Collecting device for preventing combustion explosion of silicon powder

Abstract

The utility model relates to the technical field of polycrystalline silicon production, and discloses a collecting device for preventing combustion explosion of silicon powder, which comprises a silicon powder collecting barrel and a barrel cover covered above the silicon powder collecting barrel, a discharge pipe is arranged on the barrel cover, the other end of the discharge pipe is connected with a discharge port of a filter of dust removal equipment, and the discharge port of the filter is connected with the silicon powder collecting barrel. The silicon powder collecting barrel comprises an outer-layer barrel body and an inner-layer barrel body located in the outer-layer barrel body, a buffer cavity used for introducing protective gas is formed between the outer-layer barrel body and the inner-layer barrel body, an inner cavity in the middle of the inner-layer barrel body is a silicon powder collecting pool, and the buffer cavity is communicated with an inner cavity of the inner-layer barrel body; an air inlet communicated with the buffering cavity is formed in the position, close to the bottom of the barrel, of the barrel body of the outer-layer barrel body. According to the device, air in silicon powder discharged by front-end equipment is diluted and completely discharged in a gas replacement manner, and the introduced gas slowly overflows into the collecting tank after being decelerated and buffered and does not directly impact the silicon powder, so that the silicon powder can be effectively deposited in the device, and the phenomenon of dust cloud is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of polysilicon production, and particularly relates to a collecting device for preventing silicon powder from burning and exploding. Background Technique

[0002] Polysilicon is the basic material for manufacturing solar cell wafers for photovoltaic power generation. At the same time, single crystal silicon produced from electronic-grade polysilicon is the basic material for the electronic information industry and is the raw material for producing large-scale integrated circuits, semiconductor discrete components, and power electronic devices. At present, the mainstream technical route for polysilicon production is the improved Siemens method. During the production process of reducing high-purity silicon by the Siemens method, a large amount of silicon powder will accumulate on the bottom plate of the reduction furnace. The traditional method is to use a vacuum pump to suck the silicon powder on the bottom plate and then pass the adsorbed silicon powder into a collection barrel for collection. However, because the collected silicon powder contains a large amount of combustible gas and materials, it is extremely easy to burn in the barrel, and even flash explosions may occur.

[0003] The utility model patent with the publication number CN215388242U discloses a storage mechanism and a dust removal device. The storage mechanism includes: a tank body, a top cover, a discharge pipe, a protective gas pipe, and an exhaust pipe; when the storage mechanism is working, the protective gas flows along the protective gas pipe into the tank body, the air in the tank body is displaced, the air passes through the filter holes of the filtering component, and is discharged from the exhaust pipe of the top cover, while the silicon powder is intercepted by the filtering component and stays in the tank body. The air density in the tank body decreases, reducing the probability of contact between combustible components and air, and avoiding the combustion or flash explosion caused by the reaction of chlorosilane and air to generate high temperature.

[0004] During the process of introducing the protective gas in the above device, the gas directly enters the storage space of the tank body through the protective gas pipe, and the introduced gas directly acts on the combustible components such as silicon powder in the tank body. Due to the certain flow rate and pressure of the gas, it will cause a direct impact on the silicon powder, resulting in the dusting of the silicon powder in the tank body. The silicon powder cannot be effectively deposited in the tank body, and a dust cloud will appear in the tank body. Therefore, there is still a great possibility of flash explosion. Summary of the Invention

[0005] In order to solve the problems and deficiencies existing in the above-mentioned prior art, the utility model proposes a collecting device for preventing silicon powder from burning and exploding. During the process of collecting silicon powder, nitrogen is slowly introduced into this device to discharge the air in the device, so that the silicon powder collected in the device is isolated from the outside air and can be effectively deposited in the device, effectively avoiding the burning and explosion of the collected silicon powder during the operation process.

[0006] In order to achieve the above-mentioned invention purpose, the technical solution of the utility model is specifically as follows:

[0007] The utility model provides a collection device for preventing the combustion and explosion of silicon powder. The device includes a silicon powder collection barrel and a barrel cover covering the upper part of the silicon powder collection barrel. A discharge pipe is arranged on the barrel cover, and the other end of the discharge pipe is connected to the discharge port of the filter of the dust removal equipment. The silicon powder collection barrel includes an outer barrel body and an inner barrel body located inside the outer barrel body. A buffer cavity for introducing a protective gas is provided between the outer barrel body and the inner barrel body. The inner cavity in the middle of the inner barrel body is a silicon powder collection pool, and the buffer cavity is communicated with the inner cavity of the inner barrel body. An air inlet communicated with the buffer cavity is arranged near the bottom of the barrel body of the outer barrel body.

[0008] Preferably, a pressure relief port is arranged on the barrel cover.

[0009] Preferably, a double-stage discharge valve is arranged on the discharge pipe.

[0010] Preferably, a check valve is arranged at the pressure relief port.

[0011] Preferably, the silicon powder collection barrel and the barrel cover are hermetically connected through a connecting flange.

[0012] Preferably, the discharge pipe is welded and fixed on the barrel cover.

[0013] The beneficial effects of the utility model are as follows:

[0014] 1. The utility model designs the container for collecting and storing silicon powder as a sandwich structure. The sandwich of the collection container is a gas buffer chamber. The protective gas introduced into the container slowly enters the silicon powder collection pool in the container after being buffered and decelerated in the buffer chamber, diluting and exhausting all the air in the whole container. The silicon powder collected in the device is isolated from the external air, and since the introduced gas slowly overflows into the collection pool after being decelerated and buffered, it will not directly impact the silicon powder. Therefore, the silicon powder can be effectively deposited in the device, avoiding the phenomenon of dust cloud. In summary, this device can effectively prevent the combustion and explosion of the collected silicon powder during the operation process, providing a reliable safety guarantee for the continuous and stable operation of the production device.

[0015] 2. A double-stage discharge valve is arranged on the discharge pipe of the utility model, which can ensure that the silicon powder discharged from the filter of the front-end dust removal equipment smoothly falls into the collection device.

[0016] 3. A pressure relief port is arranged on the barrel cover of the device of the utility model. The pressure relief port can prevent the collection device from being pressurized, and finally the device can continuously replace and exhaust gas. Description of the Drawings

[0017] The foregoing and following specific descriptions of the utility model become clearer when read in conjunction with the following drawings, in which:

[0018] Figure 1 is the structural diagram of the device of the utility model;

[0019] In the figure:

[0020] 1. Silicon powder collection barrel; 2. Barrel cover; 3. Discharge pipe; 4. Air inlet; 5. Pressure relief port; 6. Double-stage discharge valve; 101. Outer barrel body; 102. Inner barrel body; 103. Buffer chamber. Specific implementation mode

[0021] In order to enable those skilled in the art to better understand the technical solutions in the present utility model, the following will further illustrate the technical solutions for achieving the inventive purpose of the present utility model through several specific embodiments. It should be noted that the technical solutions claimed by the present utility model include but are not limited to the following embodiments. Based on the embodiments in the present utility model, all other embodiments obtained by those skilled in the art without making creative efforts shall fall within the protection scope of the present utility model.

[0022] Embodiment 1

[0023] This embodiment discloses a collection device for preventing the combustion and explosion of silicon powder. Referring to the attached drawings of the specification Figure 1 As shown, it is composed of a silicon powder collection barrel 1 and a barrel cover 2 hermetically covered above the silicon powder collection barrel 1. Among them, the silicon powder collection barrel 1 is a sandwich-type collection barrel. The collection barrel includes an outer barrel body 101 and an inner barrel body 102 arranged in the cavity of the outer barrel body 101. An annular sandwich cavity is formed between the barrel bodies of the two barrels, and this sandwich cavity is a buffer chamber 103 for introducing a protective gas. The buffer chamber 103 is communicated with the inner cavity of the inner barrel body 102. The inner cavity of the inner barrel body 102 is a silicon powder collection pool. An air inlet 4 communicated with the buffer chamber 103 is arranged on the barrel body of the outer barrel body 101. Further, a discharge pipe 3 is arranged on the barrel cover 2, and the other end of the discharge pipe 3 is connected to the discharge port of the filter of the front-end dust removal equipment. A pressure relief port 5 is arranged on the barrel cover 2.

[0024] In the implementation mode depicted in the present utility model, the bottom of the inner barrel body 102 is connected to the bottom of the outer barrel body 101, and the overall height of the inner barrel body 102 is less than that of the outer barrel body 101. In this way, after the barrel cover 102 is covered on the collection barrel, the protective gas moving upward from the buffer chamber 103 can enter the cavity of the barrel through the top opening of the inner barrel body 102, displacing the air carried in the silicon powder.

[0025] In the embodiment depicted by the present utility model, when the device is in use, first connect the air inlet 4 to an external gas source, and introduce a protective gas into the buffer chamber 103. The protective gas displaces the air inside the device through the pressure relief port 5. After continuously introducing the protective gas for a period of time to completely exhaust the air inside the device, connect the end of the discharge pipe 3 of the device to the discharge port of the filter of the front-end dust removal equipment; open the valve on the discharge pipe 103, and the silicon powder on the reduction furnace chassis filtered by the filter will be discharged into the inner cavity of the inner barrel 102 through the discharge pipe 103 for collection. During the above operation process, a continuous stream of protective gas passes through the air inlet 4, enters the device after decelerating and buffering through the buffer chamber 103, so that a small amount of air carried in the silicon powder discharged from the front-end equipment is diluted and discharged from the pressure relief port, and the silicon powder collected inside the device is isolated from the external air; moreover, based on the pressure relief port 5 provided on the bucket lid 2, the protective gas introduced into the device can also be discharged from the pressure relief port 5. The protective gas forms a one-in-one-out cycle inside the device to achieve cyclic replacement, and the device will not have a pressure buildup situation.

[0026] It can be understood that the protective gas is an inert gas, and nitrogen, helium, argon, etc. can be selected. However, considering the economic cost and the ease of obtaining, nitrogen is preferably selected.

[0027] It can be understood that the air inlet 4 is usually arranged at the lower part of the barrel body of the outer barrel 101, near the bottom of the barrel. In this way, it can play a good buffering role for the introduced protective gas, and after sufficient buffering, it overflows into the barrel cavity from the top opening of the inner barrel 102.

[0028] It can be understood that the tail (discharge port) of the discharge pipe 3 usually extends into the inner cavity of the inner barrel 102.

[0029] Embodiment 2

[0030] This embodiment discloses a collection device for preventing the combustion and explosion of silicon powder. On the basis of Embodiment 1, a one-way valve is provided at the pressure relief port 5. When in use, first open the one-way valve of the device, then connect the air inlet 4 of the device to an external gas source, and introduce a protective gas into the buffer chamber 103. The protective gas displaces the air inside the device through the pressure relief port 5. During the process of collecting silicon powder, the one-way valve is always in an open state. After the silicon powder is collected, close the one-way valve, which can prevent external air from flowing back into the inner barrel 102 from the pressure relief port.

[0031] Furthermore, in the embodiment depicted by the present utility model, a double-stage discharge valve 6 is provided on the discharge pipe 3. It can be understood that the double-stage discharge valve 6 refers to a structure composed of a first discharge valve and a second discharge valve sequentially arranged from top to bottom on the discharge pipe 3. When the device is in use, when the filter above the collection device discharges silicon powder, the upper first discharge valve is opened first, and the lower second discharge valve is closed. After about 10 - 20 seconds, the upper valve is closed and the lower valve is opened, forming a single discharge of silicon powder.

[0032] When the first discharge valve is opened and the second discharge valve is closed, the silicon powder will fall between the two valves due to gravity. When the first discharge valve is closed and the second discharge valve is opened, the silicon powder between the two valves will fall into the collection bucket. The above double-valve structure can ensure the normal discharge of silicon powder, without being affected by the negative pressure of the front-end dust collection equipment, and the double valves can also block the inhalation of external air.

[0033] Furthermore, the silicon powder collection bucket 1 and the bucket cover 2 are hermetically connected through a connecting flange. A first flange is provided at the top of the outer barrel body 101, a second flange is provided on the bucket cover, and an annular gasket is provided on the flange. After the two flanges are butted, they are fixedly connected through connecting bolts.

[0034] Furthermore, the discharge pipe 3 is fixedly welded to the bucket cover 2.

[0035] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present utility model 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 should not be construed as limiting the protection scope of the present utility model.

[0036] In the description of the present utility model, it should also be noted that unless otherwise clearly specified and defined, the terms "set", "installed", "connected" 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 directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0037] The above are only the preferred embodiments of the present utility model, and do not impose any formal restrictions on the present utility model. Any simple modifications and equivalent changes made to the above embodiments based on the technical essence of the present utility model all fall within the protection scope of the present utility model.

Claims

1. A collecting device for preventing the combustion and explosion of silicon powder, characterized in that, The device includes a silicon powder collection barrel (1) and a barrel cover (2) covering the upper part of the silicon powder collection barrel (1). A discharge pipe (3) is arranged on the barrel cover (2), and the other end of the discharge pipe (3) is connected to the discharge port of the dust removal equipment filter. The silicon powder collection barrel (1) includes an outer barrel body (101) and an inner barrel body (102) located inside the outer barrel body (101). A buffer chamber (103) for introducing a protective gas is provided between the outer barrel body (101) and the inner barrel body (102). The inner cavity of the inner barrel body (102) is a silicon powder collection pool, and the buffer chamber (103) is communicated with the inner cavity of the inner barrel body (102). An air inlet (4) communicated with the buffer chamber (103) is arranged on the barrel body of the outer barrel body (101) near the bottom of the barrel.

2. The collecting device for preventing combustion and explosion of silicon powder according to claim 1, characterized in that, A pressure relief port (5) is arranged on the barrel cover (2).

3. The collection device for preventing combustion and explosion of silicon powder according to claim 1, characterized in that, A double-stage discharge valve (6) is arranged on the discharge pipe (3).

4. The collecting device for preventing combustion and explosion of silicon powder according to claim 2, characterized in that, A one-way valve is arranged at the pressure relief port (5).

5. The collection device for preventing combustion and explosion of silicon powder according to claim 1, characterized in that, The silicon powder collection barrel (1) and the barrel cover (2) are hermetically connected through a connecting flange.

6. The collecting device for preventing combustion and explosion of silicon powder according to claim 1, wherein The discharge pipe (3) is fixedly welded on the barrel cover (2).

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