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Effects of surface microbubbles on the adhesion between air bubble/oil droplet and graphite surfaces. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.130809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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2
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Wang C, Lü Y, Song C, Zhang D, Rong F, He L. Separation of emulsified crude oil from produced water by gas flotation: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 845:157304. [PMID: 35839883 DOI: 10.1016/j.scitotenv.2022.157304] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 07/01/2022] [Accepted: 07/08/2022] [Indexed: 06/15/2023]
Abstract
The development and production of oil and gas fields would eventually result in a considerable amount of oily generated water, posing serious risks to humans and the environment. Nowadays, the oil concentration in the drainage stream of the produced water is strictly regulated, and many countries have established strict emission standards. As an indispensable oily wastewater treatment technology, flotation technology has attracted much attention because of its maturity, economy, practicality, and relative efficiency. Firstly, this paper summarizes and compares flotation techniques, such as dissolved gas flotation, induced gas flotation, electroflotation, and compact flotation units widely used in produced water treatment offshore in recent years. Considering the complexity of the mechanism of oil removal by air flotation, the mechanism of the oil droplet-bubble interaction is further discussed. The effects of flocculant, PH, and salinity on the oil droplet-bubble interaction in the flotation process were summarized from the perspective of the microscopic colloidal interface, which has a specific guiding role in improving the oil removal efficiency in the gas flotation process. Finally, the research status of produced water treatment by air flotation is summarized, and the feasible research direction is put forward.
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Affiliation(s)
- Ce Wang
- College of Pipeline and Civil Engineering, China University of Petroleum (East China), Shandong, Qingdao 266580, China
| | - Yuling Lü
- College of Pipeline and Civil Engineering, China University of Petroleum (East China), Shandong, Qingdao 266580, China.
| | - Chao Song
- College of Pipeline and Civil Engineering, China University of Petroleum (East China), Shandong, Qingdao 266580, China
| | - Dechong Zhang
- Xianhe Oil Production Plant, Shengli Oilfield Company, Sinopec, Shandong, Dongying 257000, China
| | - Feng Rong
- College of Pipeline and Civil Engineering, China University of Petroleum (East China), Shandong, Qingdao 266580, China
| | - Limin He
- College of Pipeline and Civil Engineering, China University of Petroleum (East China), Shandong, Qingdao 266580, China
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Fan W, Li Y, Wang C, Duan Y, Huo Y, Januszewski B, Sun M, Huo M, Elimelech M. Enhanced Photocatalytic Water Decontamination by Micro-Nano Bubbles: Measurements and Mechanisms. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:7025-7033. [PMID: 33944552 DOI: 10.1021/acs.est.0c08787] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Despite recent advancements in photocatalysis enabled by materials science innovations, the application of photocatalysts in water treatment is still hampered due to low overall efficiency. Herein, we present a TiO2 photocatalytic process with significantly enhanced efficiency by the introduction of micro-nano bubbles (MNBs). Notably, the removal rate of a model organic contaminant (methylene blue, MB) in an air MNB-assisted photocatalytic degradation (PCD) process was 41-141% higher than that obtained in conventional macrobubble (MaB)-assisted PCD under identical conditions. Experimental observations and supporting mechanistic modeling suggest that the enhanced photocatalytic degradation is attributed to the combined effects of increased dissolution of oxygen, improved colloidal stability and dispersion of the TiO2 nanocatalysts, and interfacial photoelectric effects of TiO2/MNB suspensions. The maximum dissolved oxygen (DO) concentration of the MNB suspension (i.e., 11.7 mg/L) was 32% higher than that of an MaB-aerated aqueous solution (i.e., 8.8 mg/L), thus accelerating the hole oxidation of H2O on TiO2. We further confirmed that the MNBs induced unique light-scattering effects, consequently increasing the optical path length in the TiO2/MNB suspension by 7.6%. A force balance model confirmed that a three-phase contact was formed on the surface of the bubble-TiO2 complex, which promoted high complex stability and PCD performance. Overall, this study demonstrates the enhanced photocatalytic water decontamination by MNBs and provides the underlying mechanisms for the process.
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Affiliation(s)
- Wei Fan
- School of Environment, Northeast Normal University, Changchun 130117, China
| | - Yuhang Li
- School of Environment, Northeast Normal University, Changchun 130117, China
| | - Chunliang Wang
- School of Physics, Northeast Normal University, Changchun 130024, China
| | - Yutong Duan
- School of Environment, Northeast Normal University, Changchun 130117, China
| | - Yang Huo
- School of Physics, Northeast Normal University, Changchun 130024, China
| | - Brielle Januszewski
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520-8286, United States
| | - Meng Sun
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520-8286, United States
| | - Mingxin Huo
- School of Environment, Northeast Normal University, Changchun 130117, China
| | - Menachem Elimelech
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520-8286, United States
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4
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Investigation of bubble-particle attachment, detachment and collection efficiencies in a mechanical flotation cell. POWDER TECHNOL 2020. [DOI: 10.1016/j.powtec.2020.07.085] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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5
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Han C, Zhang H, Tan R, Shen Y, Wei D, Liu W. Effects of monohydric alcohols of varying chain lengths and isomeric structures on magnesite and dolomite flotation by dodecylamine. POWDER TECHNOL 2020. [DOI: 10.1016/j.powtec.2020.07.048] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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6
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Yan S, Yang X, Bai Z, Xu X, Wang H. Drop attachment behavior of oil droplet-gas bubble interactions during flotation. Chem Eng Sci 2020. [DOI: 10.1016/j.ces.2020.115740] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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7
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8
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Han Y, Xu X, Liu F, Wei W, Liu Z. Study of the theory of microbubble bursting to obtain bio-inspired alginate nanoparticles. Colloids Surf A Physicochem Eng Asp 2020. [DOI: 10.1016/j.colsurfa.2020.124494] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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9
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Reis AS, Reis Filho AM, Demuner LR, Barrozo MA. Effect of bubble size on the performance flotation of fine particles of a low-grade Brazilian apatite ore. POWDER TECHNOL 2019. [DOI: 10.1016/j.powtec.2019.09.029] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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10
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Zou X, Xu K, Wen H, Xue Y, Qu Y, Li Y. Efficient microalgae harvesting using a thermal flotation method with response surface methodology. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2019; 80:426-436. [PMID: 31596254 DOI: 10.2166/wst.2019.287] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Thermal pre-flocculation to enable dispersed air flotation is an economical and ecofriendly technology for harvesting microalgae from water. However, the underlying mechanism and optimal conditions for this method remain unclear. In this study, Chlorella vulgaris (C. vulgaris) and Scenedesmus obliquus (S. obliquus) were harvested using a thermal flotation process. The surface structure and characteristics (morphology, electricity, and hydrophobicity) of the microalgae were analyzed using FT-IR (Fourier transform infrared spectroscopy), SEM (scanning electron microscopy), zeta potential, and a hydrophobic test. Further, response surface methodology (RSM) was used to optimize the flotation process. The hydrophobicity of S. obliquus exceeded that of C. vulgaris; as such, under the thermal pre-flocculation, S. obliquus (88.16%) was harvested more efficiently than C. vulgaris (47.16%). Thermal pre-flocculation denatured the lipids, carbohydrate, and proteins of microalgal cell surfaces. This resulted in a decrease in the electrostatic repulsion between the cells and air bubbles. The highest harvesting efficiency was 91.96% at 70 °C, 1,412 rpm, and 13.36 min. The results of this study demonstrate the potential for economic and ecofriendly harvesting of microalgae for biofuels and other bioproducts industries.
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Affiliation(s)
- Xiaotong Zou
- School of Environmental Science and Engineering, Chang'an University, Xi'an 710054, China E-mail:
| | - Kaiwei Xu
- School of Environmental Science and Engineering, Chang'an University, Xi'an 710054, China E-mail:
| | - Hao Wen
- School of Environmental Science and Engineering, Chang'an University, Xi'an 710054, China E-mail:
| | - Yating Xue
- School of Environmental Science and Engineering, Chang'an University, Xi'an 710054, China E-mail:
| | - Yanhui Qu
- School of Environmental Science and Engineering, Chang'an University, Xi'an 710054, China E-mail:
| | - Yanpeng Li
- School of Environmental Science and Engineering, Chang'an University, Xi'an 710054, China E-mail: ; Key Laboratory of Subsurface Hydrology and Ecology in Arid Areas, Ministry of Education, Xi'an 710054, China and Shaanxi Key Laboratory of Land Consolidation, Xi'an 710075, China
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A Study of Bubble Mineralization by Modified Glass Microspheres Based on a High-Speed Dynamic Microscopic Test System. MINERALS 2019. [DOI: 10.3390/min9060350] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The microscopic study of bubble mineralization is an important means of flotation theory research. In order to visualize the research process, it is required that the particles have certain optical properties and the amount of bubbles is controllable. In this paper, the particles were glass microspheres modified with trimethylchlorosilane (TMCS). The modification effect was confirmed by Fourier-transform infrared spectroscopy (FTIR), contact angle measurements, and a flotation test. The FTIR analysis and flotation test verified that the functional group (-OH) of glass microspheres reacted with the functional group (-Si-Cl) of TMCS and that the glass microsphere surface was successfully modified. The results also showed that the contact angle and hydrophobicity of the glass microspheres of a given size increased with the increase of TMCS. A small glass microsphere required more TMCS during the modification step in order to have the same contact angle as a large glass microsphere. The microscopic process of bubble mineralization was captured by a high-speed dynamic analysis system. The probability of collision between large glass microspheres and bubbles was high, but so was the probability that the microspheres would detach from the bubble. Both the collision probability and the detachment probability between small glass microspheres and bubbles were small, and small glass microspheres were easily affected by the flotation fluid. Besides, small bubbles and fine glass microspheres had a higher flotation recovery than coarse glass microspheres and large bubbles.
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Xing Y, Zhang Y, Liu M, Xu M, Guo F, Han H, Gao Z, Cao Y, Gui X. Improving the floatability of coal with varying surface roughness through hypobaric treatment. POWDER TECHNOL 2019. [DOI: 10.1016/j.powtec.2019.01.058] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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13
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Oliveira GA, Monje-Ramirez I, Carissimi E, Rodrigues RT, Velasquez-Orta SB, Mejía ACC, Orta Ledesma MT. The effect of bubble size distribution on the release of microalgae proteins by ozone-flotation. Sep Purif Technol 2019. [DOI: 10.1016/j.seppur.2018.10.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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14
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Role of DTAB and SDS in Bubble-Particle Attachment: AFM Force Measurement, Attachment Behaviour Visualization, and Contact Angle Study. MINERALS 2018. [DOI: 10.3390/min8080349] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Atomic force microscopy (AFM) and contact angle measurements were used to study the role of dodecyltrimethylammonium bromide (DTAB) and sodium dodecyl sulphate (SDS) in bubble-particle attachment. The results show that the forces between bubbles and the hydrophilic glass particle were always repulsive in the absence of DTAB and SDS. An attractive hydrophobic force was induced when the particles became hydrophobic, and the force was proportional to the water contact-angle. In the presence of DTAB and SDS, the cationic head group of DTAB adsorbed onto the negative hydrophilic glass surface as a monolayer and thus induced a hydrophobic force. However, at a high DTAB concentration, the DTAB molecules began to adsorb as a bilayer, reverting back to a hydrophilic surface. The hydrophobic force disappeared and the water film between the bubble and particle was stabilised under the repulsive double-layer force. The anionic SDS molecules could not adsorb onto the hydrophilic glass surface. The repulsive force always dominated the bubble-particle interaction. In the case of hydrophobic glass, the hydrophobic force decreased, and even disappeared, with the addition of DTAB and SDS. All the findings from the AFM force curves were consistent with the attachment behaviour and contact angle results.
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