Electric heater for convection chlorosilane and heating method thereof

Abstract

The application discloses a novel convection type electric heater for chlorosilane and a heating method thereof, which comprises an outer shell body, material inlets and outlets are arranged at two ends of the outer shell body respectively, the material inlets and outlets are connected to a chlorosilane material pipeline through first flanges, so that the outer shell body becomes a part of the chlorosilane material pipeline; an inner container cylinder is arranged in the outer shell body, a flow guide cylinder is arranged in the inner container cylinder, a flow guide space is formed between the inner container cylinder and the flow guide cylinder, and an electric heating element is arranged in the flow guide space through an insulating piece; in the application, the material inlets and outlets are connected to the chlorosilane material pipeline through the first flanges, so that the outer shell body becomes a part of the chlorosilane material pipeline; in the case of limited space, the chlorosilane material pipeline can be directly connected, a large range of modification of chlorosilane material pipeline arrangement is not needed, installation space is reduced, and the electric heater is installed through the first flanges, so that the electric heater is convenient to disassemble during maintenance.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of heater, and particularly relates to a novel convection type electric heater for chlorosilane and a heating method thereof. BACKGROUND

[0002] The improved Siemens method is a mainstream method for producing polysilicon, in which hydrogen chloride is synthesized by using chlorine and hydrogen, the hydrogen chloride and industrial silicon powder are synthesized into trichlorosilane at a certain temperature, the trichlorosilane is separated and purified by rectification, and the purified trichlorosilane is subjected to CVD reaction in a hydrogen reduction furnace to produce high-purity polysilicon.

[0003] The traditional heating method for trichlorosilane is to use a radiation type electric heater, in which the trichlorosilane enters a coil in a container through a pipeline, a plurality of radiation type electric heating cores are installed in the container, the medium is indirectly heated in the coil, and the outlet reaches the required process temperature. The early equipment investment cost is high, and the container of the traditional radiation type electric heater occupies a large area, which is very inconvenient for the working conditions with site requirements. Therefore, a novel convection type electric heater for chlorosilane and a heating method thereof are provided. SUMMARY

[0004] The present application aims to provide a novel convection type electric heater for chlorosilane and a heating method thereof to solve the problems in the background.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical scheme: a novel convection type electric heater for chlorosilane, comprising an outer shell, a material inlet and a material outlet are arranged at two ends of the outer shell respectively, the material inlet and the material outlet are connected on a chlorosilane material pipeline through a first flange, so that the outer shell becomes a part of the chlorosilane material pipeline;

[0006] An inner container is arranged in the outer shell, a flow guide cylinder is arranged in the inner container, a flow guide space for the flow of chlorosilane material is formed between the inner container and the flow guide cylinder, an electric heating element is arranged in the flow guide space through an insulating piece, and the electric heating element is used for heating treatment of the chlorosilane material.

[0007] Preferably, a stable assembly is arranged on the outer shell at equal intervals, the stable assembly is used for tightening and fixing the inner container, and the insulating piece and the electric heating element are fixed between the inner container and the flow guide cylinder.

[0008] Preferably, the stable assembly comprises an outer guide column and an inner fixing pin, a pin hole is formed in the outer guide column, the pin hole is communicated with the inside of the outer shell, the inner fixing pin is inserted into the pin hole and abuts against the inner container, and the inner container abuts and fixes the insulating piece and the electric heating element on the outer circumferential side of the flow guide cylinder.

[0009] The outer guide column and the inner fixing pin are both provided with a second flange, the two second flanges are fixedly connected through bolts, and the connection between the two second flanges is sealed.

[0010] Preferably, the outer shell is provided with equiangularly distributed electrode assemblies on the outer circumferential side, the electrode assemblies are connected with the electric heating element, and the electrode assemblies are used to supply power to the electric heating element.

[0011] Preferably, the electrode assemblies comprise outer insulating columns and electrode pieces, the outer insulating columns are provided with electrode insertion holes, and the electrode pieces are inserted into the electrode insertion holes and connected with the electric heating element.

[0012] The outer insulating column and the electrode piece are both provided with a third flange, the two third flanges are fixedly connected through bolts, and an insulating sleeve is arranged between the connection between the two third flanges and the electrode piece.

[0013] Preferably, the flow guide cylinder is of an elliptical structure at one end facing the material inlet, and the overall flow guide cylinder is of a streamlined structure.

[0014] Preferably, the insulating piece is a I-shaped long insulating piece, the insulating piece is arranged between the container inner cylinder and the flow guide cylinder along the axial direction of the flow guide cylinder, and the insulating piece is an insulating piece made of ceramic material.

[0015] Preferably, the electric heating element is of a meshed cylinder structure, the electric heating element is provided with a plurality of circularly arrayed sockets, and the insulating piece is clamped on the sockets of the electric heating element, so that the electric heating element is suspended between the container inner cylinder and the flow guide cylinder.

[0016] Preferably, the outer shell is of a straight-through cylinder structure.

[0017] A heating method of a new type of convection type electric heater for chlorosilane, comprising the following steps:

[0018] A: When the chlorosilane material is heated, the electrode assemblies are used to supply power to the electric heating element, at this time, the meshed cylinder structure starts to heat, and the chlorosilane material medium enters the outer shell through the chlorosilane material pipeline and the material inlet;

[0019] B: At this time, the chlorosilane material meets the flow guide cylinder, the elliptical structure at one end of the flow guide cylinder forcibly divides the chlorosilane material, so that the chlorosilane material enters the flow guide space between the container inner cylinder and the flow guide cylinder, the electric heating element located in the flow guide space heats the chlorosilane material, and the electric heating element in the meshed cylinder structure forcibly causes the convection of the chlorosilane material in the flow guide space, so that the chlorosilane material quickly takes away the surface temperature of the electric heating element, and the electric heating element uniformly heats the chlorosilane material.

[0020] C: The chlorosilane material after flowing through the electric heating element is discharged through the material outlet, and the heating of the chlorosilane material is completed.

[0021] Compared with the prior art, the present application has the following advantages:

[0022] 1. The material inlet and the material outlet in the present application are connected to the chlorosilane material pipeline through the first flange, so that the shell body becomes part of the chlorosilane material pipeline. In the case of limited space, the chlorosilane material pipeline can be directly connected without the need for large-scale modification of the chlorosilane material pipeline layout, thereby reducing the installation space. The electric heater is installed through the first flange, which is convenient to disassemble during maintenance. Only the first flange needs to be removed, and the entire electric heater can be removed, thereby facilitating maintenance and repair.

[0023] 2. The electric heater in the present application adopts a straight-through cylinder structure, and the whole is a flow guide cylinder with an elliptical structure, which is a streamlined structure. The pressure difference of the chlorosilane material at the material inlet and the material outlet in the shell body is small. As shown in the figure, it is a pressure distribution simulation diagram of the chlorosilane material in the shell body. The pressure of the chlorosilane material at the material inlet in the shell body is the largest, and then uniformly decreases in the process of flowing to the material outlet, thereby ensuring the requirement of the electric heater for the pressure difference.

[0024] 3. The present application is provided with a flow guide cylinder with an elliptical structure, and the whole is a streamlined structure. The electric heating element has a net-like cylinder structure, so that the chlorosilane material passes through the electric heating element with a net-like cylinder structure to form forced convection between the inner cylinder of the container and the flow guide cylinder, so that the chlorosilane material quickly takes away the surface temperature of the electric heating element, and the electric heating element uniformly heats the chlorosilane material. Compared with the traditional radiant electric heater, the heat exchange efficiency is improved, and the heating efficiency of the electric heater is improved.

[0025] 4. The present application is provided with an outer guide column, an inner fixing pin, a pin hole, a second flange and an insulating piece. During assembly of the electric heater, the insulating piece is first fitted into the bayonet on the electric heating element, and then the insulating piece and the electric heating element are installed between the inner cylinder of the container and the flow guide cylinder. Then the inner fixing pin is inserted into the pin hole and abuts against the inner cylinder of the container, so that the inner cylinder of the container abuts and fixes the insulating piece and the electric heating element on the outer peripheral side of the flow guide cylinder. Then the two second flanges are fixed and connected by using bolts, so as to ensure the installation stability of the insulating piece and the electric heating element between the inner cylinder of the container and the flow guide cylinder, and ensure that the electric heater can operate stably. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 It is a schematic diagram of the overall cross-sectional structure of the present application.

[0027] Figure 2 It is a schematic diagram of the cross-sectional structure of the present application.

[0028] Figure 3 Cross-sectional structure schematic diagram of the stable assembly of the present application;

[0029] Figure 4 Cross-sectional structure schematic diagram of the electrode assembly of the present application;

[0030] Figure 5 Pressure distribution simulation diagram of the chlorosilane material in the outer shell 1 of the present application;

[0031] Figure 6 Flow direction diagram of the chlorosilane material in the outer shell 1 of the present application;

[0032] Figure 7 Flow direction simulation diagram of the chlorosilane material between the flow guide cylinder 6 and the electric heating element 8 of the present application;

[0033] Figure 8 Temperature distribution simulation diagram of the chlorosilane material in the outer shell 1 of the present application.

[0034] In the figure: 1, outer shell; 2, material inlet; 3, material outlet; 4, first flange; 5, container inner cylinder; 6, flow guide cylinder; 7, insulating piece; 8, electric heating element; 801, bayonet; 9, stable assembly; 901, outer guide column; 902, inner fixing pin; 903, pin hole; 904, second flange; 10, electrode assembly; 1001, outer insulating column; 1002, electrode piece; 1003, electrode socket; 1004, third flange; 1005, insulating sleeve. DETAILED DESCRIPTION

[0035] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0036] Please refer to Figures 1-4 The novel convection type electric heater for chlorosilane provided by the present application comprises an outer shell 1, the outer shell 1 is a straight-through type cylinder structure, the outer shell 1 is provided with a material inlet 2 and a material outlet 3 at two ends respectively, the material inlet 2 and the material outlet 3 are connected on a chlorosilane material pipeline through a first flange 4, so that the outer shell 1 becomes a part of the chlorosilane material pipeline;

[0037] The material inlet 2 and the material outlet 3 are connected on the chlorosilane material pipeline through the first flange 4, so that the shell 1 becomes a part of the chlorosilane material pipeline, in the case of limited site, the chlorosilane material pipeline can be directly connected, without the need of large-scale modification of the chlorosilane material pipeline arrangement, the installation space is reduced, and the electric heater is installed through the first flange 4, which is convenient to disassemble during maintenance, and the whole electric heater can be disassembled by only removing the first flange 4, so that the maintenance and repair are facilitated.

[0038] The electric heater in the application adopts a straight-through type cylinder structure, and the whole is a flow guide cylinder 6 with an elliptical structure at one end, so that the pressure difference of the chlorosilane material at the material inlet 2 and the material outlet 3 in the shell 1 is small, as shown in Figure 5 It is a pressure distribution simulation diagram of the chlorosilane material in the shell 1, the pressure of the chlorosilane material at the material inlet 2 in the shell 1 is the largest, and then uniformly decreases in the process of flowing to the material outlet 3, so as to ensure the requirement of the electric heater on the pressure difference.

[0039] The inside of the shell 1 is provided with a container inner cylinder 5, the inside of the container inner cylinder 5 is provided with a flow guide cylinder 6, one end of the flow guide cylinder 6 towards the material inlet 2 is an elliptical structure, and the whole of the flow guide cylinder 6 is a streamlined structure, the container inner cylinder 5 and the flow guide cylinder 6 form a flow guide space for the flow of the chlorosilane material, as shown in Figure 6 It is a flow direction diagram of the chlorosilane material in the shell 1, as shown in Figure 7 It is a chlorosilane material flow direction simulation diagram between the flow guide cylinder 6 and the electric heating element 8, the flow guide space is provided with the electric heating element 8 through the insulating piece 7, the insulating piece 7 is a I-shaped long strip insulating piece, the insulating piece 7 is arranged between the container inner cylinder 5 and the flow guide cylinder 6 along the axial direction of the flow guide cylinder 6, and the insulating piece 7 is an insulating piece prepared from ceramic material, the electric heating element 8 is a net-shaped cylinder structure, the net-shaped cylinder structure of the electric heating element 8 forces the convection of the chlorosilane material in the flow guide space, so that the chlorosilane material quickly takes away the surface temperature of the electric heating element 8, so that the surface temperature of the electric heating element 8 is not easy to be too high, and the electric heating element 8 uniformly heats the chlorosilane material, as shown in Figure 8 It is a temperature distribution simulation diagram of the chlorosilane material in the shell 1, as shown in Figure 8It can be known that the chlorosilane material is gradually heated in the outer shell 1 by the electric heating element 8, the temperature gradually rises, when reaching the material outlet 3, the chlorosilane material is heated to the required process temperature, the electric heating element 8 is provided with a bayonet 801 in a circular array, the insulating part 7 is clamped on the bayonet 801 of the electric heating element 8, so that the electric heating element 8 is suspended between the container inner cylinder 5 and the flow guide cylinder 6, the electric heating element 8 is used for heating treatment of the chlorosilane material, the outer periphery of the outer shell 1 is provided with an electrode assembly 10 distributed at equal angles, the electrode assembly 10 is connected with the electric heating element 8, and the electrode assembly 10 is used for power supply to the electric heating element 8, the electrode assembly 10 comprises an outer insulating column 1001 and an electrode part 1002, the outer insulating column 1001 is provided with an electrode insertion hole 1003, the electrode part 1002 is inserted into the electrode insertion hole 1003 and connected with the electric heating element 8; the outer insulating column 1001 and the electrode part 1002 are both provided with a third flange 1004, the two third flanges 1004 are fixedly connected through bolts, and an insulating sleeve 1005 is arranged between the connection positions of the two third flanges 1004 and the electrode part 1002;

[0040] The present application is provided with a flow guide cylinder 6 with an elliptical structure at one end and a streamlined structure as a whole, and an electric heating element 8 in a net-like cylinder structure, so that the chlorosilane material is forced to convect between the container inner cylinder 5 and the flow guide cylinder 6 through the electric heating element 8 in a net-like cylinder structure, the surface temperature of the electric heating element 8 is quickly taken away by the chlorosilane material, the electric heating element 8 uniformly heats the chlorosilane material, and the heat exchange efficiency is improved compared with the traditional radiant electric heater, and the heating efficiency of the electric heater is further improved.

[0041] In the embodiment, as shown in the figure, Figures 1-4 The outer shell 1 is provided with a stable assembly 9 distributed at equal intervals, the stable assembly 9 is used for tightening and fixing the container inner cylinder 5, the insulating part 7 and the electric heating element 8 are fixed between the container inner cylinder 5 and the flow guide cylinder 6, the stable assembly 9 comprises an outer guide column 901 and an inner fixing pin 902, the outer guide column 901 is provided with a pin hole 903, the pin hole 903 is communicated with the inside of the outer shell 1, the inner fixing pin 902 is inserted into the pin hole 903 and abuts against the container inner cylinder 5, so that the container inner cylinder 5 abuts and fixes the insulating part 7 and the electric heating element 8 on the outer periphery of the flow guide cylinder 6; the outer guide column 901 and the inner fixing pin 902 are both provided with a second flange 904, the two second flanges 904 are fixedly connected through bolts, and the connection position between the two second flanges 904 is sealed;

[0042] The application is provided with an outer guide column 901, an inner fixing pin 902, a pin hole 903, a second flange 904 and an insulating piece 7, when assembling the electric heater, first, the insulating piece 7 is clamped into the bayonet 801 on the electric heating element 8, then the insulating piece 7 and the electric heating element 8 are installed between the container inner cylinder 5 and the flow guide cylinder 6, then the inner fixing pin 902 is inserted into the pin hole 903 and abuts against the container inner cylinder 5, so that the container inner cylinder 5 abuts and fixes the insulating piece 7 and the electric heating element 8 on the outer circumferential side of the flow guide cylinder 6, then the two second flanges 904 are fixed and connected by using bolts, so as to ensure the installation stability of the insulating piece 7 and the electric heating element 8 between the container inner cylinder 5 and the flow guide cylinder 6, and ensure that the electric heater can stably operate.

[0043] The application provides a heating method of a novel convection type electric heater for chlorosilane, which comprises the following steps:

[0044] A: when the chlorosilane material is heated, the electrode assembly 10 is used for supplying power to the electric heating element 8, at this time, the mesh cylinder structure starts to heat, and the chlorosilane material medium enters the shell body 1 through the chlorosilane material pipeline and the material inlet 2;

[0045] B: at this time, the chlorosilane material meets the flow guide cylinder 6, the elliptical structure at one end of the flow guide cylinder 6 can force the chlorosilane material to be divided, so that the chlorosilane material enters the flow guide space between the container inner cylinder 5 and the flow guide cylinder 6, the electric heating element 8 located in the flow guide space can heat the chlorosilane material, and the electric heating element 8 in the mesh cylinder structure can force the chlorosilane material to flow in the flow guide space, so that the chlorosilane material quickly takes away the surface temperature of the electric heating element 8, and the electric heating element 8 uniformly heats the chlorosilane material;

[0046] C: then, the chlorosilane material flowing through the electric heating element 8 is discharged through the material outlet 3, and the heating of the chlorosilane material is completed.

[0047] Although the embodiments of the application have been shown and described, it can be understood by those skilled in the art that various changes, modifications, replacements and variations can be made to the embodiments without departing from the principles and spirits of the application, and the scope of the application is defined by the appended claims and their equivalents.

Claims

1. A convection-type electric heater for chlorosilanes, characterized in that, Includes an outer shell (1), with a material inlet (2) and a material outlet (3) respectively provided at both ends of the outer shell (1). The material inlet (2) and the material outlet (3) are connected to the chlorosilane material pipeline through a first flange (4), so that the outer shell (1) becomes part of the chlorosilane material pipeline. The outer shell (1) is provided with a container inner cylinder (5), and the container inner cylinder (5) is provided with a flow guide cylinder (6). A flow guide space for the flow of chlorosilane material is formed between the container inner cylinder (5) and the flow guide cylinder (6). An electric heating element (8) is provided in the flow guide space through an insulating component (7). The electric heating element (8) is used to heat the chlorosilane material. The outer shell (1) is provided with stabilizing components (9) distributed at equal intervals. The stabilizing components (9) are used to tighten and fix the inner cylinder (5) of the container, so that the insulating component (7) and the heating element (8) are fixed between the inner cylinder (5) of the container and the guide cylinder (6). The stabilizing component (9) includes an outer guide post (901) and an inner fixing pin (902). The outer guide post (901) has a pin hole (903) which communicates with the interior of the outer shell (1). The inner fixing pin (902) is inserted into the pin hole (903) and abuts against the inner cylinder (5) of the container, so that the inner cylinder (5) of the container abuts and fixes the insulating component (7) and the heating element (8) on the outer periphery of the guide tube (6). The outer guide post (901) and the inner fixing pin (902) are both provided with a second flange (904), the two second flanges (904) are fixedly connected by bolts, and the connection between the two second flanges (904) is sealed; The guide tube (6) has an elliptical structure at the end facing the material inlet (2), and the guide tube (6) as a whole has a streamlined structure; The insulating component (7) is an I-shaped long strip insulating component. The insulating component (7) is arranged between the inner cylinder (5) of the container and the guide cylinder (6) along the axial direction of the guide cylinder (6). The insulating component (7) is an insulating component made of ceramic material. The heating element (8) has a mesh cylindrical structure. The heating element (8) has a bayonet (801) arranged in a circular array. The insulating part (7) is snapped into the bayonet (801) on the heating element (8), so that the heating element (8) is suspended between the inner cylinder (5) of the container and the guide cylinder (6).

2. The electric heater for convection chlorosilane according to claim 1, characterized in that: The outer periphery of the outer shell (1) is provided with electrode assemblies (10) distributed at equal angles. The electrode assemblies (10) are connected to the heating element (8) and are used to supply power to the heating element (8).

3. The electric heater for convection chlorosilane according to claim 2, characterized in that: The electrode assembly (10) includes an outer insulating post (1001) and an electrode element (1002). The outer insulating post (1001) is provided with an electrode socket (1003). The electrode element (1002) is inserted into the electrode socket (1003) and connected to the heating element (8). Both the outer insulating column (1001) and the electrode (1002) are provided with a third flange (1004), and the two third flanges (1004) are fixedly connected by bolts. An insulating sleeve (1005) is provided between the connection between the two third flanges (1004) and the electrode (1002).

4. The electric heater for convection chlorosilane according to claim 1, characterized in that: The outer shell (1) is a straight cylindrical structure.

5. A heating method for a convection-type electric heater for chlorosilanes according to any one of claims 1-4, characterized in that, Includes the following steps: A: When the chlorosilane material is heated, the electrode assembly (10) is used to supply power to the heating element (8). At this time, the mesh cylinder structure begins to heat up, and the chlorosilane material medium enters the outer shell (1) through the chlorosilane material pipeline and the material inlet (2). B: At this time, the chlorosilane material will encounter the guide tube (6). The elliptical structure at one end of the guide tube (6) will force the chlorosilane material to be diverted, so that the chlorosilane material enters the guide space between the inner cylinder (5) of the container and the guide tube (6). The electric heating element (8) located in the guide space will heat the chlorosilane material. At the same time, the electric heating element (8) with the mesh cylinder structure will force the chlorosilane material to convect in the guide space, so that the chlorosilane material will quickly carry away the surface temperature of the electric heating element (8), so that the electric heating element (8) will uniformly heat the chlorosilane material. C: Then the chlorosilane material flowing through the heating element (8) is discharged through the material outlet (3), and the heating of the chlorosilane material is completed.

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