Abstract

The present invention relates to a system and method for dry recovery of iron oxide fines from compact iron-bearing rocks, comprising primary crushing means (5), secondary crushing means (6) and tertiary crushing means (7, 7') for the preliminary particle size reduction of ore containing iron oxide fines in compact rocks; fine grinding means (9, 10, 21) down to the particle size at which the iron oxide minerals are released, using particle size-reducing cutting means; static air classifying means (11, 12, 13) for intermediate particle size gradations and retention of the fine fraction in baghouse filters (14); and magnetic separation means (15, 16, 17) of high magnetic intensity in each of the particle size ranges graded by the static air classifying means (11, 12, 13).

IPC Classes  ?

• B03C 1/247 - Magnetic separation acting directly on the substance being separated with material carried by oscillating fieldsMagnetic separation acting directly on the substance being separated with material carried by travelling fields, e.g. generated by stationary magnetic coilsEddy-current separators, e.g. sliding ramp with material carried by travelling fields obtained by a rotating magnetic drum
• B03C 1/03 - High gradient magnetic separators with circulating matrix or matrix elements rotating, e.g. of the carousel type
• C22B 61/00 - Obtaining metals not elsewhere provided for in this subclass

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.

IPC Classes  ?

• B03B 7/00 - Combinations of wet processes or apparatus with other processes or apparatus, e.g. for dressing ores or garbage
• B03B 9/00 - General arrangement of separating plant, e.g. flow sheets
• B03C 1/10 - Magnetic separation acting directly on the substance being separated with cylindrical material carriers

Abstract

The present invention discloses a system and a method for dry refining iron oxide ore fines and superfines in dams for waste and low-grade rejected ores, comprising a drier (9) with hot air injection, mechanical stirring means and shafts provided with blades (9.2) for disaggregating and moving the material horizontally and vertically; a number of air classifiers which are operationally connected to the outlet of the drier and classify the fine and super fine iron ore into predetermined granulometric ranges; and magnetic separators (13, 16, 19) with magnetic rollers (32, 42, 47) arranged in cascade and formed by rare earth magnets of low and/or high magnetic intensity, the magnetic rollers being arranged at a defined inclination angle.

IPC Classes  ?

• B03C 1/10 - Magnetic separation acting directly on the substance being separated with cylindrical material carriers
• B03C 1/30 - Combinations with other devices, not otherwise provided for
• B03B 9/00 - General arrangement of separating plant, e.g. flow sheets
• B03C 1/247 - Magnetic separation acting directly on the substance being separated with material carried by oscillating fieldsMagnetic separation acting directly on the substance being separated with material carried by travelling fields, e.g. generated by stationary magnetic coilsEddy-current separators, e.g. sliding ramp with material carried by travelling fields obtained by a rotating magnetic drum
• B03B 7/00 - Combinations of wet processes or apparatus with other processes or apparatus, e.g. for dressing ores or garbage

Abstract

The present invention refers to a system and method for the totally dry treatment of iron-ore wastes from previous mining operations, suitable for both the processing of ore wastes deposited in barrages and wastes stored in piles. The present invention solves the problems of magnetic separation processes that employ the wet and waste- dewatering way, eliminating the risks which throwing solid wastes into retention barrages bring by a system and method wherein the moisture degree of the ore is reduced by means of a mechanical stir dryer (using natural gas to prevent contamination), which is then sorted into various fractions and finally separated magnetically, with the important difference of being an entirely dry process.

IPC Classes  ?

• B03C 1/247 - Magnetic separation acting directly on the substance being separated with material carried by oscillating fieldsMagnetic separation acting directly on the substance being separated with material carried by travelling fields, e.g. generated by stationary magnetic coilsEddy-current separators, e.g. sliding ramp with material carried by travelling fields obtained by a rotating magnetic drum
• B03C 1/10 - Magnetic separation acting directly on the substance being separated with cylindrical material carriers
• B03C 1/30 - Combinations with other devices, not otherwise provided for
• B03B 9/00 - General arrangement of separating plant, e.g. flow sheets