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Ekholm J, Persson F, de Blois M, Modin O, Gustavsson DJI, Pronk M, van Loosdrecht MCM, Wilén BM. Microbiome structure and function in parallel full-scale aerobic granular sludge and activated sludge processes. Appl Microbiol Biotechnol 2024; 108:334. [PMID: 38739161 DOI: 10.1007/s00253-024-13165-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Revised: 04/30/2024] [Accepted: 05/01/2024] [Indexed: 05/14/2024]
Abstract
Aerobic granular sludge (AGS) and conventional activated sludge (CAS) are two different biological wastewater treatment processes. AGS consists of self-immobilised microorganisms that are transformed into spherical biofilms, whereas CAS has floccular sludge of lower density. In this study, we investigated the treatment performance and microbiome dynamics of two full-scale AGS reactors and a parallel CAS system at a municipal WWTP in Sweden. Both systems produced low effluent concentrations, with some fluctuations in phosphate and nitrate mainly due to variations in organic substrate availability. The microbial diversity was slightly higher in the AGS, with different dynamics in the microbiome over time. Seasonal periodicity was observed in both sludge types, with a larger shift in the CAS microbiome compared to the AGS. Groups important for reactor function, such as ammonia-oxidising bacteria (AOB), nitrite-oxidising bacteria (NOB), polyphosphate-accumulating organisms (PAOs) and glycogen-accumulating organisms (GAOs), followed similar trends in both systems, with higher relative abundances of PAOs and GAOs in the AGS. However, microbial composition and dynamics differed between the two systems at the genus level. For instance, among PAOs, Tetrasphaera was more prevalent in the AGS, while Dechloromonas was more common in the CAS. Among NOB, Ca. Nitrotoga had a higher relative abundance in the AGS, while Nitrospira was the main nitrifier in the CAS. Furthermore, network analysis revealed the clustering of the various genera within the guilds to modules with different temporal patterns, suggesting functional redundancy in both AGS and CAS. KEY POINTS: • Microbial community succession in parallel full-scale aerobic granular sludge (AGS) and conventional activated sludge (CAS) processes. • Higher periodicity in microbial community structure in CAS compared to in AGS. • Similar functional groups between AGS and CAS but different composition and dynamics at genus level.
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Affiliation(s)
- Jennifer Ekholm
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Sven Hultins Gata 6, 41296, Gothenburg, Sweden
| | - Frank Persson
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Sven Hultins Gata 6, 41296, Gothenburg, Sweden
| | | | - Oskar Modin
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Sven Hultins Gata 6, 41296, Gothenburg, Sweden
| | - David J I Gustavsson
- Sweden Water Research AB, Ideon Science Park, Scheelevägen 15, 22370, Lund, Sweden
- VA SYD, P.O. Box 191, 20121, Malmö, Sweden
| | - Mario Pronk
- Department of Biotechnology, Delft University of Technology, Van Der Maasweg 9, 2629 HZ, Delft, The Netherlands
| | - Mark C M van Loosdrecht
- Department of Biotechnology, Delft University of Technology, Van Der Maasweg 9, 2629 HZ, Delft, The Netherlands
| | - Britt-Marie Wilén
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Sven Hultins Gata 6, 41296, Gothenburg, Sweden.
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2
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Zhao Z, Liu Y, Dong X, Jiang Q, Wang J, Yang X, Chen J, Lei Z. Unveiling the role of ferrous ion in driving microalgae granulation from salt-tolerant strains for mariculture wastewater treatment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 923:171315. [PMID: 38431177 DOI: 10.1016/j.scitotenv.2024.171315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 02/18/2024] [Accepted: 02/25/2024] [Indexed: 03/05/2024]
Abstract
Development of microalgal-bacterial granular sludge (MBGS) from saline-adapted microalgae is a promising approach for efficient mariculture wastewater treatment, whereas the elusive mechanisms governing granulation have impeded its widespread adoption. In this study, spherical and regular MBGS were successfully developed from mixed culture of pure Spirulina platensis and Chlorella sp. GY-H4 at 10 mg/L Fe2+ concentration. The addition of Fe2+ was proven to induce the formation of Fe-precipitates which served as nucleation sites for microbial attachment and granulation initiation. Additionally, Fe2+ increased the prevalence of exopolysaccharide-producing cyanobacteria, i.e. Synechocystis and Leptolyngbya, facilitating microbial cell adhesion. Furthermore, it stimulated the secretion of extracellular proteins (particularly tryptophan and aromatic proteins), which acted as structural backbone for the development of spherical granule form microalgal flocs. Lastly, it fostered the accumulation of exogenous heterotrophic functional genera, resulting in the efficient removal of DOC (98 %), PO43--P (98 %) and NH4+-N (87 %). Nevertheless, inadequate Fe2+ hindered microalgal floc transformation into granules, excessive Fe2+ expanded the anaerobic zone within the granules, almost halved protein content in the TB-EPS, and inhibited the functional genes expression, ultimately leading to an irregular granular morphology and diminished nutrient removal. This research provides valuable insights into the mechanisms by which Fe2+ promotes the granulation of salt-tolerant microalgae, offering guidance for the establishment and stable operation of MBGS systems in mariculture wastewater treatment.
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Affiliation(s)
- Ziwen Zhao
- South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou 510345, China
| | - Yuqi Liu
- South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou 510345, China
| | - Xiaochuan Dong
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Qianrong Jiang
- South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou 510345, China
| | - Jixiang Wang
- Shanghai Academy of Environmental Sciences, Shanghai 200233, China.
| | - Xiaojing Yang
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510006, China.
| | - Jianyu Chen
- South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou 510345, China
| | - Zhongfang Lei
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
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3
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Lin S, Tang W, Xiao Y, Zan F, Liu X, Chen G, Hao T. Sulfur bacteria-reinforced microbial electrochemical denitrification. BIORESOURCE TECHNOLOGY 2024; 393:130121. [PMID: 38029802 DOI: 10.1016/j.biortech.2023.130121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 11/21/2023] [Accepted: 11/26/2023] [Indexed: 12/01/2023]
Abstract
Two limiting factors of microbial electrochemical denitrification (MED) are the abundance and efficiency of the functional microorganisms. To supply these microorganisms, MED systems are inoculated with denitrifying sludge, but such method has much room for improvement. This study compared MED inoculated with autotrophic denitrifying inoculum (ADI) versus with heterotrophic denitrifying inoculum (HDI). ADI exhibited electroactivity for 50% less of timethan HDI. The denitrification efficiency of the ADI biocathode was42% higherthan that of the HDI biocathode. The HDI biocathode had high levels of polysaccharides while the ADI biocathode was rich in proteins, suggesting that two biocathodes may achieveMED but via differentpathways. Microbial communities of two biocathodes indicated MED of HDI biocathode may rely on interspecies electron transfer, whereas sulfur bacteria of ADI biocathode take electrons directly from the cathode to achieve MED. Utilizing autotrophic sulfur-oxidizing denitrifiers, this study offers a strategy for enhancing MED.
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Affiliation(s)
- Sen Lin
- Department of Civil and Environmental Engineering, Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution (Hong Kong Branch) and Water Technology Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau
| | - Wentao Tang
- Department of Civil and Environmental Engineering, Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution (Hong Kong Branch) and Water Technology Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau
| | - Yihang Xiao
- Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau
| | - Feixiang Zan
- School of Environmental Science and Engineering, Low-Carbon Water Environment Technology Center (HUST-SUKE), Key Laboratory of Water and Wastewater Treatment, MOHURD, Huazhong University of Science and Technology, Wuhan, China
| | - Xiaoming Liu
- School of Materials and Environment Engineering, Shenzhen Polytechnic, Shenzhen, China
| | - Guanghao Chen
- Department of Civil and Environmental Engineering, Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution (Hong Kong Branch) and Water Technology Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - Tianwei Hao
- Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau.
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4
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Hao X, Li H, Yuan T, Wu Y. Recovering and potentially applying of alginate like extracellular polymers from anaerobic digested sludge. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 898:165549. [PMID: 37454849 DOI: 10.1016/j.scitotenv.2023.165549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 07/10/2023] [Accepted: 07/13/2023] [Indexed: 07/18/2023]
Abstract
Extracellular polymeric substances (EPS) are biopolymers contained in both aerobic and anaerobic sludge. In EPS, alginate like extracellular polymers (ALE) is thought as a highly valued material, which have been widely studied with aerobic sludge. Nevertheless, a curiosity on ALE remains in anaerobic digested sludge (ADS). With 5 different sludge sources, anaerobic digestion of excess sludge was conducted in a batch mode, and then ADS was used to extract ALE and to analyze its physicochemical properties for potential applications. The yield of ALE extracted from ADS (ALE-ADS) ranged from 119.4 to 179.4 mg/g VSS. The compositional characteristics of ALE-ADS observed by FT-IR, 3D-EEM and UV-Vis spectroscopy revealed that there were minor differences in the composition and property of ALE-ADS but a similarity of 62 %-70 % to a commercial alginate remained in terms of chemical functional groups. Moreover, ALE-ADS composed of 1,4-linked β-d-mannuronic acid (M) and 1,4 α-l-guluronic acid (G) residues that form blocks of GG (20.8 %-33.8 %), MG (12.8 %-30.1 %) and MM (6.6 %-15.1 %), respectively. Based on the gel-forming capacity, film-forming property, adsorbility, and amphiphilicity, ALE-ADS seems potential as a water-proof coating with even a better performance than the commercial alginate, as a seed coating with an increased germination rate, and as a bio-adsorbent with a similar performance to the commercial alginate and ALE from aerobic sludge.
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Affiliation(s)
- Xiaodi Hao
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies, Beijing University of Civil Engineering and Architecture, Beijing 100044, PR China.
| | - Hui Li
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies, Beijing University of Civil Engineering and Architecture, Beijing 100044, PR China
| | - Tugui Yuan
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies, Beijing University of Civil Engineering and Architecture, Beijing 100044, PR China
| | - Yuanyuan Wu
- Beijing Capital Eco-Environment Protection Group Co., Ltd., Beijing 100044, PR China
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5
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Han C, Dai H, Guo Z, Zhu G, Li B, Nawaz Abbasi H, Wang X. Insight into the mechanism of nutrients removal and response regulation of denitrifying phosphorus removal system under calcium ion stress. BIORESOURCE TECHNOLOGY 2023; 388:129747. [PMID: 37717705 DOI: 10.1016/j.biortech.2023.129747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 08/25/2023] [Accepted: 09/06/2023] [Indexed: 09/19/2023]
Abstract
The influent quality is an important factor affecting the nutrients removal and operational stability of denitrifying phosphorus removal (DPR) system. This study investigated the effects of calcium ion (Ca2+) on the nutrients removal, nitrogen oxide (N2O) release, microbial community, and quorum sensing in DPR system. Results showed that high accumulation of Ca2+ had a significant impact on the carbon footprint of DPR system. Specifically, N2O release reached 2.11 mg/L under Ca2+ of 150 mg/L, which represented 214.93% increase compared to 0 mg/L of Ca2+. The DPR system demonstrated its adaptability to elevated Ca2+ concentrations by modifying key enzyme activities involved in nitrogen and phosphorus removal, altering the microbial community structure, and adjusting the type and content of signal molecules. These findings hold significant implications for understanding the stress mechanism of Ca2+ on DPR system, ultimately aiding in the maintenance and enhancement of stable operational performance in biological wastewater treatment process.
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Affiliation(s)
- Cheng Han
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, China
| | - Hongliang Dai
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, China; School of Energy and Environment, Southeast University, Nanjing 210096, China.
| | - Zechong Guo
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, China
| | - Guangcan Zhu
- School of Energy and Environment, Southeast University, Nanjing 210096, China
| | - Bing Li
- Jiangsu Zhongchuang Qingyuan Technology Co., Ltd., Yancheng 224000, China
| | - Haq Nawaz Abbasi
- Department of Environmental Science, Federal Urdu University of Arts, Science and Technology, Karachi, Pakistan.
| | - Xingang Wang
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, China.
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6
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Wang G, Huang X, Wang S, Yang F, Sun S, Yan P, Chen Y, Fang F, Guo J. Effect of food-to-microorganisms ratio on aerobic granular sludge settleability: Microbial community, potential roles and sequential responses of extracellular proteins and polysaccharides. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 345:118814. [PMID: 37591089 DOI: 10.1016/j.jenvman.2023.118814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 07/18/2023] [Accepted: 08/12/2023] [Indexed: 08/19/2023]
Abstract
The food-to-microorganism ratio (F/M) is an important parameter in wastewater biotreatment that significantly affects the granulation and settleability of aerobic granular sludge (AGS). Hence, understanding the long-term effects and internal mechanisms of F/M on AGS settling performance is essential. This study investigated the relationship between F/M and the sludge volume index (SVI) within a range of 0.23-2.50 kgCOD/(kgMLVSS·d). Thiothrix and Candidatus_Competibacter were identified as two dominant bacterial genera influencing AGS settling performance. With F/M increased from 0.27 kgCOD/(kgMLVSS·d) to 1.53 kgCOD/(kgMLVSS·d), the abundance of Thiothrix significantly increased from 0.20% to 27.02%, and the hydrophobicity of extracellular proteins (PN) decreased, which collectively reduced AGS settling performance. However, under high-F/M conditions, the gel-like polysaccharides (PS) effectively retained the granular biomass by binding to the highly abundant Thiothrix (53.65%). The progressive increment in biomass led to a concomitant reduction in F/M, resulting in the recovery of AGS settleability. In addition, two-dimensional correlation infrared spectroscopy analysis revealed the preferential responses of PN and PS to the increase and decrease of F/M, and the content and characteristics of PN and PS played important roles in granular settling. The study provides insight into the microbial composition and the potential role of extracellular polymer substances in the AGS sedimentation behavior, offering valuable theoretical support for stable AGS operation.
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Affiliation(s)
- Gonglei Wang
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Xiaoxiao Huang
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Shuai Wang
- College of Environment Sciences and Engineering, Peking University, Beijing, 100871, China
| | - Fan Yang
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Shiting Sun
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Peng Yan
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Youpeng Chen
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Fang Fang
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China.
| | - Jinsong Guo
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
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7
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Yang B, Liang W, Bin L, Chen W, Chen X, Li P, Wen S, Huang S, Tang B. Insights into the life-cycle of aerobic granular sludge in a continuous flow membrane bioreactor by tracing its heterogeneous properties at different stages. WATER RESEARCH 2023; 243:120419. [PMID: 37536250 DOI: 10.1016/j.watres.2023.120419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 07/24/2023] [Accepted: 07/25/2023] [Indexed: 08/05/2023]
Abstract
This work gave insights into the life-cycle of aerobic granular sludge (AGS) by tracing its heterogeneity in the basic properties at different stages in a closed system (a continuous flow membrane bioreactor, MBR), including physical and chemical characteristics and microbial communities. The results indicate that the entire life-cycle consists of the following four stages, namely, the initial, growing, mature and cleaved stages, where multiple AGS properties synergistically affect the rheological properties of the AGS over its life-cycle. The storage modulus (G') of AGS reached its maximum value at the mature stage, whose value was significantly and positively correlated with the protein (PN) in extracellular polymeric substances (EPS) and granule size, specifically the peak area of granule size distribution, but this value was strongly and negatively correlated with the roughness. The AGS at the mature stage would be more vulnerable to be destroyed than that at other stages under the condition of higher shear strain, such as γ = 50%, which was associated with larger granule size and fewer polysaccharide (PS)-related functional groups (especially in the soluble microbial products (SMPs) in the outermost layer of AGS), and the decrease in PS was correlated with a higher relative abundance of Chloroflexi. Additionally, the value of shear strain that AGS was subjected to had a good linear correlation (R2=0.993) with the Young's modulus, which indicated the ability of AGS to resist deformation improved with increasing values of shear strain.
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Affiliation(s)
- Biao Yang
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, PR China
| | - Weifeng Liang
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, PR China
| | - Liying Bin
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, PR China
| | - Weirui Chen
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, PR China
| | - Xinyi Chen
- Guangdong Guangshen Environmental Protection Technology Co., Ltd., Guangzhou, 510006, PR China
| | - Ping Li
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, PR China
| | - Shanglong Wen
- Guangdong Guangshen Environmental Protection Technology Co., Ltd., Guangzhou, 510006, PR China
| | - Shaosong Huang
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, PR China
| | - Bing Tang
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, PR China.
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8
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Lin Y, Wang Y, Wang W, Hao T, Su K. Mechanistic study on the ferric chloride-based rapid cultivation and enhancement of aerobic granular sludge. ENVIRONMENTAL TECHNOLOGY 2023; 44:3281-3293. [PMID: 35318893 DOI: 10.1080/09593330.2022.2057235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2021] [Accepted: 03/10/2022] [Indexed: 06/14/2023]
Abstract
Aerobic granular sludge (AGS) can achieve simultaneous carbon, nitrogen and phosphorus removal owing to its three-dimensional oxygen gradient structure. However, long start-up period and poor operational stability restrict its application and promotion. A novel rapid granulation strategy, viz., the short-term (7 days) addition of ferric chloride at the commissioning stage, was developed and verified in this study. The granulation period was shortened by 9 days, and the formed granules were compact and dense with an Fe3+ concentration of 250 mg L-1. The addition of flocculant not only maintained a high sludge concentration during the initial stages of granulation (5.3 g L-1), but also stimulated the secretion of TB-EPS and increased protein and polysaccharide contents, thereby expediting granule formation. Additionally, ferric chloride induced a diverse microbial community in granules, resulting in the emergence of new genera, such as Thaurea, Brevundimonas and Kinneretia, which improved pollutant removal performance and flocculent aggregation. The removal efficiencies of COD, PO43--P, and NH4+-N stabilized at 94.2, 62.4, and 71.3%, respectively. Therefore, it has been demonstrated that short-term ferric chloride dosing has a synergistic effect on aerobic granulation.
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Affiliation(s)
- Yuxin Lin
- Department of Civil Engineering, Hefei University of Technology, Hefei, People's Republic of China
- Harbour and Waterway Development Center of Department of Transport of Jiangsu Province, Nanjing, People's Republic of China
| | - Yuyin Wang
- Department of Resources and Environmental Engineering, Hefei University of Technology, Hefei, People's Republic of China
- Civil Engineering, College of Science and Engineering, National University of Ireland, Galway, Ireland
| | - Wei Wang
- Department of Civil Engineering, Hefei University of Technology, Hefei, People's Republic of China
| | - Tianwei Hao
- Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau, People's Republic of China
| | - Kuizu Su
- Department of Civil Engineering, Hefei University of Technology, Hefei, People's Republic of China
- Anhui Provincial Engineering Laboratory for Rural Water Environment and Resources, Hefei, People's Republic of China
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9
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Zahra SA, Purba LDA, Abdullah N, Yuzir A, Iwamoto K, Lei Z, Hermana J. Characteristics of algal-bacterial aerobic granular sludge treating real wastewater: Effects of algal inoculation and alginate-like exopolymers recovery. CHEMOSPHERE 2023; 329:138595. [PMID: 37023906 DOI: 10.1016/j.chemosphere.2023.138595] [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: 12/01/2022] [Revised: 03/16/2023] [Accepted: 04/02/2023] [Indexed: 05/03/2023]
Abstract
Limited information is available on the characteristics of algal-bacterial aerobic granular sludge (AGS) treating real wastewater, especially on its alginate-like exopolymers (ALE) production. In addition, the effect of target microalgae species inoculation on the system performance has not been fully understood. This study aimed to reveal the effect of microalgae inoculation on the characteristics of algal-bacterial AGS and its ALE production potential. Two photo-sequencing batch reactors (PSBR) were employed, namely R1 with activated sludge and R2 with Tetradesmus sp. and activated sludge being inoculated, respectively. Both reactors were fed with locally sourced municipal wastewater and operated for 90 days. Algal-bacterial AGS were successfully cultivated in both reactors. No significant difference was observed between the performances of R1 and R2, reflecting that the inoculation of target microalgae species may not be crucial for the development of algal-bacterial AGS when treating real wastewater. Both reactors achieved an ALE yield of about 70 mg/g of volatile suspended solids (VSS), indicating that a substantial amount of biopolymer can be recovered from wastewater. Interestingly, boron was detected in all the ALE samples, which might contribute to granulation and interspecies quorum sensing. The enrichment of lipids content in ALE from algal-bacterial AGS treating real wastewater reveals its high resource recovery potential. Overall, the algal-bacterial AGS system is a promising biotechnology for simultaneous municipal wastewater treatment and resource (like ALE) recovery.
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Affiliation(s)
- Sasmitha Aulia Zahra
- Department of Chemical and Environmental Engineering, Malaysia-Japan International Institute of Technology (MJIIT), Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, 54100, Kuala Lumpur, Malaysia
| | - Laila Dina Amalia Purba
- Department of Chemical and Environmental Engineering, Malaysia-Japan International Institute of Technology (MJIIT), Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, 54100, Kuala Lumpur, Malaysia
| | - Norhayati Abdullah
- Department of Chemical and Environmental Engineering, Malaysia-Japan International Institute of Technology (MJIIT), Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, 54100, Kuala Lumpur, Malaysia; UTM International, Aras 8, Menara Razak, Jalan Sultan Yahya Petra, 54100, Kuala Lumpur, Malaysia.
| | - Ali Yuzir
- Department of Chemical and Environmental Engineering, Malaysia-Japan International Institute of Technology (MJIIT), Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, 54100, Kuala Lumpur, Malaysia
| | - Koji Iwamoto
- Department of Chemical and Environmental Engineering, Malaysia-Japan International Institute of Technology (MJIIT), Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, 54100, Kuala Lumpur, Malaysia
| | - Zhongfang Lei
- Faculty of Life and Environmental Sciences, University of Tsukuba, Ibaraki, 305-8572, Japan
| | - Joni Hermana
- Department of Environmental Engineering, Faculty of Civil, Planning and Geoengineering, Institut Teknologi Sepuluh Nopember, Surabaya, 60111, Indonesia
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10
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Sethi S, Gupta R, Bharshankh A, Sahu R, Biswas R. Celebrating 50 years of microbial granulation technologies: From canonical wastewater management to bio-product recovery. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 872:162213. [PMID: 36796691 DOI: 10.1016/j.scitotenv.2023.162213] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 01/27/2023] [Accepted: 02/09/2023] [Indexed: 06/18/2023]
Abstract
Microbial granulation technologies (MGT) in wastewater management are widely practised for more than fifty years. MGT can be considered a fine example of human innovativeness-driven nature wherein the manmade forces applied during operational controls in the biological process of wastewater treatment drive the microbial communities to modify their biofilms into granules. Mankind, over the past half a century, has been refining the knowledge of triggering biofilm into granules with some definite success. This review captures the journey of MGT from inception to maturation providing meaningful insights into the process development of MGT-based wastewater management. The full-scale application of MGT-based wastewater management is discussed with an understanding of functional microbial interactions within the granule. The molecular mechanism of granulation through the secretion of extracellular polymeric substances (EPS) and signal molecules is also highlighted in detail. The recent research interest in the recovery of useful bioproducts from the granular EPS is also emphasized.
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Affiliation(s)
- Shradhanjali Sethi
- Academy of Scientific and Innovative Research (AcSIR), CSIR-Human Resource Development Centre (CSIR-HRDC), Ghaziabad, Uttar Pradesh 201002, India; Wastewater Technology Division, CSIR-National Environmental Engineering Research Institute, Nagpur, Maharashtra 440020, India
| | - Rohan Gupta
- Wastewater Technology Division, CSIR-National Environmental Engineering Research Institute, Nagpur, Maharashtra 440020, India
| | - Ankita Bharshankh
- Academy of Scientific and Innovative Research (AcSIR), CSIR-Human Resource Development Centre (CSIR-HRDC), Ghaziabad, Uttar Pradesh 201002, India; Wastewater Technology Division, CSIR-National Environmental Engineering Research Institute, Nagpur, Maharashtra 440020, India
| | - Rojalin Sahu
- Academy of Scientific and Innovative Research (AcSIR), CSIR-Human Resource Development Centre (CSIR-HRDC), Ghaziabad, Uttar Pradesh 201002, India; Wastewater Technology Division, CSIR-National Environmental Engineering Research Institute, Nagpur, Maharashtra 440020, India
| | - Rima Biswas
- Academy of Scientific and Innovative Research (AcSIR), CSIR-Human Resource Development Centre (CSIR-HRDC), Ghaziabad, Uttar Pradesh 201002, India; Wastewater Technology Division, CSIR-National Environmental Engineering Research Institute, Nagpur, Maharashtra 440020, India.
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11
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Chen X, Mai J, Dong X, Wang Q, Li Z, Yuan T, Lei Z, Zhang Z, Shimizu K, Lee DJ. Enhanced alginate-like exopolymers recovery from algal-bacterial aerobic granular sludge: Optimal cultivation condition and contribution of bacteria and microalgae during the transport/storage period. BIORESOURCE TECHNOLOGY 2023; 382:129155. [PMID: 37172746 DOI: 10.1016/j.biortech.2023.129155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 05/01/2023] [Accepted: 05/05/2023] [Indexed: 05/15/2023]
Abstract
Extracting alginate-like exopolymers (ALE) is a promising approach for valuable resources recovery from excess algal-bacterial aerobic granular sludge (AGS) to achieve circular bioeconomy and environmental sustainability in wastewater treatment plants (WWTPs). In this study, six batch cultivation tests were conducted to investigate the optimal cultivation duration or transport/storage period, light intensity, and temperature for algal-bacterial AGS after sampling and before further processing or ALE extraction. At a light intensity of 5 klux, the highest ALE content (36.33 mg/g-VSS) was detected at a low temperature of 10°C, which increased by 300% from its original level after 6-h cultivation. Results from levofloxacin (LVX) exposure and dark condition imply that microalgae contributed more to ALE synthesis in the algal-bacterial granules. This work not only provides a better understanding of the mechanisms involved in ALE biosynthesis but also offers useful guidance for maintaining or improving ALE recovery after algal-bacterial biomass sampling.
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Affiliation(s)
- Xingyu Chen
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Jinfei Mai
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Xiaochuan Dong
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Qian Wang
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266003, China
| | - Zejiao Li
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Tian Yuan
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Zhongfang Lei
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan.
| | - Zhenya Zhang
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Kazuya Shimizu
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan; Faculty of Life Sciences, Toyo University, 1-1-1 Izumino, Oura-gun Itakura, Gunma 374-0193, Japan
| | - Duu-Jong Lee
- Department of Mechanical Engineering, City University of Hong Kong, Kowloon Tang, Hong Kong; Department of Chemical Engineering and Materials Science, Yuan Ze University, Chung-li 32003, Taiwan
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12
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Liu J, Zhang Z, Deng Y, Sato Y, Wu D, Chen G. Coupling methane and bioactive polysaccharide recovery from wasted activated sludge: A sustainable strategy for sludge treatment. WATER RESEARCH 2023; 233:119775. [PMID: 36871381 DOI: 10.1016/j.watres.2023.119775] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 02/19/2023] [Accepted: 02/20/2023] [Indexed: 06/18/2023]
Abstract
Bioactive polysaccharides (PSs) are valuable resources that can be extracted from waste activated sludge (WAS). The PS extraction process causes cell lysis that may enhance hydrolytic processes during anaerobic digestion (AD) and thus increase the methane production. Thus, coupling PSs and methane recovery from WAS could be an efficient and sustainable sludge treatment. In present study, we comprehensively evaluated this novel process from the efficiencies of different coupling strategies, properties of the extracted PSs, and environmental impacts. The results showed that when the PS extraction was before AD, it produced 76.03 ± 2.00 mL of methane per gram of volatile solids (VS) and afforded a PS yield of 6.3 ± 0.09% (w:w), with a PS sulfate content of 13.15% ± 0.06%. In contrast, when PS extraction was after AD, the methane production decreased to 58.14 ± 0.99 mL of methane per gram of VS and afforded a PS yield of 5.67% ± 0.18% (w:w) in VS, with a PS sulfate content of 2.60% ± 0.04%. When there were two PS extractions before and after AD, the methane production, PS yield and sulfate content were 76.03 ± 2.00 mL of methane per gram of VS, 11.54 ± 0.62% and 8.35 ± 0.12%, respectively. Then, the bioactivity of the extracted PSs was assessed by one anti-inflammation assay and three anti-oxidation assays, and statistical analysis revealed that these four bioactivities of PSs were influenced by their sulfate content, protein content and monosaccharide composition, especially the ratios of arabinose and rhamnose. Furthermore, the environmental impact analysis shows that S1 was the best in five environmental indicators compared with other three non-coupled processes. These findings suggest that the coupling PSs and methane recovery process should be further explored to determine its potential for large-scale sludge treatment.
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Affiliation(s)
- Jie Liu
- Department of Civil and Environmental Engineering, Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution (Hong Kong Branch) and Water Technology Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - Zi Zhang
- Department of Civil and Environmental Engineering, Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution (Hong Kong Branch) and Water Technology Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - Yangfan Deng
- Department of Civil and Environmental Engineering, Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution (Hong Kong Branch) and Water Technology Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
| | - Yugo Sato
- Department of Civil and Environmental Engineering, Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution (Hong Kong Branch) and Water Technology Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - Di Wu
- Center for Environmental and Energy Research, Ghent University Global Campus, Republic of Korea
| | - Guanghao Chen
- Department of Civil and Environmental Engineering, Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution (Hong Kong Branch) and Water Technology Center, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China; Wastewater Treatment Laboratory, Fok Ying Tung Graduate School, The Hong Kong University of Science and Technology, Guangzhou, China.
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13
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Hu ZY, Lin YP, Wang QT, Zhang YX, Tang J, Hong SD, Dai K, Wang S, Lu YZ, van Loosdrecht MCM, Wu J, Zeng RJ, Zhang F. Identification and degradation of structural extracellular polymeric substances in waste activated sludge via a polygalacturonate-degrading consortium. WATER RESEARCH 2023; 233:119800. [PMID: 36868117 DOI: 10.1016/j.watres.2023.119800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 02/22/2023] [Accepted: 02/22/2023] [Indexed: 06/18/2023]
Abstract
By maintaining the cell integrity of waste activated sludge (WAS), structural extracellular polymeric substances (St-EPS) resist WAS anaerobic fermentation. This study investigates the occurrence of polygalacturonate in WAS St-EPS by combining chemical and metagenomic analyses that identify ∼22% of the bacteria, including Ferruginibacter and Zoogloea, that are associated with polygalacturonate production using the key enzyme EC 5.1.3.6. A highly active polygalacturonate-degrading consortium (GDC) was enriched and the potential of this GDC for degrading St-EPS and promoting methane production from WAS was investigated. The percentage of St-EPS degradation increased from 47.6% to 85.2% after inoculation with the GDC. Methane production was also increased by up to 2.3 times over a control group, with WAS destruction increasing from 11.5% to 28.4%. Zeta potential and rheological behavior confirmed the positive effect which GDC has on WAS fermentation. The major genus in the GDC was identified as Clostridium (17.1%). Extracellular pectate lyases (EC 4.2.2.2 and 4.2.2.9), excluding polygalacturonase (EC 3.2.1.15), were observed in the metagenome of the GDC and most likely play a core role in St-EPS hydrolysis. Dosing with GDC provides a good biological method for St-EPS degradation and thereby enhances the conversion of WAS to methane.
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Affiliation(s)
- Zhi-Yi Hu
- Engineering Research Center of Soil Remediation of Fujian Province University, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Yi-Peng Lin
- Engineering Research Center of Soil Remediation of Fujian Province University, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Qing-Ting Wang
- Engineering Research Center of Soil Remediation of Fujian Province University, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Yi-Xin Zhang
- Engineering Research Center of Soil Remediation of Fujian Province University, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Jie Tang
- Engineering Research Center of Soil Remediation of Fujian Province University, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Si-Di Hong
- Engineering Research Center of Soil Remediation of Fujian Province University, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Kun Dai
- Engineering Research Center of Soil Remediation of Fujian Province University, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Shuai Wang
- Engineering Research Center of Soil Remediation of Fujian Province University, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Yong-Ze Lu
- School of Energy and Environment, Southeast University, Nanjing 210096, China
| | - Mark C M van Loosdrecht
- Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft, the Netherlands
| | - Jianrong Wu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Raymond Jianxiong Zeng
- Engineering Research Center of Soil Remediation of Fujian Province University, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Fang Zhang
- Engineering Research Center of Soil Remediation of Fujian Province University, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
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14
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Shi C, Zeng RG, Hao LT, Hao XD, Li J. Extracting compositional blocks of alginate-like extracellular polymers (ALE) from conventional activated sludge (CAS). THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 867:161371. [PMID: 36610622 DOI: 10.1016/j.scitotenv.2022.161371] [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: 11/23/2022] [Revised: 12/29/2022] [Accepted: 12/31/2022] [Indexed: 06/17/2023]
Abstract
As a highly added value material, alginate-like extracellular polymers (ALE) can be extracted from extracellular polymeric substances (EPS) from aerobic granular sludge (AGS). In fact, conventional activated sludge (CAS) also contains a certain amount of ALE. As CAS is widely used everywhere, waste activated sludge (WAS) from CAS is huge in its absolute amount. Although the ALE property of CAS was identified not so good as that from AGS, the mechanisms remains unclear. For this reason, it is necessary to unravel the chemically compositional blocks of ALE. Referring to natural alginate, ALE can be separated into three compositional blocks: GGL, GML and MML (like units containing guluronate or mannuronate), associated with other compositions including protein (PN), polysaccharide (PS), phosphorus (P), humic acid (HA). With real WAS from CAS, ALE was extracted and three blocks were separated: GGL = 54 %, GML = 42 % and MML = 4 % in weight, which is similar to the previous study. Moreover, the GGL blocks in CAS were obviously lower than AGS, down to by 1/3-1/2. And the GML and MML blocks in CAS were much higher than AGS, by more than 1/2. Different compositional blocks of ALE in AGS and CAS should be the reason forming different properties in applications. For this reason, a further study will be initiated to dispense/reorganize three blocks of ALE from CAS for expanding its potential applications, based on the compositional blocks of ALE from AGS.
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Affiliation(s)
- Chen Shi
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies, Beijing Advanced Innovation Center for Future Urban Design, Beijing University of Civil Engineering and Architecture, Beijing 100044, PR China
| | - Run-Gen Zeng
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies, Beijing Advanced Innovation Center for Future Urban Design, Beijing University of Civil Engineering and Architecture, Beijing 100044, PR China
| | - Li-Ting Hao
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies, Beijing Advanced Innovation Center for Future Urban Design, Beijing University of Civil Engineering and Architecture, Beijing 100044, PR China
| | - Xiao-Di Hao
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies, Beijing Advanced Innovation Center for Future Urban Design, Beijing University of Civil Engineering and Architecture, Beijing 100044, PR China.
| | - Ji Li
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies, Beijing Advanced Innovation Center for Future Urban Design, Beijing University of Civil Engineering and Architecture, Beijing 100044, PR China
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15
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Sarvajith M, Nancharaiah Y. Properties of alginate-like exopolymers recovered from flocculent and granular microbial sludges of different biological treatment systems treating real municipal wastewater. Sep Purif Technol 2023. [DOI: 10.1016/j.seppur.2023.123460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
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16
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Zhang C, Hu P, Liu Q, Lu Z, Cao B, Tang Y, Hao T. Biopolymer recovery from waste activated sludge toward self-healing mortar crack. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 858:160107. [PMID: 36370773 DOI: 10.1016/j.scitotenv.2022.160107] [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: 09/06/2022] [Revised: 10/28/2022] [Accepted: 11/06/2022] [Indexed: 06/16/2023]
Abstract
Activated sludge (AS) offers great potential for resource recovery considering its high organic and nutrient content. However, low recovery efficiency and high costs are directing the focus toward the high-valuable resource recovery. This study extracted 71.5 ± 5.9 mg/g VSS of alginate-like exopolysaccharides from AS (ALE/AS) and applied it to mortar as a novel biopolymer agent for crack self-healing. With a mortar crack of 120 μm, addition of 0.5 wt% ALE/AS yielded a high crack closure ratio of 86.5 % within 28 days. In comparison to commercial healing agents, marginal flexural strength reduction with ALE/AS addition (17.9 % vs 30.2-50.5 %) was demonstrated. The abundance of COO- group in GG blocks of ALE/AS resulted in a higher cross-link capacity with Ca2+, while the reduction of hydrophilic residues (e.g., COO- and OH) after complexation engendered a lower swelling capacity, which facilitated self-healing and flexural strength maintenance. Molecular dynamics (MD) revealed that lower Ca2+ diffusivity, arising from the stronger electrostatic interactions between the COO- groups and Ca2+, resulted in a high Ca2+ concentration around the cracks, leading to CaCO3 deposition and healed cracks. The outcomes of this study provided light on ALE-based mortar crack healing and presented a possibility for multi-level AS resource recovery.
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Affiliation(s)
- Cong Zhang
- Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau
| | - Peng Hu
- Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau
| | - Qing Liu
- Institute of Applied Physics and Materials Engineering, University of Macau, Macau
| | - Zeyu Lu
- School of Materials Science and Engineering, Southeast University, Nanjing 211189, China
| | - Benyi Cao
- Department of Civil and Environmental Engineering, University of Surrey, Guildford GU2 7XH, United Kingdom
| | - Yuxin Tang
- Institute of Molecule Catalysis and In-Situ/Operando Studies College of Chemistry Fuzhou University, Fuzhou 350116, China
| | - Tianwei Hao
- Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau.
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17
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Dueholm MKD, Besteman M, Zeuner EJ, Riisgaard-Jensen M, Nielsen ME, Vestergaard SZ, Heidelbach S, Bekker NS, Nielsen PH. Genetic potential for exopolysaccharide synthesis in activated sludge bacteria uncovered by genome-resolved metagenomics. WATER RESEARCH 2023; 229:119485. [PMID: 36538841 DOI: 10.1016/j.watres.2022.119485] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 12/08/2022] [Accepted: 12/10/2022] [Indexed: 06/17/2023]
Abstract
A good floc formation of activated sludge (AS) is crucial for solid-liquid separation and production of clean effluent during wastewater treatment. Floc formation is partly controlled by self-produced extracellular polymeric substances (EPS) such as exopolysaccharides, proteins, and nucleic acids. Little is known about the composition, structure, and function of EPS in AS and which bacteria produce them. To address this knowledge gap for the exopolysaccharides, we took advantage of 1083 high-quality metagenome-assembled genomes (MAGs) obtained from 23 Danish wastewater treatment plants. We investigated the genomic potential for exopolysaccharide biosynthesis in bacterial species typical in AS systems based on genome mining and gene synteny analyses. Putative gene clusters associated with the biosynthesis of alginate, cellulose, curdlan, diutan, hyaluronic acids, Pel, poly-β-1,6-N-acetyl-d-glucosamine (PNAG), Psl, S88 capsular polysaccharide, salecan, succinoglycan, and xanthan were identified and linked to individual MAGs, providing a comprehensive overview of the genome-resolved potential for these exopolysaccharides in AS bacteria. The approach and results provide a starting point for a more comprehensive understanding of EPS composition in wastewater treatment systems, which may facilitate a more refined regulation of the activated sludge process for improved stability.
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Affiliation(s)
- Morten Kam Dahl Dueholm
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark.
| | - Maaike Besteman
- Department of Agrotechnology and Food Sciences, Wageningen University & Research, Wageningen, Netherlands
| | - Emil Juel Zeuner
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Marie Riisgaard-Jensen
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Morten Eneberg Nielsen
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Sofie Zacho Vestergaard
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Søren Heidelbach
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Nicolai Sundgaard Bekker
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Per Halkjær Nielsen
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
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18
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An Q, Chen Y, Tang M, Zhao B, Deng S, Li Z. The mechanism of extracellular polymeric substances in the formation of activated sludge flocs. Colloids Surf A Physicochem Eng Asp 2023. [DOI: 10.1016/j.colsurfa.2023.131009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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19
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Kosar S, Isik O, Cicekalan B, Gulhan H, Cingoz S, Yoruk M, Ozgun H, Koyuncu I, van Loosdrecht MCM, Ersahin ME. Coupling high-rate activated sludge process with aerobic granular sludge process for sustainable municipal wastewater treatment. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 325:116549. [PMID: 36419284 DOI: 10.1016/j.jenvman.2022.116549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Revised: 09/28/2022] [Accepted: 10/15/2022] [Indexed: 06/16/2023]
Abstract
Achieving a neutral/positive energy balance without compromising discharge standards is one of the main goals of wastewater treatment plants (WWTPs) in terms of sustainability. Aerobic granular sludge (AGS) technology promises high treatment performance with low energy and footprint requirement. In this study, high-rate activated sludge (HRAS) process was coupled to AGS process as an energy-efficient pre-treatment option in order to increase energy recovery from municipal wastewater and decrease the particulate matter load of AGS process. Three different feeding strategies were applied throughout the study. AGS system was fed with raw municipal wastewater, with the effluent of HRAS process, and with the mixture of the effluent of HRAS process and raw municipal wastewater at Stage 1, Stage 2 and Stage 3, respectively. Total suspended solids (TSS), chemical oxygen demand (COD), ammonia nitrogen (NH4+-N), and total phosphorus (TP) concentrations in the effluent were less than 10 mg/L, 60 mg/L, 0.4 mg/L, and 1.3 mg/L respectively at all stages. Fluctuations were observed in the denitrification performance due to changes in the influent COD/total nitrogen (TN) ratio. This study showed that coupling HRAS process with AGS process by feeding the AGS process with the mixture of HRAS process effluent and raw municipal wastewater could be an appropriate option for both increasing the energy recovery potential of WWTPs and enabling high effluent quality.
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Affiliation(s)
- Sadiye Kosar
- Istanbul Technical University, Civil Engineering Faculty, Environmental Engineering Department, Ayazaga Campus, Maslak, 34469, Istanbul, Turkey.
| | - Onur Isik
- Istanbul Technical University, Civil Engineering Faculty, Environmental Engineering Department, Ayazaga Campus, Maslak, 34469, Istanbul, Turkey; National Research Center on Membrane Technologies, Istanbul Technical University, 34469, Maslak, Istanbul, Turkey; Kahramanmaras Sutcu Imam University, Engineering and Architecture Faculty, Environmental Engineering Department, Onikisubat, 46100, Kahramanmaras, Turkey
| | - Busra Cicekalan
- Istanbul Technical University, Civil Engineering Faculty, Environmental Engineering Department, Ayazaga Campus, Maslak, 34469, Istanbul, Turkey
| | - Hazal Gulhan
- Istanbul Technical University, Civil Engineering Faculty, Environmental Engineering Department, Ayazaga Campus, Maslak, 34469, Istanbul, Turkey
| | - Seyma Cingoz
- ISKI, Istanbul Water and Sewerage Administration, Eyup, 34060, Istanbul, Turkey
| | - Mustafa Yoruk
- ISKI, Istanbul Water and Sewerage Administration, Eyup, 34060, Istanbul, Turkey
| | - Hale Ozgun
- Istanbul Technical University, Civil Engineering Faculty, Environmental Engineering Department, Ayazaga Campus, Maslak, 34469, Istanbul, Turkey; National Research Center on Membrane Technologies, Istanbul Technical University, 34469, Maslak, Istanbul, Turkey
| | - Ismail Koyuncu
- Istanbul Technical University, Civil Engineering Faculty, Environmental Engineering Department, Ayazaga Campus, Maslak, 34469, Istanbul, Turkey; National Research Center on Membrane Technologies, Istanbul Technical University, 34469, Maslak, Istanbul, Turkey
| | - Mark C M van Loosdrecht
- Delft University of Technology, Department of Biotechnology, van der Maasweg 9, 2629, HZ, Delft, the Netherlands
| | - Mustafa Evren Ersahin
- Istanbul Technical University, Civil Engineering Faculty, Environmental Engineering Department, Ayazaga Campus, Maslak, 34469, Istanbul, Turkey; National Research Center on Membrane Technologies, Istanbul Technical University, 34469, Maslak, Istanbul, Turkey
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20
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Cydzik-Kwiatkowska A, Gusiatin MZ, Zielińska M, Wojnowska-Baryła I, Kulikowska D, Bernat K. Alginate-like polymers from full-scale aerobic granular sludge: content, recovery, characterization, and application for cadmium adsorption. Sci Rep 2022; 12:22260. [PMID: 36564508 PMCID: PMC9789099 DOI: 10.1038/s41598-022-26743-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Accepted: 12/20/2022] [Indexed: 12/24/2022] Open
Abstract
Aerobic granular sludge (AGS) is a proven resource for the recovery of biopolymers like alginate-like polymers (ALP). This is the first report on the dynamics of ALP produced by AGS (ALP-AGS) in a full-scale wastewater treatment plant (WWTP), optimization of ALP recovery from AGS, and adsorption of cadmium (Cd2+) by ALP. Recovery of ALP was highest when using 120 mL of 0.2 M Na2CO3 at 70 °C for 45 min. Seasonal (1.5 years, over 3100 cycles) and intra-cycle changes in ALP-AGS in the WWTP were monitored. The ALP content in AGS increased in the transition period between winter and spring, reaching over 150 mg/g MLSS. In the batch reactor cycle, the ALP-AGS level peaked 2 h after the start of aeration (mean peak level: 120 mg/g MLSS), then decreased about two-fold by the end of the cycle. The ALP-AGS had a small surface area and a lamellar structure with crystalline outgrowths. The optimal conditions of Cd2+ adsorption with ALP were a dosage of 7.9 g d.m./L, a pH of 4-8, and an equilibrium time of 60 min. Carboxyl and hydroxyl groups were the key functional groups involved in Cd2+ adsorption. According to the Sips model, the maximum Cd2+ adsorption capacity of ALP-AGS was 29.5 mg/g d.m., which is similar to that of commercial alginate. AGS is a richer source of ALP than activated sludge, which ensures the cost-effectiveness of ALP recovery and increases the sustainability of wastewater treatment. Information on the chemical properties and yields of ALP from full-scale WWTPs is important for downstream applications with the recovered ALP.
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Affiliation(s)
- Agnieszka Cydzik-Kwiatkowska
- grid.412607.60000 0001 2149 6795Department of Environmental Biotechnology, Faculty of Geoengineering, University of Warmia and Mazury in Olsztyn, Słoneczna St. 45G, 10-709 Olsztyn, Poland
| | - Mariusz Z. Gusiatin
- grid.412607.60000 0001 2149 6795Department of Environmental Biotechnology, Faculty of Geoengineering, University of Warmia and Mazury in Olsztyn, Słoneczna St. 45G, 10-709 Olsztyn, Poland
| | - Magdalena Zielińska
- grid.412607.60000 0001 2149 6795Department of Environmental Biotechnology, Faculty of Geoengineering, University of Warmia and Mazury in Olsztyn, Słoneczna St. 45G, 10-709 Olsztyn, Poland
| | - Irena Wojnowska-Baryła
- grid.412607.60000 0001 2149 6795Department of Environmental Biotechnology, Faculty of Geoengineering, University of Warmia and Mazury in Olsztyn, Słoneczna St. 45G, 10-709 Olsztyn, Poland
| | - Dorota Kulikowska
- grid.412607.60000 0001 2149 6795Department of Environmental Biotechnology, Faculty of Geoengineering, University of Warmia and Mazury in Olsztyn, Słoneczna St. 45G, 10-709 Olsztyn, Poland
| | - Katarzyna Bernat
- grid.412607.60000 0001 2149 6795Department of Environmental Biotechnology, Faculty of Geoengineering, University of Warmia and Mazury in Olsztyn, Słoneczna St. 45G, 10-709 Olsztyn, Poland
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21
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Campo R, Carretti E, Lubello C, Lotti T. Recovery of structural extracellular polymeric substances (sEPS) from aerobic granular sludge: Insights on biopolymers characterization and hydrogel properties for potential applications. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 324:116247. [PMID: 36174471 DOI: 10.1016/j.jenvman.2022.116247] [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: 06/21/2022] [Revised: 09/07/2022] [Accepted: 09/09/2022] [Indexed: 06/16/2023]
Abstract
Nowadays, wastewater treatment plants (WWTPs) are transforming into water resource recovery facilities (WRRFs) where the resource recovery from waste streams is pivotal. Aerobic granular sludge (AGS) is a novel technology applied for wastewater treatment. Extracellular polymeric substances (EPS) secreted by microorganisms promote the aggregation of bacterial cells into AGS and the structural fraction of EPS (sEPS) is responsible for the mechanical properties of AGS. sEPS can be extracted and recovered from waste AGS by physico-chemical methods and its characterization is to date of relevant concern to understand the properties in the perspective of potential applications. This study reports on: characterization of sEPS extracted and recovered from AGS; - formation and characterization of sEPS-based hydrogels. Briefly, sEPS were extracted by a thermo-alkaline process followed by an acidic precipitation. sEPS-based hydrogels were formed by a cross-linking process with a 2.5% w/w CaCl2 solution. The following key-findings can be drawn: i) hydrogels can be formed starting from 1% w/w sEPS on, by diffusion of Ca2+ into sEPS network; ii) the Ca/C molar ratio of hydrogels decreased with increasing concentration of sEPS from 1 to 10% w/w; iii) the thermogravimetric and spectroscopic behaviours of sEPS show that the cross-linking reaction mainly involves the polysaccharidic fraction of biopolymers; iv) water-holding capacity up to 99 gH2O/gsEPS was registered for 1% w/w sEPS-based hydrogels, suggesting applications in several industrial sectors (i.e. chemical, paper, textile, agronomic, etc.); v) rheological results highlighted a solid-like behaviour (G'≫G") of sEPS-based hydrogels. The power-law fitting of G' vs. sEPS concentration suggests that the expansion of the sEPS network during cross-linking occurs through a percolative mechanism involving the initial formation of sEPS oligomers clusters followed by their interconnection towards the formation of 3D network. These findings provide additional information about the mechanisms of sEPS-based hydrogel formation and reveal the peculiar physico-chemical characteristics of sEPS which nowadays are increasingly gaining interest in the context of resource recovery.
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Affiliation(s)
- Riccardo Campo
- Department of Civil and Environmental Engineering - (DICEA), University of Florence, Florence, Italy.
| | - Emiliano Carretti
- Department of Chemistry "Ugo Schiff" & CSGI Consortium, University of Florence, Italy
| | - Claudio Lubello
- Department of Civil and Environmental Engineering - (DICEA), University of Florence, Florence, Italy
| | - Tommaso Lotti
- Department of Civil and Environmental Engineering - (DICEA), University of Florence, Florence, Italy
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22
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Ni L, Wang K, Wang Z, Wang Y. Antibiofouling Characteristics and Mechanisms in an Anammox Membrane Bioreactor Based on an Optimized Photocatalytic Technology─Photocatalytic Optical Fibers. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:16144-16155. [PMID: 36269937 DOI: 10.1021/acs.est.2c04023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
As an ecofriendly photocatalytic antifouling technology for membrane bioreactors (MBRs), photocatalytic optical fibers (POFs) can decrease the replacement cost of modified membranes and prevent the proliferation of photosynthetic bacteria caused by direct light illumination. Here, POFs were applied in situ in an anaerobic ammonium oxidation (anammox) MBR for membrane biofouling control. Compared with the control MBR without POFs treatment, the average fouling cycle of the POFs-loaded MBR was extended by 137%, and the energy consumption caused by membrane fouling was saved by 18%. In the antibiofouling process, •OH was the key photocatalytic reactive species. On the fouled POFs-loaded membranes, the membrane-adhered foulant was significantly decreased by photocatalytic degradation of the proteins, polysaccharides and humic substances in the microbial metabolites. The membrane-attached bacteria were inactivated by the POFs by the mechanisms of cell-membrane destruction and cell-membrane permeabilization, which caused bacterial necrosis and apoptosis, respectively. Moreover, the total nitrogen-removal efficiencies of the two MBRs were maintained at 85.3-90.4%, and the abundance of anammox bacteria increased from 21.3% to 46.2% during the 202 days of operation, indicating an efficient anammox process with excellent nitrogen-removal performance, biomass retention, and anammox bacteria enrichment. The systematic insights into the antibiofouling performance and mechanisms of POFs in anammox MBRs will promote application and development of membrane-filtration technology in wastewater treatment using environmentally friendly and energy-efficient antifouling strategies.
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Affiliation(s)
- Lingfeng Ni
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai200092, P. R. China
- Shanghai Institute of Pollution Control and Ecological Security, Siping Road, Shanghai200092, P. R. China
| | - Kaichong Wang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai200092, P. R. China
- Shanghai Institute of Pollution Control and Ecological Security, Siping Road, Shanghai200092, P. R. China
| | - Zhiwei Wang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai200092, P. R. China
- Shanghai Institute of Pollution Control and Ecological Security, Siping Road, Shanghai200092, P. R. China
| | - Yayi Wang
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai200092, P. R. China
- Shanghai Institute of Pollution Control and Ecological Security, Siping Road, Shanghai200092, P. R. China
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23
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Chen X, Lee YJ, Yuan T, Lei Z, Adachi Y, Zhang Z, Lin Y, van Loosdrecht MCM. A review on recovery of extracellular biopolymers from flocculent and granular activated sludges: Cognition, key influencing factors, applications, and challenges. BIORESOURCE TECHNOLOGY 2022; 363:127854. [PMID: 36067889 DOI: 10.1016/j.biortech.2022.127854] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 08/21/2022] [Accepted: 08/22/2022] [Indexed: 06/15/2023]
Abstract
A reasonable recovery of excess sludge may shift the waste into wealth. Recently an increasing attention has been paid to the recycling of extracellular biopolymers from conventional and advanced biological wastewater treatment systems such as flocculent activated sludge (AS), bacterial aerobic granular sludge (AGS), and algal-bacterial AGS processes. This review provides the first overview of current research developments and future directions in the recovery and utilization of high value-added biopolymers from the three types of sludge. It details the discussion on the recent evolvement of cognition or updated knowledge on functional extracellular biopolymers, as well as a comprehensive summary of the operating conditions and wastewater parameters influencing the yield, quality, and functionality of alginate-like exopolymer (ALE). In addition, recent attempts for potential practical applications of extracellular biopolymers are discussed, suggesting research priorities for overcoming identification challenges and future prospects.
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Affiliation(s)
- Xingyu Chen
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Yu-Jen Lee
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Tian Yuan
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Zhongfang Lei
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan.
| | - Yasuhisa Adachi
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Zhenya Zhang
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Yuemei Lin
- Department of Biotechnology, Delft University of Technology, van der Maasweg 9, 2629 HZ, Delft, the Netherlands
| | - Mark C M van Loosdrecht
- Department of Biotechnology, Delft University of Technology, van der Maasweg 9, 2629 HZ, Delft, the Netherlands
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24
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Zhang P, Zou K, Yuan L, Liu J, Liu B, Qing TP, Feng B. A biomass resource strategy for alginate-polyvinyl alcohol double network hydrogels and their adsorption to heavy metals. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.122050] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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25
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Weng X, Mao Z, Fu HM, Chen YP, Guo JS, Fang F, Xu XW, Yan P. Biofilm formation during wastewater treatment: Motility and physiological response of aerobic denitrifying bacteria under ammonia stress based on surface plasmon resonance imaging. BIORESOURCE TECHNOLOGY 2022; 361:127712. [PMID: 35908635 DOI: 10.1016/j.biortech.2022.127712] [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: 06/23/2022] [Revised: 07/24/2022] [Accepted: 07/26/2022] [Indexed: 06/15/2023]
Abstract
A bacterial image analysis system based on surface plasmon resonance imaging was established to investigate the effect of bacterial motility on biofilm formation under high ammonia nitrogen at the single-cell level. The results showed that the bacterial mean rotation speed and vertical motility distance decreased with the increasing concentration of ammonia nitrogen. Ammonia nitrogen inhibited the metabolic activity of the bacteria, decreasing bacterial motility. Bacterial motility was negatively correlated with the biofilm-formation ability. The biofilm formation ability of Enterobacter cloacae strain HNR exposed to ammonia nitrogen was enhanced by reducing its movement and promoting EPS secretion. Genes related to the tricarboxylic acid cycle and oxidative phosphorylation were down-regulated, indicating inhibition of microbial energy metabolism. Genes related to bacterial secretion and lipopolysaccharide synthesis were up-regulated, facilitating the formation of biofilms and enabling the bacteria to resist ammonia nitrogen stress. This study provides new insights into the biofilm formation under ammonia stress.
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Affiliation(s)
- Xun Weng
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China; College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Zheng Mao
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China; College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Hui-Min Fu
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China; College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - You-Peng Chen
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China; College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Jin-Song Guo
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China; College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Fang Fang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China; College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Xiao-Wei Xu
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China; College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Peng Yan
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China; College of Environment and Ecology, Chongqing University, Chongqing 400045, China.
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26
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Wang H, Wu P, Zheng D, Deng L, Wang W. N-Acyl-Homoserine Lactone (AHL)-Mediated Microalgal-Bacterial Communication Driving Chlorella-Activated Sludge Bacterial Biofloc Formation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:12645-12655. [PMID: 35881886 DOI: 10.1021/acs.est.2c00905] [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] [Indexed: 06/15/2023]
Abstract
N-acyl-homoserine lactones (AHLs) as autoinducers of Gram-negative bacteria for quorum sensing regulation have shown positive effects on the production of aromatic proteins in extracellular polymeric substances (EPSs) during bioflocculation. To investigate the role of AHLs in aromatic protein production, a Chlorella-bacteria system with great bioflocculation was established via fed-batch cultivation. Tryptophan and aromatic proteins as the main compounds in the EPS of bioflocs showed an increasing trend during fed-batch cultivation. The Chlorella cells only secreted tryptophan rather than aromatic proteins during axenic cultivation. N-dodecanoyl-l-homoserine lactone (C12-HSL) was correlated with the flocculation activity and extracellular protein content of bioflocs during fed-batch cultivation. The addition of exogenous C12-HSL enhanced the flocculation activity of the Chlorella-bacteria system and aromatic protein production in the EPS. Chlorella cells sensed exogenous C12-HSL and significantly upregulated the aromatic protein synthesis pathway during axenic cultivation. In addition, vanillin as a quorum-sensing inhibitor suppressed the positive effect of C12-HSL on flocculation activity and aromatic protein production and synthesis. This result indicated that vanillin intercepts the response of Chlorella cells to C12-HSL. Overall, C12-HSL is supposed to be an important signal molecule to achieve communication between Chlorella and Gram-negative bacteria and subsequently induce Chlorella cells to produce aromatic proteins for biofloc formation.
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Affiliation(s)
- Hong Wang
- Biogas Institute of Ministry of Agriculture and Rural Affairs, Chengdu 610041, China
- Key Laboratory of Development and Application of Rural Renewable Energy, Ministry of Agriculture and Rural Affairs, Chengdu 610041, China
- Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu 610213, China
| | - Peike Wu
- Biogas Institute of Ministry of Agriculture and Rural Affairs, Chengdu 610041, China
- Key Laboratory of Development and Application of Rural Renewable Energy, Ministry of Agriculture and Rural Affairs, Chengdu 610041, China
| | - Dan Zheng
- Biogas Institute of Ministry of Agriculture and Rural Affairs, Chengdu 610041, China
- Key Laboratory of Development and Application of Rural Renewable Energy, Ministry of Agriculture and Rural Affairs, Chengdu 610041, China
| | - Liangwei Deng
- Biogas Institute of Ministry of Agriculture and Rural Affairs, Chengdu 610041, China
- Key Laboratory of Development and Application of Rural Renewable Energy, Ministry of Agriculture and Rural Affairs, Chengdu 610041, China
| | - Wenguo Wang
- Biogas Institute of Ministry of Agriculture and Rural Affairs, Chengdu 610041, China
- Key Laboratory of Development and Application of Rural Renewable Energy, Ministry of Agriculture and Rural Affairs, Chengdu 610041, China
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27
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Li J, Hao X, Gan W, van Loosdrecht MCM, Wu Y. Enhancing extraction of alginate like extracellular polymers (ALE) from flocculent sludge by surfactants. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 837:155673. [PMID: 35508248 DOI: 10.1016/j.scitotenv.2022.155673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 04/29/2022] [Accepted: 04/29/2022] [Indexed: 06/14/2023]
Abstract
Alginate like extracellular polymers (ALE) recovered from flocculent sludge has been identified as a kind of highly valuable biomaterials. However, the extraction protocols limit the production of biopolymers as ALE extracted from flocculent sludge is at a lower level, around 90-190 mg/g VSS. Under this circumstance, the eco-friendly and effective optimizations for the ALE extraction protocols are expected, and thus surfactants have gained an attention to enhancing the ALE extraction. With this study, different surfactants with different structures and chemical characteristics, such as sodium dodecyl sulfate (SDS), cetyltrimethylammonium bromide (CTAB) and octyl phenyl polyoxyethylene ether (Triton X-100), were experimented to improve the ALE extraction, and in turn the optimal conditions and the associated mechanisms were evaluated and figured out. The experimental results indicated that surfactants could enhance the ALE extraction but also improve the alginate purification of ALE. With the optimal dosage of surfactants, the ALE extraction increased from 124.1 mg/g VSS to about 222.8-281.9 mg/g VSS, and the alginate purify was at around 54%-70%, in which the efficiency of the ALE extraction was improved by 79.5%-127.2%. Among others, Triton X-100 had the best performance on improving the ALE extraction, followed by CTAB and SDS. The mechanisms of surfactants on enhancing the ALE extraction and improving the alginate purify can be attributed to: i) surfactants micelles, which can solubilize flocs and extracellular biopolymers; ii) similar structures of surfactants and ALE, which follows the rule of "like dissolves like"; iii) functional groups adsorption, which facilitates the ALE release from matrixes. In a word, the optimized extraction protocol by using surfactants can be effectively applied to extract ALE from flocculent sludge.
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Affiliation(s)
- Ji Li
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies/Beijing Advanced Innovation Centre of Future Urban Design, Beijing University of Civil Engineering & Architecture, Beijing 100044, PR China
| | - Xiaodi Hao
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies/Beijing Advanced Innovation Centre of Future Urban Design, Beijing University of Civil Engineering & Architecture, Beijing 100044, PR China.
| | - Wei Gan
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies/Beijing Advanced Innovation Centre of Future Urban Design, Beijing University of Civil Engineering & Architecture, Beijing 100044, PR China
| | - Mark C M van Loosdrecht
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies/Beijing Advanced Innovation Centre of Future Urban Design, Beijing University of Civil Engineering & Architecture, Beijing 100044, PR China; Dept. of Biotechnology, Delft University of Technology, van der Maasweg 9, 2629 HZ Delft, the Netherlands
| | - Yuanyuan Wu
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies/Beijing Advanced Innovation Centre of Future Urban Design, Beijing University of Civil Engineering & Architecture, Beijing 100044, PR China
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28
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Zhang P, Yuan L, Zeng J, Zou K, Liu B, Qing T, Feng B. Alginate production of Pseudomonas strains and its application in preparation of alginate-biomass hydrogel for heavy metal adsorption. Int J Biol Macromol 2022; 222:1511-1521. [DOI: 10.1016/j.ijbiomac.2022.09.252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 09/21/2022] [Accepted: 09/27/2022] [Indexed: 11/29/2022]
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29
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Chen X, Wang J, Wang Q, Li Z, Yuan T, Lei Z, Zhang Z, Shimizu K, Lee DJ. A comparative study on simultaneous recovery of phosphorus and alginate-like exopolymers from bacterial and algal-bacterial aerobic granular sludges: Effects of organic loading rate. BIORESOURCE TECHNOLOGY 2022; 357:127343. [PMID: 35605775 DOI: 10.1016/j.biortech.2022.127343] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 05/15/2022] [Accepted: 05/17/2022] [Indexed: 06/15/2023]
Abstract
The effects of organic loading rate (OLR) on simultaneous phosphorus (P) and alginate-like exopolymers (ALE) recovery from bacterial aerobic granular sludge (AGS) and algal-bacterial AGS were examined and compared during 70 days' operation. With the increase of OLR (0.6-1.2 g COD/(L·day)), both AGS showed good settleability and granular strength with P bioavailability > 92% (Stage III). The moderate increase in OLR had a positive influence on simultaneous recovery of P and ALE. On day 60, the contents of ALE and guluronic acid/guluronic acid (GG) blocks reached the highest in algal-bacterial AGS, about 13.37 and 2.13 mg/g-volatile suspended solids (VSS), respectively. Meanwhile, about daily 0.55 kg of P is estimated to be recovered from the wastewater treatment plant with a treatment capacity of 10,000 m3/day. P mass balance analysis during ALE extraction from both AGS was conducive to further evaluation of P removal pathway and its application potentials.
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Affiliation(s)
- Xingyu Chen
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Jixiang Wang
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Qian Wang
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Zejiao Li
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Tian Yuan
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Zhongfang Lei
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan.
| | - Zhenya Zhang
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Kazuya Shimizu
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Duu-Jong Lee
- Department of Chemical Engineering, National Taiwan University, Taipei 106, Taiwan; Department of Mechanical Engineering, City University of Hong Kong, Kowloon Tang, Hong Kong
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30
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Liu M, Meng P, Chen G, Guan Y, Liu G. Correlation of structural extracellular polymeric substances in the mesh biofilms with solids retention time and biofilm hydraulic resistance in dynamic membrane bioreactors. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 832:155000. [PMID: 35381253 DOI: 10.1016/j.scitotenv.2022.155000] [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: 02/18/2022] [Revised: 03/19/2022] [Accepted: 03/30/2022] [Indexed: 06/14/2023]
Abstract
Dynamic membrane bioreactor (DMBR), which mainly relied on the in-situ formed biofilms on support materials with large aperture (e.g., nylon mesh) to separate fine particles in wastewater, has attracted a lot of attentions due to low cost. The filtration performance of DMBR is mainly determined by the structure and hydraulic resistance of biofilms formed on the mesh. Therefore, understanding the correlation of operation conditions with mesh biofilm compositions and permeability are critically important for optimizing DMBR operation. In present study, how structural extracellular polymeric substances, including alginate-like extracellular polysaccharide (ALE) and amyloid-like protein (AP), in mesh biofilms correlate to solids retention time (SRT) and biofilm structures was explored in DMBRs. At 5d-SRT, compact and gel-like mesh biofilms were formed with a high specific filtration resistance (SFR) of 459 × 109 m/g, while at 40d-SRT porous mesh biofilms were developed with a low SFR of 24 × 109 m/g. Consequently, the 5d-SRT MBR experienced more rapid rise in transmembrane pressure. Further studies found that the 5d-SRT mesh biofilms had a higher AP content, which was positively correlated to biofilm hydraulic resistance. On the contrary, the 40d-SRT mesh biofilms contained a higher content of ALE, suggesting that ALE was negatively correlated to biofilm hydraulic resistance. Therefore, AP instead of ALE likely played a more important role in the formation of compact and gel-like mesh biofilms.
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Affiliation(s)
- Mai Liu
- School of Environment, Guangdong Engineering Research Center of Water Treatment Processes and Materials, Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 510632, China
| | - Peipei Meng
- School of Environment, Guangdong Engineering Research Center of Water Treatment Processes and Materials, Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 510632, China
| | - Guichang Chen
- School of Environment, Guangdong Engineering Research Center of Water Treatment Processes and Materials, Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 510632, China
| | - Ying Guan
- Department of Biostatistics, School of Public Health, Southern Medical University, Guangzhou 510515, China.
| | - Guoqiang Liu
- School of Environment, Guangdong Engineering Research Center of Water Treatment Processes and Materials, Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 510632, China.
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31
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Melo A, Quintelas C, Ferreira EC, Mesquita DP. The Role of Extracellular Polymeric Substances in Micropollutant Removal. FRONTIERS IN CHEMICAL ENGINEERING 2022. [DOI: 10.3389/fceng.2022.778469] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
In biological wastewater treatment (WWT), microorganisms live and grow held together by a slime matrix comprised of extracellular polymeric substances (EPS), forming a three-dimensional microbial structure of aggregates (flocs or granules) and by chemical binding forces. Furthermore, microscopic observations showed that microbial cells within the flocs were cross linked with EPS, forming a network of polymers with pores and channels. The EPS are typically composed of organic substances such as polysaccharides (PS), proteins (PNs), humic acid substances (HAS), nucleic acids, and lipids. It has been established that EPS play an essential role in aggregate flocculation, settling, and dewatering. Moreover, in the presence of toxic substances, such as pharmaceutical compounds and pesticides, EPS form a protective layer for the aggregated biomass against environmental disturbances that might play an important role in the transport and transformation of micropollutants. Some researchers indicated that there is an increase in EPS concentration under toxic conditions, which can induce an increase in the size of microbial aggregates. In this contribution, we critically review the available information on the impact of micropollutants on microbial EPS production and the relationship between EPS and microbial aggregate structure. Also, a general definition, composition, and factors that affect EPS production are presented.
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32
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Ran X, Zhou M, Wang T, Wang W, Kumari S, Wang Y. Multidisciplinary characterization of nitrogen-removal granular sludge: A review of advances and technologies. WATER RESEARCH 2022; 214:118214. [PMID: 35240472 DOI: 10.1016/j.watres.2022.118214] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 02/15/2022] [Accepted: 02/18/2022] [Indexed: 06/14/2023]
Abstract
Nitrogen-removal granular sludge (NRGS) is a promising technology in wastewater treatment, with advantages of efficient nitrogen removal, less footprint, lower sludge production and energy consumption, and is a way for wastewater treatment plants to achieve carbon-neutrality. Aerobic granular sludge (AGS) and anammox granular sludge (AnGS) are two typical NRGS technologies that have attracted extensive attention. Mounting evidence has shown strong associations between NRGS properties and the status of NRGS systems; however, a holistic view is still missing. The aim of this article is to provide an overview of NRGS with an emphasis on characterization. Specifically, the integrated nitrogen transformation pathways inside NRGS and the performance of NRGS treating various wastewaters are discussed. NRGS properties are categorized as physical-, chemical-, biological- and systematical ones, presenting current advances and corresponding characterization technologies. Finally, the future prospects for furthering the mechanistic understanding and engineering application of NRGS are proposed. Overall, the technological advancements in characterization have greatly contributed to understanding NRGS properties, which are potential factors for optimizing the performance and evaluating the working status of NRGS. This review will provide guidance in characterizing NRGS properties and boost the introduction of novel characterization technologies.
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Affiliation(s)
- Xiaochuan Ran
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, China
| | - Mingda Zhou
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, China
| | - Tong Wang
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, China
| | - Weigang Wang
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, China
| | - Sheena Kumari
- Institute for Water and Wastewater Technology, Durban University of Technology, P.O. Box 1334, Durban 4000, South Africa
| | - Yayi Wang
- State Key Laboratory of Pollution Control and Resources Reuse, Shanghai Institute of Pollution Control and Ecological Security, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, China.
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Qiu B, Liao G, Wu C, Dai C, Bin L, Gao X, Zhao Y, Li P, Huang S, Fu F, Tang B. Rapid granulation of aerobic granular sludge and maintaining its stability by combining the effects of multi-ionic matrix and bio-carrier in a continuous-flow membrane bioreactor. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 813:152644. [PMID: 34968611 DOI: 10.1016/j.scitotenv.2021.152644] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 12/07/2021] [Accepted: 12/19/2021] [Indexed: 06/14/2023]
Abstract
The present investigation aimed at providing a novel approach to promote the rapid granulation and stability of aerobic granular sludge (AGS) in a continuous-flow membrane bioreactor (MBR). By operating two identical MBRs with or with no bio-carrier for 125 days, it was found that the combination of multi-ionic matrix and bio-carrier could promote the rapid formation and maintain the long-term stability of AGS. The primary AGS was first observed inside the reactor on day 14, and the mature AGS appeared soon and kept stable for more than 4 months (its average size still was about 800 μm on day 125). Suitable filling ratio of bio-carrier was beneficial to form a stable and regular circulating water flow inside, and adding divalent metal ions quickly reduced the negative charges of tiny sludge particles, which were two essential factors leading to the rapid granulation of AGS and maintaining its stability. The multi-ionic matrix not only enhanced the biological aggregation process, but also facilitated the expansion of the cultivated AGS into a new multi-habitat system of Mn-AGS, in which, complex microbial communities with rich bio-diversity robustly promoted the efficient removal of organic pollutants and nutrients.
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Affiliation(s)
- Bangqiao Qiu
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou Key Laboratory Environmental Catalysis and Pollution Control, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Guangzhou 510006, PR China
| | - Guohao Liao
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou Key Laboratory Environmental Catalysis and Pollution Control, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Guangzhou 510006, PR China
| | - Chuandong Wu
- Guangdong Yuehai Water Investment Co., Ltd., Shenzhen 518021, PR China
| | - Chencheng Dai
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou Key Laboratory Environmental Catalysis and Pollution Control, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Guangzhou 510006, PR China
| | - Liying Bin
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou Key Laboratory Environmental Catalysis and Pollution Control, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Guangzhou 510006, PR China
| | - Xinlei Gao
- Guangdong Yuehai Water Investment Co., Ltd., Shenzhen 518021, PR China
| | - Yan Zhao
- Guangdong Yuehai Water Investment Co., Ltd., Shenzhen 518021, PR China
| | - Ping Li
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou Key Laboratory Environmental Catalysis and Pollution Control, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Guangzhou 510006, PR China
| | - Shaosong Huang
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou Key Laboratory Environmental Catalysis and Pollution Control, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Guangzhou 510006, PR China
| | - Fenglian Fu
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou Key Laboratory Environmental Catalysis and Pollution Control, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Guangzhou 510006, PR China
| | - Bing Tang
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou Key Laboratory Environmental Catalysis and Pollution Control, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Guangzhou 510006, PR China.
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Chen X, Wang J, Wang Q, Yuan T, Lei Z, Zhang Z, Shimizu K, Lee DJ. Simultaneous recovery of phosphorus and alginate-like exopolysaccharides from two types of aerobic granular sludge. BIORESOURCE TECHNOLOGY 2022; 346:126411. [PMID: 34838630 DOI: 10.1016/j.biortech.2021.126411] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Revised: 11/17/2021] [Accepted: 11/19/2021] [Indexed: 06/13/2023]
Abstract
Wastewater treatment plants are expected to realize not only pollutants removal from wastewater but also resources recovery such as phosphorus (P) and alginate-like exopolysaccharides (ALE) from the produced sludge. In this study, ALE extraction and fractionation from the same activated sludge-derived bacterial aerobic granular sludge (AGS) and algal-bacterial AGS were performed in addition to P fate examination during ALE recovery. Results showed that the ALE content recovered from algal-bacterial AGS was 8.81 ± 0.02 mg/g-volatile suspended solids (VSS), about 2.8 times higher than that from bacterial AGS when fed with the same synthetic wastewater. Moreover, the mannuronic acid to guluronic acid (MG) blocks accounted for the largest proportion of ALE from the two granular sludges. In particular, the extracellular polymeric substances (EPS) extracted from bacterial and algal-bacterial AGS contained about 25.10 ± 1.85 and 19.53 ± 0.04 mg-P/g-SS, respectively, and both granular sludges possessed high P bioavailability of 97-99%.
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Affiliation(s)
- Xingyu Chen
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Jixiang Wang
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Qian Wang
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Tian Yuan
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Zhongfang Lei
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan.
| | - Zhenya Zhang
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Kazuya Shimizu
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Duu-Jong Lee
- Department of Chemical Engineering, National Taiwan University, Taipei 106, Taiwan; Department of Mechanical Engineering, City University of Hong Kong, Kowloon Tang, Hong Kong
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Zheng J, Wang N, Zhao L, Li Y, Yu J, Wang S. Microbial population changes and metabolic shift of candidatus accumulibacter under low temperature and limiting polyphosphate. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2022; 85:1107-1119. [PMID: 35228357 DOI: 10.2166/wst.2022.036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
This study explored the microbial population dynamics of Accumulibacter (Acc) at low temperature and metabolic shift to limiting polyphosphate (Poly-P) in enhanced biological phosphorus removal (EBPR) system. The Accumulibacter-enriched EBPR systems, fed with acetate (HAc) and propionate (HPr) at 10 ± 1 °C respectively, were operated for 60 days in two identical SBR reactors (SBR-1 and SBR-2). The phosphorus removal performance in two systems was stable at 10 ± 1 °C, while the microbial community structure changed. Compared with the population structure in seed sludge, Accumulibacter clades reduced in the HAc system, while Acc I increased significantly in the HPr system. Low temperature was beneficial to the formation of granular sludge in the EBPR system, and the sludge granulation in the HAc system was more homogeneous than that in the HPr system. Accumulibacter in the HPr system can get ATP through glycogen accumulating metabolism (GAM) under limiting Poly-P condition at 10 ± 1 °C, while that in the HAc system cannot. This work suggests that poly-P levels can affect the metabolic pathway of Accumulibacter in EBPR systems under low temperature.
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Affiliation(s)
- Jianfeng Zheng
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Jinjing Road 26, Tianjin 300384, China E-mail: ; Tianjin Key Laboratory of Aquatic Science and Technology, Jinjing Road 26, Tianjin, China; Joint Research Centre for Protective Infrastructure Technology and Environmental Green Bioprocess, School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, China
| | - Nan Wang
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Jinjing Road 26, Tianjin 300384, China E-mail: ; Tianjin Key Laboratory of Aquatic Science and Technology, Jinjing Road 26, Tianjin, China; Joint Research Centre for Protective Infrastructure Technology and Environmental Green Bioprocess, School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, China
| | - Ledan Zhao
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Jinjing Road 26, Tianjin 300384, China E-mail: ; Tianjin Key Laboratory of Aquatic Science and Technology, Jinjing Road 26, Tianjin, China; Joint Research Centre for Protective Infrastructure Technology and Environmental Green Bioprocess, School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, China
| | - Yajing Li
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Jinjing Road 26, Tianjin 300384, China E-mail: ; Tianjin Key Laboratory of Aquatic Science and Technology, Jinjing Road 26, Tianjin, China; Joint Research Centre for Protective Infrastructure Technology and Environmental Green Bioprocess, School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, China
| | - Jingjie Yu
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Jinjing Road 26, Tianjin 300384, China E-mail: ; Tianjin Key Laboratory of Aquatic Science and Technology, Jinjing Road 26, Tianjin, China; Joint Research Centre for Protective Infrastructure Technology and Environmental Green Bioprocess, School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, China
| | - Shaopo Wang
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Jinjing Road 26, Tianjin 300384, China E-mail: ; Tianjin Key Laboratory of Aquatic Science and Technology, Jinjing Road 26, Tianjin, China; Joint Research Centre for Protective Infrastructure Technology and Environmental Green Bioprocess, School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, China
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Sarvajith M, Nancharaiah YV. Enhancing biological nitrogen and phosphorus removal performance in aerobic granular sludge sequencing batch reactors by activated carbon particles. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 303:114134. [PMID: 34839174 DOI: 10.1016/j.jenvman.2021.114134] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 11/18/2021] [Accepted: 11/18/2021] [Indexed: 06/13/2023]
Abstract
Long start-up periods for aerobic granular sludge (AGS) formation and establishment of P removal pathways are challenges for widespread implementation of AGS process. External additives such as activated carbon (AC) attracted interest for accelerating AGS formation. However, the roles of AC in granulation and biological nutrient removal (BNR) are not understood. Here, the role of AC was investigated in decreasing start-up periods in AGS formation and BNR under different carbon substrate conditions (i.e., acetate (HAc), propionate (HPr) and HAc-HPr) in sequencing batch reactors (SBRs). AC addition increased aggregation index and settleability of activated sludge (AS) inoculum which minimized AS washout from SBRs. AC addition hastened AGS formation and establishment of BNR pathways by facilitating AS retention and biofilm formation. Feeding HAc or HAc-HPr supported better granulation (MLSS: 6-7 g l-1, SVI: 30-40 ml g-1) than HPr (MLSS: 4 g l-1, SVI: 70). The start-up periods for efficient total nitrogen (TN) removals were decreased to 22 and 16 d from 38 to 25 d, respectively, in AC augmented SBRs fed with either HAc or HAc-HPr. TN removals were higher at ≥95% in HAc or HAc-HPr fed SBRs. Total phosphorus (TP) removals were also higher in AC-augmented SBRs at 80% and ≥90% in HAc and HAc-HPr fed SBRs, respectively. In contrast, TN and TP removals were lower at 70% and 35%, respectively, in HPr fed SBR. Ammonium was primarily removed via nitritation-denitritation pathway. Phosphorus removal was at 1.7 to 2-fold higher in AC augmented SBRs and driven by enhanced biological phosphorus removal (EBPR) pathway. MiSeq sequencing and qPCR revealed higher enrichment of polyphosphate accumulating organisms (PAOs), denitrifying PAOs, and ammonia oxidizers in AC-augmented SBRs fed with HAc or HAc-HPr. This study demonstrates that AC addition can be considered for enrichment of PAOs and establishment of EBPR in aerobic granular SBRs.
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Affiliation(s)
- M Sarvajith
- Biofouling and Biofilm Processes Section, WSCD, Chemistry Group, Bhabha Atomic Research Centre, Kalpakkam, 603102, Tamil Nadu, India; Homi Bhabha National Institute, BARC Training School Complex, Anushakti Nagar, Trombay, Mumbai, 400 094, India
| | - Y V Nancharaiah
- Biofouling and Biofilm Processes Section, WSCD, Chemistry Group, Bhabha Atomic Research Centre, Kalpakkam, 603102, Tamil Nadu, India; Homi Bhabha National Institute, BARC Training School Complex, Anushakti Nagar, Trombay, Mumbai, 400 094, India.
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37
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Hu ZY, Wang S, Geng ZQ, Dai K, Ji WX, Tian YC, Li WT, Zeng RJ, Zhang F. Controlling volatile fatty acids production from waste activated sludge by an alginate-degrading consortium. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 806:150730. [PMID: 34606857 DOI: 10.1016/j.scitotenv.2021.150730] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Revised: 09/26/2021] [Accepted: 09/28/2021] [Indexed: 06/13/2023]
Abstract
It is desirable to control volatile fatty acids (VFAs) recovery from waste activated sludge (WAS) while avoiding the release of N and P. Structural extracellular polymeric substances (St-EPS), with typical components of alginate and polygalacturonic acid, resist the biodegradation of extracellular polymeric substances (EPS) in WAS. Previously, we purposely enriched an alginate-degrading consortium (ADC), but, both controlling VFAs production and cell integrity after dosing with ADC were not investigated. In this work, ADC with a high percentage of the genus Bacteroides (~67%) was further enriched with alginate utilization above 95%. The St-EPS content in WAS was 109.7 ± 3.3 mg/g-VSS, accounting for 31% of EPS. After dosing ADC in the WAS, the main metabolites were acetate (1.6 g/L) and propionate (0.7 g/L), the hydrolysis efficiency was increased to 38%, and the acidification efficiency was increased to 72%. Cell integrity was maintained during WAS fermentation by dosing with ADC according to no P release and unchanged lactate dehydrogenase activity. VFA production was mainly from the EPS, and protein degradation in EPS resulted in low N release (e.g., 212 mg/L from casein and no P release). Consequently, ADC doing offers the advantages of controlling VFAs production from EPS while maintaining cell integrity.
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Affiliation(s)
- Zhi-Yi Hu
- Center of Wastewater Resource Recovery, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Shuai Wang
- Center of Wastewater Resource Recovery, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Zi-Qian Geng
- Center of Wastewater Resource Recovery, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Kun Dai
- Center of Wastewater Resource Recovery, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Wen-Xiang Ji
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Ye-Chao Tian
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Wen-Tao Li
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Raymond Jianxiong Zeng
- Center of Wastewater Resource Recovery, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Fang Zhang
- Center of Wastewater Resource Recovery, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China.
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38
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Kim NK, Lin R, Bhattacharyya D, van Loosdrecht MCM, Lin Y. Insight on how biopolymers recovered from aerobic granular wastewater sludge can reduce the flammability of synthetic polymers. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 805:150434. [PMID: 34818807 DOI: 10.1016/j.scitotenv.2021.150434] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Revised: 09/14/2021] [Accepted: 09/14/2021] [Indexed: 06/13/2023]
Abstract
Eco-friendly flame retardants are greatly required to meet the expectations of low-toxicity, environmental compatibility and sustainability. Extracellular polymeric substances (EPS), the biopolymers recovered from excess granular wastewater sludge, have been successfully incorporated into poly(vinyl alcohol) (PVA) by a solution casting method. Self-extinguishment of EPS was observed in a vertical burn test. Positive effects of EPS on the reduction of heat release rate and CO emission of EPS/PVA composites were also demonstrated. The presence of various types of phosphates was detected in the EPS and a possible flame-retardant mechanism has been proposed. The investigation of using granular sludge EPS to reduce the flammability of synthetic polymers may open the possibility of converting wastewater sludge into bio phosphorus-based flame retardants.
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Affiliation(s)
- Nam Kyeun Kim
- Centre for Advanced Composite Materials, Department of Mechanical Engineering, University of Auckland, New Zealand.
| | - Richard Lin
- Centre for Advanced Composite Materials, Department of Mechanical Engineering, University of Auckland, New Zealand
| | - Debes Bhattacharyya
- Centre for Advanced Composite Materials, Department of Mechanical Engineering, University of Auckland, New Zealand
| | | | - Yuemei Lin
- Department of Biotechnology, Delft University of Technology, Delft, the Netherlands
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39
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Geng ZQ, Qian DK, Hu ZY, Wang S, Yan Y, van Loosdrecht MCM, Zeng RJ, Zhang F. Identification of Extracellular Key Enzyme and Intracellular Metabolic Pathway in Alginate-Degrading Consortia via an Integrated Metaproteomic/Metagenomic Analysis. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:16636-16645. [PMID: 34860015 DOI: 10.1021/acs.est.1c05289] [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] [Indexed: 06/13/2023]
Abstract
Uronic acid in extracellular polymeric substances is a primary but often ignored factor related to the difficult hydrolysis of waste-activated sludge (WAS), with alginate as a typical polymer. Previously, we enriched alginate-degrading consortia (ADC) in batch reactors that can enhance methane production from WAS, but the enzymes and metabolic pathway are not well documented. In this work, two chemostats in series were operated to enrich ADC, in which 10 g/L alginate was wholly consumed. Based on it, the extracellular alginate lyase (∼130 kD, EC 4.2.2.3) in the cultures was identified by metaproteomic analysis. This enzyme offers a high specificity to convert alginate to disaccharides over other mentioned hydrolases. Genus Bacteroides (>60%) was revealed as the key bacterium for alginate conversion. A new Entner-Doudoroff pathway of alginate via 5-dehydro-4-deoxy-d-glucuronate (DDG) and 3-deoxy-d-glycerol-2,5-hexdiulosonate (DGH) as the intermediates to 2-keto-3-deoxy-gluconate (KDG) was constructed based on the metagenomic and metaproteomic analysis. In summary, this work documented the core enzymes and metabolic pathway for alginate degradation, which provides a good paradigm when analyzing the degrading mechanism of unacquainted substrates. The outcome will further contribute to the application of Bacteroides-dominated ADC on WAS methanogenesis in the future.
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Affiliation(s)
- Zi-Qian Geng
- Center of Wastewater Resource Recovery, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Ding-Kang Qian
- Center of Wastewater Resource Recovery, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Zhi-Yi Hu
- Center of Wastewater Resource Recovery, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Shuai Wang
- Center of Wastewater Resource Recovery, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Yang Yan
- Center of Wastewater Resource Recovery, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Mark C M van Loosdrecht
- Department of Biotechnology, Delft University of Technology, Julianalaan 67, Delft 2628 BC, The Netherlands
| | - Raymond Jianxiong Zeng
- Center of Wastewater Resource Recovery, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Fang Zhang
- Center of Wastewater Resource Recovery, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
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40
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Pfaff NM, Dijksman JA, Kemperman AJB, van Loosdrecht MCM, Kleijn JM. Rheological characterisation of alginate-like exopolymer gels crosslinked with calcium. WATER RESEARCH 2021; 207:117835. [PMID: 34775170 DOI: 10.1016/j.watres.2021.117835] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 10/31/2021] [Accepted: 11/01/2021] [Indexed: 06/13/2023]
Abstract
Bacterial alginate-like exopolymers (ALE) gels have been used in this work as a model for the extracellular polymeric matrix of biofilms. Aim was to relate the mechanical properties and strength of this matrix that make biofilms as persistent to cleaning as they are, to the complex cohesive molecular interactions involved. Mechanical properties of the gels as a function of CaCO3 concentration were investigated using dynamic and static rheology. Gels with relatively low CaCO3 concentrations, between 100 μmol and 300 μmol per g ALE, were found to exhibit similar viscoelastic behaviour as real biofilms, with elastic moduli between 50 Pa and 100 Pa and dissipation factors between 0.2 and 0.3. Increasing CaCO3 concentrations resulted in an increase of the elastic modulus up to 250 Pa, accompanied by an increase in brittleness. At a CaCO3 concentration of 1250 μmol per g ALE this trend stopped, probably due to disturbance of the continuous ALE network by precipitation of salts. Therefore, overdosing of Ca salts can be an adequate approach for the removal of biofouling. All gels exhibited permanent strain hardening under medium strain, and their mechanical properties showed dependency on their strain history. Even after application of an oscillatory strain with 200% amplitude that caused the gel structure to collapse, the gels recovered 65 to 90% of their original shear modulus, for the major part within the first 20 s. Recovery was slightly less for gels with high CaCO3 concentration. In creep tests fitted with a Burgers model with multiple Kelvin elements at least three different interactions in the ALE gels could be distinguished with characteristic retardation times in the range of 10, 100 and 1000 s. Further identification of the mechanisms underlying the gel mechanics will allow the development of targeted strategies to undermine the mechanical strength of biofouling and aid the cleaning process.
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Affiliation(s)
- N M Pfaff
- Department of Biotechnology, TU Delft, Van der Maasweg 9, HZ, Delft 2629, the Netherland; Wetsus, European Center of Excellence for Sustainable Water Technology, Oostergoweg 9, MA, Leeuwarden 8911, the Netherland
| | - J A Dijksman
- Physical Chemistry and Soft Matter, Wageningen University, Stippeneng 4, WE, Wageningen 6708, the Netherland
| | - A J B Kemperman
- Membrane Science and Technology cluster, Faculty of Science and Technology, Mesa+ Institute for Nanotechnology, University of Twente, P.O. Box 217, AE, Enschede 7500, the Netherland; Wetsus, European Center of Excellence for Sustainable Water Technology, Oostergoweg 9, MA, Leeuwarden 8911, the Netherland
| | - M C M van Loosdrecht
- Department of Biotechnology, TU Delft, Van der Maasweg 9, HZ, Delft 2629, the Netherland.
| | - J M Kleijn
- Physical Chemistry and Soft Matter, Wageningen University, Stippeneng 4, WE, Wageningen 6708, the Netherland
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41
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Li Z, Li H, Zhao L, Liu X, Wan C. Understanding the role of cations and hydrogen bonds on the stability of aerobic granules from the perspective of the aggregation and adhesion behavior of extracellular polymeric substances. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 795:148659. [PMID: 34237538 DOI: 10.1016/j.scitotenv.2021.148659] [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: 05/11/2021] [Revised: 06/19/2021] [Accepted: 06/21/2021] [Indexed: 06/13/2023]
Abstract
Extracellular polymeric substances (EPS) were essential for the granulation and stability of aerobic granular sludge (AGS). In this study, the effects of electrostatic interactions, bridging effect of divalent cations, and hydrogen bonds on the EPS-EPS and EPS-surface interaction were verified by enhancing or reducing the specific interaction with the addition of cations or urea. The size and the surface properties of EPS aggregates were investigated, the adhesion behavior and viscoelasticity of EPS were analyzed by quartz crystal microbalance with dissipation monitoring. The changes of EPS in response to the various condition were analyzed by infrared spectroscopy and fluorescence spectrum. The electrostatic repulsion between EPS could be significantly reduced by Ca2+ addition. With the bridging effect, 10 μM of Ca2+ could reduce the negative charge of EPS more effectively than 200 μM of Na+. As Ca2+ could form the complex with the protein and Ca2+ was more inclined to bind with COO-, the Ca2+ took advantage of boosting the EPS-EPS and EPS-surface interaction than Mg2+ at the same ionic strength, which resulted in the denser structure of calcium-treated EPS. The destruction of hydrogen bonds by urea addition reduced the EPS-EPS and EPS-surface interaction, which confirmed the potential existence of hydrogen bonds in the interaction of EPS-EPS and EPS-surface. The removal of hydrogen bonds of EPS destroyed the protein's secondary structure and caused the unfolded state of the protein, which led to the looser structure of the EPS layer.
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Affiliation(s)
- Zhengwen Li
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China
| | - Huiqi Li
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China
| | - Lianfa Zhao
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China
| | - Xiang Liu
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China
| | - Chunli Wan
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China.
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42
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Li J, Hao X, Gan W, van Loosdrecht MCM, Wu Y. Recovery of extracellular biopolymers from conventional activated sludge: Potential, characteristics and limitation. WATER RESEARCH 2021; 205:117706. [PMID: 34600231 DOI: 10.1016/j.watres.2021.117706] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 09/16/2021] [Accepted: 09/21/2021] [Indexed: 06/13/2023]
Abstract
Extracellular polymeric substances (EPS) are biopolymers that can be recovered from excess sludge, which could contribute to a more sustainable wastewater treatment plant (WWTP) operation. An example is alginate like extracellular polymers (ALE) contained in the biopolymers could be a potential resource with a highly-added value. EPS extraction for ALE from aerobic granules sludge (AGS) has already been well studied and applied in the Netherlands. On the other hand, there is little attention to the recovery of biopolymers from conventional activated sludge (CAS). In this study, flocculent sludge from eight CAS-WWTPs in China was collected and their EPS/biopolymers were extracted to investigate their recovery potential, chemical & physical properties and limiting factors. The results revealed that the biopolymers extracted and purified from CAS ranged from 90 to 190 mg/g VSS. The compositional characteristics of the biopolymers were observed by FT-IR, 3D-EEM and UV-Visible spectra, demonstrating some differences in the composition and property of the biopolymers from the different WWTPs. The biopolymers had a similarity of about 60% to a commercial alginate with respect to chemical functional groups and the alginate equivalent was >400 mg/g biopolymers. Moreover, the biopolymers consisted of poly (guluronic acid) blocks (20%-30%) and poly (guluronic acid-mannuronic acid) blocks (8%-28%), and the ionic hydrogel formation tests indicated that condensed beads were immediately formed once the drops of the biopolymers came in contact with CaCl2 solution. These results demonstrated that the biopolymers extracted had a relatively high gel-forming capacity and might also have a potential application as commercial biopolymers. Furthermore, the factors influencing the biopolymers' formation such as influent substrate, nutrient content and microbial community and the related mechanisms were investigated. Among them, increasing soluble organics (SCOD) content and low nutrient content (C/N/P) in the influent could promote the biopolymers' formation. Also, different bacteria in BNR processes might have positive or negative effects on the biopolymers' formation. In conclusion, the diversity and abundance of bacteria were identified to be a crucial and decisive factor controlling biopolymers' extraction and composition.
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Affiliation(s)
- Ji Li
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies/Beijing Advanced Innovation Centre of Future Urban Design, Beijing University of Civil Engineering & Architecture, Beijing 100044, PR China
| | - Xiaodi Hao
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies/Beijing Advanced Innovation Centre of Future Urban Design, Beijing University of Civil Engineering & Architecture, Beijing 100044, PR China
| | - Wei Gan
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies/Beijing Advanced Innovation Centre of Future Urban Design, Beijing University of Civil Engineering & Architecture, Beijing 100044, PR China
| | - Mark C M van Loosdrecht
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies/Beijing Advanced Innovation Centre of Future Urban Design, Beijing University of Civil Engineering & Architecture, Beijing 100044, PR China; Dept. of Biotechnology, Delft University of Technology, van der Maasweg 9, 2629 HZ Delft, the Netherlands
| | - Yuanyuan Wu
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies/Beijing Advanced Innovation Centre of Future Urban Design, Beijing University of Civil Engineering & Architecture, Beijing 100044, PR China
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43
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Duque AF, Campo R, Val del Rio A, Amorim CL. Wastewater Valorization: Practice around the World at Pilot- and Full-Scale. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18189466. [PMID: 34574414 PMCID: PMC8472693 DOI: 10.3390/ijerph18189466] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 09/01/2021] [Accepted: 09/03/2021] [Indexed: 11/16/2022]
Abstract
Over the last few years, wastewater treatment plants (WWTPs) have been rebranded as water resource recovery facilities (WRRFs), which recognize the resource recovery potential that exists in wastewater streams. WRRFs contribute to a circular economy by not only producing clean water but by recovering valuable resources such as nutrients, energy, and other bio-based materials. To this aim, huge efforts in technological progress have been made to valorize sewage and sewage sludge, transforming them into valuable resources. This review summarizes some of the widely used and effective strategies applied at pilot- and full-scale settings in order to valorize the wastewater treatment process. An overview of the different technologies applied in the water and sludge line is presented, covering a broad range of resources, i.e., water, biomass, energy, nutrients, volatile fatty acids (VFA), polyhydroxyalkanoates (PHA), and exopolymeric substances (EPS). Moreover, guidelines and regulations around the world related to water reuse and resource valorization are reviewed.
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Affiliation(s)
- Anouk F. Duque
- Associate Laboratory i4HB—Institute for Health and Bioeconomy, NOVA School of Science and Technology, NOVA University Lisbon, 1099-085 Lisboa, Portugal;
- UCIBIO—Applied Molecular Biosciences Unit, Department of Chemistry, NOVA School of Science and Technology, NOVA University Lisbon, 1099-085 Lisboa, Portugal
| | - Riccardo Campo
- DICEA—Dipartimento di Ingegneria Civile e Ambientale, Università degli Studi di Firenze, Via di S. Marta 3, 50139 Florence, Italy;
| | - Angeles Val del Rio
- Department of Chemical Engineering, CRETUS Institute, Universidade de Santiago de Compostela, Rúa Lope Gómez de Marzoa s/n, E-15705 Santiago de Compostela, Spain;
| | - Catarina L. Amorim
- CBQF—Centro de Biotecnologia e Química Fina—Laboratório Associado, Escola Superior de Biotecnologia, Universidade Católica Portuguesa, Rua Diogo Botelho 1327, 4169-005 Porto, Portugal
- Correspondence: ; Tel.: +351-226-196-200
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Tavares Ferreira TJ, Luiz de Sousa Rollemberg S, Nascimento de Barros A, Machado de Lima JP, Bezerra Dos Santos A. Integrated review of resource recovery on aerobic granular sludge systems: Possibilities and challenges for the application of the biorefinery concept. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 291:112718. [PMID: 33962280 DOI: 10.1016/j.jenvman.2021.112718] [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: 11/25/2020] [Revised: 04/15/2021] [Accepted: 04/25/2021] [Indexed: 06/12/2023]
Abstract
Aerobic Granular Sludge (AGS) is a biological treatment technology that has been extensively studied in the last decade. The possibility of resource recovery has always been highlighted in these systems, but real-scale applications are still scarce. Therefore, this paper aimed to present a systematic review of resources recovery such as water, energy, chemicals, raw materials, and nutrients from AGS systems, also analyzing aspects of engineering and economic viability. In the solid phase, sludge application in agriculture is an interesting possibility. However, the biosolids' metal concentration (the granules have high adsorption capacity due to the high concentration of extracellular polymeric substances, EPS) may be an issue. Another possibility is the recovery of Polyhydroxyalkanoates (PHAs) and Alginate-like exopolymers (bio-ALE) in the solid phase, emphasizing the last one, which has already been made in some Wastewater Treatment Plants (WWTPs), named and patented as Kaumera® process. The Operational Expenditure (OPEX) can be reduced by 50% in the WWTP when recovery of ALE is made. The ALE recovery reduced sludge yield by up to 35%, less CO2 emissions, and energy saving. Finally, the discharged sludge can also be evaluated to be used for energetic purposes via anaerobic digestion (AD) or combustion. However, the AD route has faced difficulties due to the low biodegradability of aerobic granules.
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Affiliation(s)
| | | | - Amanda Nascimento de Barros
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - João Pedro Machado de Lima
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - André Bezerra Dos Santos
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil.
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Oliveira AS, Amorim CL, Zlopasa J, van Loosdrecht M, Castro PML. Recovered granular sludge extracellular polymeric substances as carrier for bioaugmentation of granular sludge reactor. CHEMOSPHERE 2021; 275:130037. [PMID: 33667767 DOI: 10.1016/j.chemosphere.2021.130037] [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: 09/23/2020] [Revised: 02/11/2021] [Accepted: 02/14/2021] [Indexed: 06/12/2023]
Abstract
An increasing amount of industrial chemicals are being released into wastewater collection systems and indigenous microbial communities in treatment plants are not always effective for their removal. In this work, extracellular polymeric substances (EPS) recovered from aerobic granular sludge (AGS) were used as a natural carrier to immobilize a specific microbial strain, Rhodococcus sp. FP1, able to degrade 2-fluorophenol (2-FP). The produced EPS granules exhibited a 2-FP degrading ability of 100% in batch assays, retaining their original activity after up to 2-months storage. Furthermore, EPS granules were added to an AGS reactor intermittently fed with saline wastewater containing 2-FP. Degradation of 2-FP and stoichiometric fluorine release occurred 8 and 35 days after bioaugmentation, respectively. Chemical oxygen demand removal was not significantly impaired by 2-FP or salinity loads. Nutrients removal was impaired by 2-FP load, but after bioaugmentation, the phosphate and ammonium removal efficiency improved from 14 to 46% and from 25 to 42%, respectively. After 2-FP feeding ceased, at low/moderate salinity (0.6-6.0 g L-1 NaCl), ammonium removal was completely restored, and phosphate removal efficiency increased. After bioaugmentation, 11 bacteria isolated from AGS were able to degrade 2-FP, indicating that horizontal gene transfer could have occurred in the reactor. The improvement of bioreactor performance after bioaugmentation with EPS immobilized bacteria and the maintenance of cell viability through storage are the main advantages of the use of this natural microbial carrier for bioaugmentation, which can benefit wastewater treatment processes.
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Affiliation(s)
- Ana S Oliveira
- Universidade Católica Portuguesa, CBQF - Centro de Biotecnologia e Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, Rua Diogo Botelho 1327, 4169-005, Porto, Portugal
| | - Catarina L Amorim
- Universidade Católica Portuguesa, CBQF - Centro de Biotecnologia e Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, Rua Diogo Botelho 1327, 4169-005, Porto, Portugal.
| | - Jure Zlopasa
- Department of Biotechnology, Delft University of Technology, van der Maasweg 9, 2629 HZ, Delft, the Netherlands
| | - Mark van Loosdrecht
- Department of Biotechnology, Delft University of Technology, van der Maasweg 9, 2629 HZ, Delft, the Netherlands
| | - Paula M L Castro
- Universidade Católica Portuguesa, CBQF - Centro de Biotecnologia e Química Fina - Laboratório Associado, Escola Superior de Biotecnologia, Rua Diogo Botelho 1327, 4169-005, Porto, Portugal
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46
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Li C, Sheng Y. Organic matter affects phosphorus recovery during vivianite crystallization. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2021; 83:2038-2050. [PMID: 33905371 DOI: 10.2166/wst.2021.112] [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
Vivianite crystallization is a promising route for phosphorus (P) recovery from P-rich wastewater. However, organic matter (OM) in wastewater may influence vivianite formation. In this study, the effects of four representative OMs, glucose, bovine serum albumin (BSA), humic acid (HA) and sodium alginate (SA), on P recovery by vivianite were investigated. The results showed that P recovery efficiency was inhibited by HA and SA, declining by 3.7% and 12.1% under HA (100 mg/L) and SA (800 mg/L), respectively. BSA, HA and SA affected the aggregated form of vivianite crystals. Vivianite particle size decreased in the presence of HA and SA. Subsequent mechanistic exploration indicated that the complexation between the OM and Fe2+ was the main cause of P recovery efficiency reduction. The coprecipitation of HA and SA with vivianite could reduce the zeta potential on the crystal surface, resulting in a smaller particle size. The nucleation sites provided by BSA and SA could transfer vivianite from single plate-like agglomerate to multilayer plate-like agglomerate. This study provided a better understanding of P recovery by vivianite from OM-rich wastewater.
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Affiliation(s)
- Changyu Li
- Research Center for Coastal Environment Engineering Technology of Shandong Province, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, China E-mail: ; University of Chinese Academy of Sciences, Beijing, China
| | - Yanqing Sheng
- Research Center for Coastal Environment Engineering Technology of Shandong Province, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, China E-mail:
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Zheng Z, Li J, Wang C. Rapid cultivation of the aerobic granules for simultaneous phenol degradation and ammonium oxidation in a sequencing batch reactor. BIORESOURCE TECHNOLOGY 2021; 325:124414. [PMID: 33493744 DOI: 10.1016/j.biortech.2020.124414] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 11/08/2020] [Accepted: 11/11/2020] [Indexed: 06/12/2023]
Abstract
The rapid cultivation strategy of aerobic granular sludge (AGS) for simultaneous phenol degradation and ammonium oxidation was studied in a sequence batch reactor (SBR). The short-term inhibitory kinetics of phenol was studied through batch experiments. For the sodium acetate fed AGS, the phenol inhibition constants (Ki) of specific oxygen utilization rate by heterotrophic bacteria (SOURh) was 508.6 mg/L. The Ki of specific ammonium utilization rate (SAUR) was 232.3 mg/L. After 28 days' acclimatization, the phenol and NH4+-N removal rates of the SBR reached 94.0% and 96.4% when the influent phenol and NH4+-N concentrations were 1000 and 33.5 mg/L, respectively. The phenol removal loading rate was 1.69 kg/(m3·d). For the mature phenol&ammonium degrading AGS, the polysaccharide (PS) and protein (PN) concentrations were 247.4 ± 10.3 and 68.6 ± 6.5 mg/g VSS, respectively. The functional groups analysis showed that the amount of OH, NH, CO and CC groups remained unchanged in the mature phenol&ammonium degrading AGS.
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Affiliation(s)
- Zhaoming Zheng
- National Engineering Laboratory for Wastewater Treatment Technology, Beijing University of Technology, Beijing 100124, China
| | - Jun Li
- National Engineering Laboratory for Wastewater Treatment Technology, Beijing University of Technology, Beijing 100124, China.
| | - Changwen Wang
- National Engineering Laboratory for Wastewater Treatment Technology, Beijing University of Technology, Beijing 100124, China
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Wang S, Liu Z, Yang M, Zhou Y, Yang M, Long M, Fang F, Guo J. The differences in characteristics of extracellular polymeric substances of flocs and anammox granules impacted aggregation. Bioprocess Biosyst Eng 2021; 44:1711-1720. [PMID: 33768321 DOI: 10.1007/s00449-021-02554-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Accepted: 03/16/2021] [Indexed: 10/21/2022]
Abstract
Extracellular polymeric substances (EPS) are considered crucial components in the formation of microbial aggregates such as biofilms, flocs and granules. However, the role of EPS in sludge aggregation is still unclear. In this study, the differences in EPS characteristics of anammox granular sludge (AG), anammox floc sludge (AF) and activated floc sludge (AS) were investigated to clarify its role in granular aggregation. The results showed that the flocculation ability of EPS extracted from AG (62.8 ± 2.3%) was notably higher than that of EPS extracted from AF (35.7 ± 1.7%) and AS (17.3 ± 1.5%). The zeta potential and hydrophobicity of EPS showed the same tendency. In addition, the PN/PS ratio of AG, AF and AS were 7.66, 4.62 and 3.93, respectively. FTIR, XPS and 3D-EEM fluorescence spectra results revealed that anammox granular sludge has a higher ratio of hydrophobic groups, α-helixs/(β-sheets and random coils), intermolecular hydrogen bonds, and aromatic amino acids, and a lower ratio of electronegative groups. Anammox granular sludge exhibited high aggregation ability, because its EPS had higher zeta potential, hydrophobicity and intermolecular hydrogen bond ratio. This work provides a better understanding of the high aggregation ability of anammox granules and a theoretical basis for improving granules proportion and retention ability of microbes in reactor system.
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Affiliation(s)
- Shuai Wang
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Zihan Liu
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Mingming Yang
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China.,Yangtze Ecology and Environment Co., Ltd, Wuhan, 430062, China
| | - Yang Zhou
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Mansu Yang
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Man Long
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Fang Fang
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China.
| | - Jinsong Guo
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
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49
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Feng C, Lotti T, Canziani R, Lin Y, Tagliabue C, Malpei F. Extracellular biopolymers recovered as raw biomaterials from waste granular sludge and potential applications: A critical review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 753:142051. [PMID: 33207449 DOI: 10.1016/j.scitotenv.2020.142051] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 08/26/2020] [Accepted: 08/27/2020] [Indexed: 06/11/2023]
Abstract
Granular sludge (GS) is a special self-aggregation biofilm. Extracellular polymeric substances (EPS) are mainly associated with the architectural structure, rheological behaviour and functional stability of fine granules, given that their significance to the physicochemical features of the biomass catalysing the biological purification process. This review targets the EPS excretion from GS and introduces newly identified EPS components, EPS distribution in different granules, how to effectively extract and recover EPS from granules, key parameters affecting EPS production, and the potential applications of EPS-based biomaterials. GS-based EPS components are highly diverse and a series of new contents are highlighted. Due to high diversity, emerging extraction standards are proposed and recovery process is capturing particular attention. The major components of EPS are found to be polysaccharides and proteins, which manifest a larger diversity of relative abundance, structures, physical and chemical characteristics, leading to the possibility to sustainably recover raw materials. EPS-based biomaterials not only act as alternatives to synthetic polymers in several applications but also figure in innovative industrial/environmental applications, including gel-forming materials for paper industry, biosorbents, cement curing materials, and flame retardant materials. In the upcoming years, it is foreseen that productions of EPS-based biomaterials from renewable origins would make a significant contribution to the advancement of the circular economy.
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Affiliation(s)
- Cuijie Feng
- Department of Civil and Environmental Engineering, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan, Italy.
| | - Tommaso Lotti
- Department of Civil and Environmental Engineering, University of Florence, Via di Santa Marta 3, 50139 Florence, Italy
| | - Roberto Canziani
- Department of Civil and Environmental Engineering, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan, Italy
| | - Yuemei Lin
- Department of Biotechnology, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, the Netherlands
| | - Camilla Tagliabue
- Department of Civil and Environmental Engineering, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan, Italy
| | - Francesca Malpei
- Department of Civil and Environmental Engineering, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan, Italy
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50
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Wang BB, Luo Q, Li HJ, Yao Q, Zhang L, Zou JT, He F. Characterization of aerobic granules formed in an aspartic acid fed sequencing batch reactor under unfavorable hydrodynamic selection conditions. CHEMOSPHERE 2020; 260:127600. [PMID: 32758769 DOI: 10.1016/j.chemosphere.2020.127600] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 05/27/2020] [Accepted: 06/30/2020] [Indexed: 06/11/2023]
Abstract
Granules initiation and development is the backbone of aerobic granular sludge technology. Feed composition can notably affect initiation and development of aerobic granules, and yield aerobic granules with distinct microbial community, morphology and structure. This paper reports an unexpected formation of aerobic granules in an aspartic acid fed SBR under unfavorable hydrodynamic selection conditions. Detailed characteristics of these aerobic granules were investigated in terms of morphology, structure, bioactivity and EPS. The results showed that due to the absence of favorable hydrodynamic selection pressure, the formed aerobic granules had an irregular shape with a rough outline and loose internal structure, which was quite different from mature aerobic granules. Bacteria in these aerobic granules were mainly presented in the form of microcolony with calcium and β-polysaccharides responsible for its mechanical stability. The high N/C ratio of aspartic acid enabled the enrichment of significant amount of nitrifiers within aerobic granules and thus resulted in high nitrification activity of these aerobic granules. The negatively charged and hydrophilic aspartic acid also induced the bacteria to secrete more exopolysaccharides for contributing to more neutral and hydrophilic surface of the aerobic granules, which was beneficial for aspartic acid capture. As a result, polysaccharides, rather than proteins, became the major components of EPS in these aerobic granules. This paper provides us a foundation to better understand the granulation potential of proteinaceous substrates that is frequently encountered in industrial wastewaters.
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Affiliation(s)
- Bin-Bin Wang
- College of Environment, Zhejiang University of Technology, Hangzhou, Zhejiang, 310014, China
| | - Qin Luo
- College of Environment, Zhejiang University of Technology, Hangzhou, Zhejiang, 310014, China
| | - Hui-Juan Li
- School of Environmental and Chemical Engineering, Xi'an Polytechnic University, Xi'an, Shaanxi, 710048, China
| | - Qian Yao
- School of Biological and Environmental Engineering, Xi'an University, Xi'an, Shaanxi, 710065, China
| | - Lin Zhang
- Center for Environmental Education and Communications, Ministry of Ecology and Environment, Beijing, 100029, China
| | - Jin-Te Zou
- College of Environment, Zhejiang University of Technology, Hangzhou, Zhejiang, 310014, China
| | - Feng He
- College of Environment, Zhejiang University of Technology, Hangzhou, Zhejiang, 310014, China.
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