Benchmarking: Bond - Macraes - Revision history

Alex Doll: /* Comparison */

2017-06-15T15:34:54Z

Comparison

← Older revision		Revision as of 15:34, 15 June 2017
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	! !! !! Survey 5 !! Survey 4 !! Survey 3 !! Survey 2 !! Survey 1 !! Overall<br>Average		! !! !! Survey 5 !! Survey 4 !! Survey 3 !! Survey 2 !! Survey 1 !! Overall<br>Average
	\|-		\|-
	\| SAG specific ~~power~~ \|\| \|\|-5.3% \|\|-5.0% \|\| 6.3% \|\| 0.5% \|\| 2.2% \|\| -0.2%		\| SAG specific energy \|\| \|\|-5.3% \|\|-5.0% \|\| 6.3% \|\| 0.5% \|\| 2.2% \|\| -0.2%
	\|-		\|-
	\| ball mill specific ~~power~~ \|\| \|\|-6.3% \|\|-4.7% \|\| 3.6% \|\| 1.9% \|\| 3.2% \|\| -0.5%		\| ball mill specific energy \|\| \|\|-6.3% \|\|-4.7% \|\| 3.6% \|\| 1.9% \|\| 3.2% \|\| -0.5%
	\|-		\|-
	\| total specific ~~power~~ \|\| \|\|-6.8% \|\|-3.8% \|\| 5.4% \|\| 1.4% \|\| 2.9% \|\| -0.2%		\| total specific energy \|\| \|\|-6.8% \|\|-3.8% \|\| 5.4% \|\| 1.4% \|\| 2.9% \|\| -0.2%
	\|-		\|-
	\| transfer size, T80 \|\| \|\|428.3% \|\|-39.7% \|\| 148.8% \|\| 21.9% \|\| 59.1% \|\| 123.7%		\| transfer size, T80 \|\| \|\|428.3% \|\|-39.7% \|\| 148.8% \|\| 21.9% \|\| 59.1% \|\| 123.7%

Alex Doll: /* Model Results */

2017-06-15T15:34:27Z

Model Results

← Older revision		Revision as of 15:34, 15 June 2017
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	! !! !! Survey 5 !! Survey 4 !! Survey 3 !! Survey 2 !! Survey 1		! !! !! Survey 5 !! Survey 4 !! Survey 3 !! Survey 2 !! Survey 1
	\|-		\|-
	\| SAG specific ~~power~~ \|\| kW at shell \|\| 3.41 \|\| 4.56 \|\| 4.36 \|\| 3.82 \|\| 3.68		\| SAG specific energy \|\| kWh/t at shell \|\| 3.41 \|\| 4.56 \|\| 4.36 \|\| 3.82 \|\| 3.68
	\|-		\|-
	\| ball mill specific ~~power~~ \|\| kW at shell \|\| 7.59 \|\| 7.91 \|\| 7.67 \|\| 7.54 \|\| 7.43		\| ball mill specific energy \|\| kWh/t at shell \|\| 7.59 \|\| 7.91 \|\| 7.67 \|\| 7.54 \|\| 7.43
	\|-		\|-
	\| total specific ~~power~~ \|\| kW at shell \|\| 11.00 \|\| 12.5 \|\| 12.02 \|\| 11.36 \|\| 11.11		\| total specific energy \|\| kWh/t at shell \|\| 11.00 \|\| 12.5 \|\| 12.02 \|\| 11.36 \|\| 11.11
	\|-		\|-
	\| transfer size, T<sub>80</sub><br>to achieve E<sub>SAG</sub>/E<sub>ball</sub> ratio \|\| µm \|\| 4200\|\| 2000 \|\| 2000 \|\| 2700 \|\| 3250		\| transfer size, T<sub>80</sub><br>to achieve E<sub>SAG</sub>/E<sub>ball</sub> ratio \|\| µm \|\| 4200\|\| 2000 \|\| 2000 \|\| 2700 \|\| 3250
	\|}		\|}

	It is important to remember that the Bond/Barratt equation for total circuit ~~power~~ (E<sub>total</sub>) is independent of transfer size. The transfer size is only used to split total circuit power between the SAG and ball mills. The difference between measured and predicted transfer sizes only affects the split of power between the milling stages and not the overall circuit power.		It is important to remember that the Bond/Barratt equation for total circuit specific energy (E<sub>total</sub>) is independent of transfer size. The transfer size is only used to split total circuit power between the SAG and ball mills. The difference between measured and predicted transfer sizes only affects the split of power between the milling stages and not the overall circuit power.

	===Comparison===		===Comparison===

Alex Doll: /* Interpretation and Interpolation */

2017-06-15T15:32:44Z

Interpretation and Interpolation

← Older revision		Revision as of 15:32, 15 June 2017
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	! !! !! Survey 5 !! Survey 4 !! Survey 3 !! Survey 2 !! Survey 1		! !! !! Survey 5 !! Survey 4 !! Survey 3 !! Survey 2 !! Survey 1
	\|-		\|-
	\| SAG specific ~~power~~ \|\| kW at shell \|\| 3.6 \|\| 4.8 \|\| 4.1 \|\| 3.8 \|\| 3.6		\| SAG specific energy \|\| kWh/t at shell \|\| 3.6 \|\| 4.8 \|\| 4.1 \|\| 3.8 \|\| 3.6
	\|-		\|-
	\| ball mill specific ~~power~~ \|\| kW at shell \|\| 8.1 \|\| 8.3 \|\| 7.4 \|\| 7.4 \|\| 7.2		\| ball mill specific energy \|\| kWh/t at shell \|\| 8.1 \|\| 8.3 \|\| 7.4 \|\| 7.4 \|\| 7.2
	\|-		\|-
	\| total specific ~~power~~ \|\| kW at shell \|\| 11.8 \|\| 13.0 \|\| 11.4 \|\| 11.2 \|\| 10.8		\| total specific energy \|\| kWh/t at shell \|\| 11.8 \|\| 13.0 \|\| 11.4 \|\| 11.2 \|\| 10.8
	\|-		\|-
	\| grindability, Wi<sub>RM</sub> \|\| kWh/t \|\| 9.5 \|\| 10.1 \|\| 9.8 \|\| 8.8 \|\| 9.5		\| grindability, Wi<sub>RM</sub> \|\| kWh/t \|\| 9.5 \|\| 10.1 \|\| 9.8 \|\| 8.8 \|\| 9.5

Alex Doll: /* Model Results */

2015-01-31T19:15:47Z

Model Results

← Older revision		Revision as of 19:15, 31 January 2015
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	===Model Results===		===Model Results===

	Model results:

	{\| class="wikitable"		{\| class="wikitable"

Alex Doll at 05:07, 1 February 2014

2014-02-01T05:07:06Z

← Older revision		Revision as of 05:07, 1 February 2014
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			[[category: Benchmarking]]
			[[category: Bond/Barratt Model]]
			[[category:Bibliography]]
	==Benchmarking: Bond/Barratt Circuit Specific Energy Consumption - Macraes==		==Benchmarking: Bond/Barratt Circuit Specific Energy Consumption - Macraes==

Alex Doll: Created page with "==Benchmarking: Bond/Barratt Circuit Specific Energy Consumption - Macraes== ''Barns, K., Lane, G., Osten, K. & Scagliotta, N.'', '''Benchmarking Energy Efficiency - A Ca..."

2014-02-01T05:05:48Z

Created page with "==Benchmarking: Bond/Barratt Circuit Specific Energy Consumption - Macraes== ''Barns, K., Lane, G., Osten, K. & Scagliotta, N.'', '''Benchmarking Energy Efficiency - A Ca..."

New page

==Benchmarking: Bond/Barratt Circuit Specific Energy Consumption - Macraes==

''Barns, K., Lane, G., Osten, K. & Scagliotta, N.'', '''Benchmarking Energy Efficiency - A Case Study at Macraes Gold Mine''', Proceedings of the AusIMM MetPlant conference, Perth, Australia, September 2004.

===Raw data from paper===

The paper describes overall plant unit operation efficiency rather that specific grinding mill surveys, but does reference five surveys that are useful for benchmarking.

{| class="wikitable"
|-
! !! !! Survey 5 !! Survey 4 !! Survey 3 !! Survey 2 !! Survey 1
|-
| throughput || dry t/h || 536 || 454 || 493 || 514 || 527
|-
| SAG feed F80 || mm || 82.9 || 106.8 || 72.7 || 56.8 || 51.4
|-
| SAG specific power || kW at DCS || 3.84 || 5.04 || 4.32 || 4.02 || 3.76
|-
| ball mill specific power || kW at DCS || 8.60 || 8.76 || 7.78 || 7.86 || 7.63
|-
| transfer size, T80 || µm || 795 || 3318 || 804 || 2215 || 2043
|-
| cyclone overflow size, P80 || µm || 100 || 100 || 100 || 117 || 116
|-
| grindability, SPI || minutes || 40.7 || 46.3 || 43.2 || 34.7 || 40.5
|-
| grindability, WiBM || kWh/t || 10.3 || 11.6 || 11.3 || 11.9 || 11.4
|}

===Interpretation and Interpolation===

Assume that the power provided at the motor input is converted to shell power using 0.96 motor efficiency and 0.985 gear efficiency for an overall conversion of 0.9456.

The paper gives interpolated values for the rod mill work index, but those do not appear to be calibrated to a "Bond" style rod mill with wave liners. Use the WiRM calibration to SGI from the Example database, these are the interpolated rod mill work index numbers that can be used for the Bond/Barratt method. No crushing work index values are given; assume that WiC = WiRM for modelling.

{| class="wikitable"
|-
! !! !! Survey 5 !! Survey 4 !! Survey 3 !! Survey 2 !! Survey 1
|-
| SAG specific power || kW at shell || 3.6 || 4.8 || 4.1 || 3.8 || 3.6
|-
| ball mill specific power || kW at shell || 8.1 || 8.3 || 7.4 || 7.4 || 7.2
|-
| total specific power || kW at shell || 11.8 || 13.0 || 11.4 || 11.2 || 10.8
|-
| grindability, WiRM || kWh/t || 9.5 || 10.1 || 9.8 || 8.8 || 9.5
|}

The transfer sizes are assumed to be "as-measured" and have not been subjected to a 'phantom cyclone' fine removal. The transfer size in the Bond/Barratt model (because it excludes 'additional' fines) will be iterated to give the ESAG/Eball ratio reported. The different between the iterated T80 and the measured T80 will be assumed to be the "phantom cyclone effect".

Because full mill surveys aren't given, abbreviated model runs are used in this benchmarking rather than full models (there is no saved data to view).

Use Bond/Barratt SABC model with 10% SSBM contingency.

===Model Results===

Model results:

{| class="wikitable"
|-
! !! !! Survey 5 !! Survey 4 !! Survey 3 !! Survey 2 !! Survey 1
|-
| SAG specific power || kW at shell || 3.41 || 4.56 || 4.36 || 3.82 || 3.68
|-
| ball mill specific power || kW at shell || 7.59 || 7.91 || 7.67 || 7.54 || 7.43
|-
| total specific power || kW at shell || 11.00 || 12.5 || 12.02 || 11.36 || 11.11
|-
| transfer size, T80 to achieve ESAG/Eball ratio || µm || 4200|| 2000 || 2000 || 2700 || 3250
|}

It is important to remember that the Bond/Barratt equation for total circuit power (Etotal) is independent of transfer size. The transfer size is only used to split total circuit power between the SAG and ball mills. The difference between measured and predicted transfer sizes only affects the split of power between the milling stages and not the overall circuit power.

===Comparison===

Difference between model results and plant surveys:
{| class="wikitable"
|-
! !! !! Survey 5 !! Survey 4 !! Survey 3 !! Survey 2 !! Survey 1 !! Overall Average
|-
| SAG specific power || ||-5.3% ||-5.0% || 6.3% || 0.5% || 2.2% || -0.2%
|-
| ball mill specific power || ||-6.3% ||-4.7% || 3.6% || 1.9% || 3.2% || -0.5%
|-
| total specific power || ||-6.8% ||-3.8% || 5.4% || 1.4% || 2.9% || -0.2%
|-
| transfer size, T80 || ||428.3% ||-39.7% || 148.8% || 21.9% || 59.1% || 123.7%
|}