Practical application method for flotation and purification of high-silicon and high-calcium magnesite

Abstract

The invention belongs to the technical field of magnesite beneficiation, and provides a high-silicon and high-calcium magnesite flotation purification practical application method which comprises the following steps: carrying out crushing screening and ore grinding grading treatment on raw magnesite; the method comprises the following steps: fully mixing magnesite raw ore with qualified size fraction with an agent, and automatically flowing to a flotation unit through a pipeline to carry out reverse flotation rough washing operation; reverse flotation fine selection operation is carried out through three flotation units; filtering, dewatering and blending the qualified positive-selection concentrate into a solution, and carrying out positive-selection roughing operation; the concentrate obtained after positive selection and roughing enters a fine selection process section, and low-silicon low-calcium first-grade concentrate powder is obtained; carrying out dehydration treatment, and supplying dehydrated concentrate powder as a raw material to a downstream workshop; according to the method, through the direct and reverse flotation and reagent processes, the content of silicon and calcium in the magnesite is effectively reduced, the content of MgO in the magnesite is increased, and resource utilization in the field of the magnesite is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of magnesite beneficiation, and specifically is a practical application method for flotation purification of high-silicon and high-calcium magnesite. Background Art

[0002] With the development of economy, the requirements and quality of steel are getting higher and higher, which also puts forward higher requirements for metallurgical industry. Heat-resistant refractory materials are important auxiliary materials for steel smelting, and magnesite is the main raw material for producing refractory materials. As an important non-metallic mineral resource, magnesite is widely used in refractory materials, building materials, chemical industry and other fields. However, with the continuous mining of mineral resources, high-grade magnesite resources are becoming increasingly exhausted, and low-grade, high-silicon and high-calcium magnesite has gradually become the main mining object. This type of ore has a low direct utilization value due to the high content of silicon and calcium impurities, and needs to be purified to improve its quality.

[0003] However, the purification methods for high-silicon and high-calcium magnesite mainly include physical beneficiation and chemical beneficiation. Although physical beneficiation methods such as gravity separation and magnetic separation are easy to operate, the purification effect is limited and it is difficult to meet the demand for high-purity magnesite products. Chemical beneficiation methods such as acid leaching and alkali fusion have good purification effects, but they have high energy consumption, high cost, and great environmental pollution, and are easy to damage the structure of magnesite, affecting its application performance.

[0004] As an efficient mineral separation technology, flotation is widely used in the purification of various ores. However, when dealing with high-silicon and high-calcium magnesite, traditional flotation methods have problems such as large reagent consumption, low flotation efficiency, and difficulty in improving the concentrate grade. Specifically, since the silicon and calcium impurities in high-silicon and high-calcium magnesite have similar floatability to the magnesite itself, it is difficult to effectively separate them during the flotation process. In addition, traditional flotation reagents are often not very selective for ores, which can easily lead to excessive reagent consumption and environmental pollution.

[0005] To this end, technicians in this field have proposed a practical application method for flotation purification of high-silicon and high-calcium magnesite, aiming to achieve efficient purification of high-silicon and high-calcium magnesite, reduce the impurity content, optimize the slurry processing process, and increase resource utilization in the magnesite field. Summary of the invention

[0006] In order to solve the above technical problems, the present invention provides a practical application method for flotation purification of high-silicon and high-calcium magnesite to solve the problems raised in the background technology.

[0007] A practical application method for flotation purification of high-silicon and high-calcium magnesite, comprising the following steps:

[0008] S1, crushing, screening, grinding and grading the raw magnesite;

[0009] S2. The magnesite ore of qualified particle size is fully mixed with the reagent and flows through the pipeline to the flotation unit for reverse flotation and rough washing;

[0010] S3, reverse flotation and selection are carried out through three groups of flotation units, and the reagents are fully reacted before each selection;

[0011] S4, filtering and dehydrating the qualified positive concentrate obtained by reverse flotation to prepare a solution, adding a regulator and a dispersant, and performing positive roughing operation;

[0012] S5. The concentrate after roughing is sent to the concentration process section, where a collector is added and the air volume is controlled to obtain a low-silicon and low-calcium primary concentrate powder;

[0013] S6. Dehydrate the concentrate powder obtained from the positive selection, and send the dehydrated concentrate powder to the warehouse to supply it to the downstream workshop as raw material.

[0014] Preferably, in step S1, the ore is classified after grinding to obtain a selected particle size of -200 mesh accounting for 75%.

[0015] Preferably, the underflow of the flotation unit in step S2 is a roughing concentrate, which flows to the intermediate box by gravity, and the reagent is a fatty acid collector or an amine collector.

[0016] Preferably, the reverse flotation operations in step S3 are respectively concentrating I, concentrating II and concentrating III, and the bottom flow of the flotation unit is the concentrate of each concentrating;

[0017] The reverse flotation selection I is to make the roughing concentrate flow to the first group of flotation units after the roughing concentrate fully reacts with the reagent in the intermediate box, and fully contact with the low-pressure air. The bottom flow of the flotation unit is the selection I concentrate, which flows to the intermediate box by gravity.

[0018] The reverse flotation selection II is to react the selected I concentrate with the reagent, and then flow to the second group of flotation units, fully contact with low-pressure air, and the bottom flow of the flotation unit is the selected II concentrate, which flows to the middle box by gravity;

[0019] The reverse flotation selection III is to react the selected II concentrate with reagents, and then flow to the third group of flotation units to fully contact with low-pressure air. The bottom flow of the flotation unit is a qualified positive selection concentrate.

[0020] Preferably, in the reverse flotation selection operation, the reagents used for the third selection are fatty acid collectors and sodium sulfate inhibitors; the low-pressure air pressure is between 0.03-0.1MPa, and a Roots blower is used for air supply, and the bubble diameter of the low-pressure air is between 1-2mm.

[0021] Preferably, the adjusting agent added in step S4 is sodium sulfate, and the dispersing agent is polyacrylamide;

[0022] The collector in step S5 is a fatty acid collector, and the air volume is controlled between 0.2-0.5 cubic meters of air / cubic meters of slurry.

[0023] Preferably, in the step S6, the foam generated by the flotation unit during the positive selection operation is scraped out by double-sided scrapers to the foam tank, combined into the middlings, and flows through the pipeline to the dehydration operation for treatment.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1. The present invention effectively reduces the silicon-calcium content in magnesite and increases the MgO content in magnesite through forward and reverse flotation and reagent processes, thereby increasing resource utilization in the magnesite field and avoiding waste of magnesite resources.

[0026] 2. The present invention greatly reduces silicon and calcium impurities in the concentrate and improves the grade and product quality of magnesium ore through the effective combination of reverse flotation and concentration processes; the reagents, air pressure and air volume used not only improve the efficiency of the flotation process, but also reduce energy consumption; and the implementation of this method promotes the effective utilization of high-silicon and high-calcium magnesite resources, gives full play to the potential value of the ore, and promotes the sustainable development of mineral resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The present invention is a flow chart of the practical application method of flotation purification of high-silicon and high-calcium magnesite. DETAILED DESCRIPTION

[0028] The following embodiments of the present invention are described in further detail in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0029] As attached Figure 1 As shown:

[0030] Embodiment 1: The present invention provides a practical application method for flotation purification of high-silicon and high-calcium magnesite, comprising the following steps:

[0031] S1. The magnesite ore is crushed, screened, ground and classified; after grinding, the ore is classified to obtain a selected particle size of -200 mesh accounting for 75%.

[0032] By crushing and grinding, the particle size of magnesite particles is reduced to meet the particle size range required for flotation, thereby enhancing the reaction rate and efficiency of the subsequent flotation process.

[0033] S2. The magnesite ore of qualified particle size is fully mixed with the reagent and flows through the pipeline to the flotation unit for reverse flotation and rough washing operation; the bottom flow of the flotation unit is the roughing concentrate, which flows to the intermediate box by gravity. The reagent is a fatty acid collector or an amine collector.

[0034] The qualified granular minerals are fully mixed with reagents for roughing to remove high silicon and high calcium impurity minerals. The collectors (fatty acids or amines) used promote the flotation of qualified magnesium minerals, which float up to the concentrate, while the impurities remain in the bottom flow, improving the quality foundation of subsequent selection.

[0035] S3, reverse flotation and selection are carried out through three groups of flotation units, and the reagents are fully reacted before each selection; the reverse flotation and selection operations are respectively selection I, selection II and selection III, and the bottom flow of the flotation unit is the concentrate of each selection;

[0036] Reverse flotation concentration I is to make the rougher concentrate flow to the first group of flotation units after the rougher concentrate fully reacts with the reagent in the intermediate box, and fully contact with the low-pressure air. The bottom flow of the flotation unit is the concentration I concentrate, which flows to the intermediate box by gravity;

[0037] Reverse flotation selection II is to react the selected I concentrate with reagents, and then flow to the second group of flotation units to fully contact with low-pressure air. The bottom flow of the flotation unit is the selected II concentrate, which flows to the middle box by gravity.

[0038] Reverse flotation selection III is to react the selected II concentrate with reagents, and then flow to the third group of flotation units to fully contact with low-pressure air. The bottom flow of the flotation unit is the qualified positive selection concentrate.

[0039] In the reverse flotation selection operation, the reagents used in the third selection are fatty acid collectors and sodium sulfate inhibitors; the low-pressure air pressure is between 0.03-0.1MPa, and a Roots blower is used for air supply, and the bubble diameter of the low-pressure air is between 1-2mm.

[0040] Through three rounds of concentrating process, the purity of the concentrate is gradually improved. Each round of concentrating makes full use of the action of reagents and the contact of low-pressure air bubbles to further remove residual impurities, increase the proportion of magnesium ore in the concentrate, and ensure high-grade low-silicon and low-calcium products.

[0041] S4. After filtering and dehydrating the qualified positive concentrate obtained by reverse flotation to form a solution, sodium sulfate adjusting agent and polyacrylamide dispersant are added to carry out positive roughing operation; sodium sulfate is added as an adjusting agent to improve the chemical environment of the slurry; polyacrylamide dispersant helps to disperse suspended particles, reduce agglomeration, and improve the effectiveness of subsequent flotation.

[0042] S5. After the roughing, the concentrate enters the concentration process section, where fatty acid collectors are added and the air volume is controlled between 0.2-0.5 cubic meters of air / cubic meter of slurry to obtain a low-silicon and low-calcium primary concentrate powder. Fatty acid collectors are used to further remove impurities during the concentration process, and the flotation conditions are optimized by controlling the air volume to ensure the best contact between bubbles and minerals, thereby improving the quality of the concentrate.

[0043] S6. During the positive selection operation, the foam generated by the flotation unit is scraped out by the double-sided scrapers to the foam tank and merged into the middling ore. The concentrate powder obtained by the positive selection flows through the pipeline to the dehydration operation for dehydration treatment, and the dehydrated concentrate powder enters the warehouse and is supplied to the downstream workshop as raw material.

[0044] The overall flotation operation uses an aerated stirring flotation machine, which improves efficiency by pressing in enough low-pressure air. After one roughing, three fines, four reverse flotations and one roughing, two fines, and positive flotation reagents, the silicon and calcium content in the magnesite is effectively reduced, the MgO content in the magnesite is increased, the resource utilization in the magnesite field is increased, and the waste of magnesite resources is avoided.

[0045] Embodiment 2: With the continuous reduction of magnesite resources, high-silicon and high-calcium magnesite has gradually become the main raw material of magnesite beneficiation plants. The original indicators of the ore are: MgO content 44.11%, CaO content 1.6%, SiO2 content 5.18%, Fe3O4 content 0.27%. After the flotation purification practice application method disclosed in Embodiment 1, the obtained product indicators are: MgO content 47.78%, CaO content 0.52%, SiO2 content 0.17%, Fe3O4 content 0.29%; through this process, the silicon and calcium content in magnesite is effectively reduced, and the grade of magnesite is improved.

[0046] Importantly, it should be noted that the construction and arrangement of the present application shown in a plurality of different exemplary embodiments are only exemplary. Although only a few embodiments are described in detail in this disclosure, it should be readily understood by those who refer to this disclosure that many modifications are possible (e.g., the size, scale, structure, shape and proportion of various elements and parameter values ​​(e.g., temperature, pressure, etc.), installation arrangement, use of materials, color, directional changes, etc.) without substantially departing from the novel teachings and advantages of the subject matter described in the application. For example, the element shown as integrally formed can be composed of multiple parts or elements, the position of the element can be inverted or otherwise changed, and the nature or number or position of the discrete element can be changed or changed. Therefore, all such modifications are intended to be included in the scope of the present invention. The order or sequence of any process or method steps can be changed or reordered according to alternative embodiments. In the claims, any "device plus function" clause is intended to cover the structure described herein that performs the function, and is not only structurally equivalent but also equivalent structure. Without departing from the scope of the present invention, other replacements, modifications, changes and omissions can be made in the design, operating conditions and arrangement of the exemplary embodiments. Therefore, the invention is not limited to a specific embodiment, but extends to numerous modifications still falling within the scope of the appended claims.

[0047] Additionally, in order to provide a concise description of exemplary embodiments, all features of an actual embodiment (ie, those features that are not relevant to the best mode presently contemplated for carrying out the invention or those that are not relevant to implementing the invention) may not be described.

[0048] It should be understood that in the development of any actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort may be complex and time-consuming, but for those of ordinary skill having the benefit of this disclosure, without undue experimentation, the development effort will be a routine task of design, fabrication, and production.

[0049] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A practical application method for flotation purification of high-silicon and high-calcium magnesite, characterized in that: The following steps are involved: S1, crushing, screening, grinding and grading the raw magnesite; S2. The magnesite ore of qualified particle size is fully mixed with the reagent and flows through the pipeline to the flotation unit for reverse flotation and rough washing; S3, reverse flotation and selection are carried out through three groups of flotation units, and the reagents are fully reacted before each selection; S4, filtering and dehydrating the qualified positive concentrate obtained by reverse flotation to prepare a solution, adding a regulator and a dispersant, and performing positive roughing operation; S5. The concentrate after roughing is sent to the concentration process section, where a collector is added and the air volume is controlled to obtain a low-silicon and low-calcium primary concentrate powder; S6. Dehydrate the concentrate powder obtained from the positive selection, and send the dehydrated concentrate powder to the warehouse to supply it to the downstream workshop as raw material.

2. A practical application method for flotation purification of high-silicon and high-calcium magnesite as claimed in claim 1, characterized in that: In the step S1, the ore is classified after grinding to obtain a selected particle size of -200 mesh accounting for 75%.

3. A practical application method for flotation purification of high-silicon and high-calcium magnesite as claimed in claim 1, characterized in that: In the step S2, the bottom flow of the flotation unit is a roughing concentrate, which flows to the intermediate box by gravity, and the reagent is a fatty acid collector or an amine collector.

4. A practical application method for flotation purification of high-silicon and high-calcium magnesite as claimed in claim 1, characterized in that: The reverse flotation operations in step S3 are respectively concentrating I, concentrating II and concentrating III, and the bottom flow of the flotation unit is the concentrate of each concentrating; The reverse flotation selection I is to make the roughing concentrate flow to the first group of flotation units after the roughing concentrate fully reacts with the reagent in the intermediate box, and fully contact with the low-pressure air. The bottom flow of the flotation unit is the selection I concentrate, which flows to the intermediate box by gravity. The reverse flotation selection II is to react the selected I concentrate with the reagent, and then flow to the second group of flotation units, fully contact with low-pressure air, and the bottom flow of the flotation unit is the selected II concentrate, which flows to the middle box by gravity; The reverse flotation selection III is to react the selected II concentrate with reagents, and then flow to the third group of flotation units to fully contact with low-pressure air. The bottom flow of the flotation unit is a qualified positive selection concentrate.

5. A practical application method for flotation purification of high-silicon and high-calcium magnesite as claimed in claim 4, characterized in that: In the reverse flotation selection operation, the reagents used in the third selection are fatty acid collectors and sodium sulfate inhibitors; the low-pressure air pressure is between 0.03-0.1MPa, and a Roots blower is used for air supply, and the bubble diameter of the low-pressure air is between 1-2mm.

6. A practical application method for flotation purification of high-silicon and high-calcium magnesite as claimed in claim 1, characterized in that: The adjusting agent added in step S4 is sodium sulfate, and the dispersing agent is polyacrylamide; The collector in step S5 is a fatty acid collector, and the air volume is controlled between 0.2-0.5 cubic meters of air / cubic meters of slurry.

7. A practical application method for flotation purification of high-silicon and high-calcium magnesite as claimed in claim 1, characterized in that: In the step S6, the foam generated by the flotation unit during the positive selection operation is scraped out by the double-sided scrapers to the foam tank, merged into the middlings, and flows through the pipeline to the dehydration operation for treatment.

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