SAG Mill Ball Size Evaluator | Evaluation Factors ...

The SAG Mill has a "small" circulation load of oversize given be the 3/8″ trommel screen and the 1/2″ x 1 1/4″ discharge grates. The load of 4″ balls in this SAG is "good" but un-measured. SAG Ball consumption is "average" at 400 g/t while Ball Mill grinding media (3″ balls) usage in 550 g/t.

What's the Difference Between Ball Mill, Rod Mill and SAG ...

Rod mill:The rod mill has the highest efficiency when the feed size is <30mm and the discharge size is about 3mm with uniform particle size and light overcrushing phenomenon. SAG mill: When the weight of the SAG mill is more than 75%, the output is high and the energy consumption is low with a light degree of over-crushing.

Optimizing your SAG mill operation - International Mining

The optimal performance of AG/SAG mills is the key to successful plant operation. All AG/SAG mills using radial or curved pulp lifters suffer from inherent material transport problems such as slurry and pebble pooling, which decrease throughput and increase energy consumption.

BrainWave: Control solutions for SAG mills

control the weight in the SAG mill to promote optimum grinding. This strategy has been demonstrated to improve mill throughput by as much as 3%. When copper prices are high, producers look to increase production by eliminating process bottlenecks. At Minera Los Pelam - bres, as at many mines, SAG mill through - put limits overall production.

OPTIMAL SAG MILL CONTROL USING VIBRATION & DIGITAL …

OPTIMAL SAG MILL CONTROL USING VIBRATION & DIGITAL SIGNAL PROCESSING TECHNIQUES ABSTRACT Recent developments in low power wireless and Digital Signal Processing (DSP) technologies have given rise to a new system that can monitor vibrations in real-time on the rotating surface of SAG, AG, and Ball mills.

Optimization of a SAG Mill Energy System: Integrating Rock ...

An optimization is carried out to minimize the yearly cost of energy for the operation of the SAG mill. This cost includes the energy consumption cost in $/kWh and the capital cost for the PV-BESS infrastructure, prorated over the life of the battery system, accounting for the discount rate through an annuity factor (Pamparana et al. 2019a, b).The energy requirements are defined by the SAG ...

IMPROVING ENERGY EFFICIENCY VIA OPTIMIZED CHARGE …

Depending on the mill size the SAG mills draws between 2 MW and 17 MW. The product from the SAG mill is further reduced in size using pebble crushers and ball mills. Hence, typical gold or copper ore requires between 2.0 and 7.5 kWh per ton of energy to reduce the particle size.

Grinding Media - Growth Steel

APPLICATION ENVIRONMENT For SAG milling applications, the diameter of the balls, mill and throw action of the charge provide for a high impact environment - therefore a balance must be achieved between abrasion resistance and impact resistance in SAG balls to avoid excessive breakage.

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

and optimal grinding charge trajectory for the SAG, Ball and Rod Mills. • Identified potential benefits could be obtained with an ideal grinding media charge, mill speed as well as optimisation of lifter profile (specialty lifter face 20 angle) which is directly related with …

What's the Difference Between Ball Mill, Rod Mill and SAG ...

The biggest characteristic of the sag mill is that the crushing ratio is large. The particle size of the materials to be ground is 300 ~ 400mm, sometimes even larger, and the minimum particle size of the materials to be discharged can reach 0.1 mm. The calculation shows that the crushing ratio can reach 3000 ~ 4000, while the ball mill's ...

(PDF) Understanding the effects of liner wear on SAG mill ...

8 - 9 August 2011 Perth, WA. Fig. 1- Increase in throughput over liner life for a large SAG mill. Unfortunately however, the 32 ft SAG mill that was studi ed for this project does not feature ...

GrindingExpert™ - WordPress

just about SAG mills. Our GrindingExpert™ solutions include ball mill strategies that achieve the target grind size while maximizing throughput, or when the circuit is SAG mill limited, achieve the finest grind size possible, thus increasing mineral liberation and recovery. GrindingExpert™ has been shown to typically increase throughput by ...

Grinding Mill Computer Model

is derived from the power required to maintain mill revolutions with the mass of charge acting at the centroid of the mass. This is a form of equation used by many ... Optimum Feed Size for ball mills F Wb =4 000 13,* MILLCALCv2a 7 19/02/2004. ... size and power relationships For SAG mills the equation becomes Power= ...

SAG Mill | Autogenous and Semi-Autogenous Mills | …

Since the early 1980s, we have been designing and manufacturing Semi Autogenous Mill (SAG Mill) and Autogenous Mill (AG Mill) under the Fuller-Traylor brand. Semi-autogenous grinding uses a minimal ball charge in the range of 6-15% while autogenous grinding uses ore only. SAG and AG Mills operate by lifting ore/grinding media and dropping it on ...

Mill Charge - an overview | ScienceDirect Topics

According to available literature, the operating speeds of AG mills are much higher than conventional tumbling mills and are in the range of 80–85% of the critical speed. SAG mills of comparable size but containing say 10% ball charge (in addition to the rocks), normally, operate between 70 …

Optimal Speed Control for a Semi-Autogenous Mill Based on ...

In this study, the relationship between the optimal speed and the size and number of particles in the SAG mill was mainly investigated based on discrete element method. For optimal speed control, an improved sliding mode control of the exponential approaching law is proposed to improve the stability and rapidity of sliding mode control near the ...

Optimize SAG milling with customised grinding ball design ...

The sheer size and scale of new ore processing operations, with their associated desire to substantially increase product throughput, means that primary SAG mills have grown to larger capacities. Paul Peng, CEO and chief metallurgist at Sino Grinding Industries (SGI), emphasizes it is critical that grinding media is designed and manufactured to cope with this […]

Autogenous and Semi-Autogenous Mills - ScienceDirect

The SAG mill had a 6–8% ball charge and the power consumption was 8 kWh/t, which agreed well with the expected value. 9.6. Problems. 9.1. In an SAG mill the dimensions of the mill were 9.75 m × 3.5 m and the specific gravities of the mineral and …

Feed size for sag mill - Desle Mining Machinery

The optimum feed size for the rod mill oversize feed factor (EF 4 RM) in the Barratt E SAG equation is calculated using the greater of the sample's rod mill or crushing work index. The EF 4 RM is calculated greater of the crushing work index or the rod mill work index. The ball mill oversize feed factor (EF 4 BM) is always calculated with the

sag mill optimum charge size - razoriteolivedale.co.za

SAG mill ball charge determination and its influence on ... May 24, 1990· 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).

(PDF) SAG mill circuit optimisation at Ernest Henry Mining

At 8 – 12 % v/v ball charge volume, and 25 – 35% v/v total charge volume the SAG mill typically draws 10 –. 11 MW. The operating work index for the mill is extremely ore. depe ndent and can ...

Optimum choice of the make-up ball sizes for maximum ...

The minimum ball size in the charge was taken as 12.7 ... 11 shows the results of the grinding of a feed of various sizes at a size reduction ratio of 45:1 using a 1 m diameter mill. It can be seen that the optimum portion of the 50.8 ...

Types Of Charges In Sag Mill

types of charges in sag mill benb-bennekom.nl. The SAG mill had a 6–8% ball charge and the power consumption was 8 kWh/t, which agreed well with the expected value. 9.6. Problems. 9.1. In an SAG mill the dimensions of the mill were 9.75 m × 3.5 m and the specific gravities of the mineral and that of the balls charged were 4.1 and 7.9 ...

How To Calculate Mill Charge Level

optimisation of the cadia hill sag mill circuit abstract ... - . Figure 1: Concentrator Throughput and Availability Project to Date. SAG mill .... occurred. SAG mill speed was thus lowered and charge level raised until. Read more

PERI™ AutoCharge Mill Grinding Ball Charging System

The AutoCharge system is primarily suitable for SAG mill balls (100–150 mm). As each ball rolls through the counting chute, an electro-mechanical limit switch is activated, signalling the counter. Each count is added to the last, allowing a continual increasing total count …

PARAMETER OPTIMIZATION OF LARGE SAG MILL LINER BASED …

Due to its strong lifting capacity and excellent grinding performance, the trapezoidal liner is widely used in the SAG mill. The structure of the trapezoidal liner is shown in Fig. 1, the main dimensions are: dip angle (tau), length of the top edge (L) and height (h).Dip angle (tau) determines the trajectory of the mediums in the SAG mill, which directly affects the impact speed and ...

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

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 presented for determining the actual ball charge within the total charge when …

TECHNICAL NOTES 8 GRINDING R. P. King

LG A mill power equation for SAG mills. Minerals and Metallurgical Processing. Feb 1990 pp57-62. Gross power No load power Net power drawn by the charge (8.13) The net power is calculated from Net power KD2.5L e! c./ Watts (8.14) In equation 8.14, D is the diameter inside the mill liners and Le is the effective length of the mill including the ...

The influence of mill speed and pulp density on the ...

mill with a 30 mm graded ball charge and a 30% filling degree. The mill discharge pulp density was increased from 68.8% to 75.9% solids. The data is summarized in Table III. The example in Table III illustrates that the density has a large influence on the grinding efficiency. In this case, the optimum %<75 µis in the region of 73.4% or 1.989 kg/l

AMIT 135: Lesson 6 Grinding Circuit – Mining Mill Operator ...

The mill product can either be finished size ready for processing, or an intermediate size ready for final grinding in a rod mill, ball mill or pebble mill. AG/SAG mills can accomplish the same size reduction work as two or three stages of crushing and screening, a rod mill, and some or all of the work of a ball mill. Because of the range of ...