Method for recycling tailings of magnetic separation by adopting preselection-calcination-magnetic levitation processes

Abstract

The invention relates to a method for recycling magnetic tailings by adopting preselection-calcination-magnetic levitation processes. The method comprises the following steps of supplying a first period of weak magnetism to the magnetic tailings of which the iron grade is 9 to 13% and the content of iron carbonate is more than 3%, supplying a first period of strong magnetism to the magnetic tail,performing spiral chute reselecting operation of one coarseness and one fineness on one strong concentrate, merging fine spiral tailings and coarse spiral tailings and one strong tailing into primarytailings, and merging fine spiral concentrate and first magnetic concentrate into primary concentrate; condensing, filtering and roasting the primary concentrate so as to obtain roasted ore; performing closed circuit grinding on the roasted ore, supplying a second period of weak magnetism to overflow products of which the -0.046mm content is 83% to 90%, performing reverse flotation of one coarseness and one fineness and three sweep on second magnetic concentrate, wherein the reverse flotation concentrate is final concentrate of which the grade is more than 65%, and merging the tailings of a centrifugal machine and second magnetic tailings and the primary tailings into final tailings of which the grade is 7% to 10%. The method has the advantages that (1) preselection is performed without grinding; (2) magnetic separation is combined with reverse flotation, the regrinding particle size is coarse, and the yield is increased.

Description

technical field [0001] The invention belongs to the technical field of mineral processing, and in particular relates to a method for separating magnetic separation tailings with an iron carbonate content of more than 3% and recovering magnetic separation tailings through a preselection-roasting-magnetic gravity process. Background technique [0002] At present, the method of recovering magnetic separation tailings whose useful minerals are mainly magnetic iron minerals is generally to use magnetic separation-fine sieve-magnetic separation process or single magnetic separation process to separate the magnetic separation tailings. The purpose of recycling magnetic iron minerals is to obtain qualified iron concentrates. The selection of a single magnetic separation process or magnetic separation-fine screening-magnetic separation process is determined according to the particle size of the magnetic iron minerals embedded in the magnetic separation tailings. The details are as fo...

AI Technical Summary

Problems solved by technology

[0012] Adopting the above-mentioned recovery process of the magnetic tailings of magnetic iron minerals as the main useful minerals, not only the recovery rate of magnetic iron is relatively low, but also the iron carbonate lost in the tailings cannot be recovered at all;

[0013] Using the existing recovery process for the comprehensive tailings of hematite whose useful minerals are mainly weak magnetic iron minerals, the pre-selection process is magnetic separation-regrinding-magnetic separation, and the magnetic separation tailings are recovered by strong magnetic Compared with the feed ore, the grades of the two high-strength magnetic concentrates before and after regrinding are below 15% and below 21% for the second-strength high-quality concentrate. The process is reasonable, and iron carbonate can be converted into magnetic iron, but the follow-up weak magnetic separation operation needs to obtain iron concentrate with a grade of 65%, and the regrinding particle size must reach more than 97% of -500 mesh. The regrinding particle size is too fine, and the cost is extremely high , and it is difficult to realize industrial application

Images