Trichlorosilane light component removal system

Abstract

The trichlorosilane light component removal system comprises a rectification module, a separation tower, a condensation device, a material mixing tank, a reaction tank, a finished product collection device, a by-product collection device, a secondary finished product collection device, a secondary by-product collection device and a material conveying pipe arranged between the rectification module, the separation tower, the condensation device, the material mixing tank, the reaction tank, the finished product collection device, the secondary by-product collection device and the secondary by-product collection device. According to the trichlorosilane light component removal system disclosed by the invention, the processes traditionally integrated in the separation tower are dispersed into each independent module and device, so that refined control and efficient management of the processes are realized. Each process can be operated under the optimal condition, the overall production efficiency and the purity of trichlorosilane are improved, in addition, due to the modular design, the maintenance and overhaul work is more convenient, the downtime is shortened, and the maintenance cost is reduced. Meanwhile, a recovery module is also introduced, so that by-products silicon tetrachloride and dichlorosilane in the anti-disproportionation reaction can enter the separation tower again for reaction, and the utilization rate of raw materials is increased.

Description

Technical Field

[0001] The utility model relates to the technical field of distillation and purification, in particular to a trichlorosilane light removal system. Background Art

[0002] The anti-disproportionation reaction involved in the preparation of trichlorosilane mainly refers to the process of generating trichlorosilane (TCS) through an anti-disproportionation reaction using dichlorosilane (DCS) and silicon tetrachloride (STC) in the presence of a catalyst.

[0003] However, the current equipment for preparing trichlorosilane is mainly a separation tower. All steps of the anti-disproportionation reaction are carried out in the separation tower. The by-products of the anti-disproportionation reaction, silicon tetrachloride and silicon dichloride, will affect the purity of the product trichlorosilane. At the same time, all the equipment involved in the reaction are integrated into the separation tower, which will cause inconvenience during maintenance. Utility Model Content

[0004] The utility model aims to solve the problem in the prior art that all steps of the anti-disproportionation reaction are carried out in a separation tower, the by-products of the anti-disproportionation reaction, silicon tetrachloride and dichlorosilane, will affect the purity of the product trichlorosilane, and all devices involved in the reaction are integrated into the separation tower, causing inconvenience during maintenance.

[0005] In order to achieve the above-mentioned purpose, the present application proposes a trichlorosilane light removal system, comprising: a distillation module, a separation tower, a condensing device, a mixing tank, a reaction tank, a finished product collection device, a by-product collection device, a secondary finished product collection device, a secondary by-product collection device, and a feed pipe arranged between the two devices, which are arranged in sequence according to the process steps of preparing trichlorosilane.

[0006] The trichlorosilane light removal system of the present application realizes refined control and efficient management of the process by dispersing these processes traditionally integrated in the separation tower into various independent modules and devices. Each process can be operated under optimal conditions, which improves the overall production efficiency and purity of trichlorosilane, and this modular design makes maintenance and overhaul work more convenient, reducing downtime and maintenance costs. At the same time, a recovery module is also introduced, including: a sub-finished product collection device, a secondary by-product collection device, and two collection devices connected to the feed pipe in the middle section of the separation tower, so that the by-products of the anti-disproportionation reaction, silicon tetrachloride and dichlorodihydrogen silicon, can enter the separation tower again for reaction, thereby improving the utilization rate of the raw materials.

[0007] As an improvement of the above-mentioned condensing device of the present application, in order to effectively collect and discharge the exhaust gas generated during the condensation process and prevent harmful gases from being directly discharged into the environment, a gas supply pipe connected to the exhaust gas emission main pipe is arranged on the top of the condensing device.

[0008] As an improvement of the above-mentioned mixing tank of the present application, in order to maintain the stability of the pressure in the tank during the mixing process and prevent material leakage or uneven mixing due to pressure fluctuations, a balancing pipe connected to the air pipe is provided on the top of the mixing tank.

[0009] As an improvement of the above-mentioned raw material bin in the present application, in order to realize the continuous supply of raw materials and improve the production efficiency and stability, raw material bins are arranged on the top of the mixing tank and the top of the reaction tank.

[0010] Furthermore, in order to ensure that dichlorodihydrogen silicon remains in liquid form during transportation and to improve its reaction effect in the reaction tank, a pressure balancing valve is provided on the feed pipe between the separation tower and the condensing device, the feed pipe between the condensing device and the mixing tank, the feed pipe between the raw material bin and the mixing tank, and the reaction tank.

[0011] Furthermore, in order to allow the condensed material to flow naturally into the mixing tank under the action of gravity and reduce power consumption such as pumping, the installation position of the condensing device should be greater than the installation position of the mixing tank in vertical height.

[0012] Furthermore, in order to provide additional pressure to the reaction tank as needed to promote the anti-disproportionation reaction, a pressurizing module is provided on the reaction tank.

[0013] Furthermore, in order to achieve effective isolation between the premixing device and the key reaction tank for subsequent anti-disproportionation reaction, a bidirectional pressure control valve is installed on the feed pipe connecting the reaction tank and the mixing tank.

[0014] Furthermore, in order to allow the by-products to re-enter the separation tower for further processing and utilization, thereby improving the utilization rate and economic benefits of the raw materials, a feed pipe connected to the by-product collection device is connected at its output end to the middle section of the separation tower.

[0015] Furthermore, in order to improve the collection efficiency of finished products and the recovery efficiency of by-products in the separation tower, the secondary finished product collection device and the secondary by-product collection device are arranged at the bottom section of the separation tower.

[0016] The beneficial effects of this application are:

[0017] 1. The trichlorosilane light removal system of the present application disperses the process traditionally integrated in the separation tower into each independent module and device, realizing the refined control and efficient management of the process. Each process can be operated under optimal conditions, improving the overall production efficiency and purity of trichlorosilane, and this modular design makes maintenance and overhaul work more convenient, reducing downtime and maintenance costs. At the same time, a recovery module is also introduced, so that the by-products of silicon tetrachloride and dichlorodihydrosilane in the anti-disproportionation reaction can enter the separation tower again for reaction, thereby improving the utilization rate of raw materials.

[0018] 2. In the present application, pressure balancing valves are arranged on the feed pipe between the separation tower and the condensing device, the feed pipe between the condensing device and the mixing tank, the feed pipe between the raw material bin and the mixing tank, and the reaction tank. Experiments show that the lightness removal effect of dichlorosilane is better at 0.3MPa. The pressure balancing valves arranged in the above devices can effectively ensure that the separation tower, the condensing device, the mixing tank and the feed pipe between the two maintain the same pressure. By means of pressurization and voltage stabilization, dichlorosilane can always remain in liquid state during the transportation process, which is easier to control than the cooling method.

[0019] 3. The present application is provided with a pressurizing module on the reaction tank. Experiments have shown that the anti-disproportionation reaction has a better reaction effect when it is in an environment of 0.4-0.5MPa in the reaction tank of this system. The pressurizing module and the pressure balancing valve are used to ensure that the pressure in the reaction tank always maintains the most suitable pressure environment for the anti-disproportionation reaction, thereby improving the reaction efficiency.

[0020] 4. In the system of the present application, a two-way pressure control valve is installed on the feed pipe connecting the reaction tank and the mixing tank. The pressure control valve can achieve effective isolation between the premixing device and the key reaction tank for subsequent anti-disproportionation reaction, ensuring that the mixing tank and the reaction tank are in different pressure environments, respectively, to achieve the best premixing effect and reaction effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 This is a schematic structural diagram of a trichlorosilane light removal system in an embodiment of the present application;

[0023] Description of reference numerals:

[0024] 1. Distillation module; 2. Separation tower; 3. Condensation device; 4. Mixing tank; 5. Reaction tank; 6. Finished product collection device; 7. By-product collection device; 8. Secondary finished product collection device; 9. Secondary by-product collection device; 10. Feed pipe; 11. Discharge main pipe; 12. Gas pipe; 13. Balance pipe; 14. Raw material warehouse; 15. Pressure balance valve; 16. Pressurization module; 17. Two-way pressure control valve. DETAILED DESCRIPTION

[0025] The following will be combined with the attached Figure 1The embodiments of the technical solution of the present application are described in detail. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application. In addition, the technical features involved in each embodiment of the present application described below can be combined with each other as long as they do not conflict with each other.

[0026] like Figure 1 A trichlorosilane light removal system of the present application is illustrated, and the trichlorosilane light removal system is sequentially provided with a distillation module 1, a separation tower 2, a condensation device 3, a mixing tank 4, a reaction tank 5, a finished product collection device 6, a by-product collection device 7, a secondary finished product collection device 8, a secondary by-product collection device 9, and a feed pipe 10 connecting these devices according to the process steps of preparing trichlorosilane. These devices are closely connected through the feed pipe to form an efficient production line.

[0027] In one embodiment of the present application, the distillation module 1 is used for preliminarily separating the light components and heavy components in the crude trichlorosilane product, the separation tower 2 is used as the main device for secondary distillation, and is used to further separate the light components and heavy components in the crude trichlorosilane product, the condensing device 3 is used to condense the light component dichlorodihydrosilane output from the top of the separation tower 2 to make it liquid, the mixing tank 4 is a premixing device, which is used to preliminarily mix dichlorodihydrosilane and tetrachlorosilane to improve the efficiency of the subsequent anti-disproportionation reaction, the reaction tank 5 is an important instrument for the anti-disproportionation reaction, and provides a reaction place for the anti-disproportionation reaction, the finished product collection device 6 and the by-product collection device 7 are used to collect the finished products and by-products obtained after the anti-disproportionation reaction, the secondary finished product collection device 8 and the secondary by-product collection device 9 are used to collect the secondary finished products and secondary by-products obtained after the by-products are recycled, and the feed pipe 10 is used to connect the devices involved in the relevant process steps.

[0028] In the prior art, the device for preparing trichlorosilane is mainly a separation tower. All steps of the anti-disproportionation reaction are carried out in the separation tower. The by-products of the anti-disproportionation reaction, silicon tetrachloride and silicon dichloride, will affect the purity of the product trichlorosilane. At the same time, all devices involved in the reaction are integrated into the separation tower, which will cause inconvenience during maintenance.

[0029] In this embodiment, the trichlorosilane light removal system disperses the processes traditionally integrated in the separation tower into various independent modules and devices, realizing refined control and efficient management of the processes. Each process can be operated under optimal conditions, improving the overall production efficiency and purity of trichlorosilane, and this modular design makes maintenance and overhaul work more convenient, reducing downtime and maintenance costs. At the same time, a recovery module is introduced, so that the by-products of the anti-disproportionation reaction, silicon tetrachloride and dichlorodihydrogen silicon, can enter the separation tower again for reaction, thereby improving the utilization rate of the raw materials.

[0030] Continue to refer to Figure 1 In a further embodiment, a gas delivery pipe 12 connected to the exhaust gas main pipe 11 is installed on the top of the condensing device 3. The exhaust gas generated during the condensation process is discharged into the exhaust gas main pipe through the gas delivery pipe, avoiding the direct discharge of harmful gases.

[0031] Further, continue to refer to Figure 1 In order to maintain the pressure in the mixing tank stable, a balance pipe 13 connected to the gas pipe 12 is provided on the top of the mixing tank 4. The balance pipe allows the pressure between the mixing tank and the condensing device to be balanced, preventing material leakage or uneven mixing caused by pressure fluctuations.

[0032] Further, continue to refer to Figure 1 In order to realize the continuous supply of raw materials, a raw material bin 14 is provided on the top of the mixing tank 4 and the top of the reaction tank 5. Among them, the raw material bin 14 provided on the top of the mixing tank 4 contains one of the raw materials for the anti-disproportionation reaction: tetrachlorosilane, and the raw material bin 14 provided on the top of the reaction tank 5 contains the resin as a catalyst. The raw material bin ensures the continuous and stable supply of raw materials, improves the efficiency of the initial mixing of raw materials in the mixing tank 4 and the catalytic performance of the catalyst in the anti-disproportionation reaction, and improves the production efficiency and stability.

[0033] Further, continue to refer to Figure 1 In one embodiment of the present application, in order to ensure the pressure stability of the material during the transportation process, the feed pipe 10 between the separation tower 2 and the condensing device 3, the feed pipe 10 between the condensing device 3 and the mixing tank 4, the feed pipe 10 between the raw material bin 14 and the mixing tank 4, and the reaction tank 5 are all equipped with pressure balance valves 15. These pressure balance valves 15 can automatically adjust the pressure in the pipeline to ensure the stability of the material during the transportation process. At the same time, by adjusting the individual parameters of the pressure balance valve 15, effective isolation between the premixing device and the key reaction tank for subsequent anti-disproportionation reaction can be achieved.

[0034] Furthermore, in order to utilize gravity to reduce power consumption, the installation position of the condensing device 3 is designed to be greater in vertical height than the mixing tank 4. In this way, the condensed material can flow into the mixing tank naturally without the need for additional pumping equipment.

[0035] Furthermore, in order to promote the anti-disproportionation reaction, a pressurizing module 16 is provided on the reaction tank 5. The pressurizing module can provide additional pressure to the reaction tank as required to ensure that the anti-disproportionation reaction is carried out under optimal conditions.

[0036] Furthermore, in order to further achieve effective isolation between the premixing device and the key reaction tank for subsequent anti-disproportionation reaction, a two-way pressure control valve 17 is installed on the feed pipe 10 connecting the reaction tank 5 and the mixing tank 4. The two-way pressure control valve 17 is used to adjust the pressure environment of the reaction tank 5 and the mixing tank 4 to ensure that the pressure of the mixing and anti-disproportionation reactions is always maintained at the optimal state.

[0037] Furthermore, in order to realize the reuse of by-products, the output end of the feed pipe 10 connected to the by-product collecting device 7 is connected to the middle section of the separation tower 2. In this way, the by-products silicon tetrachloride and dichlorosilane can re-enter the separation tower for further processing and utilization, thereby improving the utilization rate of the raw materials.

[0038] Furthermore, in order to improve the collection efficiency of finished products and the recovery efficiency of by-products in the separation tower, a secondary finished product collection device 8 and a secondary by-product collection device 9 are arranged at the bottom section of the separation tower 2, making it easier to collect the heavy components output from the bottom end of the separation tower 2.

[0039] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A trichlorosilane light removal system, characterized in that: include: Arranged in sequence according to the process steps for preparing trichlorosilane are: a distillation module (1), a separation tower (2), a condensing device (3), a mixing tank (4), a reaction tank (5), a finished product collecting device (6), a by-product collecting device (7), a secondary finished product collecting device (8), a secondary by-product collecting device (9), and a feed pipe (10) arranged between the two devices.

2. The trichlorosilane light removal system according to claim 1, characterized in that: The top of the condensing device (3) is provided with a gas delivery pipe (12) connected to the exhaust gas exhaust main pipe (11).

3. The trichlorosilane light removal system according to claim 1, characterized in that: A balance pipe (13) connected to the air delivery pipe (12) is arranged on the top of the mixing tank (4).

4. The trichlorosilane light removal system according to claim 1, characterized in that: A raw material bin (14) is provided on the top of the mixing tank (4) and the top of the reaction tank (5).

5. The trichlorosilane light removal system according to claim 1 or 4, characterized in that: The feed pipe (10) between the separation tower (2) and the condensation device (3), the feed pipe (10) between the condensation device (3) and the mixing tank (4), the feed pipe (10) between the raw material bin (14) and the mixing tank (4), and the reaction tank (5) are all provided with a pressure balance valve (15).

6. The trichlorosilane light removal system according to claim 1, characterized in that: The installation position of the condensing device (3) is greater in vertical height than the installation position of the mixing tank (4).

7. The trichlorosilane light removal system according to claim 1, characterized in that: The reaction tank (5) is provided with a pressurizing module (16).

8. The trichlorosilane light removal system according to claim 1, characterized in that: A bidirectional pressure control valve (17) is installed on the feed pipe (10) connecting the reaction tank (5) and the mixing tank (4).

9. The trichlorosilane light removal system according to claim 1, characterized in that: A feed pipe (10) connected to the by-product collecting device (7) has its output end connected to the middle section of the separation tower (2).

10. The trichlorosilane light removal system according to claim 1, characterized in that: The secondary finished product collecting device (8) and the secondary by-product collecting device (9) are arranged at the bottom section of the separation tower (2).

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