Polycrystalline silicon cold hydrogenation production system capable of maintaining heat exchanger without shutdown

Abstract

The utility model discloses a polycrystalline silicon cold hydrogenation production system capable of maintaining a heat exchanger without stopping, which comprises a fluidized bed reactor, a first-stage heat exchanger, a second-stage heat exchanger, a third-stage heat exchanger and a vaporizer, the fluidized bed reactor is connected with the first-stage heat exchanger, the first-stage heat exchanger is connected with the second-stage heat exchanger, and the third-stage heat exchanger is connected with the vaporizer. The second-stage heat exchanger is connected with a third-stage heat exchanger, the third-stage heat exchanger is connected with a vaporizer, and the third-stage heat exchanger is further connected with a dust remover. The polycrystalline silicon cold hydrogenation production system capable of overhauling the heat exchanger without stopping the machine is mainly used for cutting off and isolating the heat exchanger without influencing production after a second-stage or third-stage heat exchanger at an outlet of a fluidized bed reactor of a cold hydrogenation production device leaks, so that sufficient time is reserved for overhauling the heat exchanger, and the service life of the heat exchanger is prolonged. The heat exchanger can be merged into the system after being overhauled and qualified in replacement, and the leaked heat exchanger can be overhauled without long-time shutdown of the system.

Description

Technical Field

[0001] The utility model relates to the field of polysilicon cold hydrogenation production, in particular to a polysilicon cold hydrogenation production system capable of overhauling a heat exchanger without stopping the machine. Background Art

[0002] The polysilicon cold hydrogenation production system is a supporting equipment for the production and processing of polysilicon. In the modified Siemens process for producing polysilicon products, the cold hydrogenation device fluidized bed reactor has gaseous materials entering the reactor including silicon tetrachloride and hydrogen. After the reaction in the fluidized bed reactor (the bed contains silicon powder and catalyst), the gaseous materials discharged from the top of the fluidized bed reactor include hydrogen, trichlorosilane, silicon tetrachloride, dichlorosilane and some high-boiling substances. The gaseous material entering the fluidized bed reactor is mixed with hydrogen and silicon tetrachloride pressurized by the compressor and gasified with 1.0Mpa saturated steam (the temperature after gasification is about 150℃). The gasified mixed gas first enters the shell side of the three-stage heat exchanger D (the temperature increases from 150℃ to 270-280℃), and then goes to the shell side of the secondary heat exchanger C after heat exchange (the temperature increases from 270℃ to 400-410℃), and finally goes to the shell side of the primary heat exchanger B (the temperature increases from 410℃ to 500-510℃). The outlet of the primary heat exchanger B is heated by the electric heater E (the temperature entering the reactor is about 560-570℃) and enters the fluidized bed reactor. A; The operating pressure of fluidized bed reactor A is 2.8-3.2MpaG, and the temperature is 530-560℃; the gas phase after the reaction comes out from the top of fluidized bed reactor A, first enters the first-stage heat exchanger B tube side (the temperature is reduced from 550℃ to 450-460℃), then enters the second-stage heat exchanger C tube side (the temperature is reduced from 450℃ to 310-320℃), and finally enters the third-stage heat exchanger D tube side (the temperature is reduced from 300℃ to 220-230℃) before entering the next stage of dust removal and distillation process. With the continuous development of science and technology, people have higher and higher requirements for the manufacturing process of polysilicon cold hydrogenation production system.

[0003] The existing polysilicon cold hydrogenation production system has certain drawbacks when in use. Due to the uniqueness of polysilicon cold hydrogenation production, the temperature and pressure of the material streams entering and leaving the fluidized bed reactor are very high, and the requirements for the heat exchanger are also very high. In the production process of many companies in the industry, the secondary or tertiary heat exchangers have experienced multiple leakage production problems, resulting in the entire system being unable to operate and requiring shutdown for maintenance. Since the materials in the heat exchanger and pipeline are flammable and explosive substances, the cooling, replacement, and material withdrawal operations are very time-consuming, which is not conducive to the long-term production of the device. For this reason, we propose a polysilicon cold hydrogenation production system that can be used without stopping the heat exchanger for maintenance. Utility Model Content

[0004] Technical problem solved: In view of the deficiencies in the prior art, the utility model provides a polysilicon cold hydrogenation production system in which the heat exchanger can be repaired without stopping the system. It is mainly aimed at the leakage of the secondary or tertiary heat exchanger at the outlet of the fluidized bed reactor of the cold hydrogenation production device. The heat exchanger can be cut off and isolated without affecting production, leaving sufficient time for the maintenance of the heat exchanger. The heat exchanger can be integrated into the system after the maintenance is completed and the replacement is qualified. The system does not need to be stopped for a long time to repair the leaking heat exchanger, which can effectively solve the problems in the background technology.

[0005] Technical solution: To achieve the above-mentioned purpose, the technical solution adopted by the utility model is: a polysilicon cold hydrogenation production system that can maintain the heat exchanger without stopping the machine, including a fluidized bed reactor, a primary heat exchanger, a secondary heat exchanger, a tertiary heat exchanger and a vaporizer, the fluidized bed reactor is connected to the primary heat exchanger, the primary heat exchanger is connected to the secondary heat exchanger, the secondary heat exchanger is connected to the tertiary heat exchanger, the tertiary heat exchanger is connected to the vaporizer, and the tertiary heat exchanger is also connected to a dust collector, and an electric heater is connected between the fluidized bed reactor and the primary heat exchanger.

[0006] Preferably, the dust collector is connected to a distillation system, and the vaporizer is connected to a steam box and a hydrogen-silicon tetroxide mixing box.

[0007] Preferably, a first monitoring probe is installed on the first-stage heat exchanger, a second monitoring probe is installed on the second-stage heat exchanger, and a third monitoring probe is installed on the third-stage heat exchanger. The first monitoring probe, the second monitoring probe and the third monitoring probe are all connected to a monitoring controller.

[0008] Preferably, the output end of the dust collector is connected to the input end of the distillation system, and the output ends of the steam box and the hydrogen-silicon tetroxide mixing box are connected to the input end of the vaporizer.

[0009] Preferably, the first-stage heat exchanger is fixed to the first monitoring probe, the second-stage heat exchanger is fixed to the second monitoring probe, and the third-stage heat exchanger is fixed to the third monitoring probe, and the output ends of the first monitoring probe, the second monitoring probe and the third monitoring probe are electrically connected to the monitoring controller.

[0010] Preferably, the output end of the fluidized bed reactor is connected to the input end of the first-stage heat exchanger, and the input end of the fluidized bed reactor is connected to the output end of the first-stage heat exchanger through an electric heater. The first-stage heat exchanger, the second-stage heat exchanger and the third-stage heat exchanger are circularly connected, and seventeen groups of valves are installed between the first-stage heat exchanger, the second-stage heat exchanger and the third-stage heat exchanger.

[0011] Beneficial effects: Compared with the prior art, the utility model provides a polysilicon cold hydrogenation production system with a heat exchanger that can be repaired without stopping, which has the following beneficial effects: the polysilicon cold hydrogenation production system with a heat exchanger that can be repaired without stopping is mainly aimed at cutting off and isolating the secondary or tertiary heat exchanger at the outlet of the fluidized bed reactor of the cold hydrogenation production device after leakage, without affecting production, leaving sufficient time for the maintenance of the heat exchanger, and the heat exchanger can be incorporated into the system after the maintenance is completed and the replacement is qualified, and the system does not need to be stopped for a long time to repair the leaking heat exchanger;

[0012] When the heat exchanger leaks, the large system can continue to operate stably without stopping, ensuring the stability of the system;

[0013] Compared with the large system shutdown to repair the leaking heat exchanger, manually cutting off the leaking heat exchanger can maintain normal production, which improves the safety of system operation;

[0014] The removed heat exchanger is replaced and repaired. The repair time is not urgent. After the repair is completed, the heat exchanger can be put into use again, which ensures the economic efficiency of the device operation. The entire polysilicon cold hydrogenation production system has a simple structure, is easy to operate, and has a better effect than the traditional method. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The utility model is a schematic diagram of the overall structure of a polysilicon cold hydrogenation production system capable of non-stop maintenance of a heat exchanger.

[0016] Figure 2 The utility model is a schematic diagram of the structure of three groups of heat exchangers in a polysilicon cold hydrogenation production system in which the heat exchanger can be repaired without stopping.

[0017] Figure 3 The utility model is a structural schematic diagram of a vaporizer in a polysilicon cold hydrogenation production system in which a heat exchanger can be repaired without stopping.

[0018] Figure 4 The utility model is a structural schematic diagram of a fluidized bed reactor in a polysilicon cold hydrogenation production system in which a heat exchanger can be repaired without stopping.

[0019] In the figure: 1. fluidized bed reactor; 2. electric heater; 3. distillation system; 4. dust collector; 5. hydrogen-silicon tetroxide mixing box; 6. vaporizer; 7. steam box; 8. three-stage heat exchanger; 9. monitoring controller; 10. two-stage heat exchanger; 11. one-stage heat exchanger; 12. second monitoring probe; 13. first monitoring probe; 14. third monitoring probe. DETAILED DESCRIPTION

[0020] The technical solution of the utility model will be clearly and completely described below in conjunction with the accompanying drawings and specific embodiments, but those skilled in the art will understand that the embodiments described below are part of the embodiments of the utility model, rather than all of the embodiments, and are only used to illustrate the utility model, and should not be considered as limiting the scope of the utility model. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the utility model. If the specific conditions are not specified in the embodiments, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0021] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying 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 limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0022] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" 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 or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0023] like Figure 1-4 As shown, a polysilicon cold hydrogenation production system in which the heat exchanger can be repaired without stopping the machine, comprises a fluidized bed reactor 1, a primary heat exchanger 11, a secondary heat exchanger 10, a tertiary heat exchanger 8 and a vaporizer 6, wherein the fluidized bed reactor 1 is connected to the primary heat exchanger 11, the primary heat exchanger 11 is connected to the secondary heat exchanger 10, the secondary heat exchanger 10 is connected to the tertiary heat exchanger 8, the tertiary heat exchanger 8 is connected to the vaporizer 6, and the tertiary heat exchanger 8 is also connected to a dust collector 4, and an electric heater 2 is connected between the fluidized bed reactor 1 and the primary heat exchanger 11. The system is mainly for cutting off and isolating the secondary or tertiary heat exchanger at the outlet of the fluidized bed reactor of the cold hydrogenation production device without affecting the production after the secondary or tertiary heat exchanger leaks, so as to leave sufficient time for the maintenance of the heat exchanger. After the heat exchanger is repaired and replaced and qualified, it can be incorporated into the system, and the system does not need to be stopped for a long time to repair the leaking heat exchanger.

[0024] Furthermore, the dust collector 4 is connected to the distillation system 3 , and the vaporizer 6 is connected to the steam box 7 and the hydrogen-silicon tetroxide mixing box 5 .

[0025] Furthermore, a first monitoring probe 13 is installed on the first-stage heat exchanger 11, a second monitoring probe 12 is installed on the second-stage heat exchanger 10, and a third monitoring probe 14 is installed on the third-stage heat exchanger 8. The first monitoring probe 13, the second monitoring probe 12 and the third monitoring probe 14 are all connected to a monitoring controller 9.

[0026] Furthermore, the output end of the dust collector 4 is connected to the input end of the distillation system 3 , and the output ends of the steam box 7 and the hydrogen-silicon tetroxide mixing box 5 are connected to the input end of the vaporizer 6 .

[0027] Furthermore, the first-stage heat exchanger 11 is fixed to the first monitoring probe 13, the second-stage heat exchanger 10 is fixed to the second monitoring probe 12, the third-stage heat exchanger 8 is fixed to the third monitoring probe 14, and the output ends of the first monitoring probe 13, the second monitoring probe 12 and the third monitoring probe 14 are electrically connected to the monitoring controller 9.

[0028] Furthermore, the output end of the fluidized bed reactor 1 is connected to the input end of the first-stage heat exchanger 11, and the input end of the fluidized bed reactor 1 is connected to the output end of the first-stage heat exchanger 11 through the electric heater 2. The first-stage heat exchanger 11, the second-stage heat exchanger 10 and the third-stage heat exchanger 8 are circularly connected, and seventeen groups of valves are installed between the first-stage heat exchanger 11, the second-stage heat exchanger 10 and the third-stage heat exchanger 8.

[0029] Working principle: The utility model includes a fluidized bed reactor 1, an electric heater 2, a distillation system 3, a dust collector 4, a hydrogen-silicon tetroxide mixing box 5, a vaporizer 6, a steam box 7, a three-stage heat exchanger 8, a monitoring controller 9, a two-stage heat exchanger 10, a one-stage heat exchanger 11, a second monitoring probe 12, a first monitoring probe 13, and a third monitoring probe 14. It is mainly used for cutting off and isolating the two-stage or three-stage heat exchanger at the outlet of the fluidized bed reactor of a cold hydrogenation production device without affecting production after the leakage of the heat exchanger, leaving sufficient time for the maintenance of the heat exchanger. The heat exchanger can be incorporated into the system after the maintenance is completed and the replacement is qualified, and the system does not need to be stopped for a long time to repair the leaking heat exchanger.

[0030] When the heat exchanger leaks, the large system can continue to operate stably without stopping, ensuring the stability of the system;

[0031] Compared with the large system shutdown to repair the leaking heat exchanger, manually cutting off the leaking heat exchanger can maintain normal production, which improves the safety of system operation;

[0032] The removed heat exchanger can be replaced and repaired. The time for repair is not urgent. After the repair is completed, the heat exchanger can be put into use again, which ensures the economical operation of the device.

[0033] It should be noted that, in this article, relational terms such as first and second (number one, number two), etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "including one..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0034] The above shows and describes the basic principle and main features of the utility model and the advantages of the utility model. The technicians in this industry should understand that the utility model is not limited by the above embodiments, and the above embodiments and descriptions are only for explaining the principle of the utility model. Without departing from the spirit and scope of the utility model, the utility model will have various changes and improvements, and these changes and improvements fall within the scope of the utility model to be protected.

Claims

1. A polysilicon cold hydrogenation production system capable of non-stop maintenance of heat exchangers, comprising a fluidized bed reactor (1), a primary heat exchanger (11), a secondary heat exchanger (10), a tertiary heat exchanger (8) and a vaporizer (6), characterized in that: The fluidized bed reactor (1) is connected to a primary heat exchanger (11), the primary heat exchanger (11) is connected to a secondary heat exchanger (10), the secondary heat exchanger (10) is connected to a tertiary heat exchanger (8), the tertiary heat exchanger (8) is connected to a vaporizer (6), and the tertiary heat exchanger (8) is also connected to a dust collector (4), and an electric heater (2) is connected between the fluidized bed reactor (1) and the primary heat exchanger (11).

2. The polysilicon cold hydrogenation production system with heat exchanger that can be repaired without stopping according to claim 1 is characterized in that: The dust collector (4) is connected to a distillation system (3), and the vaporizer (6) is connected to a steam box (7) and a hydrogen-silicon tetroxide mixing box (5).

3. The polysilicon cold hydrogenation production system with heat exchanger that can be repaired without stopping according to claim 1 is characterized in that: The first-stage heat exchanger (11) is installed with a first monitoring probe (13), the second-stage heat exchanger (10) is installed with a second monitoring probe (12), and the third-stage heat exchanger (8) is installed with a third monitoring probe (14); the first monitoring probe (13), the second monitoring probe (12), and the third monitoring probe (14) are all connected to a monitoring controller (9).

4. The polysilicon cold hydrogenation production system with heat exchanger that can be repaired without stopping according to claim 2 is characterized in that: The output end of the dust collector (4) is connected to the input end of the distillation system (3), and the output ends of the steam box (7) and the hydrogen-silicon tetroxide mixing box (5) are connected to the input end of the vaporizer (6).

5. The polysilicon cold hydrogenation production system with heat exchanger that can be repaired without stopping according to claim 3 is characterized in that: The first-stage heat exchanger (11) is fixed to the first monitoring probe (13), the second-stage heat exchanger (10) is fixed to the second monitoring probe (12), and the third-stage heat exchanger (8) is fixed to the third monitoring probe (14), and the output ends of the first monitoring probe (13), the second monitoring probe (12), and the third monitoring probe (14) are electrically connected to the monitoring controller (9).

6. The polysilicon cold hydrogenation production system with heat exchanger that can be repaired without stopping according to claim 1, characterized in that: The output end of the fluidized bed reactor (1) is connected to the input end of the first-stage heat exchanger (11); the input end of the fluidized bed reactor (1) is connected to the output end of the first-stage heat exchanger (11) via an electric heater (2); the first-stage heat exchanger (11), the second-stage heat exchanger (10) and the third-stage heat exchanger (8) are connected in a loop; and seventeen sets of valves are installed between the first-stage heat exchanger (11), the second-stage heat exchanger (10) and the third-stage heat exchanger (8).

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