| abstract |
The present invention relates to a system and to a process for dry recovery of iron oxide fines from iron-bearing compacted and semi-compacted rocks, comprising means for primary (5), secondary (6) and tertiary (7, 7') crushing for the purposes of preliminary reduction of the particle size of ores containing the iron oxide fines in compacted and semi-compacted rocks; means (10, 10', 21) for fine grinding of the iron oxide ores produced in the primary (5), secondary (6) and tertiary (7, 7') crushing operations, provided with a dynamic pneumatic grader (3.5, 4.6, 5.4); static pneumatic grader means (11, 12, 13) arranged in series for intermediate particle size cutting and sleeve filters (14) for retention of the fine fraction; and magnetic separation means (15, 16, 17), with magnetic rolls (71, 72, 73) arranged in cascade at a variable tilt angle and formed by magnets of low and/or high magnetic intensity. |