A kind of composite iron ore sorting method

Abstract

The invention discloses a complex iron ore sorting method. The complex iron ore sorting method comprises the following steps of grinding ore with particle size being smaller than 12mm in two stages and grading the ore twice to obtain secondarily-graded overflow; separating slag of the secondarily-graded overflow twice; roughly sorting the screened ore pulp after separating the slag by using weak magnetism, finely sorting the screened ore pulp by using weak magnetism, scavenging the screened ore pulp by using weak magnetism twice, and separating slag of tailing ore scavenged secondarily by using the weak magnetism again twice; concentrating the screened ore pulp after separating slag for the fourth time to obtain clear overflow water for recycling, roughly separating concentration underflow with high concentration by using strong magnetism, and scavenging the underflow with high concentration twice by using strong magnetism. By adopting the complex iron ore sorting method, the iron minerals are fully dissociated; the single separation degree reaches over 90%, so that the sorting of the subsequent usable iron minerals can be facilitated; when the ore is sorted by using weak magnetism, high-grade magnetic ore with strong magnetism is firstly sorted, and then hematite and siderite with weak magnetism are sorted by using strong magnetism; the slag is separated for four times so as to remove the impurities, so that the problem of low efficiency of separating the slag for once is thoroughly solved; the pressure of flushing water is reduced; the ore pulp is smoothly divided and introduced into the sorting process; the slag and the impurities are removed; the purpose of efficiently separating the slag from the ore is achieved.

Description

technical field [0001] The invention relates to the technical field of iron ore beneficiation, in particular to a composite iron ore beneficiation method. Background technique [0002] China's iron ore resources generally have the characteristics of poor, fine, and miscellaneous, that is, iron ore with low iron grade, fine embedded particle size, complex occurrence state, and high impurity content, which lead to complex beneficiation process, high cost and high cost of iron ore concentrate production. Ferrous metal recovery is low. A certain iron mine is a large-scale underground mine. The ore is a composite iron ore. The metal minerals include magnetite, hematite, siderite, and pyrite, which are typical refractory iron ores. The beneficiation process is: the mined raw ore is classified into four grades of 50~20mm, 20~2mm, 2~0.5mm, and 0.5~0mm after crushing and washing. mm tailings, 0.5~0mm fine-grained tailings, and pre-selected concentrates are subjected to grinding and...

AI Technical Summary

Problems solved by technology

[0007] There are problems in the existing technology: the φ1420×1500mm cylindrical sieve used in the process has a screen hole size of 2×2mm, and there is only one slag separation, the screening efficiency is low, and there are still fine-grained ores in the separated slag, of which <0.28mm The dry weight of the ore reached 84.8%, and the iron grade was 43.97%. Without the strong magnetic separation in the next process, it was directly discarded as tailings, which reduced the resource recovery rate; The magnetic iron grade in the ore reaches 2%~5%. When the amount of ore feed fluctuates greatly, the magnetic ore cannot be fully selected, which will cause the phenomenon of subsequent high-gradient magnetic separator rod medium blockage; Sweeping, the hematite iron grade in the tailings after one sweeping is 12%, and the dissociated hematite and siderite cannot be fully selected, which is not conducive to improving the metal recovery rate

[0008] If you want to solve these problems in production, it is very difficult to improve. The structure and platform of the plant have been constructed, and slag separation and sweeping are added during production. The space is limited and no more facilities can be added on site.

If it must be increased, another site needs to be selected, which cannot meet the self-flow of ore pulp, and the investment and energy consumption are relatively high.

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