关键词: 镜铁矿, 磁铁矿, 含铁云母, GYX21-1210型高频振动细筛, 摇床重选

Abstract: Main iron minerals of an iron ore from Henan Province in China are specularite and magnetite，and the main gauges are quartz and mica.The dressing plant originally adopted the process of low intensity magnetic separation with stage grinding and stage separation，high gradient high intensity magnetic separation to produce the magnetite concentrate and speculartie concentrate.However，it is hard to realize grinding for the run-of-mine，and weak magnetic coarse iron-bearing mica are usually mixed into speculartie concentrate，resulting in specularite concentrate grade lower than 60%，and even greatly affecting the comprehensive grade of the concentrate.To solve this problem，the plant joints with the Guangzhou Nonferrous Metal Research Institute to carry out the relevant laboratory tests.Based on the laboratory test results，the GYX21-1210 type high-frequency vibrating fine sieve and the ordinary 6-S type fine shaking table are introduced to optimize the original beneficiation process.That is，the high gradient high intensity magnetic concentrate at two-stage are sieved by 0.074 mm fine screen.The under-screen is directly used as the specularite concentrate，and the over-size ores are separated by the table to obtain the remained specularite concentrate and discard a great deal of tailings.The middles from the table are back to the second stage process.After optimization，the specularite concentrate and the integrated iron grade reached 60.30% and 61.83%，improved by 3.55 percentage points and 1.98 percentage points respectively.Meanwhile，their iron recoveries were increased by 7.52 percentage points and 7.51 percentage points separately.

Key words: Specularite, Magnetite, Iron-bearing mica, GYX21-1210 high frequency vibrating fine screen, Gravity by table