The pilot circuit specific energy consumption was 3.3 kWh/t, versus the plant ball mill circuit value of 10.2 kWh/t. Fig. 5. The PGM pilot plant at Corem steady-state conditions. Full size image.Web

Objectives. At the end of this lesson students should be able to: Explain the grinding process. Distinguish between crushing and grinding. Compare and contrast different type of equipment and their components used for grinding. Identify key variables for process control. Design features of grinding equipment (SAG, BALL and ROD MILLS)Web

The second challenge after getting the correct kWh/t for the SAG and ball mill on a suite of variable hardness samples is to decide whether the design will be for fixed tonnage or variable tonnage. The effect of variable tonnage on recovery must be unknown because no one seems to be interested in this effect even in copper flotation plants ...Web

Specific energy consumption (kWh/t) HPGR-ball mill: 14.7: 20.0: VRM: 19.6: 27.5: Horomill: 14.4: 17.5: Ball mill: 14.4: 32.5: The results show that high compression grinding mill circuits are more energy efficient than conventional single stage multi-chamber ball mill circuits. The circulating load ratio around the circuit is much higher ...Web

An alternative mill ball charge is proposed that closely approximates Bond's original total ball mass, number of balls and ball surface area. Results of 30 Bond Work index tests of six pure materials (calcite, magnesite, labradorite (feldspar), quartz, andalusite and glass) using closing screen apertures (P 1 ) values of 500, 250, 125, 90 and ...Web

Ball mill specific energy kWh/t 20.9 14.8 Pebble crusher specific energy kWh/t 0.10 0.23 Auxiliary specific energy kWh/t 2.50 2.00 1.50 Total Specific Energy kWh/t 25.3 27.5 28.0 The operating cost is based on consumables and the general maintenance cost factored from the predicted capital and does not include labour. ...Web

The crushing-ball milling circuit specific energy was estimated on the basis of the Bond equation and the relevant Bond work indices (Table 4), with the crushing energy given from the SAG/AG F80 to a nominal product with P80 of 8.0 mm being added to the ball mill energy from F80 of 8.0 mm to the actual P80 of the pilot test, given either by the ...Web

It was found that the ball mill consumed 54.67 kWh/t energy to reduce the F 80 feed size of 722.2 µm to P 80 product size of 275.4 µm while stirred mill consumed …Web

Circuit Bond work index (kWh/t) Specific energy consumption (kWh/t) HPGR-ball mill 14.7 20.0 VRM 19.6 27.5 Horomill 14.4 17.5 Ball mill 14.4 32.5 The results show that high compression grinding mill circuits are more energy efficient than conven- tional single stage multi-chamber ball mill circuits.Web

= 1.12 kWh/t when expressed in terms of the crusher feed rate ... Ball mills in HPGR-Ball mill circuits tend to have more installed capacity than their counterparts in AG/SAG-Ball mill circuits.Web

The mill was expected to produce a product of 80% passing 150 mm. The feed rate to the mill was 300 t/h. The ball mill grindability test at 65 mesh showed 12 kWh/t. The internal diameter of the ball mill was 5.03 m and the length-to-diameter ratio was 0.77. The steel balls occupied 18% of the mill. The total load occupied 45% of the mill volume.Web

As shown in this figure, the rotational speed of the mill has a major influence, with nearly 40% of energy saving when this operating condition is varied, from 13.3 kWh/t to 8 kWh/t, while the rotational speed is reduced from 80% to 50% of the Vc . The same pattern is observed when the media charge is varied, from 10.6 kWh/t to 7.8 kWh/t, …Web

With the models proposed for α, β, and γ, the Bond Work Index (kWh/t) can be rapidly estimated (less than 2 hours) and show a high accuracy for mills of non-standard dimensions (R2