellular polymeric substances (EPS), leading to the release of bound water and TCS. Collectively, the pyrite + PMS treatment is a promising alternative for simultaneous enhancement of WAS dewatering and micropollutants removal, which is beneficial to the downstream treatment.
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Affiliation(s)
- Jialin Liang
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 637141, Singapore; Institute of Bioresource and Agriculture, Department of Biology, Hong Kong Baptist University, Hong Kong, China
| | - Liang Zhang
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 637141, Singapore
| | - Yan Zhou
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 637141, Singapore; School of Civil and Environmental Engineering, Nanyang Technological University, 639798, Singapore.
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41
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Tang G, Li B, Zhang B, Wang C, Zeng G, Zheng X, Liu C. Dynamics of dissolved organic matter and dissolved organic nitrogen during anaerobic/anoxic/oxic treatment processes. BIORESOURCE TECHNOLOGY 2021; 331:125026. [PMID: 33812138 DOI: 10.1016/j.biortech.2021.125026] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 03/13/2021] [Accepted: 03/16/2021] [Indexed: 06/12/2023]
Abstract
With Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) and fluorescence spectroscopy, this study investigated the transformation of dissolved organic matter (DOM) and nitrogen (DON) during the widely-applied anaerobic/anoxic/oxic (A2O) processes to provide molecular insights into the removal, generation, and reduction of DOM/DON species in different biological treatment units. Results indicated that the anaerobic process decomposed the macromolecules of influent DOM/DON and decreased their mass. The anoxic process denitrified DON and generated DOM, as indicated by the decreased molecule number of CHON and CHONS and the increased CHO and CHOS species, as well as the increased overall DOM intensities. DOM mineralization and ammonia nitrogen-DON conversion occurred in the oxic process. Aromaticity and unsaturation degree increased slightly after the A2O processes, which was correlated with the relative abundance of Proteobacteria (positively) and Bacteroidetes (negatively). The results have strong implications to the understanding of DOM/DON dynamics in wastewater treatment plants.
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Affiliation(s)
- Gang Tang
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, PR China
| | - Binrui Li
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, PR China; School of Environment, China University of Geosciences, Wuhan, 430074, PR China
| | - Bowei Zhang
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, PR China
| | - Chen Wang
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, PR China
| | - Guangci Zeng
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, PR China
| | - Xing Zheng
- State Key Laboratory of Eco-hydraulics in Northwest Arid Region, Xi'an University of Technology, Xi'an, 710048, PR China
| | - Chongxuan Liu
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, PR China.
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Removal of protein wastes by cylinder-shaped NaY zeolite adsorbents decorated with heavy metal wastes. Int J Biol Macromol 2021; 185:761-772. [PMID: 34216668 DOI: 10.1016/j.ijbiomac.2021.06.177] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 05/09/2021] [Accepted: 06/27/2021] [Indexed: 01/01/2023]
Abstract
Cylinder-shaped NaY zeolite was used as an adsorbent for eradicating both heavy metal ions (Cu2+, Zn2+, Ni2+, and Co2+) and proteins from the waste streams. As a pseudo-metal ion affinity adsorbent, NaY zeolite was used in the capture of heavy metal ions in the first stage. The amount (molar basis) of metal ions adsorbed onto NaY zeolite decreased in the order of Cu2+ > Zn2+ > Co2+ > Ni2+. Bovine serum albumin (BSA) was utilized as a model of proteins used in the waste adsorption process by NaY zeolite. The adsorption capacities of NaY zeolite and Cu/NaY zeolite for BSA were 14.90 mg BSA/g zeolite and 84.61 mg BSA/g zeolite, respectively. Moreover, Cu/NaY zeolite was highly stable in the solutions made of 2 M NaCl, 500 mM imidazole or 125 mM EDTA solutions. These conditions indicated that the minimal probability of secondary contamination caused by metal ions and soluble proteins in the waste stream. This study demonstrates the potential of Cu/NaY zeolite complex as an efficient pseudo-metal chelate adsorbent that could remove metal ions and water-soluble proteins from wastewater concurrently.
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Lin TY, Chai WS, Chen SJ, Shih JY, Koyande AK, Liu BL, Chang YK. Removal of soluble microbial products and dyes using heavy metal wastes decorated on eggshell. CHEMOSPHERE 2021; 270:128615. [PMID: 33077189 DOI: 10.1016/j.chemosphere.2020.128615] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Revised: 10/07/2020] [Accepted: 10/12/2020] [Indexed: 06/11/2023]
Abstract
This work studied the potential of using eggshell (ES) (200-300 μm) waste as adsorbent for sequential removal of heavy metals, soluble microbial products, and dye wastes. In this study, among soluble microbial products, chicken egg white (CEW) proteins were selected as simulated contaminants. ES was applied to capture heavy metal ions (e.g., Cu2+ and Zn2+) and the formed eggshell metal (ES-M) complex was use to absorb soluble microbial products (e.g., soluble proteins), followed by subsequent removal of dyes from aqueous solutions using ES-M-CEW adsorbent. The experimental conditions for the adsorption of CEW proteins by ES-M include shaking rate, adsorption pH, isothermal and kinetic studies. The maximum protein adsorption by ES-Zn and ES-Cu were 175.67 and 153.65 mg/g, respectively. Optimal removal efficiencies of the ES-M-CEW particles for Acid Orange (AO7) and Toluidine blue (TBO) dyes were at pH 2 and 12, respectively, achieving performance of 75.38 and 114.18 mg/g, respectively. The removal of TBO dye by ES-M-CEW adsorbent was equilibrated at 5 min. The results showed that low cost and simple preparation of the modified ES particles are feasible for treating various wastewaters.
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Affiliation(s)
- Ting-Yang Lin
- Department of Chemical Engineering, Graduate School of Biochemical Engineering, Ming Chi University of Technology, New Taipei City, 243303, Taiwan
| | - Wai Siong Chai
- Department of Chemical Engineering and Environmental Engineering, Faculty of Science and Engineering, University of Nottingham Malaysia Campus, Selangor Darul Ehsan, 43500, Malaysia
| | - Shu-Jen Chen
- Department of Chemical Engineering and Materials Engineering, National Kaohsiung University of Science and Technology, Kaohsiung City, 80778, Taiwan
| | - Jeng-Ywan Shih
- Department of Chemical Engineering, Graduate School of Biochemical Engineering, Ming Chi University of Technology, New Taipei City, 243303, Taiwan
| | - Apurav Krishna Koyande
- Department of Chemical Engineering and Environmental Engineering, Faculty of Science and Engineering, University of Nottingham Malaysia Campus, Selangor Darul Ehsan, 43500, Malaysia
| | - Bing-Lan Liu
- Department of Applied Chemistry, Chaoyang University of Technology, Taichung, 413310, Taiwan.
| | - Yu-Kaung Chang
- Department of Chemical Engineering, Graduate School of Biochemical Engineering, Ming Chi University of Technology, New Taipei City, 243303, Taiwan.
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44
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Xu M, Zhou W, Chen X, Zhou Y, He B, Tan S. Analysis of the biodegradation performance and biofouling in a halophilic MBBR-MBR to improve the treatment of disinfected saline wastewater. CHEMOSPHERE 2021; 269:128716. [PMID: 33121810 PMCID: PMC7578672 DOI: 10.1016/j.chemosphere.2020.128716] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 10/12/2020] [Accepted: 10/20/2020] [Indexed: 05/12/2023]
Abstract
Disinfectant-containing wastewaters have been generated from many places, including marine industries. The synthetic NaClO-containing wastewaters have been effectively treated in a saline MBBR-MBR (moving bed biofilm reactor & membrane bioreactor) system containing marine microorganisms. A low concentration of NaCl (below 100 mg/L) is not enough to kill the microorganisms, but can affect their bioactivity and induce membrane biofouling. A linear relationship has been obtained for the half-life of membrane biofouling as a function of the NaClO concentration (10-100 mg/L): [half-life] = 25-0.12 × [NaClO concentration]. The COD and NH3-N removals are the highest at a salinity of 30 g/L for the marine bioreactors. The behaviour of the typical biofoulants, measured real-timely by fluorescence spectroscopy, can indicate the levels of membrane biofouling and microbial activity, responding to the NaClO and NaCl influences. Based on the behaviour of biofoulants, this work has also proposed a novel strategy of biofoulants monitoring for membrane antifouling, where antifouling responses can be carried out when the concentration of biofoulants significantly increases.
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Affiliation(s)
- Mengchang Xu
- Academician Workstation, Changsha Medical University, Changsha, 410219, China
| | - Wenhu Zhou
- Academician Workstation, Changsha Medical University, Changsha, 410219, China; Xiangya School of Pharmaceutical Sciences, Central South University, Changsha, 410013, China.
| | - Xuncai Chen
- School of Forensic Medicine, Southern Medical University, Guangzhou, 510515, China
| | - Ying Zhou
- Academician Workstation, Changsha Medical University, Changsha, 410219, China
| | - Binsheng He
- Academician Workstation, Changsha Medical University, Changsha, 410219, China
| | - Songwen Tan
- Academician Workstation, Changsha Medical University, Changsha, 410219, China; Xiangya School of Pharmaceutical Sciences, Central South University, Changsha, 410013, China.
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45
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He JY, Zhang HL, Wang H, Hu YQ, Zhang Y. Characteristics of the extracellular products of pure oxygen aerated activated sludge in batch mode. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2021; 83:1946-1957. [PMID: 33905364 DOI: 10.2166/wst.2021.099] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The effects of pure oxygen aeration on compositional characteristics of soluble microbial products (SMP) and extracellular polymeric substances (EPS) of the activated sludge acclimated in a sequential batch reactor (SBR) were explored in batch mode. The structure of the extracellular products would change with different aeration methods or aeration rates. The proportion of SMP of most oxygen aerated sludge was less than 10%, while that in air aerated sludge was as high as 30-40%. The proportion of TB-EPS decreased from 56.95% to 30.63%, and the proportion of LB-EPS increased obviously with the increase of oxygen aeration rate. The contents of the protein (PN) and the polysaccharide (PS) of extracellular products with oxygen aeration were significantly different, and the PN was much higher than PS (p < 0.05). The zeta potential of each component in activated sludge was negative, gradually decreasing with the progress of biological treatment. The fluorescence peaks in SMP, LB-EPS and TB-EPS with pure oxygen aeration were attributed to tryptophan PN-like and humic acid-like fractions. The results showed that the proportion of the components in the extracellular products could be regulated by adjusting the aeration rate and aeration mode, so as to optimize the treatment process of activated sludge.
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Affiliation(s)
- Jia-Ying He
- School of the Environment, Nanjing Normal University, Nanjing 210023, China E-mail: ; † These two authors contributed equally to this paper
| | - Hong-Ling Zhang
- Nanjing Institute of Environmental Science, MEP, Nanjing 210000, China; † These two authors contributed equally to this paper
| | - Hong Wang
- School of the Environment, Nanjing Normal University, Nanjing 210023, China E-mail:
| | - Ya-Qi Hu
- School of the Environment, Nanjing Normal University, Nanjing 210023, China E-mail:
| | - Yong Zhang
- School of the Environment, Nanjing Normal University, Nanjing 210023, China E-mail: ; Key Laboratory of Virtual Geographic Environment (Nanjing Normal University), Ministry of Education, Nanjing 210023, China; State Key Laboratory Cultivation Base of Geographical Environment Evolution (Jiangsu Province), Nanjing 210023, China and Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing 210023, China
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46
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Yang X, Li D, Yu Z, Meng Y, Zheng X, Zhao S, Meng F. Biochemical characteristics and membrane fouling behaviors of soluble microbial products during the lifecycle of Escherichia coli. WATER RESEARCH 2021; 192:116835. [PMID: 33486289 DOI: 10.1016/j.watres.2021.116835] [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: 10/25/2020] [Revised: 01/09/2021] [Accepted: 01/11/2021] [Indexed: 06/12/2023]
Abstract
The complexity of production process and chemical compositions of soluble microbial products (SMPs) largely limits the understanding of membrane fouling in membrane bioreactors (MBRs). Herein, we used a model single-strain Escherichia coli to better understand the chemical natures of SMPs and their roles in membrane fouling. The effects of carbon source and growth phase on the chemical compositions of SMPs were identified at both the compound and molecular levels by using advanced techniques including excitation emission matrix and parallel factor analysis (EEM-PARAFAC), size exclusion chromatography coupled with organic carbon detection (LC-OCD), and untargeted ultra-performance liquid chromatography - Q-Exactive - mass spectrometry (UPLC-Q-Exactive-MS). Subsequently, the roles of SMPs in the propensity of membrane fouling during ultrafiltration (UF) were studied. The results showed that the chemical compositions and fouling potentials of SMPs were carbon source- and growth phase-dependent. In the exponential phase, SMPs mainly consisted of utilization-associated products (UAPs) and remaining substrates. As the microorganism progressed into the stationary and senescent phases, UAPs and biomass-associated products (BAPs) were the main components, respectively. The SMP contents generated in glucose medium were higher than those generated in acetate medium, and higher abundances of humic fluorescent components were observed in glucose-fed SMPs. Van Krevelen diagrams of the UPLC-MS results revealed that acetate-fed SMPs contained more carboxylic-rich alicyclic molecules, peptides-like, aromatic, and carbohydrates-like components than glucose-fed SMPs in the stationary and senescent phases. These components played a significant role in irreversible membrane fouling, as evidenced in UF experiments. Standard blocking and cake filtration were the main fouling mechanisms for the filtration of SMPs collected in the exponential and stationary/senescent phases, respectively. Our findings highlight linkages between SMP compositions and membrane fouling at both the compound and molecular levels and suggest that both the carbon source and growth phase strongly determine the production potential, chemical nature, and fouling behavior of SMPs.
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Affiliation(s)
- Xiaofang Yang
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510006, PR China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Guangzhou 510006, PR China
| | - Danyi Li
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510006, PR China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Guangzhou 510006, PR China
| | - Zhong Yu
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510006, PR China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Guangzhou 510006, PR China
| | - Yabing Meng
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510006, PR China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Guangzhou 510006, PR China
| | - Xing Zheng
- State Key Laboratory of Eco-hydraulics in Northwest Arid Region, Xi'an University of Technology, Shaanxi, 710048, China
| | - Shanshan Zhao
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510006, PR China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Guangzhou 510006, PR China.
| | - Fangang Meng
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510006, PR China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Guangzhou 510006, PR China.
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47
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Smith DS, Nasir R, Parker W, Peters A, Merrington G, van Egmond R, Lofts S. Developing understanding of the fate and behaviour of silver in fresh waters and waste waters. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 757:143648. [PMID: 33316521 DOI: 10.1016/j.scitotenv.2020.143648] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 11/03/2020] [Accepted: 11/03/2020] [Indexed: 06/12/2023]
Abstract
The Windermere Humic Aqueous Model (WHAM) is often used for risk assessment of metals; WHAM can be used to estimate the potential bioavailability of dissolved metals, where metals complexed to dissolved organic matter (DOM) are expected to be less toxic than ionic forms. Silver is a potential metal of concern but WHAM has not been rigorously tested against experimental measurements. This study compares WHAM predictions to measured ionic silver during fixed pH (4, 8 or 10) argentometric titrations of DOM from diverse origins. There were almost two orders of magnitude variation in free silver between sources but, within model uncertainty, WHAM captured this variability. This agreement, between measurements and models, suggests that WHAM is an appropriate tool for silver risk assessment in surface receiving waters when DOM is predominantly in the form of humic/fulvic acids. In sewage samples WHAM dramatically underestimated silver binding by approximately 3 orders of magnitude. Simulations with additional specific strong silver binding sulphide-like binding sites could explain Ag binding at low loadings, but not at higher loadings. This suggests the presence of additional intermediate strength binding sites. These additional ligands would represent components of the raw sewage largely absent in natural waters unimpacted by sewage effluents. A revised empirical model was proposed to account for these sewage-specific binding sites. Further, it is suspected that as sewage organic matter is degraded, either by natural attenuation or by engineered treatment, that sewage organic matter will degrade to a form more readily modelled by WHAM; i.e., humic-like substances. These ageing experiments were performed starting from raw sewage, and the material did in fact become more humic-like, but even after 30 days of aerobic incubation still showed greater Ag+ binding than WHAM predictions. In these incubation experiments it was found that silver (up to 1000 μg/L) had minimal impact on ammonia oxidation kinetics.
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Affiliation(s)
- D Scott Smith
- Department of Chemistry and Biochemistry, Wilfrid Laurier University, Waterloo, ON, Canada.
| | - R Nasir
- Department of Chemistry and Biochemistry, Wilfrid Laurier University, Waterloo, ON, Canada
| | - Wayne Parker
- Department of Civil and Environmental Engineering, University of Waterloo, Waterloo, ON, Canada
| | - A Peters
- WCA Environment Ltd., Brunel House, Faringdon, Oxfordshire, United Kingdom
| | - G Merrington
- WCA Environment Ltd., Brunel House, Faringdon, Oxfordshire, United Kingdom
| | - R van Egmond
- Safety and Environmental Assurance Centre, Unilever, Sharnbrook, Bedfordshire, United Kingdom
| | - S Lofts
- Centre for Ecology and Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster LA1 4AP, United Kingdom
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48
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Burdsall AC, Xing Y, Cooper CW, Harper WF. Bioaerosol emissions from activated sludge basins: Characterization, release, and attenuation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 753:141852. [PMID: 32891995 PMCID: PMC7439818 DOI: 10.1016/j.scitotenv.2020.141852] [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: 06/12/2020] [Revised: 08/15/2020] [Accepted: 08/19/2020] [Indexed: 05/19/2023]
Abstract
This article presents a critical review of the peer-reviewed literature related to bioaerosol generation from activated sludge basins. Characterization techniques include a variety of culture- and nonculture-based techniques, each with unique features. Bioaerosols contain a variety of clinical pathogens including Staphylococcus saprophyticus, Clostridium perfringens, and Salmonella enteritidis; exposure to these microorganisms increases human health risks. Release mechanisms involve splashing and bubble burst dynamics. Larger bubbles emit more aerosol particles than smaller ones. Attenuation strategies include covering sources with lids, adjusting the method and intensity of aeration, and using free-floating carrier media. Future studies should combine culture and non-culture based methods, and expand chemical databases and spectral libraries in order to realize the full power of real-time online monitoring.
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Affiliation(s)
- Adam C Burdsall
- Air Force Institute of Technology, Environmental Engineering and Science Program, Department of Systems Engineering and Management, 2950 Hobson Way, Wright-Patterson AFB, OH 45433, USA
| | - Yun Xing
- Air Force Institute of Technology, Environmental Engineering and Science Program, Department of Systems Engineering and Management, 2950 Hobson Way, Wright-Patterson AFB, OH 45433, USA
| | - Casey W Cooper
- Air Force Institute of Technology, Environmental Engineering and Science Program, Department of Systems Engineering and Management, 2950 Hobson Way, Wright-Patterson AFB, OH 45433, USA
| | - Willie F Harper
- Air Force Institute of Technology, Environmental Engineering and Science Program, Department of Systems Engineering and Management, 2950 Hobson Way, Wright-Patterson AFB, OH 45433, USA.
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Zheng T, Li J, Liu C. Improvement of α-amylase to the metabolism adaptions of soil bacteria against PFOS exposure. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 208:111770. [PMID: 33396088 DOI: 10.1016/j.ecoenv.2020.111770] [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: 09/18/2020] [Revised: 11/10/2020] [Accepted: 12/05/2020] [Indexed: 06/12/2023]
Abstract
Toxicity of perfluoroalkyl substances (PFASs) in soils towards bacteria shows an impact on its ecosystem function. This study aims to obtain insight into the effect of hydrolase (e.g. α-amylase) in soil on metabolism adaptions of bacteria (e.g. Bacillus substilis) against PFOS exposure. Results show that exogenous α-amylase alleviates PFOS toxicity to bacteria growth, disturbance to membrane permeability and stimulation to reactive oxygen species (ROS) production. The mechanisms were owing to that α-amylase strongly influences the strategies of metabolism adaptions of bacteria against PFOS stress. In details, α-amylase prompts bacteria to regulate the secretion of extracellular polymeric substances (EPSs) and the production of metabolic signal (acetic acid), which leads to changes in the physicochemical properties (hydrophilicity, surface charge) of the bacterial surface and the inactivation of the interaction with PFOS, thereby reducing the PFOS toxicity. Molecular simulations show that PFOS combines with Srt A at Gly 53 and Trp 171, which may induce the increase of permeability and changes of surface characteristics. Meanwhile, α-amylase competes with Srt A to bind PFOS at Arg 125 and Lys 176. This competition changes the physicochemical characteristics of PFOS and its bioavailability, further improving the metabolism adaptions of bacteria against PFOS. Altogether, this work provides direct evidences about α-amylase buffering effect of PFOS and demonstrates that the presence of α-amylase affects the essential but complex metabolic response in bacteria triggered by PFOS.
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Affiliation(s)
- Tongtong Zheng
- Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, China-America CRC for Environment & Health of Shandong Province, School of Environmental Science and Engineering, Shandong University, 72# Jimo Binhai Road, Qingdao, Shandong 266237, PR China
| | - Jie Li
- Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, China-America CRC for Environment & Health of Shandong Province, School of Environmental Science and Engineering, Shandong University, 72# Jimo Binhai Road, Qingdao, Shandong 266237, PR China
| | - Chunguang Liu
- Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, China-America CRC for Environment & Health of Shandong Province, School of Environmental Science and Engineering, Shandong University, 72# Jimo Binhai Road, Qingdao, Shandong 266237, PR China; Guangzhou Key Laboratory of Environmental Exposure and Health, School of Environment, Jinan University, PR China.
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50
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Medina SC, Zamora-Vacca N, Luna HJ, Ratkovich N, Rodríguez Susa M. SMP Production in an Anaerobic Submerged Membrane Bioreactor (AnMBR) at Different Organic Loading Rates. MEMBRANES 2020; 10:E317. [PMID: 33142958 PMCID: PMC7692452 DOI: 10.3390/membranes10110317] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Revised: 09/17/2020] [Accepted: 09/18/2020] [Indexed: 11/16/2022]
Abstract
Anaerobic membrane bioreactors (AnMBRs) have demonstrated an excellent capability to treat domestic wastewater. However, biofouling reduces membrane permeability, increasing operational costs and overall energy demand. Soluble microbial products (SMPs) that build up on the membrane surface play a significant role in the biofouling. In this study, the production of SMPs in a 32 L submerged AnMBR operated at three different organic loads (3.0, 4.1 and 1.2 kg chemical oxygen demand (COD)/m3d for phases 1, 2 and 3, respectively) during long-term operation of the reactor (144, 83 and 94 days) were evaluated. The samples were taken from both the permeate and the sludge at three different heights (0.14, 0.44 and 0.75 m). Higher production of SMPs was obtained in phase 2, which was proportional to the membrane fouling. There were no statistically significant differences (p > 0.05) in the SMPs extracted from sludge at different heights among the three phases. In the permeate of phases 1, 2 and 3, the membrane allowed the removal of 56%, 70% and 64% of the SMP concentration in the sludge. SMPs were characterized by molecular weight (MW). A bimodal behavior was obtained, where fractions prevailed with an MW < 1 kDa, associated with SMPs as utilization-associated products (UAPs) caused fouling by the pore-blocking mechanism. The chemical analysis found that, in the SMPs, the unknown COD predominated over the known COD, such as carbohydrates and proteins. These results suggest that further studies in SMP characterization should focus on the unknown COD fraction to understand the membrane fouling in AnMBR systems better.
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Affiliation(s)
- Sandra C. Medina
- Environmental Engineering Research Center (CIIA), Department of Civil and Environmental Engineering, Universidad de Los Andes, Cra. 1 #18a 12, Bogotá 111711, Colombia; (S.C.M.); (H.J.L.); (M.R.S.)
- Water Desalination and Reuse Center (WDRC), Biological and Environmental Science & Engineering (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Nataly Zamora-Vacca
- Environmental Engineering Research Center (CIIA), Department of Civil and Environmental Engineering, Universidad de Los Andes, Cra. 1 #18a 12, Bogotá 111711, Colombia; (S.C.M.); (H.J.L.); (M.R.S.)
- Escuela de Ciencias, Agrícolas, Pecuarias y del Medio Ambiente, Universidad Nacional Abierta y a Distancia, Calle 14 Sur # 23 - 14, Bogotá 551015, Colombia
| | - Hector J. Luna
- Environmental Engineering Research Center (CIIA), Department of Civil and Environmental Engineering, Universidad de Los Andes, Cra. 1 #18a 12, Bogotá 111711, Colombia; (S.C.M.); (H.J.L.); (M.R.S.)
- Facultad de Ingeniería Ambiental, Universidad Antonio Nariño, Calle 22 Sur # 12D - 81, Bogotá 111511, Colombia
| | - Nicolas Ratkovich
- Department of Chemical and Food Engineering, School of Engineering, Universidad de Los Andes, Bogotá 111711, Colombia
| | - Manuel Rodríguez Susa
- Environmental Engineering Research Center (CIIA), Department of Civil and Environmental Engineering, Universidad de Los Andes, Cra. 1 #18a 12, Bogotá 111711, Colombia; (S.C.M.); (H.J.L.); (M.R.S.)
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