SAG Mill Liner Design
To a more significant degree than in other comminution devices, SAG Mill Liner Design and Configuration can have a substantial effect mill performance. In general terms, lifter spacing and angle, grate open area and aperture size, and pulp lifter design and capacity must be considered. Each of these topics has had a considerable
SAG Mill Grinding Circuit Design
AG and SAG mills are now the primary unit operation for the majority of large grinding circuits, and form the basis for a variety of circuit configurations. SAG circuits are common in the industry based on:
- High single-line capacities (leading to capital efficiency)
- The ability to mill a broad range of ore types in various circuit configurations, with reduced numbers of unit operations (and a corresponding reduction in the complexity of maintenance planning and coordination)
- Favourable operating costs (with contributions from reduced liner/media consumption relative to conventional circuits)
Though some trepidation concerning AG or SAG circuits accompanied design studies for some lime, such circuits are now
Stockpile Segregation
The video below graphically explains the common problem of Coarse Ore Stockpile Segregation. This topic relates to SAG Mill tonnage and the bad habit of putting bulldozers “dozers” on ore stockpiles.
THE BARRATT METHOD
Plants designed using The Barratt Method as published in the Book Mineral Processing Plant Design, Practice, and Control Proceedings, include:
- Alumbrera
- Batu Hijau
- Cadia (one consultant among others)
- Candelaria
- Clarabelle
Drop Weight tests (DWT) using JKMRC Rotary Breakage Tester
The Drop Weight tests (DWT) by JK is now replaced by the JKMRC Rotary Breakage Tester. It is faster as confirmed by Tony and now used by many since its intro http://www.min-eng.com
In an AG/SAG mill there are two main mechanisms of breakage, namely impact (high energy) and abrasion (low energy). The industry accepted
What Ore Testing is Required For Mill Selection
Beginners might ask what grinding test data is required in order to properly size a grinding mill. After the grind requirements are established, testing for the selection of comminution circuits and mill size can be initiated and can include the following:
- Primary Autogenous Media Competency
- Primary Autogenous and Semi-Autogenous Pilot Plant
- Secondary Autogenous (Pebble) Testing
- Impact Crushing – Bond Work Index
- Rod Mill Grindability – Bond Work Index
- Ball Mill Grindability – Bond Work Index
- Abrasion Index
- Crushing, Grinding and Concentration Pilot Plant
SAG & AG Mills can be sized according to any of the most appropriate methods of rock
SAG Mill Feed Chute Design| Long Life | Wear Resistant
This design of SAG mill feed chute lasted 9 months seeing 90,000 TPD. It is 600 brinell chrome steel.
With the big liners on the bottom of the chute you need to get a Chevron cast into the top to push the feed out to the sides for the first little while and then as the chevron wears it will start to come back