Skip to main content

Lund University Publications

LUND UNIVERSITY LIBRARIES

Experimental investigation on micromixing characteristics of coaxial mixers in viscous system

Liu, Baoqing LU ; Gao, Pengfei ; Sun, Ning ; Zhang, Yikun ; Jin, Zhijiang and Sunden, Bengt LU (2020) In Canadian Journal of Chemical Engineering 98(8). p.1815-1824
Abstract

An experimental investigation into the micromixing performance of coaxial mixers in a viscous system is reported, in which the iodide-iodate reaction system is chosen to quantitatively characterize the product distributions. The effects of feeding time, feeding position, impeller speed, inner impeller configuration, and operation mode on the segregation index, Xs, are examined. It is revealed that the feeding near the inner impeller benefits micromixing and should be regarded as the preferred position. The presence of the rotating outer impeller causes the micromixing performance of the coaxial mixer to be significantly better than the single-shaft mixer. While an increase in the outer impeller speed has a limited influence on... (More)

An experimental investigation into the micromixing performance of coaxial mixers in a viscous system is reported, in which the iodide-iodate reaction system is chosen to quantitatively characterize the product distributions. The effects of feeding time, feeding position, impeller speed, inner impeller configuration, and operation mode on the segregation index, Xs, are examined. It is revealed that the feeding near the inner impeller benefits micromixing and should be regarded as the preferred position. The presence of the rotating outer impeller causes the micromixing performance of the coaxial mixer to be significantly better than the single-shaft mixer. While an increase in the outer impeller speed has a limited influence on micromixing, the inner impeller speed is the dominant influencing factor, that is, the Xs decreases obviously when the inner impeller speed is increased. On the other hand, the coaxial mixers with multiple and axial inner impellers have a better micromixing performance at the same specific power consumption, PV, than that with single and radial inner impellers. Among the configurations consisting of a Rushton impeller (RT), six-straight-blade turbine impeller (SBT), and six-pitched (45°)-blade turbine impeller (PBT), the Xs of the coaxial mixer is always the smallest at the same PV when the PBT + RT configuration is used as the inner impeller. In addition, it is found that the difference in Xs that results from various operation modes is small in terms of power consumption; however, the co-rotation mode is still recommended for the micromixing of the coaxial mixer due to its excellent performance in general.

(Less)
Please use this url to cite or link to this publication:
author
; ; ; ; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
coaxial mixer, micromixing, segregation index, stirred tank
in
Canadian Journal of Chemical Engineering
volume
98
issue
8
pages
10 pages
publisher
Wiley-Blackwell
external identifiers
  • scopus:85082619467
ISSN
0008-4034
DOI
10.1002/cjce.23730
language
English
LU publication?
yes
id
c2e79af0-167a-4cb6-9c82-ac062eab7699
date added to LUP
2020-04-27 15:30:44
date last changed
2023-11-20 03:50:37
@article{c2e79af0-167a-4cb6-9c82-ac062eab7699,
  abstract     = {{<p>An experimental investigation into the micromixing performance of coaxial mixers in a viscous system is reported, in which the iodide-iodate reaction system is chosen to quantitatively characterize the product distributions. The effects of feeding time, feeding position, impeller speed, inner impeller configuration, and operation mode on the segregation index, Xs, are examined. It is revealed that the feeding near the inner impeller benefits micromixing and should be regarded as the preferred position. The presence of the rotating outer impeller causes the micromixing performance of the coaxial mixer to be significantly better than the single-shaft mixer. While an increase in the outer impeller speed has a limited influence on micromixing, the inner impeller speed is the dominant influencing factor, that is, the Xs decreases obviously when the inner impeller speed is increased. On the other hand, the coaxial mixers with multiple and axial inner impellers have a better micromixing performance at the same specific power consumption, P<sub>V</sub>, than that with single and radial inner impellers. Among the configurations consisting of a Rushton impeller (RT), six-straight-blade turbine impeller (SBT), and six-pitched (45°)-blade turbine impeller (PBT), the Xs of the coaxial mixer is always the smallest at the same P<sub>V</sub> when the PBT + RT configuration is used as the inner impeller. In addition, it is found that the difference in Xs that results from various operation modes is small in terms of power consumption; however, the co-rotation mode is still recommended for the micromixing of the coaxial mixer due to its excellent performance in general.</p>}},
  author       = {{Liu, Baoqing and Gao, Pengfei and Sun, Ning and Zhang, Yikun and Jin, Zhijiang and Sunden, Bengt}},
  issn         = {{0008-4034}},
  keywords     = {{coaxial mixer; micromixing; segregation index; stirred tank}},
  language     = {{eng}},
  number       = {{8}},
  pages        = {{1815--1824}},
  publisher    = {{Wiley-Blackwell}},
  series       = {{Canadian Journal of Chemical Engineering}},
  title        = {{Experimental investigation on micromixing characteristics of coaxial mixers in viscous system}},
  url          = {{http://dx.doi.org/10.1002/cjce.23730}},
  doi          = {{10.1002/cjce.23730}},
  volume       = {{98}},
  year         = {{2020}},
}