Magnetic-gravity separation technology for Anshan type lean magnetite

Abstract

The invention relates to a magnetic-gravity separation technology for Anshan type lean magnetite, which comprises the following steps: after adoption of a first-stage ball mill for ore grinding, a primary cyclone, a first-stage magnetic separator and a secondary cyclone for classification, settled sand is subjected to first-stage sieve screening, an screened product is fed into a spiral chute, concentrate in the spiral chute is fed into a gravity fine sieve, and a screened product by the gravity fine sieve is qualified concentrate; after overflow of the secondary cyclone and the edge tail of the spiral chute are merged, the concentrate is fed into a second-stage sieve after separation by a first-stage dehydration tank and a second-stage magnetic separator; products on the first-stage sieve, the second-stage sieve and the gravity fine sieve as well as mineral tailings in the spiral chute are merged and fed into a concentration magnetic separator, the mixture is fed into a second-stage ball mill for ore grinding after concentration, then the products return to the first-stage magnetic separator, and after separation by a second-stage dehydration tank and a third-stage magnetic separator, the screened product of the second-stage sieve is merged with the screened product of the gravity fine sieve into the final concentrate. The magnetic-gravity separation technology has the advantages that mineral processing technical indexes for the Anshan type lean magnetite are improved, the mineral processing efficiency is improved, and the production cost is reduced.

Description

technical field [0001] The invention relates to the technical field of ore dressing, in particular to an Anshan-type lean magnetite magnetic-gravity beneficiation process. Background technique [0002] Anshan-type lean magnetite belongs to sedimentary metamorphic deposit, which is a fine-grained disseminated iron ore. The natural type of ore is mainly iron-bearing quartzite, which is composed of quartz (or hornblende) and magnetite (including some false hematite), and its main structure is banded and disseminated. Anshan-type lean magnetite ore belongs to high-silicon, low-sulfur and phosphorus-poor iron ore, with less hematite and limonite content, and some ores have relatively high iron silicate and iron carbonate content, and its embedded particle size is fine and uneven. At present, according to the properties of Anshan-type lean magnetite ore, most ore concentrators generally adopt the stage grinding-single magnetic separation-fine screen regrinding process to complete...

AI Technical Summary

Problems solved by technology

At present, according to the properties of Anshan-type lean magnetite ore, most ore concentrators generally adopt the stage grinding-single magnetic separation-fine screen regrinding process to complete the ore separation, and most of the ore concentrators have achieved relatively good beneficiation. However, the process is not perfect, and there are still many defects and deficiencies: First, although the process has carried out tailings on the primary grinding and grading products through magnetic separation equipment, reducing the amount of secondary grinding and grading, the magnetic separation equipment The sorted coarse concentrate contains some magnetite with relatively coarse particle size (0.1mm-0.076mm particle size) that has been completely dissociated from the monomer and then enters the secondary grinding, which not only wastes the grinding cost in vain, but also causes Useful minerals are over-grinded, causing metal loss; second, most of the process requires three-stage grinding operations, and the grinding cost is relatively high; third, the fine screen regrinding cycle of this process is not easy to control

Although this process adds a gravity separation device-spiral chute, which can change the particle size composition of the final concentrate, it has obvious shortcomings in the separation of Anshan-style lean magnetite: first, a spiral classifier is used for primary classification, and the classification efficiency is low. The particle size of the product is relatively coarse, which is not conducive to improving the process index in the next step; the second is to directly feed the primary grading overflow into the spiral chute after coarse and fine grading, and the particle size entering the spiral chute is coarse and has a large amount of ore. The fine screen and the secondary grinding pressure are high, and the index is prone to fluctuations; the third is that the fine screw tail of the spiral chute and the product on the fine screen enter the secondary grinding machine without concentration, resulting in low grinding concentration and poor grinding effect; Fourth, the number of sections of the spiral chute in this process is large, the mill occupies a large area, and the operation and adjustment are difficult

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