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Lee KH, Kim H, KuK JW, Chung JD, Park S, Kwon EE. Micro-bubble flow simulation of dissolved air flotation process for water treatment using computational fluid dynamics technique. Environ Pollut 2020; 256:112050. [PMID: 31481270 DOI: 10.1016/j.envpol.2019.01.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 12/30/2018] [Accepted: 01/03/2019] [Indexed: 06/10/2023]
Abstract
A dissolved air flotation (DAF) system is one of the water treatment processes that purifies contaminants through a buoyancy effect by attaching the moiety of micro-bubbles on their free surface. Since the DAF system was first used in the drinking water treatment in the 1960s, it has been recognized as an effective treatment for the water purification process. Most previous works laid great emphasis on the internal flow behaviors of fluid to improve the purification efficiency of the DAF system. Nevertheless, the practical implementation with a pilot plant indeed revealed some technical incompleteness for the DAF system. To circumvent for the technical incompleteness, numerical simulation based on computational fluid dynamics (CFD) has been carried out to understand the in-depth knowledge on internal flow phenomena in the DAF system. However, the standard k-ε turbulence model has been conventionally used in the most studies without any proper consideration process. Accordingly, the objectives of this study were to investigate the major effects on the internal flow behaviors for an efficient numerical simulation of DAF when a different turbulence model and micro-bubble parameters are used. As a result, the present study found that the standard k-ε model would be not proper for the internal flow simulation of the DAF process and a careful consideration would be required for a more accurate prediction. In addition, the present study examined a desirable internal flow pattern with various operating conditions of the micro-bubble. Consequently, the main findings of this study are expected to provide realistic information to related researchers for designing the DAF system with the optimal operating parameters.
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Affiliation(s)
- Kyun Ho Lee
- School of Mechanical and Aerospace Engineering, Sejong University, Seoul, 143-741, Republic of Korea
| | - Haedong Kim
- School of Mechanical and Aerospace Engineering, Sejong University, Seoul, 143-741, Republic of Korea
| | - Jung Won KuK
- School of Mechanical and Aerospace Engineering, Sejong University, Seoul, 143-741, Republic of Korea
| | - Jae Dong Chung
- School of Mechanical and Aerospace Engineering, Sejong University, Seoul, 143-741, Republic of Korea
| | - Sungsu Park
- School of Mechanical and Aerospace Engineering, Sejong University, Seoul, 143-741, Republic of Korea
| | - Eilhann E Kwon
- Department of Environment and Energy, Sejong University, Seoul, 143-741, Republic of Korea.
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Hu N, Shu T, Wu Z, Liu G, Li Z, Zhao Y, Yin H, Huang D. BS12-assisted flotation for the intensification of SNPs separation from CMP wastewater using a novel flotation column. J Hazard Mater 2018; 344:788-796. [PMID: 29172165 DOI: 10.1016/j.jhazmat.2017.11.028] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 11/15/2017] [Accepted: 11/16/2017] [Indexed: 06/07/2023]
Abstract
In view of the extremely small size, high stable dispersion and intricate colloidal nature of silica nanoparticles (SNPs) in chemical mechanical polishing (CMP) wastewater, they might not only have hazards for environment and human health, but also cause low separation efficiency by classical water-treatment processes. Thus, it would be an important challenge to develop an efficient flotation technology for the separation SNPs. For this propose, this paper firstly presented the interaction between SNPs and dodecyl dimethyl betaine (ambient-friendly surfactant). Secondly, a novel flotation column was developed for strengthening interfacial adsorption by micro-bubbles and enhancing foam drainage by internal of regular-decagonal hollow frustum (RHF). One vital finding was that the mixture of micro-bubbles and macro-bubbles was conducive to improving the flotation performance. Under the suitable operating conditions, the enrichment ratio (E) and recovery percentage (R) of SNPs could reach 30.4±1.5 and 90.8±4.5%, respectively. The great E and R were obtained simultaneously, revealing a good participation of RHF in the flotation. Without a doubt, owing to the low chemical reagent addition and the high flotation performance, it was clear that our flotation has huge implications for the separation of nanoparticles from their wastewaters.
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Affiliation(s)
- Nan Hu
- School of Chemical Engineering and Technology, Hebei University of Technology, No.8 Guangrong Road, Dingzi Gu, Hongqiao District, Tianjin, 300130, China
| | - Ting Shu
- School of Chemical Engineering and Technology, Hebei University of Technology, No.8 Guangrong Road, Dingzi Gu, Hongqiao District, Tianjin, 300130, China
| | - Zhaoliang Wu
- School of Chemical Engineering and Technology, Hebei University of Technology, No.8 Guangrong Road, Dingzi Gu, Hongqiao District, Tianjin, 300130, China.
| | - Guimin Liu
- School of Chemical Engineering and Technology, Hebei University of Technology, No.8 Guangrong Road, Dingzi Gu, Hongqiao District, Tianjin, 300130, China
| | - Zhiqiang Li
- School of Chemical Engineering and Technology, Hebei University of Technology, No.8 Guangrong Road, Dingzi Gu, Hongqiao District, Tianjin, 300130, China
| | - Yanli Zhao
- School of Chemical Engineering and Technology, Hebei University of Technology, No.8 Guangrong Road, Dingzi Gu, Hongqiao District, Tianjin, 300130, China
| | - Hao Yin
- School of Chemical Engineering and Technology, Hebei University of Technology, No.8 Guangrong Road, Dingzi Gu, Hongqiao District, Tianjin, 300130, China.
| | - Di Huang
- School of Chemical Engineering and Technology, Hebei University of Technology, No.8 Guangrong Road, Dingzi Gu, Hongqiao District, Tianjin, 300130, China
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Oishi Y, Kakimoto T, Yuan W, Kuno S, Yamashita H, Chiba T. Fetal Gene Therapy for Ornithine Transcarbamylase Deficiency by Intrahepatic Plasmid DNA- Micro-Bubble Injection Combined with Hepatic Ultrasound Insonation. Ultrasound Med Biol 2016; 42:1357-1361. [PMID: 26995155 DOI: 10.1016/j.ultrasmedbio.2015.10.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Revised: 10/04/2015] [Accepted: 10/12/2015] [Indexed: 06/05/2023]
Abstract
We evaluated the therapeutic efficacy of hepatic transfection of plasmid DNA using micro-bubbles and ultrasound insonation for fetal correction of ornithine transcarbamylase (OTC) deficiency in mice. Twenty-three sparse-fur heterozygous pregnant mice (day 16 of gestation) were divided into three groups: injection of plasmid-DNA micro-bubble mixture into fetal liver with ultrasound insonation (Tr, n = 11); control group 1 (C1), injection of plasmid-DNA micro-bubble mixture into fetal liver with no insonation (n = 5); and control group 2 (C2), injection of saline-micro-bubble mixture into fetal liver with ultrasound insonation (n = 7). Levels of blood ammonia and urinary orotic acid were significantly lower in the Tr group than in the C1 and C2 groups (p < 0.05, p < 0.01, respectively), whereas OTC activity was not different between groups. Therefore, ultrasound insonation with micro-bubbles enhanced plasmid DNA transfection into fetal mouse liver, leading to one of the therapeutic methods in ammonia metabolism. This might provide more time for OTC-deficient infants until liver transplantation.
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Affiliation(s)
- Yoshie Oishi
- National Center for Child Health and Development, Tokyo, Japan
| | | | - Wenji Yuan
- National Center for Child Health and Development, Tokyo, Japan
| | - Shuichi Kuno
- National Center for Child Health and Development, Tokyo, Japan
| | | | - Toshio Chiba
- National Center for Child Health and Development, Tokyo, Japan.
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Ren ST, Shen S, He XY, Liao YR, Sun PF, Wang B, Zhao WB, Han SP, Wang YL, Tian T. The Effect of Docetaxel-Loaded Micro-Bubbles Combined with Low-Frequency Ultrasound in H22 Hepatocellular Carcinoma-Bearing Mice. Ultrasound Med Biol 2016; 42:549-560. [PMID: 26651601 DOI: 10.1016/j.ultrasmedbio.2015.10.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Revised: 09/18/2015] [Accepted: 10/14/2015] [Indexed: 06/05/2023]
Abstract
A novel lipid micro-bubble (MB) loaded with docetaxel (DOC-MB) was investigated in a previous study. However, its anti-tumor effects and mechanism of action in combination with low-frequency ultrasound (LFUS) in vivo are still unclear. DOC-MBs containing 5.0 mg of DOC were prepared by lyophilization with modification via ultrasonic emulsification. Then, the effects of DOC-MBs combined with LFUS on tumor growth, proliferating cell nuclear antigen (PCNA) expression and cell apoptosis, as well as local DOC delivery, were investigated in H22 hepatocellular carcinoma (HCC)-bearing mice. Compared with the previously prepared DOC-MBs (1.6 mg of DOC loaded), the encapsulation efficiency (81.2% ± 3.89%) and concentration ([7.94 ± 0.04] × 10(9) bubbles/mL) of the DOC-MBs containing 5.0 mg of DOC were higher, but the bubble size (1.368 ± 0.004 μm) was smaller. After treatment with the DOC-MBs and LFUS, the H22 HCC growth inhibition rate was significantly increased, PCNA expression in tumor tissue was significantly inhibited and local release of DOC was induced. In conclusion, new DOC-MBs containing 5.0 mg of DOC were successfully prepared with a high encapsulation efficiency and superior bubble size and concentration, and their combination with LFUS significantly enhanced the anti-tumor effect of DOC in H22 HCC-bearing mice by inhibiting tumor cell proliferation and increasing local drug delivery.
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Affiliation(s)
- Shu-Ting Ren
- Department of Pathology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, China.
| | - Shu Shen
- Department of Pathology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, China; Second Division of In Vitro Diagnostic Reagents, National Institute of Food and Drug Control, Beijing, China
| | - Xin-Ying He
- Department of Pathology, Xi'an Medical University, Xi'an, China
| | - Yi-Ran Liao
- Department of Pathology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Peng-Fei Sun
- Department of Pathology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Bing Wang
- Department of Pathology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, China; Therapeutic Vaccines Engineering Center of Shaanxi Province, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Wen-Bao Zhao
- Department of Pathology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Shui-Ping Han
- Department of Pathology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Yi-Li Wang
- Department of Pathology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, China; Institute of Cancer Research, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Tian Tian
- Department of Pathology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, China
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