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
how to calculate sag mill ball charge - BINQ Mining
how to calculate motor kw of ball mill – Grinding Mill China Tubular Ball Mills – Free download as PDF File (pdf), text file (txt) or read online for free » Free Online Chat , how to calculate sag mill ball charge »More detailed
Improved Relationships for Discharge in SAG/AG Mills
The literature exposed a clear lack of previous research on the influence and performance of grate/pulp lifter design in AG/SAG mill discharge The current understanding from literature lacks knowledge of mill content size distribution and its effect on discharge through the ,
A Method to Determine the Ball Filling, in Miduk Copper ,
was to locate the variation of ball filling in the mill Ball Charge Program Abrasion In this section, ball abrasion was calculated via manufacture`s ball charge program At the time of this research, mill ball charged, feed rate, and average moisture were 7 tons (ball size was 100 ,
Semi-autogenous grinding (SAG) mill liner design and ,
critical to good mill performance The important process 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
STARTLING EFFECT OF BALL SCATS REMOVAL ON SAG MILL ,
STARTLING EFFECT OF BALL SCATS REMOVAL ON SAG MILL PERFORMANCE Malcolm Powell Head Comminution Group, Mineral Processing Research Unit, , the ball scats from a single-stage SAG mill These scats are non- , This work highlights the importance of maintaining a competent ball charge in a mill
TECHNICAL NOTES 8 GRINDING R P King - Mineral Tech
TECHNICAL NOTES 8 GRINDING R P King 8-2 &ROOLVLRQ , The effect of mill charge is primarily through the shifting of the center of gravity and the mass of the charge As the , steel balls in a ball mill, or large lumps of ore in an autogenous mill or a mixture in a semi-autogenous mill.
IV-124 STARTLING EFFECT OF BALL SCATS REMOVAL ON SAG MILL ,
Abstract An increase of over 10 % in mill throughput was achieved by removing the ball scats from a single-stage SAG mill These scats are non-spherical ball fragments resulting from uneven wear of balls with included porosity 30t of scats were removed from a total charge load of 70t
Modelling SAG milling power and speciﬁc energy consumption including the feed percentage of intermediate size particles , that the feed particle size has on the mill performance, particularly on the power and on the speciﬁc , Scw = solid concentration by weight fraction in the SAG mill feed; Jb = balls charge (bulk fraction of the SAG .
Ball and ore particles follow Newton's laws of motion 1 A mill speed approaching 80% of critical can optimize grinding action and reduce wear A charge with a increased trajectory does less work and more damage as grinding balls are flung against the opposite side of the shell instead of falling down on top of the central mass 2
A method to predict shape and trajectory of charge in ,
The effect of charge, which is essentially exerting additional force to the outermost layer of charge, increases where there is no support to keep the balls in contact with mill shell As the face angle decreases the effect of charge decreases because the liner could to some extent keep the balls ,
Optimizing Performance of SABC Comminution Circuit of ,
Optimizing Performance of SABC Comminution Circuit of the Wushan Porphyry Copper Mine—A Practical Approach , circuit included an increase in the SAG mill ball charge from 8% to 10% v/v; an increase in the mill ball , the SAG mill and ball mill was 8658 kW, which caused partial over-grinding From experience in
The influence of mill speed and pulp density on the ,
mill weight during the test from the empty mill weight, including the ball charge, at the start of the test The pulp , LUX, J and CLERMONT, B The influence of mill speed and pulp density on the grinding efficiency for secondary stage grinding International Platinum , does not have any effect and does not result in a finer grind
Application of Operating Work Indices in Autogenous ,
work indices for the AG/SAG mill and ball mill can be re-organised as  and , where B’Wio and A’Wio are the corrected operating work indices and WAG/SAG, WBM are the respective power draw of AG/SAG and ball mills Note that the ball mill operating work index is applied only on the portion that needs the additional grinding (Q2).
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
Grinding Mill Charge Detection Sensors The throughput and efficiency of a SAG mill depends on the volumetric load: An overloaded mill has reduced coarse ore breakage, as the cascading balls and rock cannot drop far enough, reducing kinetic energy for breakage
difference between sag mill and ball mill | Solution for ,
Oct 22, 2012· scenario the performance optimization of typically large SAG Mill/Ball Mills plants has become a weighty item to make projects viable A method to optimize the SAG Mill , SME 2009 Impact on Grinding Mill Design and Recent New Discoveri between SAG and ball mills at the design T80 (transfer , the ratio of SAG kWh/t to Bond Ball Mill Wi
, time of grinding, speed (rpm) of the ball mill , increase with respect to the overall effect of increase in , jar at about 60 revolutions per minute , » More detailed Mechanochemical effect of talc during fine grinding process in a ,
Continuous Monitoring of Mineral Processes with Special ,
Mill charge features such as toe and shoulder position of the charge are well marked However, DEM prediction shows lower values compared to measurements which is most likely an effect of the two- dimensional model used and the inability to model the effect of slurry present in the mill
Jan 08, 2016· In this training module, we'll cover the workings of a semi-autogenous grinding mill, or SAG mill, that's designed to be the first stage of a grinding circuit Ore that’s crushed in a primary .
Ball Size as Initial Charge Commercial ball sizes 10 – 150 mm; Number, size and mass of each ball size depends on mill load and whether or not the media is being added as the initial charge For the initial chargin of a mill, Coghill and DeVaney (1937) defined the ball size as a function of the top size of the feed, ie, d↓V = 040 K√F
Optimum choice of the make-up ball sizes for maximum ,
It is possible then to incorporate this information into a grinding model and investigate the effect of the make-up ball size on the mill performance with various feed and product specifications Concha et al was the first to combine a grinding circuit model with a ball wear model to optimize the make-up ball charge With an optimization .
Performance enhancement tools for grinding mills - SAIMM
PERFORMANCE ENHANCMENT TOOLS FOR GRINDING MILLS 103 The need for new instruments , SAG and ball mills have grown in size and there are now many operational mills in the range of 28–40 feet in , Effect of mill speed and lifter profile on load trajectors Figure 2 Schematic view of ball ,
-BWI = Bond ball mill work index on SAG ground ore, kWh/ton ground F 80 = 80% passing of SAG ground of the test feed size, microns P 80 = 80% passing from the test product size, microns P cs = Bond closing screen size, microns G pb = Ball mill grindability (average of last three cycles), gr/rev Determination of the SAG and Ball Mill Pinion Energy :
A ball mill, a type of grinder, is a cylindrical device used in grinding (or mixing) materials like ores, chemicals, ceramic raw materials and paintsBall mills rotate around a horizontal axis, partially filled with the material to be ground plus the grinding medium Different materials are used as media, including ceramic balls, flint pebbles and stainless steel balls
Performance Studies On SAG Mill In The , - onemineorg
Semi-autogenous (SAG) mill performance is influenced by ball charge, feed properties, shell, grate, and pulp lifter design In the performance study of SAG mill, based on the results obtained it can be observed that SAG mill performed better at feed size +4 inch ,
Mining comminution – crusher, ball mill, and advanced ,
To get optimal performance from your rock crusher, ball mill and all oth When people think of mineral processing and comminution, they tend to focus on equipment like the SAG mill To get optimal performance from your rock crusher, ball mill and all oth , Even the SAG ball charge needs to be adjusted based on the size and hardness of ore it .
Mine-to-mill optimisation: effect of feed size on mill throughput No 48 SRK Consulting’s International Newsletter One of the most valuable aspects of blasting is the generation of very fine particles (eg, smaller than 12mm) that will pass through the primary mills and onto the secondary ball mill circuits, alleviating a common bottleneck