A device and method for purifying quartz sand by high-temperature chlorination of mixed acid solution

Abstract

The present invention relates to a device and method for purifying quartz sand by high-temperature chlorination of mixed acid solution. The present invention comprises a heating reaction mechanism, which comprises a No. 1 quartz heating tube, a first transmission system, a No. 1 furnace for heating the No. 1 quartz heating tube, and a first temperature control system for controlling the heating temperature of the No. 1 furnace. The two nozzles of the No. 1 quartz heating tube are respectively a No. 1 quartz sand inlet and a No. 1 quartz sand outlet. The present invention also comprises a preheating mechanism and an acid solution mixing and adding mechanism. The preheating mechanism comprises a No. 2 quartz heating tube, a second transmission system, and a second temperature control system. The two nozzles of the No. 2 quartz heating tube are respectively a No. 2 quartz sand inlet and a No. 2 quartz sand outlet. The acid solution mixing and adding mechanism comprises a pulse conveying assembly, a first funnel assembly, and a second funnel assembly. The present invention can purify quartz sand safely and effectively.

Description

Technical Field

[0001] The invention relates to the technical field of quartz sand production, in particular to a device and method for purifying quartz sand by high-temperature chlorination of mixed acid solution. Background Art

[0002] In recent years, in order to improve the quality and output of Czochralski single crystal silicon, continuous feeding, multiple feeding and other technologies for growing multiple Czochralski single crystal silicon in one furnace have been developed and applied. In Czochralski single crystal silicon, the one-time consumption of quartz crucibles and the time-consuming disassembly and assembly of furnaces account for a high proportion of the cost. Under the traditional Czochralski method, the quartz crucible can only be used once and can only produce one crystal rod at a time. The continuous Czochralski method can continuously add materials to the quartz crucible during the crystal pulling process and continuously produce multiple new crystal rods, which puts higher requirements on the life of the quartz crucible. The long-life quartz crucible developed by domestic enterprises can continuously pull crystals for more than 200 hours, and the service quality (life) of the quartz crucible is ultimately determined by the purity of its raw material high-purity quartz sand, that is, the purity of high-purity quartz sand is ≥99.998%, and the total impurity element content is <20PPM, especially the sum of alkaline earth metal elements K, Na, and Li is ≤3PPM.

[0003] Since domestic quartz sand contains many inclusions, it is impossible to remove the impurities in the quartz inclusions by only relying on flotation, pickling and other treatment processes. At present, the high-temperature chlorination devices used for the purification of high-purity quartz sand all use bottled chlorine and hydrogen chloride gases. Poor control of transportation, storage and production processes will cause gas leakage, directly endangering human life and causing environmental pollution. In addition, quartz sand reacts with gas in a static manner, resulting in insufficient reaction and failure to form continuous production, which brings a series of safety, quality, cost and other problems. Therefore, how to purify quartz sand safely and effectively is a problem that needs to be solved urgently by technicians in this field. Summary of the invention

[0004] To this end, the technical problem to be solved by the present invention is to overcome the problem that in the process of quartz sand production in the prior art, quartz sand and chlorine do not react sufficiently, cannot form continuous production, and bring about a series of safety, quality, cost and other problems.

[0005] In order to solve the above technical problems, the present invention provides a device for purifying quartz sand by high-temperature chlorination of mixed acid solution, comprising a heating reaction mechanism, wherein the heating reaction mechanism comprises a No. 1 quartz heating tube for providing a heating reaction space for quartz sand and chlorine, a first transmission system for driving the No. 1 quartz heating tube to rotate around its own longitudinal axis, a No. 1 furnace for heating the No. 1 quartz heating tube, and a first temperature control system for controlling the heating temperature of the No. 1 furnace, wherein the No. 1 quartz heating tube is rotatably arranged in the No. 1 furnace around its longitudinal axis, and the two tube openings of the No. 1 quartz heating tube are respectively a No. 1 quartz sand inlet and a No. 1 quartz sand outlet, and further comprises a preheating mechanism and an acid solution mixing and adding mechanism, wherein the preheating mechanism comprises a No. 2 quartz heating tube for providing a heating space for quartz sand, a second transmission system for driving the No. 2 quartz heating tube to rotate around its own longitudinal axis, and a first temperature control system for controlling the heating temperature of the No. 1 furnace. The invention relates to a driving system, a No. 2 furnace for heating the No. 2 quartz heating tube, and a second temperature control system for controlling the heating temperature of the No. 2 furnace. The two pipe openings of the No. 2 quartz heating tube are respectively a No. 2 quartz sand inlet and a No. 2 quartz sand outlet. The acid mixing and adding mechanism comprises a pulse conveying component for pulse outputting mixed acid, a first funnel component for adding concentrated hydrochloric acid into the pulse conveying component, and a second funnel component for adding concentrated nitric acid into the pulse conveying component. The No. 2 quartz sand outlet is connected to the No. 1 quartz sand inlet. The mixed acid outlet of the pulse conveying component is connected to the No. 1 quartz heating tube from one of the pipe openings of the No. 1 quartz heating tube. One of the pipe openings of the No. 2 quartz heating tube and the mixed acid outlet of the pulse conveying component are respectively connected to one of the pipe openings of the No. 1 quartz heating tube.

[0006] Furthermore, the first funnel assembly includes a first funnel and a first quartz funnel outlet tube connected to the outlet of the first funnel, the second funnel assembly includes a second funnel and a second quartz funnel outlet tube connected to the outlet of the second funnel, the pulse delivery assembly includes a peristaltic pump and a pump outlet tube connected to the outlet of the peristaltic pump, the outlet of the first quartz funnel outlet tube and the outlet of the second quartz funnel outlet tube are connected to the inlet of the peristaltic pump, and the outlet of the pump outlet tube extends into the No. 1 quartz sand outlet.

[0007] Furthermore, the No. 1 quartz heating tube is provided with two No. 1 quartz leakage baffles respectively close to its two tube openings, and the No. 2 quartz heating tube is provided with two No. 2 quartz leakage baffles respectively close to its two tube openings, the leakage holes of the No. 1 quartz leakage baffle and the No. 2 quartz leakage baffle allow quartz sand to pass through, and the entity of the No. 1 quartz leakage baffle and the entity of the No. 2 quartz leakage baffle are used to buffer the hot air flow.

[0008] Furthermore, a quartz scraper is provided on the inner side wall of the No. 1 quartz heating tube, and the quartz scraper is used to stir the material in the No. 1 quartz heating tube.

[0009] Furthermore, the No. 1 quartz heating tube and the No. 2 quartz heating tube are tilted, and the tilt angles of the No. 1 quartz heating tube and the No. 2 quartz heating tube are 1 degree-2 degrees. The No. 1 quartz sand inlet is upturned, and the No. 1 quartz sand outlet is drooping. The No. 2 quartz sand inlet is upturned, and the No. 2 quartz sand outlet is drooping.

[0010] Furthermore, an air suction hood is provided at the junction of the No. 1 quartz sand inlet and the No. 2 quartz sand outlet, and at the No. 1 quartz sand outlet and the No. 2 quartz sand inlet.

[0011] Furthermore, each of the No. 1 furnace and the No. 2 furnace includes a furnace body, an inner side wall of the furnace body is provided with an aluminum silicate ceramic wool insulation layer, and an inner side wall of the aluminum silicate ceramic wool insulation layer is provided with silicon-molybdenum rods.

[0012] A method for purifying quartz sand by high-temperature chlorination of mixed acid solution comprises the following steps:

[0013] S1, concentrated hydrochloric acid and concentrated nitric acid are mixed in a set volume ratio to obtain a mixed acid solution, and the mixed acid solution is pulsed into a high-temperature reaction zone, where the mixed acid solution generates high-concentration chlorine gas;

[0014] S2, calcining the quartz sand with surface impurities pre-treated in a high temperature zone to obtain calcined quartz sand, and sending the calcined quartz sand into a high temperature reaction zone;

[0015] S3, the quartz sand is tumbled evenly after calcination, and the impurities in the quartz sand are fully contacted with the chlorine to react to generate gaseous chlorides, and the high-temperature airflow takes away the chlorides containing impurity elements, thereby completing the purification of the quartz sand;

[0016] There is no particular order for steps S1 and S2, and the temperature of the high-temperature reaction zone is higher than the temperature of the high-temperature zone.

[0017] Furthermore, in step S1, the set volume is 3:1.

[0018] Furthermore, in step S1, the temperature of the high temperature reaction zone is 1350°C-1500°C, and the temperature of the high temperature zone is 900°C-1100°C.

[0019] The above technical solution of the present invention has the following advantages compared with the prior art:

[0020] 1) The device for purifying quartz sand by high-temperature chlorination of mixed acid solution disclosed in the present invention utilizes a mixed acid solution composed of concentrated hydrochloric acid and concentrated nitric acid to produce high-concentration chlorine gas, which can ensure the concentration of chlorine gas and the acquisition method is safe.

[0021] 2) The device for purifying quartz sand by high-temperature chlorination of mixed acid disclosed in the present invention adopts a segmented structure to separate the calcination zone and the reaction zone, and each quartz tube has a silicon nitride coating inside and outside, which greatly improves the purity and production efficiency of the quartz sand, further increases the service life and reduces the maintenance cost.

[0022] 3) The device for purifying quartz sand by high-temperature chlorination of mixed acid disclosed in the present invention has an air suction hood installed at the inlet and outlet to recycle and process the waste gas, thereby avoiding pollution to the environment, reducing gas waste, and effectively saving resources and costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below according to specific embodiments of the present invention in conjunction with the accompanying drawings, wherein:

[0024] Figure 1 The present invention is a structural diagram of a device for purifying quartz sand by high-temperature chlorination of mixed acid solution.

[0025] Explanation of the reference numerals in the specification: 10. Quartz heating tube No. 1; 11. Furnace No. 1; 12. First transmission system; 13. Quartz sand inlet No. 1; 14. Quartz sand outlet No. 1; 15. Quartz leak baffle No. 1; 16. Quartz scraper; 17. Aluminum silicate ceramic wool insulation layer; 18. Silicon molybdenum rod; 20. Quartz heating tube No. 2; 21. Furnace No. 2; 22. Second transmission system; 23. Quartz sand inlet No. 2; 24. Quartz sand outlet No. 2; 25. Quartz leak baffle No. 2; 30. First funnel; 31. First quartz funnel outlet pipe; 40. Second funnel; 41. Second quartz funnel outlet pipe; 50. Peristaltic pump; 60. Suction hood. DETAILED DESCRIPTION

[0026] The specific implementation of the present invention is further described in detail below in conjunction with the drawings and examples.

[0027] It should be noted that the following detailed descriptions are exemplary and are intended to provide further improved descriptions for the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those generally understood by those of ordinary skill in the art to which the present application belongs. It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context otherwise clearly indicates, the singular form is also intended to include the plural form. In addition, it should also be understood that when the terms "include" and / or "include" are used in this specification, it indicates that there are features, steps, operations, devices, components and / or combinations thereof. In the present disclosure, the orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "front", "back", "vertical", "horizontal", "side", "bottom" etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only a relationship word determined for the convenience of describing the structural relationship of each component or element of the present disclosure, and does not specifically refer to any component or element in the present disclosure, and cannot be understood as a limitation to the present disclosure. In the present disclosure, terms such as "fixed connection", "connected", "connection", etc. should be understood in a broad sense, indicating that it can be fixedly connected, integrally connected or detachably connected; it can be directly connected or indirectly connected through an intermediate medium. For relevant scientific research or technical personnel in this field, the specific meanings of the above terms in the present disclosure can be determined according to specific circumstances, and they cannot be understood as limitations on the present disclosure.

[0028] Reference Figure 1As shown in the figure, a device for purifying quartz sand by high-temperature chlorination of mixed acid solution comprises a heating reaction mechanism, wherein the heating reaction mechanism comprises a No. 1 quartz heating tube 10 for providing a heating reaction space for quartz sand and chlorine gas, a first transmission system 11 for driving the No. 1 quartz heating tube 10 to rotate around its own longitudinal axis, a No. 1 furnace 12 for heating the No. 1 quartz heating tube 10, and a first temperature control system for controlling the heating temperature of the No. 1 furnace 12, wherein the No. 1 quartz heating tube 10 is rotatably arranged in the No. 1 furnace 12 around its longitudinal axis, and the two pipe openings of the No. 1 quartz heating tube 10 are respectively a No. 1 quartz sand inlet 13 and a No. 1 quartz sand outlet 14, and further comprises a preheating mechanism and an acid solution mixing and adding mechanism, wherein the preheating mechanism comprises a No. 2 quartz heating tube 20 for providing a heating space for quartz sand, a second transmission system 11 for driving the No. 2 quartz heating tube 20 to rotate around its own longitudinal axis, and a first temperature control system for controlling the heating temperature of the No. 1 furnace 12. System 21, a No. 2 furnace 22 for heating the No. 2 quartz heating tube 20 and a second temperature control system for controlling the heating temperature of the No. 2 furnace 22, the two pipe openings of the No. 2 quartz heating tube 20 are respectively a No. 2 quartz sand inlet 23 and a No. 2 quartz sand outlet 24, the acid liquid mixing and adding mechanism comprises a pulse conveying component for pulse outputting mixed acid liquid, a first funnel component for adding concentrated hydrochloric acid into the pulse conveying component and a second funnel component for adding concentrated nitric acid into the pulse conveying component, the No. 2 quartz sand outlet 24 is connected to the No. 1 quartz sand inlet 13, the mixed acid liquid outlet of the pulse conveying component is connected to the No. 1 quartz heating tube 10 from one of the pipe openings of the No. 1 quartz heating tube 10, and one of the pipe openings of the No. 2 quartz heating tube 20 and the mixed acid liquid outlet of the pulse conveying component are respectively connected to one of the pipe openings of the No. 1 quartz heating tube 10.

[0029] In the above, a device for purifying quartz sand by high-temperature chlorination of mixed acid solution is provided, which adopts a segmented structure, separates the calcination zone and the reaction zone, and each quartz heating tube has a silicon nitride coating inside and outside, and uses a mixed acid solution composed of concentrated hydrochloric acid and concentrated nitric acid to produce high-concentration chlorine gas. It solves the safety and cost deficiencies of the existing high-temperature chlorination technology, is convenient and easy to form large-scale industrial production, greatly improves the purity and production efficiency of quartz sand, and reduces safety hazards and maintenance and use costs.

[0030] In the preferred implementation manner of this embodiment, the above-mentioned first funnel assembly includes a first funnel 30 and a first quartz funnel outlet tube 31 connected to the outlet of the above-mentioned first funnel, the above-mentioned second funnel assembly includes a second funnel 40 and a second quartz funnel outlet tube 41 connected to the outlet of the above-mentioned second funnel, the above-mentioned pulse delivery assembly includes a peristaltic pump 50 and a pump outlet tube connected to the outlet of the above-mentioned peristaltic pump, the outlet of the outlet tube of the above-mentioned first quartz funnel 30 and the outlet of the outlet tube of the above-mentioned second quartz funnel 40 are connected to the inlet of the above-mentioned peristaltic pump 50, and the outlet of the above-mentioned pump outlet tube extends into the above-mentioned No. 1 quartz sand outlet 14.

[0031] In the preferred implementation manner of the present embodiment, the No. 1 quartz heating tube 10 is provided with two No. 1 quartz leak baffles 15 respectively close to its two tube openings, and the No. 2 quartz heating tube 20 is provided with two No. 2 quartz leak baffles 24 respectively close to its two tube openings, the leak holes of the No. 1 quartz leak baffle 15 and the No. 2 quartz leak baffle 25 allow quartz sand to pass through, and the entity of the No. 1 quartz leak baffle 15 and the entity of the No. 2 quartz leak baffle 25 are used to buffer the hot gas flow.

[0032] In the above, the quartz leak baffle can buffer the dissipation of hot air flow and keep it warm.

[0033] In a preferred implementation manner of the present embodiment, a quartz scraper 16 is provided on the inner side wall of the No. 1 quartz heating tube 10 , and the quartz scraper 16 is used to stir the material in the No. 1 quartz heating tube 10 .

[0034] In the above, a quartz scraper sprayed with a silicon nitride coating is arranged in the quartz heating tube so that the material can be evenly heated in the quartz heating tube.

[0035] In the preferred implementation manner of the present embodiment, the No. 1 quartz heating tube 10 and the No. 2 quartz heating tube 20 are tilted, and the tilt angles of the No. 1 quartz heating tube 10 and the No. 2 quartz heating tube 20 are 1 degree to 2 degrees, the No. 1 quartz sand inlet 13 is upturned, the No. 1 quartz sand outlet 14 is drooping, the No. 2 quartz sand inlet 23 is upturned, and the No. 2 quartz sand outlet 24 is drooping.

[0036] In a preferred implementation manner of the present embodiment, a suction hood 60 is provided at the junction of the No. 1 quartz sand inlet 13 and the No. 2 quartz sand outlet 24 , the No. 1 quartz sand outlet 14 , and the No. 2 quartz sand inlet 23 .

[0037] In the above, suction hoods are installed at the inlet and outlet to recycle the waste gas, avoiding pollution to the environment, reducing gas waste, and effectively saving resources and costs.

[0038] In the preferred implementation manner of the present embodiment, each of the above-mentioned furnace No. 12 and the above-mentioned furnace No. 2 22 includes a furnace body, and the inner side wall of the above-mentioned furnace body is provided with an aluminum silicate ceramic wool insulation layer 17, and the inner side wall of the above-mentioned aluminum silicate ceramic wool insulation layer 17 is provided with silicon molybdenum rods 18.

[0039] A method for purifying quartz sand by high-temperature chlorination of mixed acid solution comprises the following steps:

[0040] S1, concentrated hydrochloric acid and concentrated nitric acid are mixed in a set volume ratio to obtain a mixed acid solution, and the mixed acid solution is pulsed into a high-temperature reaction zone, where the mixed acid solution generates high-concentration chlorine gas;

[0041] S2, calcining the quartz sand with surface impurities pre-treated in a high temperature zone to obtain calcined quartz sand, and sending the calcined quartz sand into a high temperature reaction zone;

[0042] S3, the quartz sand is tumbled evenly after calcination, and the impurities in the quartz sand are fully contacted with the chlorine to react to generate gaseous chlorides, and the high-temperature airflow takes away the chlorides containing impurity elements, thereby completing the purification of the quartz sand;

[0043] There is no particular order for steps S1 and S2, and the temperature of the high-temperature reaction zone is higher than the temperature of the high-temperature zone.

[0044] In the preferred implementation manner of this embodiment, in step S1, the set volume is 3:1.

[0045] In a preferred implementation manner of this embodiment, in step S1, the temperature of the high temperature reaction zone is 1350°C-1500°C, and the temperature of the high temperature zone is 900°C-1100°C.

[0046] In the above, the device of the present invention uses a mixed acid solution composed of concentrated hydrochloric acid and concentrated nitric acid in a volume ratio of 3:1, and transports the mixed acid solution to the No. 1 quartz heating tube 10 that runs through the No. 1 furnace 12 through a pulse conveying component, generating high-concentration gaseous chlorine at high temperature, and the high-concentration chlorine is calcined with the quartz sand in the No. 1 quartz heating tube 10 at high temperature. Under high temperature conditions, the pressure difference between the inside and outside of the quartz sand inclusions is further increased, so that the gas-liquid inclusions in the quartz sand are broken, and the quartz particles in the tube are rolled by rotating the quartz scraper 16 on the inner wall of the No. 1 quartz heating tube 10, so that the alkali metals, alkaline earth metals and impurities of the explosion diffusion of the inclusions on the surface of the quartz particles are fully contacted and reacted at high temperature to generate gaseous chlorides, and the high-temperature airflow takes away the chlorides of these impurity elements, thereby achieving the purification effect. The device of the present invention is very practical and operable, and it is easy to form large-scale industrial production.

[0047] Obviously, the above embodiments are merely examples for the purpose of clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the present invention.

Claims

1. A device for purifying quartz sand by high-temperature chlorination of mixed acid solution, comprising a heating reaction mechanism, wherein the heating reaction mechanism comprises a No. 1 quartz heating tube for providing a heating reaction space for quartz sand and chlorine gas, a first transmission system for driving the No. 1 quartz heating tube to rotate around its own longitudinal axis, a No. 1 furnace for heating the No. 1 quartz heating tube, and a first temperature control system for controlling the heating temperature of the No. 1 furnace, wherein the No. 1 quartz heating tube is rotatably arranged in the No. 1 furnace around its longitudinal axis, and the two pipe openings of the No. 1 quartz heating tube are respectively a No. 1 quartz sand inlet and a No. 1 quartz sand outlet, wherein the device comprises: It also includes a preheating mechanism and an acid mixing and adding mechanism, the preheating mechanism includes a No. 2 quartz heating tube for providing a heating space for quartz sand, a second transmission system for driving the No. 2 quartz heating tube to rotate around its own longitudinal axis, a No. 2 furnace for heating the No. 2 quartz heating tube, and a second temperature control system for controlling the heating temperature of the No. 2 furnace, the two pipe openings of the No. 2 quartz heating tube are respectively a No. 2 quartz sand inlet and a No. 2 quartz sand outlet, the acid mixing and adding mechanism includes a pulse conveying component for pulse output of mixed acid, a first funnel component for adding concentrated hydrochloric acid to the pulse conveying component, and a second funnel component for adding concentrated nitric acid to the pulse conveying component, the No. 2 quartz sand outlet is connected to the No. 1 quartz sand inlet, the mixed acid outlet of the pulse conveying component is passed into the No. 1 quartz heating tube from one of the pipe openings of the No. 1 quartz heating tube, and one of the pipe openings of the No. 2 quartz heating tube and the mixed acid outlet of the pulse conveying component are respectively connected to one of the pipe openings of the No. 1 quartz heating tube.

2. The device for purifying quartz sand by high temperature chlorination of mixed acid solution according to claim 1, characterized in that: The first funnel assembly includes a first funnel and a first quartz funnel outlet tube connected to the outlet of the first funnel, the second funnel assembly includes a second funnel and a second quartz funnel outlet tube connected to the outlet of the second funnel, the pulse delivery assembly includes a peristaltic pump and a pump outlet tube connected to the outlet of the peristaltic pump, the outlet of the first quartz funnel outlet tube and the outlet of the second quartz funnel outlet tube are connected to the inlet of the peristaltic pump, and the outlet of the pump outlet tube extends into the No. 1 quartz sand outlet.

3. The device for purifying quartz sand by high temperature chlorination of mixed acid solution according to claim 1, characterized in that: The No. 1 quartz heating tube is provided with two No. 1 quartz leakage baffles respectively close to its two tube openings, and the No. 2 quartz heating tube is provided with two No. 2 quartz leakage baffles respectively close to its two tube openings. The leakage holes of the No. 1 quartz leakage baffle and the No. 2 quartz leakage baffle allow quartz sand to pass through, and the entity of the No. 1 quartz leakage baffle and the entity of the No. 2 quartz leakage baffle are used to buffer the hot air flow.

4. The device for purifying quartz sand by high temperature chlorination of mixed acid solution according to claim 1, characterized in that: A quartz scraper is provided on the inner side wall of the No. 1 quartz heating tube, and the quartz scraper is used to stir the material in the No. 1 quartz heating tube.

5. The device for purifying quartz sand by high temperature chlorination of mixed acid solution according to claim 1, characterized in that: The No. 1 quartz heating tube and the No. 2 quartz heating tube are tilted, and the tilt angles of the No. 1 quartz heating tube and the No. 2 quartz heating tube are 1 degree-2 degrees. The No. 1 quartz sand inlet is upturned, and the No. 1 quartz sand outlet is drooping. The No. 2 quartz sand inlet is upturned, and the No. 2 quartz sand outlet is drooping.

6. The device for purifying quartz sand by high temperature chlorination of mixed acid solution according to claim 1, characterized in that: A suction hood is provided at the junction of the No. 1 quartz sand inlet and the No. 2 quartz sand outlet, and at the No. 1 quartz sand outlet and the No. 2 quartz sand inlet.

7. The device for purifying quartz sand by high temperature chlorination of mixed acid solution according to claim 1, characterized in that: Each of the No. 1 furnace and the No. 2 furnace includes a furnace body, an inner side wall of the furnace body is provided with an aluminum silicate ceramic wool insulation layer, and an inner side wall of the aluminum silicate ceramic wool insulation layer is provided with silicon molybdenum rods.

8. A method for purifying quartz sand by high temperature chlorination of mixed acid solution, characterized in that: The following steps are involved: S1, concentrated hydrochloric acid and concentrated nitric acid are mixed in a set volume ratio to obtain a mixed acid solution, and the mixed acid solution is pulsed into a high-temperature reaction zone, where the mixed acid solution generates high-concentration chlorine gas; S2, calcining the quartz sand with surface impurities pre-treated in a high temperature zone to obtain calcined quartz sand, and sending the calcined quartz sand into a high temperature reaction zone; S3, the quartz sand is tumbled evenly after calcination, and the impurities in the quartz sand are fully contacted with the chlorine to react to generate gaseous chlorides, and the high-temperature airflow takes away the chlorides containing impurity elements, thereby completing the purification of the quartz sand; There is no particular order for steps S1 and S2, and the temperature of the high-temperature reaction zone is higher than the temperature of the high-temperature zone.

9. The method for purifying quartz sand by high temperature chlorination of mixed acid solution according to claim 8, characterized in that: In step S1, the set volume is 3:

1.

10. The method for purifying quartz sand by high temperature chlorination of mixed acid solution according to claim 8, characterized in that: In step S1, the temperature of the high temperature reaction zone is 1350°C-1500°C, and the temperature of the high temperature zone is 900°C-1100°C.

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