GM  Vol.1 No.2 , July 2011
A New Approach to the Calculation of Work Index and the Potential Energy of a Particulate Material
Abstract: The work index Wi was defined by F. Bond as the specific energy (kWh/ton) required to reduce a particulate material from infinite grain size to 100 microns. The calculation is based on the size-energy relationship e1,2=C.(1/x2n–1/x1n ) , which for n = 0.5, x1 = ∞ and x2 =100, by definition gives e∞, 100 = Wi and consequently C=10Wi. In theory, for a given material the value found for Wi.should be constant regardless of the measured sizes x1 and x2 used to calculate the constant C by measuring the energy e. In practice this is not so due to the fact that n ≠ 0.5 and many correction factors have been proposed to overcome this inadequacy experienced by accepting n= 0.5. The present paper proposes a simple way to calculate the appropriate exponent n using conventional grinding procedures. The same calculation can be used to calculate the true value of Wi and attribute a potential energy state to a material at any size.
Cite this paper: nullE. Stamboliadis, S. Emmanouilidis and E. Petrakis, "A New Approach to the Calculation of Work Index and the Potential Energy of a Particulate Material," Geomaterials, Vol. 1 No. 2, 2011, pp. 28-32. doi: 10.4236/gm.2011.12005.

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