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Journal of Sustainable Metallurgy

, Volume 5, Issue 2, pp 172–180 | Cite as

Air-Blast Cross-Flow Atomization of Cold Fluids

  • Alexander VadilloEmail author
  • Sina Mostaghel
  • Mansoor Barati
Thematic Section: Slag Granulation
  • 37 Downloads
Part of the following topical collections:
  1. Slag Granulation

Abstract

The motivation for this work is to gain a better understanding of how particle characteristic can be controlled when metallurgical slags are atomized in cross-flow air atomization. The effect of certain process parameters on the characteristics of liquid droplets produced by air-blast atomization has been investigated using water, castor oil, and glycerin. The gas-to-liquid ratio as well as the distance between the liquid and air stream were manipulated to understand their effect on the particle shape and size. The effect of liquid viscosity on the size and shape of droplets was also investigated. Droplets were observed in-flight with the use of shadow imaging, which were analyzed to provide information regarding the mentioned characteristics. It was found that a single correlation expressed as kinetic energy of the atomizing air per unit mass of the atomized liquid can explain the effects of gas/liquid ratio and distance between the air nozzle and crash point. The average particle size decreased with an increase in the gas-to-liquid flow rate ratio, increased with increasing distance between the liquid and air stream, and increased with increasing viscosity. The aspect ratio was consistent and close to unity for all water atomization experiments.

Keywords

Metallurgical slag Dry granulation Break-up mechanism Atomization 

List of symbols

Ek

Gas kinetic energy rate (J/s)

Es

Surface energy consumption rate (J/s)

En

Viscous energy dissipation rate (J/s)

mg

Gas mass flow rate (g/s)

ml

Liquid mass flow rate (g/s)

vg

Gas velocity (m/s)

v

Difference between gas and liquid velocities (m/s)

ρl

Liquid density (g/m3)

ρg

Gas density (g/m3)

n

Number of droplets

γ

Surface tension (J/m2)

μ

Viscosity (poise)

d32

Sauter mean diameter (m)

β

Fraction of kinetic energy used to overcome surface energy

A

Impact area between gas and liquid, at the point of granulation (m2)

A0

Area of the air nozzle (m2)

L

Distance between air stream and liquid stream (m)

θ

Angle of expansion (deg)

Notes

Acknowledgements

Financial supports by OCE (Project # 23544), NSERC (Grant # CRDPJ 484828 - 15), and Hatch Ltd. are gratefully acknowledged.

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Copyright information

© The Minerals, Metals & Materials Society 2019

Authors and Affiliations

  1. 1.Department of Materials Science and EngineeringUniversity of TorontoTorontoCanada
  2. 2.Formerly with Hatch Ltd.MississaugaCanada
  3. 3.Aurubis AGHamburgGermany

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