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From Kelly and Spottiswood Intro Min Proc, Wiley, 1982. What is Comminution. From Wikipedia: Comminution describes the movement of the particle size distribution (grains, drops, bubbles) into a range of finer particle sizes . From Kelly and Spottiswood Intro Min Proc, Wiley, 1982.
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From Kelly and Spottiswood Intro Min Proc, Wiley, 1982 What is Comminution From Wikipedia: Comminution describes the movement of the particle size distribution (grains, drops, bubbles) into a range of finer particle sizes
From Kelly and Spottiswood Intro Min Proc, Wiley, 1982 Product can be shipped and used Directly in BF Comminution Critical in Mineral Processing grinding
From Kelly and Spottiswood Intro Min Proc, Wiley, 1982 2/17 Comminution in Landscape Dynamics Glacial abrasion Debris Flow weathering Saltation Sklar and Dietrich Down Stream Fining x Sternberg’s law
From Kelly and Spottiswood Intro Min Proc, Wiley, 1982 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
The Comminution Laws Rittinger (1867): xF After q events Kick (1885): Energy for each event DE=Constant After q events E = q DE 6/17 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
Instructive to look at energy as A function of size reduction for quartz After Hukki Rittenger Log Energy Input Grind Limit Kick Log Particle Size Kick (1885): Energy for each event DE=Constant Crushing Abrasion 7/17 A general Law For general case x—an average part. size Rittinger (1867): Ritinger works best at describing Abrasion- Kick at describing crushing Walker suggested a two parameter law
Question: What is relation of To Down Stream Fining Sternberg’s Law x 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
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
Quartz/Schist Ratio Sternberg-Kick Law Modified Law Suggested by Adams Wear –1/Distance Rittinger Law
Mineral Laws of Comminution Inform Geomorphic Laws of Comminution What about two parameter laws Sklar: shows very good comparison With lab simulations of fining a is wear What is n?