Nitrogen protection system of reduction furnace
By adding a hard nitrogen purge pipeline in front of the exhaust gas cut-off valve of the reduction furnace and performing program control, the explosion risk caused by chlorosilane aggregation at the exhaust pipe outlet and the risk of misoperation of manual replacement is solved, and a safer exhaust gas treatment and replacement process is achieved.
Patent Information
- Application Number
- CN202421620662.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-10
- Publication Date
- 2025-06-06
- Estimated Expiration
- 2034-07-10
AI Technical Summary
After the furnace is removed, chlorosilane will accumulate at the outlet of the exhaust pipe, resulting in a local explosion risk. There is a risk of misoperation and inadequate replacement when manually replacing the nitrogen hose.
Add a hard nitrogen purge pipeline before the exhaust gas cut-off valve of the reduction furnace and perform program control to ensure that the nitrogen purge pipeline automatically opens and closes under specific conditions.
It effectively avoids the risk of local explosion at the exhaust pipe mouth, reduces the risk of manual misoperation and inadequate replacement, and completely eliminates the related safety hazards after dismantling the furnace.
Smart Images
Figure CN222951531U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of tail gas treatment in a reduction section of polysilicon production, in particular to a nitrogen protection system for a reduction furnace. Background Art
[0002] At present, after the reduction furnace is dismantled, the exhaust gas main shut-off valve will inevitably have a small amount of leakage as the running time increases, and the exposed chlorosilane will continue to accumulate at the exhaust pipe mouth. When employees work on the chassis during non-production time periods, the operation will cause fire at the exhaust pipe mouth of the chassis, which will lead to a local explosion at the exhaust pipe mouth and cause danger. Summary of the invention
[0003] In view of the above situation, in order to overcome the defects of the prior art, the purpose of the utility model is to provide a nitrogen protection system for a reduction furnace, which solves the technical problem that after the reduction furnace is dismantled, the exposed chlorosilane will continue to accumulate at the exhaust pipe outlet, and when employees are working on the chassis, the exhaust pipe outlet has a local explosion risk.
[0004] In order to achieve the above purpose, the utility model provides the following technical solutions:
[0005] A nitrogen protection system for a reduction furnace comprises: a gas supply unit connected to an air inlet of the reduction furnace; a tail gas pipeline connected to an air outlet of the reduction furnace, wherein a first valve is arranged on the tail gas pipeline; a nitrogen purge pipeline is connected between the air outlet of the reduction furnace and the first valve, wherein the other end of the nitrogen purge pipeline is connected to a nitrogen pipeline of the gas supply unit, wherein a control valve is arranged on the nitrogen purge pipeline.
[0006] The utility model can effectively avoid the danger of local explosion at the tail gas pipe mouth by adding a hard nitrogen purge pipeline in front of the tail gas shut-off valve of the reduction furnace and performing program control. It can also avoid the risk of manual misoperation and inadequate replacement during manual replacement through a nitrogen hose after the furnace is dismantled, thereby completely eliminating the risk.
[0007] Optionally, the control valve, the first valve and the valve on the gas supply unit are all electrically connected to a control system, and the control system regulates the opening and closing of the control valve according to a preset furnace pressure of the reduction furnace and the opening and closing state of the valve.
[0008] Optionally, the gas outlet end of the reduction furnace is connected to a tail gas network, the tail gas pipeline is connected to the gas outlet end of the reduction furnace through the tail gas network, and one end of the nitrogen purge pipeline is connected to the tail gas pipeline between the tail gas network and the first valve.
[0009] Optionally, the gas supply unit includes: a mixed gas feed pipeline connected to the air inlet end of the reduction furnace, and a second valve is arranged on the mixed gas feed pipeline; a nitrogen pipeline, one end of which is away from the nitrogen supply device and is connected between the air inlet end of the reduction furnace and the second valve, and a third valve is arranged on the nitrogen pipeline; wherein one end of the nitrogen purge pipeline is connected between the nitrogen supply device and the third valve.
[0010] Optionally, the gas supply unit further includes: a mixer, an outlet of which is connected to the mixed gas feed pipeline; a hydrogen pipeline and a silane pipeline are connected to the mixer; a fourth valve is provided on the hydrogen pipeline; and a fifth valve is provided on the silane pipeline.
[0011] Optionally, a rinsing pipeline is connected between the gas outlet of the reduction furnace and the first valve, a sixth valve is provided on the rinsing pipeline, and one end of the nitrogen purge pipeline is connected to the tail gas pipeline between the first valve and the rinsing pipeline.
[0012] Optionally, a first regulating valve is provided on the nitrogen pipeline, a second regulating valve is provided on the hydrogen pipeline, and a third regulating valve is provided on the silane pipeline, and the first regulating valve, the second regulating valve and the third regulating valve are all electrically connected to a control system.
[0013] Optionally, the control valve, the first valve, the second valve, the third valve, the fourth valve, the fifth valve and the sixth valve are all electrically connected to a control system, and the control system regulates the opening and closing of the control valve according to the furnace pressure of the reduction furnace and the opening and closing status of the first valve, the second valve, the third valve, the fourth valve, the fifth valve and the sixth valve. When the furnace pressure is less than 5KPA and the first valve, the second valve, the third valve, the fourth valve, the fifth valve and the sixth valve are all closed, the control system regulates the control valve to open.
[0014] Compared with the prior art, the beneficial effects of the utility model are:
[0015] The utility model can effectively avoid the danger of local explosion at the tail gas pipe mouth by adding a hard nitrogen purge pipeline in front of the tail gas shut-off valve of the reduction furnace and performing program control. It can also avoid the risk of manual misoperation and inadequate replacement during manual replacement through a nitrogen hose after the furnace is dismantled, thereby completely eliminating the risk. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.
[0017] Figure 1 It is a structural schematic diagram of the utility model.
[0018] Figure numerals: 1. reduction furnace; 11. tail gas network; 2. tail gas pipeline; 21. first valve; 3. nitrogen purge pipeline; 31. control valve; 4. mixed gas feed pipeline; 41. second valve; 5. nitrogen pipeline; 51. third valve; 52. first regulating valve; 6. mixer; 7. hydrogen pipeline; 71. fourth valve; 72. second regulating valve; 8. silane pipeline; 81. fifth valve; 82. third regulating valve; 9. rinsing pipeline; 91. sixth valve. DETAILED DESCRIPTION
[0019] In the following, only some exemplary embodiments are briefly described. As those skilled in the art will appreciate, the described embodiments may be modified in various ways without departing from the spirit or scope of the embodiments of the present invention. Therefore, the drawings and descriptions are considered to be exemplary and non-restrictive in nature.
[0020] In the description of the embodiments of the present utility model application, it needs to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", "end", "side", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present utility model application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present utility model application.
[0021] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present utility model application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.
[0022] In the embodiments of the present utility model application, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like 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 mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present utility model application can be understood according to the specific circumstances.
[0023] In the embodiments of the utility model application, unless otherwise clearly specified and limited, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through another feature between them. Moreover, the first feature being "above", "above" and "above" the second feature includes the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature includes the first feature being directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.
[0024] The disclosure below provides many different embodiments or examples for realizing different structures of the embodiments of the utility model application. In order to simplify the disclosure of the embodiments of the utility model application, the components and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the embodiments of the utility model application. In addition, the embodiments of the utility model application can repeat reference numbers and / or reference letters in different examples, and this repetition is for the purpose of simplification and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed.
[0025] The embodiments of the present utility model are described in detail below with reference to the accompanying drawings.
[0026] At present, after the reduction furnace is dismantled, the exhaust gas main shut-off valve will inevitably leak a small amount as the running time increases, and the exposed chlorosilane will continue to accumulate at the exhaust pipe mouth. When employees work on the chassis during non-production time periods, the chassis exhaust pipe mouth will ignite due to operation, which will lead to a local explosion at the exhaust pipe mouth. In order to solve the above problems, after the reduction furnace is dismantled, our company's operators connect a temporary nitrogen hose to the exhaust pipe mouth for continuous purging protection, but this control method is only a temporary emergency measure. The nitrogen hose is not reliable only at the pipe mouth. It can only dilute the chlorosilane at the pipe mouth, but cannot dilute the chlorosilane in the pipeline. Once a large amount of chlorosilane in the pipe is discharged due to external force, the necessary protection measures will be lost. At the same time, the hose will fall off due to misoperation of the personnel, making it impossible to control the risk.
[0027] like Figure 1 As shown, the embodiment of the utility model application provides a nitrogen protection system for a reduction furnace to solve the above problems. The protection system comprises: a gas supply unit connected to the gas inlet end of the reduction furnace 1 and a tail gas pipeline 2 connected to the gas outlet end of the reduction furnace 1, and a nitrogen purge pipeline 3 connected to the tail gas pipeline 2 and the nitrogen pipeline 5 of the gas supply unit.
[0028] Specifically,
[0029] The gas outlet end of the reduction furnace 1 is connected to a tail gas pipeline 2 , and a first valve 21 is provided on the tail gas pipeline 2 .
[0030] The gas supply unit comprises a mixed gas feed pipeline 4 and a nitrogen pipeline 5 connected to the mixed gas feed pipeline 4 . A second valve 41 is provided on the mixed gas feed pipeline 4 , and a third valve 51 is provided on the nitrogen pipeline 5 .
[0031] One end of the nitrogen purge pipeline 3 is connected to the tail gas pipeline 2 between the gas outlet of the reduction furnace 1 and the first valve 21 , and the other end is connected to the nitrogen pipeline 5 , and a control valve 31 is provided on the nitrogen purge pipeline 3 .
[0032] In one implementation scenario, in this scenario, after the furnace is opened, the control valve 31 is automatically opened for purge.
[0033] In order to prevent pressure reversal due to failure to open the furnace, in another implementation scenario, in this scenario, the system is program-controlled. When the furnace pressure of the reduction furnace 1 is less than 5KPA and the first valve 21 on the tail gas pipeline 2 and the valves on the gas supply unit are all closed, the control valve (nitrogen purge valve) on the nitrogen purge pipeline is automatically opened. When the above conditions are not met, the control valve is automatically closed. By adding a rigid nitrogen purge pipeline in front of the tail gas shut-off valve of the tail gas pipeline network 11 and performing program control, the risk of manual misoperation and inadequate replacement during manual replacement through a nitrogen hose after the furnace is dismantled can be avoided.
[0034] Optionally, the outlet of the reduction furnace 1 is connected to a tail gas network 11, and one end of the tail gas pipeline 2 is connected to the outlet of the reduction furnace 1 through the tail gas network 11. One end of the nitrogen purge pipeline 3 is connected to the tail gas pipeline 2 between the tail gas network 11 and the first valve 21.
[0035] Optionally, the first valve 21, the control valve 31 and the valve on the gas supply unit are all electrically connected to a control system, and the control system regulates the opening and closing of the control valve 31 according to a preset furnace pressure of the reduction furnace 1 and the opening and closing state of the valve.
[0036] Optionally, the nitrogen purge pipeline 3 uses a DN8 nitrogen purge pipe.
[0037] Optionally, one end of the mixed gas feed pipeline 4 is connected to the air inlet end of the reduction furnace 1, one end of the nitrogen pipeline 5 is connected to the mixed gas feed pipeline 4 between the air inlet end of the reduction furnace 1 and the second valve 41, and the other end of the nitrogen pipeline 5 is connected to the nitrogen supply device. One end of the nitrogen purge pipeline 3 is connected to the tail gas pipeline 2 between the tail gas network 11 and the first valve 21, and the other end is connected to the nitrogen pipeline 5 between the nitrogen supply device and the third valve 51.
[0038] In one embodiment, the gas supply unit further includes a mixer 6 connected to the mixed gas feed pipeline 4 , and a hydrogen pipeline 7 and a silane pipeline 8 connected to the mixer 6 .
[0039] Optionally, the outlet at the lower end of the mixer 6 is connected to the mixed gas feed pipeline 4, and the inlet of the mixer 6 is connected to the hydrogen pipeline 7 and the silane pipeline 8, and the hydrogen pipeline 7 is provided with a fourth valve 71, and the silane pipeline 8 is provided with a fifth valve 81. When in use, hydrogen and silane enter the mixer 6 through the hydrogen pipeline 7 and the silane pipeline 8 respectively for mixing, and the mixed gas enters the reduction furnace 1 through the mixed gas feed pipeline 4. In an implementation scenario, the gas after hydrogen and silane are mixed by the mixer 6 enters the reduction furnace 1 by opening the second valve 41, and by opening the third valve 51 on the nitrogen pipeline 5, the nitrogen enters the reduction furnace 1 for replacement after the hydrogen and chlorosilane are stopped.
[0040] In one embodiment, a rinsing pipeline 9 is connected between the gas outlet of the reduction furnace 1 and the first valve 21, that is, one end of the rinsing pipeline 9 is connected to the tail gas pipeline 2 between the first valve 21 and the tail gas network 11. A sixth valve 91 is provided on the rinsing pipeline 9, and one end of the nitrogen purge pipeline 3 is connected to the tail gas pipeline 2 between the first valve 21 and the rinsing pipeline 9.
[0041] Optionally, the first valve 21 is a tail gas cut-off valve, the second valve 41 is a mixed gas cut-off valve, the third valve 51 is a nitrogen cut-off valve, the fourth valve 71 is a hydrogen cut-off valve, the fifth valve 81 is a silane cut-off valve, and the sixth valve 91 is a rinse cut-off valve.
[0042] Optionally, the first valve 21, the second valve 41, the third valve 51, the fourth valve 71 and the fifth valve 81 are all pneumatic shut-off valves or electric shut-off valves.
[0043] Optionally, the control valve 31, the first valve 21, the second valve 41, the third valve 51, the fourth valve 71, the fifth valve 81 and the sixth valve 91 are all electrically connected to the control system. When in use, a control program is preset in the control system, and the control system controls the opening and closing of the control valve 31, the first valve 21, the second valve 41, the third valve 51, the fourth valve 71, the fifth valve 81 and the sixth valve 91.
[0044] Optionally, a first regulating valve 52 is provided on the nitrogen pipeline 5, a second regulating valve 72 is provided on the hydrogen pipeline 7, and a third regulating valve 82 is provided on the silane pipeline 8. The first regulating valve 52 is a nitrogen regulating valve, the second regulating valve 72 is a hydrogen regulating valve, and the third regulating valve 82 is a silane regulating valve.
[0045] Optionally, the first regulating valve 52 , the second regulating valve 72 and the third regulating valve 82 are all electrically connected to a control system and their opening and closing are controlled by the control system.
[0046] A method for using a nitrogen protection system for a reduction furnace: after a reduction furnace 1 is started, a control valve 31 on a nitrogen purge pipeline 3 is automatically opened for purge.
[0047] A method for using a nitrogen protection system for a reduction furnace: presetting control conditions in a control system, the control conditions being: furnace pressure <5KPA, and a mixed gas shut-off valve, an exhaust gas shut-off valve, a rinse shut-off valve, feed hydrogen, silane, and a system nitrogen valve are all closed; when a signal received by the control system satisfies the above control regulation, a control valve of a nitrogen purge pipeline is automatically opened, and when the above conditions are not met, the control valve is automatically closed.
[0048] Parts not described in detail in this embodiment are well-known techniques in the art.
[0049] The above is only a specific implementation of the utility model, but the protection scope of the utility model is not limited thereto. Any technician familiar with the technical field can easily think of various changes or substitutions within the technical scope disclosed by the utility model, which should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model should be based on the protection scope of the claims.
Claims
1. A nitrogen protection system for a reduction furnace, characterized in that: include: A gas supply unit connected to the gas inlet end of the reduction furnace; A tail gas pipeline is connected to the gas outlet of the reduction furnace, and a first valve is arranged on the tail gas pipeline; A nitrogen purge pipeline is connected between the gas outlet end of the reduction furnace and the first valve, the other end of the nitrogen purge pipeline is connected to the nitrogen pipeline of the gas supply unit, and a control valve is arranged on the nitrogen purge pipeline.
2. A reduction furnace nitrogen protection system according to claim 1, characterized in that: The control valve, the first valve and the valve on the gas supply unit are all electrically connected to a control system, and the control system regulates the opening and closing of the control valve according to a preset furnace pressure of the reduction furnace and the opening and closing state of the valve.
3. A reduction furnace nitrogen protection system according to claim 1, characterized in that: The gas outlet of the reduction furnace is connected to a tail gas network, the tail gas pipeline is connected to the gas outlet of the reduction furnace through the tail gas network, and one end of the nitrogen purge pipeline is connected to the tail gas pipeline between the tail gas network and the first valve.
4. A reduction furnace nitrogen protection system according to claim 1, 2 or 3, characterized in that: The air supply unit comprises: A mixed gas feed pipeline connected to the gas inlet end of the reduction furnace, and a second valve is provided on the mixed gas feed pipeline; A nitrogen pipeline, one end of which is away from the nitrogen supply device and is connected between the air inlet end of the reduction furnace and the second valve, and a third valve is provided on the nitrogen pipeline; Wherein, one end of the nitrogen purge pipeline is connected between the nitrogen supply device and the third valve.
5. A reduction furnace nitrogen protection system according to claim 4, characterized in that: The air supply unit also includes: a mixer, the outlet of which is connected to the mixed gas feed pipeline; The mixer is connected with a hydrogen pipeline and a silane pipeline; A fourth valve is provided on the hydrogen pipeline; The silane pipeline is provided with a fifth valve.
6. A reduction furnace nitrogen protection system according to claim 5, characterized in that: A rinsing pipeline is connected between the gas outlet end of the reduction furnace and the first valve, a sixth valve is arranged on the rinsing pipeline, and one end of the nitrogen purge pipeline is connected to the tail gas pipeline between the first valve and the rinsing pipeline.
7. A reduction furnace nitrogen protection system according to claim 5, characterized in that: The nitrogen pipeline is provided with a first regulating valve, the hydrogen pipeline is provided with a second regulating valve, and the silane pipeline is provided with a third regulating valve. The first regulating valve, the second regulating valve and the third regulating valve are all electrically connected to a control system.
8. A reduction furnace nitrogen protection system according to claim 5, characterized in that: The control valve, the first valve, the second valve, the third valve, the fourth valve, the fifth valve and the sixth valve are all electrically connected to a control system. The control system regulates the opening and closing of the control valve according to the furnace pressure of the reduction furnace and the opening and closing states of the first valve, the second valve, the third valve, the fourth valve, the fifth valve and the sixth valve. When the furnace pressure is less than 5KPA and the first valve, the second valve, the third valve, the fourth valve, the fifth valve and the sixth valve are all closed, the control system regulates the control valve to open.