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Trebuch LM, Timmer J, Graaf JVD, Janssen M, Fernandes TV. Making waves: How to clean surface water with photogranules. WATER RESEARCH 2024; 260:121875. [PMID: 38875855 DOI: 10.1016/j.watres.2024.121875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 05/11/2024] [Accepted: 06/02/2024] [Indexed: 06/16/2024]
Abstract
Global surface waters are in a bad ecological and chemical state, which has detrimental effects on entire ecosystems. To prevent further deterioration of ecosystems and ecosystem services, it is vital to minimize environmental pollution and come up with ways to keep surface water healthy and clean. Recently, photogranules have emerged as a promising platform for wastewater treatment to remove organic matter and nutrients with reduced or eliminated mechanical aeration, while also facilitating CO2 capture and production of various bioproducts. Photogranules are microbial aggregates of microalgae, cyanobacteria, and other non-phototrophic organisms that form dense spheroidic granules. Photogranules settle fast and can be easily retained in the treatment system, which allows increased amounts of water and wastewater to be treated. So far, photogranules have only been tested on various "high-strength" wastewaters but they might be an excellent choice for treatment of large volumes of polluted surface water as well. Here, we propose and tested for the first time photogranules on their effectiveness to remove nutrients from polluted surface water at unprecedented low concentrations (3.2 mg/L of nitrogen and 0.12 mg/L of phosphorous) and low hydraulic retention time (HRT = 1.5 h). Photogranules can successfully remove nitrogen (<0.6 mg/L, ∼80 % removal) and phosphorous (<0.01 mg/L, 90-95 % removal) to low levels in sequencing batch operation even without the need for pH control. Subjecting photogranules to surface water treatment conditions drastically changed their morphology. While, under "high-strength" conditions the photogranules were spherical, dense and defined, under polluted surface water conditions photogranules increased their surface area by forming fingers. However, this did not compromise their excellent settling properties. Finally, we discuss the future perspectives of photogranular technology for surface water treatment.
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Affiliation(s)
- Lukas M Trebuch
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Droevendaalsesteeg 10, 6708 PB, Wageningen, The Netherlands.
| | - Jolieke Timmer
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Droevendaalsesteeg 10, 6708 PB, Wageningen, The Netherlands
| | - Jan van de Graaf
- Waterboard De Dommel, Bosscheweg 56, 5283 WB, Boxtel, The Netherlands
| | - Marcel Janssen
- Bioprocess Engineering, AlgaePARC Wageningen University, P.O. Box 16, 6700 AA, Wageningen, The Netherlands
| | - Tânia V Fernandes
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Droevendaalsesteeg 10, 6708 PB, Wageningen, The Netherlands; IHE Delft Institute for Water Education, Westvest 7, 2611 AX Delft, The Netherlands; Environmental Technology, Wageningen University, PO Box 8129, 6700 EV Wageningen, The Netherlands
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2
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Galea-Outón S, Milferstedt K, Hamelin J. High methane potential of oxygenic photogranules decreases after starvation. BIORESOURCE TECHNOLOGY 2024; 406:130986. [PMID: 38908765 DOI: 10.1016/j.biortech.2024.130986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2024] [Revised: 06/14/2024] [Accepted: 06/14/2024] [Indexed: 06/24/2024]
Abstract
Oxygenic photogranules (OPG) are granular biofilms that can treat wastewater without external aeration, making it an advantage over activated sludge. Excess of OPG biomass can serve as energy source through anaerobic digestion. Two sequencing batch photoreactors were operated over 400 days to grow OPG. Biochemical methane potentials (BMP) were obtained from near-infrared spectroscopy. OPGs had an average BMP of 356 mL CH4·gVS-1, much higher than typical BMP from activated sludge. A partial least squares analysis could relate BMP with reactor operating conditions, like light regime, load or biomass concentration. Since organic load was the most influential parameter on BMP, three starvation experiments were set up. An average decrease of BMP by 18.4 % was observed. However, the unexpected growth of biomass during starvation resulted in a higher total methane volume. In conclusion, starvation reduces the BMP of OPGs but anaerobic digestion of OPG biomass remains a promising route for biomass valorization.
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Affiliation(s)
- Sandra Galea-Outón
- INRAE, Univ Montpellier, LBE, 102 Avenue des étangs, 11100 Narbonne, France
| | - Kim Milferstedt
- INRAE, Univ Montpellier, LBE, 102 Avenue des étangs, 11100 Narbonne, France
| | - Jérôme Hamelin
- INRAE, Univ Montpellier, LBE, 102 Avenue des étangs, 11100 Narbonne, France.
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3
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Doloman A, Sousa DZ. Mechanisms of microbial co-aggregation in mixed anaerobic cultures. Appl Microbiol Biotechnol 2024; 108:407. [PMID: 38963458 PMCID: PMC11224092 DOI: 10.1007/s00253-024-13246-8] [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: 05/02/2024] [Revised: 06/24/2024] [Accepted: 06/27/2024] [Indexed: 07/05/2024]
Abstract
Co-aggregation of anaerobic microorganisms into suspended microbial biofilms (aggregates) serves ecological and biotechnological functions. Tightly packed aggregates of metabolically interdependent bacteria and archaea play key roles in cycling of carbon and nitrogen. Additionally, in biotechnological applications, such as wastewater treatment, microbial aggregates provide a complete metabolic network to convert complex organic material. Currently, experimental data explaining the mechanisms behind microbial co-aggregation in anoxic environments is scarce and scattered across the literature. To what extent does this process resemble co-aggregation in aerobic environments? Does the limited availability of terminal electron acceptors drive mutualistic microbial relationships, contrary to the commensal relationships observed in oxygen-rich environments? And do co-aggregating bacteria and archaea, which depend on each other to harvest the bare minimum Gibbs energy from energy-poor substrates, use similar cellular mechanisms as those used by pathogenic bacteria that form biofilms? Here, we provide an overview of the current understanding of why and how mixed anaerobic microbial communities co-aggregate and discuss potential future scientific advancements that could improve the study of anaerobic suspended aggregates. KEY POINTS: • Metabolic dependency promotes aggregation of anaerobic bacteria and archaea • Flagella, pili, and adhesins play a role in the formation of anaerobic aggregates • Cyclic di-GMP/AMP signaling may trigger the polysaccharides production in anaerobes.
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Affiliation(s)
- Anna Doloman
- Laboratory of Microbiology, Wageningen University & Research, Stippeneng 4, 6708 WE, Wageningen, The Netherlands.
| | - Diana Z Sousa
- Laboratory of Microbiology, Wageningen University & Research, Stippeneng 4, 6708 WE, Wageningen, The Netherlands
- Centre for Living Technologies, Eindhoven-Wageningen-Utrecht Alliance, Princetonlaan 6, 3584 CB, Utrecht, The Netherlands
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4
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Zhong J, Tang L, Gao M, Wang S, Wang X. Beyond feast and famine: Cultivating hydrodynamic oxygenic photogranules with better performances under permanent feast regime. BIORESOURCE TECHNOLOGY 2024; 401:130752. [PMID: 38685514 DOI: 10.1016/j.biortech.2024.130752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Revised: 04/26/2024] [Accepted: 04/26/2024] [Indexed: 05/02/2024]
Abstract
Oxygenic photogranules (OPGs) are currently obtained in permanent famine or cyclic feast-famine regimes. Whether photogranulation occurs under a permanent feast regime and how these regimes impact OPGs are unknown. Herein, the three regimes, each applied in two replicate hydrodynamic reactors, were established by different feeding frequencies. Results showed that OPGs were successfully cultivated in all regimes after 24-36 days of photogranulation phases with similar microbial community functions, including filamentous gliding, extracellular polymeric substances production, and carbon/nitrogen metabolism. The OPGs were then operated under the same sequencing batch mode and all achieved efficient removal of chemical oxygen demand (>91 %), ammonium (>96 %), and total nitrogen (>76 %) after different adaptation periods (19-41 days). Notably, the permanent feast regime obtained OPGs with the best physicochemical properties, the shortest adaptation period, and the lowest effluent turbidity, thus representing a novel means of hydrodynamic cultivating OPGs with better performances for sustainable wastewater treatment.
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Affiliation(s)
- Jiewen Zhong
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Liaofan Tang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Mingming Gao
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Shuguang Wang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China; Weihai Research Institute of Industrial Technology of Shandong University, Weihai 264209, China
| | - Xinhua Wang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China.
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5
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Li J, Tang L, Zhang Y, Gao M, Wang S, Wang X. Hydrodynamic cultivation of aeration-free oxygenic photogranules is favored by sufficient amounts of organic carbon. BIORESOURCE TECHNOLOGY 2024; 401:130736. [PMID: 38670289 DOI: 10.1016/j.biortech.2024.130736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 04/09/2024] [Accepted: 04/23/2024] [Indexed: 04/28/2024]
Abstract
Oxygenic photogranules (OPGs) have great potential for the aeration-free treatment of various wastewater, however, the effects of wastewater carbon composition on OPGs remain unknown. This study investigated the hydrodynamic photogranulation in three types of wastewater with the same total carbon concentration but different inorganic/organic carbon compositions, each operated at two replicated reactors. Results showed that photogranulation failed in reactors fed with only inorganic carbon. In reactors with equal inorganic and organic carbon, loose-structured OPGs formed but then disintegrated. Comparatively, reactors treating organic carbon-based wastewater obtained regular and dense OPGs with better settleability, lower effluent turbidity, excellent structural stability, and higher carbon assimilation rate. Sufficient amounts of organic carbon were crucial for the formation and stability of OPGs as they promoted the secretion of extracellular polymeric substances (EPS) and the growth of filamentous cyanobacteria. This study provides a basis for the startup of OPGs process and facilitates its large-scale application.
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Affiliation(s)
- Junrong Li
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Liaofan Tang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Yuqing Zhang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Mingming Gao
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Shuguang Wang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China; Weihai Research Institute of Industrial Technology of Shandong University, Weihai 264209, China
| | - Xinhua Wang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China.
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6
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Lai JL, Li ZG, Han MW, Huang Y, Xi HL, Luo XG. Analysis of environmental biological effects and OBT accumulation potential of microalgae in freshwater systems exposed to tritium pollution. WATER RESEARCH 2024; 250:121013. [PMID: 38118252 DOI: 10.1016/j.watres.2023.121013] [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: 06/01/2023] [Revised: 12/07/2023] [Accepted: 12/10/2023] [Indexed: 12/22/2023]
Abstract
The ecological risk of tritiated wastewater into the environment has attracted much attention. Assessing the ecological risk of tritium-containing pollution is crucial by studying low-activity tritium exposure's environmental and biological effects on freshwater micro-environment and the enrichment potential of organically bound tritium (OBT) in microalgae and aquatic plants. The impact of tritium-contaminated wastewater on the microenvironment of freshwater systems was analyzed using microcosm experiments to simulate tritium pollution in freshwater systems. Low activity tritium pollution (105 Bq/L) induced differences in microbial abundance, with Proteobacteria, Bacteroidota, and Desulfobacterota occupying important ecological niches in the water system. Low activity tritium (105-107 Bq/L) did not affect the growth of microalgae and aquatic plants, but OBT was significantly enriched in microalgae and two aquatic plants (Pistia stratiotes, Spirodela polyrrhiza), with the enrichment coefficients of 2.08-3.39 and 1.71-2.13, respectively. At the transcriptional level, low-activity tritium (105 Bq/L) has the risk of interfering with gene expression in aquatic plants. Four dominant cyanobacterial strains (Leptolyngbya sp., Synechococcus elongatus, Nostoc sp., and Anabaena sp.) were isolated and demonstrated good environmental adaptability to tritium pollution. Environmental factors can modify the tritium accumulation potential in cyanobacteria and microalgae, theoretically enhancing food chain transfer.
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Affiliation(s)
- Jin-Long Lai
- School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, 621010, China; State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, China
| | - Zhan-Guo Li
- State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, China
| | - Meng-Wei Han
- State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, China
| | - Yan Huang
- School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, 621010, China
| | - Hai-Ling Xi
- State Key Laboratory of NBC Protection for Civilian, Beijing, 102205, China.
| | - Xue-Gang Luo
- School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, 621010, China.
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Zhang JT, Wang JX, Liu Y, Zhang Y, Wang JH, Chi ZY, Kong FT. Microalgal-bacterial biofilms for wastewater treatment: Operations, performances, mechanisms, and uncertainties. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 907:167974. [PMID: 37884155 DOI: 10.1016/j.scitotenv.2023.167974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 09/28/2023] [Accepted: 10/18/2023] [Indexed: 10/28/2023]
Abstract
Microalgal-bacterial biofilms have been increasingly considered of great potential in wastewater treatment due to the advantages of microalgal-bacterial synergistic pollutants removal/recovery, CO2 sequestration, and cost-effective biomass-water separation. However, such advantages may vary widely among different types of microalgal-bacterial biofilms, as the biofilms could be formed on different shapes and structures of attachment substratum, generating "false hope" for certain systems in large-scale wastewater treatment if the operating conditions and pollutants removal properties are evaluated based on the general term "microalgal-bacterial biofilm". This study, therefore, classified microalgal-bacterial biofilms into biofilms formed on 2D substratum, biofilms formed on 3D substratum, and biofilms formed without substratum (i.e. microalgal-bacterial granular sludge, MBGS). Biofilms formed on 2D substratum display higher microalgae fractions and nutrients removal efficiencies, while the adopted long hydraulic retention times were unacceptable for large-scale wastewater treatment. MBGS are featured with much lower microalgae fractions, most efficient pollutants removal, and acceptable retention times for realistic application, yet the feasibility of using natural sunlight should be further explored. 3D substratum systems display wide variations in operating conditions and pollutants removal properties because of diversified substratum shapes and structures. 2D and 3D substratum biofilms share more common in eukaryotic and prokaryotic microbial community structures, while MGBS biofilms are more enriched with microorganisms favoring EPS production, biofilm formation, and denitrification. The specific roles of stratified extracellular polymeric substances (EPS) in nutrients adsorption and condensation still require in-depth exploration. Nutrients removal uncertainties caused by microalgal-bacterial synergy decoupling under insufficient illumination, limited microbial community control, and possible greenhouse gas emission exacerbation arising from microalgal N2O generation were also indicated. This review is helpful for revealing the true potential of applying various microalgal-bacterial biofilms in large-scale wastewater treatment, and will provoke some insights on the challenges to the ideal state of synergistic pollutants reclamation and carbon neutrality via microalgal-bacterial interactions.
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Affiliation(s)
- Jing-Tian Zhang
- School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China
| | - Jian-Xia Wang
- School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China
| | - Yang Liu
- School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China
| | - Ying Zhang
- School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China
| | - Jing-Han Wang
- School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China; Key Laboratory of Environment Controlled Aquaculture, Dalian Ocean University, Dalian 116023, PR China.
| | - Zhan-You Chi
- School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China
| | - Fan-Tao Kong
- School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China
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Kong L, Feng Y, Du W, Zheng R, Sun J, Rong K, Sun W, Liu S. Cross-Feeding between Filamentous Cyanobacteria and Symbiotic Bacteria Favors Rapid Photogranulation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:16953-16963. [PMID: 37886803 DOI: 10.1021/acs.est.3c04867] [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] [Indexed: 10/28/2023]
Abstract
Photogranules are dense algal-bacterial aggregates used in aeration-free and carbon-negative wastewater treatment, wherein filamentous cyanobacteria (FC) are essential components. However, little is known about the functional role of symbiotic bacteria in photogranulation. Herein, we combined cyanobacterial isolation, reactor operation, and multiomics analysis to investigate the cyanobacterial-bacterial interaction during photogranulation. The addition of FC to the inoculated sludge achieved a 1.4-fold higher granule size than the control, and the aggregation capacity of FC-dominant photogranules was closely related to the extracellular polysaccharide (PS) concentration (R = 0.86). Importantly, we found that cross-feeding between FC and symbiotic bacteria for macromolecular PS synthesis is at the heart of photogranulation and substantially enhanced the granular stability. Chloroflexi-affiliated bacteria intertwined with FC throughout the photogranules and promoted PS biosynthesis using the partial nucleotide sugars produced by FC. Proteobacteria-affiliated bacteria were spatially close to FC, and highly expressed genes for vitamin B1 and B12 synthesis, contributing the necessary cofactors to promote FC proliferation. In addition, Bacteroidetes-affiliated bacteria degraded FC-derived carbohydrates and influenced granules development. Our metabolic characterization identified the functional role of symbiotic bacteria of FC during photogranulation and shed light on the critical cyanobacterial-bacterial interactions in photogranules from the viewpoint of cross-feeding.
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Affiliation(s)
- Lingrui Kong
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
| | - Yiming Feng
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
| | - Wenran Du
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
- School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Ru Zheng
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
| | - Jingqi Sun
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
| | - Kaiyu Rong
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
| | - Weiling Sun
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
| | - Sitong Liu
- Department of Environmental Engineering, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- Key Laboratory of Water and Sediment Sciences, Ministry of Education of China, Peking University, Beijing 100871, China
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Zhi M, Zhao Y, Zeng X, Maddela NR, Xiao Y, Chen Y, Prasad R, Zhou Z. Filamentous cyanobacteria and hydrophobic protein in extracellular polymeric substances facilitate algae-bacteria aggregation during partial nitrification. Int J Biol Macromol 2023; 251:126379. [PMID: 37595699 DOI: 10.1016/j.ijbiomac.2023.126379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 07/08/2023] [Accepted: 08/15/2023] [Indexed: 08/20/2023]
Abstract
In algae-bacteria symbiotic wastewater treatment, the excellent settling performance of algae-bacteria aggregates is critical for biomass separation and recovery. Here, the composition of extracellular polymeric substances (EPS), microbial profiles, and functional genes of algae-bacteria aggregates were investigated at different solid retention times (SRTs) (10, 20, and 40 d) during partial nitrification in photo sequencing bioreactors (PSBRs). Results showed that SRTs greatly influenced the nitrogen transformation and the formation and morphological structure of algae-bacteria aggregates. The highest nitrite accumulation, the largest particle size (~1.54 mm) and the best settling performance were observed for the algae-bacteria aggregates in the PSBR with an SRT of 10 d, where the abundant occurrence of filamentous cyanobacteria with the highest ratio of chlorophyll a/b and the lowest EPS amount with the highest protein-to-polysaccharide ratio were observed. In particular, the EPS at 10 d of SRT contained a higher amount of protein-related hydrophobic groups and a lower ratio of α-helix/(β-sheet + random coil), indicating a looser protein structure, which might facilitate the formation and stabilization of algae-bacteria aggregates. Moreover, algal-bacterial aggregation greatly depended on the composition and evolution of filamentous cyanobacteria (unclassified _o__Oscillatoriales and Phormidium accounted for 56.29 % of the identified algae at SRT 10 d). The metagenomic analysis further revealed that functional genes related to amino acid metabolism (e.g., genes of phenylalanine, tyrosine, and tryptophan biosynthesis) were expressed at high levels within 10 d of SRT. Overall, this study demonstrates the influence of EPS structures and filamentous cyanobacteria on algae-bacteria aggregation and reveals the biological mechanisms driving photogranule structure and function.
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Affiliation(s)
- Mei Zhi
- College of Resources and Environment, Southwest University, Chongqing 400715, China; Chongqing Engineering Research Center of Rural Cleaner Production, Chongqing 400715, China
| | - Yiying Zhao
- College of Resources and Environment, Southwest University, Chongqing 400715, China
| | - Xinyu Zeng
- College of Resources and Environment, Southwest University, Chongqing 400715, China
| | - Naga Raju Maddela
- Departamento de Ciencias Biológicas, Facultad de Ciencias de la Salud, Universidad Técnica de Manabí, Portoviejo 130105, Ecuador
| | - Yeyuan Xiao
- Department of Civil and Environmental Engineering, Shantou University, Shantou 515063, China
| | - Yucheng Chen
- College of Resources and Environment, Southwest University, Chongqing 400715, China; Chongqing Engineering Research Center of Rural Cleaner Production, Chongqing 400715, China
| | - Ram Prasad
- Department of Botany, Mahatma Gandhi Central University, Motihari, Bihar 845401, India.
| | - Zhongbo Zhou
- College of Resources and Environment, Southwest University, Chongqing 400715, China; Chongqing Engineering Research Center of Rural Cleaner Production, Chongqing 400715, China.
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Wu B, Ran T, Liu S, Li Q, Cui X, Zhou Y. Biofilm bioactivity affects nitrogen metabolism in a push-flow microalgae-bacteria biofilm reactor during aeration-free greywater treatment. WATER RESEARCH 2023; 244:120461. [PMID: 37639992 DOI: 10.1016/j.watres.2023.120461] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 07/30/2023] [Accepted: 08/07/2023] [Indexed: 08/31/2023]
Abstract
Non-aeration microalgae-bacteria biofilm has attracted increasing interest for its application in low cost wastewater treatment. However, it is unclear the quantified biofilm characteristics dynamics and how biofilm bioactivity affects performance and nitrogen metabolisms during wastewater treatment. In this work, a push-flow microalgae-bacteria biofilm reactor (PF-MBBfR) was developed for aeration-free greywater treatment. Comparatively, organic loading at 1.27 ± 0.10 kg COD/(m3⋅d) gave the highest biofilm concentration, density, specific oxygen generation (SOGR) and consumption rates (SOCR), and pollutants removal rates. Contributed to low residual linear alkylbenzene sulfonates and bioactivity, reactor downstream showed low bacteria and protein concentrations and SOCR (12.8 mg O2/g TSS·h), but high microalgae, carbohydrate, biofilm density, SOGR (49.4 mg O2/g TSS·h) and pollutants removal rates. Dissolved organic nitrogen (DON) showed higher molecular weight, CHONS and fraction with 4 atoms of N in reactor upstream. Most of nitrogen was fixed to newly synthesized biomass during assimilation process by related functional enzymes, minor contributed to denitrification due to low N2 emission. High nitrogen assimilation by microalgae showed high SOGR, which favored efficient multiple pollutants removal and reduced DON emission. Our findings favor the practical application of PF-MBBfR based on biofilm bioactivity, enhancing efficiency and reducing DON emission for low- energy-input wastewater treatment.
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Affiliation(s)
- Beibei Wu
- College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China
| | - Ting Ran
- College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China
| | - Sibei Liu
- College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China
| | - Qian Li
- College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China
| | - Xiaocai Cui
- College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China
| | - Yun Zhou
- College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China.
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11
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Joosten ED, Hamelin J, Milferstedt K. Initial type and abundance of cyanobacteria determine morphotype development of phototrophic ecosystems. FEMS Microbiol Ecol 2023; 99:fiad099. [PMID: 37653452 DOI: 10.1093/femsec/fiad099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 07/24/2023] [Accepted: 08/28/2023] [Indexed: 09/02/2023] Open
Abstract
Phototrophic aggregates containing filamentous cyanobacteria occur naturally, for example, as cryoconite on glaciers and microbialites in fresh or marine waters, but their formation is not fully understood. Laboratory models are now available to reproduce aggregation, that is, the formation of different morphotypes like hemispheroids, microbial mats or sphere-like aggregates we call photogranules. In the model, activated sludge as starting matrix is transformed into aggregates enclosed by a phototrophic layer of growing cyanobacteria. These cyanobacteria were either enriched from the matrix or we added them intentionally. We hypothesize that the resulting morphotype depends on the type and concentration of the added cyanobacteria. When cyanobacteria from mature photogranules were added to activated sludge, photogranulation was not observed, but microbial mats were formed. Photogranulation of sludge could be promoted when adding sufficient quantities of cyanobacterial strains that form clumps when grown as isolates. The cyanobacteria putatively responsible for photogranulation were undetectable or only present in low abundance in the final communities of photogranules, which were always dominated by mat-forming cyanobacteria. We suggest that, in a temporal succession, the ecosystem engineer initiating photogranulation eventually disappears, leaving behind its structural legacy. We conclude that understanding phototrophic aggregate formation requires considering the initial succession stages of the ecosystem development.
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Affiliation(s)
| | - Jérôme Hamelin
- INRAE, Univ Montpellier, LBE, 102 Avenue des Etangs, 11100, Narbonne, France
| | - Kim Milferstedt
- INRAE, Univ Montpellier, LBE, 102 Avenue des Etangs, 11100, Narbonne, France
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12
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Zhang X, Ji B, Tian J, Liu Y. Development, performance and microbial community analysis of a continuous-flow microalgal-bacterial biofilm photoreactor for municipal wastewater treatment. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 338:117770. [PMID: 36965425 DOI: 10.1016/j.jenvman.2023.117770] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2023] [Revised: 03/15/2023] [Accepted: 03/18/2023] [Indexed: 06/18/2023]
Abstract
This work reported the development, performance and microbial community of microalgal-bacterial biofilms cultivated in a continuous-flow photoreactor for municipal wastewater treatment under various conditions. Results showed that microalgal-bacterial biofilms were successfully developed at a HRT of 9 h without external aeration, with a biofilm concentration of around 4690 mg/L being achieved in the steady-state. It was found that further increase of HRT to 12 h did not improve the overall accumulation of biofilm, whereas the growth of microalgae in biofilms was faster than bacteria in the initial stage, indicated by an increased chlorophyll-a&b content in biofilms. After which, the chlorophyll-a&b content in biofilms gradually stabilized at the level comparable with the seed, suggesting that there was a balanced distribution of microalgae and bacteria in biofilms. About 90% of TOC, 71.4% of total nitrogen and 72.6% of phosphorus were removed by microalgal-bacterial biofilms mainly through assimilation in the steady-state photoreactor run at the HRT of 12 h with external aeration. The community analysis further revealed that Cyanobacteria and Chloroflexi were the main components, while Chlorophyta appeared to be the dominant eukaryotic algal community in biofilms. This study could offer new insights into the development of microalgal-bacterial biofilms in a continuous-flow photoreactor for sustainable low-carbon municipal wastewater treatment.
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Affiliation(s)
- Xiaoyuan Zhang
- College of Environmental Science and Engineering, Nankai University, Tianjin, 300350, China; Advanced Environmental Biotechnology Centre, Nanyang Environment & Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore, 637141, Singapore.
| | - Bin Ji
- Department of Water and Wastewater Engineering, School of Urban Construction, Wuhan University of Science and Technology, Wuhan, 430065, China
| | - Junli Tian
- College of Environmental Science and Engineering, Nankai University, Tianjin, 300350, China
| | - Yu Liu
- Advanced Environmental Biotechnology Centre, Nanyang Environment & Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore, 637141, Singapore; School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore.
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13
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Sorokovikova E, Tikhonova I, Evseev P, Krasnopeev A, Khanaev I, Potapov S, Gladkikh A, Nebesnykh I, Belykh O. Limnofasciculus baicalensis gen. et sp. nov. (Coleofasciculaceae, Coleofasciculales): A New Genus of Cyanobacteria Isolated from Sponge Fouling in Lake Baikal, Russia. Microorganisms 2023; 11:1779. [PMID: 37512951 PMCID: PMC10385159 DOI: 10.3390/microorganisms11071779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 07/06/2023] [Accepted: 07/07/2023] [Indexed: 07/30/2023] Open
Abstract
The proliferation of benthic cyanobacteria has been observed in Lake Baikal since 2011 and is a vivid manifestation of the ecological crisis occurring in the littoral zone. The cyanobacterium Symplocastrum sp. has formed massive fouling on all types of benthic substrates, including endemic Baikal sponges. The strain BBK-W-15 (=IPPAS B-2062T), which was isolated from sponge fouling in 2015, was used for further taxonomic determination. A polyphasic approach revealed that it is a cryptic taxon of cyanobacteria. Morphological evaluation of the strain indicated the presence of cylindrical filaments with isodiametric cells enclosed in individual sheaths and coleodesmoid false branching. Strain ultrastructure (fascicular thylakoids and type C cell division) is characteristic of the Microcoleaceae and Coleofasciculaceae families. An integrated analysis that included 16S rRNA gene phylogeny, conserved protein phylogeny and whole-genome comparisons indicated the unique position of BBK-W-15, thus supporting the proposed delineation of the new genus Limnofasciculus. Through characterisation by morphology, 16S, ITS and genomic analysis, a new cyanobacterium of the family Coleofasciculaceae Limnofasciculus baicalensis gen. et sp. nov. was described.
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Affiliation(s)
- Ekaterina Sorokovikova
- Limnological Institute of the Siberian Branch of the Russian Academy of Sciences, 3 Ulan-Batorskaya Str., Irkutsk 664033, Russia
| | - Irina Tikhonova
- Limnological Institute of the Siberian Branch of the Russian Academy of Sciences, 3 Ulan-Batorskaya Str., Irkutsk 664033, Russia
| | - Peter Evseev
- Limnological Institute of the Siberian Branch of the Russian Academy of Sciences, 3 Ulan-Batorskaya Str., Irkutsk 664033, Russia
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, 16/10 Miklukho-Maklaya Str., GSP-7, Moscow 117997, Russia
| | - Andrey Krasnopeev
- Limnological Institute of the Siberian Branch of the Russian Academy of Sciences, 3 Ulan-Batorskaya Str., Irkutsk 664033, Russia
| | - Igor Khanaev
- Limnological Institute of the Siberian Branch of the Russian Academy of Sciences, 3 Ulan-Batorskaya Str., Irkutsk 664033, Russia
| | - Sergey Potapov
- Limnological Institute of the Siberian Branch of the Russian Academy of Sciences, 3 Ulan-Batorskaya Str., Irkutsk 664033, Russia
| | - Anna Gladkikh
- Saint-Petersburg Pasteur Institute, 14 Mira Str., Saint-Petersburg 197101, Russia
| | - Ivan Nebesnykh
- Limnological Institute of the Siberian Branch of the Russian Academy of Sciences, 3 Ulan-Batorskaya Str., Irkutsk 664033, Russia
| | - Olga Belykh
- Limnological Institute of the Siberian Branch of the Russian Academy of Sciences, 3 Ulan-Batorskaya Str., Irkutsk 664033, Russia
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Russo F, Tenore A, Mattei MR, Frunzo L. A Mathematical Study of Metal Biosorption on Algal-Bacterial Granular Biofilms. Bull Math Biol 2023; 85:63. [PMID: 37269488 DOI: 10.1007/s11538-023-01168-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 05/16/2023] [Indexed: 06/05/2023]
Abstract
A multiscale mathematical model describing the metals biosorption on algal-bacterial photogranules within a sequencing batch reactor (SBR) is presented. The model is based on systems of partial differential equations (PDEs) derived from mass conservation principles on a spherical free boundary domain with radial symmetry. Hyperbolic PDEs account for the dynamics of sessile species and their free sorption sites, where metals are adsorbed. Parabolic PDEs govern the diffusion, conversion and adsorption of nutrients and metals. The dual effect of metals on photogranule ecology is also modelled: metal stimulates the production of EPS by sessile species and negatively affects the metabolic activities of microbial species. Accordingly, a stimulation term for EPS production and an inhibition term for metal are included in all microbial kinetics. The formation and evolution of the granule domain are governed by an ordinary differential equation with a vanishing initial value, accounting for microbial growth, attachment and detachment phenomena. The model is completed with systems of impulsive differential equations describing the evolution of dissolved substrates, metals, and planktonic and detached biomasses within the granular-based SBR. The model is integrated numerically to examine the role of the microbial species and EPS in the adsorption process, and the effect of metal concentration and adsorption properties of biofilm components on the metal removal. Numerical results show an accurate description of the photogranules evolution and ecology and confirm the applicability of algal-bacterial photogranule technology for metal-rich wastewater treatment.
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Affiliation(s)
- Fabiana Russo
- Department of Mathematics, Temple University, 1805 N Broad St, Philadelphia, PA, 19122, USA
- Department of Mathematics and Applications "Renato Caccioppoli", University of Naples Federico II, Via Cintia, Monte S. Angelo, 80126, Naples, Italy
| | - Alberto Tenore
- Department of Mathematics and Applications "Renato Caccioppoli", University of Naples Federico II, Via Cintia, Monte S. Angelo, 80126, Naples, Italy
| | - Maria Rosaria Mattei
- Department of Mathematics and Applications "Renato Caccioppoli", University of Naples Federico II, Via Cintia, Monte S. Angelo, 80126, Naples, Italy.
| | - Luigi Frunzo
- Department of Mathematics and Applications "Renato Caccioppoli", University of Naples Federico II, Via Cintia, Monte S. Angelo, 80126, Naples, Italy
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15
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Pfreundt U, Słomka J, Schneider G, Sengupta A, Carrara F, Fernandez V, Ackermann M, Stocker R. Controlled motility in the cyanobacterium Trichodesmium regulates aggregate architecture. Science 2023; 380:830-835. [PMID: 37228200 DOI: 10.1126/science.adf2753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 04/25/2023] [Indexed: 05/27/2023]
Abstract
The ocean's nitrogen is largely fixed by cyanobacteria, including Trichodesmium, which forms aggregates comprising hundreds of filaments arranged in organized architectures. Aggregates often form upon exposure to stress and have ecological and biophysical characteristics that differ from those of single filaments. Here, we report that Trichodesmium aggregates can rapidly modulate their shape, responding within minutes to changes in environmental conditions. Combining video microscopy and mathematical modeling, we discovered that this reorganization is mediated by "smart reversals" wherein gliding filaments reverse when their overlap with other filaments diminishes. By regulating smart reversals, filaments control aggregate architecture without central coordination. We propose that the modulation of gliding motility at the single-filament level is a determinant of Trichodesmium's aggregation behavior and ultimately of its biogeochemical role in the ocean.
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Affiliation(s)
- Ulrike Pfreundt
- Institute of Environmental Engineering, Department of Civil, Environmental and Geomatic Engineering, ETH Zurich, Zürich, Switzerland
| | - Jonasz Słomka
- Institute of Environmental Engineering, Department of Civil, Environmental and Geomatic Engineering, ETH Zurich, Zürich, Switzerland
| | - Giulia Schneider
- Institute of Environmental Engineering, Department of Civil, Environmental and Geomatic Engineering, ETH Zurich, Zürich, Switzerland
| | - Anupam Sengupta
- Physics of Living Matter, Department of Physics and Materials Science, University of Luxembourg, Luxembourg City, Grand Duchy of Luxembourg
| | - Francesco Carrara
- Institute of Environmental Engineering, Department of Civil, Environmental and Geomatic Engineering, ETH Zurich, Zürich, Switzerland
| | - Vicente Fernandez
- Institute of Environmental Engineering, Department of Civil, Environmental and Geomatic Engineering, ETH Zurich, Zürich, Switzerland
| | - Martin Ackermann
- Department of Environmental Systems Sciences, Microbial Systems Ecology Group, Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich, Zürich, Switzerland
- Department of Environmental Microbiology, Eawag: Swiss Federal Institute of Aquatic Sciences, Dübendorf, Switzerland
| | - Roman Stocker
- Institute of Environmental Engineering, Department of Civil, Environmental and Geomatic Engineering, ETH Zurich, Zürich, Switzerland
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16
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Lee HE, Lee JH, Park SM, Kim DG. Symbiotic relationship between filamentous algae ( Halomicronema sp.) and extracellular polymeric substance-producing algae ( Chlamydomonas sp.) through biomimetic simulation of natural algal mats. Front Microbiol 2023; 14:1176069. [PMID: 37293230 PMCID: PMC10244577 DOI: 10.3389/fmicb.2023.1176069] [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: 02/28/2023] [Accepted: 05/03/2023] [Indexed: 06/10/2023] Open
Abstract
To lower the cost of biomass harvesting, the growth of natural biofilm is considered to be an optimal alternative to microalgae aggregation. This study investigated algal mats that naturally agglomerate into a lump and float on water surfaces. Halomicronema sp., a filamentous cyanobacterium with high cell aggregation and adhesion to substrates, and Chlamydomonas sp., which grows rapidly and produces high extracellular polymeric substances (EPS) in certain environments, are the main microalgae that make up selected mats through next-generation sequencing analysis. These two species play a major role in the formation of solid mats, and showed a symbiotic relationship as the medium and nutritional source, particularly owing to the large amount of EPS formed by the reaction between EPS and calcium ions through zeta potential and Fourier-transform infrared spectroscopy analysis. This led to the formation of an ecological biomimetic algal mat (BAM) that mimics the natural algal mat system, and this is a way to reduce costs in the biomass production process as there is no separate treatment process for harvesting.
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Affiliation(s)
- Ha Eun Lee
- LED Agri-bio Fusion Technology Research Center, Jeonbuk National University, Iksan-si, Jeollabuk-do, Republic of Korea
| | - Jun Ho Lee
- Department of Agricultural Chemistry, Jeonbuk National University, Jeonju-si, Jeollabuk-do, Republic of Korea
| | - Seung Moon Park
- Department of Bioenvironmental Chemistry, Jeonbuk National University, Jeonju-si, Jeollabuk-do, Republic of Korea
| | - Dae Geun Kim
- LED Agri-bio Fusion Technology Research Center, Jeonbuk National University, Iksan-si, Jeollabuk-do, Republic of Korea
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17
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Biliani SE, Manariotis ID. Sustainable treatment of primary and secondary effluent by algal-bacterial flocculent biomass in raceway ponds. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 343:118167. [PMID: 37229856 DOI: 10.1016/j.jenvman.2023.118167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 05/04/2023] [Accepted: 05/11/2023] [Indexed: 05/27/2023]
Abstract
Two 5.5-L raceway open ponds were used to evaluate the removal of organic material and nutrients from wastewater. Algal-bacterial flocs were placed in the ponds to treat primary and secondary effluent. The organic loading rate ranged from 29 to 95 and 9 to 38 g sCOD m-3 d-1 for the reactor fed with primary and secondary effluent, respectively. The hydraulic retention time (HRT) gradually decreased in both reactors from 5.5 to 2.2 d during a period of 21 days, and after that, both reactors operated at an HRT of 1.1 d. A high biomass concentration of around 2.2 g L-1 was sustained using primary and secondary effluent after 130 days. The biomass, developed with both substrates was very active and completely removed organic material and nutrients in less than 12 h. The algal-bacteria biomass had excellent settling properties and could settle in less than 10 min.
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Affiliation(s)
- Styliani E Biliani
- Environmental Engineering Laboratory, Department of Civil Engineering, University of Patras, 265 04, Patras, Greece
| | - Ioannis D Manariotis
- Environmental Engineering Laboratory, Department of Civil Engineering, University of Patras, 265 04, Patras, Greece.
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18
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Trebuch LM, Sohier J, Altenburg S, Oyserman BO, Pronk M, Janssen M, Vet LEM, Wijffels RH, Fernandes TV. Enhancing phosphorus removal of photogranules by incorporating polyphosphate accumulating organisms. WATER RESEARCH 2023; 235:119748. [PMID: 36944303 DOI: 10.1016/j.watres.2023.119748] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 01/21/2023] [Accepted: 02/12/2023] [Indexed: 06/18/2023]
Abstract
Photogranules are a novel wastewater treatment technology that can utilize the sun's energy to treat water with lower energy input and have great potential for nutrient recovery applications. They have been proven to efficiently remove nitrogen and carbon but show lower conversion rates for phosphorus compared to established treatment systems, such as aerobic granular sludge. In this study, we successfully introduced polyphosphate accumulating organisms (PAOs) to an established photogranular culture. We operated photobioreactors in sequencing batch mode with six cycles per day and alternating anaerobic (dark) and aerobic (light) phases. We were able to increase phosphorus removal/recovery by 6 times from 5.4 to 30 mg/L/d while maintaining similar nitrogen and carbon removal compared to photogranules without PAOs. To maintain PAOs activity, alternating anaerobic feast and aerobic famine conditions were required. In future applications, where aerobic conditions are dependent on in-situ oxygenation via photosynthesis, the process will rely on sunlight availability. Therefore, we investigated the feasibility of the process under diurnal cycles with a 12-h anaerobic phase during nighttime and six short cycles during the 12 h daytime. The 12-h anaerobic phase had no adverse effect on the PAOs and phototrophs. Due to the extension of one anaerobic phase to 12 h the six aerobic phases were shortened by 47% and consequently decreased the light hours per day. This resulted in a decrease of phototrophs, which reduced nitrogen removal and biomass productivity up to 30%. Finally, we discuss and suggest strategies to apply PAO-enriched photogranules at large-scale.
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Affiliation(s)
- Lukas M Trebuch
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Droevendaalsesteeg 10, 6708 PB, Wageningen, The Netherlands; Bioprocess Engineering, AlgaePARC Wageningen University, P.O. Box 16, 6700 AA, Wageningen, The Netherlands.
| | - Jasper Sohier
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Droevendaalsesteeg 10, 6708 PB, Wageningen, The Netherlands
| | - Sido Altenburg
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Droevendaalsesteeg 10, 6708 PB, Wageningen, The Netherlands
| | - Ben O Oyserman
- Department of Microbial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Droevendaalsesteeg 10, 6708 PB, Wageningen, The Netherlands; Bioinformatics Group, Wageningen University, Wageningen, The Netherlands
| | - Mario Pronk
- Department of Biotechnology, Delft University of Technology, Van der Maasweg 9, Delft, 2629 HZ, The Netherlands; Royal HaskoningDHV, Laan1914 35, Amersfoort, 3800 AL, The Netherlands
| | - Marcel Janssen
- Bioprocess Engineering, AlgaePARC Wageningen University, P.O. Box 16, 6700 AA, Wageningen, The Netherlands
| | - Louise E M Vet
- Department of Terrestrial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Droevendaalsesteeg 10, 6708 PB, Wageningen, The Netherlands
| | - René H Wijffels
- Bioprocess Engineering, AlgaePARC Wageningen University, P.O. Box 16, 6700 AA, Wageningen, The Netherlands; Faculty of Biosciences and Aquaculture, Nord University, N-8049, Bodø, Norway
| | - Tânia V Fernandes
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Droevendaalsesteeg 10, 6708 PB, Wageningen, The Netherlands
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19
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Ashoor S, Jun SH, Ko HD, Lee J, Hamelin J, Milferstedt K, Na JG. Polyhydroxybutyrate Production from Methane and Carbon Dioxide by a Syntrophic Consortium of Methanotrophs with Oxygenic Photogranules without an External Oxygen Supply. Microorganisms 2023; 11:1110. [PMID: 37317084 DOI: 10.3390/microorganisms11051110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2023] [Revised: 04/16/2023] [Accepted: 04/22/2023] [Indexed: 06/16/2023] Open
Abstract
Here, a syntrophic process was developed to produce polyhydroxy-β-butyrate (PHB) from a gas stream containing CH4 and CO2 without an external oxygen supply using a combination of methanotrophs with the community of oxygenic photogranules (OPGs). The co-culture features of Methylomonas sp. DH-1 and Methylosinus trichosporium OB3b were evaluated under carbon-rich and carbon-lean conditions. The critical role of O2 in the syntrophy was confirmed through the sequencing of 16S rRNA gene fragments. Based on their carbon consumption rates and the adaptation to a poor environment, M. trichosporium OB3b with OPGs was selected for methane conversion and PHB production. Nitrogen limitation stimulated PHB accumulation in the methanotroph but hindered the growth of the syntrophic consortium. At 2.9 mM of the nitrogen source, 1.13 g/L of biomass and 83.0 mg/L of PHB could be obtained from simulated biogas. These results demonstrate that syntrophy has the potential to convert greenhouse gases into valuable products efficiently.
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Affiliation(s)
- Selim Ashoor
- Department of Agricultural Microbiology, Faculty of Agriculture, Ain Shams University, Hadayek Shoubra, Cairo 11241, Egypt
- Department of Chemical and Biomolecular Engineering, Sogang University, Seoul 04107, Republic of Korea
| | - Seong-Hoon Jun
- Department of Chemical and Biomolecular Engineering, Sogang University, Seoul 04107, Republic of Korea
| | - Han Do Ko
- Department of Chemical and Biomolecular Engineering, Sogang University, Seoul 04107, Republic of Korea
| | - Jinwon Lee
- Department of Chemical and Biomolecular Engineering, Sogang University, Seoul 04107, Republic of Korea
| | - Jérôme Hamelin
- INRAE, University of Montpellier, LBE, 102 Avenue des Etangs, 11100 Narbonne, France
| | - Kim Milferstedt
- INRAE, University of Montpellier, LBE, 102 Avenue des Etangs, 11100 Narbonne, France
| | - Jeong-Geol Na
- Department of Chemical and Biomolecular Engineering, Sogang University, Seoul 04107, Republic of Korea
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20
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Cremin K, Duxbury SJN, Rosko J, Soyer OS. Formation and emergent dynamics of spatially organized microbial systems. Interface Focus 2023; 13:20220062. [PMID: 36789239 PMCID: PMC9912014 DOI: 10.1098/rsfs.2022.0062] [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: 10/25/2022] [Accepted: 12/19/2022] [Indexed: 02/12/2023] Open
Abstract
Spatial organization is the norm rather than the exception in the microbial world. While the study of microbial physiology has been dominated by studies in well-mixed cultures, there is now increasing interest in understanding the role of spatial organization in microbial physiology, coexistence and evolution. Where studied, spatial organization has been shown to influence all three of these aspects. In this mini review and perspective article, we emphasize that the dynamics within spatially organized microbial systems (SOMS) are governed by feedbacks between local physico-chemical conditions, cell physiology and movement, and evolution. These feedbacks can give rise to emergent dynamics, which need to be studied through a combination of spatio-temporal measurements and mathematical models. We highlight the initial formation of SOMS and their emergent dynamics as two open areas of investigation for future studies. These studies will benefit from the development of model systems that can mimic natural ones in terms of species composition and spatial structure.
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Affiliation(s)
- Kelsey Cremin
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
| | | | - Jerko Rosko
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
| | - Orkun S. Soyer
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
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21
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Trebuch LM, Bourceau OM, Vaessen SMF, Neu TR, Janssen M, de Beer D, Vet LEM, Wijffels RH, Fernandes TV. High resolution functional analysis and community structure of photogranules. THE ISME JOURNAL 2023; 17:870-879. [PMID: 36997724 DOI: 10.1038/s41396-023-01394-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 02/28/2023] [Accepted: 03/03/2023] [Indexed: 03/31/2023]
Abstract
AbstractPhotogranules are spherical aggregates formed of complex phototrophic ecosystems with potential for “aeration-free” wastewater treatment. Photogranules from a sequencing batch reactor were investigated by fluorescence microscopy, 16S/18S rRNA gene amplicon sequencing, microsensors, and stable- and radioisotope incubations to determine the granules’ composition, nutrient distribution, and light, carbon, and nitrogen budgets. The photogranules were biologically and chemically stratified, with filamentous cyanobacteria arranged in discrete layers and forming a scaffold to which other organisms were attached. Oxygen, nitrate, and light gradients were also detectable. Photosynthetic activity and nitrification were both predominantly restricted to the outer 500 µm, but while photosynthesis was relatively insensitive to the oxygen and nutrient (ammonium, phosphate, acetate) concentrations tested, nitrification was highly sensitive. Oxygen was cycled internally, with oxygen produced through photosynthesis rapidly consumed by aerobic respiration and nitrification. Oxygen production and consumption were well balanced. Similarly, nitrogen was cycled through paired nitrification and denitrification, and carbon was exchanged through photosynthesis and respiration. Our findings highlight that photogranules are complete, complex ecosystems with multiple linked nutrient cycles and will aid engineering decisions in photogranular wastewater treatment.
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22
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Biliani SE, Manariotis ID. Wastewater treatment by high density algal flocs for nutrient removal and biomass production. JOURNAL OF APPLIED PHYCOLOGY 2023; 35:1237-1250. [PMID: 37249918 PMCID: PMC9990567 DOI: 10.1007/s10811-023-02931-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 02/15/2023] [Accepted: 02/15/2023] [Indexed: 05/31/2023]
Abstract
The present work investigated the efficiency of algal flocs biomass for the treatment of primary and secondary effluent in static and mixing conditions under different hydraulic retention time (HRT). Primary effluent fed cultures created a high-density biomass of 2.8 and 3.8 g L-1 under static and mixing conditions, respectively. Secondary effluent was more effective in order to create even higher density biomass of 7.8 and 6 g L-1 under static and mixing conditions, respectively. The algal floc biomass developed was quite effective for organic matter and nutrient removal. Primary effluent fed cultures seemed to be more efficient for chemical oxygen demand (COD) and ammonia nitrogen removal, while secondary effluent fed cultures for nitrates removal. At an HRT of 8 days using primary effluent, the removal of COD, ammonia nitrogen and total phosphorus was 86.2, 100 and 97.4%, respectively. The cultures fed with secondary effluent, even at low HRT of 1.2 days, achieved removals of 88.4, 77.5, 100 and 98.6% for COD, nitrates, ammonia, and total phosphorus, respectively. Supplementary Information The online version contains supplementary material available at 10.1007/s10811-023-02931-2.
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Affiliation(s)
- Styliani E. Biliani
- Environmental Engineering Laboratory, Department of Civil Engineering, University of Patras, 26504 Rio, Greece
| | - Ioannis D. Manariotis
- Environmental Engineering Laboratory, Department of Civil Engineering, University of Patras, 26504 Rio, Greece
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23
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Wang S, Zhang Y, Ge H, Hou H, Zhang H, Pi K. Cultivation of algal-bacterial granular sludge and degradation characteristics of tetracycline. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2023; 95:e10846. [PMID: 36789451 DOI: 10.1002/wer.10846] [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: 07/27/2022] [Revised: 01/28/2023] [Accepted: 02/11/2023] [Indexed: 06/18/2023]
Abstract
Due to the increasing use of antibiotics, tetracycline was frequently detected in wastewater. As a novel technology, algal-bacterial granular sludge process is expected to be widely used in wastewater treatment. However, the degradation effect of tetracycline by algal-bacterial granular sludge process and its degradation path is still unknown. In this study, mature and stable algal-bacterial granular sludge was cultured and the degradation of tetracycline by it was investigated. The results showed that the removal amount of 1-25 mg/L tetracycline by algal-bacterial granular sludge was 0.09-1.45 mg/g volatile suspended solids (VSS), in which the adsorption amount was 0.06-0.17 mg/g VSS and the degradation amount was 0.03-1.27 mg/g VSS. Tetracycline biosorption was dominant at its concentration of 1-3 mg/L, while biodegradation was predominant at 5-25 mg/L of tetracycline. At tetracycline concentration of 3-5 mg/L, the contribution of biosorption and biodegradation to tetracycline removal by algal-bacterial granular sludge process was almost equal. Algal-bacterial granular sludge could effectively degrade tetracycline through demethylation, dehydrogenation, deacylation, and deamination or their combination. In addition, the degradation products were nontoxic and hardly pose a threat to environmental health. The research results of this paper provide a solid theoretical basis for tetracycline removal by algal-bacterial granular sludge and a reference for the development of algal-bacterial granular sludge process for wastewater treatment in the presence of tetracycline. PRACTITIONER POINTS: Mature and stable algal-bacterial granular sludge was cultured. Tetracycline was removed by algal-bacterial granular sludge through biosorption and biodegradation. Algal-bacterial granular sludge could degrade tetracycline through demethylation, dehydrogenation, deacylation, and deamination or their combination. The degradation products were nontoxic.
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Affiliation(s)
- Shulian Wang
- School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan, China
- Innovation Demonstration Base of Ecological Environment Geotechnical and Ecological Restoration of Rivers and Lakes, Hubei University of Technology, Wuhan, China
| | - Yu Zhang
- School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan, China
| | - Hongmei Ge
- School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan, China
- Innovation Demonstration Base of Ecological Environment Geotechnical and Ecological Restoration of Rivers and Lakes, Hubei University of Technology, Wuhan, China
| | - Huan Hou
- School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan, China
| | - Huiqin Zhang
- School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan, China
- Innovation Demonstration Base of Ecological Environment Geotechnical and Ecological Restoration of Rivers and Lakes, Hubei University of Technology, Wuhan, China
| | - Kewu Pi
- School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan, China
- Innovation Demonstration Base of Ecological Environment Geotechnical and Ecological Restoration of Rivers and Lakes, Hubei University of Technology, Wuhan, China
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Trebuch LM, Schoofs K, Vaessen SMF, Neu TR, Janssen M, Wijffels RH, Vet LEM, Fernandes TV. N 2 -fixation can sustain wastewater treatment performance of photogranules under nitrogen-limiting conditions. Biotechnol Bioeng 2023; 120:1303-1315. [PMID: 36779371 DOI: 10.1002/bit.28349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 12/23/2022] [Accepted: 02/09/2023] [Indexed: 02/14/2023]
Abstract
Wastewater characteristics can vary significantly, and in some municipal wastewaters the N:P ratio is as low as 5 resulting in nitrogen-limiting conditions. In this study, the microbial community, function, and morphology of photogranules under nitrogen-replete (N+) and limiting (N-) conditions was assessed in sequencing batch reactors. Photogranules under N- condition were nitrogen deprived 2/3 of a batch cycle duration. Surprisingly, this nitrogen limitation had no adverse effect on biomass productivity. Moreover, phosphorus and chemical oxygen demand removal were similar to their removal under N+ conditions. Although performance was similar, the difference in granule morphology was obvious. While N+ photogranules were dense and structurally confined, N- photogranules showed loose structures with occasional voids. Microbial community analysis revealed high abundance of cyanobacteria capable of N2 -fixation. These were higher at N- (38%) than N+ (29%) treatments, showing that photogranules could adjust and maintain treatment performance and high biomass productivity by means of N2 -fixation.
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Affiliation(s)
- Lukas M Trebuch
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, The Netherlands.,Bioprocess Engineering, AlgaePARC Wageningen University, Wageningen, The Netherlands
| | - Kobe Schoofs
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, The Netherlands.,Bioprocess Engineering, AlgaePARC Wageningen University, Wageningen, The Netherlands
| | - Stijn M F Vaessen
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, The Netherlands.,Bioprocess Engineering, AlgaePARC Wageningen University, Wageningen, The Netherlands
| | - Thomas R Neu
- Microbiology of Interfaces, Department River Ecology, Helmholtz Centre for Environmental Research - UFZ, Magdeburg, Germany
| | - Marcel Janssen
- Bioprocess Engineering, AlgaePARC Wageningen University, Wageningen, The Netherlands
| | - René H Wijffels
- Bioprocess Engineering, AlgaePARC Wageningen University, Wageningen, The Netherlands.,Faculty of Biosciences and Aquaculture, Nord University, Bodø, Norway
| | - Louise E M Vet
- Department of Terrestrial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, The Netherlands
| | - Tânia V Fernandes
- Department of Aquatic Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, The Netherlands
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25
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Papadopoulos KP, Economou CN, Stefanidou N, Moustaka-Gouni M, Genitsaris S, Aggelis G, Tekerlekopoulou AG, Vayenas DV. A semi-continuous algal-bacterial wastewater treatment process coupled with bioethanol production. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 326:116717. [PMID: 36399810 DOI: 10.1016/j.jenvman.2022.116717] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 11/01/2022] [Accepted: 11/03/2022] [Indexed: 06/16/2023]
Abstract
Harnessing the biomass energy potential through biofuel production offers new outlets for a circular economy. In this study an integrated system which combine brewery wastewater treatment using algal-bacterial aggregates instead of activated sludge was developed. The use of algal-bacterial aggregates can eliminate the aeration requirements and significantly reduce the high biomass harvesting costs associated with algal monocultures. A sequencing batch reactor (SBR) setup operating with and without biomass recirculation was used to investigate pollutant removal rates, aggregation capacity and microbial community characteristics under a range of hydraulic retention times (HRTs) and solid retention times (SRTs). It was observed that biomass recirculation strategy significantly enhanced aggregation and pollutant removal (i.e., 78.7%, 94.2% and 75.2% for d-COD, TKN, and PO43--P, respectively). The microbial community established was highly diverse consisting of 161 Bacterial Operational Taxonomic Units (B-OTUs) and 16 unicellular Eukaryotic OTUs (E-OTUs). Escalation the optimal conditions (i.e., HRT = 4 d, SRT = 10 d) at pilot-scale resulted in nutrient starvation leading to 38-44% w/w carbohydrate accumulation. The harvested biomass was converted to bioethanol after acid hydrolysis followed by fermentation with Saccharomyces cerevisiae achieving a bioethanol production yield of 0.076 g bioethanol/g biomass. These data suggest that bioethanol production coupled with high-performance wastewater treatment using algal-bacterial aggregates is feasible, albeit less productive concerning bioethanol yields than systems exclusively designed for third and fourth-generation biofuel production.
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Affiliation(s)
| | - Christina N Economou
- Department of Chemical Engineering, University of Patras, Rio, GR-26504 Patras, Greece.
| | - Natassa Stefanidou
- School of Biology - Aristotle University of Thessaloniki, Thessaloniki, GR-54124, Greece
| | - Maria Moustaka-Gouni
- School of Biology - Aristotle University of Thessaloniki, Thessaloniki, GR-54124, Greece
| | - Savvas Genitsaris
- Section of Ecology and Taxonomy, School of Biology, National and Kapodistrian University of Athens, Zografou Campus, GR-15784 Athens, Greece
| | - George Aggelis
- Department of Biology, University of Patras, Rio, GR-26504 Patras, Greece
| | | | - Dimitris V Vayenas
- Department of Chemical Engineering, University of Patras, Rio, GR-26504 Patras, Greece; Institute of Chemical Engineering and High Temperature Chemical Processes (FORTH/ ICE-HT), Stadiou Str., Platani, GR-26504 Patras, Greece
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26
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Vincent F, Rao TS, Kumar R, Nancharaiah YV. Exploring the effects of organic loading rate and domestic wastewater treatment by algal-bacterial granules under natural daylight conditions. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2023; 95:e10831. [PMID: 36617440 DOI: 10.1002/wer.10831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 12/04/2022] [Accepted: 12/13/2022] [Indexed: 06/17/2023]
Abstract
Algal-bacterial granules or phototrophic granules (PGs) comprising phototrophic microorganisms and bacteria are explored in wastewater treatment for achieving both environmental and economic sustainability. This study describes development of PGs and their use in biological treatment of synthetic and real domestic wastewater (sewage) under natural daylight conditions and low organic loading rate (OLR). Development of PGs was sequentially recorded in a photobioreactor operated in photo-sequencing batch reactor (photo-SBR) mode at a low OLR of 1 kgCOD.m-3 .day-1 and the developed PGs was evaluated for treating synthetic wastewater and real municipal wastewater with 0.14 kg COD m-3 .day-1 . PGs formed in the photo-sequential batch reactor (SBR) were compact and dense and exhibited excellent settling properties. The removal efficiencies were determined to be up to 95%, 93%, 97%, 72%, and 88% for turbidity, COD, TOC, NH4 + -N, and NO2 - -N/NO3 - -N, respectively. Additionally, a reduction in total viable bacterial counts and fecal coliform bacteria up to 1.7 × 103 and 7.8 × 102 cfu.mL-1 , respectively, during treatment of real municipal wastewater was achieved. This study demonstrated cultivation of algal-bacterial granules or PGs and their application for treating real municipal wastewater under natural daylight and tropical climate conditions. Further studies are needed on understanding interactions among phototrophic, autotrophic, and heterotrophic microorganisms of complex algal-bacterial consortium for emerging applications in bioremediation and wastewater treatment. PRACTITIONER POINTS: Phototrophic granules (PGs) were cultivated from algal consortium and activated sludge inoculum in photo sequencing batch reactors. Granular photobioreactor was operated at low OLR of 1 kgCOD.m3 .day-1 for developing well-settling algal-bacterial granules. PGs were stable and showed efficient biological treatment of synthetic wastewater and real sewage. Removals for turbidity, pathogens, and ammonium were at 95%, 3-log, and 72%, respectively, from real sewage.
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Affiliation(s)
- Francis Vincent
- Biofouling and Biofilm Processes Section, WSCD, Chemistry Group, Bhabha Atomic Research Centre, Kalpakkam, India
| | - Toleti Subba Rao
- Biofouling and Biofilm Processes Section, WSCD, Chemistry Group, Bhabha Atomic Research Centre, Kalpakkam, India
| | - Rajesh Kumar
- Biofouling and Biofilm Processes Section, WSCD, Chemistry Group, Bhabha Atomic Research Centre, Kalpakkam, India
- Homi Bhabha National Institute, Mumbai, India
| | - Yarlagadda Venkata Nancharaiah
- Biofouling and Biofilm Processes Section, WSCD, Chemistry Group, Bhabha Atomic Research Centre, Kalpakkam, India
- Homi Bhabha National Institute, Mumbai, India
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27
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Advanced treatment of food processing effluent by indigenous microalgae-bacteria consortia: Population dynamics and enhanced nitrogen uptake. ALGAL RES 2022. [DOI: 10.1016/j.algal.2022.102913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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28
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Development of marine activated algae-bacterial granule: A novel replacement to the conventional algal remediation processes. ALGAL RES 2022. [DOI: 10.1016/j.algal.2022.102914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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Abbew AW, Amadu AA, Qiu S, Champagne P, Adebayo I, Anifowose PO, Ge S. Understanding the influence of free nitrous acid on microalgal-bacterial consortium in wastewater treatment: A critical review. BIORESOURCE TECHNOLOGY 2022; 363:127916. [PMID: 36087656 DOI: 10.1016/j.biortech.2022.127916] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 08/31/2022] [Accepted: 09/04/2022] [Indexed: 06/15/2023]
Abstract
Microalgal-bacterial consortium (MBC) constitutes a sustainable and efficient alternative to the conventional activated sludge process for wastewater treatment (WWT). Recently, integrating the MBC process with nitritation (i.e., shortcut MBC) has been proposed to achieve added benefits of reduced carbon and aeration requirements. In the shortcut MBC system, nitrite or free nitrous acid (FNA) accumulation exerts antimicrobial influences that disrupt the stable process performance. In this review, the formation and interactions that influence the performance of the MBC were firstly summarized. Then the influence of FNA on microalgal and bacterial monocultures and related mechanisms together with the knowledge gaps of FNA influence on the shortcut MBC were highlighted. Other challenges and future perspectives that impact the scale-up of the shortcut MBC for WWT were illustrated. A potential roadmap is proposed on how to maximize the stable operation of the shortcut MBC system for sustainable WWT and high-value biomass production.
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Affiliation(s)
- Abdul-Wahab Abbew
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Xiao Ling Wei 200, Nanjing 210094, Jiangsu, China
| | - Ayesha Algade Amadu
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Xiao Ling Wei 200, Nanjing 210094, Jiangsu, China
| | - Shuang Qiu
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Xiao Ling Wei 200, Nanjing 210094, Jiangsu, China
| | - Pascale Champagne
- Department of Chemistry, Queen's University, Kingston, Ontario K7L 3N6, Canada
| | - Ismaeel Adebayo
- School of Chemical Engineering, Nanjing University of Science and Technology, Xiao Ling Wei 200, Nanjing 210094, Jiangsu, China
| | - Peter Oluwaseun Anifowose
- School of Science, Nanjing University of Science and Technology, Xiao Ling Wei 200, Nanjing 210094, Jiangsu, China
| | - Shijian Ge
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Xiao Ling Wei 200, Nanjing 210094, Jiangsu, China.
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30
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Wang Q, Yang Y, Shen Q, Chen X, Li F, Wang J, Zhang Z, Lei Z, Yuan T, Shimizu K. Energy saving and rapid establishment of granular microalgae system from tiny microalgae cells: Effect of decrease in upflow air velocity under intermittent aeration condition. BIORESOURCE TECHNOLOGY 2022; 363:127860. [PMID: 36041681 DOI: 10.1016/j.biortech.2022.127860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 08/23/2022] [Accepted: 08/23/2022] [Indexed: 06/15/2023]
Abstract
The novel type of microalgae granules (MGs) derived from tiny microalgae cells has received extensive attention due to its great potential for nutrient remediation and resource recovery in wastewater treatment whereas the long start-up time with increased labor expenses remains a bottleneck. In this study, an operation strategy at reduced upflow air velocity (UAV = 0.49 cm/s in RA) under intermittent aeration mode was proposed and compared with RB at a higher UAV (0.98 cm/s) in terms of MGs formation, maintenance, and energy consumption. Although the formation of MGs in RA was delayed for 12 days compared to RB, 40.78 % increase in chlorophyll-a content was detected in MGs in RA along with more cost-effective carbon, nitrogen, and phosphorus removals due to efficient microalgae assimilation and energy reduction. Results from this study provide new insight into minimizing energy input for rapid establishment and stable operation of MG systems towards environmentally sustainable wastewater management.
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Affiliation(s)
- Qian Wang
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan; College of Environmental Science and Engineering, Ocean University of China, Qingdao 266003, China
| | - Yuyi Yang
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Qingyue Shen
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan; College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China
| | - Xingyu Chen
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Fengmin Li
- College of Environmental Science and Engineering, Ocean University of China, Qingdao 266003, China
| | - Jixiang Wang
- Graduate School 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
| | - Zhongfang Lei
- 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
| | - 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
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31
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Jiang Q, Chen H, Fu Z, Fu X, Wang J, Liang Y, Yin H, Yang J, Jiang J, Yang X, Wang H, Liu Z, Su R. Current Progress, Challenges and Perspectives in the Microalgal-Bacterial Aerobic Granular Sludge Process: A Review. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:13950. [PMID: 36360829 PMCID: PMC9655209 DOI: 10.3390/ijerph192113950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 10/18/2022] [Accepted: 10/25/2022] [Indexed: 06/16/2023]
Abstract
Traditional wastewater treatment technologies have become increasingly inefficient to meet the needs of low-consumption and sustainable wastewater treatment. Researchers are committed to seeking new wastewater treatment technologies, to reduce the pressure on the environment caused by resource shortages. Recently, a microalgal-bacterial granular sludge (MBGS) technology has attracted widespread attention due to its high efficiency wastewater treatment capacity, low energy consumption, low CO2 emissions, potentially high added values, and resource recovery capabilities. This review focused primarily on the following aspects of microalgal-bacterial granular sludge technology: (1) MBGS culture and maintenance operating parameters, (2) MBGS application in different wastewaters, (3) MBGS additional products: biofuels and bioproducts, (4) MBGS energy saving and consumption reduction: greenhouse gas emission reduction, and (5) challenges and prospects. The information in this review will help us better understand the current progress and future direction of the MBGS technology development. It is expected that this review will provide a sound theoretical basis for the practical applications of a MBGS technology in environmentally sustainable wastewater treatment, resource recovery, and system optimization.
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Affiliation(s)
- Qianrong Jiang
- Ecological Environment Management and Assessment Center, Central South University of Forestry and Technology, Changsha 410004, China
- School of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
- South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou 510655, China
| | - Honglei Chen
- Ecological Environment Management and Assessment Center, Central South University of Forestry and Technology, Changsha 410004, China
- School of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - Zeding Fu
- School of Hydraulic and Environmental Engineering, Changsha University of Science & Technology, Changsha 410114, China
| | - Xiaohua Fu
- Ecological Environment Management and Assessment Center, Central South University of Forestry and Technology, Changsha 410004, China
- School of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - Jiacheng Wang
- Ecological Environment Management and Assessment Center, Central South University of Forestry and Technology, Changsha 410004, China
- School of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - Yingqi Liang
- Ecological Environment Management and Assessment Center, Central South University of Forestry and Technology, Changsha 410004, China
- School of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - Hailong Yin
- Ecological Environment Management and Assessment Center, Central South University of Forestry and Technology, Changsha 410004, China
- School of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - Junbo Yang
- Ecological Environment Management and Assessment Center, Central South University of Forestry and Technology, Changsha 410004, China
- School of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - Jie Jiang
- Ecological Environment Management and Assessment Center, Central South University of Forestry and Technology, Changsha 410004, China
- School of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
- South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou 510655, China
| | - Xinxin Yang
- Ecological Environment Management and Assessment Center, Central South University of Forestry and Technology, Changsha 410004, China
- School of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - He Wang
- Ecological Environment Management and Assessment Center, Central South University of Forestry and Technology, Changsha 410004, China
- School of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
| | - Zhiming Liu
- Department of Biology, Eastern New Mexico University, Portales, NM 88130, USA
| | - Rongkui Su
- Ecological Environment Management and Assessment Center, Central South University of Forestry and Technology, Changsha 410004, China
- School of Environmental Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, China
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Gikonyo JG, Ansari A, Park C, Tobiason J. Physical characterization of oxygenic photogranules. Biochem Eng J 2022. [DOI: 10.1016/j.bej.2022.108592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Ji B, Fan S, Liu Y. A continuous-flow non-aerated microalgal-bacterial granular sludge process for aquaculture wastewater treatment under natural day-night conditions. BIORESOURCE TECHNOLOGY 2022; 350:126914. [PMID: 35231593 DOI: 10.1016/j.biortech.2022.126914] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 02/20/2022] [Accepted: 02/23/2022] [Indexed: 06/14/2023]
Abstract
This study developed a continuous-flow non-aerated microalgal-bacterial granular tubular reactor for aquaculture wastewater treatment under natural day-night conditions. Results showed that daytime was favorable for ammonia removal while nighttime for nitrate removal. Over 99% of nitrite-N could be removed over the day-night cycles at a hydraulic retention time of 6 h. However, the phosphorus removal was found to be sensitive to the weather condition, ranging from 35.0% to 96.6%. It was also observed that dissolved oxygen produced by microalgae in daytime was sufficient for creating a 6-h aerobic condition in nighttime for sustaining heterotrophic activity. Chlorella and Leptolyngbya were identified as the most abundant algae related to weather changes. Metagenomics analysis revealed that the high nitrite removal relied mainly on nitrite reduction. These experimental findings offer new insights into the non-aerated microalgal-bacterial granular sludge for environmentally sustainable aquaculture wastewater treatment.
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Affiliation(s)
- Bin Ji
- Department of Water and Wastewater Engineering, Wuhan University of Science and Technology, Wuhan 430065, PR China.
| | - Siqi Fan
- Department of Water and Wastewater Engineering, Wuhan University of Science and Technology, Wuhan 430065, PR China
| | - Yu Liu
- Advanced Environmental Biotechnology Centre, Nanyang Environment & Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore 637141, Singapore; School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
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35
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Kuizu S, Ruiyu W, Hui Z, Wei W, Tianwei H. Mechanism and regulation of filamentous algal-bacterial symbiosis based on microbiological quorum sensing. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2022; 94:e10697. [PMID: 35243720 DOI: 10.1002/wer.10697] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Revised: 01/15/2022] [Accepted: 02/07/2022] [Indexed: 06/14/2023]
Abstract
In algae-bacteria symbiotic systems, algae and bacteria work cooperatively to reduce aeration demand and carbon emissions during wastewater treatment. However, controlling and stabilizing microbial communities in the conventional algae-bacteria symbiotic systems are complicated and unstable. We, therefore, developed a novel sewage treatment system based on a filamentous algae-bacterial symbiotic granule system (AB) in a photo-sequencing batch reactor (PSBR). The exogenous signal molecules (i.e., N-acyl-homoserine lactones [AHLs]) were applied to promote the algae-bacteria consortia formation. The characteristics and performance of the mature algae-bacterial granular consortia were investigated and then compared with that of the activated sludge (AS) system under identical operating conditions. The chemical oxidation demand (COD) removal efficiencies were greater than 90% in the dynamic synergistic investigation, even without aeration. However, the addition of AHLs (5, 50, and 200 nmol/L) had a negligible effect on treatment performance. In static conditions, 10-9 nmol/L of AHLs can significantly regulate the algae-bacteria symbiotic system, and AHLs (<50 nmol/L) improved COD and NH4 + removal efficiencies by up to 90%. Moreover, the addition of AHLs augmented polysaccharide secretion but had little effect on protein secretion. In comparison to the AS system, the AB system demonstrated promise in terms of pollution removal efficiency and microbial diversity enhancement. PRACTITIONER POINTS: Oscillatoria can serve as an excellent biological carrier for immobilizing bacteria. AHLs (10-9 mol/L) regulated the operation state of algae-bacteria symbiotic system. AHLs altered the composition and content of EPS in the algae-bacteria system.
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Affiliation(s)
- Su Kuizu
- Department of Civil Engineering, Hefei University of Technology, Hefei, China
- Anhui Provincial Engineering Laboratory for Rural Water Environment and Resources, Hefei, China
| | - Wu Ruiyu
- Department of Civil Engineering, Hefei University of Technology, Hefei, China
- China Energy Engineering Group Anhui Electric Power Desigh Institute Co., Ltd., Hefei, China
| | - Zhou Hui
- Department of Civil Engineering, Hefei University of Technology, Hefei, China
- Anhui Provincial Architectural Design and Research Institute Co., Ltd., Hefei, China
| | - Wang Wei
- Department of Civil Engineering, Hefei University of Technology, Hefei, China
- Anhui Provincial Engineering Laboratory for Rural Water Environment and Resources, Hefei, China
| | - Hao Tianwei
- Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau, China
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36
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Ji B. Towards environment-sustainable wastewater treatment and reclamation by the non-aerated microalgal-bacterial granular sludge process: Recent advances and future directions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 806:150707. [PMID: 34599950 DOI: 10.1016/j.scitotenv.2021.150707] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 09/23/2021] [Accepted: 09/27/2021] [Indexed: 06/13/2023]
Abstract
Currently, we are increasingly aware of the environmental unsustainability of the conventional wastewater treatment processes, e.g. extensive energy consumption and greenhouse gases emission. As such, the light-motivated non-aerated microalgal-bacterial granular sludge (MBGS) process has drawn extensive attention recently. This review aims to offer the important recent advances and future directions on the emerging non-aerated MBGS process for wastewater treatment and reclamation. The formation mechanism of MBGS from activated sludge is revealed to be the mobility under environmental stress such as shear force and nutrient deficiency. The key environmental factors affecting the non-aerated MBGS process are analyzed in terms with light, temperature, stirring and influent composition. Furthermore, sceneries of future outdoor processes by non-aerated MBGS are outlined. In turns out that the non-aerated MBGS offers a harmonious ecosystem to enrich the pollutants from wastewater to biomass, which can be potentially utilized as biofertilizer and feed for plant and animal, respectively. This review is expected to deepen our insights into the emerging non-aerated MBGS process for environment-sustainable wastewater treatment and reclamation.
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Affiliation(s)
- Bin Ji
- Department of Water and Wastewater Engineering, Wuhan University of Science and Technology, Wuhan 430065, China.
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37
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Ji B, Liu C. CO 2 improves the microalgal-bacterial granular sludge towards carbon-negative wastewater treatment. WATER RESEARCH 2022; 208:117865. [PMID: 34826738 DOI: 10.1016/j.watres.2021.117865] [Citation(s) in RCA: 41] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 11/08/2021] [Accepted: 11/09/2021] [Indexed: 06/13/2023]
Abstract
As a promising wastewater treatment technology, little is known about whether the greenhouse gas CO2 can be applied for microalgal-bacterial granular sludge (MBGS) process. This article applied CO2 for improving MBGS process. It was found that the physical structure of MBGS with no CO2 addition appeared to have a trend to be loose and disintegrated, with a sludge volume index at 5 min (SVI5) of over 150 mL/g and an average pore size of 35 nm in 60 d operation. However, CO2 could maintain the compact and integrated structure of MBGS with a SVI5 lower than 50 mL/g and an average pore size ranging from 10 to 13 nm. CO2 could enhance the production of extracellular polysaccharides and aromatic protein, thus favoring the granular stability of MBGS. CO2 could change the aqueous environment, e.g. lowering the pH values, which resulted in different microbial communities as well as metabolic potentials of MBGS. As for the reactor performance, CO2 could significantly improve the removals of organics and phosphorus, evidenced by the enhancement of genes encoding acetate-CoA ligase and ATPase, respectively. Although the mass ratio of algae to bacteria was elevated by CO2 addition, the ammonia removal related enzymes of glutamate dehydrogenase and glutamine synthetase could be negatively and positively impacted by CO2, respectively. Mass balance analysis of carbon indicated that CO2 could provide additional carbon source as well as enhance the buffering capacity for the MBGS system. Further estimations suggested that the MBGS process could achieve a carbon-negative objective for municipal wastewater treatment by supplying CO2 as additional carbon source. Hence, CO2 supply for MBGS process in municipal wastewater treatment can be deemed as a two-birds-one-stone strategy, i.e. maintaining the granular stability and eliminating the carbon emission. This article can advance our basic knowledge on MBGS process towards environment-sustainable wastewater treatment.
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Affiliation(s)
- Bin Ji
- Department of Water and Wastewater Engineering, Wuhan University of Science and Technology, Wuhan, 430065, China.
| | - Cheng Liu
- Department of Water and Wastewater Engineering, Wuhan University of Science and Technology, Wuhan, 430065, China
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38
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Assuaging Microalgal Harvesting Woes via Attached Growth: A Critical Review to Produce Sustainable Microalgal Feedstock. SUSTAINABILITY 2021. [DOI: 10.3390/su132011159] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Third-generation biofuels that are derived from microalgal biomass have gained momentum as a way forward in the sustainable production of biodiesel. Such efforts are propelled by the intention to reduce our dependence on fossil fuels as the primary source of energy. Accordingly, growing microalgal biomass in the form of suspended cultivation has been a conventional technique for the past few decades. To overcome the inevitable harvesting shortcomings arising from the excessive energy and time needed to separate the planktonic microalgal cells from water medium, researchers have started to explore attached microalgal cultivation systems. This cultivation mode permits the ease of harvesting mature microalgal biomass, circumventing the need to employ complex harvesting techniques to single out the cells, and is economically attractive. However, the main bottleneck associated with attached microalgal growth is low biomass production due to the difficulties the microalgal cells have in forming attachment and populating thereafter. In this regard, the current review encompasses the novel techniques adopted to promote attached microalgal growth. The physicochemical effects such as the pH of the culture medium, hydrophobicity, as well as the substratum surface properties and abiotic factors that can determine the fate of exponential growth of attached microalgal cells, are critically reviewed. This review aims to unveil the benefits of an attached microalgal cultivation system as a promising harvesting technique to produce sustainable biodiesel for lasting applications.
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39
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Park C, Takeuchi N. Unmasking photogranulation in decreasing glacial albedo and net autotrophic wastewater treatment. Environ Microbiol 2021; 23:6391-6404. [PMID: 34545673 PMCID: PMC9292683 DOI: 10.1111/1462-2920.15780] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 09/13/2021] [Accepted: 09/16/2021] [Indexed: 11/29/2022]
Abstract
In both natural and built environments, microbes on occasions manifest in spherical aggregates instead of substratum‐affixed biofilms. These microbial aggregates are conventionally referred to as granules. Cryoconites are mineral rich granules that appear on glacier surfaces and are linked with expanding surface darkening, thus decreasing albedo, and enhanced melt. The oxygenic photogranules (OPGs) are organic rich granules that grow in wastewater, which enables wastewater treatment with photosynthetically produced oxygen and which presents potential for net autotrophic wastewater treatment in a compact system. Despite obvious differences inherent in the two, cryoconite and OPG pose striking resemblance. In both, the order Oscillatoriales in Cyanobacteria envelope inner materials and develop dense spheroidal aggregates. We explore the mechanism of photogranulation on account of high similarity between cryoconites and OPGs. We contend that there is no universal external cause for photogranulation. However, cryoconites and OPGs, as well as their intravariations, which are all under different stress fields, are the outcome of universal physiological processes of the Oscillatoriales interfacing with goldilocks interactions of stresses. Finding the rules of photogranulation may enhance engineering of glacier and wastewater systems to manipulate their ecosystem impacts.
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Affiliation(s)
- Chul Park
- Department of Civil and Environmental Engineering, University of Massachusetts Amherst, Amherst, Massachusetts, 01003, USA
| | - Nozomu Takeuchi
- Department of Earth Sciences, Graduate School of Science, Chiba University, Chiba, 263-8522, Japan
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40
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Ansari AA, Ansari AA, Abouhend AS, Gikonyo JG, Park C. Photogranulation in a Hydrostatic Environment Occurs with Limitation of Iron. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:10672-10683. [PMID: 34255495 DOI: 10.1021/acs.est.0c07374] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Filamentous cyanobacteria are an essential element of oxygenic photogranules for granule-based wastewater treatment with photosynthetic aeration. Currently, mechanisms for the selection of this microbial group and their development in the granular structure are not well understood. Here, we studied the characteristics and fate of iron in photogranulation that proceeds in a hydrostatic environment with an activated sludge (AS) inoculum. We found that the level of Fe in bulk liquids (FeBL) sharply increased due to the decay of the inoculum but quickly diminished along with the bloom of microalgae and the advent of the oxic environment. Iron linked with extracellular polymeric substances (FeEPS) continued to decline but reached steady low values, which occurred along with the appearance of granular structure. Strong negative correlations were found between FeEPS and the pigments specific for cyanobacteria. Spectroscopies revealed the presence of amorphous ferric oxides in pellet biomass, which seemed to remain unaltered during the photogranulation process. These results suggest that the availability of FeEPS in AS inoculums-after algal bloom-selects cyanobacteria, and the limitation of this Fe pool becomes an important driver for cyanobacteria to granulate in a hydrostatic environment. We therefore propose that the availability of iron has a strong influence on the photogranulation process.
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Affiliation(s)
- Abeera A Ansari
- Department of Civil and Environmental Engineering, University of Massachusetts, Amherst, Amherst, Massachusetts 01003, United States
- U.S.-Pakistan Center for Advanced Studies in Energy (USPCAS-E), National University of Sciences and Technology (NUST), H-12 Sector, 44000 Islamabad , Pakistan
| | - Arfa A Ansari
- Department of Civil and Environmental Engineering, University of Massachusetts, Amherst, Amherst, Massachusetts 01003, United States
| | - Ahmed S Abouhend
- Department of Civil and Environmental Engineering, University of Massachusetts, Amherst, Amherst, Massachusetts 01003, United States
| | - Joseph G Gikonyo
- Department of Civil and Environmental Engineering, University of Massachusetts, Amherst, Amherst, Massachusetts 01003, United States
| | - Chul Park
- Department of Civil and Environmental Engineering, University of Massachusetts, Amherst, Amherst, Massachusetts 01003, United States
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41
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Safitri AS, Hamelin J, Kommedal R, Milferstedt K. Engineered methanotrophic syntrophy in photogranule communities removes dissolved methane. WATER RESEARCH X 2021; 12:100106. [PMID: 34195589 PMCID: PMC8237362 DOI: 10.1016/j.wroa.2021.100106] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/01/2021] [Revised: 06/03/2021] [Accepted: 06/05/2021] [Indexed: 06/13/2023]
Abstract
The anaerobic treatment of wastewater leads to the loss of dissolved methane in the effluent of the treatment plant, especially when operated at low temperatures. The emission of this greenhouse gas may reduce or even offset the environmental gain from energy recovery through anaerobic treatment. We demonstrate here the removal and elimination of these comparably small methane concentrations using an ecologically engineered methanotrophic community harbored in oxygenic photogranules. We constructed a syntrophy between methanotrophs enriched from activated sludge and cyanobacteria residing in photogranules and maintained it over a two-month period in a continuously operated reactor. The novel community removed dissolved methane during stable reactor operation by on average 84.8±7.4% (±standard deviation) with an average effluent concentration of dissolved methane of 4.9±3.7 mg CH4∙l-1. The average methane removal rate was 26 mg CH4∙l-1∙d-1, with an observed combined biomass yield of 2.4 g VSS∙g CH4 -1. The overall COD balance closed at around 91%. Small photogranules removed methane more efficiently than larger photogranule, likely because of a more favorable surface to volume ratio of the biomass. MiSeq amplicon sequencing of 16S and 23S rRNA revealed a potential syntrophic chain between methanotrophs, non-methanotrophic methylotrophs and filamentous cyanobacteria. The community composition between individual photogranules varied considerably, suggesting cross-feeding between photogranules of different community composition. Methanotrophic photogranules may be a viable option for dissolved methane removal as anaerobic effluent post-treatment.
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Affiliation(s)
- Anissa Sukma Safitri
- Department of Chemistry, Bioscience and Environmental Engineering, University of Stavanger, 4036 Stavanger, Norway
| | - Jérôme Hamelin
- INRAE, Univ Montpellier, LBE, 102 Avenue des Etangs, 11100, Narbonne, France
| | - Roald Kommedal
- Department of Chemistry, Bioscience and Environmental Engineering, University of Stavanger, 4036 Stavanger, Norway
| | - Kim Milferstedt
- INRAE, Univ Montpellier, LBE, 102 Avenue des Etangs, 11100, Narbonne, France
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42
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Dey I, Banerjee S, Bose R, Pal R. Spatiotemporal variations in the composition of algal mats in wastewater treatment ponds of tannery industry. ENVIRONMENTAL MONITORING AND ASSESSMENT 2021; 193:359. [PMID: 34037860 DOI: 10.1007/s10661-021-09144-5] [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: 08/19/2020] [Accepted: 05/17/2021] [Indexed: 06/12/2023]
Abstract
Wastewater Treatment Pond (WTP) is an effective remediation technology for economically developing nations. Although it's excessive organic and nutrient loads with higher water logging time triggers mixed and unprofitable microalgal mats. This may serve as a seeding source for Cyanobacterial bloom in receiving waterbodies. Since, to maintain the growth of desirable algal species in WTPs, understanding towards environmental regulation and algal mat composition is important, especially for tropical countries, like India. In this study, biological treatment pond (BTP) and outlet pond (OP), of a tannery effluent treatment plant in eastern coast of India, were chosen for surveying the algal community composition concerning ecological parameters. Nearly, both the ponds were polluted, but the diversity was lower in BTP due to its elevated nutrient content (Ammonia 173 mg L-1) and higher persistent organic matters (COD 301.7 mg L-1) than OP. Using canonical correspondence analysis, seasonal variations showed higher species abundance during early summer compared to other seasons. A total of 37 taxa forming thick algal mats were recorded. The matrix of mats was mainly composed of Cyanobacterial members such as Phormidium, Leptolyngbya, Spirulina, and Pseudanabaena, followed by diatoms, especially Amphora and Nitzschia. Diatoms commonly occurred as embedded component in the entangled matrix of blue-green algal filaments. Hierarchical cluster analysis was employed to group all these taxa based on their seasonal appearance and abundance. This year-long intensive study revealing seasonal algal mat composition patterns in these WTPs will ultimately safeguard the livelihood and security of adjoining localities through proper site-specific pollution control.
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Affiliation(s)
- Iman Dey
- Phycology Laboratory, Department of Botany, University of Calcutta, 35 Ballygunge Circular Road, Kolkata, 700019, West Bengal, India
| | - Sreemanti Banerjee
- Phycology Laboratory, Department of Botany, University of Calcutta, 35 Ballygunge Circular Road, Kolkata, 700019, West Bengal, India
| | - Rahul Bose
- Phycology Laboratory, Department of Botany, University of Calcutta, 35 Ballygunge Circular Road, Kolkata, 700019, West Bengal, India
| | - Ruma Pal
- Phycology Laboratory, Department of Botany, University of Calcutta, 35 Ballygunge Circular Road, Kolkata, 700019, West Bengal, India.
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43
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Segawa T, Takeuchi N, Mori H, Rathnayake RMLD, Li Z, Akiyoshi A, Satoh H, Ishii S. Redox stratification within cryoconite granules influences the nitrogen cycle on glaciers. FEMS Microbiol Ecol 2021; 96:5912832. [PMID: 32990745 DOI: 10.1093/femsec/fiaa199] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 09/25/2020] [Indexed: 11/12/2022] Open
Abstract
Cryoconite granules are naturally occurring microbial structures on glacier surfaces worldwide. They play a key role in carbon and nitrogen cycling in glacier ecosystems and can accelerate the melting of snow and ice. However, detailed mechanism of nitrogen cycling in cryoconite granules remains unclear. Here, we demonstrate that redox stratification affects the spatial distribution of N cycling processes in cryoconite granules. Based on microsensor measurements for O2, NH4+, NO2- and NO3-, we identified the presence of fine-scale redox stratification within cryoconite granules. Cyanobacteria at the surface layer of the granules created oxic conditions, whereas the inner core of the granules was anoxic. Metatranscriptomic analyses indicated the active occurrences of nitrification in the inner core, whereas denitrification actively occurred both in the inner core and the surface layer of the granules. Cyanobacteria in the inner core of the granules were inactive, and likely dead and being degraded, providing carbon and nitrogen to support nitrifiers and denitrifiers. Quantities of nitrification genes/transcripts were greater in large cryoconite granules than small ones, most likely because nitrogen substrates were more abundantly present in the inner core of large granules due to distinct redox stratification. Our results suggest that the development of a granular structure of cryoconite granules can largely affect carbon and nitrogen cycling on glaciers.
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Affiliation(s)
- Takahiro Segawa
- Center for Life Science Research, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi 409-3898, Japan
| | - Nozomu Takeuchi
- Department of Earth Sciences, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan
| | - Hiroshi Mori
- Department of Informatics, National Institute of Genetics, 1111 Yata, Mishima, Shizuoka 411-8540, Japan
| | - Rathnayake M L D Rathnayake
- Division of Environmental Engineering, Faculty of Engineering, Hokkaido University, North-13, West-8, Sapporo 060-8628, Japan
| | - Zhongqin Li
- Laboratory of Cryospheric Sciences, Northwest Institute of Eco-Environment and National Resources/Tianshan Glaciological Station, Chinese Academy of Sciences, Lanzhou 730000, Gansu, China
| | - Ayumi Akiyoshi
- National Institute of Polar Research, 10-3 Midori-cho, Tachikawa, Tokyo 190-8518, Japan
| | - Hisashi Satoh
- Division of Environmental Engineering, Faculty of Engineering, Hokkaido University, North-13, West-8, Sapporo 060-8628, Japan
| | - Satoshi Ishii
- Department of Soil, Water and Climate, University of Minnesota, St Paul, MN 55108, USA.,BioTechnology Institute, University of Minnesota, St Paul, MN 55108, USA
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44
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Ji B, Wang S, Silva MRU, Zhang M, Liu Y. Microalgal-bacterial granular sludge for municipal wastewater treatment under simulated natural diel cycles: Performances-metabolic pathways-microbial community nexus. ALGAL RES 2021. [DOI: 10.1016/j.algal.2021.102198] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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45
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Ji B, Zhu L, Wang S, Liu Y. Temperature-effect on the performance of non-aerated microalgal-bacterial granular sludge process in municipal wastewater treatment. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 282:111955. [PMID: 33453624 DOI: 10.1016/j.jenvman.2021.111955] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 11/11/2020] [Accepted: 01/03/2021] [Indexed: 06/12/2023]
Abstract
This paper investigated the performance of non-aerated microalgal-bacterial granular sludge (MBGS) process in municipal wastewater treatment at different temperatures. Results showed that the 70.5%, 81.9% and 86.1% of chemical oxygen demand (COD) could be removed at 15, 22 and 30 °C, respectively, indicating that a high temperature favored removal of organics due to promoted biomass growth. It was found that most of ammonia-N was removed via microbial assimilation by microalgae and bacteria in granules, with bacterial assimilation being dominant at the lower temperature. The phosphorus removal efficiency of 90.1% was achieved at 22 °C, with the presence of abundant Leptolyngbyales, a potential phosphorus accumulating alga. Chlorophyta grew much faster than Leptolyngbyales at 30 °C in microalgal-bacterial granules. It can be concluded that the contributions of microalgal and bacterial assimilations toward COD, ammonia and P removal appeared to be temperature-dependent, i.e. temperature could alter the symbiotic relationship between microalgae and bacteria. This study would contribute to the application of non-aerated MBGS process in municipal wastewater treatment with seasonal variation of temperature.
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Affiliation(s)
- Bin Ji
- Department of Water and Wastewater Engineering, Wuhan University of Science and Technology, Wuhan, 430065, China.
| | - Lin Zhu
- Department of Water and Wastewater Engineering, Wuhan University of Science and Technology, Wuhan, 430065, China
| | - Shulian Wang
- Hubei Key Laboratory of Ecological Remediation for Rivers-Lakes and Algal Utilization, Hubei University of Technology, Wuhan, 430068, China; Advanced Environmental Biotechnology Centre, Nanyang Environment & Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore, 637141, Singapore
| | - Yu Liu
- Advanced Environmental Biotechnology Centre, Nanyang Environment & Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore, 637141, Singapore; School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore
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46
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Brockmann D, Gérand Y, Park C, Milferstedt K, Hélias A, Hamelin J. Wastewater treatment using oxygenic photogranule-based process has lower environmental impact than conventional activated sludge process. BIORESOURCE TECHNOLOGY 2021; 319:124204. [PMID: 33038652 DOI: 10.1016/j.biortech.2020.124204] [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: 07/27/2020] [Revised: 09/21/2020] [Accepted: 09/27/2020] [Indexed: 05/21/2023]
Abstract
The Life Cycle Assessment (LCA) methodology was applied to assess the environmental feasibility of a novel wastewater treatment technology based on oxygenic photogranules (OPG) biomass in comparison to a conventional activated sludge (CAS) system. LCA using laboratory scale experimental data allowed for eco-design of the process during the early stage of process development at laboratory scale. Electricity consumption related to artificial lighting, the fate of the generated biomass (renewable energy and replacement of mineral fertilizer), and the nitrogen flows in the OPG system were identified as major contributors to the potential environmental impact of the OPG treatment system. These factors require optimization in order to reduce the environmental impact of the overall OPG system. Nonetheless, the environmental impact of a non-optimized OPG scenario was generally lower than for a CAS reference system. With an optimization of the artificial lighting system, an energy neutral treatment system may be within reach.
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Affiliation(s)
- Doris Brockmann
- INRAE, Univ Montpellier, Bio2E, 102 avenue des Etangs, 11100 Narbonne, France; ELSA Research Group, Montpellier, France.
| | - Yves Gérand
- ELSA Research Group, Montpellier, France; INRAE, Univ Montpellier, LBE, Narbonne, France
| | - Chul Park
- Department of Civil and Environmental Engineering, University of Massachusetts, Amherst, MA 01003, USA
| | | | - Arnaud Hélias
- ELSA Research Group, Montpellier, France; INRAE, Univ Montpellier, LBE, Montpellier SupAgro, Montpellier, France
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47
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Xu Z, Wang H, Cheng P, Chang T, Chen P, Zhou C, Ruan R. Development of integrated culture systems and harvesting methods for improved algal biomass productivity and wastewater resource recovery - A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 746:141039. [PMID: 32750578 DOI: 10.1016/j.scitotenv.2020.141039] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 07/15/2020] [Accepted: 07/15/2020] [Indexed: 06/11/2023]
Abstract
Microalgae biomass has been considered as a potential feedstock for the production of renewable chemicals and biofuels. Microalgae culture combined with wastewater treatment is a promising approach to improve the sustainability of the business model. However, algae culture and harvest account for the majority of the high costs, hindering the development of the microalgae-based wastewater utilization. Cost-effective culture systems and harvesting methods for enhancing biomass yield and reducing the cost of resource recovery have become extremely urgent and important. In this review, different commonly used culture systems for microalgae are discussed; the current harvesting methods with different culture systems have also been evaluated. Also, the inherent characteristics of inefficiency in algae wastewater treatment are elaborated. Current literature collectively supports that a biofilm type device is a system designed for higher biomass productivity, and offers ease of harvesting, in small-scale algae cultivation. Additionally, bio-flocculation, which uses one kind of flocculated microalgae to concentrate on another kind of non-flocculated microalgae is a low-cost and energy-saving alternative harvesting method. These findings provide insight into a comprehensive understanding of integrated culture systems and harvesting methods for microalgae-based wastewater treatment.
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Affiliation(s)
- Zhihui Xu
- School of Marine Sciences, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Haixia Wang
- College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Pengfei Cheng
- College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo, Zhejiang 315211, China; Center for Biorefining and Department of Bioproducts and Biosystems Engineering, University of Minnesota-Twin Cities, Saint Paul, MN 55108, USA.
| | - Ting Chang
- College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Paul Chen
- Center for Biorefining and Department of Bioproducts and Biosystems Engineering, University of Minnesota-Twin Cities, Saint Paul, MN 55108, USA
| | - Chengxu Zhou
- College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo, Zhejiang 315211, China
| | - Roger Ruan
- Center for Biorefining and Department of Bioproducts and Biosystems Engineering, University of Minnesota-Twin Cities, Saint Paul, MN 55108, USA
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48
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Ouazaite H, Milferstedt K, Hamelin J, Desmond-Le Quéméner E. Mapping the biological activities of filamentous oxygenic photogranules. Biotechnol Bioeng 2020; 118:601-611. [PMID: 33006374 DOI: 10.1002/bit.27585] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 09/17/2020] [Accepted: 09/28/2020] [Indexed: 11/08/2022]
Abstract
Oxygenic photogranules have been suggested as alternatives to activated sludge in wastewater treatment. Challenging for modeling photogranule-based processes is the heterogeneity of photogranule morphologies, resulting in different activities by photogranule type. The measurement of microscale-activities of filamentous photogranules is particularly difficult because of their labile interfaces. We present here an experimental and modeling approach to quantify phototrophic O2 production, heterotrophic O2 consumption, and O2 diffusion in filamentous photogranules. We used planar optodes for the acquisition of spatio-temporal oxygen distributions combined with two-dimensional mathematical modeling. Light penetration into the photogranule was the factor controlling photogranule activities. The spatial distribution of heterotrophs and phototrophs had less impact. The photosynthetic response of filaments to light was detectable within seconds, emphasizing the need to analyze dynamics of light exposure of individual photogranules in photobioreactors. Studying other recurring photogranule morphologies will eventually enable the description of photogranule-based processes as the interplay of interacting photogranule populations.
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49
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Joosten ED, Hamelin J, Milferstedt K. Simple Time-lapse Imaging for Quantifying the Hydrostatic Production of Oxygenic Photogranules. Bio Protoc 2020; 10:e3784. [PMID: 33659439 DOI: 10.21769/bioprotoc.3784] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 07/29/2020] [Accepted: 08/21/2020] [Indexed: 11/02/2022] Open
Abstract
Oxygenic photogranules (OPGs) are dense, three-dimensional aggregates containing a syntrophic, light-driven microbial community. Their temporal and spatial development interests microbial ecologists working at the bioprocess engineering interface, as this knowledge can be used to optimize biotechnological applications, such as wastewater treatment and biomass valorization. The method presented here enables the high-throughput quantification of photogranulation. OPGs are produced from a loose sludge-like microbial matrix in hydrostatic batch cultures exposed to light. This matrix transforms into a consolidated, roughly spherical aggregate over time. Photogranulation is quantified by time-lapse imaging coupled to automated image analysis. This allows studying the development of many OPGs simultaneously and in a fully automated way to systematically test what factors drive photogranulation. The protocol can also be used to quantify other types of (a)biotic aggregation.
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Affiliation(s)
- Esmee D Joosten
- INRAE, Univ Montpellier, LBE, 102 Avenue des Etangs, 11100, Narbonne, France
| | - Jérôme Hamelin
- INRAE, Univ Montpellier, LBE, 102 Avenue des Etangs, 11100, Narbonne, France
| | - Kim Milferstedt
- INRAE, Univ Montpellier, LBE, 102 Avenue des Etangs, 11100, Narbonne, France
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Kwon G, Le LT, Jeon J, Noh J, Jang Y, Kang D, Jahng D. Effects of light and mass ratio of microalgae and nitrifiers on the rates of ammonia oxidation and nitrate production. Biochem Eng J 2020. [DOI: 10.1016/j.bej.2020.107656] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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