A1 Journal article (refereed), original research

Auto-Aspirated DAF Sparger Study on Flow Hydrodynamics, Bubble Generation and Aeration Efficiency


Open Access publication

Publication Details
Authors: Gradov Dmitry, Saren Andrey, Kauppi Janne, Ullakko Kari, Koiranen Tuomas
Publisher: MDPI
Publication year: 2020
Language: English
Related Journal or Series Information: Processes
Volume number: 8
Issue number: 11
Start page: 1
End page: 17
Number of pages: 17
eISSN: 2227-9717
JUFO-Level of this publication: 1
Permanent website address: https://www.mdpi.com/2227-9717/8/11/1498
Open Access: Open Access publication

Abstract

A novel auto-aspirated sparger is examined experimentally in a
closed-loop reactor (CLR) at lab scale using particle image velocimetry,
high-speed camera and oxygen mass transfer rate measurements.
State-of-the-art 3D printing technology was utilized to develop the
sparger design in stainless steel. An insignificant change in the bubble
size distribution was observed along the aerated flow, proving the
existence of a low coalescence rate in the constraint domain of the CLR
pipeline. The studied sparger created macrobubbles evenly dispersed in
space. In pure water, the produced bubble size distribution from 190 to
2500 μm is controlled by liquid flow rate. The bubble size dynamics
exhibited a power-law function of water flow rate approaching a stable
minimum bubble size, which was attributed to the ratio of the
fast-growing energy of the bubble surface tension over the kinetic
energy of the stream. Potentially, the stream energy can efficiently
disperse higher gas flow rates. The oxygen transfer rate was rapid and
depended on the water flow rate. The aeration efficiency below 0.4 kW/m3
was superior to the commonly used aerating apparatuses tested at lab
scale. The efficient gas dissolution technology has potential in water
treatment and carbon capture processes applications


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Last updated on 2021-16-03 at 12:47