Reduction tail gas waste heat utilization system

Abstract

The utility model provides a reduction tail gas waste heat utilization system, and relates to the field of tail gas utilization. A first input pipeline of a waste heat utilization unit is connected with a reduction furnace tail gas output pipeline, and a first output pipeline of the waste heat utilization unit is connected with an input pipeline of a condensation unit; an output pipeline of the condensation unit is divided into two paths which are respectively connected with an input pipeline of the chlorosilane buffer tank and an input pipeline of the compression unit; an output pipeline of the compression unit is connected with a second input pipeline of the waste heat utilization unit; an output pipeline of the chlorosilane buffer tank is connected with an input pipeline of the first analysis unit; an output pipeline of the first analysis unit is connected with the tank area; an input pipeline of the absorption unit is connected with a second output pipeline of the waste heat utilization unit; and an output pipeline of the absorption unit is connected with an input pipeline of the second analysis unit. According to the system, the waste heat of the reduction tail gas can be fully utilized and can be divided into two paths to be independently analyzed, so that the influence of component change of the system on the hydrogen quality is reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to tail gas utilization field, specifically, relate to a kind of reduction tail gas waste heat utilization system. BACKGROUND

[0002] Improved siemens method is the mainstream technology of producing polysilicon internationally, and its core equipment is reduction furnace. The working principle of the reduction furnace is that the mixed gas of trichlorosilane and hydrogen is reacted to generate polysilicon and deposit on the silicon core through the high-temperature silicon core of electric heating. The reactant of the reduction furnace enters the reduction furnace from the bottom plate. The reaction in the furnace is a chemical vapor deposition on the surface with the silicon core as the carrier at about 1050℃. This is a forward reaction. At the same time, there are also many side reactions under high temperature conditions. Different reduction products will be generated at different reaction stages, i.e. high-temperature reduction tail gas.

[0003] After the waste heat utilization system is used, the high-grade waste heat in the high-temperature reduction tail gas is effectively recovered and utilized. However, the low-grade heat source after utilization has not been fully utilized. At the same time, in the production process of polysilicon, the composition of the tail gas of the production equipment, i.e. the reduction furnace, will change with different working conditions, which leads to the fluctuation of the amount of the reduction tail gas with the adjustment of the production operation. In the existing waste heat utilization system, the condensed chlorosilane mixture is mixed with the rich liquid from the absorption tower kettle, and then enters the resolution system. The lean liquid treated by the resolution system will partly re-enter the absorption system as the absorption liquid. Therefore, the change of the composition of the reduction furnace tail gas will directly affect the purity of hydrogen and the efficiency of the resolution system. SUMMARY

[0004] The purpose of the utility model is to provide a reduction tail gas waste heat utilization system, which can effectively recover and utilize the low-grade heat energy in the reduction tail gas, and solve the possible influence of the change of the composition of the reduction tail gas on the absorption and resolution system, thereby improving the resolution efficiency. At the same time, the waste heat utilization is significantly improved, the production cost and energy consumption are effectively reduced, and the energy-saving and emission-reducing goal is achieved.

[0005] To solve the above technical problems, the utility model adopts the following technical scheme:

[0006] A reduction tail gas waste heat utilization system comprises:

[0007] A waste heat utilization unit, a condensing unit, a compression unit, a chlorosilane buffer tank, a first resolution unit, an absorption unit and a second resolution unit;

[0008] The first input pipeline of the waste heat utilization unit is connected with the output pipeline of the reduction furnace tail gas. The first output pipeline of the waste heat utilization unit is connected with the input pipeline of the condensing unit, for sending the reduction tail gas after waste heat utilization into the condensing unit for condensation.

[0009] The output pipeline of the condensing unit is divided into two paths and is connected with the input pipeline of the chlorosilane buffer tank and the input pipeline of the compression unit respectively, for sending the condensed liquid phase into the chlorosilane buffer tank and sending the condensed gas phase into the compression unit;

[0010] The output pipeline of the compression unit is connected with the second input pipeline of the waste heat utilization unit, for sending the compressed gas phase into the waste heat utilization unit for reuse;

[0011] The output pipeline of the chlorosilane buffer tank is connected with the input pipeline of the first resolving unit, for sending the liquid phase chlorosilane into the first resolving unit for resolution;

[0012] The output pipeline of the first resolving unit is connected with the tank area, for sending the resolved liquid into the tank area;

[0013] The input pipeline of the absorption unit is connected with the second output pipeline of the waste heat utilization unit, for sending the gas phase after waste heat utilization into the absorption unit for absorption; the output pipeline of the absorption unit is connected with the input pipeline of the second resolving unit, for sending the material into the second resolving unit for resolution.

[0014] The output pipeline of the second resolving unit is divided into two paths and is connected with the input pipeline of the absorption unit and the tank area respectively, for sending the resolved liquid into the absorption unit and the tank area respectively.

[0015] Further, in the utility model, the condensing unit includes first condenser and second condenser, the input pipeline of first condenser is connected with the first output pipeline of waste heat utilization unit, first condenser divides into two paths and exports to chlorosilane buffer tank and second condenser;Second condenser divides into two paths and exports to chlorosilane buffer tank and compression unit.

[0016] Further, in the utility model, still include resolving column reboiler, the compression unit divides into two paths and exports to the second input pipeline of waste heat utilization unit and the input pipeline of resolving column reboiler;The output pipeline of resolving column reboiler is incorporated into the second output pipeline of waste heat utilization unit and is commonly connected to the input pipeline of absorption unit.

[0017] Further, in the utility model, the first analytic unit includes first analytic tower and first heat exchange unit connected in proper order, the top of first analytic tower is equipped with HCL output pipeline connected with HCL pipeline, the input pipeline of first analytic tower is connected with the output pipeline of chlorosilane buffer tank, the input pipeline of first heat exchange unit is connected with hydrogen output pipeline of absorption unit, first heat exchange unit is divided into two way outputs to tank area and hydrogen pipeline, is used for conveying tank area after heat exchange of analytic liquid of first analytic tower and conveying hydrogen pipeline after heat exchange of hydrogen output of absorption unit.

[0018] Further, in the utility model, the second analytic unit includes a second analytic tower and a second heat exchange unit, the top of the second analytic tower is provided with an HCL output pipeline connected with the HCL pipeline;

[0019] The first input pipeline of the second heat exchange unit is connected with the output pipeline of the absorption unit, the first output pipeline of the second heat exchange unit is connected with the input pipeline of the second analytic tower, for conveying the material discharged by the absorption unit to the second analytic tower after heat exchange for analysis;

[0020] The second input pipeline of the second heat exchange unit is connected with the material output pipeline of the second analytic tower, and the second output pipeline of the second heat exchange unit is divided into two outputs to the absorption unit and the tank area, for conveying the material analyzed by the second analytic tower to the absorption unit and the tank area after heat exchange.

[0021] Further, in the utility model, it further includes third heat exchange unit and fourth heat exchange unit,

[0022] The first input pipeline of the third heat exchange unit is connected with the output pipeline of the chlorosilane buffer tank, and the first output pipeline of the third heat exchange unit is connected with the input pipeline of the first analytic tower, for conveying the liquid phase chlorosilane output by the chlorosilane buffer tank to the first analytic tower after heat exchange for analysis;

[0023] The second input pipeline of the third heat exchange unit is connected with the second output pipeline of the waste heat utilization unit, and the first input pipeline of the fourth heat exchange unit is connected with the second output pipeline of the third heat exchange unit, and the first output pipeline of the second heat exchange unit is output to the absorption unit, for conveying the material after waste heat recycling to the absorption unit after heat exchange.

[0024] Further, in the utility model, the second input pipeline of the fourth heat exchange unit is connected with the hydrogen output pipeline of the absorption unit, and the second output pipeline of the fourth heat exchange unit is output to the first heat exchange unit, for conveying the hydrogen discharged by the absorption unit to the hydrogen pipeline after heat exchange.

[0025] Furthermore, in this invention, the material output pipeline of the second analytical column is also branched off to the reboiler of the analytical column.

[0026] Furthermore, in this invention, the reboiler of the analytical tower also outputs to the heating system.

[0027] This utility model has at least the following advantages or beneficial effects:

[0028] This invention utilizes the high-temperature reduction tail gas by first feeding it into a waste heat utilization unit. The waste heat utilization unit is then connected to a condensation unit to condense the tail gas after waste heat utilization. The condensation unit is connected to a chlorosilane buffer tank and a compression unit, respectively. The condensed gas phase is fed into the compression unit for heating, and the condensed liquid phase is fed into the chlorosilane buffer tank to form liquid chlorosilane. The compression unit is then connected to the waste heat utilization unit again for waste heat utilization. The chlorosilane buffer tank is connected to a first analysis unit to analyze the liquid chlorosilane, and the analyzed liquid is sent to a tank area. The absorption unit's input pipeline is connected to the waste heat utilization unit, and its output pipeline is connected to a second analysis unit. This allows recycled materials to be fed into the absorption unit for absorption and then into the second analysis unit for further analysis. Finally, the analyzed liquid can be fed back into the absorption unit for absorption. This structure allows for full utilization of the reduction tail gas and enables it to be divided into two separate analysis streams, reducing the impact of compositional changes on hydrogen quality. Attached Figure Description

[0029] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 A structural block diagram of the waste heat recovery system for reduction exhaust gas provided in the application embodiment;

[0031] Figure 2 A schematic diagram of the exhaust gas flow direction of the waste heat recovery system provided in the application embodiment. Detailed Implementation

[0032] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme of the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. The components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0033] Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of the present application.

[0034] It should be noted that the reduction furnace generates some different reduction products in different reaction stages, and the main reaction equations are as follows:

[0035] Main reaction:

[0036] SiHCl3(g)+H2(g)=Si(s)+3HCl(g) ———(1353K)

[0037] Part of the side reaction:

[0038] 2SiHCl3(g)=Si(s)+2HCl(g)+SiCl4(g) — (thermal decomposition)

[0039] SiHCl3(g)+H2(g)=SiH2Cl2(g)+HCl(g)

[0040] SiHCl3(g)+2H2(g)=SiH3Cl(g)+2HCl(g)

[0041] SiHCl3(g)=SiCl2(g)+HCl(g)

[0042] 2SiHCl3(g)=SiCl4(g)+SiH2Cl2(g)

[0043] 4SiHCl3(g)=Si(s)+3SiCl4(g)+2H2(g)

[0044] Therefore, the tail gas of the reduction furnace mainly contains silicon tetrachloride, dichlorodihydrogen silicon, trichlorohydrogen silicon, hydrogen chloride and hydrogen, etc., which are high-temperature reduction tail gas generated in the process of producing polycrystalline silicon by improved Siemens method. Embodiment

[0045] Please refer to Figure 1The utility model discloses a reduction tail gas waste heat utilization system, including:

[0046] The utility model provides a reduction tail gas waste heat utilization system, including:

[0047] Waste heat utilization unit, condensing unit, compression unit, chlorosilane buffer tank, first analysis unit, absorption unit and second analysis unit are connected.

[0048] The first input line of waste heat utilization unit is connected with the reduction furnace tail gas output line, and the first output line of waste heat utilization unit is connected with the input line of condensing unit, which is used for sending the reduction tail gas into condensing unit for condensation after waste heat utilization.

[0049] The output line of condensing unit is divided into two ways and is connected with the input line of chlorosilane buffer tank and the input line of compression unit respectively, which is used for sending the liquid phase after condensation into chlorosilane buffer tank and the gas phase after condensation into compression unit.

[0050] The output line of compression unit is connected with the second input line of waste heat utilization unit, which is used for sending the gas phase after compression into waste heat utilization unit for reuse.

[0051] The output line of chlorosilane buffer tank is connected with the input line of first analysis unit, which is used for sending the liquid phase chlorosilane into first analysis unit for analysis.

[0052] The input line of absorption unit is connected with the second output line of waste heat utilization unit, which is used for sending the gas phase after waste heat utilization into absorption unit for absorption, and the output line of absorption unit is connected with the input line of second analysis unit, and the output line of second analysis unit is connected with the input line of absorption unit, which is used for sending the material into second analysis unit for analysis and sending the analysis liquid to absorption unit.

[0053] In the following, one reduction tail gas waste heat utilization system of the example embodiment will be further described.

[0054] In some embodiments of the present application, with reference to Figure 1 The above waste heat utilization unit is a cascade waste heat utilization system, which utilizes the waste heat of reduction tail gas for cascade utilization, fully utilizes the heat of reduction tail gas, achieves maximum utilization, and the entire waste heat utilization unit can select corresponding temperature tail gas or compressed hydrogen according to different temperature cascade to provide energy for devices or equipment with different temperature requirements. The above cascade waste heat utilization system can be one of TCS preheating system, refrigerated water preparation system, heating system or hydrogen preheating system. The first input line of waste heat utilization unit is connected with the reduction furnace tail gas output line, and the first output line of waste heat utilization unit is connected with the input line of condensing unit, which is used for sending the reduction tail gas into condensing unit for condensation after waste heat utilization.

[0055] In some embodiments of the present application, the output pipeline of the condensing unit is divided into two paths and connected to the input pipeline of the chlorosilane buffer tank and the input pipeline of the compression unit respectively, for sending the condensed liquid phase into the chlorosilane buffer tank and sending the condensed gas phase into the compression unit.

[0056] As a preferred embodiment, the condensing unit comprises a first condenser and a second condenser, the input pipeline of the first condenser is connected to the first output pipeline of the waste heat utilization unit, the first condenser is divided into two paths and outputs to the chlorosilane buffer tank and the second condenser; the second condenser is divided into two paths and outputs to the chlorosilane buffer tank and the compression unit. The reduced tail gas after waste heat utilization is sent into the first condenser for condensation, the condensed liquid phase is sent into the chlorosilane buffer tank, and the condensed gas phase is sent into the second condenser for further condensation, the liquid phase is sent to the chlorosilane buffer tank, and the gas phase is sent to the compression unit.

[0057] In some embodiments of the present application, the output pipeline of the compression unit is connected to the second input pipeline of the waste heat utilization unit, for sending the compressed gas phase into the waste heat utilization unit for reuse, which can reuse the compressed gas after temperature rise, and improve the waste heat utilization efficiency.

[0058] As a preferred embodiment, a stripping column reboiler is further included, the compression unit is divided into two paths and outputs to the second input pipeline of the waste heat utilization unit and the input pipeline of the stripping column reboiler; the output pipeline of the stripping column reboiler is merged into the second output pipeline of the waste heat utilization unit and is commonly connected to the input pipeline of the absorption unit. The above structure provides a heat source for the HCL stripping column reboiler, and reuses the waste heat of the compressed gas after temperature rise of the compressor.

[0059] The gas phase after condensation of the condensing unit is compressed by the compression unit, the temperature of the material is raised, and the material is divided into two paths, one path is sent to the stripping column reboiler to provide energy for the stripping column reboiler, and the other path is sent to the waste heat utilization unit for waste heat utilization again. The material after compression of the compression unit is merged with the material after waste heat utilization of the stripping column reboiler, and is sent into the absorption unit.

[0060] In some embodiments of the present application, the output pipeline of the chlorosilane buffer tank is connected to the input pipeline of the first stripping unit, for sending the liquid phase chlorosilane into the first stripping unit for stripping.

[0061] As a preferred embodiment, the first resolving unit comprises a first resolving tower and a first heat exchange unit connected in sequence, the top of the first resolving tower is provided with an HCL output pipeline connected with the HCL pipeline; the bottom of the first resolving tower is a material output pipeline, and the sidewall of the first resolving tower is a material input pipeline. The input pipeline of the first resolving tower is connected with the output pipeline of the chlorosilane buffer tank; the input pipeline of the first heat exchange unit is connected with the hydrogen output pipeline of the absorption unit, and the first heat exchange unit is divided into two output pipelines to the tank area and the hydrogen pipeline, for conveying the resolving liquid of the first resolving tower to the tank area after heat exchange and conveying the hydrogen output by the absorption unit to the hydrogen pipeline after heat exchange.

[0062] Specifically, the liquid phase chlorosilane of the chlorosilane buffer tank is sent to the first resolving tower for resolving, the resolved liquid phase is sent to the tank area after heat exchange through the first heat exchange unit and then combined with part of the resolved liquid phase from the second resolving unit, and the HCL separated from the first resolving tower is discharged from the HCL output pipeline at the top thereof and communicated with the HCL pipeline from the second resolving unit.

[0063] In some embodiments of the present application, the input pipeline of the absorption unit is connected with the second output pipeline of the waste heat utilization unit, for conveying the gas phase after waste heat utilization into the absorption unit for absorption; the output pipeline of the absorption unit is connected with the input pipeline of the second resolving unit, and the output pipeline of the second resolving unit is connected with the input pipeline of the absorption unit, for conveying the material into the second resolving unit for resolving and conveying the resolved liquid to the absorption unit.

[0064] As a preferred embodiment, a third heat exchange unit and a fourth heat exchange unit are further included, the first input pipeline of the third heat exchange unit is connected with the output pipeline of the chlorosilane buffer tank, the first output pipeline of the third heat exchange unit is connected with the input pipeline of the first resolving tower, for conveying the liquid phase chlorosilane output by the chlorosilane buffer tank to the first resolving tower for resolving after heat exchange through the third heat exchange unit;

[0065] The second input pipeline of the third heat exchange unit is connected with the second output pipeline of the waste heat utilization unit; the first input pipeline of the fourth heat exchange unit is connected with the second output pipeline of the third heat exchange unit, and the first output pipeline of the fourth heat exchange unit is output to the absorption unit; for conveying the material after waste heat reutilization to the absorption unit after heat exchange through the third heat exchange unit and the fourth heat exchange unit.

[0066] The second input pipeline of the fourth heat exchange unit is connected with the hydrogen output pipeline of the absorption unit, and the second output pipeline of the fourth heat exchange unit is output to the first heat exchange unit, for conveying the hydrogen discharged from the absorption unit to the hydrogen pipeline after heat exchange.

[0067] The material after heat exchange through the third heat exchange unit and the fourth heat exchange unit, after absorption of chlorosilane in the absorption unit, H2 is discharged from the top of the absorption tower and sent to the fourth heat exchange unit again for heat exchange, and then discharged together with the liquid phase material after resolution from the first resolution tower.

[0068] As a preferred embodiment, the second resolution unit comprises a second resolution tower and a second heat exchange unit, the top of the second resolution tower is provided with an HCL output pipeline connected with an HCL pipeline, and the resolved HCL gas is discharged from the top; the bottom of the second resolution tower is a liquid phase material discharge pipeline, and the side is a material input pipeline.

[0069] The first input pipeline of the second heat exchange unit is connected with the output pipeline of the absorption unit, the first output pipeline of the second heat exchange unit is connected with the input pipeline of the second resolution tower, and the material discharged from the absorption unit is conveyed to the second resolution tower for resolution after heat exchange.

[0070] The second input pipeline of the second heat exchange unit is connected with the material output pipeline of the second resolution tower, and the second output pipeline of the second heat exchange unit is divided into two paths and output to the absorption unit and the tank area, for conveying the material resolved from the second resolution tower to the absorption unit and the tank area after heat exchange. The HCL resolved by the second resolution tower is discharged from the top, and the liquid phase material discharged from the bottom of the resolution tower is preheated by the second heat exchange unit for the required resolution material, and the resolution material after heat exchange is divided into two paths, one path is used as the absorption liquid and is input into the absorption unit, and the other path is combined with the resolution material after heat exchange of the first heat exchange unit and is sent to the tank area.

[0071] As a preferred embodiment, the material output pipeline of the second resolution tower is also divided into two paths and output to the resolution tower reboiler; and the resolution tower reboiler is also output to the third heat exchange unit. The material from the compression unit provides heat for the resolution tower reboiler, the material output from the second resolution tower is input into the third heat exchange unit together with the material from the compression unit after waste heat utilization of the resolution tower reboiler, for further waste heat utilization, and the low-grade heat source is used again for preheating of the first resolution system, thereby improving the waste heat utilization efficiency.

[0072] By the above structural design, the present application divides the reduction tail gas waste heat utilization system into two paths for analysis. One path is for the reduction tail gas condensate to be analyzed separately, i.e. the analysis path is chlorosilane buffer tank-third heat exchange unit-first analysis tower-first heat exchange unit, which is to analyze the HCL in the condensed chlorosilane. The other path is for the circulating material to be directly analyzed, i.e. the analysis path is waste heat utilization unit, analysis tower reboiler-third heat exchange unit-fourth heat exchange unit-absorption unit-second heat exchange unit-second analysis tower-second heat exchange unit-absorption unit, which is to absorb the chlorosilane and HCL in the hydrogen with liquid phase chlorosilane, and then analyze the chlorosilane rich liquid (chlorosilane containing HCL) to separate the HCL. The two paths are not mixed for further analysis. The reduction tail gas condensate is analyzed separately. The circulating material of the original absorption and analysis system is not affected by the change of the reduction tail gas composition, so as to reduce the influence of the system component change on the purity of hydrogen, and also to reduce the steam consumption.

[0073] In a specific embodiment, the high temperature reduction tail gas is sent to the waste heat utilization unit, and after the stepwise waste heat utilization, it is sent to the first condenser for condensation. The liquid phase after condensation is sent to the chlorosilane buffer tank, and the gas phase is sent to the second condenser. After further condensation, the liquid phase is sent to the chlorosilane buffer tank, and the gas phase is sent to the compression unit for temperature rise. The material after temperature rise is divided into two paths and sent to the waste heat utilization unit for waste heat utilization, and to provide energy for the analysis tower reboiler. The material after compression is combined after waste heat utilization and analysis tower reboiler waste heat utilization, sent to the third heat exchange unit for heat exchange, sent to the fourth heat exchange unit for further heat exchange, and sent to the absorption unit after heat exchange with low temperature H2 from the fourth heat exchange unit. The material from the fourth heat exchange unit is sent to the absorption unit after chlorosilane absorption, and H2 is discharged from the top of the absorption tower, sent to the fourth heat exchange unit for heat exchange, and communicated with the liquid phase discharge material from the first analysis tower after first heat exchange. The liquid phase chlorosilane of the chlorosilane buffer tank is sent to the first analysis tower for analysis after heat exchange in the third heat exchange unit. The liquid phase after analysis is sent to the tank area after heat exchange in the first heat exchange unit. HCL from the first analysis tower is discharged from the top and communicated with HCL from the second analysis tower. The material from the absorption unit is introduced into the second analysis tower from the side after preheating in the second heat exchange unit. HCL after analysis in the second analysis tower is discharged from the top, and the liquid phase discharge material from the bottom of the second analysis tower is preheated in the second heat exchange unit for the required analysis material. The analysis material after the second heat exchange unit is divided into two paths, one path is introduced into the absorption unit as absorption liquid, and the other path is combined with the analysis material of the first heat exchange unit and sent to the tank area. The material from the compression unit provides heat for the analysis tower reboiler, heats the material discharged from the second analysis tower in the analysis tower reboiler, and the material from the compression unit is introduced into the third heat exchange unit after waste heat utilization in the analysis tower reboiler for further waste heat utilization.

[0074] The preferred embodiments of the present application have been described above with the preferred embodiments, but are not intended to limit the present application. For those skilled in the art, the present application can have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A reduction tail gas waste heat utilization system, characterized in that, The waste heat utilization unit, the condensing unit, the compression unit, the chlorosilane buffer tank, the first resolving unit, the absorption unit and the second resolving unit are connected by pipelines. The first input pipeline of the waste heat utilization unit is connected with the output pipeline of the reducing furnace tail gas, and the first output pipeline of the waste heat utilization unit is connected with the input pipeline of the condensing unit, so as to send the reducing tail gas after waste heat utilization into the condensing unit for condensation. The output pipeline of the condensing unit is divided into two branches and connected with the input pipeline of the chlorosilane buffer tank and the input pipeline of the compression unit respectively, so as to send the condensed liquid phase into the chlorosilane buffer tank and the condensed gas phase into the compression unit. The output pipeline of the compression unit is connected with the second input pipeline of the waste heat utilization unit, so as to send the compressed gas phase into the waste heat utilization unit for reuse. The output pipeline of the chlorosilane buffer tank is connected with the input pipeline of the first resolving unit, so as to send the liquid phase chlorosilane into the first resolving unit for resolution. The input pipeline of the absorption unit is connected with the second output pipeline of the waste heat utilization unit, so as to send the gas phase after waste heat utilization into the absorption unit for absorption; the output pipeline of the absorption unit is connected with the input pipeline of the second resolving unit, and the output pipeline of the second resolving unit is connected with the input pipeline of the absorption unit, so as to send the material into the second resolving unit for resolution and send the resolved liquid to the absorption unit.

2. The reduced tail gas waste heat utilization system according to claim 1, characterized in that, The condensing unit comprises a first condenser and a second condenser, the input pipeline of the first condenser is connected with the first output pipeline of the waste heat utilization unit, and the first condenser is divided into two branches and output to the chlorosilane buffer tank and the second condenser; the second condenser is divided into two branches and output to the chlorosilane buffer tank and the compression unit.

3. The reduced tail gas waste heat utilization system of claim 1, wherein, A resolving column reboiler is further included, the compression unit is divided into two branches and output to the second input pipeline of the waste heat utilization unit and the input pipeline of the resolving column reboiler; the output pipeline of the resolving column reboiler is incorporated into the second output pipeline of the waste heat utilization unit and connected with the input pipeline of the absorption unit.

4. The reduced tail gas waste heat utilization system of claim 1, wherein, The first resolving unit comprises a first resolving column and a first heat exchange unit connected in sequence, the top of the first resolving column is provided with an HCL output pipeline connected with an HCL pipeline; the input pipeline of the first resolving column is connected with the output pipeline of the chlorosilane buffer tank; the input pipeline of the first heat exchange unit is connected with the hydrogen gas output pipeline of the absorption unit, and the first heat exchange unit is divided into two branches and output to a tank area and a hydrogen gas pipeline, so as to send the resolved liquid of the first resolving column to the tank area after heat exchange and send the hydrogen gas output by the absorption unit to the hydrogen gas pipeline after heat exchange.

5. The reduced tail gas waste heat utilization system according to claim 4, characterized in that, The second resolving unit comprises a second resolving column and a second heat exchange unit, and the top of the second resolving column is provided with an HCL output pipeline connected with the HCL pipeline. The first input pipeline of the second heat exchange unit is connected with the output pipeline of the absorption unit, and the first output pipeline of the second heat exchange unit is connected with the input pipeline of the second stripping column, for conveying the material discharged from the absorption unit to the second stripping column for stripping after heat exchange; The second input pipeline of the second heat exchange unit is connected with the material output pipeline of the second stripping column, and the second output pipeline of the second heat exchange unit is divided into two output pipelines to the absorption unit and the tank area, for conveying the material stripped from the second stripping column to the absorption unit and the tank area after heat exchange.

6. The reduced tail gas waste heat utilization system according to claim 5, wherein, Further comprising a third heat exchange unit and a fourth heat exchange unit, The first input pipeline of the third heat exchange unit is connected with the output pipeline of the chlorosilane buffer tank, and the first output pipeline of the third heat exchange unit is connected with the input pipeline of the first stripping column, for conveying the liquid-phase chlorosilane output from the chlorosilane buffer tank to the first stripping column for stripping after heat exchange; The second input pipeline of the third heat exchange unit is connected with the second output pipeline of the waste heat utilization unit, and the first input pipeline of the fourth heat exchange unit is connected with the second output pipeline of the third heat exchange unit, and the first output pipeline of the second heat exchange unit is output to the absorption unit, for conveying the material after waste heat recycling to the absorption unit after heat exchange.

7. The reduced tail gas waste heat utilization system according to claim 6, wherein, The second input pipeline of the fourth heat exchange unit is connected with the hydrogen output pipeline of the absorption unit, and the second output pipeline of the fourth heat exchange unit is output to the first heat exchange unit, for conveying the hydrogen discharged from the absorption unit to the hydrogen pipeline after heat exchange.

8. The reduced tail gas waste heat utilization system of claim 5, wherein, The material output pipeline of the second stripping column is also divided into two output pipelines to the stripping column reboiler.

9. The reduced tail gas waste heat utilization system of claim 8, wherein, The stripping column reboiler is also output to a heating system.

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