Desorption separation method and system for hydrogen adsorption in polycrystalline silicon tail gas

Abstract

The invention provides a desorption separation method and system for hydrogen adsorption in polycrystalline silicon tail gas. The desorption separation method for hydrogen adsorption in polycrystalline silicon tail gas comprises the following steps: carrying out desorption regeneration treatment on a to-be-regenerated adsorbent by using hot hydrogen to obtain to-be-treated regenerated gas; performing first cooling treatment on the to-be-treated regenerated gas to obtain cooled regenerated gas; carrying out compression treatment on the cooled regenerated gas to obtain compressed regenerated gas; and carrying out condensation-heat exchange treatment on the compressed regenerated gas to obtain regenerated hydrogen and recovered chlorosilane. According to the desorption separation method for adsorbing hydrogen in polycrystalline silicon tail gas, the recycled hydrogen in the adsorption column can be efficiently recycled, and the yield of the recycled hydrogen is improved.

Description

Technical Field

[0001] The invention relates to a method and system for separating hydrogen adsorbed and desorbed from polysilicon tail gas, belonging to the technical field of chemical separation. Background Art

[0002] Currently, the main process for preparing polysilicon in polysilicon production systems is the modified Siemens process, which involves introducing trichlorosilane and hydrogen into a reduction furnace to react and deposit polysilicon on a silicon core at 1100°C. The reduced exhaust gas from the reduction furnace enters the exhaust gas recovery system, which mainly recovers hydrogen, hydrogen chloride, and chlorosilane. The process used is a dry exhaust gas recovery process, specifically, after a four-stage cooling process, the gas phase is separated from the chlorosilane liquid phase. The liquid phase enters a desorption tower to separate the light components to obtain lean liquid chlorosilane, which is then sent to an absorption tower to absorb hydrogen chloride impurities. The gas phase enters the absorption tower, where the lean liquid chlorosilane absorbs hydrogen chloride impurities in the gas phase to produce crude hydrogen. The crude hydrogen then enters an adsorption column to remove impurities and obtain recovered hydrogen. The recovered hydrogen can be returned to the polysilicon reduction process to continue polysilicon production. The hydrogen, hydrogen chloride and chlorosilane separated by the dry tail gas recovery process are sent to the upstream and downstream processes for use respectively, realizing the development of the reduction tail gas production from open to closed circulation.

[0003] However, the adsorption column can not only adsorb impurities in the intermediate hydrogen, but also adsorb part of the hydrogen, which is not conducive to the recovery rate of hydrogen. Summary of the Invention

[0004] The present invention provides a method for separating hydrogen from polysilicon tail gas by adsorption and desorption, which can efficiently recover hydrogen in an adsorption column and improve the yield of recovered hydrogen.

[0005] The present invention provides a system for implementing the above-mentioned desorption separation method, which can efficiently recover the recovered hydrogen in the adsorption column, and the system has a simple structure and is suitable for wide promotion and application.

[0006] The present invention provides a method for separating hydrogen from polysilicon tail gas by adsorption and desorption, which comprises the following steps:

[0007] Using hot hydrogen to desorb and regenerate the adsorbent to be regenerated to obtain regenerated gas to be treated;

[0008] performing a first cooling process on the regeneration gas to be treated to obtain cooled regeneration gas;

[0009] compressing the cooled regenerated gas to obtain compressed regenerated gas;

[0010] The compressed regeneration gas is subjected to condensation-heat exchange treatment to obtain regenerated hydrogen and recover chlorosilane.

[0011] The desorption separation method as described above, wherein, in the desorption regeneration process, the mass ratio of the hot hydrogen to the hydrogen to be treated is 1:(15-30); and / or,

[0012] During the desorption regeneration process, the temperature is 145-180° C. and the pressure is 0.02-0.1 MPaG.

[0013] The desorption separation method as described above, wherein the condensation-heat exchange process comprises:

[0014] performing a second cooling process on the compressed regenerated gas to obtain a first intermediate regenerated hydrogen gas;

[0015] performing a gas-liquid heat exchange process on the first intermediate regenerated hydrogen to obtain a second intermediate regenerated hydrogen and recover chlorosilane;

[0016] performing a gas-to-gas heat exchange treatment on the second intermediate regenerated hydrogen to obtain first low-temperature regenerated hydrogen, recovered hydrogen, and a low-temperature chlorosilane solution;

[0017] condensing the first low-temperature regenerated hydrogen to obtain low-temperature regenerated hydrogen and a low-temperature chlorosilane solution;

[0018] The low-temperature chlorosilane solution participates in the gas-liquid heat exchange treatment, and the low-temperature regenerated hydrogen participates in the gas-gas heat exchange treatment.

[0019] In the desorption separation method as described above, the temperature of the cooled regeneration gas is 40° C., and the pressure of the cooled regeneration gas is 0.02 to 0.05 MPaG.

[0020] In the desorption separation method as described above, the pressure of the compressed regeneration gas is 0.4 to 1.4 MPaG.

[0021] In the desorption separation method as described above, the temperature of the first intermediate regeneration hydrogen is 40° C., and the pressure of the first intermediate regeneration hydrogen is 0.4 to 1.4 MPaG.

[0022] In the desorption separation method as described above, the temperature of the low-temperature regenerated hydrogen is -10 to -60°C, and the pressure of the low-temperature regenerated hydrogen is 0.4 to 1.4 MPaG.

[0023] The present invention provides a system for implementing the above-mentioned desorption separation method, which comprises: an adsorption tower, a first cooler, a regeneration gas compressor, and a condensation-heat exchange unit;

[0024] The adsorption tower has an inlet for hydrogen to be treated, an outlet for recovered hydrogen, an inlet for hot hydrogen and an outlet for regenerated gas to be treated;

[0025] The outlet of the regenerated gas to be treated is connected to the inlet of the first cooler, and the outlet of the first cooler is connected to the inlet of the regenerated gas compressor; the outlet of the regenerated gas compressor is connected to the inlet of the condensing heat exchange unit, and the condensing-heat exchange unit has a regenerated hydrogen outlet and a recovered chlorosilane outlet.

[0026] The system as described above, wherein the condensation-heat exchange unit comprises: a second cooler, a gas-liquid heat exchanger, a gas-gas heat exchanger, and a condenser;

[0027] The outlet of the regeneration gas compressor is communicated with the inlet of the second cooler, the outlet of the second cooler is communicated with the gas phase inlet of the gas-liquid heat exchanger, the gas phase outlet of the gas-liquid heat exchanger is communicated with the heat source inlet of the gas-to-gas heat exchanger, the heat source outlet of the gas-to-gas heat exchanger is communicated with the inlet of the condenser, the gas phase outlet of the condenser is communicated with the cold source inlet of the gas-to-gas heat exchanger, and the cold source outlet of the gas-to-gas heat exchanger is the regenerated hydrogen outlet;

[0028] The liquid phase outlet of the condenser is communicated with the liquid phase inlet of the gas-liquid heat exchanger, the liquid phase outlet of the gas-gas heat exchanger is communicated with the liquid phase inlet of the gas-liquid heat exchanger, and the liquid phase outlet of the gas-liquid heat exchanger is an outlet for recovering chlorosilane.

[0029] The system as described above, wherein further comprising a condensate tank;

[0030] The liquid phase outlet of the gas-to-gas heat exchanger is in communication with the inlet of the condensate tank, and the liquid phase outlet of the condenser is in communication with the inlet of the condensate tank;

[0031] The outlet of the condensate tank is communicated with the liquid phase inlet of the gas-liquid heat exchanger.

[0032] The present invention provides a desorption and separation method for hydrogen adsorbed in polysilicon tail gas, comprising subjecting a regenerated adsorbent to desorption and regeneration to obtain a treated regenerated gas, followed by sequential cooling, compression, and condensation-heat exchange treatments of the treated regenerated gas to obtain regenerated hydrogen and recovery of chlorosilane. The compression treatment followed by the condensation-heat exchange treatment allows for efficient separation of chlorosilane from the treated regenerated gas and various components adsorbed by hydrogen in the polysilicon tail gas, achieving energy savings and cost reductions while efficiently separating the treated regenerated gas.

[0033] The system for implementing the above-mentioned desorption method of the present invention can efficiently recover the recovered hydrogen in the adsorbent to be regenerated, and the system has a simple structure and is suitable for wide promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] To more clearly illustrate the technical solutions in the embodiments of the present invention or related technologies, the following briefly introduces the drawings required for use in the embodiments of the present invention or related technologies. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0035] Figure 1 This is a flow chart of the adsorption and desorption separation of hydrogen in polysilicon tail gas in some embodiments of the present invention;

[0036] Figure 2 This is a flow chart of the desorption separation of hydrogen adsorption in polysilicon tail gas in the comparative example of the present invention.

[0037] Description of reference numerals:

[0038] 1a, 1b: adsorption tower;

[0039] 2: Hydrogen heater;

[0040] 3: Regeneration gas compressor;

[0041] 11: first cooler;

[0042] 21: Second cooler;

[0043] 22: Gas-liquid heat exchanger;

[0044] 23: Gas-to-gas heat exchanger;

[0045] 14: first condenser;

[0046] 15: second condenser;

[0047] 24: condenser;

[0048] 25: condensate tank;

[0049] 26: Pressure pump. DETAILED DESCRIPTION

[0050] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0051] Figure 1 The following is a flow chart of hydrogen adsorption and desorption separation in polysilicon tail gas in some embodiments of the present invention. Figure 1As shown, the first aspect of the present invention provides a method for desorption of hydrogen adsorbed in polysilicon tail gas, comprising the following steps:

[0052] Using hot hydrogen to desorb and regenerate the adsorbent to be regenerated to obtain regenerated gas to be treated;

[0053] Performing a first cooling process on the regenerated gas to be treated to obtain cooled regenerated gas;

[0054] Compressing the cooled regenerated gas to obtain compressed regenerated gas;

[0055] The compressed regenerated gas is subjected to condensation-heat exchange treatment to obtain regenerated hydrogen and recover chlorosilane.

[0056] The polysilicon tail gas of the present invention includes hydrogen, chlorosilanes, and hydrogen chloride. After the polysilicon tail gas undergoes adsorption treatment, the hydrogen chloride and chlorosilanes are adsorbed by an adsorbent, resulting in recovered hydrogen from which the chlorosilanes and hydrogen chloride have been removed, and a regenerated adsorbent adsorbed with the chlorosilanes and hydrogen chloride. In some embodiments, the adsorbent may be activated carbon.

[0057] The present invention does not particularly limit the condensation-heat exchange treatment. The condensation-heat exchange treatment can be: performing condensation treatment and heat exchange treatment in sequence; performing heat exchange treatment and condensation treatment in sequence; performing at least one of heat exchange treatment and condensation treatment alternately.

[0058] The method for desorbing hydrogen from polysilicon tail gas of the present invention specifically comprises: using hot hydrogen to perform desorption and regeneration treatment on an adsorbent to be regenerated, the hot hydrogen will carry away hydrogen chloride and chlorosilane impurities in the adsorbent to be regenerated, thereby obtaining regenerated gas to be treated and a regenerated adsorbent, and the regenerated adsorbent can be used for adsorption treatment again; then performing a first cooling treatment on the regenerated gas to preliminarily cool the regenerated gas to be treated to obtain cooled regenerated gas with a suitable temperature, then compressing the cooled regenerated gas to increase the pressure of the cooled regenerated gas to obtain compressed regenerated gas, then performing a condensation-heat exchange treatment on the compressed regenerated gas to condense and recover the chlorosilane in the compressed regenerated gas, obtaining regenerated hydrogen and recovered chlorosilane, the recovered chlorosilane obtained can be purified in a distillation process and then returned to the system as a recovered raw material, and the obtained regenerated hydrogen can be subjected to a cold hydrogenation process to participate in a cold hydrogenation reaction.

[0059] The desorption separation method of the present invention can efficiently separate various components adsorbed by hydrogen in polysilicon tail gas, achieve efficient regeneration of the adsorbent to be regenerated and efficient separation of the regenerated gas to be treated, and save energy and reduce consumption.

[0060] In some embodiments of the present invention, when the mass ratio of hot hydrogen to hydrogen to be treated is 1:(15-30) during the desorption regeneration process; and / or the temperature is 145-180°C and the pressure is 0.02-0.1 MPaG during the desorption regeneration process, the adsorbent to be regenerated can be more fully desorbed and regenerated while saving energy, thereby obtaining a purer regenerated adsorbent.

[0061] In some embodiments of the present invention, the temperature of the cooled regeneration gas is 40° C., and the pressure of the cooled regeneration gas is 0.02 to 0.05 MPaG; and / or,

[0062] The pressure of the compressed regeneration gas is 0.4~1.4MPaG.

[0063] The present invention can achieve efficient recovery of recovered hydrogen in the adsorbent to be regenerated and improve the yield of recovered hydrogen by regulating the pressure of cooling the regenerated gas before and after compression treatment and compressing the regenerated gas.

[0064] In some embodiments of the present invention, the condensation-heat exchange process includes:

[0065] performing a second cooling process on the compressed regenerated gas to obtain a first intermediate regenerated hydrogen;

[0066] Performing gas-liquid heat exchange treatment on the first intermediate regenerated hydrogen to obtain second intermediate regenerated hydrogen and recovering chlorosilane;

[0067] Performing gas-to-gas heat exchange treatment on the second intermediate regenerated hydrogen to obtain first low-temperature regenerated hydrogen, recovered hydrogen, and low-temperature chlorosilane solution;

[0068] condensing the first low-temperature regenerated hydrogen to obtain low-temperature regenerated hydrogen and a low-temperature chlorosilane solution;

[0069] The low-temperature chlorosilane solution participates in the gas-liquid heat exchange treatment, and the low-temperature regenerated hydrogen participates in the gas-gas heat exchange treatment.

[0070] Specifically, the condensation-heat exchange treatment includes: performing a second cooling treatment on the compressed regeneration gas to initially reduce the temperature of the compressed regeneration gas to obtain a first intermediate regeneration hydrogen; then performing a gas-liquid heat exchange treatment on the first intermediate regeneration hydrogen to further reduce the temperature of the first cold intermediate regeneration hydrogen to obtain a second intermediate regeneration hydrogen; then performing a gas-to-gas heat exchange treatment on the second intermediate regeneration hydrogen to further reduce the temperature of the second intermediate regeneration hydrogen to obtain a first low-temperature regeneration hydrogen and a low-temperature chlorosilane solution; then performing a condensation treatment on the first low-temperature regeneration hydrogen to obtain low-temperature regeneration hydrogen and a low-temperature chlorosilane solution; the low-temperature chlorosilane solution obtained from the gas-to-gas heat exchange treatment and the condensation treatment is used as a heat exchange medium to participate in a gas-liquid heat exchange treatment, and in the gas-liquid heat exchange treatment, the low-temperature chlorosilane solution and the first intermediate regeneration hydrogen are heat exchanged to obtain recovered chlorosilane; the obtained low-temperature regeneration hydrogen is used as a heat exchange medium to participate in a gas-to-gas heat exchange treatment, and in the gas-to-gas heat exchange treatment, the low-temperature regeneration hydrogen and the second intermediate regeneration hydrogen are heat exchanged to obtain recovered hydrogen.

[0071] The present invention can more fully remove impurities from the compressed regeneration gas by sequentially subjecting the compressed regeneration gas to a second cooling process, a gas-liquid heat exchange process, a gas-gas heat exchange process, and a condensation process. Furthermore, the present invention utilizes a low-temperature chlorosilane solution and low-temperature regeneration hydrogen to sequentially cool the first intermediate regeneration hydrogen and the second intermediate regeneration hydrogen, thereby removing chlorosilanes from the first intermediate regeneration hydrogen and the second intermediate regeneration hydrogen. Furthermore, the first intermediate regeneration hydrogen and the second intermediate regeneration hydrogen are utilized to increase the temperatures of the low-temperature chlorosilane solution and the low-temperature regeneration hydrogen, respectively, to obtain recovered chlorosilanes and purified regeneration hydrogen. This fully utilizes the energy in the system and saves energy consumption.

[0072] Furthermore, when the temperature of the low-temperature regenerated hydrogen is -10 to -60°C and the pressure of the low-temperature regenerated hydrogen is 0.4 to 1.4 MPaG, impurities in the first low-temperature regenerated hydrogen can be fully removed to obtain low-temperature regenerated hydrogen with higher purity, and the obtained low-temperature regenerated hydrogen can be returned to participate in the gas-gas heat exchange treatment, and the obtained low-temperature chlorosilane solution can be returned to participate in the gas-liquid heat exchange treatment, thereby fully utilizing the cooling capacity of the low-temperature regenerated hydrogen and the low-temperature chlorosilane solution and saving energy consumption.

[0073] like Figure 1 As shown, the second aspect of the present invention provides a system for implementing the desorption separation method of the first aspect, comprising: an adsorption tower, a first cooler 11, a regeneration gas compressor 3, and a condensation-heat exchange unit;

[0074] The adsorption tower has an inlet for hydrogen to be treated, an outlet for recovered hydrogen, an inlet for hot hydrogen and an outlet for regenerated gas to be treated;

[0075] The outlet of the regenerated gas to be treated is connected to the inlet of the first cooler 11, and the outlet of the first cooler 11 is connected to the inlet of the regenerated gas compressor 3; the outlet of the regenerated gas compressor 3 is connected to the inlet of the condensation-heat exchange unit, and the condensation-heat exchange unit has a regenerated hydrogen outlet and a recovered chlorosilane outlet.

[0076] In the present invention, the adsorption tower can have three ( Figure 1 Two adsorption towers are exemplified in the embodiment, namely, adsorption tower 1a and adsorption tower 1b, wherein one adsorption tower 1a performs adsorption treatment, the other adsorption tower 1b performs desorption treatment, and the third adsorption tower is in standby. In some embodiments, the system further comprises a hydrogen heater 2.

[0077] Specifically, the hydrogen to be treated enters the adsorption tower 1a through the hydrogen to be treated inlet of the adsorption tower 1a. In the adsorption tower 1a, the adsorbent adsorbs components such as hydrogen chloride and chlorosilane in the hydrogen to be treated, thereby purifying the hydrogen and obtaining recovered hydrogen. The recovered hydrogen is heated by the hydrogen heater 2 to obtain hot hydrogen, which enters the adsorption tower 1b through the hot hydrogen inlet of the adsorption tower 1b. In the adsorption tower 1b, the adsorbent to be regenerated that has adsorbed impurities is purged to achieve desorption and regeneration of impurities in the adsorbent to be regenerated, thereby obtaining regenerated gas to be treated containing chlorosilane and hydrogen chloride. The regenerated gas to be treated is output through the regenerated gas to be treated outlet of the adsorption tower 1b, enters the first cooler 11 through the inlet of the first cooler 11, and undergoes a first cooling in the first cooler 11. The cooled regenerated gas is outputted through the outlet of the first cooler 11, enters the regenerated gas compressor 3 through the inlet of the regenerated gas compressor 3, and is compressed in the regenerated gas compressor 3 to obtain compressed regenerated gas; the compressed regenerated gas is then outputted through the outlet of the regenerated gas compressor 3, enters the condensation-heat exchange unit through the inlet of the condensation-heat exchange unit for condensation-heat exchange treatment, in which chlorosilane in the compressed regenerated gas can be removed to obtain regenerated hydrogen and recovered chlorosilane, and the obtained regenerated hydrogen is outputted through the regenerated hydrogen outlet of the condensation-heat exchange unit to go through the cooling hydrogenation process, and the obtained recovered chlorosilane is outputted through the recovered chlorosilane outlet of the condensation-heat exchange unit.

[0078] The system for implementing the above-described desorption and separation method of the present invention not only efficiently regenerates the adsorbent but also efficiently separates the various components adsorbed by hydrogen in polysilicon tail gas, resulting in recovered hydrogen and chlorosilane. Notably, the system of the present invention also reduces energy consumption and has a simple structure, making it suitable for widespread application.

[0079] In some embodiments of the present invention, the condensation-heat exchange unit includes: a second cooler 21, a gas-liquid heat exchanger 22, a gas-gas heat exchanger 23, and a condenser 24;

[0080] The outlet of the regeneration gas compressor 3 is communicated with the inlet of the second cooler 21, the outlet of the second cooler 21 is communicated with the gas phase inlet of the gas-liquid heat exchanger 22, the gas phase outlet of the gas-liquid heat exchanger 22 is communicated with the heat source inlet of the gas-gas heat exchanger 23, the heat source outlet of the gas-gas heat exchanger 23 is communicated with the inlet of the condenser 24, the gas phase outlet of the condenser 24 is communicated with the cold source inlet of the gas-gas heat exchanger 23, and the cold source outlet of the gas-gas heat exchanger 23 is the regenerated hydrogen outlet;

[0081] The liquid phase outlet of the condenser 24 is connected to the liquid phase inlet of the gas-liquid heat exchanger 22, and the liquid phase outlet of the gas-gas heat exchanger 23 is connected to the liquid phase inlet of the gas-liquid heat exchanger 22. The liquid phase outlet of the gas-liquid heat exchanger 22 is an outlet for recovering chlorosilane.

[0082] Specifically, the compressed regenerated gas is output through the outlet of the regenerated gas compressor 3, enters the second cooler 21 through the inlet of the second cooler 21, and undergoes a second cooling treatment in the second cooler 21 to preliminarily reduce the temperature of the compressed regenerated gas to obtain the first intermediate regenerated hydrogen; the first intermediate regenerated hydrogen is output through the outlet of the second cooler 21, enters the gas-liquid heat exchanger 22 through the gas phase inlet of the gas-liquid heat exchanger 22, and undergoes a gas-liquid heat exchange treatment in the gas-liquid heat exchanger 22 to further reduce the temperature of the first intermediate regenerated hydrogen to obtain the second intermediate regenerated hydrogen; then the second intermediate regenerated hydrogen is subjected to the gas-liquid heat exchange The first low-temperature regenerated hydrogen is output from the gas phase outlet of the gas-gas heat exchanger 22, enters the gas-gas heat exchanger 23 through the gas phase inlet of the gas-gas heat exchanger 23, and undergoes gas-gas heat exchange treatment in the gas-gas heat exchanger 23 to remove chlorosilanes in the second intermediate regenerated hydrogen, thereby obtaining a first low-temperature regenerated hydrogen and a low-temperature chlorosilane solution; the first low-temperature regenerated hydrogen is output from the heat source outlet of the gas-gas heat exchanger 23, input through the heat source inlet of the condenser 24, and undergoes condensation treatment in the condenser 24 to reduce the temperature of the first low-temperature regenerated hydrogen and remove chlorosilanes in the first low-temperature regenerated hydrogen, thereby obtaining a low-temperature regenerated hydrogen and a low-temperature chlorosilane solution;

[0083] The low-temperature chlorosilane solution is output through the liquid phase outlet of the gas-to-gas heat exchanger 23, and the low-temperature chlorosilane solution is output through the liquid phase outlet of the condenser 24, and enters the gas-liquid heat exchanger 22 through the liquid phase inlet of the gas-liquid heat exchanger 22. In the gas-liquid heat exchanger 22, the low-temperature chlorosilane solution and the first intermediate regenerated hydrogen undergo gas-liquid heat exchange treatment to obtain heated recovered chlorosilane and cooled second intermediate regenerated hydrogen; the low-temperature regenerated hydrogen is output through the gas phase outlet of the condenser 24, and enters the gas-to-gas heat exchanger 23 through the cold source hot outlet of the gas-to-gas heat exchange treatment. In the gas-to-gas heat exchanger 23, the low-temperature regenerated hydrogen and the second intermediate regenerated hydrogen undergo gas-to-gas heat exchange treatment, the second intermediate regenerated hydrogen is cooled, and the chlorosilane in the second intermediate regenerated hydrogen is separated to obtain the first low-temperature regenerated hydrogen and the low-temperature chlorosilane solution. The low-temperature regenerated hydrogen is heated to obtain regenerated hydrogen, and the obtained regenerated hydrogen is output through the cold source outlet of the gas-to-gas heat exchanger 23.

[0084] When the condensation-heat exchange unit includes the above structure, energy consumption can be further saved, and the various components adsorbed by hydrogen in the polysilicon tail gas can be separated more efficiently.

[0085] In some embodiments of the present invention, a condensate tank 25 is further included;

[0086] The liquid phase outlet of the gas-to-gas heat exchanger 23 is connected to the inlet of the condensate tank 25, and the liquid phase outlet of the condenser 24 is connected to the inlet of the condensate tank;

[0087] The outlet of the condensate tank 25 is communicated with the liquid phase inlet of the gas-liquid heat exchanger 22 .

[0088] Specifically, the low-temperature chlorosilane solution is output through the liquid phase outlet of the gas-to-gas heat exchanger 23 and enters the condensate tank 25 through the inlet of the condensate tank 25. The low-temperature chlorosilane solution is output through the liquid phase outlet of the condenser 24 and enters the condensate tank 25 through the inlet of the condensate tank 25. The low-temperature chlorosilane solution is output through the outlet of the condensate tank 25 and enters the gas-liquid heat exchanger 22 through the liquid phase inlet of the gas-liquid heat exchanger 22.

[0089] In some embodiments, a pressure pump 26 may be used to pressurize the low-temperature chlorosilane solution in the condensate tank 25 and send it out, and then enter the gas-liquid heat exchanger 22 through the liquid phase inlet of the gas-liquid heat exchanger 22 as a heat exchange medium.

[0090] Example 1

[0091] The desorption separation system for hydrogen adsorption in polysilicon tail gas of this embodiment is as follows Figure 1 Shown, including:

[0092] Adsorption tower 1a, adsorption tower 1b, hydrogen heater 2, regeneration gas compressor 3, first cooler 11, second cooler 21, gas-liquid heat exchanger 22, gas-gas heat exchanger 23, condenser 24, condensate tank 25, pressure pump 26;

[0093] The adsorption tower has an inlet for hydrogen to be treated, an outlet for recovered hydrogen, an inlet for hot hydrogen and an outlet for regenerated gas to be treated;

[0094] The outlet of the regenerated gas to be treated is communicated with the inlet of the first cooler 11, and the outlet of the first cooler 11 is communicated with the inlet of the regenerated gas compressor 3; the outlet of the regenerated gas compressor 3 is communicated with the inlet of the second cooler 21, and the outlet of the second cooler 21 is communicated with the gas phase inlet of the gas-liquid heat exchanger 22, and the gas phase outlet of the gas-liquid heat exchanger 22 is communicated with the heat source inlet of the gas-gas heat exchanger 23, and the heat source outlet of the gas-gas heat exchanger 23 is communicated with the inlet of the condenser 24, and the gas phase outlet of the condenser 24 is communicated with the cold source inlet of the gas-gas heat exchanger 23, and the cold source outlet of the gas-gas heat exchanger 23 is the regenerated hydrogen outlet;

[0095] The liquid phase outlet of the condenser 24 is connected to the inlet of the condensate tank 25, the liquid phase outlet of the gas-to-gas heat exchanger 23 is connected to the inlet of the condensate tank 25, the outlet of the condensate tank 25 is connected to the inlet of the pressure pump 26, the outlet of the pressure pump 26 is connected to the liquid phase inlet of the gas-liquid heat exchanger 22, and the liquid phase outlet of the gas-liquid heat exchanger 22 is the outlet for recovering chlorosilane.

[0096] The method for separating hydrogen adsorbed and desorbed from polysilicon tail gas in this embodiment is performed using the above-mentioned system, including:

[0097] The hydrogen to be treated enters the adsorption tower 1a through the hydrogen to be treated inlet of the adsorption tower 1a. In the adsorption tower 1a, the adsorbent adsorbs components such as hydrogen chloride and chlorosilane in the hydrogen to be treated, thereby purifying the hydrogen and obtaining recovered hydrogen. The recovered hydrogen is heated by the hydrogen heater 2 to obtain hot hydrogen, which enters the adsorption tower 1b through the hot hydrogen inlet of the adsorption tower 1b. In the adsorption tower 1b, the adsorbent to be regenerated that adsorbs impurities is purged to achieve desorption and regeneration of impurities in the adsorbent to be regenerated, thereby obtaining regenerated gas to be treated containing chlorosilane and hydrogen chloride. The regenerated gas to be treated is output through the regenerated gas outlet to be treated of the adsorption tower 1b, enters the first cooler 11 through the inlet of the first cooler 11, and performs a first cooling treatment in the first cooler 11 to reduce the temperature of the regenerated gas to be treated, thereby obtaining cooled regenerated gas. The cooled regenerated gas is output through the outlet of the first cooler 11, enters the regenerated gas compressor 3 through the inlet of the regenerated gas compressor 3, and is compressed in the regenerated gas compressor 3 to obtain compressed regenerated gas.

[0098] Then the compressed regenerated gas is outputted through the outlet of the regenerated gas compressor 3, enters the second cooler 21 through the inlet of the second cooler 21, undergoes a second cooling treatment in the second cooler 21, preliminarily reduces the temperature of the compressed regenerated gas, and obtains the first intermediate regenerated hydrogen; the first intermediate regenerated hydrogen is outputted through the outlet of the second cooler 21, enters the gas-liquid heat exchanger 22 through the gas phase inlet of the gas-liquid heat exchanger 22, undergoes a gas-liquid heat exchange treatment in the gas-liquid heat exchanger 22, further reduces the temperature of the first intermediate regenerated hydrogen, and obtains the second intermediate regenerated hydrogen; then the second intermediate regenerated hydrogen is outputted through the gas-liquid heat exchanger The first low-temperature regenerated hydrogen is output from the gas phase outlet of the gas-gas heat exchanger 22, enters the gas-gas heat exchanger 23 through the gas phase inlet of the gas-gas heat exchanger 23, and undergoes gas-gas heat exchange treatment in the gas-gas heat exchanger 23 to remove the chlorosilane in the second intermediate regenerated hydrogen, thereby obtaining a first low-temperature regenerated hydrogen and a low-temperature chlorosilane solution; the first low-temperature regenerated hydrogen is output from the heat source outlet of the gas-gas heat exchanger 23, input through the heat source inlet of the condenser 24, and undergoes condensation treatment in the condenser 24 to reduce the temperature of the first low-temperature regenerated hydrogen and remove the chlorosilane in the first low-temperature regenerated hydrogen, thereby obtaining a low-temperature regenerated hydrogen and a low-temperature chlorosilane solution;

[0099] The low-temperature chlorosilane solution is output through the liquid phase outlet of the gas-gas heat exchanger 23, and the low-temperature chlorosilane solution is output through the liquid phase outlet of the condenser 24, and enters the condensate tank 25 through the inlet of the condensate tank 25. The low-temperature chlorosilane solution is output through the outlet of the condensate tank 25, and after being pressurized by the pressure pump 26, it enters the gas-liquid heat exchanger 22 through the liquid phase inlet of the gas-liquid heat exchanger 22. In the gas-liquid heat exchanger 22, the low-temperature chlorosilane solution and the first intermediate regenerated hydrogen are subjected to gas-liquid heat exchange treatment to obtain the recovered chlorosilane after heating and the second cooled chlorosilane. Intermediate regenerated hydrogen; the low-temperature regenerated hydrogen is output through the gas phase outlet of the condenser 24, and enters the gas-to-gas heat exchanger 23 through the cold source hot port of the gas-to-gas heat exchange treatment. In the gas-to-gas heat exchanger 23, the low-temperature regenerated hydrogen and the second intermediate regenerated hydrogen are subjected to gas-to-gas heat exchange treatment, the second intermediate regenerated hydrogen is cooled, and the chlorosilane in the second intermediate regenerated hydrogen is separated to obtain the first low-temperature regenerated hydrogen and the low-temperature chlorosilane solution. The low-temperature regenerated hydrogen is heated to obtain regenerated hydrogen, and the obtained regenerated hydrogen is output through the cold source outlet of the gas-to-gas heat exchanger 23;

[0100] Among them, in the desorption regeneration treatment, the mass ratio of hot hydrogen to hydrogen to be treated is 1:23.7, the temperature is 160℃, and the pressure is 0.06MPaG;

[0101] The regeneration gas to be treated includes, by mass percentage, 22.75% hydrogen, 10.5 PPB hydrogen chloride, 19.91% dichlorosilane, 48.17% trichlorosilane, and 9.17% silicon tetrachloride;

[0102] The temperature of the cooled regenerated gas is 40°C, the pressure before the regenerated gas compressor 3 (cooled regenerated gas) is 0.04 MPaG, the pressure after the regenerated gas compressor 3 (compressed regenerated gas) is 0.65 MPaG, and the temperature of the first intermediate regenerated hydrogen is 40°C;

[0103] The temperature of low-temperature regenerated hydrogen is -35°C, the pressure of low-temperature regenerated hydrogen is 0.65MPaG; the temperature of regenerated hydrogen is 30°C, and the temperature of recovered chlorosilane is 25°C;

[0104] The regenerated hydrogen includes, by mass percentage, 63.48% hydrogen, 28.5 PPB hydrogen chloride, 19.51% dichlorosilane, 16.45% trichlorosilane, and 0.56% silicon tetrachloride;

[0105] In this embodiment, the total circulating water consumption of the first cooler 11, the second cooler 21 and the regeneration gas compressor 3 is 0.354 kW·h / kg of regeneration gas to be treated, the condenser 24 uses a -40°C refrigerant, and the cooling capacity consumption is 0.047 kW·h / kg of regeneration gas to be treated; the compression load of the regeneration gas compressor 3 is 0.229 kW·h / kg of regeneration gas to be treated.

[0106] Example 2

[0107] The method for separating hydrogen adsorbed and desorbed from polysilicon tail gas in this embodiment is carried out using the system of Example 1. The difference from Example 1 is as follows:

[0108] The pressure after the regeneration gas compressor 3 (compressed regeneration gas) is 1.4 MPaG;

[0109] The temperature of low-temperature regenerated hydrogen is -22°C, the pressure of low-temperature regenerated hydrogen is 1.4MPaG; the temperature of regenerated hydrogen is 30°C, and the temperature of recovered chlorosilane is 30°C;

[0110] The regenerated hydrogen includes, by mass percentage, 63.08% hydrogen, 28.1 PPB hydrogen chloride, 19.19% dichlorosilane, 17.06% trichlorosilane, and 0.66% silicon tetrachloride;

[0111] In this embodiment, the total circulating water consumption of the first cooler 11, the second cooler 21 and the regeneration gas compressor 3 is 0.463 kW·h / kg of regeneration gas to be treated, the condenser 24 uses a -25°C refrigerant, and the cooling capacity consumption is 0.046 kW·h / kg of regeneration gas to be treated; the compression load of the regeneration gas compressor 3 is 0.337 kW·h / kg of regeneration gas to be treated.

[0112] Comparative Example

[0113] The desorption separation system for hydrogen adsorption in the polysilicon tail gas of this comparative example is as follows Figure 2 Shown, including:

[0114] Adsorption tower 1a, adsorption tower 1b, hydrogen heater 2, regeneration gas compressor 3, first cooler 11, second cooler 21, gas-liquid heat exchanger 22, gas-gas heat exchanger 23, first condenser 14, second condenser 15, condensate tank 25, pressure pump 26;

[0115] The adsorption tower has an inlet for hydrogen to be treated, an outlet for recovered hydrogen, an inlet for hot hydrogen and an outlet for regenerated gas to be treated;

[0116] The outlet of the regenerated gas to be treated is communicated with the inlet of the first cooler 11, the outlet of the first cooler 11 is communicated with the gas phase inlet of the gas-liquid heat exchanger 22, the liquid phase outlet of the gas-liquid heat exchanger 22 is the outlet for recovering chlorosilane, the gas phase outlet of the gas-liquid heat exchanger 22 is communicated with the heat source inlet of the gas-gas heat exchanger 23, the heat source outlet of the gas-gas heat exchanger 23 is communicated with the heat source inlet of the first condenser 14, the heat source outlet of the first condenser 14 is communicated with the heat source inlet of the second condenser 15, the heat source outlet of the second condenser 15 is communicated with the cold source inlet of the gas-gas heat exchanger 23, the cold source outlet of the gas-gas heat exchanger 23 is communicated with the inlet of the regenerated gas compressor 3, the outlet of the regenerated gas compressor 3 is communicated with the inlet of the second cooler 21, and the outlet of the second cooler 21 is the rehydrogen outlet;

[0117] The liquid phase outlet of the gas-to-gas heat exchanger 23 is connected to the inlet of the condensate tank 25, the liquid phase outlet of the first condenser 14 is connected to the inlet of the condensate tank 25, the liquid phase outlet of the second condenser 15 is connected to the inlet of the condensate tank 25, the outlet of the condensate tank 25 is connected to the inlet of the pressure pump 26, the outlet of the pressure pump 26 is connected to the liquid phase inlet of the gas-liquid heat exchanger 22, and the liquid phase outlet of the gas-liquid heat exchanger 22 is the outlet for recovering chlorosilane.

[0118] The method for separating hydrogen adsorbed from polysilicon tail gas in this comparative example by desorption is carried out using the above-mentioned system, including:

[0119] The hydrogen to be treated enters the adsorption tower 1a through the hydrogen to be treated inlet of the adsorption tower 1a. In the adsorption tower 1a, the adsorbent adsorbs components such as hydrogen chloride and chlorosilane in the hydrogen to be treated, thereby purifying the hydrogen and obtaining recovered hydrogen. The recovered hydrogen is heated by the hydrogen heater 2 to obtain hot hydrogen, which enters the adsorption tower 1b through the hot hydrogen inlet of the adsorption tower 1b. In the adsorption tower 1b, the adsorbent to be regenerated that has adsorbed impurities is purged to achieve desorption and regeneration of impurities in the adsorbent to be regenerated, thereby obtaining regenerated gas to be treated containing chlorosilane and hydrogen chloride. The regenerated gas to be treated is output through the regenerated gas to be treated outlet of the adsorption tower 1b, enters the first cooler 11 through the inlet of the first cooler 11, and undergoes a first cooling treatment in the first cooler 11 to reduce the temperature of the regenerated gas to be treated, thereby obtaining cooled regenerated gas.

[0120] The cooled regenerated gas is output through the outlet of the first cooler 11, enters the gas-liquid heat exchanger 22 through the gas phase inlet of the gas-liquid heat exchanger 22, undergoes gas-liquid heat exchange treatment in the gas-liquid heat exchanger 22, and obtains a first intermediate regenerated hydrogen. The first intermediate regenerated hydrogen is output through the gas phase outlet of the gas-liquid heat exchanger 22, enters the gas-gas heat exchanger 23 through the heat source inlet of the gas-gas heat exchanger 23, and undergoes gas-gas heat exchange treatment to obtain a second intermediate regenerated hydrogen and a low-temperature chlorosilane solution; the second intermediate regenerated hydrogen is output through the heat source outlet of the gas-gas heat exchanger 23, enters the first condenser 14 through the heat source inlet of the first condenser 14, and undergoes a first condensation treatment in the first condenser 14 to obtain a low-temperature chlorosilane solution and the first low-temperature regenerated hydrogen; the first low-temperature regenerated hydrogen is output through the heat source outlet of the first condenser 14, enters the second condenser 15 through the heat source inlet of the second condenser 15, and undergoes a second condensation treatment in the second condenser 15 to obtain a low-temperature chlorosilane solution and low-temperature regenerated hydrogen;

[0121] The low-temperature regenerated hydrogen is output through the heat source outlet of the second condenser 15, enters the gas-to-gas heat exchanger 23 through the cold source inlet of the gas-to-gas heat exchanger 23, and undergoes heat exchange with the first intermediate regenerated hydrogen in the gas-to-gas heat exchanger 23. The low-temperature regenerated hydrogen is heated to obtain the regenerated hydrogen to be compressed, and the first intermediate regenerated hydrogen is cooled to obtain the second intermediate regenerated hydrogen and the low-temperature chlorosilane solution. The regenerated hydrogen to be compressed is output through the cold source outlet of the gas-to-gas heat exchanger 23, enters the regenerated gas compressor 3 through the inlet of the regenerated gas compressor 3, and is compressed to obtain compressed regenerated hydrogen. The compressed regenerated hydrogen is output through the outlet of the regenerated gas compressor 3, enters the second cooler 21 through the inlet of the second cooler 21, and undergoes a second cooling treatment in the second cooler 21 to obtain regenerated hydrogen.

[0122] The low-temperature chlorosilane solution is output through the liquid phase outlet of the gas-to-gas heat exchanger 23, the low-temperature chlorosilane solution is output through the liquid phase outlet of the first condenser 14, the low-temperature chlorosilane solution is output through the liquid phase outlet of the second condenser 15, and enters the condensate tank 25 through the inlet of the condensate tank 25. Then, after the low-temperature chlorosilane solution is pumped out by the pressure pump 26, it enters the gas-liquid heat exchanger 22 through the liquid phase inlet. Heat exchange is performed in the gas-liquid heat exchanger 22. After the low-temperature chlorosilane solution is heated, the recovered chlorosilane is output through the liquid phase outlet of the gas-liquid heat exchanger 22.

[0123] In the desorption regeneration process, the mass ratio of hot hydrogen to hydrogen to be treated is 1:23.7, the desorption regeneration temperature is 160°C, and the pressure is 0.06MPaG;

[0124] The regeneration gas to be treated includes, by mass percentage, 22.75% hydrogen, 10.5 PPB hydrogen chloride, 19.91% dichlorosilane, 48.17% trichlorosilane, and 9.17% silicon tetrachloride;

[0125] The temperature of the cooled regenerated gas is 40°C, the temperature of the first low-temperature regenerated hydrogen is -35°C, and the temperature of the low-temperature regenerated hydrogen is -60°C;

[0126] The pressure before the regeneration gas compressor 3 (regeneration hydrogen to be compressed) is 0.04 MPaG, the pressure after the regeneration gas compressor 3 (compressed regeneration hydrogen) is 0.65 MPaG, the temperature of the regeneration hydrogen is 40°C, and the temperature of the recovered chlorosilane is 25°C;

[0127] The regenerated hydrogen includes, by mass percentage, 63.06% hydrogen, 28.6 PPB hydrogen chloride, 20.29% dichlorosilane, 16.24% trichlorosilane, and 0.41% silicon tetrachloride;

[0128] In the comparative example, the total circulating water consumption of the first cooler 11, the second cooler 21 and the regeneration gas compressor 3 is 0.316 kW·h / kg of regeneration gas to be treated, the first condenser 14 uses -40°C refrigerant, and the cooling capacity consumption is 0.0031 kW·h / kg of regeneration gas to be treated, and the second condenser 15 uses -65°C refrigerant, and the cooling capacity consumption is 0.0523 kW·h / kg of regeneration gas to be treated; the compression load of the regeneration gas compressor 3 is 0.209 kW·h / kg of regeneration gas to be treated. If the outlet pressure of the regeneration gas compressor 3 is increased to 1.4 MPaG, the compression load of the regeneration gas compressor 3 is 0.311 kW·h / kg of regeneration gas to be treated.

[0129] It can be seen from Examples 1, 2 and the comparative example that: the purity of hydrogen in the regenerated hydrogen is better in Examples 1 and 2 than in the comparative example; Examples 1 and 2 adopt pressurized condensation, which is conducive to the replacement of high-grade refrigerant with low-grade refrigerant. Specifically, the circulating water consumption in Examples 1 and 2 is higher than that in the comparative example, and the cooling capacity of the low-temperature refrigerant is lower than that in the comparative example. In addition to consuming electricity, the low-temperature refrigerant production process also consumes corresponding circulating water. Considering the circulating water consumption of the low-temperature refrigerant, the circulating water consumption in Examples 1 and 2 is not higher than that in the comparative example.

[0130] The cooling capacity consumption and the compressor load are converted into power consumption. The refrigerant power consumption empirical conversion coefficient is: -25℃ refrigerant: 0.31, -40℃ refrigerant: 0.67, -65℃ refrigerant: 1.34; the compressor efficiency is 0.8; in Example 1, the refrigerant power consumption is 0.032kW·h / kg of regenerated gas to be treated, the power consumption of regenerated gas compressor 3 is 0.285kW·h / kg of regenerated gas to be treated, and the total power consumption is 0.317kW·h / kg of regenerated gas to be treated; in Example 2, the refrigerant power consumption is 0.014kW·h / kg of regenerated gas to be treated, and the power consumption of regenerated gas compressor 3 is 0 .421kW·h / kg of regeneration gas to be treated, and the total power consumption is 0.435kW·h / kg of regeneration gas to be treated; in the comparative example, the refrigerant power consumption is 0.070kW·h / kg of regeneration gas to be treated, and when the outlet pressure of the regeneration gas compressor 3 is 0.65MPaG, the power consumption is 0.261kW·h / kg of regeneration gas to be treated, and the total power consumption is 0.331kW·h / kg of regeneration gas to be treated, and when the outlet pressure of the regeneration gas compressor 3 is 1.4MPaG, the power consumption is 0.389kW·h / kg of regeneration gas to be treated, and the total power consumption is 0.459kW·h / kg of regeneration gas to be treated;

[0131] After being fed to the cold hydrogenation process, the regenerated hydrogen needs to be pressurized before use. Therefore, the comparison was conducted at the same pressure. Compared with the comparative example with a regenerated hydrogen pressure of 0.65 MPaG, the power consumption in Example 1 was reduced by 4.23%. Compared with the comparative example with a regenerated hydrogen pressure of 1.4 MPaG, the power consumption in Example 2 was reduced by 5.23%.

[0132] At the same time, since each embodiment of the present invention only uses one-stage low-temperature refrigerant condensation, the corresponding heat exchange equipment, refrigeration units and pipelines will be reduced accordingly, saving corresponding investment, maintenance and operating costs; in addition, according to the downstream receiving pressure, the pressure pump 26 in Examples 1 and 2 can be cancelled as appropriate, saving corresponding investment, maintenance and operating costs of the pump.

[0133] Each embodiment in this specification is described in a related manner. Similar parts between the embodiments can be referred to in conjunction with each other. Each embodiment focuses on the differences from other embodiments. The above are only preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are included in the scope of protection of the present invention.

Claims

1. A method for separating hydrogen from polysilicon tail gas by adsorption and desorption, characterized in that: The following steps are involved: Using hot hydrogen to desorb and regenerate the adsorbent to be regenerated to obtain regenerated gas to be treated; performing a first cooling process on the regeneration gas to be treated to obtain cooled regeneration gas; compressing the cooled regenerated gas to obtain compressed regenerated gas; The compressed regeneration gas is subjected to condensation-heat exchange treatment to obtain regenerated hydrogen and recover chlorosilane.

2. The desorption separation method according to claim 1, characterized in that In the desorption regeneration process, the mass ratio of hot hydrogen to hydrogen to be treated is 1:(15-30); and / or, During the desorption regeneration process, the temperature is 145-180° C. and the pressure is 0.02-0.1 MPaG.

3. The desorption separation method according to claim 1 or 2, characterized in that: The condensation-heat exchange process includes: performing a second cooling process on the compressed regenerated gas to obtain a first intermediate regenerated hydrogen gas; performing a gas-liquid heat exchange process on the first intermediate regenerated hydrogen to obtain a second intermediate regenerated hydrogen and recover chlorosilane; performing a gas-to-gas heat exchange treatment on the second intermediate regenerated hydrogen to obtain first low-temperature regenerated hydrogen, recovered hydrogen, and a low-temperature chlorosilane solution; condensing the first low-temperature regenerated hydrogen to obtain low-temperature regenerated hydrogen and a low-temperature chlorosilane solution; The low-temperature chlorosilane solution participates in the gas-liquid heat exchange treatment, and the low-temperature regenerated hydrogen participates in the gas-gas heat exchange treatment.

4. The desorption separation method according to any one of claims 1 to 3, characterized in that: The temperature of the cooling regeneration gas is 40° C., and the pressure of the cooling regeneration gas is 0.02-0.05 MPaG.

5. The desorption separation method according to any one of claims 1 to 4, characterized in that: The pressure of the compressed regeneration gas is 0.4-1.4 MPaG.

6. The desorption separation method according to claim 3, characterized in that: The temperature of the first intermediate regeneration hydrogen is 40° C., and the pressure of the first intermediate regeneration hydrogen is 0.4-1.4 MPaG.

7. The desorption separation method according to claim 3 or 6, characterized in that: The temperature of the low-temperature regeneration hydrogen is -10 to -60°C, and the pressure of the low-temperature regeneration hydrogen is 0.4 to 1.4 MPaG.

8. A system for implementing the desorption separation method according to any one of claims 1 to 7, characterized in that: include: Adsorption tower, first cooler, regeneration gas compressor and condensation-heat exchange unit; The adsorption tower has an inlet for hydrogen to be treated, an outlet for recovered hydrogen, an inlet for hot hydrogen and an outlet for regenerated gas to be treated; The outlet of the regenerated gas to be treated is connected to the inlet of the first cooler, and the outlet of the first cooler is connected to the inlet of the regenerated gas compressor; the outlet of the regenerated gas compressor is connected to the inlet of the condensation-heat exchange unit, and the condensation-heat exchange unit has a regenerated hydrogen outlet and a recovered chlorosilane outlet.

9. The system according to claim 8, characterized in that The condensation-heat exchange unit includes: a second cooler, a gas-liquid heat exchanger, a gas-gas heat exchanger, and a condenser; The outlet of the regeneration gas compressor is communicated with the inlet of the second cooler, the outlet of the second cooler is communicated with the gas phase inlet of the gas-liquid heat exchanger, the gas phase outlet of the gas-liquid heat exchanger is communicated with the heat source inlet of the gas-to-gas heat exchanger, the heat source outlet of the gas-to-gas heat exchanger is communicated with the inlet of the condenser, the gas phase outlet of the condenser is communicated with the cold source inlet of the gas-to-gas heat exchanger, and the cold source outlet of the gas-to-gas heat exchanger is the regenerated hydrogen outlet; The liquid phase outlet of the condenser is communicated with the liquid phase inlet of the gas-liquid heat exchanger, the liquid phase outlet of the gas-gas heat exchanger is communicated with the liquid phase inlet of the gas-liquid heat exchanger, and the liquid phase outlet of the gas-liquid heat exchanger is an outlet for recovering chlorosilane.

10. The system according to claim 9, characterized in that Also included is a condensate tank; The liquid phase outlet of the gas-to-gas heat exchanger is in communication with the inlet of the condensate tank, and the liquid phase outlet of the condenser is in communication with the inlet of the condensate tank; The outlet of the condensate tank is communicated with the liquid phase inlet of the gas-liquid heat exchanger.

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