### SAG mill ball charge determination and its influence on ...

SAG mill ball charge determination and its influence on mill drive requirements Abstract: In semi-autogenous grinding (SAG), the grinding mill inventory, (i.e. volume of total charge, volume of ball charge, etc.) is important in determining the optimum operating condition for maximum production (tph), minimum specific energy (kwh/t) or lowest cost ($/t). A two-dimensional graphical method is ...

More### Mill Charge - an overview ScienceDirect Topics

SAG mills of comparable size but containing say 10% ball charge (in addition to the rocks), normally, operate between 70 and 75% of the critical speed. Dry Aerofall mills are run at about 85% of the critical speed. The breakage of particles depends on the speed of rotation. Working with a 7.32 m diameter and 3.66 m long mill, Napier-Munn et al. [4] observed that the breakage rate for the finer ...

More### Mill Steel Charge Volume Calculation

We can calculate the steel charge volume of a ball or rod mill and express it as the % of the volume within the liners that is filled with grinding media. While the mill is stopped, the charge volume can be gotten by measuring the diameter inside the liners and the distance from the top of the charge to the top of the mill. The % loading or change volume can then be read off the graph below or ...

More### SAG/AG SCU - Millwatch

Maintaining an optimum charge in a SAG mill remains one of the fundamentals for efficient mill processing. If the charge level or the ball to charge ratio is incorrect, breaking liners and/or increasing power consumption is inevitable and can only result in degraded mill efficiency. To minimize reline time, it is critical to set the charge height at an optimum level. Setting the charge level ...

More### SAGMILLING.COM .:. tools_millfilling

Enter the number of lifters that are exposed above the mill charge. Fractions are acceptable and should be used in the case where the charge does not sit uniformly in the mill. For example, you may have 29 rows exposed at the discharge end of the mill, and only 28 exposed at the feed end. If so, enter 28.5 for the number of exposed lifters. Calculated Mill Charge: % Calculation backup: The ...

More### ERSEL Ağır Makine San. ve Tic. A.Ş.

* Semi-autogenous (SAG) grinding is a grinding process carried out with small amount of ball charge (4-15%) unlike ball mills and with the help of bigger parts crumbling the smaller parts of ore. * To achieve this type of grinding, SAG mills with large diameter and short length have been developed to take advantage of the kinetic energy of the free falling coarse particles. * SAG mills are ...

More### Benchmarking: Amelunxen SGI - Agnico Eagle -

SAG mill ball charge = 10.6 % vol; SAG mill discharge % solids = 84% weight; SAG mill speed 8.59 RPM (53.4% of critical) E SAG at mill shell = 1283/210 = 6.11 kWh/t (to achieve DCS power of 1350 kW requires 14% vol mill load) ball mill power draw (sum of 2 mills, at motor input) = 1422 kW (at mill shell = 2 × 674 kW = 1348 kW) ball mill % solids = 83% weight (to achieve 1424 kW, assume 30% ...

More### The Effect of the Grinding Charge Trajectory on the ...

– Mill charge level, optimal ball size, etc. 10. Industrial Case Study Industrial Case Study ––SAG Mill: Status SAG Mill: Status •Mill Diameter : 9.7 m •Mill Speed : 69% C. S. •Power draw Installed : 16.6 MW •Power draw Operating : 15.3 MW •Liner Material : Steel •Number of Lifter Rows : 54 •Lifter Profile : Hi-Hi •Rock F80 Size : 75 mm •Rock Specific Gravity : 2.7 ...

More### Frozen charge detection and automatic loosening with ...

Mill in Brazil and Lumwana having a 38ft, 18 MW SAG and one 26ft, 16 MW Ball Mill in Zambia, all three mills put in operation in 2008, as well as Los Bronces, Confluencia in Chile equipped with one 40ft SAG Mill of 22 MW and two 26ft Ball Mills of 16.4 MW commissioned in 2011. In the light of increasing interest in that technology various further Gearless Mill Drives with FCS are presently ...

More### GrindingExpert™ - WordPress

bearing pressure, mill power, recycle pebbles, mill density, charge toe and mill acoustics, ... Expert System software to signiﬁcantly improve SAG/ball mill performance. MillScanner™ with AID™ (Accurate Impact Detection) is a cutting edge Smart Sensor that rotates with the shell of the mill to display a radial trend of mill sound and vibration energy and identiﬁes charge toe and ...

More### SAG mill ball charge determination and its influence on ...

SAG mill ball charge determination and its influence on mill drive requirements Abstract: In semi-autogenous grinding (SAG), the grinding mill inventory, (i.e. volume of total charge, volume of ball charge, etc.) is important in determining the optimum operating condition for maximum production (tph), minimum specific energy (kwh/t) or lowest cost ($/t). A two-dimensional graphical method is ...

More### How do I track Mill Ball Charge in real-time ...

Navigate to SAG Mill Ball Charge dashboard. Select LIVE mode in the time picker. Observe the Line graph to ensure the ball charge remains within the desired range. See the bar chart to know about the current ball size distribution. Adjust your ball addition schedule as required to achieve the desired ball size distribution. Record the ball addition via the Data Input Widget. See the total ...

More### SAG/AG SCU - Millwatch

Maintaining an optimum charge in a SAG mill remains one of the fundamentals for efficient mill processing. If the charge level or the ball to charge ratio is incorrect, breaking liners and/or increasing power consumption is inevitable and can only result in degraded mill efficiency. To minimize reline time, it is critical to set the charge height at an optimum level. Setting the charge level ...

More### SINGLE STAGE SAG/AG MILLING DESIGN

SAG mill (4% ball charge, 90% Nc) A cross between AG and SAG for average competency, abrasive ores. Typically operated in RSA on Witwatersrand Gold Ore Driefontein (Underground), Kloof, Jacobina 6 SAG mill with recycle crusher (8 – 15% ball charge) Competent ores, better suited to coarse grind sizes. High aspect mills are recommended to provide adequate potential for pebble extraction. St ...

More### Benchmarking: Amelunxen SGI - Agnico Eagle -

SAG mill ball charge = 10.6 % vol; SAG mill discharge % solids = 84% weight; SAG mill speed 8.59 RPM (53.4% of critical) E SAG at mill shell = 1283/210 = 6.11 kWh/t (to achieve DCS power of 1350 kW requires 14% vol mill load) ball mill power draw (sum of 2 mills, at motor input) = 1422 kW (at mill shell = 2 × 674 kW = 1348 kW) ball mill % solids = 83% weight (to achieve 1424 kW, assume 30% ...

More### ERSEL Ağır Makine San. ve Tic. A.Ş.

* Semi-autogenous (SAG) grinding is a grinding process carried out with small amount of ball charge (4-15%) unlike ball mills and with the help of bigger parts crumbling the smaller parts of ore. * To achieve this type of grinding, SAG mills with large diameter and short length have been developed to take advantage of the kinetic energy of the free falling coarse particles. * SAG mills are ...

More### ARE SAG MILLS LOSING MARKET CONFIDENCE?

The use of high ball charge and pebble porting was adopted for increasing the overall performance of the circuit. The project was the first copper operation for Vale and opted for a single SABC line with one 20 MW SAG mill and two 8 MW ball mills, which was supported by analysis of the pilot scale test work. The Sossego plant ramp-up period started in the beginning of 2004 and by the second ...

More### The Effect of the Grinding Charge Trajectory on the ...

– Mill charge level, optimal ball size, etc. 10. Industrial Case Study Industrial Case Study ––SAG Mill: Status SAG Mill: Status •Mill Diameter : 9.7 m •Mill Speed : 69% C. S. •Power draw Installed : 16.6 MW •Power draw Operating : 15.3 MW •Liner Material : Steel •Number of Lifter Rows : 54 •Lifter Profile : Hi-Hi •Rock F80 Size : 75 mm •Rock Specific Gravity : 2.7 ...

More### Flexible milling and grinding solutions that last FLSmidth

For the mining industry, our semi-autogenous (SAG) grinding mill uses a minimal ball charge in the range of 6-15 percent. It is primarily used in the gold, copper and platinum industries as well as in the lead, zinc, silver, and nickel industries. Autogenous (AG) grinding mills involve no grinding media as the ore itself acts as the grinding media. Our ball mills are the most robust design in ...

More### GrindingExpert™ - WordPress

bearing pressure, mill power, recycle pebbles, mill density, charge toe and mill acoustics, ... Expert System software to signiﬁcantly improve SAG/ball mill performance. MillScanner™ with AID™ (Accurate Impact Detection) is a cutting edge Smart Sensor that rotates with the shell of the mill to display a radial trend of mill sound and vibration energy and identiﬁes charge toe and ...

More### SAG mill ball charge determination and its influence on ...

SAG mill ball charge determination and its influence on mill drive requirements Abstract: In semi-autogenous grinding (SAG), the grinding mill inventory, (i.e. volume of total charge, volume of ball charge, etc.) is important in determining the optimum operating condition for maximum production (tph), minimum specific energy (kwh/t) or lowest cost ($/t). A two-dimensional graphical method is ...

More### SAGMILLING.COM .:. tools_millfilling

Enter the number of lifters that are exposed above the mill charge. Fractions are acceptable and should be used in the case where the charge does not sit uniformly in the mill. For example, you may have 29 rows exposed at the discharge end of the mill, and only 28 exposed at the feed end. If so, enter 28.5 for the number of exposed lifters. Calculated Mill Charge: % Calculation backup: The ...

More### SAG/AG SCU - Millwatch

Maintaining an optimum charge in a SAG mill remains one of the fundamentals for efficient mill processing. If the charge level or the ball to charge ratio is incorrect, breaking liners and/or increasing power consumption is inevitable and can only result in degraded mill efficiency. To minimize reline time, it is critical to set the charge height at an optimum level. Setting the charge level ...

More### SINGLE STAGE SAG/AG MILLING DESIGN

SAG mill (4% ball charge, 90% Nc) A cross between AG and SAG for average competency, abrasive ores. Typically operated in RSA on Witwatersrand Gold Ore Driefontein (Underground), Kloof, Jacobina 6 SAG mill with recycle crusher (8 – 15% ball charge) Competent ores, better suited to coarse grind sizes. High aspect mills are recommended to provide adequate potential for pebble extraction. St ...

More### BrainWave: Control solutions for SAG mills

the mill and its ball charge moving, any in - crease in production yields a corresponding reduction in specific energy per ton. What is more, stabilizing the load in the mill also stabilizes power draw. This enables the operator to manage power usage, eliminat - ing the energy waste that comes with a varia - tion in the power draw. The challenge: To control your SAG mill so that it runs at ...

More### SAGMILLING.COM .:. Home

Sagmilling is home to a collection of both free and subscription-based calculation tools to aid metallurgical process engineers perform comminution calculations. Grinding circuit design tools, including for SAG mill-ball mill circuits, and geometallurgy energy models are available to subscribers.

More### [PDF] Discrete Element Method simulation of charge

Discrete Element Method simulation of charge motion in ball, SAG and autogenous mills has become a standard for lifter design, power draft evaluation, etc. Both two-dimensional and three-dimensional codes are being used. The two-dimensional code dominates the user market since the code completes a simulation in one or two hours. On the other hand, three-dimensional codes have been in the ...

More### Frozen charge detection and automatic loosening with ...

Mill in Brazil and Lumwana having a 38ft, 18 MW SAG and one 26ft, 16 MW Ball Mill in Zambia, all three mills put in operation in 2008, as well as Los Bronces, Confluencia in Chile equipped with one 40ft SAG Mill of 22 MW and two 26ft Ball Mills of 16.4 MW commissioned in 2011. In the light of increasing interest in that technology various further Gearless Mill Drives with FCS are presently ...

More### 20150806 Survey Sample Grinding Circuits-GMG-ICE-v01-r02 ...

Grinding (AG), Semi-Autogenous Grinding (SAG), rod, and ball mill circuits operating within the normal range of appli-cation. This guideline does not directly address analysis of crushing plants and fine grinding circuits, but it is a useful reference for such endeavors. Applying power-based analysis techniques requires suf-

More### TECHNICAL NOTES 8 GRINDING R. P. King

The effect of mill charge is primarily through the shifting of the center of gravity and the mass of the charge. As the charge increases the center of gravity moves inward. The power draft is more or less symmetrical about the 50% value. A simple equation for calculating net power draft is P 2.00 3 cD 2.5 m LKl kW (8.12) Kl is the loading factor which can be obtained from Figures 8.5 for the ...

More