Trichlorosilane light component removal mixing device

Abstract

The utility model provides a trichlorosilane light component removal mixing device. The device comprises a mixing tank; the first material conveying pipe is connected with the separating tower and the material mixing tank, and the output end of the first material conveying pipe is connected to the top of the material mixing tank; the raw material bin is arranged at the top of the mixing tank; the second conveying pipe is connected with the mixing tank and the raw material bin; the nitrogen tank is arranged at the bottom of the mixing tank; the third conveying pipe is connected with the mixing tank and the nitrogen tank; and the discharging pipe is arranged at the bottom of the mixing tank. According to the trichlorosilane light component removal mixing device, by integrating the mixing tank, the raw material bin, the nitrogen tank and the multiple conveying pipes, premixing of raw materials needed for preparing trichlorosilane is achieved, and the mixing uniformity of the raw materials is ensured; meanwhile, a nitrogen tank and a corresponding pipeline are arranged to be connected with the material mixing tank to form an air cushion layer, so that a pressure buffering effect is achieved, the pressure in the material mixing tank is stabilized, and dichlorosilane is promoted to be more effectively converted into a liquid state in the environment that the pressure of the material mixing tank is stable.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of polysilicon production especially relates to a trichlorosilane light removal mixing device. BACKGROUND

[0002] Trichlorosilane (SiHCl3) is an important organosilicon monomer, and its purification process mainly depends on rectification technology. Rectification is a process of separating mixtures by heating, evaporation, condensation and collection based on the difference in boiling points between substances. In the purification of trichlorosilane, the light removal mixing device is mainly used to remove low-boiling light component impurities such as dichlorodisilane and boron trichloride to improve the purity of trichlorosilane. Before the reverse disproportionation reaction for preparing trichlorosilane, in order to better improve the utilization rate of raw materials and reduce the generation of by-products, it is necessary to pre-mix dichlorodisilane and silicon tetrachloride required for preparing trichlorosilane.

[0003] However, the device design for pre-mixing dichlorodisilane and silicon tetrachloride in the current technical field has limitations, and its structure is relatively rough, which cannot fully meet the process requirements. In view of the extremely low boiling point of dichlorodisilane (only 8.2℃), the traditional method relies on pressurization to improve the liquid stability of dichlorodisilane at room temperature, but such a simple device cannot effectively promote the conversion of dichlorodisilane into a liquid state that is easy to participate in the reaction at room temperature.

[0004] Furthermore, such a simple device often cannot maintain the stability of the internal pressure of the pre-mixing device during the process of trying to convert dichlorodisilane into a liquid state. UTILITY MODEL CONTENTS

[0005] The utility model aims to solve the problem that the pre-mixing device cannot convert dichlorodisilane into a liquid state at room temperature and maintain stable pressure in the prior art.

[0006] In order to achieve the above-mentioned purpose, the present application provides a trichlorosilane light removal mixing device, which comprises a mixing tank, a first feed pipe connecting the separation tower and the mixing tank, wherein the output end of the first feed pipe is connected to the top of the mixing tank, a raw material bin arranged at the top of the mixing tank, a second feed pipe connecting the mixing tank and the raw material bin, a nitrogen tank arranged at the bottom of the mixing tank, a third feed pipe connecting the mixing tank and the nitrogen tank, and a discharge pipe arranged at the bottom of the mixing tank.

[0007] The trichlorosilane light removal mixing device of the application realizes the premixing of the raw materials required for the preparation of trichlorosilane by integrating the mixing tank, the raw material bin, the nitrogen tank and the plurality of material conveying pipes, and ensures the uniformity of the raw material mixing; meanwhile, the nitrogen tank is connected to the mixing tank through the corresponding pipeline, the nitrogen enters the top space of the mixing tank at a constant flow rate and pressure, forms an air cushion layer, plays a pressure buffering role, is used for stabilizing the pressure in the mixing tank, and simultaneously promotes the more effective conversion of dichlorodisilane into liquid in the environment with stable pressure in the mixing tank.

[0008] Further, in order to improve the efficiency of the nitrogen pressure stabilization, the output end of the third material conveying pipe is connected to the top end of the mixing tank.

[0009] As an improvement of the above-mentioned material conveying pipe of the application, the first material conveying pipe, the second material conveying pipe, the third material conveying pipe and the tail gas discharge main pipe are provided with pressure balance valves. The pressure balance valves arranged on each material conveying pipe can adjust the pressure between each material conveying pipe and the components connected thereto, and ensure that the pressure in the entire trichlorosilane light removal mixing device remains equal and stable.

[0010] As an improvement of the above-mentioned balance pipe of the application, in order to maintain the stability of the pressure in the tank during the mixing process, the top of the mixing tank is provided with a balance pipe, the input end of the balance pipe is connected to the top of the mixing tank, and the output end of the balance pipe is arranged between the pressure balance valve on the tail gas discharge main pipe and the mixing tank.

[0011] Further, in order to enable the operator to monitor the pressure change in the raw material conveying process in real time, a pressure gauge is arranged between the raw material bin and the pressure balance valve on the second material conveying pipe.

[0012] Further, in order to provide emergency support when the main pipeline for supplying nitrogen fails, a third material conveying sub-pipe is arranged between the pressure balance valve on the third material conveying pipe and the mixing tank.

[0013] Further, in order to maintain the stability of the mixing tank during the process of the nitrogen entering the mixing tank, a pressure relief valve is arranged at the end of the third material conveying sub-pipe.

[0014] Further, in order to realize the effective isolation between the premixing device and the key reaction tank for subsequent reverse disproportionation reaction, a gate valve is arranged on the discharge pipe.

[0015] The application has the following beneficial effects:

[0016] 1. The trichlorosilane light removal mixing device of the present application, by integrating the mixing tank, raw material bin, nitrogen tank and multiple feeding pipes, realizes the premixing of the raw materials required for preparing trichlorosilane, and ensures the uniformity of the raw material mixing; meanwhile, the nitrogen tank is connected with the corresponding pipeline to the mixing tank, nitrogen enters the top space of the mixing tank at a constant flow rate and pressure, forms an air cushion layer, plays a role of pressure buffer, is used for stabilizing the pressure in the mixing tank, and at the same time promotes the more effective conversion of dichlorodisilane into liquid in the environment with stable pressure of the mixing tank.

[0017] 2. The nitrogen tank of the present application is provided with a pressure gauge, the conveying pipeline connected with the mixing tank is provided with a third feeding branch pipe, and the release speed of nitrogen can be effectively inferred according to the value on the pressure gauge; when the release speed is too large to cause unstable pressure, the pressure relief can be carried out through the pressure relief valve on the third feeding branch pipe, so as to ensure the stability in the nitrogen conveying process.

[0018] 3. The discharge pipe of the present application is provided with a gate valve, which can effectively isolate the mixing tank and the reaction tank; since the optimal pressure of mixing is near 0.3MPA and the optimal pressure of the reverse disproportionation reaction is near 0.5MPA, isolating the mixing tank and the reaction tank can improve the mixing efficiency without affecting the subsequent reverse disproportionation reaction. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiments will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0020] Figure 1 It is a structure schematic view of a trichlorosilane light removal mixing device in the embodiments of the present application.

[0021] Figure 2 It is an installation schematic view of the balance pipe in the embodiments of the present application.

[0022] MARKING OF DRAWINGS:

[0023] 1, mixing tank; 2, first feeding pipe; 3, raw material bin; 4, second feeding pipe; 5, nitrogen tank; 6, third feeding pipe; 7, tail gas discharge main pipe; 8, pressure balance valve; 9, balance pipe; 10, pressure gauge; 11, third feeding branch pipe; 12, pressure relief valve; 13, discharge pipe; 14, gate valve. DETAILED DESCRIPTION

[0024] The specific embodiments of the present application will be described below with reference to the accompanying drawings. Figures 1-2The embodiments of the technical solutions of the present application are described in detail. The following embodiments are only used to more clearly illustrate the technical solutions of the present application, and therefore only serve as examples, and cannot limit the protection scope of the present application. In addition, the technical features involved in the various embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0025] As Figures 1-2 A trichlorosilane light removal mixing device is illustrated, which includes a mixing tank 1, a first feed pipe 2 connecting the separation tower and the mixing tank 1, wherein the output end of the first feed pipe 2 is connected to the top of the mixing tank 1, a raw material bin 3 arranged at the top of the mixing tank 1, a second feed pipe 4 connecting the mixing tank 1 and the raw material bin 3, a nitrogen tank 5 arranged at the bottom of the mixing tank 1, a third feed pipe 6 connecting the mixing tank 1 and the nitrogen tank 5, and a discharge pipe 13 arranged at the bottom of the mixing tank 1.

[0026] In an embodiment of the present application, the mixing tank 1 is the core component of the entire device, and a connecting hole is designed at the top thereof for receiving input from the first feed pipe 2. One end of the first feed pipe 2 is connected to the separation tower, and the other end is directly inserted into the top of the mixing tank 1, ensuring that the raw materials such as dichlorodisilane obtained from the separation tower can smoothly enter the mixing tank.

[0027] Continuing to refer to Figure 1 In a further embodiment, a raw material bin 3 is further arranged at the top of the mixing tank 1 for storing other raw materials that need to be mixed. The raw material bin 3 is connected to the mixing tank 1 through the second feed pipe 4, and a pressure balance valve 8 is installed on the second feed pipe 4 to adjust and control the pressure when the raw materials enter the mixing tank, ensuring smooth delivery of the raw materials. At the same time, in order to monitor the pressure change in the raw material delivery process in real time, a pressure gauge 10 is arranged between the raw material bin 3 and the pressure balance valve 8 on the second feed pipe 4, and the operator can monitor and adjust the system pressure by observing the pressure gauge reading.

[0028] Continuing to refer to Figure 1 In a further embodiment, in order to stabilize the pressure in the mixing tank 1, a nitrogen tank 5 is arranged at the bottom of the mixing tank 1. The nitrogen tank 5 is connected to the mixing tank 1 through the third feed pipe 6, and the output end of the third feed pipe 6 is directly connected to the top end of the mixing tank 1, so that nitrogen can enter the top space of the mixing tank at a constant flow rate and pressure, forming an air cushion layer, which effectively buffers and stabilizes the pressure in the mixing tank. Similarly, a pressure balance valve 8 is also installed on the third feed pipe 6 to further ensure the stability and safety of the nitrogen delivery process.

[0029] Continuing to refer to Figure 1In a further embodiment, in order to cope with possible failure of the nitrogen supply pipeline, the device is additionally provided with a third material conveying branch pipe 11 between the pressure balance valve 8 on the third material conveying pipe 6 and the mixing tank 1, as an emergency backup pipeline. The end of the third material conveying branch pipe 11 is also provided with a pressure relief valve 12, which can be opened to quickly release pressure when the nitrogen conveying pressure abnormally rises, preventing excessive pressure in the mixing tank from causing safety hazards.

[0030] Please refer to Figure 2 In a further embodiment, in addition, the top of the mixing tank 1 is also provided with a balance pipe 9, the input end of which is connected to the top of the mixing tank, and the output end is arranged between the pressure balance valve 8 on the tail gas discharge main pipe 7 and the mixing tank 1. The arrangement of the balance pipe 9 helps to further maintain the stability of the pressure in the tank during the mixing process, ensuring the smooth progress of the mixing process.

[0031] Please refer to Figure 1 In a further embodiment, the bottom of the mixing tank 1 is provided with a discharge pipe 13 for discharging the uniformly mixed raw materials to the subsequent reaction tank for disproportionation reaction. The discharge pipe 13 is provided with a gate valve 14, and by controlling the opening and closing of the gate valve, the mixing tank and the reaction tank can be effectively isolated to avoid pressure interference between them, so as to ensure the mixing efficiency while not affecting the optimal pressure conditions of the subsequent disproportionation reaction.

[0032] In summary, the trichlorosilane light removal mixing device of the present application introduces a nitrogen tank 5 to form a nitrogen gas cushion layer in the upper part of the mixing tank 1, to reduce the pressure fluctuation during the premixing process in the mixing tank. At the same time, pressure balance valves 8 and corresponding pressure gauges 10 are arranged on the pipelines connected to the other raw material input ports, to detect the pressure fluctuation on each material conveying pipeline. If an abnormality occurs, the pressure in the material conveying pipeline can be adjusted in time through the pressure balance valve 8. Finally, the gate valve 14 arranged on the discharge pipe 13 effectively isolates the mixing device from the subsequent device, providing an optimal pressure environment for mixing.

[0033] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A trichlorosilane light removal mixing device, characterized in that, The utility model relates to a kind of raw material mixing tank, including: Mixing tank (1);First feed pipe (2) connecting separation tower and mixing tank (1), wherein the output end of first feed pipe (2) is connected at the top of mixing tank (1);Raw material bin (3) is arranged at the top of mixing tank (1);Second feed pipe (4) connecting mixing tank (1) and raw material bin (3);Nitrogen tank (5) is arranged at the bottom of mixing tank (1);Third feed pipe (6) connecting mixing tank (1) and nitrogen tank (5) and discharge pipe (13) arranged at the bottom of mixing tank (1);Tail gas discharge header (7) is connected at the top of mixing tank (1).

2. The trichlorosilane light ends removal and mixture device of claim 1, wherein, The output end of the third feed pipe (6) is connected to the top end of the mixing tank (1).

3. The trichlorosilane light ends removal and mixture device of claim 1, wherein, Pressure balance valves (8) are provided on the first feed pipe (2), the second feed pipe (4), the third feed pipe (6), and the tail gas discharge header (7).

4. The trichlorosilane light ends removal and mixture device of claim 1, wherein, A balance pipe (9) is provided at the top of the mixing tank (1), with the input end of the balance pipe (9) connected to the top of the mixing tank (1), and the output end of the balance pipe (9) provided between the pressure balance valve (8) on the tail gas discharge header (7) and the mixing tank (1).

5. The trichlorosilane light-removal mixing device according to claim 1 or 3, characterized in that, A pressure gauge (10) is provided between the raw material bin (3) and the pressure balance valve (8) on the second feed pipe (4).

6. The trichlorosilane light ends removal and mixture device of claim 4, wherein, A third feed sub-pipe (11) is provided between the pressure balance valve (8) on the third feed pipe (6) and the mixing tank (1).

7. The trichlorosilane light ends removal and mixture device of claim 6, wherein, A pressure relief valve (12) is provided at the end of the third feed sub-pipe (11).

8. The trichlorosilane light ends removal and mixture device of claim 1, wherein, A gate valve (14) is provided on the discharge pipe (13).

Images