voller 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

voller grinding Product can be shipped and used Directly in BF From Kelly and Spottiswood Intro Min Proc, Wiley, 1982 Comminution Critical in Mineral Processing

voller Glacial abrasion Debris Flow Saltation Sklar and Dietrich weathering Comminution in Landscape Dynamics x Down Stream Fining 2/17 From Kelly and Spottiswood Intro Min Proc, Wiley, 1982 Sternberg’s law

voller A Thing to Know For a Given Energy What is the Reduction in Particle Size— The Comminution Laws From Kelly and Spottiswood Intro Min Proc, Wiley, 1982 Main Result Suggest How Sternberg law for down stream Fining could be modified by Mineral Engineering Results

voller From Kelly and Spottiswood Intro Min Proc, Wiley, 1982 The Comminution Laws Consider a simplistic comminution operation that for each event reduces the particle size by a factor of 1/2 Rittinger (1867): xFxF After q events Kick (1885): Energy for each event  E=Constant After q events E = q  E 6/17

voller Rittinger (1867): Kick (1885): Energy for each event  E=Constant A general Law For general case x—an average part. size Log Particle Size Log Energy Input Grind Limit Kick Rittenger Crushing Abrasion After Hukki Instructive to look at energy as A function of size reduction for quartz Ritinger works best at describing Abrasion- Kick at describing crushing 7/17 Walker suggested a two parameter law

voller x To Down Stream Fining Sternberg’s Law Question: What is relation of Kick Rittinger Set E = x (distance down stream) and x = D particle size Kick Is Sternberg Ritinger wear An alternative Could it make a difference

voller Log-log plot of representative particle size (mm) vs. distance downstream, reproduced from Fig 2 in Adams (1979). Sternberg-Kick Law Finding in river headwaters Modified Law Suggested by Adams Wear –1/Distance Rittinger Law

voller Rittinger Law Modified Law Suggested by Adams Wear –1/Distance Sternberg-Kick Law Quartz/Schist Ratio

voller Mineral Laws of Comminution  is wearWhat is n? Inform Geomorphic Laws of Comminution Sklar: shows very good comparison With lab simulations of fining What about two parameter laws