Hydrogen circulating system for polycrystalline silicon production

Abstract

The invention relates to a hydrogen circulation system for polycrystalline silicon production, which comprises a condensation area and a liquid storage area which are communicated with each other, and mixed gas enters the condensation area for condensation and is discharged from the liquid storage area; condensate is stored in the liquid storage area, and a stirring part for keeping gas and liquid mixed is arranged at the condensation area. According to the invention, the condensation zone and the liquid storage zone are communicated with each other, so that chlorosilane in the mixed gas can be continuously mixed with hydrogen chloride in the mixed gas in the liquid storage zone after condensation is completed, the separation process of chlorosilane and hydrogen chloride can be completed in one process, and the absorption effect on hydrogen chloride is improved.

Description

Technical Field

[0001] The present invention relates to the production of polysilicon, and more particularly to a hydrogen circulation system for polysilicon production. Background Art

[0002] Currently, in the process of producing rod-shaped polysilicon by the improved Siemens method, the unreacted hydrogen comes out of the reduction furnace and the chlorosilane components contained therein are separated by condensation. Subsequently, in the next step, the hydrogen chloride in the hydrogen is further absorbed by liquid chlorosilane. Then, through the adsorption step, the trace chlorosilane, hydrogen chloride and some other component gases in the hydrogen are absorbed by activated carbon, so as to obtain relatively pure hydrogen, which enters the reduction furnace again for recycling;

[0003] Above, in this process, when the chlorosilane is condensed and enters the next step, since it needs to be transferred between equipment, it is easy to cause the temperature to rise during the process, and a small part of the components will be vaporized, thus reducing the absorption effect of hydrogen chloride. Summary of the Invention

[0004] The purpose of this part is to outline some aspects of the embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this part, as well as in the abstract and title of the specification of this application, to avoid obscuring the purpose of this part, the abstract and the title of the invention, and such simplifications or omissions shall not be used to limit the scope of the present invention.

[0005] To solve the problems in the above background art, the present invention provides the following technical solutions:

[0006] A hydrogen circulation system for polysilicon production includes a mutually communicated condensation area and a liquid storage area, wherein:

[0007] The mixed gas enters the condensation area for condensation and is discharged from the liquid storage area;

[0008] The condensate is stored in the liquid storage area, and a stirring part for maintaining gas-liquid mixing is provided at the condensation area.

[0009] As a preferred technical solution of a hydrogen circulation system for polysilicon production, a condensation pipe through which a cooling medium passes is movably arranged in the condensation area, and it is connected to the stirring part.

[0010] As a preferred technical solution of a hydrogen circulation system for polysilicon production, the condensation cavity is circular, and the condensation pipe is rotatably arranged in the condensation cavity.

[0011] As a preferred technical solution of a hydrogen circulation system for polysilicon production, the stirring part is rotatably matched with the inner wall of the condensation cavity.

[0012] As a preferred technical solution of a hydrogen circulation system for polysilicon production, it further includes a rotating block, on which a coaxial and annular first through port and a second through port are constructed. The first through port and the second through port are respectively fixedly communicated with both ends of the condensing pipe. A first port and a second port are fixedly arranged at the condensing area, and are respectively rotationally communicated with the first through port and the second through port.

[0013] As a preferred technical solution of a hydrogen circulation system for polysilicon production, it further includes a first output pipeline and a vaporization chamber. The condensate flows out from the liquid storage area and reaches the vaporization chamber through the first output pipeline. A rotating spray head communicated with the first output pipeline is rotatably arranged in the vaporization chamber, and is in transmission cooperation with the stirring part. The condensate returns to room temperature in the first output pipeline.

[0014] As a preferred technical solution of a hydrogen circulation system for polysilicon production, the condensate forms a heat exchange with the mixed gas during the process of passing through the first output pipeline.

[0015] As a preferred technical solution of a hydrogen circulation system for polysilicon production, it further includes a heat exchanger and an inlet pipeline. The mixed gas reaches the condensing area through the inlet pipeline, and both the inlet pipeline and the first output pipeline pass through the heat exchanger.

[0016] The hydrogen circulation system for polysilicon production provided by the present invention has the following beneficial effects:

[0017] 1. Through the intercommunication setting between the condensing area and the liquid storage area, the chlorosilane in the mixed gas can continue to be mixed with hydrogen chloride in the mixed gas in the liquid storage area after condensation is completed, so that the separation process of chlorosilane and hydrogen chloride can be completed in one process, thereby increasing the absorption effect of hydrogen chloride.

[0018] 2. Through the cooperation of the heat exchanger and the vaporization chamber, the mixed gas discharged from the reduction furnace can be pre-cooled in advance by chlorosilane, thereby reducing the burden of the subsequent condensation process. At the same time, the vaporization effect formed when the chlorosilane returns to room temperature can be used to drive the stirring part to move, so as to reduce the input of kinetic energy in the whole system, thereby saving energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts. Among them:

[0020] Figure 1 It is a schematic diagram of the pipeline connection between some structures in one embodiment of the present invention.

[0021] Figure 2 This is a three-dimensional schematic diagram of part of the structure in one embodiment of the present invention.

[0022] Figure 3 Regarding Figure 2 This is an internal sectional view of part of the structure in

[0023] Figure 4 Regarding Figure 3 This is a sectional view of the section of

[0024] Figure 5 Regarding Figure 3 This is a further three-dimensional cut-away view of part of the structure in

[0025] Figure 6 Regarding Figure 2 This is an internal sectional view of part of the structure in

[0026] Reference numerals:

[0027] 1. Condensation chamber; 2. Vaporization chamber; 3. Inlet pipeline; 4. First output pipeline; 5. Second output pipeline; 6. Condensation area; 7. Liquid storage area; 8. Air inlet; 9. Air outlet; 10. Liquid outlet; 11. Condensation pipe; 12. Stirring part; 13. Rotating block; 14. First through port; 15. Second through port; 16. First port; 17. Second port; 18. Rotary spray head; 19. Inlet. Detailed implementation manners

[0028] To make the above objects, features and advantages of the present invention more obvious and understandable, the following detailed description of the specific implementation manners of the present invention will be given with reference to the accompanying drawings of the specification.

[0029] In the following description, many specific details are set forth to facilitate a thorough understanding of the present invention. However, the present invention may be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0030] Secondly, the so-called "one embodiment" or "embodiment" herein refers to a specific feature, structure or characteristic that may be included in at least one implementation manner of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it an individual or alternative embodiment that is mutually exclusive with other embodiments.

[0031] Next, the present invention will be described in detail with reference to the schematic diagrams. When describing the embodiments of the present invention in detail, for the convenience of explanation, the cross-sectional views showing the device structure will be locally enlarged in a non-general proportion, and the schematic diagrams are only examples and should not limit the scope of protection of the present invention herein. In addition, in actual production, three-dimensional spatial dimensions including length, width, and depth should be included.

[0032] Referring Figure 1-6 , an embodiment of the present invention provides a hydrogen circulation system for polysilicon production. As Figure 1 shown, the system includes an intake pipeline 3, a first output pipeline 4, and a second output pipeline 5. The mixed gas coming out of the reduction furnace enters the condensation chamber 1 through the intake pipeline 3 for final condensation, so that the chlorosilane in the mixed gas condenses into a liquid. The liquid chlorosilane finally enters the vaporization chamber 2 through the second output pipeline 5, and hydrogen enters the subsequent further adsorption link through the second output pipeline 5, thereby obtaining pure hydrogen;

[0033] In this entire system, the specific structure of the condensation chamber 1 is as Figure 1-4 shown. Its interior can be divided into a condensation area 6 and a liquid storage area 7 from top to bottom. A condensation pipe 11 through which the coolant continuously passes is rotatably provided in the condensation chamber 1. Regarding its rotation setting method, a stirring part 12 is rotatably provided in the liquid storage area 7. The stirring part 12 is in the shape of a support frame and is fixedly connected to the condensation pipe 11. A rotating block 13 is also fixedly connected to the pipe orifice of the condensation pipe 11. An annular and coaxial first through port 14 and second through port 15 are formed on the rotating block 13, which are respectively communicated with the two pipe orifices of the condensation pipe 11. A first port 16 and a second port 17 are fixedly provided on the condensation chamber 1, which are also designed to be annular and coaxial and are respectively rotatably communicated with the first through port 14 and the second through port 15, so as to cooperate with the rotation setting of the stirring part 12 to realize the rotation setting of the condensation pipe 11 in the condensation area 6. The coolant enters the condensation pipe 11 through the first port 16 and then flows away through the second port 17, circulating in this way;

[0034] Specifically, an air inlet 8 is provided on the chamber wall of the liquid storage area 7, which is communicated with the intake pipeline 3 and is used for the mixed gas to enter the condensation chamber 1. An outlet 10 for the discharged liquid and an air outlet 9 are provided on the chamber wall of the liquid storage area 7, which are respectively used for discharging the condensed chlorosilane and discharging hydrogen. The outlet 10 is communicated with the first output pipeline 4;

[0035] According to the above, the mixed gas is finally cooled in the condensation zone 6, so that the impure chlorosilane is condensed into a liquid state and deposited in the liquid storage zone 7. During the process of the hydrogen gas being discharged from the gas outlet 9, it will form a mixture with the deposited liquid chlorosilane. The stirring part 12 is configured with a rotational driving force, and it can rotate together with the condensation pipe 11 to complete the mixing of the hydrogen gas and the liquid chlorosilane, so as to absorb the hydrogen chloride in the hydrogen gas through the chlorosilane. Therefore, during this process, the separation of the chlorosilane and hydrogen chloride in the mixed gas is synchronously completed. Compared with the prior art, the chlorosilane can be immediately mixed with the hydrogen chloride after being liquefied, thereby increasing the absorption effect of the hydrogen chloride.

[0036] Further, referring to Figure 6 , the vaporization chamber 2 is in communication with the outside, and its internal state is normal pressure. A rotary spray head 18 is rotatably arranged in the vaporization chamber 2. The outside of the vaporization chamber 2 is provided with an inlet 19, which is in communication with the rotary spray head 18. The inlet 19 is in communication with the first output pipeline 4. The present invention further includes a heat exchanger. The intake pipeline 3 and the first output pipeline 4 are arranged to pass through the heat exchanger. When the mixed gas coming out of the reduction furnace and the liquid chlorosilane both pass through the heat exchanger, heat exchange is formed between the two, so as to achieve the effect of pre-cooling the mixed gas before condensation. At this time, the liquid chlorosilane is heated back to the normal temperature state, and it is vaporized, thereby forming a volume expansion and finally forming a pressure release when discharged from the rotary spray head 18, that is, spraying out from the rotary spray head 18 to drive the rotation of the rotation. A transmission cooperation is formed between the rotary spray head 18 and the stirring part 12, so as to complete the supply of the rotational power of the stirring part 12. The rotary spray head 18 and the stirring part 12 can be connected through a pulley assembly to complete the transmission connection.

[0037] It should be understood that during the development process of any actual implementation, such as in any engineering or design project, a large number of specific implementation decisions can be made. Such development efforts may be complex and time-consuming, but for those ordinary technical personnel who benefit from this disclosure, without excessive experimentation, the development efforts will be a routine work of design, manufacturing and production.

[0038] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered within the scope of the claims of the present invention.

Claims

1. A hydrogen circulation system for polysilicon production, characterized in that: It includes a mutually communicating condensation area and a liquid storage area, where: The mixed gas enters the condensation area for condensation and is discharged at the liquid storage area; The condensate is stored in the liquid storage area, and a stirring part for maintaining gas-liquid mixing is provided at the condensation area.

2. The hydrogen circulation system for polysilicon production according to claim 1, characterized in that: A condensate pipe through which a cooling medium passes is movably arranged in the condensation area, and it is connected to the stirring part.

3. The hydrogen circulation system for polysilicon production according to claim 2, characterized in that: The condensation chamber is circular, and the condensate pipe is rotatably arranged in the condensation chamber.

4. The hydrogen circulation system for polysilicon production according to claim 3, characterized in that: The stirring part is rotatably matched with the inner wall of the condensation chamber.

5. The hydrogen circulation system for polysilicon production according to claim 4, characterized in that: It further includes a rotating block, on which a coaxial and annular first through-port and a second through-port are constructed. The first through-port and the second through-port are respectively fixedly communicated with both ends of the condensate pipe. A first port and a second port are fixedly arranged at the condensation area, and they are respectively rotatably communicated with the first through-port and the second through-port.

6. The hydrogen circulation system for polysilicon production according to claim 4, characterized in that: It further includes a first output pipeline and a vaporization chamber. The condensate flows out from the liquid storage area and reaches the vaporization chamber through the first output pipeline. A rotating spray head communicated with the first output pipeline is rotatably arranged in the vaporization chamber, and it is in transmission cooperation with the stirring part. The condensate returns to room temperature in the first output pipeline.

7. The hydrogen circulation system for polysilicon production according to claim 6, characterized in that:

8. The hydrogen circulation system for polysilicon production according to claim 7, characterized in that: The condensate forms a heat exchange with the mixed gas during the process of passing through the first output pipeline. It further includes a heat exchanger and an intake pipeline. The mixed gas reaches the condensation area through the intake pipeline, and both the intake pipeline and the first output pipeline pass through the heat exchanger.

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