Polycrystalline silicon reduction feeding system
By connecting two sets of feeding systems and utilizing high-pressure hydrogen delivery and segmented heating control, the stability and continuity issues of the polysilicon production system were solved, system redundancy was achieved, production efficiency was improved, and costs were reduced.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-18
- Publication Date
- 2026-03-27
AI Technical Summary
In existing polysilicon production systems, the two independent material supply and distribution systems lack complementary functions, resulting in poor system stability and continuity, frequent shutdowns that increase costs and reduce production efficiency.
A polycrystalline silicon reduction feeding system is designed by connecting two parallel feeding systems, using high-pressure, high-purity hydrogen to transport trichlorosilane, and employing a segmented heating method combined with low-pressure and medium-pressure steam to precisely control the heating process, thereby achieving system redundancy and stable feeding.
It effectively reduced the number of downtimes caused by equipment failures, improved the stability and continuity of production, reduced equipment failure points, optimized energy utilization, improved production efficiency, and reduced costs.
Smart Images
Figure CN224046991U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the polycrystal silicon production field especially, and relates to a polycrystal silicon reduction feeding system. BACKGROUND
[0002] In the polycrystal silicon production process, the "improved Siemens method" is widely used. At present, the reduction furnace plant of this method is usually equipped with a set of independent feeding distribution system on both sides. Since the two sets of feeding distribution systems are independent of each other, when any equipment in the system fails or planned maintenance is required due to maintenance needs, the entire production system has to be stopped. Since the two sets of feeding systems do not realize the complementary function in the true sense, the stability and continuity of the polycrystal silicon production system are seriously affected. Frequent stoppage of the system not only increases the production cost, but also reduces the product quality and production efficiency. At the same time, after the system is stopped, a large amount of time and energy is consumed to restore the production conditions, further aggravating the waste of resources. SUMMARY
[0003] In order to solve the above problems, the purpose of the utility model is to provide a polycrystal silicon reduction feeding system, which can effectively reduce the risk of system shutdown, significantly improve the stability and continuity of the polycrystal silicon production process, and thus improve the production efficiency and reduce the production cost.
[0004] The utility model is implemented by the following technical solutions:
[0005] A polycrystal silicon reduction feeding system, comprising two sets of parallel feeding systems, each set of the feeding system comprising a trichlorosilane buffer tank, a vaporizer, a superheater, and multiple reduction furnaces, the liquid outlet of the trichlorosilane buffer tank being communicated with the liquid inlet of the vaporizer through a pipeline, the gas outlet of the vaporizer being communicated with the inlet of the superheater through a pipeline, the outlet of the superheater being divided into multiple paths and being communicated with the raw material inlets of the multiple reduction furnaces, respectively;
[0006] The steam outlet end of the low-pressure steam pipeline is divided into two paths and is communicated with the steam inlets of the two vaporizers of the two sets of feeding systems, respectively, and a low-pressure steam regulating valve is arranged at the steam inlet of the vaporizer; the steam outlet end of the medium-pressure steam pipeline is divided into two paths and is communicated with the steam inlets of the two superheaters of the two sets of feeding systems, respectively, and a medium-pressure steam regulating valve is arranged at the steam inlet of the superheater;
[0007] The liquid outlets of the two trichlorosilane buffer tanks of the two sets of feeding systems are communicated through a buffer tank communication pipeline, and a buffer tank communication valve is arranged on the buffer tank communication pipeline;
[0008] The gas outlets of the two vaporizers of the two sets of feeding systems are communicated through a vaporizer communication pipeline, and a vaporizer communication valve is arranged on the vaporizer communication pipeline;
[0009] The outlet of the two superheaters of the two sets of feed systems is communicated through a superheater communication pipeline, and a superheater communication valve is arranged on the superheater communication pipeline;
[0010] A cut-off valve is arranged at the liquid outlet of the trichlorosilane buffer tank, the gas outlet of the vaporizer and the outlet of the superheater.
[0011] Further, a hydrogen pipeline is further arranged, and the gas outlet end of the hydrogen pipeline is communicated with the gas inlets of the two trichlorosilane buffer tanks of the two sets of feed systems in two ways, and a hydrogen flow regulating valve is arranged at the gas inlet of the trichlorosilane buffer tank.
[0012] Further, a vent is arranged at the top of the trichlorosilane buffer tank, and a safety valve is arranged at the vent; a first pressure sensor is arranged in the trichlorosilane buffer tank, the signal output end of the first pressure sensor is signal connected with the signal input end of a controller, and the signal output end of the controller is signal connected with the signal input end of the safety valve.
[0013] Further, a second pressure sensor is arranged in the vaporizer, the signal output end of the second pressure sensor is signal connected with the signal input end of a controller, and the signal output end of the controller is signal connected with the signal input end of the low-pressure steam regulating valve.
[0014] Further, a temperature sensor is arranged in the superheater, the signal output end of the temperature sensor is signal connected with the signal input end of a controller, and the signal output end of the controller is signal connected with the signal input end of the medium-pressure steam regulating valve.
[0015] The utility model discloses the advantages of the utility model are as follows:
[0016] 1. by the parallel feed system of two sets of originally independent communication, when one set of feed system appears the fault or needs overhauling, can be switched to another feed system for the whole production line feed, realizes the material communication between two sides feed system, can ensure that production does not interrupt, effectively reduces the parking frequency caused by equipment failure, greatly improves the stability and continuity of production, realizes the redundancy function of system.
[0017] 2. using high-pressure high-purity hydrogen as the conveying power, liquid trichlorosilane is pressed into the vaporizer from the trichlorosilane buffer tank, avoids using mechanical pump, reduces the equipment failure point and pollution risk. Meanwhile, hydrogen is one of raw materials of reduction reaction, can preheat and mix part of hydrogen in the conveying process, is favorable for subsequent reaction.
[0018] 3. The vaporization and overheating stages adopt a sectional heating mode, and use steam of different pressure grades (low pressure and medium pressure), so that the heating process can be accurately controlled, the trichlorosilane can reach the optimal reaction state, the reduction efficiency is improved, the energy utilization is optimized, and the energy consumption is reduced. 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 to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.
[0020] Figure 1 It is a system connection schematic diagram of the embodiment.
[0021] Figure 2 It is a control principle diagram of the embodiment.
[0022] In the figure: feed system 1, trichlorosilane buffer tank 1.1, vaporizer 1.2, overheater 1.3, reduction furnace 1.4, low-pressure steam pipeline 2, medium-pressure steam pipeline 3, low-pressure steam regulating valve 4, medium-pressure steam regulating valve 5, buffer tank communication pipeline 6, buffer tank communication valve 7, vaporizer communication pipeline 8, vaporizer communication valve 9, overheater communication pipeline 10, overheater communication valve 11, cut-off valve 12, hydrogen pipeline 13, hydrogen flow regulating valve 14, safety valve 15, first pressure sensor 16, second pressure sensor 17, temperature sensor 18, controller 19. DETAILED DESCRIPTION
[0023] The technical solutions in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.
[0024] Embodiment 1
[0025] As Figure 1 , Figure 2The polycrystalline silicon reduction feed system shown in the embodiment comprises two sets of parallel feed systems 1, each of which comprises a trichlorosilane buffer tank 1.1, a vaporizer 1.2, a superheater 1.3 and multiple reduction furnaces 1.4, the liquid outlet of the trichlorosilane buffer tank 1.1 is communicated with the liquid inlet of the vaporizer 1.2 through a pipeline, the gas outlet of the vaporizer 1.2 is communicated with the inlet of the superheater 1.3 through a pipeline, and the outlet of the superheater 1.3 is divided into multiple paths and communicated with the raw material inlets of the multiple reduction furnaces 1.4, respectively.
[0026] The steam outlet end of the low-pressure steam pipeline 2 is divided into two paths and communicated with the steam inlets of the two vaporizers 1.2 of the two sets of feed systems 1, respectively, and a low-pressure steam regulating valve 4 is arranged at the steam inlet of the vaporizer 1.2; the steam outlet end of the medium-pressure steam pipeline 3 is divided into two paths and communicated with the steam inlets of the two superheaters 1.3 of the two sets of feed systems 1, respectively, and a medium-pressure steam regulating valve 5 is arranged at the steam inlet of the superheater 1.3.
[0027] The liquid outlets of the two trichlorosilane buffer tanks 1.1 of the two sets of feed systems 1 are communicated through a buffer tank communication pipeline 6, and a buffer tank communication valve 7 is arranged on the buffer tank communication pipeline 6; the gas outlets of the two vaporizers 1.2 of the two sets of feed systems 1 are communicated through a vaporizer communication pipeline 8, and a vaporizer communication valve 9 is arranged on the vaporizer communication pipeline 8; the outlets of the two superheaters 1.3 of the two sets of feed systems 1 are communicated through a superheater communication pipeline 10, and a superheater communication valve 11 is arranged on the superheater communication pipeline 10; a shut-off valve 12 is arranged at the liquid outlet of the trichlorosilane buffer tank 1.1, the gas outlet of the vaporizer 1.2 and the outlet of the superheater 1.3.
[0028] The embodiment comprises a hydrogen pipeline 13, the gas outlet end of the hydrogen pipeline 13 is divided into two paths and communicated with the gas inlets of the two trichlorosilane buffer tanks 1.1 of the two sets of feed systems 1, respectively, and a hydrogen flow regulating valve 14 is arranged at the gas inlet of the trichlorosilane buffer tank 1.1.
[0029] In the embodiment, in order to control the system in time and accurately according to the actual operation of the site, and to improve the stability of the system operation, an intelligent control process is further added, specifically: a vent is arranged on the top of the trichlorosilane buffer tank 1.1, and a safety valve 15 is arranged at the vent; a first pressure sensor 16 is arranged in the trichlorosilane buffer tank 1.1; a second pressure sensor 17 is arranged in the vaporizer 1.2; and a temperature sensor 18 is arranged in the superheater 1.3.
[0030] The signal output ends of the first pressure sensor 16, the second pressure sensor 17 and the temperature sensor 18 are signal connected with the signal input end of a controller 19, and the signal output end of the controller 19 is signal connected with the signal input ends of the safety valve 15, the low-pressure steam regulating valve 4 and the medium-pressure steam regulating valve 5, respectively.
[0031] Working description:
[0032] In this embodiment, the two originally independent parallel supply systems 1 are connected by setting the buffer tank communication valve 7, the vaporizer communication valve 9 and the superheater communication valve 11. When one of the supply systems 1 fails or needs to be repaired, the other supply system 1 can be quickly switched to supply the entire production line. Specifically, when the trichlorosilane buffer tank 1.1 of one of the supply systems 1 fails, first close the shut-off valve 12 at the outlet of the trichlorosilane buffer tank 1.1 to prevent material leakage; then open the buffer tank communication valve 7 on the buffer tank communication pipeline 6, so that the trichlorosilane buffer tank 1.1 of the other supply system 1 supplies the vaporizer 1.2 of the supply system 1 that has failed, i.e. the trichlorosilane buffer tank 1.1 of the other supply system 1 simultaneously supplies the vaporizers 1.2 of the two supply systems 1, realizing the communication of materials between the two supply systems 1, and ensuring uninterrupted production. When the vaporizer 1.2 or the superheater 1.3 of one of the supply systems 1 fails, the operation principle is the same as above. Through actual testing, the number of shutdowns due to equipment failure has been reduced by more than 80% after using the system of this embodiment, greatly improving the stability and continuity of production, and realizing the redundancy function of the system.
[0033] At the same time, in the production process, high-pressure high-purity hydrogen gas is used as the conveying power to press the liquid trichlorosilane from the trichlorosilane buffer tank 1.1 into the vaporizer 1.2. This conveying method avoids the use of mechanical pumps, reducing the number of equipment failure points and the risk of pollution. At the same time, hydrogen gas, as one of the raw materials for reduction reactions, can preheat and mix part of the hydrogen gas during the conveying process, which is beneficial to the subsequent reactions. By controlling the pressure in the trichlorosilane buffer tank 1.1, the conveying rate of trichlorosilane can be flexibly controlled to adapt to different production needs. Moreover, when the system is switched, the hydrogen gas pressure can be adjusted to balance the supply rates of the two supply systems 1, ensuring smooth transition.
[0034] In this embodiment, the pressure in the trichlorosilane buffer tank 1.1 can be monitored by the first pressure sensor 16, and when it exceeds the safety threshold, the safety valve 15 can be opened for protection. The pressure in the vaporizer 1.2 can be monitored by the second pressure sensor 17, and the amount of low-pressure steam entering the vaporizer 1.2 can be adjusted by adjusting the valve opening size of the low-pressure steam regulating valve 4, to prevent the vaporizer 1.2 from overpressure, and to ensure that the trichlorosilane in the vaporizer 1.2 is heated and vaporized into saturated vapor state trichlorosilane with a pressure of about 1.0 MPa(G) and a temperature of about 122℃. The temperature in the superheater 1.3 can be monitored by the temperature sensor 18, and the amount of medium-pressure steam entering the superheater 1.3 can be adjusted by adjusting the valve opening size of the medium-pressure steam regulating valve 5, to ensure that the saturated vapor state trichlorosilane in the superheater 1.3 is heated to about 133℃ of super-saturated gaseous trichlorosilane, and finally sent into the reduction furnace 1.4 for use.
[0035] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.
Claims
1. A polysilicon reduction feed system, comprising two sets of parallel feed systems, each set of the feed system comprising a trichlorosilane buffer tank, a vaporizer, a superheater and a plurality of reduction furnaces, the liquid outlet of the trichlorosilane buffer tank being communicated with the liquid inlet of the vaporizer through a pipeline, the gas outlet of the vaporizer being communicated with the inlet of the superheater through a pipeline, the outlet of the superheater being divided into a plurality of paths and communicated with the raw material inlets of the plurality of reduction furnaces respectively; characterized in that the steam outlet end of a low-pressure steam pipeline being divided into two paths and communicated with the steam inlets of the two vaporizers of the two sets of feed systems respectively, a low-pressure steam regulating valve being arranged at the steam inlet of the vaporizer; the steam outlet end of a medium-pressure steam pipeline being divided into two paths and communicated with the steam inlets of the two superheaters of the two sets of feed systems respectively, a medium-pressure steam regulating valve being arranged at the steam inlet of the superheater; the liquid outlets of the two trichlorosilane buffer tanks of the two sets of feed systems being communicated through a buffer tank communication pipeline, a buffer tank communication valve being arranged on the buffer tank communication pipeline; the gas outlets of the two vaporizers of the two sets of feed systems being communicated through a vaporizer communication pipeline, a vaporizer communication valve being arranged on the vaporizer communication pipeline; the outlets of the two superheaters of the two sets of feed systems being communicated through a superheater communication pipeline, a superheater communication valve being arranged on the superheater communication pipeline; a cut-off valve being arranged at the liquid outlet of the trichlorosilane buffer tank, the gas outlet of the vaporizer and the outlet of the superheater.
2. A polysilicon reduction feedstock system as claimed in claim 1, wherein, a hydrogen pipeline, the gas outlet end of the hydrogen pipeline being divided into two paths and communicated with the gas inlets of the two trichlorosilane buffer tanks of the two sets of feed systems respectively, a hydrogen flow regulating valve being arranged at the gas inlet of the trichlorosilane buffer tank.
3. A polysilicon reduction feedstock system as claimed in claim 1, wherein, a vent being arranged at the top of the trichlorosilane buffer tank, a safety valve being arranged at the vent; a first pressure sensor being arranged in the trichlorosilane buffer tank, the signal output end of the first pressure sensor being signal connected with the signal input end of a controller, the signal output end of the controller being signal connected with the signal input end of the safety valve.
4. A polysilicon reduction feedstock system as claimed in claim 1, wherein, a second pressure sensor being arranged in the vaporizer, the signal output end of the second pressure sensor being signal connected with the signal input end of a controller, the signal output end of the controller being signal connected with the signal input end of the low-pressure steam regulating valve.
5. A polysilicon reduction feedstock system as claimed in claim 1, wherein, a temperature sensor being arranged in the superheater, the signal output end of the temperature sensor being signal connected with the signal input end of a controller, the signal output end of the controller being signal connected with the signal input end of the medium-pressure steam regulating valve.