Magnetic separation method of pyrite roasting slag

Abstract

The invention discloses a magnetic separation method of pyrite roasting slag, which comprises following steps: feeding the roasting slag into a ball mill and adding water to grind into ore pulp, wherein first grade magnetic separating adopts a high intensity magnetic separator with a magnetic field intensity of 2600Gs, the ore pulp is conveyed into the first grade magnetic separator by using a slurry pump for primary separating, residue after magnetic separating is conveyed into a tailings pond for settling, and a magnetically separated material flows to the second grade magnetic separating, second grade magnetic separating adopts a medium intensity magnetic separator with a magnetic field intensity of 1200-1400Gs, first fine selecting is performed, a magnetically separated material flows to a third grade magnetic separating and the residue after magnetic separating returns back to a pulp pool, third grade magnetic separating adopts a low intensity magnetic separator with a magnetic field intensity of 800-1200Gs, second fine selecting is performed, the magnetically separated material flows to a concentrate pool and is settled as iron concentrate, and the residue after magnetic separating returns back to the pulp pool. A total recycle rate of iron element of the method is high and a concentrate grade is high.

Description

technical field [0001] The invention relates to the technical field of chemical industry, in particular to a magnetic separation method for pyrite roasting slag. Background technique [0002] The main component of pyrite is FeS 2 , commonly known as pyrite, after being washed and enriched by the concentrator, the sulfur content reaches about 35%, the iron content is about 30%, and other minerals include CaCO 3 、AL 2 o 3 and trace elements such as As, Pb, Zn, P, Cu, etc., SiO in pyrite components 2 and AL 2 o 3 It does not participate in the reaction of sulfur and iron in roasting acid production, and other As, Pb, Zn and other contents are very small, which will remain in the slag, which meets the quality requirements of iron fine powder. [0003] Factors such as the magnetic susceptibility and fineness of slag, the magnetic field strength of the magnetic separator will affect the concentrate yield and concentrate grade. The magnetic susceptibility of slag, that i...

AI Technical Summary

Problems solved by technology

The stronger the magnetic field of the magnetic separator is, the more favorable the magnetic separation is, but the increase of the magnetic field strength will cause some weakly magnetic minerals to be adsorbed into the concentrate. Although the yield will increase, the grade of the concentrate will decrease accordingly.

[0004] The fineness of slag is also a key factor affecting the yield and grade of concentrate. Theoretically, the higher the fineness, the better the separation of iron mineral monomers in slag, and the better the yield and grade of concentrate. However, if the slag is too fine, it will cause magnetic separation and Severe tailing when the concentrate settles, which affects the concentrate yield