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Wang L, Al-Dhabi NA, Huang X, Luan Z, Tang W, Xu Z, Xu W. Suitability of inorganic coagulants for algae-laden water treatment: Trade-off between algae removal and cell viability, aggregate properties and coagulant residue. JOURNAL OF HAZARDOUS MATERIALS 2024; 471:134314. [PMID: 38640668 DOI: 10.1016/j.jhazmat.2024.134314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 03/13/2024] [Accepted: 04/14/2024] [Indexed: 04/21/2024]
Abstract
Inorganic coagulants could effectively precipitate algae cells but might increase the potential risks of cell damage and coagulant residue. This study was conducted to critically investigate the suitability of polyaluminum (PAC), FeCl3 and TiCl4 for algae-laden water treatment in terms of the trade-off between algal substance removal, cell viability, and coagulant residue. The results showed that an appropriate increase in coagulant dosage contributed to better coagulation performance but severe cell damage and a higher risk of intracellular organic matter (IOM) release. TiCl4 was the most destructive, resulting in 60.85% of the algal cells presenting membrane damage after coagulation. Intense hydrolysis reaction of Ti salts was favorable for the formation of larger and more elongated, dendritic structured flocs than Al and Fe coagulants. TiCl4 exhibited the lowest residue level and remained in the effluents mainly in colloidal form. The study also identified charge neutralization, chemisorption, enmeshment, and complexation as the dominant mechanisms for algae water coagulation by metal coagulants. Overall, this study provides the trade-off analyses between maximizing algae substance removal and minimizing potential damage to cell integrity and is practically valuable to develop the most suitable and feasible technique for algae-laden water treatment.
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Affiliation(s)
- Lili Wang
- School of Water Conservancy and Environment, University of Jinan, No. 336 Nanxinzhuang Western Road, Jinan 250022, Shandong, PR China
| | - Naif Abdullah Al-Dhabi
- Department of Botany and Microbiology, College of Science, King Saud University, P. O. Box 2455, Riyadh 11451, Saudi Arabia
| | - Xin Huang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Science, Chinese Academy of Science, No. 18 Shuangqing Road, Beijing 100085, PR China
| | - Zhiyuan Luan
- Jinan Environmental Research Institute, 25th Floor, Xinsheng Building, No. 1299 Xinluo Street, Jinan 250000, Shandong, PR China
| | - Wangwang Tang
- College of Environmental Science and Engineering, Hunan University, No. 8 Lushan South Road, Changsha 410082, Hunan, PR China
| | - Zhenghe Xu
- School of Water Conservancy and Environment, University of Jinan, No. 336 Nanxinzhuang Western Road, Jinan 250022, Shandong, PR China.
| | - Weiying Xu
- School of Water Conservancy and Environment, University of Jinan, No. 336 Nanxinzhuang Western Road, Jinan 250022, Shandong, PR China; Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Science, Chinese Academy of Science, No. 18 Shuangqing Road, Beijing 100085, PR China.
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2
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Bernardino EG, Ferreira MEC, Bergamasco R, Yamaguchi NU. Photocatalyst of manganese ferrite and reduced graphene oxide supported on activated carbon from cow bone for wastewater treatment. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:4779-4796. [PMID: 38105329 DOI: 10.1007/s11356-023-31501-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 12/05/2023] [Indexed: 12/19/2023]
Abstract
The present research aimed to evaluate the photocatalytic activity of manganese ferrite (M) and reduced graphene oxide (G) supported on pulverized activated carbon from cow bone waste (PAC-MG). PAC-MG was characterized by different instrumental techniques. The efficiency of PAC-MG was evaluated using solar irradiation under different conditions of photocatalyst concentration, H2O2 concentration, and pH ranges for the discoloration of methylene blue dye (MB). The synergy between the nanomaterials potentiated the photocatalytic activity, reaching 85.5% of MB discoloration when using 0.25 g L-1 of catalyst at neutral pH with no oxidant needed. Furthermore, PAC-MG demonstrated excellent stability in 6 consecutive cycles. Finally, it is expected that the present study can add value to industrial waste and contribute to the development of novel water and wastewater treatment methods, ensuring water quality for human consumption and the environment.
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Affiliation(s)
- Eduarda Gameleira Bernardino
- Post-Graduation Program in Clean Technologies, Cesumar Institute of Science, Technology, and Innovation, Cesumar University, Maringá, Brazil
| | | | - Rosângela Bergamasco
- Department of Chemical Engineering, State University of Maringá, Maringá, Brazil
| | - Natália Ueda Yamaguchi
- Post-Graduation Program in Clean Technologies, Cesumar Institute of Science, Technology, and Innovation, Cesumar University, Maringá, Brazil.
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3
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Wilson W, Yeboah B, Govender P. Evaluation of the suitability of integrated bone char- and biochar-treated groundwater for drinking using single-factor, Nemerow, and heavy metal pollution indexes. ENVIRONMENTAL MONITORING AND ASSESSMENT 2023; 195:647. [PMID: 37154981 DOI: 10.1007/s10661-023-11249-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Accepted: 04/13/2023] [Indexed: 05/10/2023]
Abstract
The treatment of contaminated groundwater using integrated bone char and biochar beds has been studied. The bone char and biochar were made in a locally built double-barrel retort utilising cow bones, coconut husks, bamboo, neem trees, and palm kernel shells at 450 °C and were graded into 0.05- and 0.315-mm sizes. Eight groundwater treatment experiments (BF2-BF9) were performed in columns with bed heights of 8.5-16.5 cm to remove nutrients, heavy metals, microorganisms, and interfering ions from groundwater using bone char, biochar, and a combination of bone and biochar. The water samples were analysed for twenty-one water quality parameters including pH, total dissolved solids, conductivity, turbidity, fluoride, chloride, sodium, and potassium. The rest were total coliforms, faecal coliforms, total heterotrophic bacteria, Escherichia coli, manganese, and total iron. The effectiveness of the treatment processes was assessed using the Ghana standard authority and the World Health Organisation's recommended values for drinking water quality. The results were shared using a simplified single-factor index, Nemerow's pollution index, and a heavy metal pollution index with decision-makers as a technology for groundwater treatment in rural communities in Africa. Bone char was more effective in removing total heterotrophic bacteria than any of the other treatment agents tested. This is because of its compact nature and small particle size. The quality of water treated by BF3, BF5, BF6, BF7, BF8, and BF9 was fit for drinking based on the single-factor and heavy-metal pollution evaluation because they have the lowest level of pollution. However, Nemerow pollution analysis found only BF5 to be the most suitable for public use.
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Affiliation(s)
- William Wilson
- Faculty of Science, Department of Chemical Sciences-DFC, University of Johannesburg, P. O. Box 17011, Johannesburg, South Africa.
- CSIR-Water Research Institute, Environmental Chemistry and Sanitation Engineering Division, P.O. Box AH 38, Achimota-Accra, Ghana.
| | - Boniface Yeboah
- CSIR-Institute of Industrial Research, Materials and Manufacturing Division, P. O. Box LG 576, Legon-Accra, Ghana
| | - Poomani Govender
- Faculty of Science, Department of Chemical Sciences-DFC, University of Johannesburg, P. O. Box 17011, Johannesburg, South Africa
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4
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Anderson LE, DeMont I, Dunnington DD, Bjorndahl P, Redden DJ, Brophy MJ, Gagnon GA. A review of long-term change in surface water natural organic matter concentration in the northern hemisphere and the implications for drinking water treatment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 858:159699. [PMID: 36306839 DOI: 10.1016/j.scitotenv.2022.159699] [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: 05/15/2022] [Revised: 10/20/2022] [Accepted: 10/20/2022] [Indexed: 06/16/2023]
Abstract
Reduced atmospheric acid deposition has given rise to recovery from acidification - defined as increasing pH, acid neutralization capacity (ANC), or alkalinity in surface waters. Strong evidence of recovery has been reported across North America and Europe, driving chemical responses. The primary chemical responses identified in this review were increasing concentration and changing character of natural organic matter (NOM) towards predominantly hydrophobic nature. The concentration of NOM also influenced trace metal cycling as many browning surface waters also reported increases in Fe and Al. Further, climate change and other factors (e.g., changing land use) act in concert with reductions in atmospheric deposition to contribute to widespread browning and will have a more pronounced effect as deposition stabilizes. The observed water quality trends have presented challenges for drinking water treatment (e.g., increased chemical dosing, poor filter operations, formation of disinfection by-products) and many facilities may be under designed as a result. This comprehensive review has identified key research areas to be addressed, including 1) a need for comprehensive monitoring programs (e.g., larger timescales; consistency in measurements) to assess climate change impacts on recovery responses and NOM dynamics, and 2) a better understanding of drinking water treatment vulnerabilities and the transition towards robust treatment technologies and solutions that can adapt to climate change and other drivers of changing water quality.
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Affiliation(s)
- Lindsay E Anderson
- Centre for Water Resources Studies, Department of Civil & Resource Engineering, Dalhousie University, 1360 Barrington St. Halifax, Nova Scotia, Canada.
| | - Isobel DeMont
- Centre for Water Resources Studies, Department of Civil & Resource Engineering, Dalhousie University, 1360 Barrington St. Halifax, Nova Scotia, Canada
| | - Dewey D Dunnington
- Centre for Water Resources Studies, Department of Civil & Resource Engineering, Dalhousie University, 1360 Barrington St. Halifax, Nova Scotia, Canada
| | - Paul Bjorndahl
- Department of Mathematics & Statistics, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Dave J Redden
- Centre for Water Resources Studies, Department of Civil & Resource Engineering, Dalhousie University, 1360 Barrington St. Halifax, Nova Scotia, Canada
| | | | - Graham A Gagnon
- Centre for Water Resources Studies, Department of Civil & Resource Engineering, Dalhousie University, 1360 Barrington St. Halifax, Nova Scotia, Canada
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5
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Abstract
Humic acid (HA) has complex molecular structure and is capable of adsorption, ion exchange, and chelation with organic and inorganic pollutants in water bodies, worsening water quality and jeopardizing human health and ecological environment. How to effectively remove HA from water is one of the research focuses of this paper. In this study, the UV-activated sodium perborate (SPB) synergistic system (UV/SPB) was established to eliminate HA in water. The effects of initial HA concentration, SPB dose, and initial pH value on the HA elimination were determined, and the main mechanisms of the synergy and HA degradation were explored. The outcomes show that the HA elimination ratio by the sole UV and only SPB system were only 0.5% and 1.5%, respectively. The HA removal of UV/SPB reached 88.8%, which can remove HA more effectively than other systems. Free radical masking experiment proved that hydroxyl radical produced by SPB activation is the main active substance for HA removal. The results of UV-vis absorption spectrum, absorbance ratio, specific UV absorbance, and excitation–emission matrix spectroscopy verified that the UV/SPB system can effectively decompose and mineralize HA.
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Chen Y, Qian Y, Ma J, Mao M, Qian L, An D. New insights into the cooperative adsorption behavior of Cr(VI) and humic acid in water by powdered activated carbon. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 817:153081. [PMID: 35038541 DOI: 10.1016/j.scitotenv.2022.153081] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 01/06/2022] [Accepted: 01/08/2022] [Indexed: 06/14/2023]
Abstract
Chromium and humic acid often co-exist in wastewater and source waters, and the removal of chromium through sorption by activated carbon may be greatly influenced by humic acid. In this study, we systematically evaluated concurrent adsorption of humic acid (HA) and hexavalent chromium (Cr(VI)) in water by powdered activated carbon (PAC) and further, the effect on conversion to trivalent chromium (Cr(III)). Adsorption of both HA and Cr(VI) was significantly enhanced in the dual adsorbate system as compared to treatments with HA or Cr(VI) alone. The removal of HA increased by 16.0% in the presence of 80 mg/L Cr(VI), while the removal of Cr(VI) similarly increased with increasing levels of HA. However, the promotion effect of HA was found to decrease with increasing pH. With HA at 20 mg/L, removal of Cr(VI) increased from 40.09% to 70.12% at pH 3, which was about twice the increase at pH 10. The cooperative adsorption mechanism was explored using scanning electron microscopy coupled with energy dispersive spectroscopy (SEM-EDS), Raman spectroscopy, Fourier transform infrared spectrometer (FTIR), and X-ray photoelectron spectroscopy (XPS). Comprehensive analysis of spectra suggested that the mutual promotion between HA and Cr(VI) adsorption was attributable to the formation of Cr(VI)-HA and Cr(III)-HA complexes that were readily adsorbed on the PAC surfaces. The higher HA concentrations increased the reduction of Cr(VI) to Cr(III), which was likely due to the electron transfer provided by the functional groups such as -CO, -OH and -COOH in both PAC and HA. At pH 3, 99.1% of Cr adsorbed on the PAC surface was in the form of Cr(III). These findings imply that the interactions between Cr(VI) and HA in the process of water treatment by PAC provides additional and synergistic benefits, leading to a greater removal of chromium.
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Affiliation(s)
- Yanan Chen
- Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, PR China
| | - Yunkun Qian
- Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, PR China
| | - Jiaxin Ma
- Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, PR China
| | - Mengjun Mao
- Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, PR China
| | - Linping Qian
- Department of Chemistry, Fudan University, Shanghai 200433, PR China
| | - Dong An
- Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China.
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7
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State-of-the-Art Review on the Application of Membrane Bioreactors for Molecular Micro-Contaminant Removal from Aquatic Environment. MEMBRANES 2022; 12:membranes12040429. [PMID: 35448399 PMCID: PMC9032214 DOI: 10.3390/membranes12040429] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Revised: 03/29/2022] [Accepted: 04/08/2022] [Indexed: 12/27/2022]
Abstract
In recent years, the emergence of disparate micro-contaminants in aquatic environments such as water/wastewater sources has eventuated in serious concerns about humans’ health all over the world. Membrane bioreactor (MBR) is considered a noteworthy membrane-based technology, and has been recently of great interest for the removal micro-contaminants. The prominent objective of this review paper is to provide a state-of-the-art review on the potential utilization of MBRs in the field of wastewater treatment and micro-contaminant removal from aquatic/non-aquatic environments. Moreover, the operational advantages of MBRs compared to other traditional technologies in removing disparate sorts of micro-contaminants are discussed to study the ways to increase the sustainability of a clean water supplement. Additionally, common types of micro-contaminants in water/wastewater sources are introduced and their potential detriments on humans’ well-being are presented to inform expert readers about the necessity of micro-contaminant removal. Eventually, operational challenges towards the industrial application of MBRs are presented and the authors discuss feasible future perspectives and suitable solutions to overcome these challenges.
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8
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Electrocoagulation vs. Integrate Electrocoagulation-Natural Zeolite for Treatment of Biowaste Compost Leachate—Whether the Optimum Is Truly Optimal. MINERALS 2022. [DOI: 10.3390/min12040442] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Natural zeolites are well-known materials widely applied in the environmental remediation treatment process. However, the integration of various treatment methods is exceedingly investigated for achieving satisfactory effluent quality. In this paper, the integration of electrocoagulation and natural zeolite was evaluated in the treatment of biowaste compost leachate in a single step. The influence of different distances of electrodes (1.5, 3, and 4.5 cm), stirring speed (70, 200, and 400 rpm), the addition of natural zeolite and electrolyte NaCl on the efficiency of treatment of biowaste compost leachate has been carried out. Process efficiency was evaluated by measuring the change of pH value, electrical conductivity, temperature, turbidity, chemical oxygen demand (COD), total Kjeldahl nitrogen (TNK), total solids, and sludge settling test. The Taguchi method was applied to optimize biowaste compost leachate treatment. Experiments are planned according to Taguchi’s L8 (24 41) orthogonal array. The stirring speed, electrode distance, electrolyte and zeolite addition, solution initial pH adjustment were chosen as controllable factors, and their impact on COD, turbidity, TNK, settling rate, and electrode consumption were studied. Results show that optimal conditions depend on the parameter of interest and that optimal values for a particular parameter are not always the optimum if the desired goal is considered.
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9
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De Carvalho Gomes S, Zhou JL, Zeng X, Long G. Water treatment sludge conversion to biochar as cementitious material in cement composite. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 306:114463. [PMID: 35007797 DOI: 10.1016/j.jenvman.2022.114463] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Revised: 01/02/2022] [Accepted: 01/05/2022] [Indexed: 06/14/2023]
Abstract
Water treatment sludge was successfully thermally converted to obtain biochar as a stable material with resource potential. This research explored the application of sludge biochar as a supplementary cementitious material. The cement paste samples incorporating different amounts of sludge biochar were prepared, hardened, and analyzed for performance. The results show an improvement in hydration kinetics and mechanical properties of cement paste incorporating biochar, compared to raw sewage sludge. The mineralogical, thermal and microscopic analyses show evidence of pozzolanic activity of the biochar. The samples with 2% and 5% biochar showed higher heat release than the reference material. Specimens with 1%, 2% and 5% biochar showed a slightly higher compressive strength at 28 days compared to the reference material. Sludge conversion to biochar will incur an estimated cost of US$398.23/ton, which is likely to be offset by the substantial benefits from avoiding landfill and saving valuable cementitious materials. Therefore, this research has demonstrated that through conversion to biochar, water treatment sludge can be promoted as a sustainable and alternative cementitious material for cement with minimum environmental impacts, hence contributing to circular economy.
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Affiliation(s)
- Samuel De Carvalho Gomes
- Center for Green Technology, School of Civil and Environmental Engineering, University of Technology Sydney, NSW 2007, Australia
| | - John L Zhou
- Center for Green Technology, School of Civil and Environmental Engineering, University of Technology Sydney, NSW 2007, Australia; School of Civil Engineering, Central South University, Changsha, Hunan Province, 410075, China.
| | - Xiaohui Zeng
- School of Civil Engineering, Central South University, Changsha, Hunan Province, 410075, China
| | - Guangcheng Long
- School of Civil Engineering, Central South University, Changsha, Hunan Province, 410075, China
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10
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Lee KH, Qasim M, Lee KG, Inam MA, Khan IA, Khan R, Wie YM. Use of ballasted flocculation (BF) sludge for the manufacturing of lightweight aggregates. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 305:114379. [PMID: 34959062 DOI: 10.1016/j.jenvman.2021.114379] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 12/19/2021] [Accepted: 12/21/2021] [Indexed: 06/14/2023]
Abstract
Ballasted flocculation (BF) is an efficient way to remove the turbidity from surface water. The objective of the present study is to optimize the ballast (magnetite), coagulant (poly aluminum chloride) concentration and pH for efficient turbidity removal from surface water. To do this, the sludge produced from an optimized dose of a BF treatment was utilized for the production of lightweight (LW) aggregates by combining it with hard clay and sewage sludge. The LW aggregates were formed by means of rapid sintering in the temperature range of 1000-1200 °C with an exposure time of 10 min. The physical properties of the LW aggregates, in this case the leaching of heavy metals, the bulk density and the microstructure, were investigated. The results indicated that corresponding ballast and coagulant concentrations of 0.75 g/L and 30 mg/L (poly aluminum chloride (PAC)) resulted in the maximum removal efficiency of ≈95%. Using a mixture of BF sludge (30 wt%), dry sewage sludge (20 wt%), and hard clay (50 wt%), aggregates with a density of around 1.0 g/cm3 could be produced. In addition, it was confirmed that the manufactured aggregate was environmentally stable as the elution of heavy metals was suppressed.
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Affiliation(s)
- Kang Hoon Lee
- Department of Civil &Environmental Engineering, Hanyang University, 222 Seongdong-gu, Seoul, 04763, South Korea.
| | - Muhammad Qasim
- Department of Civil &Environmental Engineering, Hanyang University, 222 Seongdong-gu, Seoul, 04763, South Korea.
| | - Ki Gang Lee
- Department of Materials Engineering, Kyonggi University, Suwon, Gyeonggi-do, 16227, South Korea.
| | - Muhammad Ali Inam
- Institute of Environmental Sciences and Engineering (IESE), School of Civil and Environmental Engineering (SCEE), H-12 Campus, National University of Sciences and Technology (NUST), Islamabad, 44000, Pakistan.
| | - Imtiaz Afzal Khan
- Department of Civil &Environmental Engineering, Hanyang University, 222 Seongdong-gu, Seoul, 04763, South Korea.
| | - Rizwan Khan
- Department of Chemical Engineering, Quaid-e-Awam University of Engineering, Science and Technology (QUEST), Nawabshah, 67480, Pakistan.
| | - Young Min Wie
- Department of Materials Engineering, Kyonggi University, Suwon, Gyeonggi-do, 16227, South Korea.
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11
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Unraveling the role of ballast surface charge at floc growth behavior in ballasted flocculation. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2021.119507] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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12
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Jiang W, Yu Z, Cao X, Jiang K, Yuan Y, Anderson DM, Song X. Effects of soluble organics on the settling rate of modified clay and development of improved clay formulations for harmful algal bloom control. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 289:117964. [PMID: 34426199 DOI: 10.1016/j.envpol.2021.117964] [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: 04/24/2021] [Revised: 08/09/2021] [Accepted: 08/11/2021] [Indexed: 06/13/2023]
Abstract
For many years, the dispersal of modified clay (MC) has been used to control harmful algal blooms (HABs) in coastal waters of China. MC flocculation efficiency can be influenced by many factors in variable and complex natural environments, including high concentrations of dissolved organic matter (DOM) in the water to be treated. Since many HABs occur in nearshore waters where DOM concentrations are high, this is a significant problem that requires urgent attention. This study involved the use of humic acid as a representative form of DOM to study the influence of organic matter on the MC flocculation process. At high concentrations, humic acid was adsorbed onto MC particles, resulting in a decrease in surface potential and an increase in electrostatic repulsion between the clay particles; this decreased the MC settling rate and increased the water clarification time. Flocs were characterized by their relatively small particle size, high particle concentration, and low collision efficiency, which together resulted in slow clarification of the water after MC spraying. Based on the mechanism of the DOM-MC interaction and combined with the Derjaguin-Landau-Verwey-Overbeek theory and theoretical considerations of clay surface modification, the "ionic atmosphere compression" method was used to improve MC flocculation efficiency in high-organic water. This method increased the ionic strength of the clay stock solution by adding salt, thereby compressing the ionic atmosphere of MC particles and lowering the potential barrier, allowing the MC particles in the treated water to flocculate rapidly and form large flocs, followed by further floc growth and rapid settling via differential sedimentation. The settling rate of MCs improved by a factor of two and the removal efficiency of the HAB cells increased by 7-28%. This study provides important baseline information that will extend the application of MC to HAB control in water bodies with high organic loadings.
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Affiliation(s)
- Wenbin Jiang
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China; Functional Laboratory of Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, PR China
| | - Zhiming Yu
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China; Functional Laboratory of Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, PR China.
| | - Xihua Cao
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China; Functional Laboratory of Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, PR China
| | - Kaiqin Jiang
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China; Functional Laboratory of Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, PR China
| | - Yongquan Yuan
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China; Functional Laboratory of Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, PR China
| | | | - Xiuxian Song
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China; Functional Laboratory of Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Center for Ocean Mega-Science, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao, 266071, PR China
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13
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Shoparwe NF, Kee LC, Otitoju TA, Shukor H, Zainuddin N, Makhtar MMZ. Removal of Humic Acid Using 3-Methacryloxypropyl Trimethoxysilane Functionalized MWCNT Loaded TiO 2/PES Hybrid Membrane. MEMBRANES 2021; 11:721. [PMID: 34564538 PMCID: PMC8470582 DOI: 10.3390/membranes11090721] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 09/03/2021] [Accepted: 09/14/2021] [Indexed: 11/17/2022]
Abstract
In the present work, a highly efficient mixed matrix membrane (MMM) for humic acid (HA) removal was developed. Multiwalled carbon nanotubes (MWCNTs) were functionalized in the presence of 3-methacryloxypropyl trimethoxysilane using the co-condensation method and were subsequently loaded with TiO2 (prepared via the sol-gel route). The as-prepared material was then incorporated into a PES polymer solution to prepare a fMWCNT-TiO2/PES hybrid membrane via non-solvent induced phase inversion. The microstructure of the membrane was characterized using Fourier transform infrared spectroscopy, atomic force microscopy, scanning electron microscopy, water contact angle, thickness, porosity, and pore size. The fMWCNT-TiO2/PES hybrid membrane was tested for the removal of HA and antifouling performance. The results show that the surface hydrophilicity of the membranes was greatly improved upon the addition of the fMWCNT-TiO2 particles. The results show that 92% of HA was effectively removed after 1 h of filtration. In comparison with pristine membrane, the incorporation of fMWCNT-TiO2 nanoparticles led to enhanced pure water flux (99.05 L/m2 h), permeate flux (62.01 L/m2 h), higher HA rejection (92%), and antifouling improvement (RFR: 37.40%, FRR: 86.02%). Thus, the fMWCNT-TiO2/PES hybrid membrane is considered to be a great potential membrane for the improvement of ultrafiltration membranes.
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Affiliation(s)
- Noor Fazliani Shoparwe
- Faculty of Bioengineering and Technology, Jeli Campus, Universiti Malaysia Kelantan, Jeli 17600, Kelantan, Malaysia; (N.F.S.); (L.-C.K.); (T.A.O.)
| | - Lim-Cee Kee
- Faculty of Bioengineering and Technology, Jeli Campus, Universiti Malaysia Kelantan, Jeli 17600, Kelantan, Malaysia; (N.F.S.); (L.-C.K.); (T.A.O.)
| | - Tunmise Ayode Otitoju
- Faculty of Bioengineering and Technology, Jeli Campus, Universiti Malaysia Kelantan, Jeli 17600, Kelantan, Malaysia; (N.F.S.); (L.-C.K.); (T.A.O.)
- School of Materials Science and Engineering, Shenyang University of Technology, Shenyang 110870, China
| | - Hafiza Shukor
- Centre of Excellence For Biomass Utilization (CoEBU), Faculty of Chemical Engineering Technology, Universiti Malaysia Perlis, Arau 02600, Perlis, Malaysia;
| | - Nor’Izzah Zainuddin
- Indah Water Konsortium, Lorong Perda Utama 13, Bukit Mertajam 14300, Pulau Pinang, Malaysia;
| | - Muaz Mohd Zaini Makhtar
- Bioprocess Technology Division, School of Industrial Technology, Universiti Sains Malaysia, Gelugor 11800, Pulau Pinang, Malaysia
- Fellow of Center for Global Sustainability Studies, Universiti Sains Malaysia, Gelugor 11800, Pulau Pinang, Malaysia
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14
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Yue Y, An G, Liu L, Lin L, Jiao R, Wang D. Pre-aggregation of Al 13 in optimizing coagulation for removal of humic acid. CHEMOSPHERE 2021; 277:130268. [PMID: 33774233 DOI: 10.1016/j.chemosphere.2021.130268] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2020] [Revised: 03/01/2021] [Accepted: 03/05/2021] [Indexed: 06/12/2023]
Abstract
The effective removal of humic acid (HA) by coagulation has been extensively investigated for water treatments. However, the limitations of pH variation and excessive residual aluminum issues were still factors needed to be considered. In this study, to investigate the coagulation mechanism for removing HA by Al13 and optimize Al13 operation for removing HA, Al13 and preformed Al13 aggregates (Al13agg) were applied to remove HA at different pH conditions. The results showed that preformed Al13agg exhibited superior HA removal performance than Al13 due to its wide pH range and low residual Al level. During coagulation, Al13 and Al13agg interacted with HA in their original status, but the DSlope325-375 difference implied that the complexation capacity between HA and Al13agg was stronger than Al13. The new peaks of HPSEC representing larger molecular weight substances were formed under acidic and neutral conditions, which indicated that HA firstly aggregated into larger complexed molecules by interacting with Al13 or its hydrolysates and was subsequently removed by forming large flocs which was completely different from Al13agg situation. Therefore, the different coagulation mechanisms played the roles in HA removal for Al13 and Al13agg which were studied in this paper. It was believed that the complexation and charge neutralization effects dominated coagulation process for Al13 while sweep flocculation and adsorption coagulation were main driving force for Al13agg in HA removing. This work provides significant understanding of HA removal by Al13 and Al13agg coagulation, which can help to design and optimize the high efficiency coagulant based on Al polycations.
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Affiliation(s)
- Ye Yue
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Guangyu An
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China.
| | - Libing Liu
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Leiming Lin
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Ruyuan Jiao
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; Yangtze River Delta Branch, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Yiwu, Zhejiang, 322000, China
| | - Dongsheng Wang
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Yangtze River Delta Branch, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Yiwu, Zhejiang, 322000, China.
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15
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Magnetic composite Ca(OH)2/Fe3O4 for highly efficient flocculation in papermaking black liquor without pH neutralization. ADV POWDER TECHNOL 2021. [DOI: 10.1016/j.apt.2021.05.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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16
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Nakazawa Y, Abe T, Matsui Y, Shirasaki N, Matsushita T. Stray particles as the source of residuals in sand filtrate: Behavior of superfine powdered activated carbon particles in water treatment processes. WATER RESEARCH 2021; 190:116786. [PMID: 33387954 DOI: 10.1016/j.watres.2020.116786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 12/22/2020] [Accepted: 12/23/2020] [Indexed: 06/12/2023]
Abstract
Although superfine powdered activated carbon has excellent adsorption properties, it is not used in conventional water treatment processes comprising coagulation-flocculation, sedimentation, and sand filtration (CSF) due to concerns about its residual in treated water. Here, we examined the production and fate of very fine carbon particles with lacking in charge neutralization as a source of the residual in sand filtrate after CSF treatment. Almost all of the carbon particles in the water were charge-neutralized by coagulation treatment with rapid mixing, but a very small amount (≤0.4% of the initial concentration) of very fine carbon particles with a lesser degree of charge neutralization were left behind in coagulation process. Such carbon particles, defined as stray carbon particles, were hardly removed by subsequent flocculation and sedimentation processes, and some of them remained in the sand filtrate. The concentration of residual carbon particles in the sand filtrate varied similarly with that of the stray carbon particles. The stray and residual carbon particles were similarly smaller than the particles before coagulation treatment, but the residual carbon particles had less charge neutralization than the stray carbon particles. The turbidity of water samples collected after sedimentation was not correlated with the residual carbon concentration in the sand filtrate, even though it is often used as an indicator of treatment performance with respect to the removal of suspended matter. Based on these findings, we suggest that reduction of the amount of stray particles should be a performance goal of the CSF treatment. Examining this concept further, we confirmed that the residence time distributions in the coagulation and flocculation reactors influenced the concentration of stray carbon particles and then the residual carbon particle concentration in sand filtrate, but found that the effect was dependent on coagulant type. A multi-chambered-reactor configuration lowered both the stray carbon particle concentration after coagulation treatment and the residual carbon particle concentration in sand filtrate compared with a single-chambered reactor configuration. When a normal basicity PACl that consisted mainly of monomeric Al species was used, the stray carbon particle concentration was decreased during coagulation process and then gradually decreased during subsequent flocculation process because the monomeric Al species were transformed to colloidal Al species via polymeric Al species. In contrast, when a high-basicity PACl that consisted mostly of colloidal Al species was used, coagulation treatment largely decreased the stray carbon particle concentration, which did not decrease further during subsequent flocculation process. These findings will be valuable for controlling residual carbon particles after the CSF treatment.
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Affiliation(s)
- Yoshifumi Nakazawa
- Graduate School of Engineering, Hokkaido University, N13W8, Sapporo 060-8628, Japan
| | - Taketo Abe
- Graduate School of Engineering, Hokkaido University, N13W8, Sapporo 060-8628, Japan
| | - Yoshihiko Matsui
- Faculty of Engineering, Hokkaido University, N13W8, Sapporo 060-8628, Japan.
| | - Nobutaka Shirasaki
- Faculty of Engineering, Hokkaido University, N13W8, Sapporo 060-8628, Japan
| | - Taku Matsushita
- Faculty of Engineering, Hokkaido University, N13W8, Sapporo 060-8628, Japan
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17
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Adsorption/Coagulation/Ceramic Microfiltration for Treating Challenging Waters for Drinking Water Production. MEMBRANES 2021; 11:membranes11020091. [PMID: 33514022 PMCID: PMC7911376 DOI: 10.3390/membranes11020091] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/20/2021] [Accepted: 01/23/2021] [Indexed: 12/17/2022]
Abstract
Pressurized powdered activated carbon/coagulation/ceramic microfiltration (PAC/Alum/MF) was investigated at pilot scale for treating low turbidity and low natural organic matter (NOM) surface waters spiked with organic microcontaminants. A total of 11 trials with clarified or non-clarified waters spiked with pesticides, pharmaceutical compounds, or microcystins were conducted to assess the removal of microcontaminants, NOM (as 254 nm absorbance, A254, and dissolved organic carbon, DOC), trihalomethane formation potential (THMFP), aerobic endospores as protozoan (oo)cysts indicators, bacteriophages as viruses indicators, and regular drinking water quality parameters. PAC/(Alum)/MF achieved 75% to complete removal of total microcontaminants with 4-18 mg/L of a mesoporous PAC and 2 h contact time, with a reliable particle separation (turbidity < 0.03 NTU) and low aluminium residuals. Microcontaminants showed different amenabilities to PAC adsorption, depending on their charge, hydrophobicity (Log Kow), polar surface area and aromatic rings count. Compounds less amenable to adsorption showed higher vulnerability to NOM competition (higher A254 waters), greatly benefiting from DOC-normalized PAC dose increase. PAC/Alum/MF also attained 29-47% NOM median removal, decreasing THMFP by 26%. PAC complemented NOM removal by coagulation (+15-19%), though with no substantial improvement towards THMFP and membrane fouling. Furthermore, PAC/Alum/MF was a full barrier against aerobic endospores, and PAC dosing was crucial for ≥1.1-log reduction in bacteriophages.
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18
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Zou Z, Gu Y, Yang W, Liu M, Han J, Zhao S. A modified coagulation-ultrafiltration process for silver nanoparticles removal and membrane fouling mitigation: The role of laminarin. Int J Biol Macromol 2021; 172:241-249. [PMID: 33454322 DOI: 10.1016/j.ijbiomac.2021.01.034] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Revised: 01/04/2021] [Accepted: 01/07/2021] [Indexed: 11/25/2022]
Abstract
Silver nanoparticles (AgNPs) in surface water are highly toxic to humans and difficult to remove due to their adsorption to humic acid (HA). In this study, laminarin (LA) was used as a coagulant aid in a coagulation-ultrafiltration (C-UF) system to improve AgNPs-HA removal efficiency. C-UF efficiency, membrane flux, and flocs properties were investigated to explore the AgNPs-HA removal mechanism and membrane fouling. Results showed that when poly aluminum chloride (PAC) was dosed with LA, AgNPs-HA removal was 10-15% higher than when using PAC alone. The C-UF system using only PAC improved the AgNPs-HA removal efficiency through increased coagulation but resulted in membrane fouling. LA application helped mitigate membrane fouling, and the highest normalized permeate flux and smallest resistance values (0.573 and 2.180 × 1010 m-1, respectively) were achieved when 0.1 mg/L of LA was applied with 5 mg/L of PAC. The alleviating mechanism was related to flocs with large sizes and small fractal dimension (Df) values, generating a cake layer with porous morphology. This cake layer was easily removed by flushing and backwashing, which resulted in minimal resistance and fouling of the UF membrane.
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Affiliation(s)
- Zhangjian Zou
- School of Chemistry and Materials Science, Jiangsu Normal University, Xuzhou 221116, China
| | - Yingqiu Gu
- School of Chemistry and Materials Science, Jiangsu Normal University, Xuzhou 221116, China
| | - Weihua Yang
- School of Chemistry and Materials Science, Jiangsu Normal University, Xuzhou 221116, China
| | - Minjie Liu
- School of Chemistry and Materials Science, Jiangsu Normal University, Xuzhou 221116, China
| | - Jing Han
- School of Chemistry and Materials Science, Jiangsu Normal University, Xuzhou 221116, China
| | - Shuang Zhao
- School of Chemistry and Materials Science, Jiangsu Normal University, Xuzhou 221116, China.
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19
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Heavy Metals Removal Using Carbon Based Nanocomposites. ENVIRONMENTAL REMEDIATION THROUGH CARBON BASED NANO COMPOSITES 2021. [DOI: 10.1007/978-981-15-6699-8_12] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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20
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Qasim M, Park S, Kim JO. The role of ballast specific gravity and velocity gradient in ballasted flocculation. JOURNAL OF HAZARDOUS MATERIALS 2020; 399:122970. [PMID: 32540703 DOI: 10.1016/j.jhazmat.2020.122970] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 05/11/2020] [Accepted: 05/14/2020] [Indexed: 06/11/2023]
Abstract
This study investigated the concealed interaction between applied velocity gradient (G value) and ballast specific gravity (SG) in ballasted flocculation (BF). The objective was to unravel the participation of applied surface concentration (SC: 0.005 m2L-1-0.02 m2L-1) of high specific gravity ballasts (SG: 2.9-5.57) in BF aggregation phenomenon at varied velocity gradients (G value: 750s-1-1250s-1). Static mixer was used to perform the BF experiments, and aggregated flocs were characterized using charge coupled device (CCD) camera. The results revealed that conventionally adopted velocity gradient (G value: 150s-1 - 300s-1) in BF studies was insufficient for efficient floc development due to inadequate suspension of denser ballasts during mixing. This resulted in poor turbidity removal (< 40 %) and immature slow settling flocs (< 25 mh-1) despite higher ballast consumption. However, appropriate optimization of G value (1250s-1) corresponding to high specific gravity ballast (SG: 5.57) resulted in 99.5 % turbidity removal (residual turbidity: 1NTU) achieved in a shorter settling interval of 30 s consuming significantly less ballast concentration. This expeditious settling phenomenon was also evident in CCD camera observations of the ballasted flocs achieving superficial settling velocity (105mh-1). Therefore, it was concluded that appropriate optimization of the G value corresponding to the pertinent concentration of denser ballasts can exhibit rapid elimination of micropollutants, and superficial sedimentation with efficient material and energy use. This can lead to efficient BF design with a short HRT, compact footprint, and ability to handle highly turbid influent.
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Affiliation(s)
- Muhammad Qasim
- Department of Civil and Environmental Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 04763, Republic of Korea.
| | - Seongjun Park
- Department of Civil and Environmental Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 04763, Republic of Korea.
| | - Jong-Oh Kim
- Department of Civil and Environmental Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 04763, Republic of Korea.
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21
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Tang Y, Hu X, Cai J, Xi Z, Yang H. An enhanced coagulation using a starch-based coagulant assisted by polysilicic acid in treating simulated and real surface water. CHEMOSPHERE 2020; 259:127464. [PMID: 32593001 DOI: 10.1016/j.chemosphere.2020.127464] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 06/15/2020] [Accepted: 06/16/2020] [Indexed: 06/11/2023]
Abstract
In this work, a simple and environmentally-friendly enhanced coagulation, by using a cationic starch-based coagulant (starch-3-chloro-2-hydroxypropyl trimethyl ammonium chloride, St-CTA) coupled with an optimized polysilicic acid (PSA), has been tried to coagulate the kaolin suspensions and humic acid (HA) aqueous solutions, which are used as the simulated sources of inorganic colloidal particles and organic pollutant, respectively, in micro-polluted turbid surface water. Dosing of St-CTA and PSA at the same time is more efficient and more convenient than other two separated feeding methods in this enhanced coagulation process. The synergic coagulation process and mechanism were studied and discussed in detail based on the apparent coagulation performance, floc properties, and zeta potentials of supernatants. St-CTA caused an efficient charge neutralization, i.e. compression of electric double layer of kaolin particles and electrostatic adsorption of HA, followed by an effective netting-bridging effect of PSA, resulting in an improved purification performance. St-CTA with a higher charge density showed better purification performance due to enhanced charge neutralization effect. In addition to simulated water, the validation of this enhanced coagulation process was further confirmed by comparison with a conventional coagulant, polyaluminium chloride, in treating a real surface water. This work thus provides a simple and environmentally-friendly strategy to efficiently purify micro-polluted turbid surface water and further improve the water safety.
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Affiliation(s)
- Yunong Tang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China
| | - Xinyu Hu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China
| | - Jun Cai
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China
| | - Zhonghua Xi
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China
| | - Hu Yang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, PR China.
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22
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Conventional water treatment improvement through enhanced conventional and hybrid membrane processes to remove Ag, CuO and TiO2 nanoparticles mixture in surface waters. Sep Purif Technol 2020. [DOI: 10.1016/j.seppur.2020.117047] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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23
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Maćczak P, Kaczmarek H, Ziegler-Borowska M. Recent Achievements in Polymer Bio-Based Flocculants for Water Treatment. MATERIALS (BASEL, SWITZERLAND) 2020; 13:E3951. [PMID: 32906667 PMCID: PMC7559979 DOI: 10.3390/ma13183951] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Revised: 08/30/2020] [Accepted: 09/04/2020] [Indexed: 01/04/2023]
Abstract
Polymer flocculants are used to promote solid-liquid separation processes in potable water and wastewater treatment. Recently, bio-based flocculants have received a lot of attention due to their superior advantages over conventional synthetic polymers or inorganic agents. Among natural polymers, polysaccharides show many benefits such as biodegradability, non-toxicity, ability to undergo different chemical modifications, and wide accessibility from renewable sources. The following article provides an overview of bio-based flocculants and their potential application in water treatment, which may be an indication to look for safer alternatives compared to synthetic polymers. Based on the recent literature, a new approach in searching for biopolymer flocculants sources, flocculation mechanisms, test methods, and factors affecting this process are presented. Particular attention is paid to flocculants based on starch, cellulose, chitosan, and their derivatives because they are low-cost and ecological materials, accepted in industrial practice. New trends in water treatment technology, including biosynthetic polymers, nanobioflocculants, and stimulant-responsive flocculants are also considered.
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Affiliation(s)
- Piotr Maćczak
- Faculty of Chemistry, Nicolaus Copernicus University in Toruń, Gagarina 7, 87-100 Toruń, Poland; (P.M.); (M.Z.-B.)
- Water Supply and Sewage Enterprise LLC, Przemysłowa 4, 99-300 Kutno, Poland
| | - Halina Kaczmarek
- Faculty of Chemistry, Nicolaus Copernicus University in Toruń, Gagarina 7, 87-100 Toruń, Poland; (P.M.); (M.Z.-B.)
| | - Marta Ziegler-Borowska
- Faculty of Chemistry, Nicolaus Copernicus University in Toruń, Gagarina 7, 87-100 Toruń, Poland; (P.M.); (M.Z.-B.)
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