(PDF) Design of the biggest mill in the world
Maximum SAG mill po wer was determined by deducting the install ed ball mill pinion power of 7.95kWh/t (16,400kW) from the maximum overall circuit power of 16.7kWh/t to …
Improving Energy Efficiency Via Optimized Charge Motion ...
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 …
to Design and Supply the World's Largest SAG Mill in ...
has been selected to design and supply a 42ft x 25ft, (12.8m x 7.6m) 28MW gearless SAG mill, plus two 26ft x 42ft, (7.9m x 12.8m) 15.6MW ball mills and two VTM-1500-WB VERTIMILLS® for Newmont Mining's Yanacocha Conga copper-gold project in Peru. The 42ft diameter SAG mill is the world's largest and the first of its kind.
introduction of several industry mills--Thanks To Visit
SAG mills are essentially autogenous mills, but utilize grinding balls to aid in grinding like in a ball mill. A SAG mill is generally used as a primary or first stage grinding solution. The SAG mills use a minimal ball charge of 6 to 15%. SAG mills can be as large as 42' in diameter, with up to a 28 MW (37549 HP) motor.
Difference Between Sag Mill vs Ball Mill - mech4study
A horizontal or vertical rotating cylinder which is filled partially with the balls of ceramics, small rocks and balls made from stainless steel. The ball charge of a SAG mill is about 29% to 30%. By friction and influence of tumbling balls inside rotating cylinder grinds the raw material to the required fineness.
White paper, September 2015 SmartMill™: Exceed your ...
small charge of steel balls may be added to aid the process — the mill is then called a semi-autogenous (SAG) mill. AG/SAG mills are often used as the first stage in a two- or multiple-stage grinding process, where the second stage is carried out by the ball mill, but they can also be used as a one-stage grinder. The absence of, or
AMIT 135: Lesson 6 Grinding Circuit – Mining Mill Operator ...
SAG Mill Circuit Example — Gold Processing SAG mill circuit example for gold processing [image: (135-6-3)] AG/SAG Mill. AG/SAG mills are normally used to grind run-off-mine ore or primary crusher product. Wet grinding in an AG/SAG mill is accomplished in a slurry of 50 to 80 percent solids. 2D and 3D simulations of particles in a SAG Mill
C O N S U L T I N G L T D TECHNICAL MEMORANDUM
EF5BM=[ P80+10.3 1.145×P80] ( 3 ) The EF4 formula requires both the rod mill and ball mill work index (rod mill Wi is used to calculate the optimal feed size) and because this is a "single-stage ball mill" calculation, the F80 is actually the rod mill feed size (10,000 µm) from Table 1 and the P80 is the ball mill circuit product. The EF5 factor only applies below 75 µm to ball
INFERENTIAL MEASUREMENT OF SAG MILL PARAMETERS IV ...
The SAG mill rock charge properties (SMRC) and size distribution (smrc) ... (12), as inequality constraints. The ball charge must be less than or equal to the total charge: J b d J t (12) For the powerdraw residual, F kW [kW], see Equation (13), the charge fractions are determined to equate the calculated powerdraw solution, P
Integrated drive technology from Siemens enhances ...
In future, two gearless mill drives and Sinamics cycloconverters will be used in the new production line with one SAG mill and one ball mill. Thus, one million tons of copper concentrate, 10 000 tons of molybdenum and four million ounces of silver oxide can be mined annually – even at an altitude of around 4600 m above mean sea level.
AN UPDATED DATA SET FOR SAG MILL POWER MODEL …
SAG mill power draw models are used in mill design and grinding circuit modelling to predict ... by the balls within the mill charge, as would be measured in a mill grind-out. ... and it must be converted to the same basis as the Austin model (mill shell basis) to perform meaningful comparisons. ...
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 …
Charge Motion inside a SAG Mill - 911metallurgist
Charge Motion inside a SAG Mill. For proper design of SAG mills and other types of grinding mills, the operating conditions have to be defined. Predicting the composition of the SAG mill charge is a difficult task since a number of significant phenomena associated with the charge motion must be taken into consideration.
Gearless Mill Drives | Beneficiation | Siemens Global
Frozen charge detection and automatic loosening with gearless mill drives (SAG Conf. 2015) Mill drives: the desire for increased power and the associated limits and conditions (SAG Conf. 2015) The engineering and process effects of choosing a motor design speed (SAG Conf. 2015)
SAG mill ball charge determination and its influence on ...
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 …
Key considerations when selecting a mill lining system
To achieve this, the mill liner profile must be constructed from high wear resistant materials and incorporate correct geometry to help determine the elevation of the mill charge and how the material is ground. A comparison of SAG and ball mill charge actions is shown below.
What is the difference between a SAG mill and ball mill?
A SAG mill is usually a primary or first stage grinder. SAG mills use a ball charge of 8 to 21%.[6][7] The largest SAG mill is 42′ (12.8m) in diameter, powered by a 28 MW (38,000 HP) motor.[8] A SAG mill with a 44′ (13.4m) diameter and a …
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.
(PDF) Power Draw of Grinding Mills - its Measurement and ...
The formulations incorporate novel models of the SAG mill ball charge, protective shell lining, mill weight measurement and discharge measurement. ...
A mill power equation for SAG mills | SpringerLink
where m p is in kW; D is internal mill diameter (meters), L is internal mill length (meters); J is total fractional charge loading of the mill; J B is the fractional mill filling by balls; ε B is the effective porosity of the charge, taken as 0.3; ρ s and ρ b are true densities of rock and balls (tons per cubic meter), respectively; w c is the weight fraction of rock in water and rock in ...
Ring-geared mill drives - Grinding | ABB
Mill application features. Frozen charge protection – Detects frozen charge in the mill, minimizing equipment wear and liner replacements.; Coupling supervision – Detects if a failure or slippage occurs in the couplings and stops the system in case, preventing major damages.; Stand-still detection – Prevents the motors from re-starting if the mill is still rocking or moving …
(PDF) Influence of feed size on AG / SAG mill performance
with sag mills being increasingly less so as the ball charge is increased. ... to the stockpile must be treated through the ag/sag mill. Hence for ... When the feed size of a SAG mill becomes ...
SAGMILLING .:. 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.
AG - Autogenous & SAG Semi-Autogenous Mill Design …
Current operational results show that the SAG mill is operating at 5% ball charge level by volume and is delivering a K80 800 micron product as predicted.
Simple SAG Mill - Official Feed The Beast Wiki
The Simple SAG Mill is a machine added by Ender IO. It uses Micro Infinity (µI) to grind (or mill) items into their crushed variants, like Ores into Dusts. The Simple SAG Mill has four output slots; recipes can have 1-4 different outputs, with different chances of obtaining those outputs. Similar to Ender IO's other Simple machines, capacitors cannot be used in the Simple SAG Mill, so its ...
Semi-autogenous grinding (SAG) mill liner design and ...
objectives in SAG mill shell lifter design are: • to provide the key between the mill charge and the mill shell for charge motion, • to maximize the rate of delivery of thrown grinding media at the toe of the charge to gain the best milling action, • to avoid liner and ball damage and • to provide an economic liner wear life.
Development of a method to measure charges in tumbling mills
The charge level of a mill can be described as the volume occupied by the grinding media (including empty spaces) as a fraction of the total volume available inside the equipment. Assuming this definition, other measurements may be taken considering the total charge that includes the rock charge; in this case, applicable to SAG and AG mills.
SAG Mill - Official Feed The Beast Wiki
The SAG Mill is a machine added by Ender IO.It uses Micro Infinity (µI) to grind (or mill) items into their crushed variants, like Ores into Dusts.The SAG Mill has four output slots; recipes can have 1-4 different outputs, with different chances of obtaining those outputs. Uniquely, the SAG Mill can use Grinding Balls made from various materials to increase energy efficiency …
how to calculate mill charge level
how to calculate ball sag mill charge level calculating steel ball level in sag mill Difference Between Sag Mill vs Ball Mill mech4study 12 10 2017 SAG mill make use of steel balls included with some large and hard rocks for grinding These mills utilize the balls in making the large fragments of materials broken into pieces The ball charge of a ...
Grinding circuit for Mount Milligan mine | ABB
As a result, ABB could provide a fully integrated and optimized solution for the entire grinding circuit consisting of: 1 x 23.5 MW gearless mill drive system (GMD) to power the 40 ft SAG mill. 2 x 13 MW low-speed dual pinion ring-geared mill drive systems (RMD) to power the plant's 26 ft ball mills. Both drive solutions share many common ...
AN OVERVIEW OF SINGLE STAGE AUTOGENOUS AND …
3 SAG mill (8 – 15% ball charge) Variable competency ore 4 High ball charge SAG mill (15 to 25% ball charge) Incompetent ore 5 Low ball charge SAG mill, high mill speed. (4% ball charge, 90% Nc) A cross between AG and SAG for competent, abrasive ores. As typically operated in RSA. 6 SAG mill (configurations 3, and 5 ) with recycle crusher
Grinding Circuit - an overview | ScienceDirect Topics
SAG mill product feeds two parallel ball mills of 6.6 m×11.1 m (internal diameter×length), each with a 9.7 MW twin pinion drive. The ball mills are operated at a ball charge volume of 30–32% and 78.5% critical speed. The SAG mill trommel undersize is combined with the ball mills' discharge and pumped to two parallel packs (clusters) of ...