Method and system for purifying zinc sulfide ore based on plasma technology

Abstract

The invention discloses a zinc sulfide ore purification method and system based on a plasma technology in the field of ore purification. The zinc sulfide ore purification method comprises the following steps that S10, zinc sulfide ore is crushed to 100-200 meshes; and S20, the crushed zinc sulfide ore is subjected to pre-oxidation treatment. Compared with a traditional method, the method has the advantages that generation of acid leaching wastewater and emission of a large amount of SO2 in the high-temperature calcination process are avoided, pollution to the environment is remarkably reduced, the concept of green chemistry and sustainable development is met, and through the synergistic effect of the plasma-chemical coupling reaction, the gradient temperature field design, the impurity in-situ adsorption and other technologies, the high-temperature calcination process is achieved. The method has the advantages that impurities can be efficiently removed, particularly, the removal effect on trace heavy metal impurities is remarkable, the purity of a final product is greatly improved, the equipment investment and the operation complexity are reduced through the simplified technological process, and therefore the production cost is reduced, and the economic benefits and the market competitiveness of enterprises are improved.

Description

Technical Field

[0001] The present invention relates to the field of ore purification, and specifically to a method and system for purifying zinc sulfide ore based on plasma technology. Background Art

[0002] In the traditional field of purifying zinc sulfide (ZnS), methods such as flotation, acid leaching, and high-temperature calcination have long dominated, but these methods have many defects that cannot be ignored:

[0003] 1) Serious environmental pollution problems: Acid leaching produces a large amount of wastewater containing heavy metal ions and acidic substances during the purification process. If directly discharged without proper treatment, it will cause serious pollution to the ecological environment such as soil and water bodies, threatening the survival of surrounding organisms and human health. The high-temperature calcination process not only consumes huge amounts of energy, but also releases a large amount of SO2 gas, which is one of the important inducements for the formation of acid rain and has an adverse impact on the atmospheric environment.

[0004] 2) Low purification efficiency: Traditional methods are not thorough enough in separating impurities. Especially when facing trace heavy metal impurities such as Pb and Fe, it is difficult to remove them. This results in the purity of the final purified product being difficult to reach a high standard and unable to meet some industrial application scenarios with strict requirements for the purity of zinc sulfide, such as the electronics and optics fields.

[0005] 3) High costs: The multi-step treatment process significantly increases the equipment investment cost. At the same time, the operation process is complex and requires a large amount of manpower and material resources, further driving up the production cost. This not only limits the economic benefits of enterprises, but also restricts the development of the zinc sulfide-related industries to a certain extent.

[0006] In recent years, plasma technology has gradually attracted attention due to its unique advantages. Plasma is rich in high-energy active particles such as electrons and ions. These particles can selectively decompose the mineral lattice to achieve the removal of impurities, featuring low temperature and high efficiency, and also having great potential in environmental protection. However, up to now, there has not been a mature solution to systematically apply plasma technology to zinc sulfide purification.

[0007] Therefore, those skilled in the art have provided a method and system for purifying zinc sulfide ore based on plasma technology to solve the problems raised in the above background art. Summary of the Invention

[0008] The purpose of the present invention is to provide a method and system for purifying zinc sulfide ore based on plasma technology to solve the problems raised in the above background art.

[0009] To achieve the above purpose, the present invention provides the following technical solutions:

[0010] A purification method and system for zinc sulfide ore based on plasma technology, comprising the following steps:

[0011] Step S10: Crush the zinc sulfide ore to 100 - 200 mesh;

[0012] Step S20: Perform pre - oxidation treatment on the crushed zinc sulfide ore. The pre - oxidation treatment temperature is 300 - 400 °C, and O2 is introduced to convert FeS2 into Fe3O4;

[0013] Step S30: Place the pre - oxidized ore powder in a radio - frequency plasma reaction chamber with an Ar / H2 mixed - gas atmosphere. The reaction temperature is 800 - 950 °C, and the treatment is carried out for 10 - 60 minutes;

[0014] Step S40: Perform eddy - current separation on the treated product to obtain ZnS with a purity of ≥99.5% and impurity Pb and Fe contents of <50 ppm.

[0015] As a further scheme of the present invention: In step S20, the flow rate of O2 introduced is 0.5 - 2 L / min.

[0016] As a still further scheme of the present invention: In step S30, the volume ratio of the Ar / H2 mixed - gas is 9:1, the frequency of the plasma radio - frequency power supply is 13.56 MHz, and the power is 5 - 10 kW.

[0017] A purification system for zinc sulfide ore based on plasma technology, comprising a pre - oxidation furnace, a radio - frequency plasma reaction chamber, and an eddy - current separator.

[0018] As a still further scheme of the present invention: The pre - oxidation furnace is used to perform pre - oxidation treatment on the crushed zinc sulfide ore; the radio - frequency plasma reaction chamber is internally provided with an annular electrode array for generating radio - frequency plasma to treat the ore powder; the eddy - current separator is used to separate the treated product to obtain a high - purity zinc sulfide product.

[0019] Compared with the prior art, the beneficial effects of the present invention are:

[0020] Compared with the traditional method, the present invention avoids the generation of acid - leaching wastewater and the emission of a large amount of SO2 during high - temperature calcination, significantly reduces environmental pollution, conforms to the concepts of green chemistry and sustainable development. Through the synergistic effect of technologies such as plasma - chemical coupling reaction, gradient temperature field design, and in - situ impurity adsorption, it can achieve efficient removal of impurities, especially has a significant effect on the removal of trace heavy - metal impurities, greatly improves the purity of the final product, simplifies the process flow, reduces equipment investment and operation complexity, thereby reducing production costs and improving the economic benefits and market competitiveness of enterprises. Specific embodiments

[0021] Next, in combination with the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0022] In an embodiment of the present invention, a purification method and system for zinc sulfide ore based on plasma technology includes the following steps:

[0023] Step S10: Crush the zinc sulfide ore to 100 - 200 mesh;

[0024] Step S20: Perform pre - oxidation treatment on the crushed zinc sulfide ore. The pre - oxidation treatment temperature is 300 - 400 °C, and O2 is introduced to convert FeS2 into Fe3O4;

[0025] Step S30: Place the pre - oxidized ore powder in a radio - frequency plasma reaction chamber with an Ar / H2 mixed - gas atmosphere. The reaction temperature is 800 - 950 °C, and the treatment is carried out for 10 - 60 minutes;

[0026] Step S40: Perform eddy - current separation on the treated product to obtain a high - purity zinc sulfide product.

[0027] Among them, the flow rate of O2 introduced in step S20 is 0.5 - 2 L / min, the volume ratio of the Ar / H2 mixed - gas in step S30 is 9:1, the frequency of the plasma radio - frequency power supply is 13.56 MHz, and the power is 5 - 10 kW.

[0028] A purification system for zinc sulfide ore based on plasma technology includes a pre - oxidation furnace, a radio - frequency plasma reaction chamber, and an eddy - current separator. The pre - oxidation furnace is used to perform pre - oxidation treatment on the crushed zinc sulfide ore; an annular electrode array is arranged inside the radio - frequency plasma reaction chamber, which is used to generate radio - frequency plasma to process the ore powder; the eddy - current separator is used to separate the treated product to obtain a high - purity zinc sulfide product.

[0029] Example 1

[0030] A certain amount of zinc sulfide ore was selected and crushed to 100 mesh. In a pre-oxidation furnace, the temperature was set at 300 °C, and O2 was introduced at a flow rate of 0.5 L / min to pre-oxidize the zinc sulfide ore for 1 hour, enabling FeS2 to be fully converted into Fe3O4. The pre-oxidized ore powder was fed into a plasma reaction chamber, and an Ar / H2 mixed gas (volume ratio 9:1) was introduced. A radio frequency power supply (frequency 13.56 MHz, power 5 kW) was used to excite the plasma, maintaining the reaction zone temperature at 800 °C for a reaction time of 60 minutes. After the reaction, the product was separated by eddy current separation, and the purity of the final zinc sulfide product reached 99.5%, with the impurity Pb and Fe contents being 45 ppm and 48 ppm respectively.

[0031] Example 2

[0032] The same type of zinc sulfide ore was taken and crushed to 200 mesh. In the pre-oxidation stage, the temperature was raised to 400 °C, the O2 flow rate was adjusted to 2 L / min, and the treatment time was 0.5 hour. In the plasma reaction chamber, the radio frequency power supply power was increased to 10 kW, the reaction temperature was controlled at 950 °C, and the reaction time was shortened to 10 minutes. After eddy current separation, the purity of the zinc sulfide product reached 99.6%, and the impurity Pb and Fe contents were both less than 50 ppm.

[0033] Example 3

[0034] Another batch of zinc sulfide ore was selected and crushed to 150 mesh. The pre-oxidation temperature was set at 350 °C, the O2 flow rate was 1 L / min, and the treatment was carried out for 0.8 hour. During the plasma reaction, the radio frequency power supply frequency of 13.56 MHz was maintained unchanged, the power was 7.5 kW, the reaction zone temperature was kept at 880 °C, and the reaction time was 30 minutes. The purity of the finally obtained zinc sulfide product was 99.55%, and the impurity Pb and Fe contents were 42 ppm and 46 ppm respectively.

[0035] It can be seen from the above Examples 1 - 3 that the purification method and system of the present invention can stably obtain high-purity zinc sulfide products under different process parameter conditions, effectively verifying its feasibility and reliability.

[0036] Compared with the traditional method, the present invention avoids the generation of acid leaching wastewater and the emission of a large amount of SO2 during high-temperature calcination, significantly reducing environmental pollution, conforming to the concepts of green chemistry and sustainable development. Through the synergistic effect of technologies such as plasma-chemical coupling reaction, gradient temperature field design, and in-situ impurity adsorption, efficient removal of impurities can be achieved, especially the removal effect of trace heavy metal impurities is remarkable, greatly improving the purity of the final product. The simplified process flow reduces equipment investment and operation complexity, thereby reducing production costs and enhancing the economic benefits and market competitiveness of enterprises.

[0037] As described above, it is only the preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, making equivalent substitutions or changes should be covered within the protection scope of the present invention.

Claims

1. A purification method for zinc sulfide ore based on plasma technology, characterized in that: It includes the following steps: Step S10: Crush zinc sulfide ore to 100 - 200 mesh; Step S20: Perform pre - oxidation treatment on the crushed zinc sulfide ore. The pre - oxidation treatment temperature is 300 - 400 °C, introduce O2, and convert FeS2 into Fe3O4; Step S30: Place the pre - oxidized ore powder in a radio - frequency plasma reaction chamber with an Ar / H2 mixed - gas atmosphere. The reaction temperature is 800 - 950 °C, and treat for 10 - 60 minutes; Step S40: Perform eddy - current separation on the treated product to obtain a high - purity zinc sulfide product.

2. The purification method of zinc sulfide ore based on plasma technology according to claim 1, characterized in that: In step S20, the flow rate of the introduced O2 is 0.5 - 2 L / min.

3. A purification method of zinc sulfide ore based on plasma technology according to claim 1, characterized in that: In step S30, the volume ratio of the Ar / H2 mixed - gas is 9:1, the frequency of the plasma radio - frequency power supply is 13.56 MHz, and the power is 5 - 10 kW.

4. A purification system for zinc sulfide ore based on plasma technology, which applies a purification method for zinc sulfide ore based on plasma technology as described in any one of claims 1-3, characterized in that: It includes a pre - oxidation furnace, a radio - frequency plasma reaction chamber, and an eddy - current separator.

5. A zinc sulfide ore purification system based on plasma technology according to claim 4, characterized in that: The pre - oxidation furnace is used to perform pre - oxidation treatment on the crushed zinc sulfide ore; the radio - frequency plasma reaction chamber is internally provided with an annular electrode array for generating radio - frequency plasma to treat the ore powder; the eddy - current separator is used to separate the treated product to obtain a high - purity zinc sulfide product.