Journal of Advanced Materials and Technologies

Journal of Advanced Materials and Technologies

Effect of suspension pH and nozzle diameter on the morphology and flowability of alumina - zircon granules fabricated by a spray dryer

Document Type : Original Reaearch Article

Authors
Leila Sharifi 1
Mahdi Kalantar 2
1 Ph.D. Candidate, Materials Engineering Group, Department of Mining and Metallurgical Engineering, Yazd University, Yazd, Iran.
2 Assistant Professor, Materials Engineering Group, Department of Mining and Metallurgical Engineering, Yazd University, Yazd, Iran.
10.30501/jamt.2026.581581.1363
Abstract
In this study, alumina-zircon granules were prepared under various conditions using a spray dryer. The primary challenge of this research was phase separation resulting from the density difference between alumina and zircon. Therefore, identifying optimal spray-drying conditions to obtain granules without zircon segregation was the main objective. Alumina suspensions containing 15 wt.% zircon and 2 wt.% dispersant were prepared at pH values of 4, 9.5, and 11, and granules were produced using a spray dryer equipped with a 700 μm nozzle. In another part of the study, the effect of spray dryer nozzle size on the morphology and flowability of the granules was investigated. The granules obtained from the alumina-zircon suspension containing 2 wt.% dispersant at pH 9 and prepared using a spray dryer equipped with a 1.5 mm nozzle exhibited excellent flow properties, including a repose angle of 28°, apparent density of 1.02 g/cm³, tapped density of 1.13 g/cm³, Hausner ratio of 1.11, and Carr’s index of 9.9, making them suitable for pressing.
Keywords
Alumina-Zircon Suspension
Granulation
Spray Drying
Suspension pH
Flowability
Subjects
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Journal of Advanced Materials and Technologies
Volume 15, Issue 2
Summer 2026
Pages 31-45

  • Receive Date 20 May 2026
  • Revise Date 25 June 2026
  • Accept Date 16 August 2026