Bernhard König, Stefan Puttinger, Stefan Pirker,
"Turbulent measurements within a gas stirred three-phase bubble column with multiple aeration plugs"
, in The Chinese Society for Metals (CSM): Proceedings of The 6th International Congress on the Science and Technology of Steelmaking, Vol. 6, Nummer 1, China Maschine Press, Beijing, Seite(n) 339-342, 5-2015, ISBN: 978-7-111-50125-1
Turbulent measurements within a gas stirred three-phase bubble column with multiple aeration plugs
Sprache des Titels:
Proceedings of The 6th International Congress on the Science and Technology of Steelmaking
Within the process of converter stirring three major problems triggered by the turbulent convective flow are the
subject of investigation. These are the request of fast and efficient mixing, minimising the erosion of refractory material, and
the flushing of non-metal inclusions. Therefore, the vessel is equipped with porous plugs located at the bottom and aerated
with inert gas. By increasing the amount of aeration gas (for improved mixing) higher velocities are enforced which erode the
refractory material faster and may induce beneficial conditions for slag entrainment.
To optimise the mixing behaviour while reducing the negative effects this work illustrates measurements from a lab scale
air/water/oil experiment. The measurements are based on a PIV method utilising three cameras and two different wavelength
lasers. This separation permits the investigation of the complete flow field with reduced resolution while monitoring a special
area of interest at higher temporal and spacial resolution while the phase separation is achieved with subsequent image
processing. The complete technique is introduced and applied to the big lab scale facility to investigate the phenomena in
a scaled process environment. Considerations on selecting a liquid as a substitute for the slag layer are presented and the
corresponding similarity is presented. Comparisons between different aeration periods concerning the erosive potential are
illustrated and an estimation of the mixing behaviour based on the turbulent kinetic energy is provided.