Trichlorosilane low-temperature vaporization system

Abstract

The utility model provides a trichlorosilane low-temperature vaporization system, and relates to the technical field of polycrystalline silicon production. The trichlorosilane low-temperature vaporization system comprises a hydrogen conveying pipe, a trichlorosilane conveying pipe, a gas-liquid mixer, a superheater and a gas mixer, the hydrogen conveying pipe is used for conveying hydrogen, and the trichlorosilane conveying pipe is used for conveying liquid trichlorosilane; the gas-liquid mixer is communicated with the hydrogen conveying pipe and the trichlorosilane conveying pipe and used for mixing the hydrogen and the liquid trichlorosilane, and the gas-liquid mixer is constructed to be used for atomizing a gas-liquid mixture of the hydrogen and the liquid trichlorosilane to form mixed gas; the superheater is used for superheating and vaporizing the atomized mixed gas; and the gas mixer is used for mixing the hydrogen conveyed by the hydrogen conveying pipe with the overheated and vaporized mixed gas. According to the trichlorosilane low-temperature vaporization system, the vaporization temperature of trichlorosilane can be reduced, and energy consumption is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of polysilicon production, and in particular to a trichlorosilane low-temperature vaporization system. Background Art

[0002] The core process of polysilicon production is the reduction process. The main raw materials for reduction are trichlorosilane liquid and hydrogen. The main process of reduction is to heat and vaporize trichlorosilane liquid and hydrogen and then pass them into the reduction furnace for reduction reaction. The current process generally vaporizes and superheats trichlorosilane liquid, mixes it with preheated hydrogen, and then passes it into the reduction furnace. The problem with this process is that the temperature required for the vaporization of trichlorosilane liquid is high, it is easy to liquefy during the transmission process, and it needs to be superheated and vaporized again after liquefaction, which consumes a lot of energy. Utility Model Content

[0003] The present application provides a trichlorosilane low-temperature vaporization system, which can reduce the vaporization temperature of trichlorosilane and reduce energy consumption.

[0004] This application is implemented as follows:

[0005] The present application provides a trichlorosilane low-temperature vaporization system, comprising:

[0006] A hydrogen delivery pipe, wherein the hydrogen delivery pipe is used to deliver hydrogen;

[0007] A trichlorosilane delivery pipe, wherein the trichlorosilane delivery pipe is used to deliver liquid trichlorosilane;

[0008] A gas-liquid mixer, the gas-liquid mixer is connected to the hydrogen delivery pipe and the trichlorosilane delivery pipe, and is used to mix the hydrogen and the liquid trichlorosilane. The gas-liquid mixer can atomize the gas-liquid mixture of the hydrogen and the liquid trichlorosilane;

[0009] a superheater, the superheater being used to superheat and vaporize the atomized mixed gas; and

[0010] A gas mixer is used to mix the hydrogen transported by the hydrogen transport pipe with the superheated vaporized mixed gas.

[0011] In a possible embodiment, the gas-liquid mixer includes a shell, a gas-liquid mixing disk and a plurality of gas-liquid injectors mounted on the gas-liquid mixing disk, wherein the gas-liquid mixing disk is mounted at one end of the shell, and the other end of the shell has a mixed gas outlet, and the mixed gas outlet is connected to the inlet of the superheater; each of the gas-liquid injectors is equipped with a hydrogen branch pipe and a liquid trichlorosilane branch pipe, the hydrogen branch pipe is connected to the hydrogen delivery pipe, and the liquid trichlorosilane branch pipe is connected to the trichlorosilane delivery pipe, and the gas-liquid injector is used to atomize the gas-liquid mixture of the hydrogen and the liquid trichlorosilane to form a mist mixture, and enable the mixed gas to be mixed in the shell and discharged from the mixed gas outlet.

[0012] In a possible implementation manner, the injection port of the gas-liquid injector is disposed at an end of the gas-liquid injector and is close to one end of the mixed gas outlet.

[0013] In a possible implementation manner, the liquid trichlorosilane branch pipe is disposed at an end of the gas-liquid injector away from the injection port, and the hydrogen branch pipe is disposed on the side of the gas-liquid injector.

[0014] In a possible implementation manner, the shell is arranged in a trapezoidal shape, and the inner diameter of the mixed gas outlet is smaller than the outer diameter of the gas-liquid mixing disk.

[0015] In a possible embodiment, the gas-liquid injector includes an injection body installed on the gas-liquid mixing disk, a rotating nozzle installed on the injection body, and a plurality of injection nozzles installed on the rotating nozzle, the rotating nozzle is rotatably connected to the injection body, and the plurality of injection nozzles are arranged along the circumference of the injection body, the injection body has a accommodating cavity inside and is connected to the injection nozzle, the accommodating cavity is connected to the liquid trichlorosilane branch pipe and the trichlorosilane delivery pipe, and the injection direction of the injection nozzle is tangent to the circumference of the injection body.

[0016] In a possible implementation manner, the injection nozzles of the plurality of gas-liquid injectors are staggered in the length direction of the shell, and a plurality of blades are provided in the circumference of the rotating nozzle.

[0017] In a possible implementation, the hydrogen delivery pipe includes a first delivery pipe and a second delivery pipe, the first delivery pipe is connected to the gas-liquid mixer, the second delivery pipe is connected to the gas mixer, and the first delivery pipe is provided with a first control valve.

[0018] In a possible implementation manner, the trichlorosilane delivery pipe is provided with a second control valve.

[0019] In a possible implementation, the superheater is connected to a reduction tail gas inlet pipe, the reduction tail gas inlet pipe is used to supply a low-grade heat source, and the reduction tail gas inlet pipe is provided with a third control valve.

[0020] This application has at least the following beneficial effects:

[0021] The trichlorosilane low-temperature vaporization system of the present application is that hydrogen and trichlorosilane liquid are mixed and atomized in a gas-liquid mixer, and the trichlorosilane liquid is converted into gas and fully mixed with hydrogen to form a mixed gas. The hydrogen can reduce the gas phase partial pressure of trichlorosilane, thereby reducing the vaporization temperature of trichlorosilane. The temperature of the mixed gas being superheated and vaporized in a superheater is reduced, and the energy consumption is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 A schematic diagram of a trichlorosilane low-temperature vaporization system according to an embodiment of the present application;

[0024] Figure 2 This is a schematic structural diagram of a gas-liquid mixer according to an embodiment of the present application;

[0025] Figure 3 This is a schematic diagram of the structure of the gas-liquid mixing disk and the gas-liquid injector according to an embodiment of the present application;

[0026] Figure 4 This is a schematic structural diagram of a gas-liquid injector according to an embodiment of the present application.

[0027] Icons: 10-trichlorosilane low-temperature vaporization system; 11-hydrogen delivery pipe; 111-first delivery pipe; 112-second delivery pipe; 12-trichlorosilane delivery pipe; 13-gas-liquid mixer; 131-shell; 1311-mixed gas outlet; 132-gas-liquid mixing plate; 133-gas-liquid injector; 1331-injection port; 134-hydrogen branch pipe; 135-liquid trichlorosilane branch pipe; 14-superheater; 15-gas mixer; 161-first control valve; 162-second control valve; 163-third control valve; 164-reduction tail gas inlet pipe; 165-reduction tail gas outlet pipe. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0029] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0030] In the description of this application, it should be noted that the terms "inside", "outside", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the application is usually placed when in use, which is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0031] In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "set", "install", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be a connection between the two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances. Example

[0032] This embodiment provides a trichlorosilane low temperature vaporization system 10, please refer to Figure 1 , which includes a hydrogen delivery pipe 11, a trichlorosilane delivery pipe 12, a gas-liquid mixer 13, a superheater 14 and a gas mixer 15.

[0033] The hydrogen delivery pipe 11 is used to deliver hydrogen, and the trichlorosilane delivery pipe 12 is used to deliver liquid trichlorosilane. The hydrogen delivery pipe 11 includes a first delivery pipe 111 and a second delivery pipe 112, and the second delivery pipe 112 is connected to the gas mixer 15. The gas-liquid mixer 13 is connected to the first delivery pipe 111 of the hydrogen delivery pipe 11, and the gas-liquid mixer 13 is also connected to the trichlorosilane delivery pipe 12. Hydrogen enters the gas-liquid mixer 13 through the first delivery pipe 111, and liquid trichlorosilane enters the gas-liquid mixer 13 through the trichlorosilane delivery pipe 12, and hydrogen and liquid trichlorosilane are mixed in the gas-liquid mixer 13.

[0034] Exemplarily, the first delivery pipe 111 is provided with a first control valve 161, and the trichlorosilane delivery pipe 12 is provided with a second control valve 162. By controlling the first control valve 161 and the second control valve 162, the amount of hydrogen and the amount of trichlorosilane entering the gas-liquid mixer 13 can be controlled, and the relative ratio of the two can be controlled. Optionally, the first control valve 161 and the second control valve 162 both include a cut-off valve and a regulating valve.

[0035] In addition, the gas-liquid mixer 13 is configured to atomize the gas-liquid mixture of hydrogen and liquid trichlorosilane to form a mist mixture, the superheater 14 is used to superheat and vaporize the atomized mixed gas, and the gas mixer 15 is used to mix the hydrogen transported by the hydrogen transport pipe 11 with the superheated and vaporized mixed gas.

[0036] The trichlorosilane low-temperature vaporization system 10 of the present application is that hydrogen and trichlorosilane liquid are mixed and atomized in a gas-liquid mixer 13, and the trichlorosilane liquid is converted into gas and fully mixed with hydrogen to form a mixed gas. The hydrogen can reduce the gas phase partial pressure of trichlorosilane, thereby reducing the vaporization temperature of trichlorosilane. The temperature of the mixed gas that is superheated and vaporized in the superheater 14 is reduced, and the energy consumption is low.

[0037] In one embodiment, the superheater 14 is connected to the reduction tail gas inlet pipe 164, and the reduction tail gas inlet pipe 164 is used to supply a low-grade heat source. In this embodiment, the heat source of the superheater 14 uses waste heat to utilize the reduced tail gas after cooling for heating, avoiding the possibility of product contamination by steam heating, while effectively utilizing the low-grade heat source and improving the utilization of waste heat. Exemplarily, the reduction tail gas inlet pipe 164 is provided with a third control valve 163, and the third control valve 163 can control the low-grade heat source to be supplied to the superheater 14. Optionally, the third control valve 163 includes a cut-off valve and a regulating valve.

[0038] In addition, the other end of the superheater 14 is also connected to a reduction tail gas outlet pipe 165 , on which a shut-off valve and a drain valve are provided. The shut-off valve is used to control the discharge of excess reduction tail gas from the superheater 14 .

[0039] For further information, please refer to Figure 2-Figure 4 The gas-liquid mixer 13 includes a shell 131, a gas-liquid mixing plate 132, and a plurality of gas-liquid injectors 133 mounted on the gas-liquid mixing plate 132. The gas-liquid mixing plate 132 is mounted on one end of the shell 131. The other end of the shell 131 has a mixed gas outlet 1311, and the mixed gas outlet 1311 is connected to the inlet of the superheater 14. Each gas-liquid injector 133 is equipped with a hydrogen branch pipe 134 and a liquid trichlorosilane branch pipe 135. The hydrogen branch pipe 134 is connected to the hydrogen delivery pipe 11, and the liquid trichlorosilane branch pipe 135 is connected to the trichlorosilane delivery pipe 12. The hydrogen is distributed to the hydrogen branch pipe 134 through the hydrogen delivery pipe 11, and the trichlorosilane is distributed to the liquid trichlorosilane branch pipe 135 through the trichlorosilane delivery pipe 12. The hydrogen in the hydrogen branch pipe 134 and the trichlorosilane in the liquid trichlorosilane branch pipe 135 are collected in each gas-liquid injector 133. The gas-liquid injector 133 is used to atomize the gas-liquid mixture of hydrogen and liquid trichlorosilane to form a mixed gas, and the mixed gas ejected by each gas-liquid injector 133 is mixed in the housing 131 and discharged from the mixed gas outlet 1311. The hydrogen and trichlorosilane are mixed and atomized by multiple gas-liquid injectors 133, and finally mixed in the housing 131, so that the atomized hydrogen and trichlorosilane can be mixed more evenly.

[0040] Exemplarily, the housing 131 is arranged in a trapezoidal shape, and the inner diameter of the mixed gas outlet 1311 is smaller than the outer diameter of the gas-liquid mixing disk 132. In the direction from the gas-liquid mixing disk 132 to the mixed gas outlet 1311, the inner diameter of the housing 131 gradually decreases, so that the atomized mixed gas sprayed by each gas-liquid injector 133 can be gathered in the direction of the mixed gas outlet 1311, and finally form a certain pressure to be sprayed from the mixed gas outlet 1311.

[0041] Optionally, the liquid trichlorosilane branch pipe 135 is arranged at one end of the gas-liquid injector 133 away from the injection port, and the hydrogen branch pipe 134 is arranged on the side of the gas-liquid injector 133. The liquid trichlorosilane branch pipe 135 and the hydrogen branch pipe 134 are arranged on different sides of the gas-liquid injector 133, which is convenient for arranging the pipelines, and the pipelines are not easily staggered.

[0042] In one embodiment, the injection port 1331 of the gas-liquid injector 133 is disposed at the end of the gas-liquid injector 133 and is close to one end of the mixed gas outlet 1311 .

[0043] In another embodiment, the gas-liquid injector 133 includes an injection body installed on the gas-liquid mixing disk 132, a rotating nozzle installed on the injection body, and a plurality of injection nozzles installed on the rotating nozzle. The rotating nozzle is rotatably connected to the injection body, and the plurality of injection nozzles are arranged along the circumference of the injection body. The injection body has a accommodating cavity inside and is connected to the injection nozzle. The accommodating cavity is connected to the liquid trichlorosilane branch pipe 135 and the trichlorosilane delivery pipe 12. The injection direction of the injection nozzle is tangent to the circumference of the injection body (not shown in the figure).

[0044] Pressurized hydrogen and trichlorosilane are mixed in the injection body. Under the action of pressurized hydrogen, trichlorosilane and hydrogen are ejected from the injection nozzle together and are atomized. Since the injection direction of the injection nozzle is tangent to the circumference of the injection body, under the action of the reaction force, the rotating nozzle connected to multiple injection nozzles rotates around the injection body, so that the atomized mixed gas can be better mixed evenly in the shell 131.

[0045] For example, in order to better atomize the mixed gas, the injection nozzles of the multiple gas-liquid injectors 133 are staggered in the length direction of the shell 131, and multiple blades are arranged in the circumference of the rotating nozzle. When the rotating nozzle rotates, the blades also rotate accordingly, and the injection nozzles of the multiple gas-liquid injectors 133 are staggered in the length direction of the shell 131, so that the atomized mixed gas sprayed by the injection nozzle can more easily hit different blades, and during the rotation of the blades, small droplets can be hit to form smaller droplets, and the atomization effect is better.

[0046] In summary, the trichlorosilane low-temperature vaporization system 10 of the present application is that hydrogen and trichlorosilane liquid are mixed and fully atomized in the gas-liquid mixer 13, and the trichlorosilane liquid is converted into gas and fully mixed with hydrogen to form a mixed gas. The hydrogen can reduce the gas phase partial pressure of trichlorosilane, thereby reducing the vaporization temperature of trichlorosilane. The temperature of the mixed gas is reduced when it is overheated and vaporized in the superheater 14, and the energy consumption is low. In addition, the heat source of the superheater 14 uses waste heat to heat the reduced tail gas after cooling, which avoids the possibility of product contamination by steam heating, and effectively utilizes low-grade heat sources, thereby improving waste heat utilization.

[0047] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A trichlorosilane low temperature vaporization system, characterized in that: include: A hydrogen delivery pipe, wherein the hydrogen delivery pipe is used to deliver hydrogen; A trichlorosilane delivery pipe, wherein the trichlorosilane delivery pipe is used to deliver liquid trichlorosilane; A gas-liquid mixer, the gas-liquid mixer is in communication with the hydrogen delivery pipe and the trichlorosilane delivery pipe, and is used to mix the hydrogen and the liquid trichlorosilane. The gas-liquid mixer is configured to atomize a gas-liquid mixture of the hydrogen and the liquid trichlorosilane to form a mixed gas; A superheater, the superheater is used to superheat and vaporize the atomized mixed gas; the gas-liquid mixer comprises a shell, a gas-liquid mixing disk and a plurality of gas-liquid injectors mounted on the gas-liquid mixing disk, the gas-liquid mixing disk is mounted at one end of the shell, the other end of the shell has a mixed gas outlet, the mixed gas outlet is connected to the inlet of the superheater; each of the gas-liquid injectors is installed with a hydrogen branch pipe and a liquid trichlorosilane branch pipe, the hydrogen branch pipe is connected to the hydrogen delivery pipe, the liquid trichlorosilane branch pipe is connected to the trichlorosilane delivery pipe, the gas-liquid injector is used to atomize the gas-liquid mixture of the hydrogen and the liquid trichlorosilane to form a mixed gas, and the mixed gas can be mixed in the shell and discharged from the mixed gas outlet; as well as A gas mixer is used to mix the hydrogen transported by the hydrogen transport pipe with the superheated vaporized mixed gas.

2. The trichlorosilane low temperature vaporization system according to claim 1, characterized in that: The injection port of the gas-liquid injector is arranged at the end of the gas-liquid injector and is close to one end of the mixed gas outlet.

3. The trichlorosilane low temperature vaporization system according to claim 2, characterized in that: The liquid trichlorosilane branch pipe is arranged at one end of the gas-liquid injector away from the injection port, and the hydrogen branch pipe is arranged at the side of the gas-liquid injector.

4. The trichlorosilane low temperature vaporization system according to any one of claims 1 to 3, characterized in that: The shell is arranged in a trapezoidal shape, and the inner diameter of the mixed gas outlet is smaller than the outer diameter of the gas-liquid mixing disk.

5. The trichlorosilane low temperature vaporization system according to claim 1, characterized in that: The injector comprises an injection body installed on the gas-liquid mixing disk, a rotating nozzle installed on the injection body and a plurality of injection nozzles installed on the rotating nozzle. The rotating nozzle is rotatably connected to the injection body, and the plurality of injection nozzles are arranged along the circumference of the injection body. The injection body has an accommodating cavity inside and is connected to the injection nozzles. The accommodating cavity is connected to the liquid trichlorosilane branch pipe and the trichlorosilane delivery pipe. The injection direction of the injection nozzle is tangent to the circumference of the injection body.

6. The trichlorosilane low temperature vaporization system according to claim 5, characterized in that: The injection nozzles of the plurality of gas-liquid injectors are staggered in the length direction of the shell, and a plurality of blades are arranged in the circumferential direction of the rotary nozzle.

7. The trichlorosilane low temperature vaporization system according to any one of claims 1 to 3, characterized in that: The hydrogen delivery pipe includes a first delivery pipe and a second delivery pipe, the first delivery pipe is communicated with the gas-liquid mixer, the second delivery pipe is communicated with the gas mixer, and the first delivery pipe is provided with a first control valve.

8. The trichlorosilane low temperature vaporization system according to any one of claims 1 to 3, characterized in that: The trichlorosilane delivery pipe is provided with a second control valve.

9. The trichlorosilane low temperature vaporization system according to any one of claims 1 to 3, characterized in that: The superheater is connected to a reduction tail gas inlet pipe, the reduction tail gas inlet pipe is used to supply a low-grade heat source, and the reduction tail gas inlet pipe is provided with a third control valve.

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