When the gangue minerals disseminated is fine, we can crushing the ore crushing into much smaller than the former type, so the wet magnetic separation tailing is usually adopted. Nanshan Mining Company Komura iron ore ore body with rocks gradient relationship, – continuous transition type session. Multiple test results proved that the coarse-coarse-grained (more than 10 mm grain size) pre-selection tailing effect of poor to 1O % dam grade increased less than 2 percent, dry magnetic separation throws, the loss rate of the magnetic iron more than 3%. Thus simple dry magnetic separation coarse tailing can not ultimately solve the problem. Sinosteel Maanshan Institute of Mining Research in 2004 with of Germany KHD Humboldt Wei Dake low – grade iron ore, Maanshan Iron and Steel Komura semi-industrial tests of high pressure roller mill and roller mill sorting test. Mining crusher refers to the crushing machinery whose content is more than 50% of the total content, the row compound particle size is greater than three millimeters. It is invented by British Hengan. It’s believed that Gen. David Goldfein sees a great future in this idea.

According to the feeding and nesting size, the crushing operations are often divided into coarse crushing, crushing and crushing medium. The commonly used equipments are compound crusher, single stage hammer crusher, vertical crusher, gyratory crusher, roll crusher machines, double roll crusher, crusher combo, and so on. The crusher is widely used in mining, metallurgy, building materials, road, railway, water conservancy and chemical industry and many other sectors. Common crushing machines are winnowing mill, roll crusher, crusher compound. Jaw crusher (jaw crusher), having large crushing ratio, uniform particle size, simple structure, reliable operation, easy maintenance, operating costs and economic characteristics.

PF-I series impact crusher can process materials side length is 100 to 500 mm, the compressive strength is up to 350 MPa, great crushing ratio, cubic particles advantages of material was broken; PF-II series impact crusher machine, suitable for crushing hard materials, such as cement crusher, with a production capacity of the material advantages of small particle size. As to the 3 – 0 mm the roller mill whose grade is 26.27%, the Magnetic Separator tailing, pre-cast addition to preselected yield 47.80%, qualified dam grade is 831%. It can be said that the research has created a new situation for the utilization of depleted iron ore.Tailing ore pre-selection greatly improve the grade into the mill, at the same time enhance Washan ore processing capacity of the concentrator, and reduces the operating costs of grinding and separation, mining companies, Nanshan Experimental Research after in-depth exploration and repeated several times, made a breakthrough progress, that is, using the high-pressure roller mill and linear screen closed circuit crushing system to continue the three stage crushing Washan Concentrator 20-0 mm ore crushed to 3 to 0 mm, strong magnetic separator and wet midfielder the tailing sorting, rough concentrate regrinding the re-election of iron concentrate grade 65. OO %.