An apparatus and method for removing carbon deposits in the production of phenyltrichlorosilane.

Abstract

This invention provides an apparatus and method for removing carbon deposits in the production of phenyltrichlorosilane. The apparatus includes a high-boiling-point decarbonization vessel, a condenser, a reflux tank, a cold trap, and a vacuum unit. The vacuum unit is connected to the high-boiling-point decarbonization vessel, condenser, and cold trap via a negative pressure pipeline to create negative pressure in these components. The high-boiling-point decarbonization vessel is configured as a pressure vessel and includes a heating device. This invention provides a separate carbon deposit removal device, processing carbon powder smaller than 5μm that cannot be handled by a carbon powder filter to obtain carbon powder-free raw material for the rectification section. This reduces pump wear and frequent blockages in the rectification system, preventing continuous production. The apparatus provided by this invention has the advantages of requiring no special equipment, a short removal process route, high efficiency, and completely eliminating the impact of carbon-containing materials entering the rectification section, making it suitable for fine chemical industrial production.

Description

Technical Field

[0001] This invention relates to the technical field of removing carbon deposits in the production of phenyltrichlorosilane, and specifically to an apparatus and method for removing carbon deposits in the production of phenyltrichlorosilane. Background Technology

[0002] Phenylacetyltrichlorosilane, as a thermosetting polysiloxane polymer with a highly cross-linked structure, has a promising market. Currently, the main method for producing phenyltrichlorosilane is the thermal shrinkage method. Chlorobenzene and trichlorosilane react continuously at high temperatures through various types of reactors to generate phenyltrichlorosilane. However, during the production process, some organic matter carbonizes under high-temperature reaction conditions, forming carbon powder mixed in the material. Therefore, removing the carbon deposits from the mixture is crucial, but the technology and equipment are not yet mature.

[0003] Currently, most online carbon removal equipment applicable to the outlet of phenyltrichlorosilane reactors is ceramic filter equipment, which has a filter particle size of 5μm. It cannot filter and intercept carbon powder smaller than 5μm. This part of the carbon powder enters the rectification section with the material, thus affecting the continuous production of the rectification section. Summary of the Invention

[0004] In view of this, the present invention provides an apparatus and method for removing carbon deposits in the production of phenyltrichlorosilane. For the process route in which trichlorosilane and chlorobenzene are continuously reacted at high temperatures through different types of reactors, the present invention can overcome the problem that carbon deposits cause the distillation and purification process to be unable to continue, which in turn leads to reactor shutdown.

[0005] To address the technical problems mentioned in the background section, the present invention adopts the following technical solution:

[0006] In a first aspect, the present invention provides an apparatus for removing carbon deposits in the production of phenyltrichlorosilane, the apparatus comprising:

[0007] High-boiling-point carbon removal vessel, condenser, reflux tank, cold trap, and vacuum unit;

[0008] The top of the high-boiling-point carbon removal vessel is connected to the inlet of the condenser via a pipeline. The outlet of the condenser is connected to the first inlet of the reflux tank and the inlet of the cold trap via pipelines. The outlet of the cold trap is connected to the second inlet of the reflux tank. The vacuum unit is connected to the high-boiling-point carbon removal vessel, the condenser, and the cold trap via negative pressure pipelines to provide negative pressure for the high-boiling-point carbon removal vessel, the condenser, and the cold trap.

[0009] The high-boiling-point carbon removal vessel is configured as a pressure vessel and includes a heating device.

[0010] Furthermore, the bottom of the high-boiling-point carbon removal vessel is connected to a carbon discharge powder and a high-boiling-point outlet pipeline, which are in communication with the interior of the high-boiling-point carbon removal vessel.

[0011] Furthermore, the bottom of the reflux tank is connected to a chlorosilane outlet pipeline, which is in communication with the interior of the reflux tank.

[0012] Furthermore, the high-boiling-point decarbonization vessel is equipped with a stirring device inside; and / or the outer wall of the high-boiling-point decarbonization vessel is equipped with a jacketed heating system, wherein the heat source medium for the jacketed heating system includes either heat transfer oil or saturated steam, and the heating temperature of the heat transfer oil or saturated steam is 250-300℃.

[0013] Furthermore, the condenser has a shell-and-tube structure, the cooling medium of the condenser is circulating water, and the circulating water flows through the shell structure of the condenser; and / or

[0014] The cold trap has a shell-and-tube structure, and the cooling medium of the cold trap is frozen brine, which flows through the shell structure of the cold trap.

[0015] Furthermore, the vacuum unit includes a liquid ring pump and a vacuum pump, the pressure of the vacuum unit is -95kPa to -75kPa, and the vacuum unit also includes an exhaust port.

[0016] Furthermore, the sealing fluid of the vacuum unit is chlorobenzene.

[0017] Secondly, the present invention provides a method for removing carbon deposits using the apparatus described above, the method comprising the following steps:

[0018] S1: The crude material to be decarbonized is conveyed to the high-boiling carbon removal kettle;

[0019] S2: Control the high-boiling decarbonization kettle to heat the crude material, and control the vacuum unit to draw negative pressure on the high-boiling decarbonization kettle to distill the crude material, so that the light components in the crude material are distilled and vaporized, and enter the condenser through the pipeline;

[0020] S3: Control the condenser to condense the vaporized light components, and the resulting condensate enters the reflux tank through the first inlet of the reflux tank via a pipeline; the non-condensable gas in the condenser enters the cold trap through a pipeline under the negative pressure condition of the vacuum unit.

[0021] S4: Control the cold trap to perform secondary condensation on the non-condensable gas. The condensate obtained from the secondary condensation enters the reflux tank through the second inlet of the reflux tank via a pipeline. The material in the reflux tank is used to supply the distillation section for stable production.

[0022] Furthermore, in the method: a stirring device is provided inside the high-boiling carbon removal kettle;

[0023] In S2: The heat source medium, heat transfer oil, is introduced into the high-boiling decarbonization kettle. The return temperature of the heat transfer oil is controlled at 250-260℃, and the inlet temperature is controlled at 280-300℃ to preheat the high-boiling decarbonization kettle. When the top temperature of the high-boiling decarbonization kettle reaches 130-150℃, the vacuum unit is started to draw negative pressure into the high-boiling decarbonization kettle, and the pressure at the top of the kettle is controlled at -85kpa ​​to -65kpa. At the same time, the crude material is conveyed into the high-boiling decarbonization kettle and subjected to vacuum distillation under the stirring of the stirring device.

[0024] Furthermore, the method further includes: S5: Carbon powder, high-boiling-point substances, and unvaporized phenyltrichlorosilane are deposited at the bottom of the high-boiling-point carbon removal vessel, and the phenyltrichlorosilane continues to vaporize under continuous heating and stirring, and is then condensed and collected using the same method as in S3; the material collected in the reflux tank is supplied to the rectification section for stable production;

[0025] S6: When the liquid level in the high-boiling decarbonization reactor exceeds 60%, stop feeding the crude material and continue heating and distillation until the liquid level in the reflux tank stops rising. Then stop heating, fully reflux the vacuum unit, open the slag discharge valve located at the bottom of the high-boiling decarbonization reactor, and discharge and process the carbon-containing high-boiling substances.

[0026] The beneficial effects of the above-described technical solution of the present invention are as follows:

[0027] This invention provides an apparatus and method for removing carbon deposits in the production of phenyltrichlorosilane. The apparatus includes: a high-boiling-point decarbonization vessel, a condenser, a reflux tank, a cold trap, and a vacuum unit. The top of the high-boiling-point decarbonization vessel is connected to the inlet of the condenser via a pipeline. The outlet of the condenser is connected to the first inlet of the reflux tank and the inlet of the cold trap via pipelines. The outlet of the cold trap is connected to the second inlet of the reflux tank. The vacuum unit is connected to the high-boiling-point decarbonization vessel, the condenser, and the cold trap via a negative pressure pipeline to create negative pressure in the high-boiling-point decarbonization vessel, the condenser, and the cold trap. The high-boiling-point decarbonization vessel is configured as a pressure vessel and includes a heating device.

[0028] This invention, by installing a separate carbon removal device after the reactor, processes carbon powder smaller than 5μm, which cannot be handled by a carbon filter, to obtain carbon-free feedstock for the rectification section. This reduces pump wear and frequent clogging of rectification system equipment (packing, flow meters, level gauges, regulating valves, etc.), preventing continuous production. The carbon removal device provided by this invention has the advantages of requiring no special equipment, having a short removal process route, high efficiency, and completely eliminating the impact of carbon-containing materials entering the rectification section, making it suitable for fine chemical industrial production. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the device for removing carbon deposits in the production of phenyltrichlorosilane.

[0030] 1. High-boiling carbon removal vessel; 2. Condenser; 3. Reflux tank; 4. Cold trap; 5. Vacuum unit; 6. Transfer pump; 7. Heat transfer oil or saturated steam outlet pipeline; 8. Heat transfer oil or saturated steam inlet pipeline; 9. Carbon-containing chlorosilane feed pipeline; 10. Chlorosilane outlet pipeline after carbon removal; 11. Stirring device; 12. Carbon powder discharge and high-boiling outlet pipeline; 13. First condenser pipeline; 14. Condenser negative pressure extraction pipeline; 15. Second condenser pipeline; 16. Circulating water inlet pipeline; 17. Circulating water outlet pipeline; 18. Reflux tank chlorosilane outlet pipeline; 19. Chlorosilane to distillation pipeline after carbon removal; 20. Reflux brine inlet pipeline; 21. Reflux brine outlet pipeline; 22. Cold trap negative pressure extraction pipeline; 23. Tail gas pipeline; 24. Chlorobenzene inlet pipeline; 25. Chlorobenzene outlet pipeline; 26. Chlorosilane to distillation reflux pipeline after carbon removal; 27. Inert gas replacement pipeline; 28. Shielded pump. Detailed Implementation

[0031] To further understand the present invention, preferred embodiments of the present invention are described below in conjunction with examples. However, it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, and not for limiting the present invention.

[0032] The following is in conjunction with the appendix Figure 1 The apparatus and method for removing carbon deposits in the production of phenyltrichlorosilane in this invention are further explained and described.

[0033] In a first aspect, the present invention provides a device for removing carbon deposits in the production of phenyltrichlorosilane, the device comprising:

[0034] 1. High-boiling-point carbon removal vessel, 2. Condenser, 3. Reflux tank, 4. Cold trap, and 5. Vacuum unit;

[0035] The top of the high-boiling-point carbon removal vessel 1 is connected to the inlet of the condenser 2 via a pipeline. The outlet of the condenser 2 is connected to the first inlet of the reflux tank 3 and the inlet of the cold trap 4 via pipelines. The outlet of the cold trap 4 is connected to the second inlet of the reflux tank 3. The vacuum unit 5 is connected to the high-boiling-point carbon removal vessel 1, the condenser 2, and the cold trap 4 via a negative pressure pipeline, and is used to draw negative pressure into the high-boiling-point carbon removal vessel 1, the condenser 2, and the cold trap 4. The high-boiling-point carbon removal vessel 1 is configured as a pressure vessel and includes a heating device.

[0036] In existing technologies, carbon buildup occurs in various types of reaction devices, and the online carbon removal equipment in these devices cannot completely remove fine carbon particles, resulting in a viscous material that disrupts continuous distillation. To address these problems, this invention introduces a separate carbon removal device after the reaction device. This device processes carbon particles smaller than 5μm, which cannot be handled by carbon filters, to provide carbon-free feedstock to the distillation section. This reduces pump wear and frequent clogging of distillation system equipment (packing, flow meters, level gauges, regulating valves, etc.), preventing continuous production. (See appendix) Figure 1 This invention provides a carbon removal device for the production of phenyltrichlorosilane. The carbon removal device mainly includes: a high-boiling carbon removal vessel 1, a condenser 2, a reflux tank 3, a cold trap 4, and a vacuum unit 5. After the crude material is pretreated by the reactor synthesis reaction, it is transported to the high-boiling carbon removal vessel 1 by a pump. In the high-boiling carbon removal vessel 1, it is heated by a heating device and subjected to vacuum distillation under negative pressure by the vacuum unit 5. Taking advantage of the different boiling points of carbon powder, high boiling point, phenyltrichlorosilane, chlorobenzene, trichlorosilane, silicon tetrachloride, and benzene in the crude material, the light components chlorobenzene, trichlorosilane, silicon tetrachloride, benzene, and a large amount of phenyltrichlorosilane are vaporized from the top of the high-boiling carbon removal vessel 1 and enter the condenser 2. After primary condensation in the condenser 2, it enters the reflux tank 3 through a pipeline. The non-condensable gaseous medium in the primary condenser 2 enters the cold trap 4 for secondary condensation. The condensed liquid phase enters the reflux tank 3. The material collected in the reflux tank 3 is used for continuous and stable production in the rectification section. Simultaneously, in the high-boiling carbon removal vessel 1, the heavy component carbon powder, high-boiling mixture, and a small amount of phenyltrichlorosilane are continuously distilled. Part of the phenyltrichlorosilane vaporizes and flows from the top of the column to the condenser 2, then enters the reflux tank 3 via the aforementioned steps. The high-boiling matter, carbon powder, and trace amounts of phenyltrichlorosilane mixture at the bottom of the vessel are discharged and processed. The carbon removal device provided by this invention has the advantages of requiring no special equipment, having a short removal process route, high efficiency, and completely eliminating the impact of carbon-containing materials entering the rectification section, making it suitable for fine chemical industrial production.

[0037] According to some embodiments of the present invention, the high-boiling-point decarbonization vessel 1 is internally equipped with a stirring device 11. The high-boiling-point decarbonization vessel 1 in this invention is configured as a pressure vessel with a volume of 10-30 m³. 3 The specific volume is selected according to the production scale of the equipment. The high-boiling carbon removal kettle 1 is equipped with a stirring device 11, which can be driven by a variable frequency motor to continuously stir the high-boiling carbon removal kettle 1 during the heating and distillation process to ensure that the reaction is thorough.

[0038] According to some embodiments of the present invention, the outer wall of the high-boiling carbon removal vessel 1 is provided with a jacketed heating system, and the heat source medium for the jacketed heating system includes either heat transfer oil or saturated steam. The heating temperature of the heat transfer oil or saturated steam is 250-300°C. Specifically, the bottom of the jacketed heating system is connected to a heat transfer oil or saturated steam inlet pipeline 8, and the inlet pipeline communicates with the interior of the jacket; the top of the jacketed heating system is connected to a heat transfer oil or saturated steam outlet pipeline 7, and the outlet pipeline communicates with the interior of the jacket.

[0039] According to some embodiments of the present invention, an inert gas replacement pipeline 27 is connected to the top of the high-boiling-point decarbonization vessel 1, and the inert gas replacement pipeline 27 communicates with the interior of the high-boiling-point decarbonization vessel 1. Nitrogen is generally selected as the inert gas. The inert gas replacement pipeline 27 is not opened during continuous production, but is mainly opened when excessive carbon buildup in the high-boiling-point decarbonization vessel 1 necessitates carbon removal, and during shutdown maintenance.

[0040] According to some embodiments of the present invention, the bottom of the high-boiling-point carbon removal vessel 1 is connected to a carbon discharge powder and a high-boiling-point outlet pipeline 12, which communicates with the interior of the high-boiling-point carbon removal vessel 1. In the carbon removal apparatus provided by the present invention, crude material is heated and distilled in the high-boiling-point carbon removal vessel 1, wherein the light components enter the condenser 2, while the heavy components (carbon powder, high-boiling mixture, and a small amount of phenyltrichlorosilane) are continuously stirred and distilled in the high-boiling-point carbon removal vessel 1. After some of the phenyltrichlorosilane is vaporized, it flows from the top of the vessel to the condenser 2, while the high-boiling-point material, carbon powder, and trace amount of phenyltrichlorosilane mixture at the bottom of the vessel are discharged from the bottom of the vessel via the carbon discharge powder and the high-boiling-point outlet pipeline 12. Further, a shielded pump 28 is also connected to the rear end of the carbon discharge powder and the high-boiling-point outlet pipeline 12, through which the carbon deposits are pumped to an incinerator or a hazardous waste container for disposal.

[0041] According to some embodiments of the present invention, the condenser 2 is a shell-and-tube condenser 2. The cooling medium of the condenser 2 is selected as circulating water, wherein the shell side is circulated with circulating water and the tube side is circulated with light components after carbon removal. Specifically, the bottom of the shell structure of the condenser 2 is connected to a circulating water inlet pipe 16, and the top of the shell structure of the condenser 2 is connected to a circulating water outlet pipe 17. A first condensation pipe 13 is connected between the condenser 2 and the reflux tank 3, and a carbon removal chlorosilane outlet pipe 10 is connected between the condenser 2 and the high-boiling carbon removal vessel 1. The light components after carbon removal enter the condenser 2 through the carbon removal chlorosilane outlet pipe 10, are condensed by the condenser 2 into a liquid phase, and the liquid phase is then returned to the reflux tank 3 through the first condensation pipe 13.

[0042] According to some embodiments of the present invention, the cold trap 4 is a shell-and-tube structure, and the cooling medium of the cold trap 4 is -35°C chilled brine. The shell side flows through the -35°C chilled brine, and the tube side flows through non-condensable gas entering from the condenser 2. Specifically, the top of the shell structure of the cold trap 4 is connected to a chilled brine inlet pipe 20, and the bottom of the shell structure of the cold trap 4 is connected to a chilled brine outlet pipe 21. The non-condensable gas entering from the condenser 2 is fully cooled by the 35°C chilled brine and becomes a liquid phase, flowing to the return tank 3 through the second condensation pipe 15.

[0043] According to some embodiments of the present invention, the vacuum unit 5 includes a liquid ring pump and a vacuum pump, and the pressure of the vacuum unit 5 is -95kPa to -75kPa. The pressure of the vacuum unit 5 is related to the raw material composition of the crude material. Through exploration, the present invention believes that setting the pressure of the vacuum unit 5 to -95kPa to -75kPa is more appropriate.

[0044] According to some embodiments of the present invention, the vacuum unit 5 further includes an exhaust port, which is connected to an exhaust pipeline 23. A cold trap negative pressure pipeline 22 is connected between the cold trap 4 and the vacuum unit 5. The remaining non-liquefied non-condensable gas is drawn into the vacuum unit 5 through the cold trap negative pressure pipeline 22 and then discharged through the exhaust pipeline 23.

[0045] According to some embodiments of the present invention, the vacuum unit 5 is connected to a chlorobenzene inlet pipeline 24 and a chlorobenzene outlet pipeline 25, and the sealing fluid of the vacuum unit 5 is chlorobenzene. Water is not suitable as the sealing fluid in this invention; if water is used, the chlorosilane-containing tail gas entering the vacuum unit 5 will react with the water. In this invention, the vacuum unit 5 is a combination of a liquid ring pump and a vacuum pump. The vacuum pump is used to create negative pressure in the condenser 2 and the cold trap 4, achieving complete separation of the gas and liquid phases through the negative pressure state. The sealing fluid medium is chlorobenzene, the heat exchange medium is water at 7°C, and the pressure is controlled between -95 kPa and -75 kPa. The tail gas of the vacuum unit 5 is discharged to the chlorine-containing tail gas network through the tail gas pipeline 23.

[0046] According to some embodiments of the present invention, the reflux tank 3 is an atmospheric pressure tank, and the volume of the reflux tank 3 is set according to the volume of the high-boiling carbon removal vessel 1, and can be set to 10-20m³. 3 The bottom of the reflux tank 3 is connected to the chlorosilane outlet pipeline 18, and the outlet of the chlorosilane outlet pipeline 18 is connected to the transfer pump 6. The transfer pump 6 is also connected to the chlorosilane decarbonization reflux pipeline 26 and the chlorosilane decarbonization reflux pipeline 19.

[0047] Secondly, the present invention provides a method for removing carbon deposits using the apparatus described above, the method comprising the following steps:

[0048] S1: The crude material to be decarbonized is conveyed to the high-boiling carbon removal vessel 1;

[0049] S2: Control the high-boiling decarbonization vessel 1 to heat the crude material, and control the vacuum unit 5 to draw negative pressure on the high-boiling decarbonization vessel 1 to distill the crude material, so that the light components in the crude material are distilled and vaporized, and enter the condenser 2 through the pipeline;

[0050] S3: The condenser 2 is controlled to condense the vaporized light components, and the resulting condensate enters the return tank 3 through the first inlet of the return tank 3 via a pipeline; the non-condensable gas in the condenser 2 enters the cold trap 4 through a pipeline under the negative pressure condition of the vacuum unit 5.

[0051] S4: Control the cold trap 4 to perform secondary condensation on the non-condensable gas. The condensate obtained from the secondary condensation enters the reflux tank 3 through the second inlet of the reflux tank 3 via a pipeline. The material in the reflux tank 3 is used to supply the distillation section for stable production.

[0052] According to some embodiments of the present invention, in the method: a stirring device 11 is provided inside the high-boiling decarbonization kettle 1; in S2: heat transfer oil, the heat source medium, is introduced into the high-boiling decarbonization kettle 1, and the return temperature of the heat transfer oil is controlled at 250-260°C and the inlet temperature of the heat transfer oil is controlled at 280-300°C to preheat the high-boiling decarbonization kettle 1; when the top temperature of the high-boiling decarbonization kettle 1 reaches 130-150°C, the vacuum unit 5 is started to draw negative pressure into the high-boiling decarbonization kettle 1, and the pressure at the top of the kettle is controlled at -85kpa ​​to -65kpa. At the same time, the crude material is transported into the high-boiling decarbonization kettle 1 and subjected to vacuum distillation under the stirring of the stirring device 11.

[0053] According to some embodiments of the present invention, the method further includes: S5: Carbon powder, high-boiling-point substances, and unvaporized phenyltrichlorosilane are deposited at the bottom 1 of the high-boiling-point decarbonization vessel. The phenyltrichlorosilane continues to vaporize under continuous heating and stirring, and is then condensed and collected using the same method as in S3. The material collected in the reflux tank 3 is used for stable production in the rectification section; S6: When the liquid level of the high-boiling-point decarbonization vessel 1 exceeds 60%, the feeding of the crude material is stopped, and heating and distillation continue until the liquid level of the reflux tank 3 stops rising. Heating is then stopped, the vacuum unit 5 is fully refluxed, and the slag discharge valve located at the bottom of the high-boiling-point decarbonization vessel 1 is opened to discharge the carbon-containing high-boiling-point substances.

[0054] Specifically, when the liquid level of the high-boiling decarbonization vessel 1 exceeds 60%, the feeding of the crude material is stopped, and at the same time, the inert gas replacement pipeline 27 is opened to supply nitrogen gas. Under the pressure of nitrogen gas, the carbon-containing high-boiling substances are discharged from the bottom of the high-boiling decarbonization vessel 1 and sent to the incinerator or hazardous waste bin for disposal.

[0055] The present invention will be further described below through some specific embodiments.

[0056] Example 1

[0057] like Figure 1 As shown, this invention provides an apparatus for removing carbon deposits during the production of phenyltrichlorosilane. The apparatus includes:

[0058] 1. High-boiling carbon removal vessel, 2. Condenser, 3. Reflux tank, 4. Cold trap, and 5. Vacuum unit.

[0059] The method for removing carbon deposits using the apparatus provided in this invention is as follows:

[0060] The material synthesized in the reactor is pretreated by an online carbon removal filter to intercept carbon powder with a particle size greater than 5μm. After being cooled by a quench tower, the material is transported to a crude product storage tank. The crude product in the crude product storage tank is then pumped to a high-boiling carbon removal vessel 1. The crude product is heated in the high-boiling carbon removal vessel 1. During the heating process, the stirring device 11 continuously stirs the material, and it is distilled under negative pressure conditions by a vacuum unit 5. Taking advantage of the different boiling points of the materials, the light components (chlorobenzene, trichlorosilane, silicon tetrachloride, benzene, and a large amount of phenyltrichlorosilane) vaporize and enter the condenser 2. After condensation, the material goes to the reflux tank 3. The non-condensable gas enters the cold trap 4 for secondary condensation. The condensate from the secondary condensation enters the reflux tank 3. The material in the reflux tank 3 is transported to the raw material storage tank by a transfer pump 6 for stable production in the rectification section. The heavy components (carbon powder, high-boiling substances and unvaporized phenyltrichlorosilane) are deposited at the bottom of the high-boiling carbon removal vessel 1. The phenyltrichlorosilane continues to vaporize under continuous heating and stirring, and is then condensed and collected using the same method as described above. The remaining carbon-containing high-boiling substances are discharged from the bottom of the vessel and sent to an incinerator or hazardous waste bin for disposal.

[0061] Example of production start-up:

[0062] S1: The heat source medium, heat transfer oil, is introduced into the high-boiling decarbonization reactor 1, with the heat source medium entering from the bottom and exiting from the top. The return oil temperature is controlled at 250-260℃, and the inlet oil temperature is controlled at 280-300℃ to preheat the high-boiling decarbonization reactor 1;

[0063] S2: When the top temperature of the high boiling decarbonation vessel 1 reaches 130-150℃, start the vacuum unit 5 to draw negative pressure on the high boiling decarbonation vessel 1 and control the pressure at the top of the vessel to -85kpa~-65kpa. At the same time, start the crude product conveying pump 6 to convey the crude product into the high boiling decarbonation vessel 1 for heating and distillation. During this process, the stirring device 11 continuously stirs.

[0064] S3: After the crude material enters the high-boiling decarbonization kettle 1, it partially vaporizes and passes through the decarbonization powder and chlorosilane outlet pipeline 10 into the condenser 2. The liquid phase formed after condensation enters the reflux tank 3 through the first condensation pipeline 13. The non-condensable gas, under the negative pressure condition of the vacuum unit 5, enters the cold trap 4 through the negative pressure condenser pipeline 14 for secondary condensation. The liquid phase formed after condensation enters the reflux tank 3 through the second condensation pipeline 15. The liquid phase material in the reflux tank 3 is transported to the raw material storage tank for stable production in the rectification section. The condenser 2 is cooled by circulating water, and the cold trap 4 is cooled by -35℃ brine.

[0065] S4: Carbon powder, high-boiling substances and a small amount of phenyltrichloro are deposited at the bottom of the high-boiling carbon removal vessel 1. Phenyltrichloro is partially vaporized during continuous heating and then condensed and collected using the same method as in S3.

[0066] S5: When the liquid level of the high-boiling decarbonization vessel 1 exceeds 60%, stop feeding the crude material and continue heating and purification until the liquid level of the reflux tank 3 stops rising. Then stop heating, fully reflux the vacuum unit 5, close the gas phase valve at the top of the high-boiling decarbonization vessel 1, open the slag discharge valve at the bottom of the high-boiling decarbonization vessel 1, and transport the carbon-containing high-boiling material to the waste liquid tank or hazardous waste bin of the incineration unit for treatment.

[0067] S6: After the waste discharge is completed, open the crude product feed valve to flush the conveying pipeline. Then stop the conveying pump 6, and re-feed the pretreated material in the reaction section to continue the reaction in S1 to S5.

[0068] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship also changes accordingly.

[0069] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for removing carbon deposits in the production of phenyltrichlorosilane, characterized in that, The apparatus used in the method includes: High-boiling-point carbon removal vessel, condenser, reflux tank, cold trap, and vacuum unit; The top of the high-boiling carbon removal vessel is connected to the inlet of the condenser via a pipeline, and the outlet of the condenser is connected to the first inlet of the reflux tank and the inlet of the cold trap via pipelines. The outlet of the cold trap is connected to the second inlet of the reflux tank. The vacuum unit is connected to the high-boiling carbon removal vessel, condenser and cold trap through a negative pressure pipeline, and is used to draw negative pressure into the high-boiling carbon removal vessel, condenser and cold trap; The high-boiling-point carbon removal vessel is configured as a pressure vessel and includes a heating device. The method includes the following steps: S1: The crude material to be decarbonized is conveyed to the high-boiling carbon removal kettle; S2: Control the high-boiling decarbonization kettle to heat the crude material, and control the vacuum unit to draw negative pressure on the high-boiling decarbonization kettle to distill the crude material, so that the light components in the crude material are distilled and vaporized, and enter the condenser through the pipeline; S3: Control the condenser to condense the vaporized light components, and the resulting condensate enters the reflux tank through the first inlet of the reflux tank via a pipeline; the non-condensable gas in the condenser enters the cold trap through a pipeline under the negative pressure condition of the vacuum unit. S4: Control the cold trap to perform secondary condensation on the non-condensable gas. The condensate obtained from the secondary condensation enters the reflux tank through the second inlet of the reflux tank via a pipeline. The material in the reflux tank is used to supply the distillation section for stable production.

2. The method according to claim 1, characterized in that, In the method: The high-boiling-point carbon removal kettle is equipped with a stirring device inside. In S2: The heat source medium, heat transfer oil, is introduced into the high-boiling decarbonization kettle. The return temperature of the heat transfer oil is controlled at 250-260℃, and the inlet temperature is controlled at 280-300℃ to preheat the high-boiling decarbonization kettle. When the top temperature of the high-boiling decarbonization kettle reaches 130-150℃, the vacuum unit is started to draw negative pressure into the high-boiling decarbonization kettle, and the pressure at the top of the kettle is controlled at -85 kPa to -65 kPa. At the same time, the crude material is conveyed into the high-boiling decarbonization kettle and subjected to vacuum distillation under the stirring of the stirring device.

3. The method according to claim 2, characterized in that, The method further includes: S5: Carbon powder, high-boiling-point substances, and unvaporized phenyltrichlorosilane are deposited at the bottom of the high-boiling-point carbon removal vessel. The phenyltrichlorosilane continues to vaporize under continuous heating and stirring, and is then condensed and collected using the same method as in S3. The material collected in the reflux tank is supplied to the rectification section for stable production. S6: When the liquid level in the high-boiling decarbonization reactor exceeds 60%, stop feeding the crude material and continue heating and distillation until the liquid level in the reflux tank stops rising. Then stop heating, fully reflux the vacuum unit, open the slag discharge valve located at the bottom of the high-boiling decarbonization reactor, and discharge and process the carbon-containing high-boiling substances.

4. The method according to claim 1, characterized in that, The bottom of the high-boiling-point carbon removal vessel is connected to a carbon discharge powder and a high-boiling-point outlet pipeline, which are in communication with the interior of the high-boiling-point carbon removal vessel.

5. The method according to claim 1, characterized in that, The bottom of the reflux tank is connected to a chlorosilane outlet pipeline, which is in communication with the interior of the reflux tank.

6. The method according to claim 1, characterized in that, The high-boiling carbon removal kettle is equipped with a stirring device inside; and / or The outer wall of the high-boiling carbon removal vessel is equipped with a jacketed heating system. The heat source medium for the jacketed heating system includes either heat transfer oil or saturated steam, and the heating temperature of the heat transfer oil or saturated steam is 250-300℃.

7. The method according to claim 1, characterized in that, The condenser has a shell-and-tube structure, the cooling medium of the condenser is circulating water, and the circulating water flows through the shell structure of the condenser; and / or The cold trap has a shell-and-tube structure, and the cooling medium of the cold trap is frozen brine, which flows through the shell structure of the cold trap.

8. The method according to claim 1, characterized in that, The vacuum unit includes a liquid ring pump and a vacuum pump, and the pressure of the vacuum unit is -95 kPa to -75 kPa. The vacuum unit also includes an exhaust gas outlet.

9. The method according to claim 8, characterized in that, The sealing fluid of the vacuum unit is chlorobenzene.

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