#### Kinetic grinding test approach to estimate the ball mill work index

The mill is scaled down with a coefficient of twothirds from the standard Bond ball mill. Therefore, it requires smaller amounts of sample and the test is done faster. View.

The mill is scaled down with a coefficient of twothirds from the standard Bond ball mill. Therefore, it requires smaller amounts of sample and the test is done faster. View.

The ball mill work index is shown below. BM Wi (kWhr/st) = BM Wi (kWhr/mt) = Bond Ball Mill

In the paper proposed by García et al. [5], a deep study on the Bond ballmill and Bond rodmill standard tests is shown with different ores. The most impacting result of this work is the ...

The standard Bond ball mill test requires a material of appropriate granulometric composition, 100% − mm created by a stagecrushing process, which is ground in a ball mill. A small number of very brittle ores can naturally generate very fine sizes, in spite of being correctly prepared. Levin (1989) proposed a method for determining the ...

The Bond ball mill grindability test is one of the most common metrics used in the mining industry for ore hardness measurements. The test is an important part of the Bond work index methodology ...

The basic parameters used in ball mill design (power calculations), rod mill or any tumbling mill sizing are; material to be ground, characteristics, Bond Work Index, bulk density, specific density, desired mill tonnage capacity DTPH, operating % solids or pulp density, feed size as F80 and maximum 'chunk size', product size as P80 and maximum a...

The 16 tests are made up of combinations of four different feed sizes and four different ball size distributions as detailed in Table 2. The ball charge in each test maintained the Bond ball charge mass of 20 and discussion. The Bond Ball Mill Work Index (W i) was measured as 24 kW h/t at a test screen size of 106 μm.

Based on his work, this formula can be derived for ball diameter sizing and selection: Dm <= 6 (log dk) * d^ where D m = the diameter of the singlesized balls in = the diameter of the largest chunks of ore in the mill feed in mm. dk = the P90 or fineness of the finished product in microns (um)with this the finished product is ...

Average grinding work index (Wi) by type of mate rial, according to Bond (see table ): The work index (Wi) expresses the kWh required to reduce a short ton of material from theoretically infinite feed size to 80 % passing a square screen opening of 100 microns. The work index values apply to ball mills grinding wet in closed circuit.

Bond presents use of his breakthrough formula relating comminution circuit feed size (F80), circuit product size (P80) and the ore Work Index to industrial equipment energy usage. It covers crushing, rod and ball milling. The Bond Ball Mill Work Index remains today as the only tool used for ball mill scaleup design.

Ball Mills or Rod Mills in a complete range of sizes up to 10′ diameter x 20′ long, offer features of operation and convertibility to meet your exact needs. They may be used for pulverizing and either wet or dry grinding systems. ... (Bond, 1961; Rowland and Kjos, 1978), relates to: 1) Rod milling a rod mill with a diameter of ...

Berry and Bruce (1966) and Horst and Bassarear (1977) devised an approximate procedure comparing the grindability data of an unknown ore with a reference ore whose grindability data are known and determined in a Bond ball mill. The test is performed on samples of size − mm in any laboratory mill with balls.

The Ball mill work index is the final Bond work index, applicable to the size range of ball milling (very roughly: from mm to about 75 µm; yes, it overlaps the Rod Mill Wi range). More on ...

The Bond ball mill grindability test is one of the most common metrics used in the mining industry for ore hardness measurements. The test is an important part of the Bond work index methodology ...

The Bond Work Index (Wi) is a common technique for the estimation of hardness and energy requirement for comminution using ball mills. However, this technique is timeconsuming (close to 5 hours ...

These experiments were run based the Bond Ball Mill Grindability Test. The main difference that was being investigated was the impact of using a testing mill with a 4inchX8inch hand hole door in ...

Bond Ball Mill Standard Test The procedure to carry out the Bond grindability test [1,18] is described below. The test is performed in the socalled Bond's standard ball mill, a laboratory mill 1200 1200, running at 70 rpm (BICO, San Francisco, CA, USA) with rounded inner edges and without lifters.

Bond Ball Mill Grindability Test. The test determines the Bond Ball Mill Work Index which is used with Bond's Third Theory of Comminution to calculate net power requirements*. Various correction factors may have to be applied. W = Wi (10/√P 10/√F) Where W = Net power consumption in kWh/t Wi = Bond work index (either Imperial or Metric ...

The work index equation for a ball mill test was generated by Fred Bond to empirically predict the operating work index of an industrial ball mill (8 ft dia by 8 ft effective grinding length ...

In particular, the Bond work index (wi) is considered a critical parameter at an industrial scale, provided that power consumption in comminution operations accounts for up to 40% of operational costs. Despite this, the variability of wi when performing the ball mill Bond's standard test is not always understood enough.