Jul 26, 2017 Hard ore Work Index 16 = 100,000/65,000 = 1.54 kwh/t. For the purposes of this example, we will hypothesize that the the crushing index of the hard ore with the increased energy input of 1.54 kw/t reduces the ball mill feed size to 6,500 micrometers. As a result, the mill output will increase with this reduced size to approximately 77,000 tons
Get PriceVery large tonnages can be ground with these ball mills because they are very effective material handling devices. Ball mills are rated by power rather than capacity. Today, the largest ball mill in operation is 8.53 m diameter and 13.41 m long with a corresponding motor power of 22 MW (Toromocho, private communications)
The question how the space between steel ball and ore/rock particle is filled in the mill depends on the size distribution of the feed material and steel ball .For the optimal performance a factor of 10 - 25 times the size of ore can be used to establish the size distribution of the steel ball
Aug 02, 2013 Based on his work, this formula can be derived for ball diameter sizing and selection: Dm = 6 (log dk) * d^0.5 where D m = the diameter of the single-sized balls in mm.d = the diameter of the largest chunks of ore in the mill feed in mm
Generally, filling the mill by balls must not exceed 30–35% of its volume. Productivity of ball mills depends on drum diameter and the relation of drum diameter and length. Optimum ratio between length L and diameter D, L: D is, usually, accepted in the range 1.56–1.64
Investigations were carried out in a laboratory ball mill having the size of DxL = 160x200 mm with a ribbed inside surface of the drum. The mill ball loading was 40% by volume, the rotation rate was equal to 85% of the critical speed. Balls were made from steel: S4146, extra high quality, having hardness 62
Oct 12, 2016 The size of the balls used for grinding depends on the size of the material entering the mill; they should be just large enough to break the biggest lump of ore likely to be encountered. Balls of 5-in. diameter are the largest in common use, but they are only suitable for coarse feeds of 1-in. size or over
MillStar’s Segregated Ore Feed Controller is designed to: • Prevent mill . overloads. • Adjust the coarse and fine feeder ratios to make optimum use of the ore supply and limit the need to grind the mill out. • Interact with operators’ rating of the coarseness of each feeder to determine the size distribution of feed material
Aug 21, 2021 The correct ratio of ball size to ore size is often determined by trial and error, primary grinding usually requiring a grade charge of 10-15 cm diameter balls, while secondary grinding requires 5-2cm. Charge Volume. The charge volume is about 40-50% of the internal volume of mill about 40% of this being void space
Ball Size vs. Grindability. It has been recognized that the grindability of an ore in a ball mill is a function of both feed and mill parameters: Work index, W i; Largest particle size and size distribution; Density of solids and slurry; Mill diameter; Rotational speed; Rowland and Kjos (1980) defined the largest ball size needed based on
Simulation Of Size Reduction In Ball Mills And Dem. Mar 03, 2015 The mill with 30 cm in diameter and 30 cm in length and the test conditions are standardized, with a maximum ball size of 40 mm and an ore top size of 3.35 mm. With less than 300 balls, it poses no challenge in running the simulations, if
Ball Size vs. Grindability. It has been recognized that the grindability of an ore in a ball mill is a function of both feed and mill parameters: Work index, W i; Largest particle size and size distribution; Density of solids and slurry; Mill diameter; Rotational speed; Rowland and Kjos (1980) defined the largest ball size needed based on
maximum ball size in ball mill. Maximum SizeReduction In ABall MillIs Done By FTMLIE .Maximum sizereduction in aball millis done by calculate and selectball mill ball sizefor optimum grinding based on his work this formula can be derived forballdiameter sizing and selection dm log dk d where d m the diameter of the singlesizedballsin mmd the diameter of the largest chunks of ore in themillfeed
The Optimal Ball Diameter In A Mill Strona Gwna. The optimal ball diameter in a mill nedeljko magdalinovic milan trumic maja trumic b max is the maximum ball size fractions of quartz and copper ore as well as the specific mill throughput with the ball charge of various sizes table 1 characteristics of ball charge and sample mass of quartz and copper ore
Coppermolybdenum ore. the figure above is a simplified flow sheet showing the basic steps involved in a copper mill producing the byproduct molybdenum. the crushed copper ore containing, for example, 0.75 cu and 0.015 mo is fed to the grinding circuit where water is added and the ore is ground to the proper size
2.4 Effect of ball size 29 2.4.1 Empirical approaches 29 2.4.2 Probabilistic approaches 33 2.5 Abnormal breakage 36 2.6 Effect of ball mixture 37 2.6.1 Ball size distribution in tumbling mills 37 2.6.2 Milling performance of a ball size distribution 40 2.7 Summary 41 Chapter 3
Ball Mills 【Capacity】 From 0.2-90 T/H 【Advantages】Designed for long service life, minimum maintenance, can grind and homogenize mineral ores down to the nano range, large volume of processing capacity 【Max Feeding size】 25mm 【Discharge size】0.075-0.4mm 【Types】overflow ball mills, grate discharge ball mills 【Service】 24hrs quotation, custom made parts, processing flow
The ball mills are filled with 38 % of their volume with 3-inch wrought steel balls used to further reduce (grind) the ore size. The product of the mill is pumped to the classification process comprised of hydro cyclones, where two products are generated; 1) a fine ore, which is expulsed thorough the top of the cyclone, and
Nov 26, 2019 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
Optimum choice of the make-up ball sizes for maximum. Sep 01, 2013 Fig. 6 shows one set of results, where the circuit capacities are shown in three-ball-size ternary diagrams for various feed sizes with a circulation ratio of 2.5 at a size reduction ratio of 45:1 using a 1 m diameter ball mill
ball mill maximum ball size. Jun 25 2018 Mill effective diameter 223 m 335 is a constant used for dry grinding with steel balls in the mill Actual size of media is taken is lower than the calculated value It is around 80 to 90 mm If you Wants to reduce the maximum ball size thenreduce the feed size by using pregrinding operation
Maximum Ball Mill Gold Ore Input Size In Russia. carbon in pulp - wikipedia. carbon in pulp (cip) is an extraction technique for recovery of gold which has been liberated into a cyanide solution as part of the gold cyanidation process.. introduced in the early 1980s, carbon in pulp is regarded as a simple and cheap process. as such it is used
The ball mill work index laboratory test is conducted by grinding an ore sample prepared to 100% passing 3.36 mm (6 mesh) to product size in the range of 45-150 m (325-100 mesh), thus determining the ball mill work index (Wi B or BWi). The work index calculations across a narrow size range are conducted using the appropriate laboratory work