In order to obtain the optimal operation parameters of a SAG mill, in this paper, the discrete element method (DEM) is used to simulate the breakage process of the particles by controlling three parameters, i.e., the mill speed ratio, the mill fill level ratio, and the steel ball ratio. This method simulates the particles size, mill power, and ...
In order to obtain the optimal operation parameters of a SAG mill, in this paper, the discrete element method (DEM) is used to simulate the breakage process of …
The new method offers engineers and researchers a safer and faster method for quantifying the filling level in industrial SAG and ball mills, and allows the surface …
Single stage SAG Mills are very beneficial in reducing CAPEX for plants with a staged throughput approach. When future tonnage is to be increased, the SAG Mill can feed downstream ball milling to boost capacity. Fuller-Traylor SAG/AG Mills range in size from 4.3m through 12.2m in diameter with powers as high as 28,000 kW.
one SAG mill (9.75 dia.(m)*3.88 length(m)) following two parallel ball mills (5dia.(m)*7lenght(m)). The aim of this research work was to investigate on the ball filling estimation of Miduk semi-autogenous (SAG) Mill via an utilized method. Miduk SAG Mill circuit is shown in Figure 1. Figure 1: Diagram of Miduk Copper Complex
In order to obtain the optimal operation parameters of a SAG mill, in this paper, the discrete element method (DEM) is used to simulate the breakage process of the particles by …
NAVACHAB CIRCUIT. The circuit consists of a single-stage, low aspect ratio (diameter:length = 0.5) mill, typical of the majority of SAG mills in the South African gold mining industry. These are locally known as run-of-mine, RoM, mills. The mill is operated at 90% of critical speed and with a volumetric load of 40%.
Greatly accelerated liner wear due to high-energy impacts on the liner. For a 5m diameter mill these will be in excess of 8m.s-1, for a 10m diameter mill these exceed 12m.s-1. This causes high chrome liners to spall and crack and they may even fracture. This can reduce liner life from a year to less than a few months.
A linkedin group was recently discussing this by asking: I've tried to estimate AG/SAG Mill power requirements using several different methods: (1) Using the results of SMC data. (2) Using SAG Power Index (SPI) data. (3) Using the 1989 Barratt method updated on Alex Doll's Web site (February 16, 2015)
It is an approximation or a best guess based on limited data. This equation is: y = 225 – 1.94 x (1) Where x = the load in the mill expressed as measured % by volume …
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. Power drawn at the pinion is 448 kW, 13.617 kWh/tonne (SAG mill) and 570 kW, 17.325 kWh/tonne (ball mill) when processing 32.9 mtph, for a total of 30.942 kWh/tonne or …
The new method offers engineers and researchers a safer and faster method for quantifying the filling level in industrial SAG and ball mills, and allows the surface profile to be surveyed, without requiring the contents to be level. ... a complete grind-out to quantify the volume of steel balls contained in the mill. While the mill contents can ...
Mishra and Rajamani [[2], [3], [4]] first studied the charging behavior and the rule of energy consumption of the ball mill based on 2D DEM in 1992. Cleary et al. [5] studied the effect of ball mill rotational rate on charge behavior and mill power, and in 2001, Cleary et al. [6] first applied 3D DEM to calculate the operating power of a SAG mill.
Ball feed size SAG mill water flow rate SAG mill power vs. wear geometry - maximizing kW-hr/ton & tons/hour in combination SAG mill liner change-out life/cycle vs. tons/kg consumed. Ball mill liner efficiency based on liner geometry and its influence on kW-hours/ton, total tons/life cycle, and P80 transfer to cyclones. Ball mill grind is based ...
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 …
This paper presents three methods using the Morrell C-model to estimate total and ball charge volumes for SAG mills, depending on the data and measurements …
The ball charge and ore charge volume is a variable, subject to what is the target for that operation. The type of mill also is a factor as if it is an overflow mill (subject to the diameter of the discharge port) is usually up to about 40-45%. If it is a grate discharge you will have more flexibility of the total charge.
For the ball mill efficient operation, it is necessary to constantly maintain the required loading level by the grinding media. ... If you need the calculation of the filling degree the ball mill with grinding media, our technical experts will help you as soon as possible. ... 44 Antonovycha str., of. 57, 03150 Kyiv, Ukraine Skype: energo.steel ...
Just published is some Newmont data in a paper at SAG 2011 on both SAG and ball mill steel consumption. The ball mill wear data reflected a 0.5 factor on the Bond equation consistent with Arts observation above. I also like the Molycop equation Levi has discussed for ball mills although it does seem to reflect slightly higher wear rates than ...
Gross power = 265 + 1.26 × (2,233 + 215) = 3,349 kW. The conversion between motor input (gross) power and mill shell power, described earlier, is 0.931. Therefore, the predicted power at the mill shell is 3,119 kW, which is 71 kW less than the measured shell power (3,190 kW), a difference of 2%.
Same with the experiment (Banisi & Hadizadeh, 2007), the rotation speed of mill is 10.5 rpm, which is 77% of the critical rotation speed.The ore filling level is 20% (ψ ore = 20%), which contains about 0.4 million ore particles; the media filling level is 15% (ψ media = 15%), which contains 3285 steel balls.It should be noted that the filling level in …
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. Power drawn at the pinion is 448 kW, 13.617 kWh/tonne (SAG mill) and 570 kW, 17.325 kWh/tonne (ball mill) when processing 32.9 mtph, for a total of 30.942 kWh/tonne or 14.6% above the ...
In this paper, the optimal fracture parameters of the SAG mill are 80% rotation rate, 15% fill level ratio, and 14% steel ball ratio, and through subsequent simulation experiments, the steel ball ratio of the …
Ball mills are extensively used in the size reduction process of different ores and minerals. The fill level inside a ball mill is a crucial parameter which needs to be monitored regularly for optimal operation of the ball mill. In this paper, a vibration monitoring-based method is proposed and tested for estimating the fill level inside a …
SAG/Ball Mill Sizing. Gross Power Draw and Specific Energy Calculator for Semi-Autogenous Grinding (SAG) and Ball Mills. Return to Mill Calculators.
This paper compares the performance of a 25/75 pebble/ball (volume ratio) composite charge to ball-milling, under conditions typical for a ball-mill in SABC circuits, i.e. a large ball top size ...
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 …
The semi-autogenous (SAG) mill grinds materials with steel balls as the grinding media, and is the main grinding equipment in industrial production. Liners are equipped in the internal of the SAG mills, which have the function of protecting the barrel and adjusting the trajectory of the medium.
Once you measure the ball charge and measure the total charges then you need to target an appropriate ball to rock ratio for a chosen mill throughput rate. With high aspect ratio SAG mills total charge to ball charge ratio should be greater than 2 (up to 2.5) for a …
SAG mill optimization to feed ball mill optimized P80. Most SAG mill are not optimized for the combined SAG & Ball mill throughput such as: SAG & Ball mill % ball content SAG …
the fill level ratio, and the steel ball ratio on the SAG mill. Finally, through statistics and analysis of particle information and mill power under different conditions, we analyzed the influence of three parameters on the particle fracture effect in the SAG mill and obtained the best operating parameters of the SAG mill. 2.
1. Introduction. Mill filling has a dominant effect on grinding mill performance (Apelt, Asprey and Thornhill, 2001), and therefore, its accurate measurement is vital for modelling grinding mill performance.Measuring filling is also necessary to estimate the composition of the load for mill modelling: rock and slurry for AG mills; rock, balls and …
A) Total Apparent Volumetric Charge Filling – including balls and excess slurry on top of the ball charge, plus the interstitial voids in between the balls – expressed as a percentage of the net internal mill volume (inside liners). B) Overflow Discharge Mills operating at low ball fillings – slurry may accumulate on top of the ball charge; causing, …
calculating steel ball level in sag mill. Webeffects of end mill length to depth of cut that is if shortening stickout by 1/3 does end mill depth of cut increase by 3x39 or 3x3x327 1/2 HSS end mill 2 stickout max recommended DOC in 1018 Steel x 9 x 27 so if to 3rd power with end mill stickout you can take a DOC if it stuck out that far .
CERAMIC LINED BALL MILL. Ball Mills can be supplied with either ceramic or rubber linings for wet or dry grinding, for continuous or batch type operation, in sizes from 15″ x 21″ to 8′ x 12′. High density ceramic linings of uniform hardness male possible thinner linings and greater and more effective grinding volume.
In large-scale mining, SAG (Semi Autogenous Grinding) mills are widely used. These mills use steel balls that go up to 6.5" in diameter and have a high risk of fracturing the internal linings of the mill. Potential impacts of the steel balls against the mill lining will be generated if the rotational speed of the mill is greater than that ...