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Andersson SL, Baresel C, Andersson S, Westling K, Eriksson M, Munoz AC, Persson G, Narongin-Fujikawa M, Johansson K, Rydberg T. Chemical-Saving Potential for Membrane Bioreactor (MBR) Processes Based on Long-Term Pilot Trials. MEMBRANES 2024; 14:126. [PMID: 38921493 PMCID: PMC11205864 DOI: 10.3390/membranes14060126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Revised: 05/11/2024] [Accepted: 05/23/2024] [Indexed: 06/27/2024]
Abstract
Membrane bioreactors (MBRs) have gained attraction in municipal wastewater treatment because of their capacity to meet strict water quality standards and support water reuse. Despite this, their operational sustainability is often compromised by high resource consumption, especially regarding the use of chemicals for membrane cleaning. This study explores innovative membrane-cleaning strategies to enhance the sustainability of MBR processes. Through long-term pilot trials at Stockholm's largest wastewater treatment plant, this study showed that alternative cleaning strategies can reduce chemical use by up to 75% without sacrificing treatment performance. The results further suggest that these alternative strategies could result in cost reductions of up to 70% and a reduction in environmental impacts by as much as 95% for certain indicators. Given that MBRs play a crucial role in addressing increasing treatment demands and advancing circular water management, the outcomes of this study are beneficial for the broader adoption of MBR processes. These results also have implications for existing installations, offering a pathway to more sustainable wastewater treatment. Moreover, the presented cleaning strategies provide significant opportunities for lowering operational costs and reducing the environmental footprint of new and existing MBR installations.
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Affiliation(s)
| | - Christian Baresel
- IVL Swedish Environmental Research Institute, P.O. Box 21060, 100 31 Stockholm, Sweden (T.R.)
| | - Sofia Andersson
- Sweco Environment, Gjörwellsgatan 22, 112 60 Stockholm, Sweden
| | | | - Mikael Eriksson
- IVL Swedish Environmental Research Institute, P.O. Box 21060, 100 31 Stockholm, Sweden (T.R.)
| | - Andrea Carranza Munoz
- IVL Swedish Environmental Research Institute, P.O. Box 21060, 100 31 Stockholm, Sweden (T.R.)
| | | | | | - Kristin Johansson
- IVL Swedish Environmental Research Institute, P.O. Box 21060, 100 31 Stockholm, Sweden (T.R.)
| | - Tomas Rydberg
- IVL Swedish Environmental Research Institute, P.O. Box 21060, 100 31 Stockholm, Sweden (T.R.)
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2
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Kim J, Bae E, Park H, Park HJ, Shah SSA, Lee K, Lee J, Oh HS, Park PK, Shin YC, Moon H, Naddeo V, Choo KH. Membrane reciprocation and quorum quenching: An innovative combination for fouling control and energy saving in membrane bioreactors. WATER RESEARCH 2024; 250:121035. [PMID: 38154339 DOI: 10.1016/j.watres.2023.121035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 11/27/2023] [Accepted: 12/18/2023] [Indexed: 12/30/2023]
Abstract
Membrane bioreactors (MBRs) play a crucial role in wastewater treatment, but they face considerable challenges due to fouling. To tackle this issue, innovative strategies are needed. This study investigated the effectiveness of membrane reciprocation and quorum quenching (QQ) to control fouling in MBRs. The study compared MBRs using membrane reciprocation (30 rpm) and QQ (injecting media containing 100 or 200 mg/L BH4) with conventional MBRs employing different air-scouring intensities. The results demonstrated that combining membrane reciprocation (30 rpm) with QQ (200 mg/L BH4) significantly extended the service time of MBRs, making it approximately six times longer than conventional methods. Moreover, this approach reduced physically reversible resistance. The reduction in signal molecules related to biofouling due to QQ showcased its critical role in controlling biofouling, even under high shear caused by membrane reciprocation. However, the impact of QQ on microbial community structure appeared relatively insignificant when compared to factors such as operation time, aeration intensity, and membrane reciprocation. By combining membrane reciprocation and QQ, the study achieved a remarkable 81 % energy saving compared to extensive aeration (103 s-1 in velocity gradient), in addition to the extended service time. Importantly, this combined antifouling approach did not negatively affect microbial characteristics and wastewater treatment, emphasizing its effectiveness in MBRs. Overall, the findings of this study offer valuable insights for developing synergistic fouling control strategies in MBRs, significantly improving the energy efficiency of the wastewater treatment process.
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Affiliation(s)
- Jinwoo Kim
- School of Architectural, Civil, Environmental, and Energy Engineering, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea
| | - Eunjin Bae
- School of Architectural, Civil, Environmental, and Energy Engineering, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea; Daegu Metropolitan City Waterworks Headquarters (Water Quality Research Institute), 176 Dangsan-ro, Dalseo-gu, Daegu 42650, Republic of Korea
| | - Hyeona Park
- Advanced Institute of Water Industry, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea
| | - Hyung-June Park
- School of Architectural, Civil, Environmental, and Energy Engineering, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea
| | - Syed Salman Ali Shah
- School of Architectural, Civil, Environmental, and Energy Engineering, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea; Center for Water Research, Advanced Institute of Natural Sciences, Beijing Normal University at Zhuhai, Guangdong 519087, China
| | - Kibaek Lee
- Department of Biotechnology and Bioengineering, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Jaewoo Lee
- Department of Polymer-Nano Science and Technology, Jeonbuk National University, 567 Baekje-daero, Deokjin-gu, Jeonju 54896, Republic of Korea
| | - Hyun-Suk Oh
- Department of Environmental Engineering, Seoul National University of Science & Technology, Seoul 01811, Republic of Korea
| | - Pyung-Kyu Park
- Department of Environmental and Energy Engineering, Yonsei University, Wonju, Gangwon-do 26439, Republic of Korea
| | - Yong Cheol Shin
- HifilM, 24 Deokseongsandan 2-ro, Idong-eup, Cheoin-gu, Yongin, Gyeonggi-do 17130, Republic of Korea
| | - HeeWan Moon
- HifilM, 24 Deokseongsandan 2-ro, Idong-eup, Cheoin-gu, Yongin, Gyeonggi-do 17130, Republic of Korea
| | - Vincenzo Naddeo
- Sanitary Environmental Engineering Division, Department of Civil Engineering, University of Salerno, via Giovanni Paolo II, Fisciano, SA 84084, Italy
| | - Kwang-Ho Choo
- School of Architectural, Civil, Environmental, and Energy Engineering, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea; Advanced Institute of Water Industry, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea; Department of Environmental Engineering, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea.
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3
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Mannina G, Ni BJ, Makinia J, Harmand J, Alliet M, Brepols C, Ruano MV, Robles A, Heran M, Gulhan H, Rodriguez-Roda I, Comas J. Biological processes modelling for MBR systems: A review of the state-of-the-art focusing on SMP and EPS. WATER RESEARCH 2023; 242:120275. [PMID: 37413746 DOI: 10.1016/j.watres.2023.120275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 06/25/2023] [Accepted: 06/26/2023] [Indexed: 07/08/2023]
Abstract
A mathematical correlation between biomass kinetic and membrane fouling can improve the understanding and spread of Membrane Bioreactor (MBR) technology, especially in solving the membrane fouling issues. On this behalf, this paper, produced by the International Water Association (IWA) Task Group on Membrane modelling and control, reviews the current state-of-the-art regarding the modelling of kinetic processes of biomass, focusing on modelling production and utilization of soluble microbial products (SMP) and extracellular polymeric substances (EPS). The key findings of this work show that the new conceptual approaches focus on the role of different bacterial groups in the formation and degradation of SMP/EPS. Even though several studies have been published regarding SMP modelling, there still needs to be more information due to the highly complicated SMP nature to facilitate the accurate modelling of membrane fouling. The EPS group has seldom been addressed in the literature, probably due to the knowledge deficiency concerning the triggers for production and degradation pathways in MBR systems, which require further efforts. Finally, the successful model applications showed that proper estimation of SMP and EPS by modelling approaches could optimise membrane fouling, which can influence the MBR energy consumption, operating costs, and greenhouse gas emissions.
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Affiliation(s)
- Giorgio Mannina
- Engineering Department, Palermo University, Viale delle Scienze, Ed.8, 90128 Palermo, Italy.
| | - Bing-Jie Ni
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, New South Wales 2007, Australia
| | - Jacek Makinia
- Faculty of Civil and Environmental Engineering, Gdańsk University of Technology, ul. Narutowicza 11/12, 80-233 Gdańsk, Poland
| | | | - Marion Alliet
- Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France
| | - Christoph Brepols
- Erftverband, Wastewater Department, Am Erftverband 6, 50126 Bergheim, Germany
| | - M Victoria Ruano
- Departament d'Enginyeria Química, Escola Tècnica Superior d'Enginyeria (ETSE-UV), Universitat de València, Avinguda de la Universitat s/n, 46100 Burjassot, València, Spain
| | - Angel Robles
- Departament d'Enginyeria Química, Escola Tècnica Superior d'Enginyeria (ETSE-UV), Universitat de València, Avinguda de la Universitat s/n, 46100 Burjassot, València, Spain
| | - Marc Heran
- Institut Européen des Membranes, IEM, Univ Montpellier, CNRS, ENSCM, Montpellier, France
| | - Hazal Gulhan
- Engineering Department, Palermo University, Viale delle Scienze, Ed.8, 90128 Palermo, Italy; Environmental Engineering Department, Civil Engineering Faculty, Istanbul Technical University, Ayazaga Campus, Maslak, 34469 Istanbul, Turkey
| | - Ignasi Rodriguez-Roda
- LEQUiA, Laboratory of Chemical and Environmental Engineering, University of Girona, Campus Montilivi, 17071 Girona, Spain
| | - Joaquim Comas
- LEQUiA, Laboratory of Chemical and Environmental Engineering, University of Girona, Campus Montilivi, 17071 Girona, Spain; Catalan Institute for Water Research (ICRA), Emili Grahit 101, 17003 Girona, Spain
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Vaishnav S, Saini T, Chauhan A, Gaur GK, Tiwari R, Dutt T, Tarafdar A. Livestock and poultry farm wastewater treatment and its valorization for generating value-added products: Recent updates and way forward. BIORESOURCE TECHNOLOGY 2023; 382:129170. [PMID: 37196748 DOI: 10.1016/j.biortech.2023.129170] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 05/07/2023] [Accepted: 05/10/2023] [Indexed: 05/19/2023]
Abstract
Livestock and poultry wastewater poses a potent risk factor for environmental pollution accelerating disease load and premature deaths. It is characterized by high chemical oxygen demand, biological oxygen demand, suspended solids, heavy metals, pathogens, and antibiotics, among other contaminants. These contaminants have a negative impact on the quality of soil, groundwater, and air, and is a potential hazard to human health. Depending on the specific characteristics of wastewater, such as the type and concentration of pollutants present; several physical, chemical and biological strategies have been developed for wastewater treatment. This review aims at providing comprehensive overview of the profiling of livestock wastewater from the dairy, swine and poultry sub-sectors along with the biological (annamox and genetically modified bacteria) and physico-chemical treatment methodologies, and valorisation for the generation of value-added products such as bioplastics, biofertilizers, biohydrogen and microalgal-microbial fuel cells. Additionally, future perspectives for efficient and sustainable wastewater treatment are contemplated.
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Affiliation(s)
- Sakshi Vaishnav
- Livestock Production and Management Section, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly 243 122, Uttar Pradesh, India
| | - Tapendra Saini
- Livestock Production and Management Section, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly 243 122, Uttar Pradesh, India
| | - Anuj Chauhan
- Livestock Production and Management Section, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly 243 122, Uttar Pradesh, India
| | - Gyanendra Kumar Gaur
- Livestock Production and Management Section, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly 243 122, Uttar Pradesh, India
| | - Rupasi Tiwari
- Livestock Production and Management Section, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly 243 122, Uttar Pradesh, India
| | - Triveni Dutt
- Livestock Production and Management Section, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly 243 122, Uttar Pradesh, India
| | - Ayon Tarafdar
- Livestock Production and Management Section, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly 243 122, Uttar Pradesh, India.
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5
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Application of heat-activated peroxydisulfate process for the chemical cleaning of fouled ultrafiltration membranes. CHINESE CHEM LETT 2023. [DOI: 10.1016/j.cclet.2023.108316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/14/2023]
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6
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Sohail N, Riedel R, Dorneanu B, Arellano-Garcia H. Prolonging the Life Span of Membrane in Submerged MBR by the Application of Different Anti-Biofouling Techniques. MEMBRANES 2023; 13:217. [PMID: 36837720 PMCID: PMC9962460 DOI: 10.3390/membranes13020217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Revised: 01/28/2023] [Accepted: 02/07/2023] [Indexed: 06/18/2023]
Abstract
The membrane bioreactor (MBR) is an efficient technology for the treatment of municipal and industrial wastewater for the last two decades. It is a single stage process with smaller footprints and a higher removal efficiency of organic compounds compared with the conventional activated sludge process. However, the major drawback of the MBR is membrane biofouling which decreases the life span of the membrane and automatically increases the operational cost. This review is exploring different anti-biofouling techniques of the state-of-the-art, i.e., quorum quenching (QQ) and model-based approaches. The former is a relatively recent strategy used to mitigate biofouling. It disrupts the cell-to-cell communication of bacteria responsible for biofouling in the sludge. For example, the two strains of bacteria Rhodococcus sp. BH4 and Pseudomonas putida are very effective in the disruption of quorum sensing (QS). Thus, they are recognized as useful QQ bacteria. Furthermore, the model-based anti-fouling strategies are also very promising in preventing biofouling at very early stages of initialization. Nevertheless, biofouling is an extremely complex phenomenon and the influence of various parameters whether physical or biological on its development is not completely understood. Advancing digital technologies, combined with novel Big Data analytics and optimization techniques offer great opportunities for creating intelligent systems that can effectively address the challenges of MBR biofouling.
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Affiliation(s)
- Noman Sohail
- Department of Biotechnology of Water Treatment, Brandenburg University of Technology Cottbus/Senftenberg, 03046 Cottbus, Germany
| | - Ramona Riedel
- Department of Biotechnology of Water Treatment, Brandenburg University of Technology Cottbus/Senftenberg, 03046 Cottbus, Germany
| | - Bogdan Dorneanu
- Department of Process and Plant Technology, Brandenburg University of Technology Cottbus/Senftenberg, 03046 Cottbus, Germany
| | - Harvey Arellano-Garcia
- Department of Process and Plant Technology, Brandenburg University of Technology Cottbus/Senftenberg, 03046 Cottbus, Germany
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7
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Liu YJ. Mitigation of membrane fouling of alginate with combined actions of aeration and powdered activated carbon: Fouling behaviors and mechanisms. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2022; 94:e10748. [PMID: 35703107 DOI: 10.1002/wer.10748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 05/03/2022] [Accepted: 05/25/2022] [Indexed: 06/15/2023]
Abstract
A laboratory-scale flat-sheet ceramic microfiltration membrane system was developed to investigate the membrane fouling behaviors and mechanisms of sodium alginate (SA) in the presence of aeration and powdered activated carbon (PAC). When the SA concentration increased from 20 to 500 mg/L, the permeate flux decreased by 81.7%, and the transmembrane pressure (TMP) and resistance increased 1.7 and 24.5 times, respectively. At an SA concentration of 500 mg/L, it was found that the membrane fouling tended to decrease with the increase in the aeration rate, indicating high control of the fouling by air scouring, while PAC-aeration scouring produced a significant improvement in the permeate flux with substantially reduced fouling. In the microfiltration of 500 mg/L SA at an air flow rate of 2.2 L/min and PAC concentrations of 40, 100, and 250 mg/L, the flux increased by 179.3%, 238.0%, and 302.7%, the TMP decreased by 32.6%, 34.8%, and 45.7%, and the cake and pore blocking resistance decreased by 78.0%, 85.1%, and 87.9%, respectively, compared to the corresponding values without PAC-aeration scouring. Intermediate blocking and complete blocking models were confirmed to elucidate the effect of aeration scouring and PAC-aeration scouring on the mitigation of membrane fouling by SA. PRACTITIONER POINTS: Air scouring was effective at mitigating membrane fouling of sodium alginate. The addition of PAC could alleviate membrane fouling of SA. Synergistic scouring by aeration and PAC offers a promising means for more-efficient and cost-effective control of membrane fouling. The fouling mechanisms in various scenarios were elucidated.
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Affiliation(s)
- Ya-Juan Liu
- College of Chemistry and Chemical Engineering, Shanxi Datong University, Datong City, P.R. China
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8
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Cui Y, Gao H, Yu R, Gao L, Zhan M. Biological-based control strategies for MBR membrane biofouling: a review. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2021; 83:2597-2614. [PMID: 34115616 DOI: 10.2166/wst.2021.168] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Membrane bioreactor (MBR) technology has been paid extensive attention for wastewater treatment because of its advantages of high effluent quality and minimized occupation space and sludge production. However, the membrane fouling is always an inevitable problem, which causes high operation and maintenance costs and prevents the wide use of MBR technology. The membrane biofouling is the most complicated and has relatively slow progress among all types of fouling. In recent years, many membrane biofouling control methods have been developed. Different from the physical or chemical methods, the biological-based strategies are not only more effective for membrane biofouling control, but also milder and more environment-friendly and, therefore, have been increasingly employed. This paper mainly focuses on the mechanism, unique advantages and development of biological-based control strategies for MBR membrane biofouling such as quorum quenching, uncoupling, flocculants and so on. The paper summarizes the up-to-date development of membrane biofouling control strategies, emphasizes the advantages and promising potential of biological-based ones, and points out the direction for future studies.
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Affiliation(s)
- Yin Cui
- Department of Environmental Science and Engineering, School of Energy and Environment, Wuxi Engineering Research Center of Taihu Lake Water Environment, Southeast University, Nanjing, Jiangsu 210096, China and Key Laboratory of Environmental Medicine Engineering, Ministry of Education, Southeast University, Nanjing, Jiangsu 210009, China E-mail:
| | - Huan Gao
- Department of Environmental Science and Engineering, School of Energy and Environment, Wuxi Engineering Research Center of Taihu Lake Water Environment, Southeast University, Nanjing, Jiangsu 210096, China and Key Laboratory of Environmental Medicine Engineering, Ministry of Education, Southeast University, Nanjing, Jiangsu 210009, China E-mail:
| | - Ran Yu
- Department of Environmental Science and Engineering, School of Energy and Environment, Wuxi Engineering Research Center of Taihu Lake Water Environment, Southeast University, Nanjing, Jiangsu 210096, China and Key Laboratory of Environmental Medicine Engineering, Ministry of Education, Southeast University, Nanjing, Jiangsu 210009, China E-mail:
| | - Lei Gao
- Department of Environmental Science and Engineering, School of Energy and Environment, Wuxi Engineering Research Center of Taihu Lake Water Environment, Southeast University, Nanjing, Jiangsu 210096, China and Key Laboratory of Environmental Medicine Engineering, Ministry of Education, Southeast University, Nanjing, Jiangsu 210009, China E-mail:
| | - Manjun Zhan
- Nanjing Research Institute of Environmental Protection, Nanjing Environmental Protection Bureau, Nanjing, Jiangsu 210013, China
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A review of the current in-situ fouling control strategies in MBR: Biological versus physicochemical. J IND ENG CHEM 2021. [DOI: 10.1016/j.jiec.2021.03.042] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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10
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Direct membrane filtration of municipal wastewater: Linking periodical physical cleaning with fouling mechanisms. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2020.118125] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Wang H, Ma D, Shi W, Yang Z, Cai Y, Gao B. Formation of disinfection by-products during sodium hypochlorite cleaning of fouled membranes from membrane bioreactors. FRONTIERS OF ENVIRONMENTAL SCIENCE & ENGINEERING 2021; 15:102. [PMID: 33457041 PMCID: PMC7797181 DOI: 10.1007/s11783-021-1389-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 10/15/2020] [Accepted: 11/11/2020] [Indexed: 06/12/2023]
Abstract
UNLABELLED Periodic chemical cleaning with sodium hypochlorite (NaClO) is essential to restore the membrane permeability in a membrane bioreactor (MBR). However, the chlorination of membrane foulants results in the formation of disinfection by-products (DBPs), which will cause the deterioration of the MBR effluent and increase the antibiotic resistance in bacteria in the MBR tank. In this study, the formation of 14 DBPs during chemical cleaning offouled MBR membrane modules was investigated. Together with the effects of biofilm extracellular polymeric substances (EPS), influences of reaction time, NaClO dosage, initial pH, and cleaning temperature on the DBP formation were investigated. Haloacetic acids (HAAs) and trichloromethane (TCM), composed over 90% of the DBPs, were increasingly accumulated as the NaClO cleaning time extended. By increasing the chlorine dosage, temperature, and pH, the yield of TCM and dichloroacetic acid (DCAA) was increased by up to a factor of 1-14, whereas the yields of haloacetonitriles (HANs) and haloketones (HKs) were decreased. Either decreasing in the chlorine dosage and cleaning temperature or adjusting the pH of cleaning reagents toward acidic or alkaline could effectively reduce the toxic risks caused by DBPs. After the EPS extraction pretreatment, the formation of DBPs was accelerated in the first 12 h due to the damage of biofilm structure. Confocal laser scanning microscopy (CLSM) images showed that EPS, particularly polysaccharides, were highly resistant to chlorine and might be able to protect the cells exposed to chlorination. ELECTRONIC SUPPLEMENTARY MATERIAL Supplementary material is available in the online version of this article at 10.1007/s11783-021-1389-3 and is accessible for authorized users.
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Affiliation(s)
- Hao Wang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237 China
| | - Defang Ma
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237 China
| | - Weiye Shi
- No.1 Institute of Geology and Mineral Resources of Shandong Province, Jinan, 250014 China
- Shandong Engineering Laboratory for High-Grade Fe Ores Exploration and Exploitation, Jinan, 250014 China
| | - Zhiyu Yang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237 China
| | - Yun Cai
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237 China
| | - Baoyu Gao
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237 China
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12
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Wu M, Chen Y, Lin H, Zhao L, Shen L, Li R, Xu Y, Hong H, He Y. Membrane fouling caused by biological foams in a submerged membrane bioreactor: Mechanism insights. WATER RESEARCH 2020; 181:115932. [PMID: 32454321 DOI: 10.1016/j.watres.2020.115932] [Citation(s) in RCA: 120] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 05/10/2020] [Accepted: 05/11/2020] [Indexed: 06/11/2023]
Abstract
Though sludge foaming often occurs and thus causes serious membrane fouling in membrane bioreactors (MBRs), the fouling mechanisms related with the foaming phenomenon have not been well addressed, hindering better understanding and solving foaming problem. In this work, it was interestingly found that, the foulants during the foaming period possessed extremely high specific filtration resistance (SFR) (over 1016 m kg-1) and strong adhesion ability to membrane surface. Chemical characterization showed that the proteins (178.57 mg/L) and polysaccharides (209.21 mg/L) in the foaming sample were about 6.4 times and 5.4 times of those in the supernatant sample, suggesting existence of a mechanism permitting continuous production of these foulants in the MBR during the foaming period. It was revealed that the fouling caused by foams was associated with gel layer filtration process, and the extremely high SFR can be interpreted by chemical potential change in the gel filtration process depicted in Flory-Huggins theory. Meanwhile, analyses by the extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory showed that the strong adhesion ability stemmed from the high interaction energy between the foaming foulants and membrane surface. In addition, 16S rDNA gene sequencing identified that the abundance of the foaming related bacteria species in the sludge suspension during the foaming period was more than 10 times of that during the non-foaming period. This study offered new mechanism insights into foaming fouling in MBRs.
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Affiliation(s)
- Mengfei Wu
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, 321004, China
| | - Yifeng Chen
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, 321004, China
| | - Hongjun Lin
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, 321004, China.
| | - Leihong Zhao
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, 321004, China
| | - Liguo Shen
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, 321004, China
| | - Renjie Li
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, 321004, China
| | - Yanchao Xu
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, 321004, China
| | - Huachang Hong
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, 321004, China
| | - Yiming He
- Department of Materials Science and Engineering, Zhejiang Normal University, Jinhua, 321004, China
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