Tailing recovery process adopting preconcentration-roasting-regrinding and magnetic separation method

Abstract

The invention relates to a tailing recovery process adopting a preconcentration-roasting-regrinding and magnetic separation method. The tailing recovery process is characterized by comprising the following steps: concentrate extraction and tailing discarding are carried out by virtue of a preconcentration process which sequentially comprises first-section drum magnetic separation, first-section vertical ring magnetic separation, ore grinding, second-section drum magnetic separation and second-section vertical ring magnetic separation, so that a rough concentrate grade is increased, and a subsequent operation treatment amount is reduced; suspension roasting is adopted, so that a rotational-flow suspension state of rough concentrate materials in a suspension magnetization roasting furnace under the conditions of a high temperature of 500 DEG C and a reducing atmosphere can be ensured, and micro-and fine-grained hematite, siderite and limonite in the rough concentrate materials are converted to magnetic iron minerals; and meanwhile, multi-section continuous fine separation is carried out by virtue of a regrinding and fourth-section low-intensity magnetic separation machine, thus the good indexes of a concentrate grade of more than 65% and a metal recovery rate of 48-55% are obtained.

Description

technical field [0001] The invention belongs to the technical field of iron ore beneficiation, in particular to a pre-enrichment-roasting-regrinding magnetic separation tailings recovery process. Background technique [0002] At present, 10% to 15% of the iron ore lost in the comprehensive tailings with a grinding particle size of -0.074mm is 60% to 70% produced by the concentrator using "stage grinding, coarse and fine separation, and heavy-magnetic-flotation combined process" The materials are mainly red limonite and magnetic iron. The current effective process for the recovery of comprehensive tailings is: use two-stage spiral chute for comprehensive tailings, permanent magnet sweeping, and mix spiral concentrate and permanent magnet concentrate to form coarse concentrate. , Coarse concentrate is ground and then selected by weak magnetic, strong magnetic, reverse flotation or centrifuge process. Using the process of "spiral chute, permanent magnet-grinding-strong magneti...

AI Technical Summary

Problems solved by technology

Therefore, the problem of high grade tailings cannot be solved after the comprehensive tailings are sorted by "spiral chute, permanent magnet-grinding-strong magnetism, centrifuge process", which makes it difficult to further improve the recovery rate

"Magnetic separation-roasting-magnetic separation process" uses strong magnetic to separate the tailings, and then roasts all the obtained strong magnetic concentrates, and then uses weak magnetic to separate the roasted ore. Although this process improves the recovery rate, However, since the distribution rate of magnetic iron in the tailings is 15% to 40%, this part of the product should not be processed in a roasting process with complicated processes (concentration, filtration, drying, etc. before roasting), high energy consumption and high cost.

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