Benchmarking: Bond - Copper Mountain - Revision history

Munashe Kurisa: /* Modelling */

2020-05-20T16:13:38Z

Modelling

Munashe Kurisa: /* Modelling */

2020-05-19T23:52:25Z

Modelling

Munashe Kurisa: /* Modelling */

2020-05-19T23:29:57Z

Modelling

Alex Doll: /* Model Tuning */

2020-05-19T22:54:38Z

Model Tuning

Alex Doll: /* Model Tuning */

2013-03-21T19:00:11Z

Model Tuning

Alex Doll: /* Model Tuning */

2013-03-21T18:56:28Z

Model Tuning

Alex Doll at 18:55, 1 January 2013

2013-01-01T18:55:10Z

Alex Doll: /* Discussion */

2012-12-03T05:24:42Z

Discussion

Alex Doll: /* Discussion */

2012-12-03T05:23:12Z

Discussion

Alex Doll: /* Modelling */

2012-12-03T05:16:38Z

Modelling

@@ Line 65: / Line 65: @@
 * Assume liner thickness of 6 inches in SAG, 4.5 inches in ball mill.
 * Model predicted throughput: 1499 t/h on Pit 3 ore and 1488 t/h on Pit 2 ore.
 Result for default model conditions:

@@ Line 59: / Line 59: @@
 ===Modelling===
-[[file:BenchmarkingModel-CopperMt.png|thumb|Screenshot of model]]
+[[file:CopperMtn-pit2.png|thumb|Screenshot of pit 2 model]]
 * Assume the crushing work index is similar to the rod mill: 20 (metric).
 * Default SSBM contingency for SABC circuit is 0.10.
@@ Line 81: / Line 82: @@
 {| class="wikitable" border="1"
 |-
 |-
-| Model
+| Model || 1488 t/h || 1499 t/h
 |-
-| Measured
+| Measured || 1600 t/h || 1600 t/h
 |-
-| Difference
+| Difference || 112 t/h || 101 t/h
 |-
-| Difference
+| Difference || 7% || 6.3%
 |}

@@ Line 63: / Line 63: @@
 * Default SSBM contingency for SABC circuit is 0.10.
 * Assume liner thickness of 6 inches in SAG, 4.5 inches in ball mill.
-* Model predicted throughput: 1455 t/h on Pit 3 ore and 1445 t/h on Pit 2 ore.
+* Model predicted throughput: 1499 t/h on Pit 3 ore and 1488 t/h on Pit 2 ore.
 Result for default model conditions:

← Older revision		Revision as of 22:54, 19 May 2020
Line 92:		Line 92:
	* Raising the SAG speed to 78% of critical speed (10.4 RPM) has little effect due to the drop-off in power observed in a Loveday model using Barratt's published <i>Power Numbers</i> above 76% of critical speed.		* Raising the SAG speed to 78% of critical speed (10.4 RPM) has little effect due to the drop-off in power observed in a Loveday model using Barratt's published <i>Power Numbers</i> above 76% of critical speed.
	* The model predicts a '''negative''' phantom cyclone effect. This is an odd result, but does match one observation on a hard ore (Boddington circuit; private communication with M. Sherman).		* The model predicts a '''negative''' phantom cyclone effect. This is an odd result, but does match one observation on a hard ore (Boddington circuit; private communication with M. Sherman).
−
−	===Model Tuning===
−	The Bond/Barratt model is tuned using a contingency on the Single Stage Ball Mill specific energy consumption estimate (E<sub>ssbm</sub>).
−
−	* The SSBM contingency factor would be back-calculated as 0.01 based on the data set above.
−
−
−	Changing the SAG mill to the simplified Morrell model results in a much lower mill power draw estimate: 82.8% of rated output. This is much too low and this mill must be modelled with a higher ''k-factor''; likely between 1.35 and 1.40. Unfortunately, without actual motor power measurements, this factor cannot be tuned.
−
−	Changing the SAG mill to the Austin model results in a lower mill power draw estimate: 78.4% of rated output. This is also unlikely and the mine would be operating at a higher power draw than the Austin model predicts. The lower SAG power draw drives the T80 estimate very coarse, roughly 10 mm. The predicted throughput is about 5% lower than using the Loveday/Barratt SAG model.

← Older revision		Revision as of 19:00, 21 March 2013
Line 101:		Line 101:
	Changing the SAG mill to the simplified Morrell model results in a much lower mill power draw estimate: 82.8% of rated output. This is much too low and this mill must be modelled with a higher ''k-factor''; likely between 1.35 and 1.40. Unfortunately, without actual motor power measurements, this factor cannot be tuned.		Changing the SAG mill to the simplified Morrell model results in a much lower mill power draw estimate: 82.8% of rated output. This is much too low and this mill must be modelled with a higher ''k-factor''; likely between 1.35 and 1.40. Unfortunately, without actual motor power measurements, this factor cannot be tuned.

−	Changing the SAG mill to the Austin model results in a lower mill power draw estimate: 78.4% of rated output. This is also unlikely and the mine would be operating at a higher power draw than the Austin model predicts.	+	Changing the SAG mill to the Austin model results in a lower mill power draw estimate: 78.4% of rated output. This is also unlikely and the mine would be operating at a higher power draw than the Austin model predicts. The lower SAG power draw drives the T80 estimate very coarse, roughly 10 mm. The predicted throughput is about 5% lower than using the Loveday/Barratt SAG model.

← Older revision		Revision as of 18:56, 21 March 2013
Line 100:		Line 100:

	Changing the SAG mill to the simplified Morrell model results in a much lower mill power draw estimate: 82.8% of rated output. This is much too low and this mill must be modelled with a higher ''k-factor''; likely between 1.35 and 1.40. Unfortunately, without actual motor power measurements, this factor cannot be tuned.		Changing the SAG mill to the simplified Morrell model results in a much lower mill power draw estimate: 82.8% of rated output. This is much too low and this mill must be modelled with a higher ''k-factor''; likely between 1.35 and 1.40. Unfortunately, without actual motor power measurements, this factor cannot be tuned.
		+
		+	Changing the SAG mill to the Austin model results in a lower mill power draw estimate: 78.4% of rated output. This is also unlikely and the mine would be operating at a higher power draw than the Austin model predicts.

@@ Line 1: / Line 1: @@
 [[category: Benchmarking]]
 [[category: Bond/Barratt Model]]
 ==Benchmarking: Bond/Barratt - Copper Mountain==

@@ Line 90: / Line 90: @@
 * The assumed crushing work index (20) suggests a very competent ore compared to most in British Columbia &mdash; this matches comments at the SAG conference.  Assuming a lower work index of 10 results in a throughput of 1505 t/h (6.1%  difference versus the measured throughput).
 * Raising the SAG speed to 78% of critical speed (10.4 RPM) has little effect due to the drop-off in power observed in a Loveday model using Barratt's published <i>Power Numbers</i> above 76% of critical speed.
-* The model predicts a '''negative''' phantom cyclone effect.  This is an odd result, but does match one observation on a hard ore (Boddington circuit; private communication with M. Sherman).  Changing to a ''Raw Bond/Barratt model'' gives a slightly higher throughput of 1473 t/h by ignoring the phantom cyclone effect prediction.
+* The model predicts a '''negative''' phantom cyclone effect.  This is an odd result, but does match one observation on a hard ore (Boddington circuit; private communication with M. Sherman).
 ===Model Tuning===

@@ Line 87: / Line 87: @@
 ** The ball mills are likely operating at close to this power draw.
 ** The SAG mill actual power draw (measured at the shell) is most probably higher than 92%.
-* The liner effective thickness is unknown and may be thinner than assumed &mdash; this would increase the power draw in the mills and increase the tonnage.  Changing the effective liner thickness of the SAG mill to 4.5 inch and the ball mills to 3.0 inches results in 1500 t/h throughput prediction (6.7% difference versus the measured throughput).
+* The liner effective thickness is unknown and may be thinner than assumed &mdash; this would increase the power draw in the mills and increase the tonnage.  Changing the effective liner thickness of the SAG mill to 4.5 inch and the ball mills to 3.0 inches results in 1490 t/h throughput prediction (7.1% difference versus the measured throughput).
-* The assumed crushing work index (20) suggests a very competent ore compared to most in British Columbia &mdash; this matches comments at the SAG conference.  Assuming a lower work index of 10 results in a throughput of 1513 t/h (5.6%  difference versus the measured throughput).
+* The assumed crushing work index (20) suggests a very competent ore compared to most in British Columbia &mdash; this matches comments at the SAG conference.  Assuming a lower work index of 10 results in a throughput of 1505 t/h (6.1%  difference versus the measured throughput).
 * Raising the SAG speed to 78% of critical speed (10.4 RPM) has little effect due to the drop-off in power observed in a Loveday model using Barratt's published <i>Power Numbers</i> above 76% of critical speed.
 ===Model Tuning===

@@ Line 62: / Line 62: @@
 * Default SSBM contingency for SABC circuit is 0.10.
 * Assume liner thickness of 6 inches in SAG, 4.5 inches in ball mill.
-* Model predicted throughput: 1462 t/h on Pit 3 ore and 1452 t/h on Pit 2 ore.
+* Model predicted throughput: 1455 t/h on Pit 3 ore and 1445 t/h on Pit 2 ore.
 Result for default model conditions:
@@ Line 71: / Line 71: @@
 |-
 | Model
-| 1462 t/h
+| 1455 t/h
 |-
 | Measured
@@ Line 77: / Line 77: @@
 |-
 | Difference
-| 138 t/h
+| 145 t/h
 |-
 | Difference
-| 9.0%
+| 9.5%
 |}