Narrow-fraction beneficiation method for magnetite

Abstract

The invention discloses a narrow-fraction beneficiation method for magnetite, and belongs to the technical field of beneficiation. The method comprises the following steps: 1, carrying out wet screening on coarse-grain magnetic separation concentrate; 2, products with the size of + 0.5 mm on the wet-type screen enter a first-stage ball mill for ore grinding; 3, the ore discharging product of the ball mill and the minus 0.5 mm undersize product of the wet screening are subjected to cyclone classification, and settled sand and overflow are obtained; 4, hydrocyclone overflow is subjected to first-stage magnetic separation, and concentrate and tailings are obtained; 5, first-stage magnetic separation concentrate is subjected to pre-classification through a cyclone, and settled sand and overflow are obtained; 6, sand settled in the cyclone is subjected to ore grinding through a second-stage tower mill, overflow in the cyclone is subjected to secondary magnetic separation, and concentrate and tailings are obtained; 7, secondary magnetic concentrate enters a cyclone to be subjected to deenrichment, and settled sand and overflow are obtained; and 8, taking the settled sand as final total concentrate if the grade of the settled sand meets the requirement. The ore grade is greatly improved through the cyclone deenrichment technology; meanwhile, a high-frequency fine screen is omitted, the fine selection technological process is simplified, the number of started equipment is reduced, and energy conservation and consumption reduction are effectively achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of ore dressing, more particularly to a narrow size fraction ore dressing method for magnetite. BACKGROUND

[0002] In the traditional magnetite ore dressing process, the industry generally adopts a combined process of multi-stage grinding, multi-stage magnetic separation combined with high-frequency fine screening classification to realize the improvement of concentrate grade. However, the traditional process has many outstanding problems in practical application: first, the high-frequency fine screening classification equipment is prone to blockage, not only the maintenance cost is high, but also the screening efficiency is easily affected by the fluctuation of ore properties, and the stability is poor; second, the multi-stage magnetic separation process is complicated, and a large number of equipment need to be started, resulting in high energy consumption; third, the improvement space of concentrate grade is limited, which is difficult to meet the strict demand of the current market for high-quality iron concentrate; fourth, the particle size control precision is insufficient, and part of the qualified particle size ore is forced to participate in repeated grinding, which not only wastes resources, but also further increases the energy consumption of the grinding link. Therefore, it is an urgent need for the industry to develop a narrow size fraction ore dressing method with simplified process, reduced energy consumption and effectively improved concentrate grade. SUMMARY

[0003] 1. Technical problems to be solved by the present application

[0004] In view of the defects and deficiencies of the prior art, the present application provides a narrow size fraction ore dressing method for magnetite. Compared with the traditional ore dressing process, the present application greatly improves the ore grade by cyclone counter enrichment technology, cancels the high-frequency fine screen, simplifies the concentration process, reduces the number of equipment to be started, and effectively realizes energy saving and consumption reduction.

[0005] 2. Technical scheme

[0006] To achieve the above-mentioned purpose, the technical scheme provided by the present application is as follows:

[0007] The narrow size fraction ore dressing method for magnetite provided by the present application has the following steps:

[0008] Step one: wet screening of coarse particle magnetic separation concentrate;

[0009] Step two: the +0.5mm product of wet screening is fed into a first-stage ball mill for grinding;

[0010] Step three: the ball mill discharge product and the -0.5mm product of wet screening are subjected to cyclone classification to obtain sand and overflow;

[0011] Step four: the overflow of the cyclone is subjected to first-stage magnetic separation to obtain concentrate and tailings;

[0012] Step five: the first-stage magnetic separation concentrate is subjected to cyclone pre-classification to obtain sand and overflow;

[0013] Step six: the sand of the cyclone is ground by the second tower mill, and the overflow of the cyclone is subjected to the second magnetic separation to obtain the concentrate and the tailings;

[0014] Step seven: the second magnetic concentrate is subjected to the counter enrichment in the cyclone to obtain the sand and the overflow;

[0015] Step eight: the sand meets the requirements and is used as the final total concentrate, if not, the sand is subjected to the washing machine I selection; the overflow is subjected to the desliming in the washing machine II;

[0016] Step nine: the tailings of the washing machine I and the tailings of the washing machine II are subjected to the thickening magnetic separation, and the thickening magnetic separation concentrate is returned to the second grinding.

[0017] Further, in the step three, the sand obtained after the cyclone classification is returned to the first ball mill for grinding.

[0018] Further, in the step six, the tower mill discharge product is returned to the cyclone in the step five for classification.

[0019] Further, in the step eight, the concentrate of the washing machine I or the cyclone sand meeting the requirements and the concentrate of the washing machine II are combined as the final total concentrate.

[0020] Further, in the step nine, the thickening magnetic separation tailings are combined with the first stage magnetic separation tailings in the step four and the second stage magnetic separation tailings in the step six as the total tailings.

[0021] 3. Beneficial effects

[0022] Compared with the prior art, the technical scheme provided by the present application has the following beneficial effects:

[0023] (1) Simplify the concentration process, cancel the high-frequency fine screen link in the traditional process, reduce the equipment investment and the number of running devices, and reduce the equipment maintenance cost and the production energy consumption;

[0024] (2) Optimize the classification process, realize the efficient classification and grinding of the minerals through the combination of the second tower mill grinding and the multi-stage cyclone classification, and effectively avoid the problems of over-grinding or under-grinding;

[0025] (3) Combine the cyclone counter enrichment technology with the washing machine selection process, significantly improve the concentrate grade, recover the useful minerals lost in the traditional process, and improve the resource recovery rate. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 The flowchart of the present application. DETAILED DESCRIPTION

[0027] The present application will be further described below in combination with the drawings and examples:

[0028] Embodiment 1

[0029] From Figure 1 It can be seen that the magnetite narrow size fraction beneficiation method of the embodiment has the following steps:

[0030] Step one: wet screening of the coarse-grained magnetic concentrate;

[0031] Step two: the +0.5mm product of the wet screening is fed into a first-stage ball mill for grinding;

[0032] Step three: the ball mill discharge product and the -0.5mm product of the wet screening are subjected to cyclone classification to obtain sand and overflow;

[0033] In step three, the sand obtained after the cyclone classification is returned to the first-stage ball mill for grinding;

[0034] Step four: the cyclone overflow is subjected to first-stage magnetic separation to obtain concentrate and tailings;

[0035] Step five: the first-stage magnetic separation concentrate is subjected to cyclone pre-classification to obtain sand and overflow;

[0036] Step six: the cyclone sand is subjected to second-stage tower mill grinding, and the cyclone overflow is subjected to second-stage magnetic separation to obtain concentrate and tailings;

[0037] In step six, the tower mill discharge product is returned to the cyclone in step five for classification;

[0038] Step seven: the second-stage magnetic concentrate is fed into a cyclone for counter enrichment to obtain sand and overflow;

[0039] Step eight: the sand meets the requirements and is used as the final total concentrate, and if it does not meet the requirements, the sand is fed into a washing machine I for separation; the overflow is fed into a washing machine II for desliming;

[0040] In step eight, the concentrate of the washing machine I or the cyclone sand that meets the requirements and the concentrate of the washing machine II are combined as the final total concentrate;

[0041] Step nine: the tailings of the washing machine I and the tailings of the washing machine II are subjected to thickening magnetic separation, and the thickening magnetic separation concentrate is returned to the second-stage grinding.

[0042] The thickening magnetic separation tailings in step nine, the first-stage magnetic separation tailings in step four, and the second-stage magnetic separation tailings in step six are combined as total tailings.

[0043] Compared with the traditional process, the selective beneficiation process has the following significant technical advantages and economic values:

[0044] (1) Simplify the process flow of concentration, cancel the high frequency fine screen link in the traditional process, reduce the equipment investment and the number of running, reduce the equipment maintenance cost and the production energy consumption;

[0045] (2) Optimize the classification process, realize the efficient classification and grinding of the mineral through the combination mode of two-stage tower mill grinding and multi-stage cyclone classification, effectively avoid the problem of over-grinding or under-grinding;

[0046] (3) Combine the cyclone counter enrichment technology with the washing machine separation process, significantly improve the concentrate grade, at the same time, recover the useful minerals lost in the traditional process, and improve the resource recovery rate.

[0047] Compared with the traditional beneficiation process, the ore grade is greatly improved through the cyclone counter enrichment technology; at the same time, the high frequency fine screen is cancelled, the concentration process flow is simplified, the number of equipment opening is reduced, and the energy saving and consumption reduction is effectively realized.

[0048] The above describes the present application and its embodiments in a schematic manner, which is not limited, and the embodiments shown in the drawings are only one of the embodiments of the present application, and the actual structure is not limited thereto. Therefore, if a person skilled in the art is inspired thereby, without departing from the purpose of the present application, similar structural modes and embodiments can be designed without creativity, which shall belong to the protection scope of the present application.

Claims

1. A method for beneficiation of a narrow size fraction of magnetite, characterized by: The steps are: Step one: coarse-grained magnetic separation concentrate is wet screened; Step two: the +0.5 mm product on the wet screen is fed into a first-stage ball mill for grinding; Step three: the ball mill discharge product and the -0.5 mm product under the wet screen are classified by a cyclone to obtain sand and overflow; Step four: the cyclone overflow is subjected to first-stage magnetic separation to obtain concentrate and tailings; Step five: the first-stage magnetic separation concentrate is subjected to cyclone pre-classification to obtain sand and overflow; Step six: the cyclone sand is subjected to second-stage tower mill grinding, and the cyclone overflow is subjected to second-stage magnetic separation to obtain concentrate and tailings; Step seven: the second-stage magnetic separation concentrate is subjected to counter enrichment in a cyclone to obtain sand and overflow; Step eight: the sand grade meets the requirements and is used as the final total concentrate; if the requirements are not met, the sand is fed into a washing machine I for separation; the overflow is fed into a washing machine II for desliming; Step nine: the tailings from the washing machine I and the washing machine II are subjected to thickening magnetic separation, and the thickening magnetic separation concentrate is returned to the second-stage grinding.

2. The method for magnetite narrow fraction concentration according to claim 1, characterized by the fact that: In the step three, the sand obtained after cyclone classification is returned to the first-stage ball mill for grinding.

3. The method for magnetite narrow fraction concentration according to claim 1, characterized by the fact that: In the step six, the tower mill discharge product is returned to the cyclone in step five for classification.

4. The method for processing magnetite of narrow size fraction according to claim 1, characterized in that: In the step eight, the washing machine I concentrate or the cyclone sand with a grade meeting the requirements and the washing machine II concentrate are combined as the final total concentrate.

5. The method for processing magnetite of narrow size fraction according to claim 1, characterized in that: In the step nine, the thickening magnetic separation tailings are combined with the first-stage magnetic separation tailings in step four and the second-stage magnetic separation tailings in step six as the total tailings.

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