Polycrystalline silicon reduction furnace

Abstract

The utility model provides a polycrystalline silicon reduction furnace, and belongs to the technical field of polycrystalline silicon production and manufacturing. The polycrystalline reduction furnace comprises a furnace body, the outer ring pipe is arranged around the top of the furnace body, a plurality of feeding machine bases extending into the furnace body are arranged on the outer ring pipe at intervals, and each feeding machine base is provided with a top feeding nozzle communicated with the outer ring pipe; materials sprayed out of the top feeding nozzles can collide with one another and are evenly sprayed to the tops of the silicon rods. The bottom feeding nozzle is arranged at the bottom of the furnace body; and the mixer is used for containing a mixture for forming polycrystalline silicon, and a discharging port of the mixer is connected with the outer ring pipe through a top feeding pipe and connected with a bottom feeding nozzle through a bottom feeding pipe. The polycrystalline silicon reduction furnace can greatly reduce the formation of cauliflower materials at the top of the silicon rod, improve the product quality and reduce the generation of abnormal heat.

Description

Technical Field

[0001] The utility model belongs to the technical field of polysilicon production and manufacturing, and particularly relates to a polysilicon reduction furnace. Background Art

[0002] During the current polysilicon production process, in order to pursue high output and low power consumption, a large amount of material is generally used for production. Due to the spraying height of the bottom feeding nozzle, uneven gas field and temperature field in the reduction furnace, cauliflower material appears at the top in the middle and late stages of silicon rod growth, seriously affecting the product quality. In the current market environment with such strict quality requirements, reducing the output of cauliflower material is an urgent task. Summary of the Utility Model

[0003] In view of the above problems existing in the prior art, the purpose of the embodiment of the present utility model is to provide a polysilicon reduction furnace. This polysilicon reduction furnace can greatly reduce the formation of cauliflower material at the top of the silicon rod, improve the product quality and reduce the generation of abnormal furnace batches.

[0004] The technical solution adopted in the embodiment of the present utility model is as follows:

[0005] A polysilicon reduction furnace, comprising:

[0006] A furnace body;

[0007] An outer ring pipe is arranged around the top of the furnace body. A plurality of feeding machine seats are spaced on the outer ring pipe and respectively extend into the interior of the furnace body. Each feeding machine seat is respectively provided with a top feeding nozzle communicated with the outer ring pipe. The materials ejected by the plurality of top feeding nozzles can collide with each other and be evenly sprinkled on the top of the silicon rod;

[0008] A bottom feeding nozzle is arranged at the bottom of the furnace body;

[0009] A mixer is used for containing the mixture for forming polysilicon. The discharge port of the mixer is connected with the outer ring pipe through a top feeding pipe and is connected with the bottom feeding nozzle through a bottom feeding pipe.

[0010] Further, the top feeding nozzle and the feeding machine seat are detachably connected.

[0011] Further, the top feeding nozzle and the feeding machine seat are connected by threads.

[0012] Further, the polysilicon reduction furnace further includes a hydrogen feeding pipeline and a nitrogen feeding pipeline. The hydrogen feeding pipeline and the nitrogen feeding pipeline are respectively connected with the top feeding pipe through an intermediate pipeline, and a first manual valve is arranged on the intermediate pipeline.

[0013] Further, a second manual valve, a regulating valve, a flowmeter, and a third manual valve are successively arranged on the top feed pipe along the direction of material flow.

[0014] Further, a fourth manual valve and a fifth manual valve are successively arranged on the downstream area of the third manual valve on the top feed pipe, and the fifth manual valve is close to the connection part of the top feed pipe and the outer ring pipe.

[0015] Further, a plurality of the top feed nozzles are respectively oriented obliquely upward of the furnace body, and the axes of a plurality of the top feed nozzles have the same included angle with the axis of the furnace body.

[0016] Further, the number of the top feed nozzles is four.

[0017] Further, a recycled hydrogen feed pipe and a trichlorosilane pipe are connected to the mixer.

[0018] Further, the bottom feed nozzles are distributed in a concentric circular ring on the bottom of the furnace body.

[0019] Compared with the prior art, the beneficial effects of the embodiments of the present utility model are as follows:

[0020] In the furnace body of the polysilicon reduction furnace of the present utility model, a plurality of top feed nozzles are arranged at the top. The materials ejected from the plurality of top feed nozzles can collide with each other and be evenly sprinkled on the top of the silicon rod, so that the formation of cauliflower materials at the top of the silicon rod can be greatly reduced, the temperature at the top of the silicon rod can be reduced, the probability of melting of the silicon rod cross beam can be reduced, the product quality can be improved, and the generation of abnormal furnace batches can be reduced.

[0021] It should be understood that the foregoing general description and the following detailed description are only exemplary and explanatory, and are not used to limit the present utility model.

[0022] The overview of various implementations or examples of the technologies described in the present utility model is not a full disclosure of the entire scope of the disclosed technologies or all features. Description of the Drawings

[0023] In the drawings that are not necessarily drawn to scale, the same reference numerals may describe similar components in different views. The drawings generally illustrate various embodiments by way of example rather than limitation, and are used together with the description of the specification and the claims to explain the embodiments of the present utility model. When appropriate, the same reference numerals are used to refer to the same or similar parts in all the drawings.

[0024] Figure 1 It is a schematic structural diagram of the polysilicon reduction furnace of the embodiment of the present utility model;

[0025] Figure 2This is a schematic structural diagram of the connection of the top feed nozzle on the outer ring pipe of the embodiment of the present utility model.

[0026] In the figure: 1, furnace body; 2, outer ring pipe; 3, feed machine base; 4, top feed nozzle; 5, mixer; 6, top feed pipe; 7, bottom feed pipe; 8, trichlorosilane pipe; 9, recycled hydrogen feed pipe; 10, nitrogen supply pipeline; 11, hydrogen supply pipeline; 12, intermediate pipeline; 13, first manual valve; 14, regulating valve; 15, flowmeter; 16, second manual valve; 17, third manual valve; 18, fourth manual valve; 19, check valve; 20, bottom feed nozzle. Specific embodiments

[0027] In order to make the objectives, technical solutions and advantages of the embodiments of the present utility model clearer, the technical solutions of the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are some but not all of the embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the described embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0028] Unless otherwise defined, the technical terms or scientific terms used in the present utility model shall have the ordinary meanings understood by those of ordinary skill in the art to which the present utility model belongs. The "first", "second" and similar terms used in the present utility model do not denote any order, quantity or importance, but are only used to distinguish different components. The terms such as "including" or "comprising" mean that the elements or objects appearing before this word cover the elements or objects listed after this word and their equivalents, without excluding other elements or objects. The terms such as "connected" or "coupled" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The terms such as "upper", "lower", "left" and "right" are only used to represent relative positional relationships, and when the absolute position of the object being described changes, the relative positional relationship may also change accordingly. In order to keep the following description of the embodiments of the present utility model clear and concise, the detailed descriptions of known functions and known components are omitted in the present utility model.

[0029] As Figure 1 shown, the embodiment of the present utility model provides a polysilicon reduction furnace, which includes a furnace body 1, an outer ring pipe 2, a bottom feed nozzle 20 and a mixer 5.

[0030] The mixture used for the reaction to generate polysilicon is introduced into the furnace body 1, and polysilicon is formed under a high-temperature and high-pressure environment. The formed polysilicon will be deposited on the silicon core in the furnace body 1. As the chemical reaction continues, more and more polysilicon is deposited on the silicon core, gradually covering the entire silicon core and becoming a rod-shaped body wrapped with polysilicon on the outside, commonly known as a silicon rod.

[0031] The outer ring pipe 2 is arranged around the top of the furnace body 1. A plurality of feeding machine seats 3 are arranged on the outer ring pipe 2 at intervals, and each feeding machine seat 3 extends into the interior of the furnace body 1. The plurality of feeding machine seats 3 are evenly arranged around the furnace body 1.

[0032] Each feeding machine seat 3 is respectively provided with a top feeding nozzle 4 communicating with the outer ring pipe 2. The materials sprayed by the plurality of top feeding nozzles 4 can collide with each other to form a turbulent flow and be evenly sprinkled on the top of the silicon rod, thereby reducing the formation of cauliflower material at the top of the silicon rod.

[0033] The bottom feeding nozzle 20 is arranged at the bottom of the furnace body 1. The number of the bottom feeding nozzles 20 is also multiple. The mixture used for forming polysilicon can be sprayed onto the top inside the reduction furnace and sprinkled on the silicon core through the bottom feeding nozzle 20.

[0034] The mixer 5 is used to hold the mixture for forming polysilicon. Among them, the mixture includes recycled hydrogen material and trichlorosilane material.

[0035] The discharge port of the mixer 5 is connected to the outer ring pipe 2 through the top feeding pipe 6 and to the bottom feeding nozzle 20 through the bottom feeding pipe 7.

[0036] In the top of the furnace body 1 of the polysilicon reduction furnace in this embodiment, a plurality of top feeding nozzles 4 are provided. The materials sprayed by the plurality of top feeding nozzles 4 can collide with each other and be evenly sprinkled on the top of the silicon rod. In this way, the formation of cauliflower material at the top of the silicon rod can be greatly reduced, the temperature at the top of the silicon rod can be reduced, the probability of the silicon rod crossbeam melting can be reduced, the product quality can be improved, and the generation of abnormal furnace batches can be reduced.

[0037] Moreover, the reaction deposition of the materials at the top of the silicon rod is increased, the overall deposition rate is improved, the proportion of unreacted materials escaping from the tail gas holes is reduced, and thus the primary reduction conversion rate is improved.

[0038] The mixture stored in the mixer 5 in this embodiment for the reaction to generate polysilicon mainly includes recycled hydrogen and trichlorosilane. Preferably, the mixer 5 is connected with a recycled hydrogen material pipe 9 and a trichlorosilane pipe 8. Recycled hydrogen can be transported into the mixer 5 through the recycled hydrogen material pipe 9, and trichlorosilane can be transported into the mixer 5 through the trichlorosilane pipe 8.

[0039] Such as Figure 1 And Figure 2As shown, in some embodiments, a plurality of top feed nozzles 4 located inside the furnace body 1 are respectively oriented obliquely upward of the furnace body 1, and the angles between the axes of the plurality of top feed nozzles 4 and the axis of the furnace body 1 are the same.

[0040] Alternatively, the angles between the axes of the plurality of top feed nozzles 4 and the horizontal line perpendicular to the axis of the furnace body 1 are the same, and preferably 30°. That is, each top feed nozzle 4 is connected to the inside of the furnace body 1 with a 30° upward inclination.

[0041] The materials ejected by the plurality of top feed nozzles 4 respectively will collide above the center of the furnace body 1.

[0042] Preferably, the number of top feed nozzles 4 located above the inside of the furnace body 1 is four. The angle between the four top feed nozzles 4 is 90°.

[0043] In some embodiments, the bottom feed nozzles 20 at the bottom inside the furnace body 1 are distributed in a concentric circular ring.

[0044] In some embodiments, the top feed nozzle 4 and the feed base 3 are detachably connected, so as to realize the disassembly and replacement of the top feed nozzle 4.

[0045] Specifically, the top feed nozzle 4 and the feed base 3 can be connected by threads. For example, the feed base 3 is provided with a threaded connection hole communicating with the outer ring pipe 2, and the top feed nozzle 4 is provided with a stud connected to the threaded connection hole.

[0046] In some embodiments, a first manual valve 13, a regulating valve 14, a flow meter 15 and a second manual valve 16 are sequentially arranged on the top feed pipe 6 along the direction of material flow. Preferably, a regulating valve 14 is also provided on the bottom feed pipe 7.

[0047] The flow meter 15 is used to monitor the feed amount of the mixed material entering the furnace body 1. The regulating valve 14 can be used to control the feed amount of the mixed material entering the top inside the furnace body 1 to ensure uniform distribution of materials in the upper and lower parts of the silicon rod, so as to reduce the formation of cauliflower material at the top of the silicon rod. The first manual valve 13 and the second manual valve 16 are respectively used to control the on-off of the top feed pipe 6.

[0048] This embodiment can flexibly adjust the top feed flow rate of the reduction furnace. According to daily production experience, cauliflower material begins to be generated at the top of the silicon rod when the reduction furnace grows between 20h and 25h. To suppress the generation of cauliflower material, the top feed participates in the reaction growth of the reduction furnace throughout the process, and the top feed flow rate is adjusted according to the growth situation and atomization situation of the silicon rod inside the furnace until the furnace is stopped after the silicon rod reaches the target requirements.

[0049] In some embodiments, a third manual valve 17 and a fourth manual valve 18 are sequentially provided on the top feed pipe 6 in the downstream area of the second manual valve 16, and the fourth manual valve 18 is close to the connection of the top feed pipe 6 and the outer ring pipe 2. The third manual valve 17 and the fourth manual valve 18 can be respectively used to control the disconnection and separation of the top feed pipe 6 line.

[0050] Specifically, when it is necessary to separate the furnace body 1 from the mixer 5, the flange under the third manual valve 17 can be disassembled to disconnect the top feed pipe 6.

[0051] In some embodiments, the polysilicon reduction furnace further includes a hydrogen supply pipeline 11 and a nitrogen supply pipeline 10.

[0052] The hydrogen supply pipeline 11 and the nitrogen supply pipeline 10 are respectively connected to the top feed pipe 6 through an intermediate pipeline 12, and a check valve 19 is provided on the intermediate pipeline 12.

[0053] The connection of the intermediate pipeline 12 and the top feed pipe 6 is located in the area between the regulating valve 14 and the flowmeter 15. The hydrogen supply pipeline 11 and the nitrogen supply pipeline 10 are provided to replace the top feed pipe 6 line during furnace startup to ensure the cleanliness and purity of the pipeline. The check valve 19 is provided on the intermediate pipeline 12 to prevent material backflow.

[0054] In addition, after the reduction furnace is shut down, the flange under the 12 third manual valve 17 needs to be disassembled. During the cleaning of the reduction furnace, the top feed pipe 6 can be purged with nitrogen through the nitrogen supply pipeline 10, which can effectively prevent water from entering the top feed pipe 6 and avoid blockage of the top feed pipe 6 by the hydrolysis products resulting from the reaction of water with the residual material.

[0055] The above description is intended to be illustrative rather than restrictive, and those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present disclosure. Moreover, the above examples (or one or more of their solutions) can be used in combination with each other, and considering these embodiments, they can be combined with each other in various combinations or permutations.

Claims

1. A polysilicon reduction furnace, characterized in that, Comprising: Furnace body; Outer ring pipe, arranged around the top of the furnace body, a plurality of feeding machine seats are spaced on the outer ring pipe and respectively extend into the interior of the furnace body, and each feeding machine seat is respectively provided with a top feeding nozzle communicated with the outer ring pipe. Materials ejected from the plurality of top feeding nozzles can collide with each other and be evenly sprinkled on the top of the silicon rod; Bottom feeding nozzle, arranged at the bottom of the furnace body; Mixer, used for containing the mixture for forming polysilicon. The discharge port of the mixer is connected to the outer ring pipe through a top feeding pipe and to the bottom feeding nozzle through a bottom feeding pipe.

2. A polysilicon reduction furnace according to claim 1, characterized in that, The top feeding nozzle and the feeding machine seat are detachably connected.

3. The polysilicon reduction furnace according to claim 2, characterized in that, The top feeding nozzle and the feeding machine seat are connected by threads.

4. A polysilicon reduction furnace according to claim 1, characterized in that, A first manual valve, a regulating valve, a flowmeter and a second manual valve are sequentially arranged on the top feeding pipe along the material flow direction.

5. The polysilicon reduction furnace according to claim 4, characterized in that, The polysilicon reduction furnace further includes a hydrogen feeding pipeline and a nitrogen feeding pipeline. The hydrogen feeding pipeline and the nitrogen feeding pipeline are respectively connected to the top feeding pipe through an intermediate pipeline, and a check valve is arranged on the intermediate pipeline.

6. The polysilicon reduction furnace according to claim 4, wherein, A third manual valve and a fourth manual valve are further sequentially arranged on the top feeding pipe in the downstream area of the second manual valve, and the fourth manual valve is close to the connection of the top feeding pipe and the outer ring pipe.

7. A polysilicon reduction furnace according to claim 1, characterized in that, The plurality of top feeding nozzles are respectively oriented obliquely upward of the furnace body, and the axes of the plurality of top feeding nozzles have the same included angle with the axis of the furnace body.

8. The polysilicon reduction furnace according to claim 7, wherein, The number of the top feeding nozzles is four.

9. A polysilicon reduction furnace according to claim 1, characterized in that, A recycled hydrogen material pipe and a trichlorosilane pipe are connected to the mixer.

10. A polysilicon reduction furnace as claimed in claim 1, characterized in that, The bottom feeding nozzles are distributed in a concentric circular ring at the bottom of the furnace body.

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