Some of the dressing plants will send the fine ground ore powder directly into a magnetic separator for magnetic separation. The mineral powders that come from the Ball Mill are not graded and come through the magnetic separation directly, so that the particle sizes of ore powders are uneven.
The coarse grains has lower ore grade. Super fine grains has high ore grade, but the magnetic field strength is low and adsorption ability is poor. With the current coming into tailings, the grade of ore iron concentrate will be lower and tail-running phenomenon is serious. Reminding to the customers that choose this mineral processing technology, the ground materials must come through screening classification and then come to magnetic separation. The reason is that the different ores has different monomer disintegrate particle size in its highest grade. If the grain size is too thick, the impurity in the minerals can not be separated out and the ore grade is too low. If the grain size is too fine, mill grinding ability and grinding time will be waste. For the ore sizes that is less than 10 μ m, if the grains increases 1% in ore powders, the grinding time will increase 2%, power consumption and wear of steel ball lining board will also increase 2%.
Therefore, reducing the content of over-grinding minerals is the most effective method to improve mill production, reduce power consumption and improve iron concentrates powder recovery rate. By using the group screening measures, the ores whose particle size can not meet the requirements come back to mill for another grinding. The ores whose particle size meet requirements are sent to graduation in time so that the concentrate grade is improved and the Grinding Machine efficiency is also improved.
There are many mineral grading methods and spiral classifier is the most primitive grading equipment. Group technology is simple and grading accuracy is slightly less so the spiral classifier is generally applied for grading the discharged ores in a period of grinding. When the iron concentrate of final product whose sizes are not more than 80 μ m should be 100% among the products, the first paragraph gradation can use spiral classifier; the secondary gradation can adopt high-frequency fine screen. When the iron concentrate of final product whose sizes are not more than 80 μ m can be lower than 100% among the products and the large particles proportion of ores is less, the high frequency vibration screen can be used for gradation and the medium ores can come through the magnetic separation but the premise is that the worn of the high frequency separation is not so serious. The coarse ores come back to grinding mill again.
There still has a kind of gradation equipment. that is hydrocyclone. Now there are many large concentrators take out the first stage and second stagespiral classifier and use the hydrocyclone. This method can do the ore powder size gradation and also can improve the pulp density before the magnetic separation and reduce dewatering equipment. This equipment is also used in dryer grading enrichment of the ore pulp before ore powder re-selection without dryer grading enrichment, which has a good effect.
From the above, SBM Machinery used process improvement to make the grade of products increased more than 66.5% and make the products get a good price. Then through equipment technical renovation, the production power consumption of mining machinery is decreased by more than 25% and the yield is increased by 30% or so. Steel consumption of lining board and hammer and steel ball is reduced by 15% or more.
The comprehensive economic indexes reach the international advanced level, and the enterprise economic benefit is improved, and the competitive power of enterprises is also improved. These will create good conditions for the future development of the enterprise. SBM Machinery professional ore dressing team will fully consider all sorts of factors and provide energy-saving and high efficiency production line for you so that our customers can achieve maximum economic benefit.
