LAPSE:2021.0152
Published Article
LAPSE:2021.0152
Solid Circulating Velocity Measurement in a Liquid−Solid Micro-Circulating Fluidised Bed
Orlando L. do Nascimento, David A. Reay, Vladimir Zivkovic
April 16, 2021
Liquid−solid circulating fluidised beds (CFB) possess many qualities which makes them useful for industrial operations where particle−liquid contact is vital, e.g., improved heat transfer performance, and consequent uniform temperature, limited back mixing, exceptional solid−liquid contact. Despite this, circulating fluidised beds have seen no application in the micro-technology context. Liquid−solid micro circulating fluidised bed (µCFBs), which basically involves micro-particles fluidisation in fluidised beds within the bed of cross-section or inner diameter at the millimetre scale, could find potential applications in the area of micro-process and microfluidics technology. From an engineering standpoint, it is vital to know the solid circulating velocity, since that dictates the bed capability and operability as processing equipment. Albeit there are several studies on solid circulating velocity measurement in CFBs, this article is introducing the first experimental study on solid circulating velocity measurement in a CFB at micro-scale. The experimental studies were done in a novel micro-CFB which was fabricated by micro milling machining 1 mm2 cross-section channels in Perspex and in a 4 mm2 cross-section micro-CFB made by additive manufacturing technology. Soda-lime glass and polymethyl methacrylate (PMMA) micro-particles were employed as solid materials and tap water as the liquid medium. The digital particle image velocimetry (PIV) method was used as a measurement technique to determine the particle velocity in the micro-CFB system and validated by the valve accumulation technique using a novel magnetic micro-valve. The measured critical transition velocity, Ucr, is comparable to the particle terminal velocity, i.e., the normalised transition velocity is approximately 1 in line with macroscopic systems results and our previous study using simple visual observation. As in macroscopic CFB systems, Ucr decreased with solid inventory (1−9%) and finally becomes stable when the solid inventory is high enough (10−25%) and it increases with a reduction in particle size and density.
Keywords
circulating fluidised bed, digital PIV, liquid–solid fluidisation, micro-fluidised bed, wall effects
Suggested Citation
do Nascimento OL, Reay DA, Zivkovic V. Solid Circulating Velocity Measurement in a Liquid−Solid Micro-Circulating Fluidised Bed. (2021). LAPSE:2021.0152
Author Affiliations
do Nascimento OL: School of Engineering, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
Reay DA: School of Engineering, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
Zivkovic V: School of Engineering, Newcastle University, Newcastle upon Tyne NE1 7RU, UK
Journal Name
Processes
Volume
8
Issue
9
Article Number
E1159
Year
2020
Publication Date
2020-09-16
Published Version
ISSN
2227-9717
Version Comments
Original Submission
Other Meta
PII: pr8091159, Publication Type: Journal Article
Record Map
Published Article

LAPSE:2021.0152
This Record
External Link

doi:10.3390/pr8091159
Publisher Version
Download
Files
[Download 1v1.pdf] (3.3 MB)
Apr 16, 2021
Main Article
License
CC BY 4.0
Meta
Record Statistics
Record Views
331
Version History
[v1] (Original Submission)
Apr 16, 2021
 
Verified by curator on
Apr 16, 2021
This Version Number
v1
Citations
Most Recent
This Version
URL Here
https://psecommunity.org/LAPSE:2021.0152
 
Original Submitter
Calvin Tsay
Links to Related Works
Directly Related to This Work
Publisher Version