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INPUT   DATA

♥ EXAMPLE Of Input/Output

Title

	Known Input	Desired Result
Feed particle size, Xf			nm
Product particle size, Xp			nm
Throughput, Q			lb/day
Power required, P			hp

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OUTPUT   VARIABLES   &   GRAPHS

Variables	Energy	Units
♦  Hick's law		hp	Graphs:    Energy vs. Particle Size
♦  Rittinger's law		hp
♦  Bond's law		hp
♦  Bond work index, Ei		hp

Particle Size Reduction In Grinding Operation

The calculator is designed to determine appropriate operating conditions for a given grinding task (known material properties plus desired mill throughput and feed and product sizes). The energy expended in size reduction is theoretically proportional to the new surface area produced, since there is no change in the material, except size the creation of new surface. Three laws (Kick's, Rittinger's and Bond laws) have been proposed to relate size reduction to a single variable - the energy input to the mill. These can be expressed as follows:

   Kick's Law:      E = C_klog[X_f/X_p]

   Rittinger's Law:      E = C_r[1/X_p - 1/X_f]

   Bond Law:      E = 100E_i[1/√X_p - 1/√X_f]

where
     E = energy requirement
     X_f= feed particle size
     X_p= product particle size
     E_i= Bond work index, i.e. work required to reduce a unit weight from a theoretical infinite size to 80% passing 100 microns.
     C_i= experimental constant coefficients

Tips

    ◊ Use link EXAMPLE Of Input/Output  to demo data entry expectations and results; you may edit & use it as starting point

BIBLIOGRAPHY

• Theodore L; Nanotechnology,: Basic Calculations For Engineers And Scientists; John Wiley & Sons, New Jersey, 2006