A method for the production of silane by means of a reactive dividing wall distillation

Abstract

The application discloses a method for preparing silane by means of a baffle reaction rectifying tower, and belongs to the technical field of silane preparation. Trichlorosilane or dichlorodisilane or a mixture of the two is fed from the top of the lower section of the baffle reaction rectifying tower. The gas phase rising on both sides of the baffle is merged in the common rectifying section above the baffle. The liquid phase descending on both sides of the baffle is merged in the common stripping section at the bottom of the baffle. The liquid phase above the baffle is distributed to both sides of the baffle. The purity of the silane obtained from the top of the tower is greater than 99.99 wt%. The purity of the silicon tetrachloride obtained from the bottom of the tower is greater than 99.9 wt%. The mixture of dichlorodisilane and monochlorotrisilane is taken out from the middle and lower sections of the separation section of the baffle, and is fed into the circulating material feeding port at the top of the upper section of the baffle, so that the raw material conversion rate and the separation efficiency are improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of silane preparation, and particularly relates to a method for preparing silane by using a baffle reaction rectification. BACKGROUND

[0002] Silane, also known as monosilane or hydrogenated silicon, is a colorless and extremely flammable gas with a chemical formula of SiH4. It is easy to purify and can be precisely controlled, and is called "flowing pure silicon". It is the core raw material for preparing high-purity crystalline silicon by a silane method, and is an important electronic special gas that cannot be replaced by other silicon sources. It is widely used in TFT / LCD, crystalline silicon solar cells, semiconductors, and emerging silicon-carbon negative electrodes, advanced ceramics and other fields. Silane is almost used in the entire new energy, semiconductor and new material industry. The preparation methods of silane mainly include magnesium silicide method, sodium aluminum hydride method and chlorosilane disproportionation method. Among them, the chlorosilane disproportionation method is to synthesize trichlorosilane by hydrogenation reaction of silicon tetrachloride, and then to generate silane product through three-step reversible disproportionation reaction of trichlorosilane, and to generate by-product silicon tetrachloride, which returns to the hydrogenation process. The entire system is closed-loop circulation, almost no external discharge, high atomic utilization rate, and is conducive to environmental protection. It is very suitable for industrial production and has become the main method for preparing silane.

[0003] The chlorosilane disproportionation method is developed by the United Carbon Corporation (UCC) of the United States and is proposed in the patent US4340574. The process is to prepare silane by combining multi-step disproportionation reaction with rectification purification through two-stage fixed bed. Due to the limitation of reaction equilibrium, the single-pass yield of silane is less than 8 mol.%, a large amount of material needs to be recycled, the process flow is long, the production efficiency is low, and the energy consumption and investment are large.

[0004] The patent CN103172071B discloses a device and method for preparing high-purity silane by disproportionation reaction rectification of trichlorosilane, which is connected by a reaction rectification process, a silicon tetrachloride absorption process, a fixed bed adsorption process and a product tank filling process. The process flow is complex, and the absorbed silane still contains uncondensed chlorosilane, which affects the subsequent adsorption process and reduces the purity of the product.

[0005] The patent CN106241813B discloses a system and method for producing high-purity silane from trichlorosilane, which includes a reaction tower, a multi-stage condenser, a compressor, a light-removing tower and a product tower. Since the crude silane entering the compressor contains uncondensed dichlorodisilane and monochlorotrisilane, the boiling point difference between the two and silane is large, which is easy to liquefy in the compressor, leading to frequent failures of the compressor, which is extremely detrimental to the safety production of enterprises. SUMMARY

[0006] To solve the above technical problems, the application provides a method for preparing silane by means of a partitioned reaction rectification column, in which trichlorosilane or dichlorodisilane or a mixture thereof is used as raw material to carry out disproportionation reaction and separation in the partitioned reaction rectification column, so that silane with a purity of more than 99.99wt% is obtained from the top of the column, and silicon tetrachloride with a purity of more than 99.9wt% is obtained from the bottom of the column.

[0007] To achieve the above object, the application provides the following technical solutions.

[0008] The application provides a method for preparing silane by means of partitioned reaction rectification, which utilizes the partitioned reaction rectification process coupling reaction rectification and partitioned rectification to prepare silane, so that the raw material conversion rate and separation efficiency are improved.

[0009] Preferably, the method for preparing silane by means of partitioned reaction rectification comprises the following steps.

[0010] Trichlorosilane or dichlorodisilane or a mixture thereof is fed from the top of the lower section of the partitioned reaction rectification column, the ascending gas phase on both sides of the partition is merged in the common rectification section above the partition, the descending liquid phase on both sides of the partition is merged in the common stripping section at the bottom of the partition, and the liquid phase above the partition is distributed to both sides of the partition according to the reaction and separation requirements, with a mass ratio of 1:0.5-1:4; silane with a purity of more than 99.99wt% is obtained from the top of the column, silicon tetrachloride with a purity of more than 99.9wt% is obtained from the bottom of the column, and the mixture of dichlorodisilane and monochlorotrisilane is collected from the middle and lower part of the separation section of the partition and returned to the feeding port at the top of the lower section of the partitioned reaction rectification column.

[0011] In the application, the left side of the partition is divided into a partitioned reaction upper section and a partitioned reaction lower section, the top of the partitioned reaction upper section and the top of the partitioned reaction lower section are respectively separated by end covers, and a partial condenser is arranged between the common rectification section and the top of the partitioned reaction upper section and between the bottom of the partitioned reaction upper section and the top of the partitioned reaction lower section; the middle and lower part of the separation section on the right side of the partition is provided with a side collection port and is connected with the circulating material feeding port at the top of the partitioned reaction upper section; the partitioned reaction rectification device coupling reaction rectification and partitioned rectification is used to prepare high-quality silane, and the silane preparation device is optimized, and the energy consumption is reduced.

[0012] The application further provides a partitioned reaction rectification column system for preparing silane by means of partitioned reaction rectification, wherein the partitioned reaction rectification column comprises a partitioned reaction rectification column, a reboiler, a condenser, a first partial condenser, a second partial condenser and a side collection pump; the reboiler is used for heating silicon tetrachloride separated from the liquid outlet at the bottom of the partitioned reaction rectification column; the condenser is used for condensing silane collected from the top of the partitioned reaction rectification column;

[0013] The vertical partition plate is arranged in the middle of the partition plate reactive rectifying tower, and the partition plate reactive rectifying tower is divided into a common rectifying section, an upper partition plate reactive section, a lower partition plate reactive section, a partition plate separation section and a common stripping section.

[0014] The common rectifying section, the partition plate separation section and the common stripping section are filled with high-efficiency structured packing, trays or structured packing-tray composite separation elements.

[0015] The liquid phase inlet of the reboiler is connected with the tower kettle of the partition plate reactive rectifying tower, the gas phase outlet of the reboiler is connected with the gas phase inlet of the tower kettle, and the liquid phase outlet of the tower kettle is connected with the silicon tetrachloride discharge pipeline.

[0016] The gas phase inlet of the condenser is connected with the overhead gas phase outlet of the partition plate reactive rectifying tower, the liquid phase outlet of the condenser is connected with the tower top reflux port, and the gas phase outlet of the condenser is connected with the silane discharge pipeline.

[0017] The bottom of the common rectifying section is provided with a liquid collection and redistribution device, which is distributed to both sides of the partition plate at a certain ratio; the liquid phase distributed to the upper partition plate reactive section enters through the pipeline connected with the top reflux port of the upper partition plate reactive section through the liquid phase outlet at the bottom of the liquid collection and redistribution device; the liquid phase distributed to the partition plate separation section enters through the pipeline connected with the top reflux port of the partition plate separation section through the liquid phase outlet two at the bottom of the liquid collection and redistribution device, or directly enters through the overflow pipeline of the liquid collection and redistribution device, and the two options can be selected.

[0018] The top and bottom of the upper partition plate reactive section are provided with end covers, the top of the upper partition plate reactive section is provided with a circulating material feeding port, a first partial condenser is arranged between the common rectifying section and the upper partition plate reactive section, the gas phase outlet of the top of the upper partition plate reactive section is connected with the gas phase inlet of the first partial condenser, the liquid phase outlet of the first partial condenser is connected with the reflux port of the top of the upper partition plate reactive section, and the gas phase outlet of the first partial condenser is connected with the gas phase inlet of the bottom of the common rectifying section.

[0019] The top of the lower partition plate reactive section is provided with an end cover, the top of the lower partition plate reactive section is provided with a feeding port, a second partial condenser is arranged between the upper partition plate reactive section and the lower partition plate reactive section, the gas phase outlet of the top of the lower partition plate reactive section is connected with the gas phase inlet of the second partial condenser, the liquid phase outlet of the second partial condenser is connected with the reflux port of the top of the lower partition plate reactive section, the gas phase outlet of the second partial condenser is connected with the gas phase inlet of the bottom of the upper partition plate reactive section, and the liquid phase outlet of the bottom of the upper partition plate reactive section is connected with the reflux port of the top of the lower partition plate reactive section.

[0020] The liquid phase outlet of the middle and lower part of the partition plate separation section is connected with the inlet of the side sampling pump, and the outlet of the side sampling pump is connected with the circulating material feeding port of the top of the upper partition plate reactive section.

[0021] Preferably, the number of theoretical plates of the common rectification section above the partition plate is 3-10.

[0022] Preferably, both the upper partition plate reaction section and the lower partition plate reaction section are filled with structured catalysts, and the bed height of each is 2-10 m. If the bed height is not enough, the conversion rate of the material will be reduced; if the bed height is too high, the excess amount is too large, and the investment is wasted.

[0023] Preferably, the number of theoretical plates of the partition plate separation section is 25-40.

[0024] Preferably, the number of theoretical plates of the common stripping section at the bottom of the partition plate is 10-25.

[0025] Preferably, in the partition plate reaction rectification tower, the reboiler is a thermosyphon reboiler using low-pressure steam or heat-conducting oil as a high-grade heat source; the condenser is a condenser using a coolant with a temperature not higher than -90℃ as a condensing medium; the first partial condenser is a condenser using a coolant with a temperature not higher than 15℃ as a condensing medium; and the second partial condenser is a condenser using circulating water as a condensing medium.

[0026] Preferably, in the partition plate reaction rectification tower, the tower top pressure of the partition plate reaction rectification tower is 0.2-0.4 MPaG, the tower top temperature is -70 to -90℃, and the tower top reflux ratio is (1.0-10)∶1; the temperature of the material controlled by the first partial condenser is 10-40℃; and the temperature of the material controlled by the second partial condenser is 40-70℃. The tower top pressure is adjusted according to the catalyst tolerance temperature, the coolant condition and the heat medium condition; the tower top temperature changes with the tower top pressure; and the reflux ratio, the temperature control of the first partial condenser and the temperature control of the second partial condenser are adjusted according to the purity of the tower top product, the conversion rate of the reaction and the energy consumption.

[0027] Compared with the prior art, the present application has the following advantages and technical effects:

[0028] The present application provides a method for preparing silane by a partition plate reaction rectification tower, which optimizes the previous reaction rectification tower and separation tower device into one partition plate reaction rectification tower by using the partition plate reaction rectification process coupling reaction rectification and partition plate rectification technology, saves the equipment investment by more than 20%, and reduces the energy consumption of the device by 10-30%. BRIEF DESCRIPTION OF DRAWINGS

[0029] The accompanying drawings, which form a part of this application, are included to provide a further understanding of the application and are incorporated in and constitute a part of this application. The embodiments illustrated in the drawings are provided to explain the present application and should not be considered limiting of the present application. In the drawings:

[0030] Figure 1The equipment structure and flow chart for preparing silane by the dividing wall reactive rectification of the present application, wherein: T1, dividing wall reactive rectification column, E1, reboiler, E2, condenser, E3, first partial condenser, E4, second partial condenser, P1, side draw pump; T1-1, common rectification section, T1-2, upper dividing wall reactive section, T1-3, lower dividing wall reactive section, T1-4, dividing wall separation section, T1-5, common stripping section.

[0031] Figure 2 The process flow chart in Comparative Example 1, wherein: T2, reactive rectification column, E5, reactive rectification column reboiler, E6, reactive rectification column condenser, E7, reactive rectification column first partial condenser, E8, reactive rectification column second partial condenser, C1, compressor, T3, silane separation column, E9, silane separation column reboiler, E10, silane separation column condenser, P2, silane separation column bottom pump, T2-1, reactive rectification column rectification section, T2-2, reactive rectification column upper reactive section, T2-3, reactive rectification column lower reactive section, T2-4, reactive rectification column stripping section, T3-1, silane separation column rectification section, T3-2, silane separation column stripping section. DETAILED DESCRIPTION

[0032] The various illustrative embodiments of the present application will now be described in detail below. This detailed description is merely intended to teach a person skilled in the art further details about the various aspects and features of the present application and is not intended to limit the scope of the application. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and the present application.

[0033] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application. In addition, any numerical values recited herein include all values from the lower to the upper value. Ranges of values provided are merely intended to serve as a shorthand method of referring individually to each separate value inclusive of the end points unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. The endpoints of all ranges recited are included as endpoints of the range and includes individual values and sub-ranges within the stated ranges.

[0034] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. Although preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present application. All documents mentioned herein are incorporated by reference to disclose and describe the methods and / or materials in connection with which the documents are cited. In case of conflict between the present specification and any document incorporated by reference, the present specification will control.

[0035] Many modifications and variations to the illustrative embodiments described herein will be apparent to those skilled in the art from consideration of the specification and practice of the subject technology. Additional embodiments of the technology will be apparent to those skilled in the art from consideration of the specification and practice of the subject technology. Each feature disclosed in this specification, and / or the claims, can be provided independently of or in combination with each of the other features.

[0036] As used herein, the terms "comprises", "comprising", "includes", "including", "has", "having" or the like are open-ended expressions that are intended to denote the presence of stated features, integers, steps or the like, but do not preclude the presence or addition of one or more other features, integers, steps, acts, objects, elements or the like.

[0037] The terms "first", "second", "E1", "E2", "E3", "T1-1", "T1-2", "T1-3", "T1-4", "T1-5" and the like are used only to distinguish one element from another, but do not otherwise indicate relative importance of the elements. In addition, the terms "horizontal", "vertical", and the like are used herein to describe the orientation of the components, and do not mean that the components must be absolutely horizontal or absolutely vertical, but can be slightly inclined. For example, "horizontal" only means that the direction is more horizontal than "vertical", and does not mean that the structure must be absolutely horizontal, but can be slightly inclined. The term "vertical" in the present application is perpendicular to the ground direction.

[0038] In the description of the present application, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set", "install", "connect", "connect" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication between the two elements inside. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0039] The raw materials used in the embodiments of the present application are all commercially available.

[0040] The present application provides a method for preparing silane by using a partition reaction rectification tower, and a process flow chart is shown as follows Figure 1 The device for preparing silane comprises a partition reaction rectification tower T1, a reboiler E1, a condenser E2, a first partial condenser E3, a second partial condenser E4 and a side sampling pump P1.

[0041] A vertical partition is arranged in the middle of the partition reaction rectification tower T1, which divides the partition reaction rectification tower T1 into a common rectification section T1-1, an upper partition reaction section T1-2, a lower partition reaction section T1-3, a partition separation section T1-4 and a common rectification section T1-5.

[0042] The liquid phase inlet of the reboiler E1 of the partition reaction rectification tower T1 is connected with the tank, the gas phase outlet of the reboiler E1 is connected with the gas phase inlet of the tank, and the liquid phase outlet of the tank is connected with the silicon tetrachloride discharge pipeline.

[0043] The gas phase inlet of the condenser E2 of the partitioned reaction rectification column T1 is connected with the overhead gas phase outlet, the liquid phase outlet of the condenser E2 is connected with the overhead reflux port, and the gas phase outlet of the condenser E2 is connected with the silane discharge pipeline;

[0044] The bottom of the common rectification section T1-1 of the partitioned reaction rectification column T1 is provided with a liquid collection and redistribution device, and the liquid phase above the partition is distributed to both sides of the partition according to the reaction and separation requirements in a mass ratio of 1:0.5-1:4; the liquid phase distributed to the upper partitioned reaction section T1-2 enters through a pipeline connected with the overhead reflux port of the upper partitioned reaction section T1-2 from the liquid phase outlet at the bottom of the liquid collection and redistribution device; the liquid phase distributed to the partitioned separation section T1-4 enters through a pipeline connected with the overhead reflux port of the partitioned separation section T1-4 from the liquid phase outlet two at the bottom of the liquid collection and redistribution device, or directly enters from the overflow pipeline of the liquid collection and redistribution device, and one of the two is selected;

[0045] The top and bottom of the upper partitioned reaction section T1-2 of the partitioned reaction rectification column T1 are provided with end caps, the top of the upper partitioned reaction section T1-2 is provided with a circulating material feed port, a first partial condenser E3 is arranged between the common rectification section T1-1 and the upper partitioned reaction section T1-2, the gas phase outlet at the top of the upper partitioned reaction section T1-2 is connected with the gas phase inlet of the first partial condenser E3, the liquid phase outlet of the first partial condenser E3 is connected with the reflux port at the top of the upper partitioned reaction section T1-2, and the gas phase outlet of the first partial condenser E3 is connected with the gas phase inlet at the bottom of the common rectification section T1-1;

[0046] The top of the lower partitioned reaction section T1-3 of the partitioned reaction rectification column T1 is provided with an end cap, the top of the lower partitioned reaction section T1-3 is provided with a feed port, a second partial condenser E4 is arranged between the upper partitioned reaction section T1-2 and the lower partitioned reaction section T1-3, the gas phase outlet at the top of the lower partitioned reaction section T1-3 is connected with the gas phase inlet of the second partial condenser E4, the liquid phase outlet of the second partial condenser E4 is connected with the reflux port at the top of the lower partitioned reaction section T1-3, and the gas phase outlet of the second partial condenser E4 is connected with the gas phase inlet at the bottom of the upper partitioned reaction section T1-2; the liquid phase outlet at the bottom of the upper partitioned reaction section T1-2 is connected with the reflux port at the top of the lower partitioned reaction section T1-3;

[0047] The liquid phase outlet in the middle and lower part of the partitioned separation section T1-4 of the partitioned reaction rectification column T1 is connected with the inlet of the side draw pump P1, and the outlet of the side draw pump P1 is connected with the circulating material feed port at the top of the upper partitioned reaction section T1-2.

[0048] In some embodiments of the present application, both the upper section T1-2 and the lower section T1-3 of the baffle reaction section are filled with structured catalysts, and the bed height is 2-10 m. The common rectification section T1-1, the baffle separation section T1-4 and the common stripping section T1-5 are filled with high-efficiency regular packing, tray or regular packing-tray composite separation elements. The theoretical plate number of the common rectification section T1-1 is 3-10, the theoretical plate number of the baffle separation section T1-4 is 25-40, and the theoretical plate number of the common stripping section T1-5 is 10-25. The baffle in the baffle reaction rectification tower T1 can be centrally arranged or eccentrically arranged, and is determined according to the raw material composition and separation index calculation.

[0049] In some embodiments of the present application, the reboiler E1 is a thermosyphon reboiler using low-pressure steam or heat-conducting oil as a high-grade heat source. The condenser E2 is a condenser using a coolant with a temperature not higher than -90℃ as a condensing medium. The first sub-condenser E3 is a condenser using a coolant with a temperature not higher than 15℃ as a condensing medium. The second sub-condenser E4 is a condenser using circulating water as a condensing medium. The tower top pressure of the baffle reaction rectification tower T1 is 0.2-0.4 MPaG, the tower top temperature is -70 to -90℃, and the tower top reflux ratio is (1.0-10) : 1. The material temperature controlled by the first sub-condenser E3 is 10-40℃. The material temperature controlled by the second sub-condenser E4 is 40-70℃.

[0050] The technical solutions of the present application are further illustrated by the following examples.

[0051] Example 1

[0052] The calculation and illustration are performed for a high-purity silane preparation project with a trichlorosilane treatment capacity of 3200 kg / h.

[0053] According to the process flow Figure 1 of the present application, a baffle reaction rectification technology is used to prepare silane. The device for preparing silane by the baffle reaction rectification technology includes a baffle reaction rectification tower T1, a reboiler E1 (which is a thermosyphon reboiler using saturated steam at 0.3 MPaG as a heat source), a condenser E2 (which is a condenser using nitrogen gas at -90℃ as a condensing medium), a first sub-condenser E3 (which is a condenser using frozen brine at -5℃ as a condensing medium), a second sub-condenser E4 (which is a condenser using circulating water as a condensing medium) and a side draw pump P1. The tower top pressure of the baffle reaction rectification tower T1 is 0.32 MPaG, the tower top temperature is -64.5℃, and the tower top reflux ratio is 4:1. The material temperature controlled by the first sub-condenser E3 is 18.2℃. The material temperature controlled by the second sub-condenser E4 is 68.8℃.

[0054] The middle part of the said partitioned reactive rectifying column T1 is provided with a vertical partition plate, which divides the column T1 into a common rectifying section T1-1, an upper partitioned reactive section T1-2, a lower partitioned reactive section T1-3, a partitioned separation section T1-4 and a common stripping section T1-5. The upper and lower partitioned reactive sections T1-2 and T1-3 are both filled with structured catalysts, and the bed height of each section is 8 m. The common rectifying section T1-1, the partitioned separation section T1-4 and the common stripping section T1-5 are filled with separation elements of structured packing-tray combination. The theoretical plate number of the common rectifying section T1-1 is 5, the theoretical plate number of the partitioned separation section T1-4 is 35, and the theoretical plate number of the common stripping section T1-5 is 18.

[0055] The liquid phase inlet of the reboiler E1 of the said partitioned reactive rectifying column T1 is connected with the column kettle, the gas phase outlet of the reboiler E1 is connected with the gas phase inlet of the column kettle, and the liquid phase outlet of the column kettle is connected with the silicon tetrachloride discharge pipeline.

[0056] The gas phase inlet of the condenser E2 of the said partitioned reactive rectifying column T1 is connected with the overhead gas phase outlet, the liquid phase outlet of the condenser E2 is connected with the column kettle reflux inlet, and the gas phase outlet of the condenser E2 is connected with the silane discharge pipeline.

[0057] The bottom part of the common rectifying section T1-1 of the said partitioned reactive rectifying column T1 is provided with a liquid collection and redistribution device, which distributes the liquid to both sides of the partition plate in a ratio of 1:1.8. The liquid phase distributed to the upper partitioned reactive section T1-2 enters through the pipeline connected with the top reflux inlet of the upper partitioned reactive section T1-2 via the liquid phase outlet at the bottom part of the liquid collection and redistribution device. The liquid phase distributed to the partitioned separation section T1-4 enters through the pipeline connected with the top reflux inlet of the partitioned separation section T1-4 via the liquid phase outlet two at the bottom part of the liquid collection and redistribution device.

[0058] The top and bottom parts of the upper partitioned reactive section T1-2 of the said partitioned reactive rectifying column T1 are provided with end caps. The top part of the upper partitioned reactive section T1-2 is provided with a circulating material feeding port. A first partial condenser E3 is arranged between the common rectifying section T1-1 and the upper partitioned reactive section T1-2. The gas phase outlet of the top part of the upper partitioned reactive section T1-2 is connected with the gas phase inlet of the first partial condenser E3. The liquid phase outlet of the first partial condenser E3 is connected with the reflux inlet of the top part of the upper partitioned reactive section T1-2. The gas phase outlet of the first partial condenser E3 is connected with the gas phase inlet of the bottom part of the common rectifying section T1-1.

[0059] The top of the baffle reaction lower section T1-3 of the baffle reaction rectifying column T1 is provided with a head, the top of the baffle reaction lower section T1-3 is provided with a feed inlet, a second partial condenser E4 is arranged between the baffle reaction upper section T1-2 and the baffle reaction lower section T1-3, the gas phase outlet at the top of the baffle reaction lower section T1-3 is connected with the gas phase inlet of the second partial condenser E4, the liquid phase outlet of the second partial condenser E4 is connected with the reflux inlet at the top of the baffle reaction lower section T1-3, and the gas phase outlet of the second partial condenser E4 is connected with the gas phase inlet at the bottom of the baffle reaction upper section T1-2; the liquid phase outlet at the bottom of the baffle reaction upper section T1-2 is connected with the reflux inlet at the top of the baffle reaction lower section T1-3.

[0060] The liquid phase outlet of the middle and lower part of the baffle separation section T1-4 of the baffle reaction rectifying column T1 is connected with the inlet of the side draw pump P1, and the outlet of the side draw pump P1 is connected with the circulating material feed inlet at the top of the baffle reaction upper section T1-2.

[0061] Trichlorosilane with a purity of 100% and a temperature of 80°C is fed into the raw material feed inlet at the top of the baffle reaction lower section T1-3 at a mass flow rate of 3200 kg / h, and according to the above-mentioned appropriate column structure and optimized operating conditions, silane products with a purity of greater than 99.99% and a mass flow rate of 189.5 kg / h are obtained from the top of the column, and silicon tetrachloride with a purity of greater than 99.9% and a mass flow rate of 3010.5 kg / h is obtained from the column bottom. The calculation results are as follows:

[0062] The heating capacity of the reboiler E1 is 847.6 kw;

[0063] The energy consumption of the condenser E2 is -71.7 kw, the energy consumption of the first partial condenser E3 is -278.5 kw, the energy consumption of the second partial condenser E4 is -407.6 kw, and the total cold load is -757.8 kw.

[0064] Comparative Example 1

[0065] According to the process flow of Figure 2 , silane is prepared by using conventional reaction rectification technology, and the device for preparing silane by using conventional reaction rectification technology includes a reaction rectifying column T2, a reboiler E5 (which is a thermosyphon reboiler using saturated steam at 0.3 MPaG as a heat source) of the reaction rectifying column, a condenser E6 (which is a condenser using nitrogen gas at -90°C as a condensing medium) of the reaction rectifying column, a first partial condenser E7 (which is a condenser using frozen brine at -5°C as a condensing medium) of the reaction rectifying column, a second partial condenser E8 (which is a condenser using circulating water as a condensing medium) of the reaction rectifying column, a compressor C1, a silane separation column T3, a reboiler E9 (which is a thermosyphon reboiler using saturated steam at 0.3 MPaG as a heat source) of the silane separation column, a condenser E10 (which is a condenser using nitrogen gas at -90°C as a condensing medium) of the silane separation column, and a column bottom pump P2 of the silane separation column.

[0066] The overhead pressure of the reaction rectification column T1 is 0.32 MPaG, the overhead temperature is -64.5℃, and the overhead reflux ratio is 0.75:1; the material temperature controlled by the first partial condenser E7 of the reaction rectification column is 38℃; the material temperature controlled by the second partial condenser E8 of the reaction rectification column is 78℃; the pressure of the compressor is increased by 0.2 MPa; the overhead pressure of the silane separation column is 0.32 MPaG, the overhead temperature is -82.4℃, and the overhead reflux ratio is 2.9:1.

[0067] The reaction rectification column T2 is divided into a rectification section T2-1, an upper reaction section T2-2, a lower reaction section T2-3, and a stripping section T2-4; the upper reaction section T2-2 and the lower reaction section T2-3 are both filled with structured catalysts, and the bed height of each is 8 m; the common rectification section T2-1 and the common stripping section T2-4 are filled with separation elements in the form of structured packing-tray combinations; the theoretical plate number of the common rectification section T2-1 is 8, and the theoretical plate number of the common stripping section T2-4 is 20;

[0068] The silane separation column T3 is divided into a rectification section T3-1 and a stripping section T3-2; the theoretical plate number of the rectification section T3-1 is 10, and the theoretical plate number of the stripping section T3-2 is 20;

[0069] The liquid phase inlet of the reboiler E5 of the reaction rectification column T2 is connected to the column sump, the gas phase outlet of the reboiler E5 is connected to the gas phase inlet of the column sump, and the liquid phase outlet of the column sump is connected to the silicon tetrachloride discharge line;

[0070] The gas phase inlet of the condenser E6 of the reaction rectification column T2 is connected to the overhead gas phase outlet, the liquid phase outlet of the condenser E6 is connected to the overhead reflux inlet, the gas phase outlet of the condenser E6 is connected to the gas phase inlet of the compressor C1, and the gas phase outlet of the compressor C1 is connected to the silane separation column T3 inlet;

[0071] The bottom of the common rectification section T2-1 of the reaction rectification column T2 is provided with a liquid collector, and the liquid phase outlet at the bottom of the liquid collector is connected to a pipe leading to the reflux inlet at the top of the upper reaction section T2-2;

[0072] The top and bottom of the upper reaction section T2-2 of the reaction rectification column T2 are provided with end caps, the top of the upper reaction section T2-2 is provided with a circulating material inlet, the first partial condenser E7 of the reaction rectification column is arranged between the common rectification section T2-1 and the upper reaction section T2-2, the gas phase outlet of the top of the upper reaction section T2-2 is connected to the gas phase inlet of the first partial condenser E7 of the reaction rectification column, the liquid phase outlet of the first partial condenser E7 of the reaction rectification column is connected to the reflux inlet of the top of the upper reaction section T2-2, and the gas phase outlet of the first partial condenser E7 of the reaction rectification column is connected to the gas phase inlet at the bottom of the common rectification section T2-1;

[0073] The top of the reaction lower section T2-3 of the reaction rectification column T2 is provided with a head, the top of the reaction lower section T2-3 is provided with a feed inlet, a second reaction rectification column condenser E8 is arranged between the reaction upper section T2-2 and the reaction lower section T2-3, the gas phase outlet at the top of the reaction lower section T2-3 is connected with the gas phase inlet of the second reaction rectification column condenser E8, the liquid phase outlet of the second reaction rectification column condenser E8 is connected with the reflux inlet at the top of the reaction lower section T2-3, and the gas phase outlet of the second reaction rectification column condenser E8 is connected with the gas phase inlet at the bottom of the reaction upper section T2-2; the liquid phase outlet at the bottom of the reaction upper section T2-2 is connected with the reflux inlet at the top of the reaction lower section T2-3;

[0074] The liquid phase inlet of the reboiler E9 of the silane separation column T3 is connected with the column bottom, the gas phase outlet of the reboiler E9 is connected with the gas phase inlet of the column bottom, the liquid phase outlet of the column bottom is connected with the inlet of the column bottom pump P2 of the silane separation column, and the outlet of the column bottom pump P2 is connected with the circulating material feed inlet at the top of the reaction upper section T2-2 of the reaction rectification column T2;

[0075] The gas phase inlet of the condenser E10 of the silane separation column T3 is connected with the overhead gas phase outlet, the liquid phase outlet of the condenser E10 is connected with the overhead reflux inlet, and the gas phase outlet of the condenser E10 is connected with the silane discharge pipeline.

[0076] Trichlorosilane with a purity of 100% and a temperature of 80°C is fed from the reaction section of the reaction rectification column T2 at a mass flow rate of 3200 kg / h, and the material taken from the top of the reaction rectification column T2 is introduced into the middle of the separation column T3; the silicon tetrachloride is taken from the column bottom of the reaction rectification column T2. The silane product is taken from the top of the separation column T3, and the material taken from the column bottom of the separation column T3 is returned to the upper part of the reaction section of the reaction rectification column T2. By using the above-mentioned suitable column structure and optimized operating conditions, the product quality meets the standards. The calculation results are as follows:

[0077] The heating amount of the reboiler of the reaction rectification column T2 is 1100.9 kw, the heating amount of the reboiler of the separation column T3 is 31.0 kw, and the total heat load is 1131.9 kw.

[0078] The energy consumption of the condenser of the reaction rectification column T2 is -23.9 kw, the energy consumption of the first condenser of the reaction rectification column T2 is -410.2 kw, the energy consumption of the second condenser of the reaction rectification column T2 is -556.1 kw, the energy consumption of the condenser of the separation column T3 is -51.9 kw, and the total cold load is -1042.1 kw.

[0079] The energy consumption comparison of Example 1 and Comparative Example 1 is shown in Table 1:

[0080] Table 1 Energy consumption comparison of Example 1 and Comparative Example 1

[0081] Comparative Example Example 1 Comparative Example 1 Energy saving value Energy saving ratio Heat load (kw) 847.6 1131.9 284.3 25.12％ Cooling load (kw) 757.8 1042.1 284.3 27.28％

[0082] Example 2

[0083] The accounting instruction is prepared in the high purity silane preparation project with the dichlorodihydrogen silicon treatment amount of 4110 kg / h.

[0084] According to the process flow of Figure 1 The silane is prepared by the method of the dividing wall reactive distillation, the device for preparing the silane by the method of the dividing wall reactive distillation includes the dividing wall reactive distillation column T1, the reboiler E1 (which is the thermosyphon reboiler with the saturated steam at 0.3 MPaG as the heat source), the condenser E2 (which is the condenser with the nitrogen gas at -90℃ as the condensing medium), the first partial condenser E3 (which is the condenser with the frozen brine at -5℃ as the condensing medium), the second partial condenser E4 (which is the condenser with the circulating water as the condensing medium) and the side draw pump P1, the top pressure of the dividing wall reactive distillation column T1 is 0.32 MPaG, the top temperature is -64.5℃, the top reflux ratio is 2.22:1; the material temperature controlled by the first partial condenser E3 is 34.5℃; the material temperature controlled by the second partial condenser E4 is 65.5℃;

[0085] The middle part of the dividing wall reactive distillation column T1 is provided with a vertical dividing wall, which divides the dividing wall reactive distillation column T1 into the common rectification section T1-1, the upper dividing wall reactive section T1-2, the lower dividing wall reactive section T1-3, the dividing wall separation section T1-4 and the common stripping section T1-5, the upper dividing wall reactive section T1-2 is filled with the structured catalyst, the bed height is 8 m, the lower dividing wall reactive section T1-3 is filled with the structured catalyst, the bed height is 3 m, the common rectification section T1-1, the dividing wall separation section T1-4 and the common stripping section T1-5 are filled with the separation element of the regular packing-tray combination, the theoretical plate number of the common rectification section T1-1 is 5, the theoretical plate number of the dividing wall separation section T1-4 is 35, the theoretical plate number of the common stripping section T1-5 is 18;

[0086] The liquid phase inlet of the reboiler E1 of the dividing wall reactive distillation T1 is connected with the column cauldron, the gas phase outlet of the reboiler E1 is connected with the gas phase inlet of the column cauldron, the liquid phase outlet of the column cauldron is connected with the silicon tetrachloride discharge pipeline;

[0087] The gas phase inlet of the condenser E2 of the dividing wall reactive distillation T1 is connected with the top gas phase outlet, the liquid phase outlet of the condenser E2 is connected with the top reflux port, the gas phase outlet of the condenser E2 is connected with the silane discharge pipeline;

[0088] The bottom of the common rectifying section T1-1 of the partitioned reaction rectifying column T1 is provided with a liquid collection and redistribution device, which distributes the liquid to both sides of the partition in a ratio of 1:1; the liquid phase distributed to the upper partitioned reaction section T1-2 enters the pipeline connected to the reflux inlet at the top of the upper partitioned reaction section T1-2 through the liquid phase outlet at the bottom of the liquid collection and redistribution device; the liquid phase distributed to the partitioned separation section T1-4 enters the pipeline connected to the reflux inlet at the top of the partitioned separation section T1-4 through the second liquid phase outlet at the bottom of the liquid collection and redistribution device;

[0089] The top and bottom of the upper partitioned reaction section T1-2 of the partitioned reaction rectifying column T1 are provided with end caps, the top of the upper partitioned reaction section T1-2 is provided with a circulating material feed inlet, a first condenser E3 is arranged between the common rectifying section T1-1 and the upper partitioned reaction section T1-2, the gas phase outlet at the top of the upper partitioned reaction section T1-2 is connected to the gas phase inlet of the first condenser E3, the liquid phase outlet of the first condenser E3 is connected to the reflux inlet at the top of the upper partitioned reaction section T1-2, and the gas phase outlet of the first condenser E3 is connected to the gas phase inlet at the bottom of the common rectifying section T1-1;

[0090] The top of the lower partitioned reaction section T1-3 of the partitioned reaction rectifying column T1 is provided with an end cap, the top of the lower partitioned reaction section T1-3 is provided with a feed inlet, a second condenser E4 is arranged between the upper partitioned reaction section T1-2 and the lower partitioned reaction section T1-3, the gas phase outlet at the top of the lower partitioned reaction section T1-3 is connected to the gas phase inlet of the second condenser E4, the liquid phase outlet of the second condenser E4 is connected to the reflux inlet at the top of the lower partitioned reaction section T1-3, and the gas phase outlet of the second condenser E4 is connected to the gas phase inlet at the bottom of the upper partitioned reaction section T1-2; the liquid phase outlet at the bottom of the upper partitioned reaction section T1-2 is connected to the reflux inlet at the top of the lower partitioned reaction section T1-3;

[0091] The liquid phase outlet in the middle and lower part of the partitioned separation section T1-4 of the partitioned reaction rectifying column T1 is connected to the inlet of a side draw pump P1, the outlet of the side draw pump P1 is connected to the circulating material feed inlet at the top of the upper partitioned reaction section T1-2.

[0092] Dichlorodihydrogen silicon with a purity of 100% and a temperature of 75°C is fed into the raw material feed inlet at the top of the lower partitioned reaction section T1-3 at a mass flow rate of 4110 kg / h, and the above-mentioned suitable column structure and optimized operating conditions are adopted to obtain silane product with a purity of greater than 99.99% and a mass flow rate of 653 kg / h from the top of the column, and silicon tetrachloride with a purity of greater than 99.9% and a mass flow rate of 3457 kg / h from the bottom of the column. The calculation results are as follows:

[0093] The heating capacity of the reboiler E1 is 972.9 kw;

[0094] The energy consumption of the condenser E2 is -136.7 kw, the energy consumption of the first sub-condenser E3 is -625.4 kw, the energy consumption of the second sub-condenser E4 is -66.6 kw, and the total cold load is -828.7 kw.

[0095] Comparative Example 2

[0096] According to the process flow of Figure 2 The conventional reactive distillation technology for preparing silane includes a reactive distillation column T2, a reboiler E5 of the reactive distillation column (which is a thermosyphon reboiler with saturated steam at 0.3 MPaG as heat source), a condenser E6 of the reactive distillation column (which is a condenser with nitrogen gas at -90°C as condensing medium), a first sub-condenser E7 of the reactive distillation column (which is a condenser with refrigerated brine at -5°C as condensing medium), a second sub-condenser E8 of the reactive distillation column (which is a condenser with circulating water as condensing medium), a compressor C1, a silane separation column T3, a reboiler E9 of the silane separation column (which is a thermosyphon reboiler with saturated steam at 0.3 MPaG as heat source), a condenser E10 of the silane separation column (which is a condenser with nitrogen gas at -90°C as condensing medium), and a column bottom pump P2 of the silane separation column.

[0097] The overhead pressure of the reactive distillation column T1 is 0.32 MPaG, the overhead temperature is -64.5°C, and the overhead reflux ratio is 0.62:1; the material temperature controlled by the first sub-condenser E7 of the reactive distillation column is 27°C; the material temperature controlled by the second sub-condenser E8 of the reactive distillation column is 67°C; the pressure increased by the compressor is 0.2 MPa; the overhead pressure of the silane separation column is 0.32 MPaG, the overhead temperature is -82.4°C, and the overhead reflux ratio is 1.2:1.

[0098] The reactive distillation column T2 is divided into a rectifying section T2-1, an upper reactive section T2-2, a lower reactive section T2-3, and a stripping section T2-4; the upper reactive section T2-2 is packed with structured catalyst, and the bed height is 8 m; the lower reactive section T2-3 is packed with structured catalyst, and the bed height is 3 m; the common rectifying section T2-1 and the common stripping section T2-4 are packed with separation elements of regular packing-tray combination; the theoretical plate number of the common rectifying section T2-1 is 8, and the theoretical plate number of the common stripping section T2-4 is 20;

[0099] The silane separation column T3 is divided into a rectifying section T3-1 and a stripping section T3-2; the theoretical plate number of the rectifying section T3-1 is 10, and the theoretical plate number of the stripping section T3-2 is 20;

[0100] The liquid phase inlet of the reboiler E5 of the reactive distillation column T2 is connected with the column bottom; the gas phase outlet of the reboiler E5 is connected with the gas phase inlet of the column bottom; and the liquid phase outlet of the column bottom is connected with the silicon tetrachloride discharge pipeline;

[0101] The gas phase inlet of the condenser E6 of the reaction rectification column T2 is connected with the overhead gas phase outlet, the liquid phase outlet of the condenser E6 is connected with the overhead reflux inlet, and the gas phase outlet of the condenser E6 is connected with the gas phase inlet of the compressor C1, and the gas phase outlet of the compressor C1 is connected with the feeding inlet of the silane separation column T3;

[0102] The bottom of the common rectification section T2-1 of the reaction rectification column T2 is provided with a liquid collector, and the liquid phase outlet at the bottom of the liquid collector is connected with the pipeline entering the overhead reflux inlet of the reaction upper section T2-2;

[0103] The top and bottom of the reaction upper section T2-2 of the reaction rectification column T2 are provided with end caps, the top of the reaction upper section T2-2 is provided with a circulating material feeding inlet, a first partial condenser E7 of the reaction rectification column is arranged between the common rectification section T2-1 and the reaction upper section T2-2, the gas phase outlet at the top of the reaction upper section T2-2 is connected with the gas phase inlet of the first partial condenser E7 of the reaction rectification column, the liquid phase outlet of the first partial condenser E7 of the reaction rectification column is connected with the reflux inlet at the top of the reaction upper section T2-2, and the gas phase outlet of the first partial condenser E7 of the reaction rectification column is connected with the gas phase inlet at the bottom of the common rectification section T2-1;

[0104] The top of the reaction lower section T2-3 of the reaction rectification column T2 is provided with an end cap, the top of the reaction lower section T2-3 is provided with a feeding inlet, a second partial condenser E8 of the reaction rectification column is arranged between the reaction upper section T2-2 and the reaction lower section T2-3, the gas phase outlet at the top of the reaction lower section T2-3 is connected with the gas phase inlet of the second partial condenser E8 of the reaction rectification column, the liquid phase outlet of the second partial condenser E8 of the reaction rectification column is connected with the reflux inlet at the top of the reaction lower section T2-3, and the gas phase outlet of the second partial condenser E8 of the reaction rectification column is connected with the gas phase inlet at the bottom of the reaction upper section T2-2; the liquid phase outlet at the bottom of the reaction upper section T2-2 is connected with the reflux inlet at the top of the reaction lower section T2-3;

[0105] The liquid phase inlet of the reboiler E9 of the silane separation column T3 is connected with the column bottom, the gas phase outlet of the reboiler E9 is connected with the gas phase inlet of the column bottom, the liquid phase outlet of the column bottom is connected with the inlet of the column bottom pump P2 of the silane separation column, and the outlet of the column bottom pump P2 of the silane separation column is connected with the circulating material feeding inlet at the top of the reaction upper section T2-2 of the reaction rectification column T2;

[0106] The gas phase inlet of the condenser E10 of the silane separation column T3 is connected with the overhead gas phase outlet, the liquid phase outlet of the condenser E10 is connected with the overhead reflux inlet, and the gas phase outlet of the condenser E10 is connected with the silane discharge pipeline.

[0107] Dichlorodisilane with purity of 100% and temperature of 75℃ is fed from the appropriate position of the reaction section of the reactive distillation column T2 with mass flow of 4110kg / h, and the material taken out from the top of the reactive distillation column T2 is fed into the middle of the separation column T3; the silicon tetrachloride is taken out from the bottom of the reactive distillation column T2. The silane product is taken out from the top of the separation column T3; the material taken out from the bottom of the separation column T3 is returned to the upper part of the reaction section of the reactive distillation column T2. With appropriate column structure and optimized operating conditions, the product quality meets the standards. The calculation results are as follows:

[0108] The heating amount of the reboiler of the reactive distillation column T2 is 1085.6kw, the heating amount of the reboiler of the separation column T3 is 22.9kw, and the total heat load is 1108.5kw.

[0109] The energy consumption of the condenser of the reactive distillation column T2 is -60.9kw, the energy consumption of the first partial condenser of the reactive distillation column T2 is -363.3kw, the energy consumption of the second partial condenser of the reactive distillation column T2 is -466.9kw, the energy consumption of the condenser of the separation column T3 is -74.0kw, and the total cold load is -965.1kw.

[0110] The energy consumption comparison of Example 2 and Comparative Example 2 is shown in Table 2.

[0111] Table 2 Energy consumption comparison of Example 2 and Comparative Example 2

[0112] Comparative Example Example 2 Comparative Example 2 Energy saving value Energy saving ratio Heat load (kw) 972.9 1108.5 135.6 12.23％ Cooling load (kw) 828.7 965.1 136.4 14.13％

[0113] It can be found from the comparison of Table 1 and Table 2 that, thanks to the baffle reaction distillation process coupling the reaction distillation and the baffle distillation technology, the process presented in the application further saves the energy consumption and the operating cost compared with the two-column process using the conventional reaction distillation, and the equipment investment is less.

[0114] The above is only the preferred specific embodiment of the present application, but the protection scope of the present application is not limited to this, any change or replacement easily thought of by those skilled in the art within the technical range disclosed in the present application should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A method for the preparation of silane by a partitioning reaction rectification, characterized in that, The method comprises the following steps: trichlorosilane or dichlorodisilane or a mixture of both is fed from the top of the lower section of the baffle reaction rectification column, the gas phase rising on both sides of the baffle is merged in the common rectification section above the baffle, the liquid phase descending on both sides of the baffle is merged in the common stripping section at the bottom of the baffle, the liquid phase above the baffle is distributed to both sides of the baffle; silane is obtained from the top of the column, and silicon tetrachloride is obtained from the bottom of the column; a mixture of dichlorodisilane and monochlorotrisilane is taken out from the middle and lower part of the separation section of the baffle, and returned to the circulating material feed port at the top of the upper section of the baffle reaction; the left side of the baffle is divided into an upper section of baffle reaction and a lower section of baffle reaction, the top and bottom of the upper section of baffle reaction and the top of the lower section of baffle reaction are separated by end caps, and a partial condenser is arranged between the common rectification section and the top of the upper section of baffle reaction and between the bottom of the upper section of baffle reaction and the top of the lower section of baffle reaction; a side take-off port is arranged in the middle and lower part of the separation section of the right side of the baffle and connected with the circulating material feed port at the top of the upper section of baffle reaction; a baffle reaction rectification device coupled with reaction rectification and baffle rectification is used to prepare high-quality silane; a first partial condenser is arranged between the common rectification section and the upper section of baffle reaction, and the material temperature controlled by the first partial condenser is 10-40℃; a second partial condenser is arranged between the upper section of baffle reaction and the lower section of baffle reaction, and the material temperature controlled by the second partial condenser is 40-70℃.

2. A dividing wall reactive distillation column system characterized by, The baffle reaction rectification column system for preparing silane by the method for preparing silane by baffle reaction rectification according to claim 1 comprises a baffle reaction rectification column (T1), a reboiler (E1), a condenser (E2), a first partial condenser (E3), a second partial condenser (E4) and a side take-off pump (P1); the reboiler (E1) is used to heat silicon tetrachloride separated from the outlet port of the column sump of the baffle reaction rectification column (T1); the condenser (E2) is used to condense silane collected from the top of the baffle reaction rectification column (T1); a vertical baffle is arranged in the middle of the baffle reaction rectification column (T1), and the baffle reaction rectification column (T1) is divided into a common rectification section (T1-1), an upper section of baffle reaction (T1-2), a lower section of baffle reaction (T1-3), a separation section of baffle (T1-4) and a common stripping section (T1-5); the common rectification section (T1-1), the separation section of baffle (T1-4) and the common stripping section (T1-5) are filled with high-efficiency structured packing, trays or structured packing-tray composite separation elements.

3. The dividing wall reaction rectifier column system of claim 2, wherein, The theoretical plate number of the common rectification section (T1-1) above the baffle is 3-10.

4. The dividing wall reaction rectifier column system according to claim 2, wherein, The upper section of baffle reaction (T1-2) of the baffle reaction rectification column is filled with structural catalyst, and the bed height is 2-10 m; the lower section of baffle reaction (T1-3) is filled with structural catalyst, and the bed height is 2-10 m.

5. The dividing wall reaction rectifier column system according to claim 2, wherein, The theoretical plate number of the separation section of baffle (T1-4) is 25-40.

6. The dividing wall reaction rectifier column system according to claim 2, wherein, The theoretical plate number of the common stripping section (T1-5) at the bottom of the baffle is 10-25.

7. The dividing wall reaction rectifier column system according to claim 2, wherein, The liquid phase inlet of the reboiler (E1) is connected with the column bottom of the divided wall reaction rectification column (T1), the gas phase outlet of the reboiler (E1) is connected with the gas phase inlet of the column top, and the liquid phase outlet of the column bottom is connected with the silicon tetrachloride outlet pipeline; The gas phase inlet of the condenser (E2) is connected with the gas phase outlet of the column top of the divided wall reaction rectification column (T1), the liquid phase outlet of the condenser (E2) is connected with the column top reflux inlet, and the gas phase outlet of the condenser (E2) is connected with the silane outlet pipeline; The bottom of the common rectification section (T1-1) is provided with a liquid collection and redistribution device, which is used to distribute the liquid to both sides of the divided wall according to a certain proportion; the liquid distributed to the upper divided wall reaction section (T1-2) enters the pipeline connected with the column top reflux inlet of the upper divided wall reaction section (T1-2) through the liquid phase outlet at the bottom of the liquid collection and redistribution device; the liquid distributed to the divided wall separation section (T1-4) enters the pipeline connected with the column top reflux inlet of the divided wall separation section (T1-4) through the liquid phase outlet two at the bottom of the liquid collection and redistribution device, or directly enters from the overflow pipeline of the liquid collection and redistribution device, and the two options can be selected. The top and bottom of the upper divided wall reaction section (T1-2) are provided with end covers, the top of the upper divided wall reaction section (T1-2) is provided with a circulating material inlet, a first partial condenser (E3) is arranged between the common rectification section (T1-1) and the upper divided wall reaction section (T1-2), the gas phase outlet of the top of the upper divided wall reaction section (T1-2) is connected with the gas phase inlet of the first partial condenser (E3), the liquid phase outlet of the first partial condenser (E3) is connected with the reflux inlet of the top of the upper divided wall reaction section (T1-2), and the gas phase outlet of the first partial condenser (E3) is connected with the gas phase inlet of the bottom of the common rectification section (T1-1). The top of the lower divided wall reaction section (T1-3) is provided with an end cover, the top of the lower divided wall reaction section (T1-3) is provided with an inlet, a second partial condenser (E4) is arranged between the upper divided wall reaction section (T1-2) and the lower divided wall reaction section (T1-3), the gas phase outlet of the top of the lower divided wall reaction section (T1-3) is connected with the gas phase inlet of the second partial condenser (E4), the liquid phase outlet of the second partial condenser (E4) is connected with the reflux inlet of the top of the lower divided wall reaction section (T1-3), and the gas phase outlet of the second partial condenser (E4) is connected with the gas phase inlet of the bottom of the upper divided wall reaction section (T1-2); the liquid phase outlet of the bottom of the upper divided wall reaction section (T1-2) is connected with the reflux inlet of the top of the lower divided wall reaction section (T1-3). The liquid phase outlet of the middle and lower part of the divided wall separation section (T1-4) is connected with the inlet of the side draw pump (P1), and the outlet of the side draw pump (P1) is connected with the circulating material inlet of the top of the upper divided wall reaction section (T1-2).

8. The dividing wall reaction rectifier column system according to claim 2, wherein, The reboiler (E1) is a thermosyphon reboiler using high-grade heat source; the condenser (E2) is a condenser using a coolant with a temperature of not higher than-90℃ as condensing medium; the first partial condenser (E3) is a condenser using a coolant with a temperature of not higher than 15℃ as condensing medium; and the second partial condenser (E4) is a condenser using circulating water as condensing medium.

9. The dividing wall reaction rectifier column system according to claim 2, wherein, The top pressure of the said partitioned reaction rectifying column (T1) is 0.2-0.4 MPaG, the top temperature is -70--90℃, and the top reflux ratio is (1.0-10)∶1.

Images