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Blancho F, Lapointe M, Quevedo AC, Kannan K, Tufenkji N. Demonstrating scale-up of a novel water treatment process using super-bridging agents. WATER RESEARCH 2024; 254:121301. [PMID: 38417265 DOI: 10.1016/j.watres.2024.121301] [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: 10/30/2023] [Revised: 01/22/2024] [Accepted: 02/09/2024] [Indexed: 03/01/2024]
Abstract
Fiber-based materials have emerged as a promising option to increase the efficiency of water treatment plants while reducing their environmental impacts, notably by reducing the use of unsustainable chemicals and the size of the settling tank. Cellulose fiber-based super-bridging agents are sustainable, reusable, and versatile materials that considerably improve floc separation in conventional settling tanks or via alternative screening separation methods. In this study, the effectiveness of fiber-based materials for wastewater treatment was evaluated at lab-scale (0.25 L) and at pilot-scale (20 L) for two separation methods, namely settling and screening. For the fiber-based method, the performance of floc separation during settling was slightly affected by an 80x upscaling factor. A small decrease in turbidity removal from 93 and 86 % was observed for the jar and pilot tests, respectively. By contrast, the turbidity removal of the conventional treatment, i.e., no fibers with a settling separation, was largely affected by the upscaling with turbidity removals of 84 and 49 % for jar and pilot tests, respectively. Therefore, results are suggesting that fiber-based super-bridging agents could be implemented in full-scale water treatment plants. Moreover, the tested fibers increase the robustness of treatment by providing better floc removal than conventional treatment under several challenging conditions such as low settling time and screening with coarse screen mesh size. Furthermore, at both lab-scale and pilot-scale, the use of fiber-based materials reduced the demand for coagulant and flocculant, potentially lowering the operational costs of water treatment plants and reducing the accumulation of metal-based coagulants and synthetic polymers in sludge. Acute toxicity tests using the model organism Daphnia magna show that the cellulose fibers introduce insignificant toxicity at the optimized fiber concentration. Although dedicated mechanistic studies are required at various scales to understand in detail the influence of fibers on water treatment (coagulation/flocculation time, floc formation, floc size distribution velocity gradient, etc.), the efficacy and scalability of the fiber-based approach, along with its minimal environmental impact, position it as a viable and sustainable option for existing and future wastewater treatment plants.
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Affiliation(s)
- Florent Blancho
- Department of Chemical Engineering, McGill University, Quebec H3A 0C5, Canada
| | - Mathieu Lapointe
- Department of Construction Engineering, École de technologie supérieure - University of Québec, Québec H3C 1K3, Canada.
| | - Ana C Quevedo
- Department of Chemical Engineering, McGill University, Quebec H3A 0C5, Canada
| | - Krishnaveni Kannan
- Department of Chemical Engineering, McGill University, Quebec H3A 0C5, Canada
| | - Nathalie Tufenkji
- Department of Chemical Engineering, McGill University, Quebec H3A 0C5, Canada.
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Santos Nunes G, Sammarro Silva KJ, Souza Freitas BL, Belini VL, Sabogal-Paz LP. In-situ microscopy investigation of floc development during coagulation-flocculation with chemical and natural coagulants. SEP SCI TECHNOL 2022. [DOI: 10.1080/01496395.2022.2056055] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Gustavo Santos Nunes
- Department of Hydraulic and Sanitation, São Carlos School of Engineering, University of São Paulo, São Paulo, Brazil
| | - Kamila Jessie Sammarro Silva
- Department of Hydraulic and Sanitation, São Carlos School of Engineering, University of São Paulo, São Paulo, Brazil
| | - Bárbara Luíza Souza Freitas
- Department of Hydraulic and Sanitation, São Carlos School of Engineering, University of São Paulo, São Paulo, Brazil
| | - Valdinei Luís Belini
- Department of Electrical Engineering, Universidade Federal de São Carlos, São Paulo, Brazilū
| | - Lyda Patricia Sabogal-Paz
- Department of Hydraulic and Sanitation, São Carlos School of Engineering, University of São Paulo, São Paulo, Brazil
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3
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Chen Y, Liao R, Li J, Zhou H, Wang H, Zhuo Z, Wang Q, Yan C, Ma H. Monitoring particulate composition changes during the flocculation process using polarized light scattering. APPLIED OPTICS 2021; 60:10264-10272. [PMID: 34807136 DOI: 10.1364/ao.440400] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Accepted: 10/22/2021] [Indexed: 06/13/2023]
Abstract
Monitoring the particulate composition changes during the flocculation process is still challenging for the research community. We use an experimental setup based on polarized light scattering to measure the polarization states of the scattered light of the individual particles. We build a classifier based on the support vector machine and feed it with the measured parameters. Results show that the classifier can effectively classify the particulate compositions, such as the sediment particles, flocculants, and flocs, which can be used to monitor the particulate composition changes during the flocculation process. Discussions on the intensity and polarization parameters find that the polarization parameters play a vital role in the classification of the particulate compositions in the flocculation suspensions. Additionally, the further analysis of the experimental data and the related simulations show that the degree of polarization can be an indicator of the flocculation process. We prove that the method based on polarized light scattering may be a potential in situ monitoring tool in the future for the study of the flocculation process.
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4
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Influence of molecular weight on polyacrylic acid flocculation of sub-micron titanium dioxide. Colloids Surf A Physicochem Eng Asp 2020. [DOI: 10.1016/j.colsurfa.2020.125195] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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5
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Liu D, Edraki M, Fawell P, Berry L. Improved water recovery: A review of clay-rich tailings and saline water interactions. POWDER TECHNOL 2020. [DOI: 10.1016/j.powtec.2020.01.039] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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6
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Charge Neutralization Mechanism Efficiency in Water with High Color Turbidity Ratio Using Aluminium Sulfate and Flocculation Index. WATER 2020. [DOI: 10.3390/w12020572] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Most of the water supplied in Brazil comes from water streams that may have higher values for apparent color than turbidity. Treatability trials were performed for color and turbidity removal to evaluate the advantages of coagulation during the charge neutralization mechanism when compared to sweep flocculation for water with those characteristics. There were three types of trials: conventional Jar Test with raw water, with and without filtration, and in a pilot Water Treatment Plant, direct downward filtration, with synthetic water. Auxiliary equipment such as Continuous Flocculation Monitoring Equipment (CFME) and image analysis were used to evaluate the growth of flocs. In the Jar Tests experiments, similar levels of color (61.49%) and turbidity (61.30%) removal were observed, with a lower dosage of coagulant (46 mg/L) in the charge neutralization mechanism compared to the ones with sweep flocculation (58.22% for color and 54.73% for turbidity removal with 52 mg/L of aluminium sulfate). Similar results were found on pilot plant. At filtration rates of 180 and 300 m3 m−2 day−1, sweep flocculation mechanism had shorter filtration cycle (<5 m3) compared to other mechanisms. Therefore, a change in the operation of Water Treatment plants that use a coagulant dosage associated with sweep flocculation can bring advantages such as the reduction of coagulant consumption and sludge productions, as well as the increase of chlorine disinfection and filtration cycles.
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Chao HJ, Zhang X, Wang W, Li D, Ren Y, Kang J, Liu D. Evaluation of carboxymethylpullulan-AlCl 3 as a coagulant for water treatment: A case study with kaolin. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2020; 92:302-309. [PMID: 31560145 DOI: 10.1002/wer.1250] [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: 07/27/2019] [Revised: 08/30/2019] [Accepted: 09/21/2019] [Indexed: 06/10/2023]
Abstract
A reduction in the use of aluminum (Al)-based flocculants in the treatment of drinking water is considered essential for human health reasons. In this study, a novel composite flocculant, made of carboxymethylpullulan-AlCl3 , is evaluated in a lab-scale, jar test system for the flocculation of kaolin. The results showed that the coagulation efficiency of carboxymethylpullulan-AlCl3 was more effective in reducing turbidity than the solo use of carboxymethylpullulan or AlCl3 . The optimum treatment conditions assessed by a response surface methodology were obtained at pH 6.50, 13.03 mg/L carboxymethylpullulan, and 94.87 mg/L AlCl3 . Zeta potential measurements and photometric dispersion analysis demonstrated that AlCl3 had a more significant influence on charge neutralization than carboxymethylpullulan, whilst carboxymethylpullulan facilitated absorption and the development of particle bridges. Thus, the composite flocculant possessed both advantages that enhanced flocculation, and decreased the dosage of AlCl3 , thereby reducing the potential for secondary environment pollution. When 90 mg/L carboxymethylpullulan-AlCl3 was added to the model kaolin suspension characterized by a turbidity of 50 nephelometric turbidity units, the zeta potential and the maximum flocculating activity were determined as -2.28 mV and 98.0%, respectively. The results provide insight into the development of an environment-friendly composite flocculant prepared from water-dissolved polysaccharide and inorganic flocculants. PRACTITIONER POINTS: A novel composite flocculant CMP-AlCl3 was achieved by combining CMP and AlCl3 for water treatment. The coagulation efficiency of CMP-AlCl3 was more effective in reducing turbidity than the solo use of CMP or AlCl3 . The flocculation efficiency and mechanism were investigated by Zeta potential analysis, surface morphology, electron microscopy, and coagulation.
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Affiliation(s)
- Hong-Jun Chao
- School of Biology and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan, China
| | - Xinran Zhang
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, China
| | - Wenqi Wang
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, China
| | - Daosheng Li
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, China
| | - Yongzheng Ren
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, China
| | - Jianxiong Kang
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, China
| | - Dongqi Liu
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, China
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He W, Lu W, Xu S, Huang M, Li H. Comparative analysis on floc morphological evolution in cylindrical and square stirred-tank flocculating reactors with or without baffles: Flocculation-test and CFD-aided investigations. Chem Eng Res Des 2019. [DOI: 10.1016/j.cherd.2019.05.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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9
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He W, Xie Z, Zhao Z, Huang M, Pan M. Effect of impeller clearance on floc growth behaviors in a baffled square stirred-tank reactor: Flocculation-test and CFD-aided studies. Sep Purif Technol 2019. [DOI: 10.1016/j.seppur.2018.11.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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10
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Weaver JE, Hong H, Ducoste JJ, de Los Reyes FL. Controlling aerobic biological floc size using Couette-Taylor Bioreactors. WATER RESEARCH 2018; 147:177-183. [PMID: 30308376 DOI: 10.1016/j.watres.2018.09.060] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 09/28/2018] [Accepted: 09/29/2018] [Indexed: 06/08/2023]
Abstract
Biological floc size is an important reactor microenvironment parameter that is often not experimentally controlled due to a lack of suitable methods. Here, we introduce the Couette-Taylor bioreactor (CTB) as an improved tool for controlling biological floc size, specifically as compared with bubble-column sequencing batch reactors (SBRs). A CTB consists of two concentric walls, either of which may be rotated to induce fluid motion. The induced flow produces hydrodynamic shear which is more uniform than that produced through aeration in SBRs. Because hydrodynamic shear is a major parameter controlling floc size, we hypothesized the ability to better control shear rates within a CTB would enable better-controlled floc sizes. To test this hypothesis, we measured the particle size distributions of activated sludge flocs from CTBs with either inner (iCTB) or outer (oCTB) rotating walls as well as SBRs with varying height to diameter ratios (0.5, 1.1, and 9.4). The rotation speed of the CTBs and aeration rate of the SBRs were varied to produce predicted mean shear rates from 25 to 250 s-1. Further, the shear rate distributions for each experiment were estimated using computational fluid dynamics (CFD). In all SBR experiments, the floc distributions did not significantly vary with shear rate or geometry, likely because shear rates (estimated by CFD) differed much less than originally predicted by theory. In the CTB experiments, the mean particle size decreased proportionally with increased hydrodynamic shear, and iCTBs produced particle size distributions with smaller coefficients of variation than oCTBs (0.3 vs. 0.5-0.7, respectively).
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11
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Gumfekar SP, Vajihinejad V, Soares JBP. Advanced Polymer Flocculants for Solid-Liquid Separation in Oil Sands Tailings. Macromol Rapid Commun 2018; 40:e1800644. [PMID: 30417463 DOI: 10.1002/marc.201800644] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 10/04/2018] [Indexed: 01/09/2023]
Abstract
The generation of tailings as a by product of the bitumen extraction process is one of the largest environmental footprints of oil sands operations. Most of the tailings treatment technologies use polymer flocculants to induce solid-liquid separation. However, due to the complex composition of tailings, conventional flocculants cannot reach the same performance achieved in other wastewater treatments. Over the last couple of decades, the oil sands industry has used acrylamide-based flocculants to treat tailings, achieving major progress in process optimization and integration with mechanical operations, but they still could not reach the required land reclamation targets. Over the last 5 years, the group designed, synthesized, and tested several novel polymer flocculants tailored for oil sands tailings treatment. This feature article communicates recent developments in these innovative polymers. The article first provides a background on tailings generation and treatment, followed by the description of advanced polymer flocculants categorized according to their microstructures such as linear, branched, and graft. The other tailings remediation technologies and one of the initial works on modeling of tailings flocculation is discussed.
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Affiliation(s)
- Sarang P Gumfekar
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, AB, T6G 2V4, Canada
| | - Vahid Vajihinejad
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, AB, T6G 2V4, Canada
| | - João B P Soares
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, AB, T6G 2V4, Canada
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12
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Zhu Z. A Simple Explicit Expression for the Flocculation Dynamics Modeling of Cohesive Sediment Based on Entropy Considerations. ENTROPY 2018; 20:e20110845. [PMID: 33266569 PMCID: PMC7512407 DOI: 10.3390/e20110845] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 10/25/2018] [Accepted: 11/02/2018] [Indexed: 11/24/2022]
Abstract
The flocculation of cohesive sediment plays an important role in affecting morphological changes to coastal areas, to dredging operations in navigational canals, to sediment siltation in reservoirs and lakes, and to the variation of water quality in estuarine waters. Many studies have been conducted recently to formulate a turbulence-induced flocculation model (described by a characteristic floc size with respect to flocculation time) of cohesive sediment by virtue of theoretical analysis, numerical modeling, and/or experimental observation. However, a probability study to formulate the flocculation model is still lacking in the literature. The present study, therefore, aims to derive an explicit expression for the flocculation of cohesive sediment in a turbulent fluid environment based on two common entropy theories: Shannon entropy and Tsallis entropy. This study derives an explicit expression for the characteristic floc size, assumed to be a random variable, as a function of flocculation time by maximizing the entropy function subject to the constraint equation using a hypothesis regarding the cumulative distribution function of floc size. It was found that both the Shannon entropy and the Tsallis entropy theories lead to the same expression. Furthermore, the derived expression was tested with experimental data from the literature and the results were compared with those of existing deterministic models, showing that it has good agreement with the experimental data and that it has a better prediction accuracy for the logarithmic growth pattern of data in comparison to the other models, whereas, for the sigmoid growth pattern of experimental data, the model of Keyvani and Strom or Son and Hsu model could be the better choice for floc size prediction. Finally, the maximum capacity of floc size growth, a key parameter incorporated into this expression, was found to exhibit an empirical power relationship with the flow shear rate.
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Affiliation(s)
- Zhongfan Zhu
- College of Water Sciences, Beijing Normal University, Xinjiekouwai Street 19, Beijing 100875, China
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13
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Xu J, Zhao Y, Gao B, Zhao Q. Enhanced algae removal by Ti-based coagulant: comparison with conventional Al- and Fe-based coagulants. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:13147-13158. [PMID: 29492812 DOI: 10.1007/s11356-018-1482-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Accepted: 02/04/2018] [Indexed: 06/08/2023]
Abstract
The water eutrophication caused by cyanobacteria seasonally proliferates, which is a hot potato to be resolved for water treatment plants. This study firstly investigated coagulation performance of titanium tetrachloride (TiCl4) for Microcystis aeruginosa synthetic water treatment. Results show complete algal cell removal by TiCl4 coagulation without damage to cell membrane integrity even under harsh conditions; 60 mg/L TiCl4 was effective in removing the microcystins up to 85%. Furthermore, besides having stronger UV254 removal capability and the higher removal of fluorescent substances over Al- and Fe-based coagulants, TiCl4 coagulant required more compact coagulation and sedimentation tanks due to its significantly improved floc growth and sedimentation speed. Meanwhile, its' short hydraulic retention time avoided algal cell breakage and subsequent algal organic matter release. Microcystin concentrations were kept at a low level during sludge storage period, indicating that the TiCl4 flocs could prevent algal cells from natural lysis. To facilitate water recycling without secondary contamination, the algae-containing sludge after TiCl4 coagulation ought to be disposed within 12 days at 20 °C and 8 days at 35 °C.
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Affiliation(s)
- Jie Xu
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, No. 27 Shanda South Road, Jinan, 250100, People's Republic of China
| | - Yanxia Zhao
- Key Laboratory for Special Functional Aggregated Materials of Education Ministry, School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, China.
- Environmental Engineering Research Centre, Department of Civil Engineering, The University of Hong Kong, Pokfulam, Hong Kong, SAR, China.
| | - Baoyu Gao
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, No. 27 Shanda South Road, Jinan, 250100, People's Republic of China.
| | - Qian Zhao
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, No. 27 Shanda South Road, Jinan, 250100, People's Republic of China
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14
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He W, Xue L, Gorczyca B, Nan J, Shi Z. Comparative analysis on flocculation performance in unbaffled square stirred tanks with different height-to-width ratios: Experimental and CFD investigations. Chem Eng Res Des 2018. [DOI: 10.1016/j.cherd.2018.01.055] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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15
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Experimental and CFD studies of floc growth dependence on baffle width in square stirred-tank reactors for flocculation. Sep Purif Technol 2018. [DOI: 10.1016/j.seppur.2017.08.063] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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16
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Vlieghe M, Frances C, Coufort‐Saudejaud C, Liné A. Morphological properties of flocs under turbulent break‐up and restructuring processes. AIChE J 2017. [DOI: 10.1002/aic.15745] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- M. Vlieghe
- Laboratoire de Génie ChimiqueUniversité de Toulouse, CNRS, INPT, UPSToulouse France
- LISBP, Université de Toulouse, CNRS, INRA, INSAToulouse France
| | - C. Frances
- Laboratoire de Génie ChimiqueUniversité de Toulouse, CNRS, INPT, UPSToulouse France
| | - C. Coufort‐Saudejaud
- Laboratoire de Génie ChimiqueUniversité de Toulouse, CNRS, INPT, UPSToulouse France
| | - A. Liné
- LISBP, Université de Toulouse, CNRS, INRA, INSAToulouse France
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17
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Vadasarukkai YS, Gagnon GA. Influence of the Mixing Energy Consumption Affecting Coagulation and Floc Aggregation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2017; 51:3480-3489. [PMID: 28206742 DOI: 10.1021/acs.est.6b06281] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The operational significance of energy-intensive rapid mixing processes remains unaddressed in coagulation and flocculation of insoluble precipitates (flocs), which play an important role in the removal of impurities from drinking water supplies. In this study, the influence of rapid mixing and associated mixing energy on floc aggregation was examined for a surface water source characterized by a high fraction of aquatic humic matter. Infrared spectral analyses showed that the colloidal complexes resulting from ligand exchange between iron and dissolved natural organic matter (DOM) were not substantially influenced by the mixing energy input. This signified that DOM removal by coagulation can be achieved at lower mixing intensity, thereby reducing energy consumption. In contrast, macroscopic investigations showed the coagulation mixing energy affected floc size distributions during the slow mixing stage in flocculation and, to some extent, their settling characteristics. The results from analysis of floc properties clearly showed that more mixing energy was expended than necessary in coagulation, which is typically designed at a high mixing intensity range of 600-1000 s-1 in treatment plants. The key findings from this study have practical implications to water utilities to strategically meet water quality goals while reducing energy demands.
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Zhao Y, Phuntsho S, Gao B, Shon H. Polytitanium sulfate (PTS): Coagulation application and Ti species detection. J Environ Sci (China) 2017; 52:250-258. [PMID: 28254045 DOI: 10.1016/j.jes.2016.04.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 04/01/2016] [Accepted: 04/20/2016] [Indexed: 06/06/2023]
Abstract
Interest in the development of inorganic polymerized coagulants is growing; however, there are only limited studies on the synthesis of polytitanium coagulants, which are expected to exhibit improved coagulation efficiency with better floc properties. This study presents the synthesis of polytitanium sulfate (PTS) for potential application in water purification, followed by characterization of PTS flocs and titanium species detection. Stable PTS solutions were successfully synthesized and standard jar tests were conducted to evaluate their coagulation efficiency. Electrospray ionization time-of-flight mass spectrometry (ESI-TOF-MS) speciation analysis revealed that a variety of mononuclear and polynuclear complexes were formed in PTS solution, indicating the polymeric nature of the synthesized coagulant. Floc characteristics were studied through on-line monitoring of floc size using a laser diffraction particle size analyzer. Results showed that PTS had a comparable or in some cases even higher organic matter and particulate removal efficiency than Ti(SO4)2. The effluent pH after PTS coagulation significantly improved toward desirable values closer to neutral pH. Properties of flocs formed by PTS were significantly improved in terms of floc size, growth rate and structure. This study showed that PTS could be an efficient and promising coagulant for water purification, with the additional benefit that its coagulated sludge can be used to recover valuable TiO2 nanoparticles for various commercial applications.
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Affiliation(s)
- Yanxia Zhao
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100, China; Key Laboratory for Special Functional Aggregated Materials of Education Ministry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China
| | - Sherub Phuntsho
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology, Sydney, Broadway, NSW 2007, Australia
| | - Baoyu Gao
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100, China.
| | - Hokyong Shon
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology, Sydney, Broadway, NSW 2007, Australia.
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Zhao Y, Sun Y, Tian C, Gao B, Wang Y, Shon H, Yang Y. Titanium tetrachloride for silver nanoparticle-humic acid composite contaminant removal in coagulation-ultrafiltration hybrid process: floc property and membrane fouling. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:1757-1768. [PMID: 27796984 DOI: 10.1007/s11356-016-7813-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Accepted: 09/29/2016] [Indexed: 06/06/2023]
Abstract
Titanium-based coagulation is expected to achieve both efficient water purification and sludge recycling. This study is the first attempt to use titanium tetrachloride (TiCl4) for silver nanoparticle (AgNP)-humic acid composite contaminant removal in a coagulation-ultrafiltration (C-UF) process, where characterization of flocs and membrane fouling under varied coagulant dose, initial solution pH, and AgNP concentration conditions are the main contents. Results suggested that the TiCl4 achieved high AgNP removal in the form of silver nanoparticle through adsorption and sweep flocculation and simultaneously exerted additional 68.2 % higher dissolved organic carbon removal than Al2(SO4)3. The TiCl4 produced larger and stronger flocs but with weaker recoverability and less compact degree than did Al2(SO4)3. Floc properties were independent of AgNP concentration except floc fractal dimension, which was negatively correlated with AgNP concentration. The TiCl4 precoagulation caused less membrane fouling within wider pH range than Al2(SO4)3 did in the C-UF process. Incorporation of AgNPs during the TiCl4 pretreatment process facilitated the mitigation of membrane fouling, which was, however, negligibly influenced by AgNP concentration in the case of Al2(SO4)3.
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Affiliation(s)
- Yanxia Zhao
- Department of Civil Engineering, Faculty of Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
- Key Laboratory for Special Functional Aggregated Materials of Education Ministry, School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, China
| | - Yangyang Sun
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, No.27 Shanda South Road, Jinan, 250100, People's Republic of China
| | - Chang Tian
- School of Environmental Science and Engineering, Qilu University of Technology, Jinan, 250353, China
| | - Baoyu Gao
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, No.27 Shanda South Road, Jinan, 250100, People's Republic of China
| | - Yan Wang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, No.27 Shanda South Road, Jinan, 250100, People's Republic of China.
| | - Hokyong Shon
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology, (UTS), P.O. Box 123, Broadway, Sydney, NSW, 2007, Australia
| | - Yanzhao Yang
- Key Laboratory for Special Functional Aggregated Materials of Education Ministry, School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, China
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Zhu Z, Wang H, Yu J, Dou J. On the Kaolinite Floc Size at the Steady State of Flocculation in a Turbulent Flow. PLoS One 2016; 11:e0148895. [PMID: 26901652 PMCID: PMC4763281 DOI: 10.1371/journal.pone.0148895] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Accepted: 01/24/2016] [Indexed: 11/18/2022] Open
Abstract
The flocculation of cohesive fine-grained sediment plays an important role in the transport characteristics of pollutants and nutrients absorbed on the surface of sediment in estuarine and coastal waters through the complex processes of sediment transport, deposition, resuspension and consolidation. Many laboratory experiments have been carried out to investigate the influence of different flow shear conditions on the floc size at the steady state of flocculation in the shear flow. Most of these experiments reported that the floc size decreases with increasing shear stresses and used a power law to express this dependence. In this study, we performed a Couette-flow experiment to measure the size of the kaolinite floc through sampling observation and an image analysis system at the steady state of flocculation under six flow shear conditions. The results show that the negative correlation of the floc size on the flow shear occurs only at high shear conditions, whereas at low shear conditions, the floc size increases with increasing turbulent shear stresses regardless of electrolyte conditions. Increasing electrolyte conditions and the initial particle concentration could lead to a larger steady-state floc size.
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Affiliation(s)
- Zhongfan Zhu
- College of Water Sciences, Beijing Normal University, Beijing, China
| | - Hongrui Wang
- College of Water Sciences, Beijing Normal University, Beijing, China
| | - Jingshan Yu
- College of Water Sciences, Beijing Normal University, Beijing, China
- * E-mail:
| | - Jie Dou
- Department of Natural Environmental Studies, The University of Tokyo, Kashiwa, Japan
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21
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Nan J, Yao M, Chen T, Wang Z, Li Q, Zhan D. Experimental and numerical characterization of floc morphology: role of changing hydraulic retention time under flocculation mechanisms. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2016; 23:3596-3608. [PMID: 26490940 DOI: 10.1007/s11356-015-5539-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 10/05/2015] [Indexed: 06/05/2023]
Abstract
The formation, breakage, and re-growth of flocs were investigated by using modified flocculation tests and numerical simulation to explore the evolution of floc morphology for different hydraulic retention times. The shorter the aggregation time was, the smaller the flocs produced for the same hydraulic conditions were. Another interesting discovery was that broken flocs that formed in shorter aggregation time had the capacity to completely recover, whereas those formed in a longer amount of time had rather worse reversibility of broken flocs. With the addition of the maximum motion step in the representative two-dimensional diffusion-limited aggregation (DLA) model, there was a transition for flocs from isotropic to anisotropic as the maximum motion step increased. The strength of flocs was mainly affected by the distribution of particles near the aggregated core rather than distant particles. A simplified breakage model, which found that broken flocs provided more chances for diffused particles to access the inner parts of flocs and to be uniformly packed around the aggregated core, was first proposed. Moreover, an important result showed that the floc fragments formed with a larger value of the maximum motion step had more growing sites than did those with a smaller msa value, which was a benefit of following the re-forming procedure.
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Affiliation(s)
- Jun Nan
- Skate Key Laboratory of Urban Water Resource and Environment, School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin, 150090, People's Republic of China.
| | - Meng Yao
- Skate Key Laboratory of Urban Water Resource and Environment, School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin, 150090, People's Republic of China
| | - Ting Chen
- Skate Key Laboratory of Urban Water Resource and Environment, School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin, 150090, People's Republic of China
| | - Zhenbei Wang
- Skate Key Laboratory of Urban Water Resource and Environment, School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin, 150090, People's Republic of China
| | - Qinggui Li
- Skate Key Laboratory of Urban Water Resource and Environment, School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin, 150090, People's Republic of China
| | - Dan Zhan
- Skate Key Laboratory of Urban Water Resource and Environment, School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin, 150090, People's Republic of China
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22
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Sun S, Weber-Shirk M, Lion LW. Characterization of Flocs and Floc Size Distributions Using Image Analysis. ENVIRONMENTAL ENGINEERING SCIENCE 2016; 33:25-34. [PMID: 26909006 PMCID: PMC4752185 DOI: 10.1089/ees.2015.0311] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 10/15/2015] [Indexed: 06/05/2023]
Abstract
A nonintrusive digital imaging process was developed to study particle size distributions created through flocculation and sedimentation. Quantification of particle size distributions under different operating conditions can be of use in the understanding of aggregation mechanisms. This process was calibrated by measuring standardized polystyrene particles of known size and was utilized to count and measure individual kaolin clay particles as well as aggregates formed by coagulation with polyaluminum chloride and flocculation. Identification of out-of-focus flocs was automated with LabVIEW and used to remove them from the database that was analyzed. The particle diameter of the test suspension of kaolinite clay was measured to be 7.7 ± 3.8 μm and a linear relationship was obtained between turbidity and the concentration of clay particles determined by imaging. The analysis technique was applied to characterize flocs and floc particle size distribution as a function of coagulant dose. Removal of flocs by sedimentation was characterized by imaging, and the negative logarithm of the fraction of turbidity remaining after settling had a linear relationship with the logarithm of aluminum dose. The maximum floc size observed in the settled water was less than 120 μm, which was in accordance with the value predicted by a model for the capture velocity of the experimental tube settler of 0.21 mm/s.
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Affiliation(s)
- Siwei Sun
- School of Civil and Environmental Engineering, Cornell
University, Ithaca, New York
| | - Monroe Weber-Shirk
- School of Civil and Environmental Engineering, Cornell
University, Ithaca, New York
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23
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State of the Art of Online Monitoring and Control of the Coagulation Process. WATER 2015. [DOI: 10.3390/w7116574] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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24
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Fractal Dimension of Cohesive Sediment Flocs at Steady State under Seven Shear Flow Conditions. WATER 2015. [DOI: 10.3390/w7084385] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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25
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Li R, Gao B, Sun S, Wang H, Liu Y, Yue Q, Wang Y. Coagulation behavior and floc structure characteristics of cationic lignin-based polymer-polyferric chloride dual-coagulants under different coagulation conditions. RSC Adv 2015. [DOI: 10.1039/c5ra22637f] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
To recycle papermaking sludge, a novel lignin-based flocculant with high cationic degree and molecular weight was introduced.
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Affiliation(s)
- Ruihua Li
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse
- School of Environmental Science and Engineering
- Shandong University
- Jinan 250100
- People's Republic of China
| | - Baoyu Gao
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse
- School of Environmental Science and Engineering
- Shandong University
- Jinan 250100
- People's Republic of China
| | - Shenglei Sun
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse
- School of Environmental Science and Engineering
- Shandong University
- Jinan 250100
- People's Republic of China
| | - Hui Wang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse
- School of Environmental Science and Engineering
- Shandong University
- Jinan 250100
- People's Republic of China
| | - Yingxue Liu
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse
- School of Environmental Science and Engineering
- Shandong University
- Jinan 250100
- People's Republic of China
| | - Qinyan Yue
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse
- School of Environmental Science and Engineering
- Shandong University
- Jinan 250100
- People's Republic of China
| | - Yan Wang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse
- School of Environmental Science and Engineering
- Shandong University
- Jinan 250100
- People's Republic of China
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26
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Zhao YX, Phuntsho S, Gao BY, Yang YZ, Kim JH, Shon HK. Comparison of a novel polytitanium chloride coagulant with polyaluminium chloride: coagulation performance and floc characteristics. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2015; 147:194-202. [PMID: 25291677 DOI: 10.1016/j.jenvman.2014.09.023] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2014] [Revised: 08/24/2014] [Accepted: 09/14/2014] [Indexed: 06/03/2023]
Abstract
Polymerized inorganic coagulants are increasingly being used in the water supply and wastewater treatment process, yet there is limited research on the development of polytitanium coagulants. The aim of this study is to synthesize polytitanium chloride (PTC) coagulants and investigate their coagulation behavior and floc characteristics for humic acid removal in comparison to polyaluminum chloride (PAC). The PTC samples with different B (molar ratios of OH/Ti) values were prepared using an instantaneous base-feeding method, employing sodium carbonate as the basification agent. The coagulation efficiency was significantly influenced by different B values. The results suggest that the humic acid removal increased with the increasing B value for PAC, while the inverse trend was observed for PTC. The optimum B value was chosen at 1.0 and 2.0 for PTC and PAC, respectively. Under the optimum coagulant dose and initial solution pH conditions, the PTC coagulant performed better than the PAC coagulant and the floc properties were significantly improved in terms of floc growth rate and floc size. However, the PAC coagulants produced flocs with better floc recoverability than the PTC coagulants.
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Affiliation(s)
- Y X Zhao
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, No. 27 Shanda South Road, Jinan 250100, China
| | - S Phuntsho
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology, Sydney (UTS), P.O. Box 123, Broadway, NSW 2007, Australia
| | - B Y Gao
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, No. 27 Shanda South Road, Jinan 250100, China.
| | - Y Z Yang
- Key Laboratory for Special Functional Aggregated Materials of Education Ministry, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China
| | - J-H Kim
- School of Applied Chemical Engineering & The Institute for Catalysis Research, Chonnam National University, Gwangju 500-757, South Korea
| | - H K Shon
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology, Sydney (UTS), P.O. Box 123, Broadway, NSW 2007, Australia.
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27
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Sun C, Zhao Y, Zhang Z, Zhang Y, Zhang X. Decolorization of dyeing wastewater and characterization of flocs during coagulation by a new composite coagulant. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2015; 72:187-193. [PMID: 26177400 DOI: 10.2166/wst.2015.191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A composite coagulant, polymeric aluminum ferric chloride-poly-epichlorohydrin-ethylenediamine (PAFC-EPI-ETA), was synthesized and then used for the treatment of synthetic reactive brilliant red (RBR) dyeing wastewater. Effects of (Fe+Al) to EPI-ETA mass ratio (P) on the color removal and zeta potential were investigated under different coagulant dosages and initial pHs. Experimental results indicate that the removal of reactive dye and the charge neutralization ability of composite coagulant were improved by increasing the content of organic EPI-ETA. PAFC-EPI-ETA with P=1 achieved the best color removal percentage and strongest charge neutralization ability. Decolorization efficiency using PAFC-EPI-ETA was quite effecient with pH range of 6.0-7.5 for RBR dye removal. Characteristics of the formed floc were investigated with the dosage of PAFC-EPI-ETA under different P values. The low (Fe+Al) to EPI-ETA mass ratio contributed to the formation of flocs with high growth rate, large size and large size variation.
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Affiliation(s)
- Cuizhen Sun
- School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan 250101, China E-mail: ;
| | - Yang Zhao
- School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan 250101, China E-mail: ;
| | - Zhibin Zhang
- School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan 250101, China E-mail: ; ; Center for Sustainable Development and Global Competitiveness, Stanford University, Stanford, CA 94305, USA
| | - Yanhao Zhang
- School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan 250101, China E-mail: ;
| | - Xiaorui Zhang
- School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan 250101, China E-mail: ;
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28
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Li R, Gao B, Huang X, Dong H, Li X, Yue Q, Wang Y, Li Q. Compound bioflocculant and polyaluminum chloride in kaolin-humic acid coagulation: factors influencing coagulation performance and floc characteristics. BIORESOURCE TECHNOLOGY 2014; 172:8-15. [PMID: 25218625 DOI: 10.1016/j.biortech.2014.08.126] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 08/28/2014] [Accepted: 08/31/2014] [Indexed: 06/03/2023]
Abstract
The objective of this study was to investigate the influence of coagulant dosage and pH on coagulation performance and floc properties using polyaluminum chloride (PAC) and compound bioflocculant (CBF) dual-coagulant in kaolin-humic acid (HA) treatment. Results showed that as PAC dosage rose, comparatively better coagulation efficiencies and floc characteristics were achieved due to stronger charge neutralization and sweeping effect. Addition of CBF could enhance coagulation performance and floc properties, including size, strength and recoverability, except fractal dimension. Solution pH had a significant effect on coagulation efficiencies and flocs formation. Under acidic condition, flocs showed higher strength and recoverability but lower fractal dimension, where charge neutralization was the foremost mechanism. More compact flocs were generated under alkaline condition due to the sweeping effect of hydrolyzed Al species.
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Affiliation(s)
- Ruihua Li
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, No. 27 Shanda South Road, Jinan 250100, Shandong, People's Republic of China
| | - Baoyu Gao
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, No. 27 Shanda South Road, Jinan 250100, Shandong, People's Republic of China.
| | - Xin Huang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, No. 27 Shanda South Road, Jinan 250100, Shandong, People's Republic of China
| | - Hongyu Dong
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, No. 27 Shanda South Road, Jinan 250100, Shandong, People's Republic of China
| | - Xiaochen Li
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, No. 27 Shanda South Road, Jinan 250100, Shandong, People's Republic of China
| | - Qinyan Yue
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, No. 27 Shanda South Road, Jinan 250100, Shandong, People's Republic of China
| | - Yan Wang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, No. 27 Shanda South Road, Jinan 250100, Shandong, People's Republic of China
| | - Qian Li
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, No. 27 Shanda South Road, Jinan 250100, Shandong, People's Republic of China
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29
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Zhao S, Gao B, Yue Q, Wang Y, Li Q, Dong H, Yan H. Study of Enteromorpha polysaccharides as a new-style coagulant aid in dye wastewater treatment. Carbohydr Polym 2014; 103:179-86. [DOI: 10.1016/j.carbpol.2013.12.045] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2013] [Revised: 12/02/2013] [Accepted: 12/13/2013] [Indexed: 11/28/2022]
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30
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Braun K, Cruaux L, Fabris R, Morran J, Ho L, Drikas M. Comparison of coagulation and MIEX pre-treatment processes for bacterial and turbidity removal, utilizing real-time optical monitoring techniques. ENVIRONMENTAL TECHNOLOGY 2014; 35:1038-1045. [PMID: 24645488 DOI: 10.1080/09593330.2013.859737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Jar testing and flow cytometry were used in conjunction with photometric dispersion analysis (PDA) to assess conventional alum coagulation with and without magnetic ion exchange (MIEX) pre-treatment for turbidity and bacterial removal capacity. Treatment assessment included powdered activated carbon (PAC) and pre-chlorination of the MIEX-treated raw water. Floc particles were subjected to shear forces after settling and re-suspended to gauge bacterial release potential, floc breakage and re-aggregation. MIEX in conjunction with alum coagulation achieved improved coagulation as measured by PDA but did not increase bacterial log removal value (LRV) in comparison with conventional coagulation. Pre-chlorination and PAC addition were seen to improve bacterial removal and coagulation, respectively, but were less effective for bacterial LRVs when they were used in conjunction during coagulation.
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31
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Zhao YX, Shon HK, Phuntsho S, Gao BY. Removal of natural organic matter by titanium tetrachloride: The effect of total hardness and ionic strength. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2014; 134:20-29. [PMID: 24463732 DOI: 10.1016/j.jenvman.2014.01.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Revised: 12/26/2013] [Accepted: 01/02/2014] [Indexed: 06/03/2023]
Abstract
This study is the first attempt to investigate the effect of total hardness and ionic strength on coagulation performance and the floc characteristics of titanium tetrachloride (TiCl4). Membrane fouling under different total hardness and ionic strength conditions was also evaluated during a coagulation-ultrafiltration (C-UF) hybrid process. Coagulation experiments were performed with two simulated waters, using humic acid (HA, high molecular weight) and fulvic acid (FA, relatively low molecular weight), respectively, as model natural organic matter (NOM). Results show that both particle and organic matter removal can be enhanced by increasing total hardness and ionic strength. Floc characteristics were significantly influenced by total hardness and ionic strength and were improved in terms of floc size, growth rate, strength, recoverability and compactness. The results of the UF tests show that the pre-coagulation with TiCl4 significantly improves the membrane permeate fluxes. Under different total hardness and ionic strength conditions, the membrane permeate flux varied according to both NOM and floc characteristics. The increase in total hardness and ionic strength improved the membrane permeate flux in the case of HA simulated water treatment.
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Affiliation(s)
- Y X Zhao
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, No. 27 Shanda South Road, Jinan 250100, People's Republic of China
| | - H K Shon
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology, Sydney (UTS), P.O. Box 123, Broadway, NSW 2007, Australia
| | - S Phuntsho
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology, Sydney (UTS), P.O. Box 123, Broadway, NSW 2007, Australia
| | - B Y Gao
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, No. 27 Shanda South Road, Jinan 250100, People's Republic of China.
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32
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Zhou Z, Yang Y, Li X, Wang W, Wu Y, Wang C, Luo J. Coagulation performance and flocs characteristics of recycling pre-sonicated condensate sludge for low-turbidity surface water treatment. Sep Purif Technol 2014. [DOI: 10.1016/j.seppur.2013.12.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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33
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Stack K, Lee R, Richardson D, Lewis T, Garnier G. Complex formation and stability of colloidal wood resin pitch suspensions with hemicellulose polymers. Colloids Surf A Physicochem Eng Asp 2014. [DOI: 10.1016/j.colsurfa.2013.08.057] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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34
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Zhao YX, Phuntsho S, Gao BY, Huang X, Qi QB, Yue QY, Wang Y, Kim JH, Shon HK. Preparation and characterization of novel polytitanium tetrachloride coagulant for water purification. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:12966-12975. [PMID: 24106890 DOI: 10.1021/es402708v] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Polymeric metal coagulants are increasingly being used to improve coagulation efficiency, yet the research on the development of titanium and particularly polytitanium salts remains limited. This study is the first attempt in the synthesis, characterization, and application of polytitanium salts as coagulants. Polytitanium tetrachloride (PTC) solutions with different basicity values B (OH/Ti molar ratio) were prepared using a slow alkaline titration method. Jar tests were conducted to assess coagulation performance using both synthetic and real raw water samples, and the floc characteristics were monitored online using a laser diffraction particle size analyzer. Electrospray ionization time-of-flight mass spectrometry (ESI-TOF-MS) was utilized to identify various Ti species, with the results providing strong evidence of the presence of various hydrolyzed Ti species in the titanium aqueous phase. Compared to titanium tetrachloride (TiCl4), higher or comparable turbidity and organic matter removal efficiency could be achieved by PTC with improved floc characteristics in terms of size, growth rate, and structure. Besides, the water pH after PTC coagulation was significantly improved toward neutral pH. This study indicates that PTC is an effective and promising coagulant for water purification. Besides, the PTC flocculated sludge was able to recycle and produce functional TiO2 photocatalyst.
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Affiliation(s)
- Y X Zhao
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University , No.27 Shanda South Road, Jinan, 250100, People's Republic of China
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35
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Yang Z, Liu X, Gao B, Zhao S, Wang Y, Yue Q, Li Q. Flocculation kinetics and floc characteristics of dye wastewater by polyferric chloride–poly-epichlorohydrin–dimethylamine composite flocculant. Sep Purif Technol 2013. [DOI: 10.1016/j.seppur.2013.08.004] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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36
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Abstract
In current paper, ballasted flocculation as a simulated Actiflo and Sirofloc process with coagulant, micro-sand (MS)/magnetic powder (MP) and PAM was optimized using single-factor and orthogonal experimental method for eutrophic landscape water treatment. A flocculation index instrument was also used to indicate the flocs property. It was determined that the optimum removal rate of turbidity, UV254, CODMnand total phosphorus, with 96.11%, 34.63%, 57.88% and 55.32%, respectively were achieved under MP ballasted flocculation with PAM added 2 minutes after initial mixing. Additionally, MS/MP ballasted flocculation with or without PAM could not significantly increase the velocity of flocs formation, but the flocs size could be increased observably by MP ballasted flocculation regardless of PAM.
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37
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Zhao YX, Gao BY, Qi QB, Wang Y, Phuntsho S, Kim JH, Yue QY, Li Q, Shon HK. Cationic polyacrylamide as coagulant aid with titanium tetrachloride for low molecule organic matter removal. JOURNAL OF HAZARDOUS MATERIALS 2013; 258-259:84-92. [PMID: 23708450 DOI: 10.1016/j.jhazmat.2013.04.044] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Revised: 04/11/2013] [Accepted: 04/28/2013] [Indexed: 06/02/2023]
Abstract
This is the first attempt to use cationic polyacrylamide (PAM) as coagulant aid with titanium tetrachloride (TiCl4) to improve the coagulation performance and floc properties. Coagulation-flocculation treatment was applied to simulated water (with fulvic acid (FA) as model organic matter) for both coagulation behavior investigation and floc characterization. The effect of PAM on floc reformation properties after cyclic breakage/regrowth was also investigated. Ultrafiltration experiments were performed to investigate the influence of PAM aided TiCl4 coagulation on the membrane fouling. The results showed that organic removal was enhanced by PAM addition at low TiCl4 doses. Floc growth rate and floc size were significantly affected by dosing sequence. TiCl4-PAM significantly improved the floc strength factors (Sf) and recovery factors (Rf). The dosing sequence of TiCl4 and PAM significantly influenced the floc structure. Characterization of the flocculated sludge indicated that TiO2 with anatase structure and high photocatalytic activity could be obtained from the TiCl4-PAM flocculated sludge.
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Affiliation(s)
- Y X Zhao
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan, People's Republic of China
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38
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Bubakova P, Pivokonsky M, Filip P. Effect of shear rate on aggregate size and structure in the process of aggregation and at steady state. POWDER TECHNOL 2013. [DOI: 10.1016/j.powtec.2012.11.014] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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39
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Xu W, Gao B. Effect of shear conditions on floc properties and membrane fouling in coagulation/ultrafiltration hybrid process—The significance of Alb species. J Memb Sci 2012. [DOI: 10.1016/j.memsci.2012.04.046] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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40
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41
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Moussas P, Zouboulis A. Synthesis, characterization and coagulation behavior of a composite coagulation reagent by the combination of polyferric sulfate (PFS) and cationic polyelectrolyte. Sep Purif Technol 2012. [DOI: 10.1016/j.seppur.2012.06.024] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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42
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Ho L, Braun K, Fabris R, Hoefel D, Morran J, Monis P, Drikas M. Comparison of drinking water treatment process streams for optimal bacteriological water quality. WATER RESEARCH 2012; 46:3934-3942. [PMID: 22608607 DOI: 10.1016/j.watres.2012.04.041] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Revised: 04/23/2012] [Accepted: 04/25/2012] [Indexed: 06/01/2023]
Abstract
Four pilot-scale treatment process streams (Stream 1 - Conventional treatment (coagulation/flocculation/dual media filtration); Stream 2 - Magnetic ion exchange (MIEX)/Conventional treatment; Stream 3 - MIEX/Conventional treatment/granular activated carbon (GAC) filtration; Stream 4 - Microfiltration/nanofiltration) were commissioned to compare their effectiveness in producing high quality potable water prior to disinfection. Despite receiving highly variable source water quality throughout the investigation, each stream consistently reduced colour and turbidity to below Australian Drinking Water Guideline levels, with the exception of Stream 1 which was difficult to manage due to the reactive nature of coagulation control. Of particular interest was the bacteriological quality of the treated waters where flow cytometry was shown to be the superior monitoring tool in comparison to the traditional heterotrophic plate count method. Based on removal of total and active bacteria, the treatment process streams were ranked in the order: Stream 4 (average log removal of 2.7) > Stream 2 (average log removal of 2.3) > Stream 3 (average log removal of 1.5) > Stream 1 (average log removal of 1.0). The lower removals in Stream 3 were attributed to bacteria detaching from the GAC filter. Bacterial community analysis revealed that the treatments affected the bacteria present, with the communities in streams incorporating conventional treatment clustering with each other, while the community composition of Stream 4 was very different to those of Streams 1, 2 and 3. MIEX treatment was shown to enhance removal of bacteria due to more efficient flocculation which was validated through the novel application of the photometric dispersion analyser.
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Affiliation(s)
- Lionel Ho
- Australian Water Quality Centre, SA Water Corporation, 250 Victoria Square, Adelaide, SA 5000, Australia.
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43
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Coagulation performance and floc characteristics of aluminum sulfate using sodium alginate as coagulant aid for synthetic dying wastewater treatment. Sep Purif Technol 2012. [DOI: 10.1016/j.seppur.2012.05.009] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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44
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Zhao YX, Gao BY, Shon HK, Wang Y, Kim JH, Yue QY, Bo XW. Anionic polymer compound bioflocculant as a coagulant aid with aluminum sulfate and titanium tetrachloride. BIORESOURCE TECHNOLOGY 2012; 108:45-54. [PMID: 22284758 DOI: 10.1016/j.biortech.2012.01.012] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2011] [Revised: 01/04/2012] [Accepted: 01/04/2012] [Indexed: 05/31/2023]
Abstract
The objectives of this study are to investigate the impacts of anionic polymer compound bioflocculant (CBF) as a coagulant aid on coagulation performance and floc characteristics with titanium tetrachloride (TiCl(4)) and aluminum sulfate (Al(2)(SO(4))(3)). The effect of dosing sequence was also investigated. Floc size, breakage, regrowth and floc fractal dimension were examined using a laser diffraction instrument. The results showed that CBF with TiCl(4) or Al(2)(SO(4))(3) coagulants exhibited synergistic effects by promoting dissolved organic carbon (DOC) removal. For both TiCl(4) and Al(2)(SO(4))(3), the floc recoverability was improved by CBF addition, and the flocs formed by TiCl(4) and the corresponding dual-coagulants showed weaker recovery ability than those by Al(2)(SO(4))(3) and the corresponding dual-coagulants. Fractal dimension analysis demonstrated that the floc fractal dimension values increased with the increasing coagulant dose. The effect of CBF on fractal dimension of the flocs generated by TiCl(4) was different from that of Al(2)(SO(4))(3).
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Affiliation(s)
- Y X Zhao
- School of Environmental Science and Engineering, Shandong University, No. 27 Shanda South Road, Jinan 250100, Shandong, People's Republic of China
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45
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Lee R, Stack K, Richardson D, Lewis T, Garnier G. Effect of shear, temperature and pH on the dynamics of salt induced coagulation of wood resin colloids. Colloids Surf A Physicochem Eng Asp 2012. [DOI: 10.1016/j.colsurfa.2011.12.049] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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46
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Zhao YX, Gao BY, Shon HK, Wang Y, Kim JH, Yue QY. The effect of second coagulant dose on the regrowth of flocs formed by charge neutralization and sweep coagulation using titanium tetrachloride (TiCl4). JOURNAL OF HAZARDOUS MATERIALS 2011; 198:70-77. [PMID: 22030273 DOI: 10.1016/j.jhazmat.2011.10.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Revised: 10/03/2011] [Accepted: 10/03/2011] [Indexed: 05/31/2023]
Abstract
Characteristics of flocs formed by charge neutralization and sweep coagulation using titanium tetrachloride (TiCl(4)) were investigated with humic acid-kaolin suspension by continuous optical monitoring. This paper focused on the regrowth ability of broken flocs after addition of second TiCl(4) dose. Variation of floc size and the fractal dimension of flocs versus second TiCl(4) dose after regrowth were investigated. Second TiCl(4) dose was added during the floc breakage period, and addition time of second TiCl(4) dose was also investigated. The results showed that, when coagulated by charge neutralization at pH 6, an appropriate second TiCl(4) dose improved regrowth ability of broken flocs at low initial TiCl(4) doses. While for high initial TiCl(4) doses, second TiCl(4) dose lowered floc re-growth ability. When coagulated by sweep coagulation at pH 10, second TiCl(4) dose made regrown flocs larger than those without second TiCl(4) dose. Floc structure analysis showed that it was determined by not only the fractal dimension of flocs, but also the chemical characteristics of floc surface. Addition time of second TiCl(4) dose had a great effect on floc regrowth ability, suggesting that the broken flocs had better regrowth when second TiCl(4) dose was added at the end of the breakage period.
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Affiliation(s)
- Y X Zhao
- School of Environmental Science and Engineering, Shandong University, Jinan, Shandong, People's Republic of China
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47
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Pitch deposition at the solid–liquid interface: Effect of surface hydrophobicity/hydrophilicity and cation specificity. Colloids Surf A Physicochem Eng Asp 2011. [DOI: 10.1016/j.colsurfa.2011.08.019] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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48
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Ball T, Carrière A, Barbeau B. Comparison of two online flocculation monitoring techniques for predicting turbidity removal by granular media filtration. ENVIRONMENTAL TECHNOLOGY 2011; 32:1095-1105. [PMID: 21882562 DOI: 10.1080/09593330.2010.528041] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Particulate matter removal in drinking water treatment via direct granular filtration requires specific flocculation conditions (a process typically termed 'high energy flocculation'). Predicting filtered water turbidity based on flocculated water characteristics remains difficult. This study has sought to establish a relationship between filtered water turbidity and the flocculated water characteristics. Flocculation oflow-turbidity raw water was evaluated online using a Photometric Dispersion Analyser (PDA) and a Dynamic Particle Analyser in a modified jar test followed by a bench-scale anthracite filter. Coagulants used were alum, PASS100 and ferric sulphate, in addition to a polydiallyldimethylammonium chloride (polyDADMAC) cationic polymer. They were dosed in warm and cold waters, and flocculated with intensities (G) from 0 to 100 s(-1). Of the two instruments selected to analyse flocculation performance, the Dynamic Particle Analyser was shown to be the most sensitive, detecting small changes in floc growth kinetics and even floc growth under low flocculation conditions which remained undetected by the PDA. Floc size was shown to be insufficient in predicting particulate matter removal by direct granular filtration as measured by turbidity, although a threshold d(v) value (50 microm) could be identified for the test conditions evaluated in this project, above which turbidity was systematically lower than 0.2 NTU.
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Affiliation(s)
- T Ball
- NSERC Industrial Chair in Drinking Water, Department of Civil, Geological and Mining Engineering, Ecole Polytechnique de Montréal, Montreal, Canada
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49
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Gao B, Liu B, Chen T, Yue Q. Effect of aging period on the characteristics and coagulation behavior of polyferric chloride and polyferric chloride-polyamine composite coagulant for synthetic dying wastewater treatment. JOURNAL OF HAZARDOUS MATERIALS 2011; 187:413-420. [PMID: 21295910 DOI: 10.1016/j.jhazmat.2011.01.044] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2010] [Revised: 12/10/2010] [Accepted: 01/12/2011] [Indexed: 05/30/2023]
Abstract
In this paper, a new composite inorganic-organic coagulant (PFC-EPI-DMA) was prepared by polyferric chloride (PFC) and epichlorohydrin-dimethylamine (EPI-DMA) under a given EPI-DMA/Fe and OH/Fe molar ratio. In comparison with PFC, the Fe (III) species and zeta potential of PFC-EPI-DMA were measured. Then their coagulation performance and coagulation kinetics for treating synthetic reactive dying wastewater were investigated. The results showed that the content of Fe(a) and Fe(b) in PFC-EPI-DMA and PFC coagulants decreased with increasing aging period. Compared to PFC, PFC-EPI-DMA had higher content of Fe(a) but lower content of Fe(b) and Fe(c). The zeta potentials of two coagulants decreased with increasing aging period within all tested pH range. For the treatment of reactive red 24, the color removal efficiency treated by PFC-EPI-DMA decreased, while that treated by PFC remained almost constant with increasing aging period. However, the color removal efficiencies of reactive blue 14 treated by two coagulants both decreased with increasing aging period. The results of floc aggregation process confirmed that with increasing aging period, the orders of floc growth rate, ratio and TWV treated by two coagulants were complicated.
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Affiliation(s)
- Baoyu Gao
- School of Environmental Science and Engineering, Shandong University, No 27 Shanda South Road, Jinan 250100, PR China. baoyugao
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50
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Reducing quartz gangue entrainment in sulphide ore flotation by high molecular weight polyethylene oxide. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/j.minpro.2010.07.009] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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