Pre-selection-fluidized roasting-ore grinding magnetic separation process for treating iron tailings

The invention relates to a pre-selection-fluidized roasting-ore grinding magnetic separation process for treating iron tailings. The process is characterized by comprising the following specific steps of: 1) performing weak-strong magnetic pre-selection, tailings discarding and quality improving on on iron tailings; 2) carrying out fluidized roasting on mixed magnetic concentrate; 3) carrying out second-stage weak magnetic pre-selection, tailings discarding and quality improving on the roasted product; 4) finely grinding the second-stage weak magnetic concentrate by using a stirring mill; and 5) performing two-stage continuous weak magnetic concentration on the product of the stirring mill. According to the process, the final concentrate with the iron grade of 62% or above and the iron recovery rate of 65% or above is obtained. Compared with the prior art, the method has the advantages that 1) by using fluidized roasting, weak magnetic iron minerals are converted into strong magnetic magnetite, so that the ef