Novel three-stage pre-dressing and crushing process for low-grade magnetite

Abstract

The invention belongs to the technical field of ore dressing in metallurgy and mining industry, in particular relates to a three-stage pre-dressing and crushing process for low-grade magnetite. The process comprises the following steps of: feeding magnetite into a coarse crushing machine, transferring the material discharged from the coarse crushing machine to a first-stage dry-type magnetic pulley by using a rubber belt machine, delivering first-stage ore concentrate products to a middle crushing machine by using the rubber belt machine via a middle crushing machine ore bin, delivering middle crushing machine products to a second-stage magnetic pulley by using the rubber belt machine, screening ore concentrate products by a sieving machine to obtain on-sieve products and under-sieve products, crushing the on-sieve products by a fine crushing machine and mixing the crushed on-sieve products with the products crushed by the middle crushing machine, and then transferring the mixedcrushed products to the sieving machine, delivering the under-sieve products to a third-stage dry-type magnetic separation machine by a belt conveyer, wherein ore concentrates discharged from the from the third-stage dry-type magnetic separation machine are taken as the crushed final products, and waste stone from the magnetic separation machine is stored in a waste stone bin. According to the invention, the dry-type magnetic pulley operation is performed after the coarse crushing operation and the dry-type magnetic separation machine operation is performed after the fine crushing operation, the tailing rejection is performed in advance, therefore the milling grade can be improved and the ore grinding load can be reduced, and further, the purposes of reducing the energy consumption and increasing the economic benefits of ore dressing plants can be achieved.

Description

technical field [0001] The invention belongs to the technical field of beneficiation in the metallurgical mining industry, in particular to a new three-stage pre-selection and crushing process for low-grade magnetite. Background technique [0002] In recent years, with the mining of mines to the deep, the mining conditions of the ore body have gradually deteriorated, the rock interlayers have increased, and the ore output grade has declined. Due to the crushing, sorting and tailing of a large number of mixed rocks, the cost of beneficiation increases, and the rocks are easy to muddy during the grinding process, which restricts the improvement of the grade of iron concentrate. If the ore with low grade and large mixed rock is discarded, it will result in low recovery rate, high stripping ratio, high cost, waste of resources, and the ore supply capacity cannot meet the ore volume demand of the concentrator. Therefore, in order to remove waste ore before grinding, improve the ...

AI Technical Summary

Problems solved by technology

This kind of crushing process still cannot meet the grinding and selection grade for magnetic ore with relatively low raw ore grade.

As a result, part of the qualified gangue of the finely broken ore enters the grinding process, which increases the cost of beneficiation

Images