What is Comminution

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What is Comminution
From Wikipedia Comminution describes the
movement of the particle size distribution
(grains, drops, bubbles) into a range of finer
particle sizes
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Comminution Critical in Mineral Processing
grinding
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Comminution in Landscape Dynamics
Glacial abrasion
Debris Flow
weathering
Saltation
Sklar and Dietrich
Down Stream Fining
x
Sternbergs law
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A Thing to Know
For a Given Energy What is the Reduction in
Particle Size The Comminution Laws
Main Result Suggest How Sternberg law for down
stream Fining could be modified by Mineral
Engineering Results
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The Comminution Laws
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From Kelly and Spottiswood Intro Min Proc, Wiley,
1982
Consider a simplistic comminution operation that
for each event reduces the particle size by a
factor of 1/2
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A general Law
For general case xan average part. size
Rittinger (1867)
Ritinger works best at describing Abrasion- Kick
at describing crushing
Walker suggested a two parameter law
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Question What is relation of
Kick
Rittinger
wear
Set E x (distance down stream) and x D
particle size
Is Sternberg
Kick
An alternative
Ritinger
Could it make a difference
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Sternberg-Kick Law
Finding in river headwaters
Log-log plot of representative particle size
(mm) vs. distance downstream, reproduced from
Fig 2 in Adams (1979).
Rittinger Law
Modified Law Suggested by Adams Wear 1/Distance
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Quartz/Schist Ratio
Sternberg-Kick Law
Modified Law Suggested by Adams Wear 1/Distance
Rittinger Law
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Sklar shows very good comparison With lab
simulations of fining
a is wear
What is n?