A chlorosilane coupled rectification device and method based on heat pump rectification

Abstract

The present application relates to the technical field of chlorosilane rectification, and particularly to a chlorosilane coupled rectification device and method based on heat pump rectification, comprising a first rectification unit, a first rectification column, a first coupled reboiler connected to the first rectification column, and a first column bottom pump connected to the first coupled reboiler of the first rectification column; and a second rectification unit, comprising a second rectification column, a second coupled reboiler connected to the second rectification column, and a second steam reboiler connected to the second rectification column. The chlorosilane coupled rectification device based on heat pump rectification can reduce the use amount of steam by cross utilization of the materials at the top of the first rectification column and the second rectification column, and the materials at the top of the first rectification column provide heat source for the second rectification column, and the materials at the top of the second rectification column provide heat source for the first rectification column, thereby saving cost.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of chlorosilane rectification, and particularly to a chlorosilane coupled rectification device and method based on heat pump rectification. BACKGROUND

[0002] In the production of silane and polysilicon, the problem of chlorosilane rectification must be faced. In the chlorosilane rectification process, the traditional single rectification tower is used for rectification. At present, the heat medium and the cooling medium are consumed in large quantities in the production and operation process of the single rectification tower. The material temperature at the top of the rectification tower cannot be effectively utilized and is wasted, and more cooling medium is consumed for cooling. Therefore, the present application provides a chlorosilane coupled rectification device and method based on heat pump rectification. SUMMARY

[0003] In view of the above problems of the existing single rectification tower for chlorosilane rectification, the present application is proposed.

[0004] Therefore, one object of the present application is to provide a chlorosilane coupled rectification device based on heat pump rectification, which reduces the consumption of heat medium and cooling medium and saves costs.

[0005] To solve the above technical problems, the present application provides the following technical scheme: a chlorosilane coupled rectification device based on heat pump rectification, comprising: a first rectification unit, which comprises a first rectification tower, a first coupled reboiler connected to the first rectification tower, and a first tower kettle pump connected to the first rectification tower and the first coupled reboiler; and a second rectification unit, which comprises a second rectification tower, a second coupled reboiler connected to the second rectification tower, and a second steam reboiler connected to the second rectification tower, wherein one end of the first tower kettle pump is connected to the second rectification tower, the top of the first rectification tower is connected to the second coupled reboiler through a compressor, and the top of the second rectification tower is connected to the first coupled reboiler.

[0006] As a preferred scheme of the chlorosilane coupled rectification device based on heat pump rectification, the device further comprises a condensation unit, which comprises a first condensation component connected to the second coupled reboiler, a second condensation component connected to the first coupled reboiler, and a reflux component connected to the first condensation component and the second condensation component.

[0007] As a preferred scheme of the chlorosilane coupled rectification device based on heat pump rectification, the reflux component comprises a second reflux tank and a second tower top reflux pump connected to the second reflux tank, the first condensation component and the second condensation component are connected to the second reflux tank, one end of the second tower top reflux pump is connected to the second rectification tower and the second reflux tank, and a production pipeline is arranged between the second tower top reflux pump and the second rectification tower.

[0008] As a preferred scheme of the chlorosilane coupled rectification device based on heat pump rectification, the reflux assembly comprises a second reflux tank and a first reflux tank, a second overhead reflux pump connected with the second reflux tank, and a first overhead reflux pump connected with the first reflux tank, the first condensing assembly is connected with the first reflux tank; the second condensing assembly is connected with the second reflux tank, one end of the second overhead reflux pump is connected with the second rectification tower and the second reflux tank, the first overhead reflux pump is connected with the first rectification tower and the first reflux tank, and a production pipeline is arranged between the second overhead reflux pump and the second rectification tower.

[0009] As a preferred scheme of the chlorosilane coupled rectification device based on heat pump rectification, the first condensing assembly comprises a first condenser, a second condenser and a third condenser arranged in series, the second coupled reboiler is connected with the first condenser, and the first condenser, the second condenser and the third condenser are connected with the reflux assembly.

[0010] As a preferred scheme of the chlorosilane coupled rectification device based on heat pump rectification, the second condensing assembly comprises a fourth condenser and a fifth condenser arranged in series, the first coupled reboiler is connected with the fourth condenser, and the fourth condenser and the fifth condenser are connected with the reflux assembly.

[0011] As a preferred scheme of the chlorosilane coupled rectification device based on heat pump rectification, the second rectification tower, the second coupled reboiler and the second steam reboiler are connected with a second tower bottom pump.

[0012] The device has the beneficial effects that: the material at the top of the first rectification tower enters the second coupled reboiler to exchange heat, thereby providing heat for the second rectification tower and reducing the consumption of steam; similarly, the material at the top of the second rectification tower enters the first coupled reboiler to exchange heat, thereby providing heat for the first rectification tower and further reducing the consumption of steam.

[0013] Another object of the present application is to provide a chlorosilane coupled rectification method based on heat pump rectification, which reduces the consumption of heat medium and refrigerant and saves costs.

[0014] To solve the above technical problems, the application provides the following technical scheme: a chlorosilane coupled rectification method based on heat pump rectification, which comprises the following steps: chlorosilane material enters a first rectification tower to perform light component rectification, and then forms light components and heavy components; the light components are heated and evaporated by a first coupled reboiler, and then enter a second coupled reboiler from the top of the tower after being heated and pressurized by a compressor, and then are condensed; the heavy components are extracted and sent into a second rectification tower to perform heavy component rectification, and then form light components and heavy components again; the light components are evaporated from a liquid phase to a gas phase through a second coupled reboiler and a second steam reboiler, and then enter the first coupled reboiler from the gas phase at the top of the second rectification tower to perform condensation.

[0015] As a preferred scheme of the chlorosilane coupled rectification method based on heat pump rectification, the light components condensed in the second coupled reboiler enter a first condensing assembly to perform heat exchange, the gas after heat exchange is discharged, and the liquid is recycled through a reflux assembly; the gas phase condensed in the first coupled reboiler enters a second condensing assembly to perform heat exchange, the gas after heat exchange is discharged, and the liquid is recycled through a reflux assembly.

[0016] As a preferred scheme of the chlorosilane coupled rectification method based on heat pump rectification, the reflux assembly comprises a second reflux tank and a first reflux tank, the liquid in the first condensing assembly is recycled by the first reflux tank, and the liquid in the second condensing assembly is recycled by the second reflux tank.

[0017] The application has the following beneficial effects: through cross utilization of the materials at the top of the first rectification tower and the second rectification tower, the material at the top of the first rectification tower provides a heat source for the second rectification tower, and the material at the top of the second rectification tower provides a heat source for the first rectification tower, so that the use amount of steam can be reduced, and cost can be saved. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without any creative effort on the basis of these drawings.

[0019] Figure 1 A schematic diagram of Example 1 is shown;

[0020] Figure 2 A schematic diagram of Example 2 is shown;

[0021] Figure 3 A schematic diagram of Example 3 is shown;

[0022] Figure 4 A schematic diagram of Comparative Example 1 is shown.

[0023] In the figure: 100, first rectification unit; 101, first rectification column; 102, first coupled reboiler; 103, first column bottom pump; 200, second rectification unit; 201, second rectification column; 202, second coupled reboiler; 203, second steam reboiler; 104, compressor; 300, condensation unit; 301, first condensation assembly; 302, second condensation assembly; 303, reflux assembly; 303a, second reflux tank; 303b, second column top reflux pump; 303c, production pipeline; 303d, first reflux tank; 303e, first column top reflux pump; 301a, first condenser; 301b, second condenser; 301c, third condenser; 302a, fourth condenser; 302b, fifth condenser; 204, second column bottom pump. DETAILED DESCRIPTION

[0024] In order for those skilled in the art to have a better understanding of the present application, the present application will be further described in detail below in conjunction with the specific embodiments and the accompanying drawings.

[0025] The terms used in the present application are those general terms currently widely used in the art in consideration of the functions about the present application, but these terms can be changed according to the intention of those skilled in the art, precedents, or new technologies in the art. In addition, specific terms can be selected by the applicant, and in this case, the detailed meaning thereof will be described in the detailed description of the present application. Therefore, the terms used in the specification should not be understood as simple names, but based on the meaning of the terms and the overall description of the present application.

[0026] Example 1, Reference Figure 1 As a first embodiment of the present application, a chlorosilane coupled rectification device based on heat pump rectification is provided, which includes a first rectification unit 100 and a second rectification unit 200.

[0027] Among them, the first rectification unit 100 includes a first rectification column 101, a first coupled reboiler 102 connected to the first rectification column 101, and a first column bottom pump 103 connected to the first rectification column 101 and the first coupled reboiler 102; the material enters the first rectification column 101 for light rectification, and light components and heavy components are obtained by rectification separation.

[0028] Among them, the second rectification unit 200 includes a second rectification column 201, and a second coupled reboiler 202 and a second steam reboiler 203 connected to the second rectification column 201.

[0029] Further, one end of the first column bottom pump 103 is connected to the second rectification column 201, the top of the first rectification column 101 is connected to the second coupled reboiler 202 through the compressor 104, and the top of the second rectification column 201 is connected to the first coupled reboiler 102.

[0030] The light component formed after the distillation separation of the material in the first rectifying tower 101 is heated and evaporated into a gas phase by the first coupling reboiler 102, and enters the compressor 104 from the top of the first rectifying tower 101, and is sent to the second coupling reboiler 202 after being heated and pressurized by the compressor 104 for heat exchange and condensation.

[0031] Meanwhile, the heavy component formed after the distillation separation of the material in the first rectifying tower 101 is pumped out by the first tower bottom pump 103 and sent to the second rectifying tower 201 for heavy component removal distillation, and is again distillation separated into a heavy component and a light component. The light component in the second rectifying tower 201 is heated and evaporated into a gas phase by the second coupling reboiler 202 and the second steam reboiler 203, and is sent to the first coupling reboiler 102 from the top of the second rectifying tower 201 for condensation. The heavy component in the first rectifying tower 101 is equivalent to the material to be distilled after being sent to the second rectifying tower 201, and the heavy component and the light component are reformed after being distilled in the second rectifying tower 201.

[0032] Further, the second rectifying tower 201, the second coupling reboiler 202 and the second steam reboiler 203 are connected with the second tower bottom pump 204, which can collect and discharge the heavy component reformed in the second rectifying tower 201.

[0033] The second coupling reboiler 202 and the second steam reboiler 203 connected with the second rectifying tower 201 can provide sufficient heat for smooth distillation during equipment operation. When the light component in the gas phase of the first rectifying tower 101 enters the second coupling reboiler 202, the light component in the gas phase can provide heat to heat the liquid phase in the second rectifying tower 201, thereby saving steam consumption.

[0034] Meanwhile, the light component in the gas phase of the second rectifying tower 201 enters the first coupling reboiler 102, and the light component in the gas phase can provide heat to heat the liquid phase in the first rectifying tower 101, thereby further saving steam consumption.

[0035] The first rectifying tower 101 and the second rectifying tower 201 are coupled together and used as a whole, which requires additional energy input, i.e. external steam is input into the second steam reboiler 203 to provide heat energy. The functions of the first coupling reboiler 102 and the second coupling reboiler 202 are to use the heat energy inside the first rectifying tower 101 and the second rectifying tower 201, i.e. the heat of the material to be condensed inside the first rectifying tower 101 and the second rectifying tower 201, for coupled heat exchange, thereby reducing the steam consumption in the second steam reboiler 203 and saving the consumption of heat medium.

[0036] Example 2, refer to Figure 2For the second embodiment of the present application, which is different from the first embodiment, a condensing unit 300 is further included, which comprises a first condensing assembly 301 connected with the second coupled reboiler 202, a second condensing assembly 302 connected with the first coupled reboiler 102, and a reflux assembly 303 connected with the first condensing assembly 301 and the second condensing assembly 302.

[0037] The light components in the gas phase in the first rectifying tower 101 enter the second coupled reboiler 202 to be heat-exchanged and condensed, and then are sent to the first condensing assembly 301 to continue heat-exchange and temperature reduction, and finally the uncondensed components such as nitrogen and hydrogen are vented and discharged, and the condensed liquid-phase materials enter the reflux assembly 303 for collection.

[0038] The light components in the gas phase in the second rectifying tower 201 enter the first coupled reboiler 102 to be heat-exchanged and condensed, and then are sent to the second condensing assembly 302 to continue heat-exchange and temperature reduction, and finally the uncondensed components such as nitrogen and hydrogen are vented and discharged, and the condensed liquid-phase materials enter the reflux assembly 303 for collection.

[0039] The reflux assembly 303 comprises a second reflux tank 303a and a second overhead reflux pump 303b connected with the second reflux tank 303a; the first condensing assembly 301 and the second condensing assembly 302 are connected with the second reflux tank 303a; the other end of the second overhead reflux pump 303b is connected with the second rectifying tower 201 and the second reflux tank 303a, and a production pipeline 303c is arranged between the second overhead reflux pump 303b and the second rectifying tower 201.

[0040] The liquid-phase materials condensed by the first condensing assembly 301 and the second condensing assembly 302 enter the reflux assembly 303 and are collected by the second reflux tank 303a, and then the collected materials are pumped into the second rectifying tower 201 by the second overhead reflux pump 303b, part of the materials flows back to the second reflux tank 303a, and part of the materials can be collected as products by the production pipeline 303c and delivered to the downstream process.

[0041] The second overhead reflux pump 303b is connected with the second reflux tank 303a, so that there is a minimum reflux flow in the second reflux tank 303a, avoiding low-load operation of the equipment.

[0042] Further, the first condensing assembly 301 comprises a first condenser 301a, a second condenser 301b and a third condenser 301c arranged in series, and the second coupled reboiler 202 is connected with the first condenser 301a.

[0043] The first condenser 301a, the second condenser 301b and the third condenser 301c are connected with the second reflux tank 303a of the reflux assembly 303.

[0044] The light components of the gas phase in the first rectifying column 101 are sequentially condensed by heat exchange in the first condenser 301a, the second condenser 301b and the third condenser 301c, wherein the components such as nitrogen and hydrogen that are not condensed are discharged from the third condenser 301c, and the liquid phases condensed by the first condenser 301a, the second condenser 301b and the third condenser 301c are respectively introduced into the second reflux tank 303a connected therewith.

[0045] The second condensing assembly 302 comprises the fourth condenser 302a and the fifth condenser 302b arranged in series, the first coupling reboiler 102 is connected with the fourth condenser 302a, and the fourth condenser 302a and the fifth condenser 302b are connected with the second reflux tank 303a of the reflux assembly 303.

[0046] The light component content in the second rectifying column 201 is small after rectification through the first rectifying column 101, and in order to reduce the waste of materials, the condensation is completed through the fourth condenser 302a and the fifth condenser 302b at this time, and only one fourth condenser 302a can also complete most of the condensation of light components, but a little waste may occur in the early stage of material rectification.

[0047] The light components of the gas phase in the second rectifying column 201 are sequentially condensed by heat exchange in the fourth condenser 302a and the fifth condenser 302b, wherein the components such as nitrogen and hydrogen that are not condensed are discharged from the fifth condenser 302b, and the liquid phases condensed by the fourth condenser 302a and the fifth condenser 302b are respectively introduced into the second reflux tank 303a connected therewith.

[0048] The remaining structure is the same as that of Example 1.

[0049] Example 3, with reference to Figure 3 This is the third embodiment of the present application, which is different from the second embodiment in that the reflux assembly 303 comprises the second reflux tank 303a and the first reflux tank 303d, the second overhead reflux pump 303b connected with the second reflux tank 303a, and the first overhead reflux pump 303e connected with the first reflux tank 303d.

[0050] The first condensing assembly 301 is connected with the first reflux tank 303d, and the second condensing assembly 302 is connected with the second reflux tank 303a.

[0051] The other end of the second overhead reflux pump 303b is connected with the second rectifying column 201 and the second reflux tank 303a, the first overhead reflux pump 303e is connected with the first rectifying column 101 and the first reflux tank 303d, and the pipeline 303c is arranged between the second overhead reflux pump 303b and the second rectifying column 201.

[0052] The first reflux tank 303d is connected with the first condenser 301a, the second condenser 301b and the third condenser 301c in the first condensing assembly 301, and the liquid phase condensed by the first condenser 301a, the second condenser 301b and the third condenser 301c respectively enters the first reflux tank 303d, and the material in the first reflux tank 303d is sent into the first rectifying column 101 through the first overhead reflux pump 303e, and meanwhile part of the material refluxes into the first reflux tank 303d.

[0053] The second reflux tank 303a is connected with the fourth condenser 302a and the fifth condenser 302b of the second condensing assembly 302, and the liquid phase condensed by the fourth condenser 302a and the fifth condenser 302b respectively enters the second reflux tank 303a, and the material in the second reflux tank 303a is sent into the second rectifying column 201 through the second overhead reflux pump 303b, and meanwhile part of the material refluxes into the second reflux tank 303a.

[0054] Meanwhile, the material in the second reflux tank 303a can be collected through the production pipeline 303c and transported to the downstream process as a product.

[0055] The remaining structure is the same as that of Example 2.

[0056] Example 4, with reference to Figure 1 The third embodiment of the present application provides a chlorosilane coupled rectification method based on heat pump rectification, which comprises the following steps: chlorosilane material enters the first rectifying column 101 to perform light component rectification to form light components and heavy components, wherein the pressure of the first rectifying column 101 is controlled at 0.12-0.14 MPa.

[0057] The light components are heated and evaporated by the first coupled reboiler 102, enter the second coupled reboiler 202 after being heated and pressurized by the compressor 104, and are condensed, and when the light components enter the second coupled reboiler 202 to exchange heat, the steam consumption of the second coupled reboiler 202 can be reduced, wherein the outlet pressure of the compressor 104 is controlled at 0.7-0.8 MPa.

[0058] The heavy components are sent into the second rectifying column 201 to perform heavy component rectification to form light components and heavy components again; wherein the pressure of the second rectifying column 201 is controlled at 0.38-0.40 MPa.

[0059] The light components are evaporated from liquid phase to gas phase through the second coupled reboiler 202 and the second steam reboiler 203, and enter the first coupled reboiler 102 from the gas phase at the top of the second rectifying column 201 to be condensed, and when the light components enter the first coupled reboiler 102 to exchange heat, the steam consumption of the first coupled reboiler 102 can be reduced.

[0060] The condensed light components in the second coupling reboiler 202 enter the first condensing assembly 301 for heat exchange, the heat-exchanged gas is discharged, and the liquid is recovered through the reflux assembly 303.

[0061] The condensed gas phase in the first coupling reboiler 102 enters the second condensing assembly 302 for heat exchange, the heat-exchanged gas is discharged, and the liquid is recovered through the reflux assembly 303.

[0062] Further, the reflux assembly 303 includes a second reflux tank 303a and a first reflux tank 303d; the liquid in the first condensing assembly 301 is recovered by the first reflux tank 303d, and the liquid in the second condensing assembly 302 is recovered by the second reflux tank 303a.

[0063] The first condensing assembly 301 includes a first condenser 301a, a second condenser 301b and a third condenser 301c arranged in series, the light components of the first rectifying tower 101 are pressurized and heated by the compressor 104, the pressure is between 0.7-0.8 MPa, and the temperature is between 108-113℃, after heat exchange through the second coupling reboiler 202, the light components are condensed again through the first condenser 301a, the second condenser 301b and the third condenser 301c, the media used by the three heat exchangers are, in turn, circulating water, seven-degree water or ethylene glycol, or-20℃, or-40℃ refrigerant for condensation; the chlorosilane is condensed in a multi-stage condensation manner, ensuring the recycling of all chlorosilane materials, reducing the amount of venting, and the condensed liquid enters the first reflux tank 303d, and is transported to the first rectifying tower 101 through the second overhead pump in the first reflux tank 303d.

[0064] The second condensing assembly 302 includes a fourth condenser 302a and a fifth condenser 302b arranged in series, the temperature of the light components of the second rectifying tower 201 is between 85-88℃, after heat exchange through the first coupling reboiler 102, the light components are condensed again through the fourth condenser 302a and the fifth condenser 302b, the media used by the two heat exchangers are circulating water and seven-degree water, the temperature of the circulating water is between 30-35℃, and the temperature of the seven-degree water is 7℃, the condensed liquid enters the second reflux tank 303a, and is transported to the second rectifying tower 201 through the first overhead pump in the second reflux tank 303a, and the other part is taken out as a product.

[0065] The first rectifying tower 101 is used to remove light components with lower boiling point than trichlorosilane, and the second rectifying tower 201 is used to remove heavy components with higher boiling point than trichlorosilane.

[0066] Comparative Example 1, refer to Figure 4 The distillation is carried out by a single rectifying tower.

[0067] The test results of material saving effect are shown in Table 1:

[0068] Table 1

[0069]

[0070] In the table, the coolant represents a medium for cooling, and the heating medium represents a medium for heating or temperature rising. The heating medium is steam, and the coolant is circulating water, seven-degree water, ethylene glycol, -40℃ coolant (R507, etc.).

[0071] Through the rectification method of Example 4, the steam consumption is reduced by about 30% to 50% in total.

[0072] Points for attention during commissioning: 1. The steam needs to be used for heat exchange first, and the first rectification tower 101 is put into use after the second rectification tower 201 gradually operates normally; 2. The compressor 104 is put into use when the gas amount at the top of the first rectification tower 101 is sufficient; 3. The coupling reboiler of the second rectification tower 201 starts to work at the same time when the compressor 104 starts to work, and the use amount of steam is reduced at the same time.

[0073] It should be noted that the above examples are only used to illustrate the technical solutions of the present application and are not limiting. Although the present application has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present application can be modified or replaced equivalently without departing from the spirit and scope of the technical solutions of the present application, and all should be covered in the scope of the claims of the present application.

Claims

1. A chlorosilane coupled distillation apparatus based on heat pump distillation, characterized in that: include, A first distillation unit (100) includes a first distillation column (101), a first coupled reboiler (102) connected to the first distillation column (101), and a first reboiler pump (103) connected to the first distillation column (101) and the first coupled reboiler; and, The second distillation unit (200) includes a second distillation column (201), a second coupled reboiler (202) and a second steam reboiler (203) connected to the second distillation column (201); One end of the first column bottom pump (103) is connected to the second distillation column (201), the top of the first distillation column (101) is connected to the second coupled reboiler (202) via a compressor (104), and the top of the second distillation column (201) is connected to the first coupled reboiler (102); It also includes a condensation unit (300), which includes a first condensation assembly (301) connected to the second coupled reboiler (202), a second condensation assembly (302) connected to the first coupled reboiler (102), and a reflux assembly (303) connected to the first condensation assembly (301) and the second condensation assembly (302).

2. The chlorosilane coupled distillation apparatus based on heat pump distillation according to claim 1, characterized in that: The reflux assembly (303) includes a second reflux tank (303a) and a second top reflux pump (303b) connected to the second reflux tank (303a). The first condensation assembly (301) and the second condensation assembly (302) are connected to the second reflux tank (303a); One end of the second column top reflux pump (303b) is connected to the second distillation column (201) and the second reflux tank (303a); A collection pipe (303c) is provided between the second column top reflux pump (303b) and the second distillation column (201).

3. The chlorosilane coupled distillation apparatus based on heat pump distillation according to claim 1, characterized in that: The reflux assembly (303) includes a second reflux tank (303a) and a first reflux tank (303d), a second top reflux pump (303b) connected to the second reflux tank (303a), and a first top reflux pump (303e) connected to the first reflux tank (303d). The first condensation assembly (301) is connected to the first reflux tank (303d); the second condensation assembly (302) is connected to the second reflux tank (303a). One end of the second top reflux pump (303b) is connected to the second distillation column (201) and the second reflux tank (303a), and the first top reflux pump (303e) is connected to the first distillation column (101) and the first reflux tank (303d); A collection pipe (303c) is provided between the second column top reflux pump (303b) and the second distillation column (201).

4. The chlorosilane coupled distillation apparatus based on heat pump distillation according to any one of claims 1 to 3, characterized in that: The first condensation assembly (301) includes a first condenser (301a), a second condenser (301b), and a third condenser (301c) arranged in series. The second coupled reboiler (202) is connected to the first condenser (301a); The first condenser (301a), the second condenser (301b) and the third condenser (301c) are connected to the reflux assembly (303).

5. The chlorosilane coupled distillation apparatus based on heat pump distillation according to claim 4, characterized in that: The second condensing assembly (302) includes a fourth condenser (302a) and a fifth condenser (302b) arranged in series. The first coupled reboiler (102) is connected to the fourth condenser (302a); The fourth condenser (302a) and the fifth condenser (302b) are connected to the reflux assembly (303).

6. The chlorosilane coupled distillation apparatus based on heat pump distillation according to any one of claims 1-3 and 5, characterized in that: The second distillation column (201), the second coupled reboiler (202) and the second steam reboiler (203) are connected to a second bottom pump (204).

7. A chlorosilane coupled distillation method based on heat pump distillation, characterized in that: The chlorosilane coupled distillation apparatus based on heat pump distillation as described in claim 1 comprises: The chlorosilane material enters the first distillation column (101) for light component removal and distillation to form light and heavy components. The light component is heated and evaporated by the first coupled reboiler (102), and after being heated and pressurized by the compressor (104) from the top of the column, it enters the second coupled reboiler (202) for condensation; The heavy components are collected and sent to the second distillation column (201) for de-heavy distillation to form light components and heavy components again; The light component is evaporated from the liquid phase into a gas phase through the second coupled reboiler (202) and the second steam reboiler (203). The gas phase from the top of the second distillation column (201) enters the first coupled reboiler (102) for condensation.

8. The chlorosilane coupled distillation method based on heat pump distillation according to claim 7, characterized in that: The light components condensed in the second coupled reboiler (202) enter the first condensation assembly (301) for heat exchange. The gas after heat exchange is discharged, and the liquid is recovered through the reflux assembly (303). The condensed gas phase in the first coupled reboiler (102) enters the second condensation assembly (302) for heat exchange. The gas after heat exchange is discharged, and the liquid is recovered through the reflux assembly (303).

9. The chlorosilane coupled distillation method based on heat pump distillation according to claim 8, characterized in that: The reflux assembly (303) includes a second reflux tank (303a) and a first reflux tank (303d). The liquid in the first condensation unit (301) is recovered by the first reflux tank (303d); The liquid in the second condensation unit (302) is recovered by the second reflux tank (303a).

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