The feed size distribution together with the ore characteristics (hardness, lithology, alterations, etc.) are the most important factors affecting the SAG mills performance.
1 IMPROVEMENTS IN SAG MILL THROUGHPUT FROM FINER FEED SIZE AT THE NEWMONT AHAFO OPERATION *Adrian Dance1, Sonny Mwansa2, Walter Valery 2, George Amonoo3 and Bryon Bisiaux3 1SRK Consulting (Canada) Inc 22nd Floor, 1066 West
SAG is an acronym for semi-autogenous grinding. SAG mills are autogenous mills that also use grinding balls like a ball mill. A SAG mill is usually a primary or first stage grinder. SAG mills use a ball charge of 8 to 21%. The largest SAG mill is 42' (12.8m) in diameter, powered by a 28 MW (38,000 HP) motor.
Feed size effects what size is important? historically, Mine-to-Mill has focussed on blasting alone generation of more fines • pass through SAG mill onto ball mill circuits • higher throughput (e.g. 10% to 30%) • coarser grind size (possibly) fine <25mm medium 25 75mm coarse >75mm
We describe here one of the very first pioneering SAG Mill Feed Particle Size Analysers: A set of preliminary experiments was carried out in order to assess the hardware-software’s behaviour. Static ore was used to obtain the right sequence of image processing algorithms. The camera was installed 3 mts away from the commercial sizer over the feed conveyor of the SAG Mill.
Secondary mill feed Continuous regulation capability gate to allow controlled distribution of feed between the two ball mills. Finally, if the amount of critical size material removed from the mill is less than the crusher and secondary mills capacities, those mills can also be fed with a small fraction of the SAG mill trommel undersize in order to take full advantage of their installed power.
xG is the mill feed d80, not the circuit feed. For SAG mill, the xG value has to be determined by scalping of the full size distribution. The particles larger than the minimum pebble size (given by the pebble extraction grate opening) has to be excluded from the distribution to calculate the top ball size!
Secondary mill feed Continuous regulation capability gate to allow controlled distribution of feed between the two ball mills. Finally, if the amount of critical size material removed from the mill is less than the crusher and secondary mills capacities, those mills can also be fed with a small fraction of the SAG mill trommel undersize in order to take full advantage of their installed power.
will become the predictions. In the case of SAB/SABC circuits the transfer size is the product of the SAG mill circuit and the feed of the ball mill circuit. Hence if power-based equations such as
I-203 INFLUENCE OF FEED SIZE ON AG/SAG MILL PERFORMANCE S.Morrell1 & W.Valery 1 1.JKMRC, Isles Road, Indooroopilly, Qld 4068, Australia e-mail : [email protected]
The capacity of the SAG mill is related to lots of factors such as feed size, size distribution, discharge size and grindability, etc., and it should be confirmed according to the actual situation. SM40*14’——means it is a dry mill.
stage ball mills, rod mills or AG/SAG mills when calculating power according to the Bond Third Theory method. Rod mill and AG/SAG mill products are similar and tend to be not as steep as a 0.5 slope when plotted on log-log paper. This is because the particle size distribution (PSD), these mills
O I SKARIN N O TIKHONOV CALCULATION OF THE,the required SAG comminution of test ore material Specific energy consumption (SEC) measured in kWh/t is a ratio of the mill drive power to the milling circuit output, without regard to circulating load At the constant size of the cycle feed and discharge, SEC is a prime characteristic of material grindability in a certain ore pretreatment .
Feed Size, F80: Primary crushed ore is mandatory to feed any SAG mill. Typical feed size range is 80% passing 130 to 160 mm. Softer ores will be a little finer but the finer size is not sustainable when the ore becomes hard. Pre-crushing to finer sizes enhances throughput as does crushing of pebbles from the SAG mill (usually minus 60 mm).
respect with SAG mills being increasingly less sensitive as the ball charge is increased (Morrel S and Valery W, 2001). 2.2. EFFECT OF FEED SIZE DISTRIBUTION ON SAG MILLING The qualitative eﬀect of changes in particle size distributions (PSD) on the SAG mill performance can be addressed by using the grind curves. The operation of SAG mills is
Choosing a SAG Mill To Achieve Design Performance John Starkey1, Principal Consulting Engineer Sami Hindstrom2, Manager, Grinding Travis Orser2, Project Manager, Grinding 1 Starkey & Associates Grinding Design and Process Engineering 336 268 Lakeshore Rd. E. Oakville, Ontario L6J 7S4
The oversize material is recycled to the SAG mill feed via conveyors and the undersize material is combined in the cyclone feed sump with the ball mill discharge and feed to the ball mill classifying cyclones. Product overflow from the cyclones is gravity fed to subsequent flotation processes and the underflow is feed to the ball mill.
Choosing a SAG Mill To Achieve Design Performance John Starkey1, Principal Consulting Engineer Sami Hindstrom2, Manager, Grinding Travis Orser2, Project Manager, Grinding 1 Starkey & Associates Grinding Design and Process Engineering 336 268 Lakeshore Rd. E. Oakville, Ontario L6J 7S4
Modelling SAG milling power and speciﬁc energy consumption including the feed percentage of intermediate size particles M. Silva, A. Casali⇑ Mining Engineering Department, Universidad de Chile, Beauchef 850, Santiago 8370448, Chile
grinding, to single stage crushing and semi-autogenous grinding (SAG) and ball mill (SAB) circuits. This progression has, not necessarily, been accompanied by an improvement in the efficiency of power utilisation in achieving the target grind size, but has seen an improvement in the overall efficiency of mineral processing as measured by the overall cost of grinding to the required size for
The outcome of the crushing circuit improvements was a finer feed size to the SAG mill on Wallaby Deeps underground ore. SAG mill feed size distributions from samples collected in late 2011 (before screen changes) and early 2012 (after changes) are shown in Figure 3.
We offer autogenous (AG), semi-autogenous (SAG), ball, rod, and pebble mills in sizes ranging from kWs up to 30+ MW. Our product range also includes a number of unique solutions, including the world’s largest acid-resistant grinding mills, which can operate with extremely corrosive slurry.
Ø SAG mill availability was lower than expected in the first year due to issues with the gearless drive and trommel panel failures. Figure 1 shows the ramp up of the Cadia Hill SAG mill by quarter.
In these circuits the SAG mill is the largest energy consumer. In many engineering projects either a power equation and/or a specific energy equation are used for the designing of these mills but not always with acceptable results. In general these equations are used to predict power consumption as a function of mill size, level and density of
The DWi has also been found to be correlated to the point load index and UCS, which makes it valuable for predicting AG/SAG mill feed size as well as conducting Mine-to-Mill projects. It is also
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 SAG mill is about 9% to 20%.This process takes place inside the large rotating drum of SAG mill which is filled with balls partially. Interior of
SINGLE STAGE SAG/AG MILLING DESIGN ABSTRACT Single stage semi-autogenous / autogenous (S/AG) milling has become a common design for a variety of ore types with the advantages of being comparatively low capital cost and flexible for future expansion. The single stage
Every mining operation has a unique grinding process. liming has experience of over 8,000 grinding mills globally, including manufacturing and delivering the largest SAG/AG mills in the world. Our experts welcome the opportunity to assist you with circuit and circuit control design as well as start-up, operation, and optimization of your mill.
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 (e.g., smaller than 12mm) that will pass through the primary mills and onto the secondary ball mill circuits, alleviating a common bottleneck.
The SAG Mill is a block added by the EnderIO mod. A machine similar to a Pulverizer or a Macerator. It is used to process resources to produce dust. It accepts energy in the form of Redstone Flux or Minecraft Joule, with an internal buffer of 100,000 RF and consumption of 20 RF per tick.
27/03/2015· A Rocky DEM simulation of a SAG mill feed showing size segregation (Brazilian Nut effect). For more information about Rocky DEM Particle Simulation software,...
Autogenous and Semi-Autogenous Mills The optimum solution for wet grinding. 2 AG/AG Mills AG/AG Mills 3 liming’s AG/SAG mills accomplish the same size reduction work as 2 or 3 stages of crushing and screening The feed size for these mills is limited to the maximum size that can be practically conveyed and introduced into the large mill feed chutes. And the product of the large AG/SAG grinding
or stopping the SAG mill. Feed System Control Crushed ore is fed onto the feed conveyor using one or more variable speed feeders. The feeders are located under the ore stockpile or bins. By running different feeder combinations the size distribution of the SAG mill feed can
Ball Mill Product Size, P80, microns Feed Size, F80, mm Transfer Size, T80, microns Ore SG Ball Mill Grindability, kWh/ton Average No ENERGY REQUIREMENTS CALCULATION: Pebble Crusher, Y/N From SAGDesign testwork results. Notes Ball Mill Reduction Ratio, RR Inefficiency for coarser feed to ball mill Inefficiency for finer final product size Efficiency for BM diameter other than 8 ft MILL PINION
SAG mill feed size distribution manipulation and optimization. Question: In our Gold Plant we have 2 SAG (tubular 24x16 feet) mills operating in parrallel in closed circuit with hydrocylones, the mill feed size is 170mm and flactuates up to 200mm (crusher gap).In an initiative to increase throughput one of the option is to have a pre crusher to reduce feed size distribution and have a
Morrell Mi (SMC) single-Stage SAG Mill Model. This is a SAG or AG mill model that estimates the specific energy consumption (E SAG) using the equations of Morrell (2004). Testwork Required. The SMC™ test, stored in the "DWT" testwork table (SMC is a Drop Weight Test). Bond ball mill work index.
The Outotec ACT grinding optimization system utilizes feed particle size data from RockSense, charge analysis from MillSense, and slurry particle size measurements from PSI, as well as other available on-line measurements. Figure 1. Outotec’s ACT grinding optimization system with RockSense, MillSense, and PSI particle size analyzer gives you