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Franco Vieira B, Ramos-Muñoz VM, Zahedi S, Abreu B Silva Rabelo C, Zaiat M, G Fermoso F, González-Arias J. Unlocking the anaerobic conversion of crop residues: Biological pretreatments and the role of sulfide pathway in lignin degradation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2025; 967:178739. [PMID: 39946880 DOI: 10.1016/j.scitotenv.2025.178739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2024] [Revised: 01/12/2025] [Accepted: 02/03/2025] [Indexed: 03/05/2025]
Abstract
Research on the reutilization of crop residues has gained significant attention as a strategy for generating energy and high-value chemicals from renewable sources, while simultaneously reducing feedstock costs and mitigating environmental pollution. Crop residues have been effectively applied in lignocellulosic sulfate-reducing bioreactors (LSRBs) for the treatment of mining-influenced water. A comprehensive evaluation of the state-of-the-art in LSRBs reveals their potential for leveraging syntrophic aerobic-anaerobic interactions between sulfate-reducing bacteria and facultative species, alongside cellulolytic-fermentative microorganisms, to facilitate the pretreatment of lignocellulosic biomass for biorefinery applications. Key variables influencing the availability of enzymatic substrates and the activity of lignin-degrading enzymes are identified, along with strategies to enhance catalytic efficiency. Additionally, approaches to ensure the availability of trace elements and to control the production of toxic intermediates that may hinder treatment processes are elucidated. Prominent strategies include the application of microaeration and the use of co-substrates. An innovative aspect is the exploitation of metal sulfide precipitation to mitigate toxicity while preventing the sequestration of hydrogen peroxide - an essential substrate for enzymatic activity - by sulfides generated during the process. This review emphasizes the need for scientific advancements focused on optimizing the valorization of lignocellulosic residues. A particular focus is placed on advancing the understanding of lignin's anaerobic degradation mechanisms, especially in systems co-treating lignocellulosic waste and mining-influenced waters. Such advancements hold promise for enhancing the efficiency and sustainability of biorefinery operations.
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Affiliation(s)
- Bárbara Franco Vieira
- Instituto de la Grasa, Spanish National Research Council (CSIC), Campus Universitario Pablo de Olavide, Ed. 46, Ctra. de Utrera, km. 1, Seville 41013, Spain; Biological Processes Laboratory, São Carlos School of Engineering, University of São Paulo, 1100 João Dagnone Avenue, 13563-120 São Carlos, SP, Brazil
| | - Víctor M Ramos-Muñoz
- Instituto de la Grasa, Spanish National Research Council (CSIC), Campus Universitario Pablo de Olavide, Ed. 46, Ctra. de Utrera, km. 1, Seville 41013, Spain
| | - Soraya Zahedi
- Instituto de la Grasa, Spanish National Research Council (CSIC), Campus Universitario Pablo de Olavide, Ed. 46, Ctra. de Utrera, km. 1, Seville 41013, Spain
| | - Camila Abreu B Silva Rabelo
- Biological Processes Laboratory, São Carlos School of Engineering, University of São Paulo, 1100 João Dagnone Avenue, 13563-120 São Carlos, SP, Brazil
| | - Marcelo Zaiat
- Biological Processes Laboratory, São Carlos School of Engineering, University of São Paulo, 1100 João Dagnone Avenue, 13563-120 São Carlos, SP, Brazil
| | - Fernando G Fermoso
- Instituto de la Grasa, Spanish National Research Council (CSIC), Campus Universitario Pablo de Olavide, Ed. 46, Ctra. de Utrera, km. 1, Seville 41013, Spain
| | - Judith González-Arias
- Instituto de la Grasa, Spanish National Research Council (CSIC), Campus Universitario Pablo de Olavide, Ed. 46, Ctra. de Utrera, km. 1, Seville 41013, Spain; Inorganic Chemistry Department and Materials Sciences Institute, University of Seville-CSIC, Seville, Spain.
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2
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Rehman ZU, Ghaani M, Mohamed AYA, Gallagher J, Saikaly PE, Ali M. Alginate-like exopolysaccharides extracted from different waste sludges exhibit varying physicochemical and material properties. Front Microbiol 2024; 15:1493782. [PMID: 39564492 PMCID: PMC11573756 DOI: 10.3389/fmicb.2024.1493782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2024] [Accepted: 10/17/2024] [Indexed: 11/21/2024] Open
Abstract
This study examined the influence of different wastewater treatment processes on the physicochemical properties of Alginate-Like Exopolymers (ALE) extracted from waste sludge. Sludge samples were collected from wastewater treatment plants (WWTPs) processing both combined industrial and domestic wastewater, as well as domestic wastewater alone. Among the processes studied, aerobic granular sludge (AGS) produced the highest ALE yield (352 ± 50 mg/g-VSsludge), significantly exceeding that from membrane bioreactor (170 ± 41 mg/g-VSsludge) and conventional activated sludge (<130 mg/g-VSsludge). AGS-derived ALE also had the highest uronic acid content (224 ± 14.5 mg/g-VSsludge), with mannuronic acids playing a critical role in enhancing hydrogel cohesion and stability. The results showed that the distinct microbial consortium in the AGS system, including the presence of Pseudomonas alcaligenes, was strongly associated with increased ALE production. This establishes a novel link between microbial community composition and ALE yield. These insights are crucial for optimizing resource recovery in AGS systems and underscore the potential of ALE for various industrial applications.
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Affiliation(s)
- Zahid Ur Rehman
- Biological and Environmental Science and Engineering Division, Water Desalination and Reuse Research Center, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
- Research and Analytical Services Department, Saudi. Aramco, Dhahran, Saudi Arabia
| | - Masoud Ghaani
- Department of Civil, Structural and Environmental Engineering, Trinity College Dublin, The University of Dublin College Green, Dublin, Ireland
| | - Ahmed Y A Mohamed
- Department of Civil, Structural and Environmental Engineering, Trinity College Dublin, The University of Dublin College Green, Dublin, Ireland
| | - John Gallagher
- Department of Civil, Structural and Environmental Engineering, Trinity College Dublin, The University of Dublin College Green, Dublin, Ireland
- TrinityHaus Trinity Research Centre, Trinity College Dublin, Dublin, Ireland
| | - Pascal E Saikaly
- Biological and Environmental Science and Engineering Division, Water Desalination and Reuse Research Center, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Muhammad Ali
- Department of Civil, Structural and Environmental Engineering, Trinity College Dublin, The University of Dublin College Green, Dublin, Ireland
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Adekunle A, Ukaigwe S, Bezerra Dos Santos A, Iorhemen OT. Potential for curdlan recovery from aerobic granular sludge wastewater treatment systems - A review. CHEMOSPHERE 2024; 362:142504. [PMID: 38825243 DOI: 10.1016/j.chemosphere.2024.142504] [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: 03/15/2024] [Revised: 05/29/2024] [Accepted: 05/31/2024] [Indexed: 06/04/2024]
Abstract
The aerobic granular sludge (AGS) biotechnology has been explored for wastewater treatment for over two decades. AGS is gaining increased interest due to its enhanced treatment performance ability and the potential for resource recovery from AGS-based wastewater treatment systems. Resource recovery from AGS is a promising approach to sustainable wastewater treatment and attaining a circular economy in the wastewater management industry. Currently, research is at an advanced stage on recovering value-added resources such as phosphorus, polyhydroxyalkanoates, alginate-like exopolysaccharides, and tryptophan from waste aerobic granules. Recently, other value-added resources, including curdlan, have been identified in the aerobic granule matrix, and this may increase the sustainability of biotechnology in the wastewater industry. This paper provides an overview of AGS resource recovery potential. In particular, the potential for enhanced curdlan biosynthesis in the granule matrix and its recovery from AGS wastewater treatment systems is outlined.
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Affiliation(s)
- Adedoyin Adekunle
- School of Engineering, University of Northern British Columbia, 3333 University Way, Prince George, BC, V2N 4Z9, Canada
| | - Sandra Ukaigwe
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | - André Bezerra Dos Santos
- Department of Hydraulic and Environmental Engineering, Federal University of Ceará, Fortaleza, Ceará, Brazil
| | - Oliver Terna Iorhemen
- School of Engineering, University of Northern British Columbia, 3333 University Way, Prince George, BC, V2N 4Z9, Canada.
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Rosa-Masegosa A, Rodriguez-Sanchez A, Gorrasi S, Fenice M, Gonzalez-Martinez A, Gonzalez-Lopez J, Muñoz-Palazon B. Microbial Ecology of Granular Biofilm Technologies for Wastewater Treatment: A Review. Microorganisms 2024; 12:433. [PMID: 38543484 PMCID: PMC10972187 DOI: 10.3390/microorganisms12030433] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 02/15/2024] [Accepted: 02/19/2024] [Indexed: 04/02/2025] Open
Abstract
Nowadays, the discharge of wastewater is a global concern due to the damage caused to human and environmental health. Wastewater treatment has progressed to provide environmentally and economically sustainable technologies. The biological treatment of wastewater is one of the fundamental bases of this field, and the employment of new technologies based on granular biofilm systems is demonstrating success in tackling the environmental issues derived from the discharge of wastewater. The granular-conforming microorganisms must be evaluated as functional entities because their activities and functions for removing pollutants are interconnected with the surrounding microbiota. The deep knowledge of microbial communities allows for the improvement in system operation, as the proliferation of microorganisms in charge of metabolic roles could be modified by adjustments to operational conditions. This is why engineering must consider the intrinsic microbiological aspects of biological wastewater treatment systems to obtain the most effective performance. This review provides an extensive view of the microbial ecology of biological wastewater treatment technologies based on granular biofilms for mitigating water pollution.
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Affiliation(s)
- Aurora Rosa-Masegosa
- Department of Microbiology, Faculty of Pharmacy, University of Granada, 18071 Granada, Spain; (A.R.-M.); (A.R.-S.); (A.G.-M.); (J.G.-L.)
| | - Alejandro Rodriguez-Sanchez
- Department of Microbiology, Faculty of Pharmacy, University of Granada, 18071 Granada, Spain; (A.R.-M.); (A.R.-S.); (A.G.-M.); (J.G.-L.)
| | - Susanna Gorrasi
- Department of Ecological and Biological Sciences (DEB), University of Tuscia, 01100 Viterbo, Italy; (S.G.); (M.F.)
| | - Massimiliano Fenice
- Department of Ecological and Biological Sciences (DEB), University of Tuscia, 01100 Viterbo, Italy; (S.G.); (M.F.)
| | - Alejandro Gonzalez-Martinez
- Department of Microbiology, Faculty of Pharmacy, University of Granada, 18071 Granada, Spain; (A.R.-M.); (A.R.-S.); (A.G.-M.); (J.G.-L.)
| | - Jesus Gonzalez-Lopez
- Department of Microbiology, Faculty of Pharmacy, University of Granada, 18071 Granada, Spain; (A.R.-M.); (A.R.-S.); (A.G.-M.); (J.G.-L.)
| | - Barbara Muñoz-Palazon
- Department of Ecological and Biological Sciences (DEB), University of Tuscia, 01100 Viterbo, Italy; (S.G.); (M.F.)
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Liu S, Zhou M, Daigger GT, Huang J, Song G. Granule formation mechanism, key influencing factors, and resource recycling in aerobic granular sludge (AGS) wastewater treatment: A review. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 338:117771. [PMID: 37004484 DOI: 10.1016/j.jenvman.2023.117771] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Revised: 03/14/2023] [Accepted: 03/18/2023] [Indexed: 06/19/2023]
Abstract
The high-efficiency and additionally economic benefits generated from aerobic granular sludge (AGS) wastewater treatment have led to its increasing popularity among academics and industrial players. The AGS process can recycle high value-added biomaterials including extracellular polymeric substances (EPS), sodium alginate-like external polymer (ALE), polyhydroxyfatty acid (PHA), and phosphorus (P), etc., which can serve various fields including agriculture, construction, and chemical while removing pollutants from wastewaters. The effects of various key operation parameters on formation and structural stability of AGS are comprehensively summarized. The degradable metabolism of typical pollutants and corresponding microbial diversity and succession in the AGS wastewater treatment system are also discussed, especially with a focus on emerging contaminants removal. In addition, recent attempts for potentially effective production of high value-added biomaterials from AGS are proposed, particularly concerning improving the yield, quality, and application of these biomaterials. This review aims to provide a reference for in-depth research on the AGS process, suggesting a new alternative for wastewater treatment recycling.
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Affiliation(s)
- Shuli Liu
- School of Environmental and Municipal Engineering, North China University of Water Resources and Electric Power, Zhengzhou, 450000, China; Zhongzhou Water Holding Co., Ltd., Zhengzhou, 450046, China; Civil and Environmental Engineering, University of Michigan, 2350 Hayward St, G.G. Brown Building, Ann Arbor, MI, 48109, USA.
| | - Miao Zhou
- School of Environmental and Municipal Engineering, North China University of Water Resources and Electric Power, Zhengzhou, 450000, China.
| | - Glen T Daigger
- Civil and Environmental Engineering, University of Michigan, 2350 Hayward St, G.G. Brown Building, Ann Arbor, MI, 48109, USA.
| | - Jianping Huang
- School of Environmental and Municipal Engineering, North China University of Water Resources and Electric Power, Zhengzhou, 450000, China.
| | - Gangfu Song
- School of Environmental and Municipal Engineering, North China University of Water Resources and Electric Power, Zhengzhou, 450000, China; Zhongzhou Water Holding Co., Ltd., Zhengzhou, 450046, China.
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Chen X, Lee YJ, Yuan T, Lei Z, Adachi Y, Zhang Z, Lin Y, van Loosdrecht MCM. A review on recovery of extracellular biopolymers from flocculent and granular activated sludges: Cognition, key influencing factors, applications, and challenges. BIORESOURCE TECHNOLOGY 2022; 363:127854. [PMID: 36067889 DOI: 10.1016/j.biortech.2022.127854] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 08/21/2022] [Accepted: 08/22/2022] [Indexed: 06/15/2023]
Abstract
A reasonable recovery of excess sludge may shift the waste into wealth. Recently an increasing attention has been paid to the recycling of extracellular biopolymers from conventional and advanced biological wastewater treatment systems such as flocculent activated sludge (AS), bacterial aerobic granular sludge (AGS), and algal-bacterial AGS processes. This review provides the first overview of current research developments and future directions in the recovery and utilization of high value-added biopolymers from the three types of sludge. It details the discussion on the recent evolvement of cognition or updated knowledge on functional extracellular biopolymers, as well as a comprehensive summary of the operating conditions and wastewater parameters influencing the yield, quality, and functionality of alginate-like exopolymer (ALE). In addition, recent attempts for potential practical applications of extracellular biopolymers are discussed, suggesting research priorities for overcoming identification challenges and future prospects.
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Affiliation(s)
- Xingyu Chen
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Yu-Jen Lee
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Tian Yuan
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Zhongfang Lei
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan.
| | - Yasuhisa Adachi
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Zhenya Zhang
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8572, Japan
| | - Yuemei Lin
- Department of Biotechnology, Delft University of Technology, van der Maasweg 9, 2629 HZ, Delft, the Netherlands
| | - Mark C M van Loosdrecht
- Department of Biotechnology, Delft University of Technology, van der Maasweg 9, 2629 HZ, Delft, the Netherlands
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Núñez-Delgado A, Dominguez JR, Zhou Y, Race M. New trends on green energy and environmental technologies, with special focus on biomass valorization, water and waste recycling: editorial of the special issue. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 316:115209. [PMID: 35533594 DOI: 10.1016/j.jenvman.2022.115209] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 04/30/2022] [Indexed: 06/14/2023]
Abstract
In this editorial piece, the Editors of the Virtual Special Issue (VSI) "New Trends on Green Energy and Environmental Technologies, with Special Focus on Biomass Valorization, Water and Waste Recycling", present summarized data corresponding to the accepted submissions, as well as additional comments regarding the thematic of the VSI. Overall, 83 manuscripts were received, with final publication of those having the highest quality, accepted after peer-reviewing. The Editors think that the result is a set of very interesting papers that increase the knowledge on the matter, and which would be useful for researchers and the whole society.
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Affiliation(s)
- Avelino Núñez-Delgado
- Dept. Soil Sci. and Agric. Chem., Univ. Santiago de Compostela, Engineering Polytech. School, Campus Univ. S/n, 27002, Lugo, Spain.
| | - Joaquín R Dominguez
- Department of Chemical Engineering and Physical Chemistry, University of Extremadura, Spain
| | - Yaoyu Zhou
- College of Resources and Environment, Hunan Agricultural University, Changsha, 410128, Hunan Province, China
| | - Marco Race
- Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Via di Biasio 43, 03043, Cassino, Italy
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Ilmasari D, Kamyab H, Yuzir A, Riyadi FA, Khademi T, Al-Qaim FF, Kirpichnikova I, Krishnan S. A Review of the Biological Treatment of Leachate: Available Technologies and Future Requirements for the Circular Economy Implementation. Biochem Eng J 2022. [DOI: 10.1016/j.bej.2022.108605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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9
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Renfrew D, Vasilaki V, McLeod A, Lake A, Danishvar S, Katsou E. Where is the greatest potential for resource recovery in wastewater treatment plants? WATER RESEARCH 2022; 220:118673. [PMID: 35649294 DOI: 10.1016/j.watres.2022.118673] [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: 11/23/2021] [Revised: 04/28/2022] [Accepted: 05/23/2022] [Indexed: 06/15/2023]
Abstract
The restorative and regenerative ability of the circular economy has led to the rapid growth of this concept over the past decade, as it facilitates the broadly adopted principles of sustainable development and beyond, through restorative and regenerative actions. The water sector is poised to benefit from this transition, due to its intrinsic circularity and the resources it handles, predominantly found in wastewater, that are valuable and critical. Currently, the vast range of resource recovery technologies coupled with few industrial examples hinder strategic decision making. Resource recovery on a regional scale improves market share and mitigates investment risk, therefore, a structured approach has been developed for the selection of priority technologies to act as a guide for strategic planning. A representative UK wastewater model acts as the baseline, with multi-criteria analysis used to select resources and create an enhanced resource recovery scenario. It was found that implementing the recovery of 5 'priority resources' (and technology pathways) increased nitrogen and phosphorus recovery by 68% and 71%, respectively. Lastly, the need for a cross-cutting approach for the holistic assessment of circular solutions is discussed.
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Affiliation(s)
- D Renfrew
- Department of Civil & Environmental Engineering, Institute of Environment, Health and Societies, Brunel University London, Uxbridge Campus, Middlesex, UB8 3PH, Uxbridge, UK
| | - V Vasilaki
- Department of Civil & Environmental Engineering, Institute of Environment, Health and Societies, Brunel University London, Uxbridge Campus, Middlesex, UB8 3PH, Uxbridge, UK
| | - A McLeod
- Jacobs Engineering Group Inc. 2nd Floor Cottons Centre, Cottons Lane, London, SE1 2QG, England
| | - A Lake
- Jacobs Engineering Group Inc. 2nd Floor Cottons Centre, Cottons Lane, London, SE1 2QG, England
| | - S Danishvar
- Digital Manufacturing Centre at College of Engineering, Design and Physical Sciences, Brunel University London, Uxbridge Campus, Middlesex, UB8 3PH, Uxbridge, UK
| | - E Katsou
- Department of Civil & Environmental Engineering, Institute of Environment, Health and Societies, Brunel University London, Uxbridge Campus, Middlesex, UB8 3PH, Uxbridge, UK.
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Amin Vieira da Costa NP, Libardi N, Ribeiro da Costa RH. How can the addition of extracellular polymeric substances (EPS)-based bioflocculant affect aerobic granular sludge (AGS)? JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 310:114807. [PMID: 35231689 DOI: 10.1016/j.jenvman.2022.114807] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 01/19/2022] [Accepted: 02/23/2022] [Indexed: 06/14/2023]
Abstract
The ability of extracellular polymeric substances (EPS) recovered from aerobic granular sludge (AGS) to act as bioflocculant was tested in a pilot-scale sequencing batch reactor (SBR), fed with low-strength municipal wastewater. EPS were compared with the addition of Na-alginate as a standardized biopolymer. The optimal dosage of both biopolymers was determined through jar-test assays (400 mg L-1 of Na-alginate in a 250 mg Ca L-1 and 50 mg L-1 of EPS in pH of 2 ± 0.2). The addition of Na-alginate (Operational Period I- OP-I) and EPS (Operational Period II - OP-II) led to increased adhesion of particles with 2.9 ± 0.45 and 1.3 ± 0.3 g TSS L-1 during OP-I and OP-II, respectively, and fast settling biomass (SVI30 between 68 and 78 mL g-1). Granule predominance occurred at early stages of OP-I (day 37) and OP-II (day 44), presenting diameters mainly within the 212-600 μm range. The reactor showed removal efficiencies of 85% for biochemical oxygen demand (BOD) and above 50% for N-NH4 during the study periods. Furthermore, the addition of EPS as a bioflocculant promoted a substantial increase in polysaccharides (PS = 153.01 ± 121 mg gVSS-1) and proteins (PN = 121.96 ± 69 mg gVSS-1), while the addition of Na-alginate affected mostly the PS content (87 ± 24 mg gVSS-1). The microbial community shifted mainly from Betaproteobacteria (45%) during OP-I to Alphaproteobacteria (64%) in OP-II. Therefore, EPS affected both physical-chemical and microbial features of the AGS biomass without any change in treatment efficiencies. EPS is a promising resource to be recovered from aerobic granular sludge and to be used as an alternative and sustainable bioflocculant.
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Affiliation(s)
| | - Nelson Libardi
- Department of Sanitary and Environmental Engineering, Federal University of Santa Catarina - UFSC, 88040-970, Florianópolis, Brazil.
| | - Rejane Helena Ribeiro da Costa
- Department of Sanitary and Environmental Engineering, Federal University of Santa Catarina - UFSC, 88040-970, Florianópolis, Brazil
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