Dehydrating device and trichlorosilane production system

Abstract

The embodiment of the application provides a dehydration device and a trichlorosilane production system, and relates to the technical field of trichlorosilane production. The dehydration device comprises a gas supply pipeline, a buffer assembly, a washing tower and a compressor. The gas supply pipeline comprises a first inlet and a first outlet, and the first inlet is used for being connected with a hydrogen chloride gas source. The buffer assembly comprises a first gas inlet, a second gas inlet and a second gas outlet, the first gas inlet is connected with the first outlet, and the second gas outlet is used for being connected with a trichlorosilane synthesis device. The washing tower comprises a second inlet and a second outlet, the second inlet is connected with the gas supply pipeline through a first pipeline, and a chlorosilane cold liquid spraying device is arranged in the washing tower. The compressor comprises a third inlet and a third outlet, the third inlet is connected with the second outlet, and the third outlet is connected with the second gas inlet through a second pipeline. The embodiment of the application does not need to newly add an independent device for dehydrating hydrogen chloride gas, so that the equipment investment cost and space occupation are effectively reduced.

Description

Technical Field

[0001] This application relates to the field of trichlorosilane production technology, and in particular to a dehydration device and a trichlorosilane production system. Background Technology

[0002] In the polysilicon production industry, hydrogen chloride gas is a key raw material for the synthesis of trichlorosilane. In this process, chlorine and hydrogen are burned at high temperature in a hydrogen chloride synthesis furnace to generate hydrogen chloride gas, which is then passed into a trichlorosilane synthesis furnace to react with silicon powder to produce trichlorosilane.

[0003] However, the hydrogen chloride gas at the outlet of the synthesis furnace has a high water content. When this hydrogen chloride gas with high water content comes into contact with trichlorosilane, the water will undergo a hydrolysis reaction with the chlorosilane to generate silica deposits. These deposits will adhere to the silicon powder feeding pipeline, which can easily clog the silicon powder feeding pipeline of the synthesis furnace and affect the normal operation of the reactor.

[0004] In related technologies, a dehydration device is added to the outlet of the hydrogen chloride synthesis furnace, but such devices occupy a large amount of plant space and increase equipment investment costs. Utility Model Content

[0005] This application provides a dehydration device and a trichlorosilane production system, which reduces the space occupied and investment cost of the dehydration device.

[0006] On the one hand, this application provides a dehydration device, comprising:

[0007] A gas supply pipeline, the gas supply pipeline including a first inlet and a first outlet, the first inlet being used to connect to a hydrogen chloride gas source;

[0008] A buffer assembly, comprising a first air inlet, a second air inlet, and a second air outlet, wherein the first air inlet is connected to the first air outlet, and the second air outlet is used to connect to a trichlorosilane synthesis device.

[0009] A scrubbing tower, comprising a second inlet and a second outlet, wherein the second inlet is connected to the gas supply pipeline via a first pipeline, and the scrubbing tower is equipped with a chlorosilane cold liquid spraying device;

[0010] The compressor includes a third inlet and a third outlet, the third inlet being connected to the second outlet, and the third outlet being connected to the second air inlet via a second pipe.

[0011] In some embodiments, the buffer component includes:

[0012] A first buffer tank, the first buffer tank including a first air inlet and a first air outlet;

[0013] The second buffer tank includes a second air inlet, a second air outlet, and a third air inlet;

[0014] The third pipe has one end connected to the first air outlet and the other end connected to the third air inlet.

[0015] In some embodiments, the first pipe and the third pipe are connected by a tee structure so that the gas supply pipe is connected to the scrubbing tower;

[0016] One end of the three-way structure is connected to the third pipe, and the other end is connected to the second pipe. The three-way structure is used to divert hydrogen chloride gas to the scrubbing tower.

[0017] In some embodiments, the tee structure includes a tee connector, the tee connector including a first end, a second end and a third end, the first end and the second end being connected to the third pipe, and the third end being connected to the second pipe.

[0018] In some embodiments, the tee structure further includes a figure-eight blind flange, which is disposed on the third pipe and located between the tee joint and the second buffer tank;

[0019] The figure-eight blind flange is configured to prevent the hydrogen chloride gas from flowing from the first buffer tank to the second buffer tank.

[0020] In some embodiments, the dehydration device further includes a condensation device, the condensation device including a fourth inlet and a fourth outlet, the fourth inlet being connected to the second outlet and the fourth outlet being connected to the third inlet.

[0021] In some embodiments, the scrubbing tower includes a packing element that is detachably disposed within the scrubbing tower.

[0022] In some embodiments, the inner wall of the scrubbing tower is provided with a protective layer, which is a polytetrafluoroethylene layer or a titanium alloy layer.

[0023] On the other hand, this application provides a trichlorosilane production system, comprising:

[0024] The above-mentioned dehydration device;

[0025] A hydrogen chloride synthesis apparatus, wherein the hydrogen chloride synthesis apparatus has a first discharge port, the first discharge port being connected to the first inlet of the gas supply pipeline;

[0026] The trichlorosilane synthesis apparatus includes a hydrogen chloride inlet, a silicon powder inlet, and a second discharge outlet. The hydrogen chloride inlet is connected to the second gas outlet, and the second discharge outlet is connected to the inlet of the scrubbing tower.

[0027] A synthesis liquid storage tank, the inlet of which is connected to the outlet of the feed inlet of the washing tower.

[0028] In some embodiments, the trichlorosilane production system further includes a separation component, which includes a cyclone separator and a syngas filter;

[0029] The trichlorosilane synthesis unit, the cyclone separator, the synthesis gas filter, and the scrubbing tower are connected in sequence;

[0030] The cyclone separator is used to separate the product gas from the mixed gas discharged from the trichlorosilane synthesis unit;

[0031] The synthesis gas filter is used to separate silicon powder from the product gas.

[0032] This application provides a dehydration device and a trichlorosilane production system. By connecting the gas supply pipeline, buffer assembly, and scrubbing tower, the chlorosilane liquid sprayed from the chlorosilane cold liquid spraying device in the scrubbing tower can be used as the dehydration medium, eliminating the need for additional independent equipment such as a concentrated sulfuric acid drying tower, thereby effectively reducing equipment investment costs and space occupation. Furthermore, this application connects the buffer assembly to the scrubbing tower via a first pipeline, allowing the hydrogen chloride gas dehydration function to operate in conjunction with the trichlorosilane synthesis system. This helps reduce the increased system complexity caused by the independent operation of the dehydration device in related technologies, thereby improving the processing efficiency and resource utilization of process gases. Attached Figure Description

[0033] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0034] Figure 1 This is a schematic diagram of the trichlorosilane production system provided in the embodiments of this application;

[0035] Figure 2 This is a schematic diagram of the tee connector in the embodiments of this application.

[0036] Figure label:

[0037] 10 - First pipe; 20 - Second pipe; 30 - Third pipe;

[0038] 100 - Gas supply pipeline; 110 - First inlet; 120 - First outlet;

[0039] 200 - Buffer assembly; 210 - First buffer tank; 211 - First air inlet; 212 - First air outlet; 220 - Second buffer tank; 221 - Second air inlet; 222 - Second air outlet; 223 - Third air inlet; 230 - T-connector; 231 - First end; 232 - Second end; 233 - Third end; 240 - Figure-eight blind flange;

[0040] 300 - Scrubber; 310 - Second inlet; 320 - Second outlet; 330 - Liquid outlet;

[0041] 400 - Compressor; 410 - Third inlet; 420 - Third outlet;

[0042] 500 - Condensation unit; 510 - Fourth inlet; 520 - Fourth outlet;

[0043] 600 - Hydrogen chloride synthesis unit; 610 - First discharge port;

[0044] 700 - Trichlorosilane synthesis unit; 710 - Hydrogen chloride inlet; 720 - Silicon powder inlet; 730 - Second discharge outlet;

[0045] 800 - Separation assembly; 810 - Cyclone separator; 820 - Syngas filter;

[0046] 900 - Synthetic liquid storage tank; 910 - Liquid inlet.

[0047] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0048] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0049] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a particular order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented, for example, in a sequence other than those illustrated or described herein.

[0050] In this application, the terms "exemplary" or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary" or "for example" in this application should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of terms such as "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0051] In the polysilicon production industry, hydrogen chloride gas is a key raw material for the synthesis of trichlorosilane. In this process, chlorine and hydrogen are burned at high temperature in a hydrogen chloride synthesis furnace to generate hydrogen chloride gas, which is then passed into a trichlorosilane synthesis furnace to react with silicon powder to produce trichlorosilane. However, the water content in the hydrogen chloride gas exiting the synthesis furnace is relatively high.

[0052] When hydrogen chloride gas with high moisture content comes into contact with trichlorosilane, the moisture reacts with the chlorosilane to form silica deposits. These deposits adhere to the silicon powder feeding pipeline, the inner wall of the reactor, and the separation equipment, causing pipeline blockage, reduced reaction efficiency, and even equipment shutdown for maintenance.

[0053] In related technologies, hydrogen dehydration devices are used to solve the above problems. For example, a concentrated sulfuric acid drying tower is used for hydrogen dehydration. However, this device not only occupies a lot of plant space, but also requires regular replacement of the dehydrating agent (concentrated sulfuric acid), which increases the equipment investment cost and operation and maintenance cost.

[0054] Based on this, this application provides a dehydration device and a trichlorosilane production system, aiming to solve the above-mentioned technical problems.

[0055] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0056] Firstly, please refer to Figure 1 and Figure 2 This application provides a dehydration device that can be applied to a trichlorosilane production system. The dehydration device includes an air supply pipeline 100, a buffer assembly 200, a washing tower 300, and a compressor 400.

[0057] The gas supply pipeline 100 includes a first inlet 110 and a first outlet 120, the first inlet 110 being used to connect to a hydrogen chloride gas source.

[0058] The gas supply pipeline 100 is a pipeline used to transport hydrogen chloride gas and can be made of corrosion-resistant metals or non-metallic materials, such as stainless steel or fluoroplastics. The first inlet 110 can be used to receive hydrogen chloride gas produced by the hydrogen chloride synthesis unit 600, and the first outlet 120 is connected to the first gas inlet 211 of the buffer assembly 200 to ensure that hydrogen chloride gas can be delivered to the buffer assembly 200 to provide a continuous gas source for subsequent processing stages.

[0059] The hydrogen chloride gas source can be a hydrogen chloride synthesis unit 600, which can be a hydrogen chloride synthesis furnace or a hydrogen chloride storage tank purchased directly from outside.

[0060] The second outlet 222 of the buffer assembly 200 is connected to the trichlorosilane synthesis device 700 and is used to deliver hydrogen chloride gas to the trichlorosilane synthesis device 700 to participate in the reaction.

[0061] The buffer assembly 200 includes a first air inlet 211, a second air inlet 221, and a second air outlet 222. The first air inlet 211 is connected to the first outlet 120, and the second air outlet 222 is used to connect to the trichlorosilane synthesis device 700.

[0062] The buffer assembly 200 serves as a component for gas pressure stabilization and flow transition. The first air inlet 211 is connected to the first outlet 120 of the gas supply pipeline 100. It is used to receive hydrogen chloride gas delivered from the gas supply pipeline 100 and can perform preliminary pressure stabilization on the hydrogen chloride gas, thereby controlling the gas pressure and preventing hydrogen chloride gas from directly entering the subsequent equipment due to pressure fluctuations, which would affect the processing effect.

[0063] The scrubbing tower 300 includes a second inlet 310 and a second outlet 320. The second inlet 310 is connected to the gas supply pipeline 100 through a first pipeline 10. Through the first pipeline 10, some or all of the hydrogen chloride gas in the gas supply pipeline 100 can be introduced into the scrubbing tower 300, so that the scrubbing tower 300 can remove the moisture in the hydrogen chloride gas and reduce the water content of the hydrogen chloride gas.

[0064] The scrubbing tower 300 is equipped with a chlorosilane cold liquid spraying device (not shown in the figure).

[0065] When the scrubbing tower 300 is operating, chlorosilane coolant can be evenly sprayed down from the top of the scrubbing tower 300 through a chlorosilane coolant spray device. At the same time, the mixed gas discharged from the trichlorosilane synthesis unit 700 (mainly composed of hydrogen chloride and trichlorosilane, with a small amount of silicon tetrachloride and hydrogen) enters from the bottom of the scrubbing tower 300, and the gas and liquid phases form sufficient counter-current contact inside the scrubbing tower 300. During this process, the trichlorosilane and silicon tetrachloride in the mixed gas are liquefied due to contact with the coolant and are eventually discharged from the bottom of the tower to the synthesis liquid storage tank 900 for recovery, while the non-condensable gases (mainly hydrogen chloride and hydrogen) are discharged from the top of the tower.

[0066] Furthermore, when the hydrogen chloride gas introduced from the gas supply pipeline 100 enters the scrubbing tower 300, the moisture it contains will preferentially undergo a hydrolysis reaction with the sprayed chlorosilane coolant to generate solid silica and hydrogen chloride. The moisture is selectively removed, while the hydrogen chloride gas, which does not participate in the hydrolysis reaction, remains in the gas phase. This achieves dehydration of the hydrogen chloride gas with high water content, thereby effectively reducing the water content of the hydrogen chloride gas.

[0067] The compressor 400 includes a third inlet 410 and a third outlet 420. The third inlet 410 is connected to the second outlet 320, and the third outlet 420 is connected to the second air inlet 221 through the second pipe 20.

[0068] The compressor 400 can pressurize the dehydrated hydrogen chloride gas, raising the gas pressure to a range that matches the feed pressure of the trichlorosilane synthesis unit 700. The pressurized dry hydrogen chloride gas is transported through the second pipeline 20 to the second inlet 221 of the buffer assembly 200. After being stabilized again by the buffer assembly 200, it is finally stably transported from the second outlet 222 to the trichlorosilane synthesis unit 700 to participate in the reaction.

[0069] In this embodiment, by connecting the gas supply pipeline 100, the buffer tank and the scrubbing tower 300, the chlorosilane liquid sprayed by the chlorosilane cold liquid spraying device in the scrubbing tower 300 can be used as the dehydration medium, without the need for additional independent equipment such as concentrated sulfuric acid drying tower, thereby effectively reducing equipment investment and space occupation.

[0070] Furthermore, within the scrubbing tower 300, chlorosilane liquid and hydrogen chloride gas come into counter-current contact. Moisture preferentially undergoes hydrolysis with the chlorosilane to generate silica and hydrogen chloride, achieving selective dehydration. This chemical reaction avoids the introduction of highly corrosive chemicals such as concentrated sulfuric acid, reducing equipment corrosion and improving system safety.

[0071] Meanwhile, in this embodiment, the buffer component 200 is connected to the scrubbing tower 300 through the first pipeline 10, so that the hydrogen chloride gas dehydration function can be operated in conjunction with the trichlorosilane synthesis system. This helps to reduce the increased system complexity caused by the independent operation of the dehydration device in related technologies, thereby improving the processing efficiency and resource utilization of process gases.

[0072] Therefore, the embodiments of this application solve the problems of high cost, high maintenance complexity and resource waste caused by the reliance on independent dehydration devices for hydrogen chloride dehydration in the prior art through the coordinated operation of the gas supply pipeline 100, the first pipeline 10, the scrubbing tower 300, the compressor 400 and the buffer assembly 200, which helps to achieve high efficiency, economy and sustainability of hydrogen chloride gas dehydration.

[0073] In some embodiments, the buffer assembly 200 includes a first buffer tank 210, a second buffer tank 220, and a third pipe 30, wherein the third pipe 30 is connected between the first buffer tank 210 and the second buffer tank 220.

[0074] The first buffer tank 210 includes a first air inlet 211 and a first air outlet 212; the second buffer tank 220 includes a second air inlet 221, a second air outlet 222 and a third air inlet 223; one end of the third pipe 30 is connected to the first air outlet 212 and the other end is connected to the third air inlet 223.

[0075] The first buffer tank 210 can perform preliminary pressure stabilization on the hydrogen chloride gas output from the hydrogen chloride synthesis unit 600. Its first inlet 211 is directly connected to the first outlet 120 of the gas supply pipeline 100. It can receive the supplied hydrogen chloride gas and reduce the pressure fluctuation during the process of transporting hydrogen chloride from the hydrogen chloride synthesis unit 600 to the first buffer tank 210 by utilizing the volume buffering effect of the internal cavity.

[0076] The second inlet 221 of the second buffer tank 220 is connected to the third outlet 420 of the compressor 400 via the second pipe 20, and can receive dry hydrogen chloride gas after dehydration and pressurization. The third inlet 223 is connected to the first outlet 212 of the first buffer tank 210 via the third pipe 30, and can introduce hydrogen chloride gas that has not undergone dehydration treatment. The two gases are uniformly mixed in the internal cavity of the second buffer tank 220.

[0077] Furthermore, the second buffer tank 220 can receive hydrogen chloride gas supplied by the compressor 400, and utilize the volume buffering effect of the internal cavity to offset the pressure fluctuations that may occur during the delivery of hydrogen chloride gas from the compressor 400.

[0078] In this embodiment, the synergistic effect of the first buffer tank 210 and the second buffer tank 220 can mix the dehydrated hydrogen chloride gas with the undehydrated hydrogen chloride gas, which helps to meet the raw material requirements of the trichlorosilane synthesis device 700.

[0079] Meanwhile, by utilizing the pressure stabilizing function of the second buffer tank 220, the pressure of hydrogen chloride gas can be stabilized within a range that matches the feeding requirements of the trichlorosilane synthesis unit 700, and finally stably delivered to the synthesis unit through the second gas outlet 222, which helps to ensure the production quality of trichlorosilane.

[0080] In some embodiments, the first pipe 10 and the third pipe 30 are connected by a tee structure to connect the gas supply pipe 100 to the scrubbing tower 300. The tee structure can be provided on the third pipe 30, that is, on the pipe between the first buffer tank 210 and the second buffer tank 220.

[0081] One end of the three-way structure is connected to the third pipe 30, and the other end is connected to the second pipe 20, so that the three-way structure can divert the hydrogen chloride gas in the third pipe 30 to the first pipe 10, thereby guiding the hydrogen chloride gas to the scrubbing tower 300.

[0082] In some embodiments of this application, the tee structure includes a tee connector 230, which includes a first end 231, a second end 232 and a third end 233. The first end 231 and the second end 232 are connected to the third pipe 30, and the third end 233 is connected to the second pipe 20.

[0083] The first end 231 and the second end 232 are respectively connected to the two sections of the third pipe 30. That is, the third pipe 30 is split into a front section and a rear section by the tee connector 230. The front section is connected to the first outlet 212 of the first buffer tank 210 and the first end 231 of the tee connector 230. The rear section is connected to the second end 232 of the tee connector 230 and the third inlet 223 of the second buffer tank 220, thereby forming the main channel for the transport of wet hydrogen chloride.

[0084] The third end 233 is connected to the second pipeline 20 that transports dehydrated dry hydrogen chloride. The side wall of the tee connector 230 has a pre-set diversion interface for the third end 233, which is connected to the second inlet 310 of the washing tower 300 through the first pipeline 10.

[0085] In this embodiment, the three-way structure, through the series connection of the first end 231 and the second end 232 to the third pipe 30, ensures the stability of the mainstream hydrogen chloride gas delivery and reduces the disturbance of the diverted gas flow from the source. At the same time, the connection of the third end 233 to the second pipe 20 allows the hydrogen chloride gas to be delivered into the scrubbing tower 300.

[0086] In some embodiments, the tee structure further includes a figure-eight blind flange 240, which is disposed on the third pipe 30 and is located between the tee joint 230 and the second buffer tank 220.

[0087] The figure-eight blind flange 240 is configured to prevent hydrogen chloride gas from flowing from the first buffer tank 210 to the second buffer tank 220.

[0088] The figure-eight blind flange 240 (figure-eight blind flange) can have two states: a blind flange and a through flange. Under normal dehydration conditions, the figure-eight blind flange 240 is in a completely closed blind flange state, and its sealing surface is tightly fitted with the flange face of the rear section of the third pipe 30. This prevents hydrogen chloride gas from entering the second buffer tank 220, and it can only enter the first pipe 10 through the third end 233 on the side wall of the tee joint 230, and then flow to the washing tower 300 to complete the dehydration treatment.

[0089] When the scrubbing tower 300 needs to be shut down for maintenance, or when the supply of hydrogen chloride gas needs to be increased, the figure-eight blind flange 240 can be rotated to the through plate state, so that the downstream section of the third pipeline 30 can be restored to conduction. At this time, wet hydrogen chloride can directly enter the second buffer tank 220 through the downstream section of the third pipeline 30.

[0090] In some embodiments, the dehydration apparatus further includes a condensation device 500, which includes a fourth inlet 510 and a fourth outlet 520. The fourth inlet 510 is connected to the second outlet 320, and the fourth outlet 520 is connected to the third inlet 410.

[0091] The fourth inlet 510 can be sealed and connected to the second outlet 320 of the scrubbing tower 300 to receive the gas mixture discharged from the scrubbing tower 300, which includes dehydrated hydrogen chloride gas.

[0092] The fourth outlet 520 is connected to the third inlet 410 of the compressor 400, which delivers the dehydrated dry gas to the compressor 400 so that the compressor 400 can pressurize the gas.

[0093] The condenser 500 can fully liquefy the residual chlorosilane vapors carried in the outlet gas of the scrubbing tower 300 based on the boiling point difference between chlorosilane and hydrogen chloride, while hydrogen chloride and hydrogen gas remain in the gas phase. This allows chlorosilane to be separated and recovered from the gas phase, preventing it from entering the compressor 400 with the gas flow, thus effectively ensuring the purity of hydrogen chloride.

[0094] In some embodiments, the scrubbing tower 300 includes a packing element that is detachably disposed within the scrubbing tower 300.

[0095] The packing components can be detachably connected to the scrubbing tower 300 body via flanges or quick-release couplings, facilitating periodic disassembly and replacement. When the packing components require maintenance due to blockage or corrosion, operators can remove them by disassembling the connectors, replace them with new ones, and reinstall them without shutting down the machine or performing large-scale equipment disassembly.

[0096] This application's embodiment achieves rapid maintenance and replacement of the internal components of the scrubbing tower 300 through a removable packing layer design. This structure significantly reduces equipment downtime, avoids system shutdowns due to packing blockage or corrosion, and supports on-demand packing replacement, reducing resource waste and improving the long-term operational reliability of the system.

[0097] For example, the packing element is a modular packing assembly made of corrosion-resistant material, which is connected to the main body of the scrubbing tower 300 via a flange or quick-release joint. For example, the packing element can be a corrugated packing module or a structured packing module.

[0098] In some embodiments, the inner wall of the scrubbing tower 300 is provided with a protective layer, which is a polytetrafluoroethylene layer or a titanium alloy layer.

[0099] The inner wall of the scrubbing tower 300 is lined with a polytetrafluoroethylene (PTFE) layer or a titanium alloy layer. The chemical inertness of the PTFE or titanium alloy layer can reduce the reaction between the chlorosilane liquid and the equipment material, thus avoiding equipment damage caused by corrosion.

[0100] Therefore, this embodiment improves the corrosion resistance of the scrubbing tower 300 through the protective layer, thereby helping to extend the service life of the scrubbing tower 300.

[0101] Secondly, embodiments of this application provide a trichlorosilane production system, including a hydrogen chloride synthesis device 600, a trichlorosilane synthesis device 700, a synthesis liquid storage tank 900, and a dehydration device as described in any of the above embodiments.

[0102] The hydrogen chloride synthesis unit 600 has a first discharge port 610, which is connected to the first inlet 110 of the gas supply pipeline 100.

[0103] The hydrogen chloride synthesis unit 600, serving as the source of hydrogen chloride gas, has a first discharge port 610 that can be sealed and connected to the first inlet 110 of the gas supply pipeline 100 in the dehydration unit. The hydrogen chloride synthesis unit 600 can transport the hydrogen chloride gas generated by the high-temperature combustion of chlorine and hydrogen to the gas supply channel, providing a raw material basis for the subsequent synthesis of trichlorosilane.

[0104] The trichlorosilane synthesis unit 700 includes a hydrogen chloride inlet 710, a silicon powder inlet 720, and a second discharge outlet 730. The hydrogen chloride inlet 710 is connected to a second gas outlet 222, and the second discharge outlet 730 is connected to the inlet of a scrubbing tower 300. The inlet 910 of the synthesis liquid storage tank 900 is connected to the outlet 330 of the scrubbing tower 300.

[0105] The trichlorosilane synthesis unit 700 is equipped with a silicon powder inlet 720 and a second discharge port 730. The second discharge port 730 is connected to the inlet of the washing tower 300 in the dehydration unit, which can transport the mixed gas generated by the reaction to the washing tower 300. After the washing tower 300 achieves gas-liquid separation by spraying with chlorosilane cold liquid, its outlet 330 is sealed and connected to the inlet 910 of the synthesis liquid storage tank 900. This allows the liquefied trichlorosilane and silicon tetrachloride to be temporarily stored in the synthesis liquid storage tank 900, providing qualified raw materials for subsequent distillation and purification processes, while avoiding resource waste caused by the emission of chlorosilane with the tail gas.

[0106] Since the trichlorosilane production system in this application embodiment has the dehydration device in any of the above embodiments, the trichlorosilane production system also has the beneficial effects of the dehydration device in any of the above embodiments.

[0107] In other words, the trichlorosilane production system of this embodiment directly connects the gas supply pipeline 100, the buffer tank and the washing tower 300, and uses the chlorosilane liquid in the existing process as the dehydration medium. There is no need to add independent equipment such as concentrated sulfuric acid drying tower, thereby effectively reducing equipment investment costs and space occupation.

[0108] In some embodiments, the trichlorosilane production system further includes a separation component 800, which includes a cyclone separator 810 and a syngas filter 820.

[0109] The trichlorosilane synthesis unit 700, cyclone separator 810, synthesis gas filter 820 and scrubbing tower 300 are connected in sequence.

[0110] Cyclone separator 810 is used to separate the product gas from the mixed gas discharged from trichlorosilane synthesis unit 700. Synthesis gas filter 820 is used to further separate silicon powder from the product gas.

[0111] The second discharge port 730 of the trichlorosilane synthesis unit 700 can be connected to the inlet of the cyclone separator 810 via a sealed pipe. The outlet of the cyclone separator 810 can be connected to the inlet of the synthesis gas filter 820, and the outlet of the synthesis gas filter 820 can be connected to the inlet of the scrubbing tower 300. In this way, the cyclone separator 810 can remove most of the suspended silica powder from the mixed gas discharged from the second discharge port 730. Subsequently, the synthesis gas filter 820 can finely filter out the residual suspended silica powder in the gas, thereby improving the purity of the mixed gas.

[0112] Cyclone separator 810 can be used as a primary coarse separator. The mixed gas enters the cavity of cyclone separator 810 tangentially. During the rotation, silicon powder particles with a density much greater than that of the gas are thrown against the wall due to inertial force and fall down the wall into the ash hopper at the bottom, thus achieving the separation of large silicon powder particles.

[0113] Syngas filter 820 can be used as a secondary separation device. Its filter element can be made of polytetrafluoroethylene membrane filter material, which can remove fine silica particles and trace silica deposits that were not removed by cyclone separator 810.

[0114] Therefore, in this embodiment of the application, the silicon powder in the mixed gas discharged from the trichlorosilane synthesis device 700 can be separated by the separation component 800, thereby achieving gas-solid separation.

[0115] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the utility models disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this application are indicated by the following claims.

[0116] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. A dehydration device, applied in a trichlorosilane production system, characterized in that, include: A gas supply pipeline (100) includes a first inlet (110) and a first outlet (120), wherein the first inlet (110) is used to connect to a hydrogen chloride gas source; A buffer assembly (200) includes a first air inlet (211), a second air inlet (221), and a second air outlet (222). The first air inlet (211) is connected to the first outlet (120), and the second air outlet (222) is used to connect to the trichlorosilane synthesis device (700). A scrubbing tower (300) includes a second inlet (310) and a second outlet (320). The second inlet (310) is connected to the gas supply pipeline (100) through a first pipeline (10). The scrubbing tower (300) is equipped with a chlorosilane cold liquid spraying device. The compressor (400) includes a third inlet (410) and a third outlet (420), the third inlet (410) being connected to the second outlet (320), and the third outlet (420) being connected to the second air inlet (221) via a second pipe (20).

2. The dehydration device according to claim 1, characterized in that, The buffer component (200) includes: The first buffer tank (210) includes the first air inlet (211) and the first air outlet (212). The second buffer tank (220) includes a second air inlet (221), a second air outlet (222) and a third air inlet (223); The third pipe (30) has one end connected to the first air outlet (212) and the other end connected to the third air inlet (223).

3. The dehydration device according to claim 2, characterized in that, The first pipe (10) and the third pipe (30) are connected by a tee structure so that the gas supply pipe (100) is connected to the scrubbing tower (300); One end of the three-way structure is connected to the third pipe (30), and the other end is connected to the second pipe (20), wherein the three-way structure is used to divert hydrogen chloride gas to the scrubbing tower (300).

4. The dehydration device according to claim 3, characterized in that, The tee structure includes a tee connector (230), which includes a first end (231), a second end (232) and a third end (233). The first end (231) and the second end (232) are both connected to the third pipe (30), and the third end (233) is connected to the first pipe (10).

5. The dehydration device according to claim 4, characterized in that, The tee structure also includes a figure-eight blind flange (240), which is disposed on the third pipe (30) and is located between the tee joint (230) and the second buffer tank (220); The figure-eight blind plate (240) is configured to prevent the hydrogen chloride gas from flowing from the first buffer tank (210) to the second buffer tank (220).

6. The dehydration apparatus according to any one of claims 1 to 5, characterized in that, It also includes a condenser (500), which includes a fourth inlet (510) and a fourth outlet (520), the fourth inlet (510) being connected to the second outlet (320) and the fourth outlet (520) being connected to the third inlet (410).

7. The dehydration apparatus according to claim 6, characterized in that, The washing tower (300) includes a packing element that is detachably disposed within the washing tower (300).

8. The dehydration apparatus according to claim 6, characterized in that, The inner wall of the washing tower (300) is provided with a protective layer, which is a polytetrafluoroethylene layer or a titanium alloy layer.

9. A trichlorosilane production system, characterized in that, include: The dehydration apparatus according to any one of claims 1 to 8; A hydrogen chloride synthesis apparatus (600) having a first discharge port (610) connected to the first inlet (110) of the gas supply pipeline (100); The trichlorosilane synthesis apparatus (700) includes a hydrogen chloride inlet (710), a silicon powder inlet (720), and a second discharge port (730). The hydrogen chloride inlet (710) is connected to the second gas outlet (222), and the second discharge port (730) is connected to the inlet of the scrubbing tower (300). A synthesis liquid storage tank (900) is provided, with its inlet (910) connected to the outlet (330) of the washing tower (300).

10. The trichlorosilane production system according to claim 9, characterized in that, It also includes a separation assembly (800), which includes a cyclone separator (810) and a syngas filter (820); The trichlorosilane synthesis unit (700), the cyclone separator (810), the synthesis gas filter (820), and the scrubbing tower (300) are connected in sequence; The cyclone separator (810) is used to separate the product gas from the mixed gas discharged from the trichlorosilane synthesis unit (700); The synthesis gas filter (820) is used to separate silicon powder from the product gas.

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