Difference between revisions of "Benchmarking: Ball Mill Power Draw Models"

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(Benchmarking: Ball Mill Power Draw - Fimiston)
(Benchmarking: Ball Mill Power Draw - Meadowbank)
Line 36: Line 36:
 
* Diameter inside shell: 18 ft
 
* Diameter inside shell: 18 ft
 
* Length (assumed to be flange-to-flange length): 29 ft
 
* Length (assumed to be flange-to-flange length): 29 ft
* Effective grinding length: 28.5 ft (from block flow diagram)
+
* Effective grinding length: 28.5 ft (using rule-of-thumb half-foot basis)
* Motor size: horsepower ( kW)
+
* Motor size: 6,000 horsepower (4,474 kW)
* Overflow mill assumed
+
* Overflow mill with synchronous motor assumed
   
 
The operating conditions of the May 2012 survey, including the pre-crushing circuit given as:
 
The operating conditions of the May 2012 survey, including the pre-crushing circuit given as:
Line 55: Line 55:
 
! Mill filling
 
! Mill filling
 
! Morrell Model, kW
 
! Morrell Model, kW
! Loveday/Barratt model, kW
+
! Nordberg model, kW
! Austin model, kW
 
 
|-
 
|-
 
| May 2012
 
| May 2012
 
| 4,341
 
| 4,341
 
| 30.6% v/v
 
| 30.6% v/v
| (-3.3%)
+
| 4,765 (+9.3%)
| (+7.3%)
+
| 4,423 (+1.9%)
| (-3.0%)
 
 
|}
 
|}

Revision as of 01:01, 27 January 2013

Benchmarking: Ball Mill Power Draw - Fimiston

  • Nelson, M; Valery, W; Morrell, S, Performance Characteristics and Optimisation of the Fimiston (KCGM) SAG Mill Circuit, Page 233 - 248, SAG 1996 Conference, Vancouver, Canada.
Survey Survey Power,
kW at input
Mill speed,
%critical
Total load,
%v/v
Pulp %solids,
w/w
Morrell SAG Model,
kW at input / shell
Nordberg Model,
kW at input / shell
Survey 1 3,864 68.3 38.7 72.0 3,933 / 3,776 3,592 / 3,345
  • Morrell model predicts 2% high
  • Nordberg model predicts 7% low

See details of benchmarking

Benchmarking: Ball Mill Power Draw - Meadowbank

  • Muteb, P. & Allaire, J., Meadowbank Mine Process Plant Throughput Increase, Proceedings of the Canadian Mineral Processors Annual General Meeting, Ottawa, Canada, January 2013.

The ball mill design given as:

  • Diameter inside shell: 18 ft
  • Length (assumed to be flange-to-flange length): 29 ft
  • Effective grinding length: 28.5 ft (using rule-of-thumb half-foot basis)
  • Motor size: 6,000 horsepower (4,474 kW)
  • Overflow mill with synchronous motor assumed

The operating conditions of the May 2012 survey, including the pre-crushing circuit given as:

  • Mill speed 14.19 rpm (75% critical)
  • Volumetric filling 30.6% v/v
  • Ball charge 30.6% v/v
  • Ore density 2.93 kg/L
  • Grindability: A×b 38.6; WiBM 10.9 kWh/t

Liners assumed to be an effective thickness of 3 inches. DCS power is assumed to be indicated (mill power measurements × 0.985 pinion × 0.96 motor eff equals power "at mill shell"). Model power measurements are shown "at DCS".

DCS Power, kW Mill filling Morrell Model, kW Nordberg model, kW
May 2012 4,341 30.6% v/v 4,765 (+9.3%) 4,423 (+1.9%)