Method for separating bulk mixed iron ore by magnetic and gravity process

Abstract

The invention provides a method for separating bulk mixed iron ore by a magnetic and gravity process. The method includes the following steps: (1) pretreatment of selected ore: specifically, the mixediron ore is crushed, the particle size is required at 20mm to 60mm, and ore washing is performed so that slime adhering to the surface of the ore is separated out to be independently graded and machined; and ore with the particle size being 20 mm or below is subjected to pre-selection by adopting a weak magnetism-strong magnetism method; and (2) ore grading, magnetic separation and gravity separation combined grading is performed on the bulk mixed iron ore with the particle size being 20 mm to 60 mm for pre-selection tailing discarding, and two products of iron concentrate and tailings are obtained. The method has the characteristics of being low in grading production cost and high in iron recycling rate.

Description

Technical field: [0001] The invention relates to a method for separating bulk mixed iron ore by a magnetic gravity process, and belongs to the technical field of mineral processing. Background technique: [0002] my country's iron ore has the characteristics of lean, fine and miscellaneous, especially the lean ore is more prominent. At present, the iron grade of mining is basically below 35%, so the rate of concentrate ore decreases, the rate of tailings increases, the ecological environment is strict, and tailings are stored and disposed of. The problem is becoming more and more prominent. Therefore, it is an important way to reduce the amount of fine tailings by pre-selection of ore before grinding, improving the iron grade of the ore, throwing away the waste rock and reducing the amount of grinding ore. The pre-selection was originally only used for dry weak magnetic pre-selection for bulk magnetite. In recent years, coarse-grained weak magnetic and fine-grained weak magne...

AI Technical Summary

Problems solved by technology

At present, the bulk dry-type weak magnetic pre-selection technology is relatively mature. Generally, pre-selection is carried out after coarse crushing, a few pre-select after medium crushing, and some pre-select after fine crushing. A few concentrators perform pre-selection after coarse crushing and medium crushing. The problem is that when the weather is wet and rainy, and the ore contains a lot of mud, fine-grained iron ore will stick to the gangue, resulting in metal loss. For example, the scrapping rate of a dressing plant is 10%, of which fine-grained iron ore accounts for 5%. cause loss of resources

There is also a dense medium vibrating chute for pre-selection. It is difficult to control the concentration and density of the dense medium suspension, so the index fluctuates greatly, and the metal loss is large. At the same time, the treatment capacity is small, the water consumption is large, and the production cost is high.

For iron ore with weak magnetism, especially large mixed iron ore containing magnetite, hematite, pyrite, siderite, gangue and other minerals, there is no suitable beneficiation equipment for Wubian at present. and efficient beneficiation process for pre-selection