Acta Montanistica Slovaca (Dec 2004)

Kinetics of Grinding of Secondary Serpentine Raw Material at Cascade Operating Mode

  • Marek Matik,
  • Miroslava Václavíková,
  • Michal Lovás,
  • Štefan Jakabský,
  • Slavomír Hredzák,
  • Michal Neubauer

Journal volume & issue
Vol. 9, no. 4
pp. 423 – 427

Abstract

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The paper deals with the grinding of secondary serpentine material from the Dobšiná´s heap in a ball ceramic mill. The raw material was pre-sieved to prepare fraction of +250 –1,000 µm that was fed to the mill. During batch experiment an amount of oversize on the screen with a mesh size of 200 µm was observed as a function of time. Two speed modes were tested. Firstly, it was the mode designed by mill producer implicit from the structure of milling stand equipped by electromotor, friction gear onto driving shaft with given diameter. The speed of this original alignment attains 40 rmp. Secondly, it was cascade speed mode according to the Haase´s equation, namely 53 rmp, achieved by enlargement of driving shaft diameter. As to winning of required final product 90 % –200 µm, increased speed resulted in the shortening of grinding time from 17.5 to15.7 hour.

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