Cold hydrogenation production system and production process

Abstract

A cold hydrogenation production system and production process. The cold hydrogenation production system comprises a cold hydrogenation reaction device, a first heat-exchange device, a gas-solid separation device, a second heat-exchange device and a third heat-exchange device, which are sequentially connected. The production system and the production process can increase the utilization rate of reactants and promote a reaction to proceed towards the generation of trichlorosilane, such that the single-pass conversion rate from silicon tetrachloride to trichlorosilane can be increased; in addition, reaction heat generated during a cold hydrogenation reaction process is used as a heat source, and reaction waste heat is recovered by means of multi-stage heat extraction, such that the reaction waste heat is utilized in a scientific, rational and cascaded manner. The production system and the production process have characteristics such as a good energy integration effect, significant energy conservation and consumption reduction, and high waste-heat utilization efficiency.

Description

Cold hydrogenation production system and production process

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on January 3, 2024, with application number 202410004084.X, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application belongs to the technical field of polysilicon production, and for example relates to a cold hydrogenation production system and production process. Background Art

[0003] Polysilicon is the primary raw material for semiconductors and solar photovoltaic cells, typically produced using the silane process or a modified Siemens process. During the polysilicon production process, approximately 25% of trichlorosilane is converted into polysilicon, forming silicon tetrachloride as a byproduct. Silicon tetrachloride decomposes into silicic acid and the highly toxic gas hydrogen chloride when exposed to moist air. This decomposes into silicic acid and hydrogen chloride, which are extremely harmful to humans and can cause widespread crop yield reductions or even complete failures. Even using cutting-edge technology, nearly four tons of silicon tetrachloride are generated for every ton of polysilicon produced. With the rapid expansion of polysilicon production in recent years, significant quantities of silicon tetrachloride have been generated. To prevent environmental pollution, silicon tetrachloride must be recovered and reused.

[0004] The cold hydrogenation method is the main method in the industry to recycle and utilize the reduction by-product silicon tetrachloride and provide trichlorosilane, a raw material for polysilicon production. However, this method still has problems such as low reaction conversion rate and insufficient thermal energy utilization. Summary of the Invention

[0005] The present application provides a cold hydrogenation production system and production process, which can improve the conversion rate of silicon tetrachloride, reduce the heat supplement of the reaction system, and reduce energy consumption.

[0006] The present application provides a cold hydrogenation production system, which includes a cold hydrogenation reaction unit, a first heat exchange unit, a gas-solid separation unit, a second heat exchange unit, and a third heat exchange unit connected in sequence; the material outlet of the cold hydrogenation reaction unit is connected to the heat medium inlet of the first heat exchange unit, the heat medium outlet of the first heat exchange unit is connected to the material inlet of the gas-solid separation unit, and the cold medium outlet of the first heat exchange unit is connected to the cold hydrogenation reaction unit; the gas outlet of the gas-solid separation unit is connected to the heat medium inlet of the second heat exchange unit, and the solid outlet of the gas-solid separation unit is connected to the cold hydrogenation reaction unit; the cold medium inlet of the second heat exchange unit is connected to the material outlet of the first mixing unit, the cold medium outlet of the second heat exchange unit is connected to the second mixing unit, and the material outlet of the second mixing unit is connected to the cold medium inlet of the first heat exchange unit; the hot medium outlet of the second heat exchange unit is connected to the heat medium inlet of the third heat exchange unit, the cold medium inlet of the third heat exchange unit is connected to the material outlet of a silicon tetrachloride storage unit, the cold medium outlet of the third heat exchange unit is connected to the material inlet of a heating unit, and the material outlet of the heating unit is connected to the inlet of the second mixing unit.

[0007] In one or more embodiments, the cold hydrogenation production system further includes at least one heat extraction device, which includes at least one of an absorption refrigeration device, an organic Rankine cycle device, and a heating device; wherein the heat extraction device is connected to the heat medium outlet of the third heat exchange device.

[0008] In one or more embodiments, a washing device is provided between the heat extraction device and the third heat exchange device.

[0009] In one or more embodiments, the material outlet of the last-stage heat extraction device is connected to the material inlet of the gas-liquid separation device, the gas outlet of the gas-liquid separation device is connected to the first mixing device through the first gas recovery pipeline, and the liquid outlet of the gas-liquid separation device is connected to the washing liquid inlet of the washing device.

[0010] In one or more embodiments, the material inlet of the cold hydrogenation reaction device is connected to a silicon powder feed pipeline and a catalyst feed pipeline; the material inlet of the first mixing device is connected to a hydrogen chloride storage device and a hydrogen storage device.

[0011] In one or more embodiments, a chlorosilane liquid discharge pipeline is drawn from the outlet of the gas-liquid separation device. This chlorosilane liquid discharge pipeline and the chlorosilane washing liquid pipeline at the outlet of the washing device are connected to the heat medium inlet of the fourth heat exchange device. The heat medium outlet of the fourth heat exchange device is connected to the inlet of the first condenser. Chilled water circulates between the absorption refrigeration device and the fourth heat exchange device via a chilled circulating water pipeline. Furthermore, the gas outlet of the first condenser is connected to the first mixing device via a second gas recovery pipeline, and the liquid outlet of the first condenser is connected to the distillation unit pipeline.

[0012] The present application also provides a cold hydrogenation production process, which includes:

[0013] After mixing hydrogen chloride, hydrogen and chlorosilane, a first preheating is performed;

[0014] performing a second preheating on silicon tetrachloride, and gasifying the second preheated silicon tetrachloride;

[0015] The vaporized silicon tetrachloride is mixed with the hydrogen chloride, hydrogen and chlorosilane after the first preheating, and then subjected to a third preheating and a cold hydrogenation reaction to obtain a gas-solid mixture;

[0016] The gas-solid mixture is used as a heat source for the third preheating and then subjected to gas-solid separation. The obtained solid is returned for cold hydrogenation reaction, and the obtained gas is used as a heat source for the first preheating and the second preheating in sequence.

[0017] In one or more embodiments, the gas after the second preheating is washed and used for heat extraction, wherein the heat extraction includes at least one of absorption refrigeration, organic Rankine cycle, or heating.

[0018] In one or more embodiments, the gas-liquid mixture after heat removal is subjected to gas-liquid separation, the obtained gas is mixed with hydrogen chloride, hydrogen and chlorosilane, and then subjected to a first preheating, and the obtained liquid is reused for washing. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] FIG1 is a schematic diagram of a cold hydrogenation production system provided in an embodiment of the present application;

[0020] FIG2 is a schematic diagram of a fourth heat exchange device in a cold hydrogenation production system provided in an embodiment of the present application;

[0021] FIG3 is a schematic diagram of an absorption refrigeration device in a cold hydrogenation production system provided in an embodiment of the present application;

[0022] In the figure: 1-silicon powder feed pipeline; 2-catalyst feed pipeline; 3-cold hydrogenation reaction device; 4-first heat exchange device; 5-gas-solid separation device; 6-second heat exchange device; 7-first mixing device; 8-hydrogen chloride storage device; 9-hydrogen storage device; 10-third heat exchange device; 11-silicon tetrachloride storage device; 12-heating device; 13-second mixing device; 14-washing device; 15-chlorosilane washing liquid discharge pipeline; 16-slurry discharge pipeline; 17-absorption refrigeration device; 18-refrigerated circulating water pipeline; 19-chilled water pipeline; 20-first heating water supply pipeline (from the user); 21- First heating return water pipeline (to the user); 22-organic Rankine cycle device; 23-power generation device; 24-heating device; 25-second heating water supply pipeline (from the user); 26-second heating return water pipeline (to the user); 27-gas-liquid separation device; 28-chlorosilane washing liquid pipeline; 29-chlorosilane liquid discharge pipeline; 30-first gas recovery pipeline; 31-fourth heat exchange device; 32-first condenser; 33-second gas recovery pipeline; 34-distillation unit pipeline; 171-generator; 172-second condenser; 173-evaporator; 174-absorber; 175-fifth heat exchange device. DETAILED DESCRIPTION

[0023] The technical solution of the present application will be described below with reference to the accompanying drawings and through implementation methods.

[0024] In the cold hydrogenation method, the catalyst, silicon powder, silicon tetrachloride and hydrogen are introduced into a fluidized bed to generate trichlorosilane at a reaction temperature of 500-600°C. The reaction equation is as follows: Si+3SiCl4+2H2=4SiHCl3.

[0025] The cold hydrogenation reaction described above is an endothermic process, requiring a large amount of heat during the reaction. Currently, the reaction temperature is primarily maintained by electric heaters, which results in excessively high electricity costs. Furthermore, the waste of excess heat from the reaction results in energy loss, which is inconsistent with national energy conservation and emission reduction requirements. Furthermore, in actual production, the single-pass conversion rate of silicon tetrachloride is only 20-25%, significantly lower than the single-pass conversion rate achieved in the laboratory. Therefore, rationally utilizing the heat generated during the reaction and increasing the conversion rate of silicon tetrachloride to trichlorosilane are key to reducing production costs and expanding production scale for polysilicon companies.

[0026] The embodiments of the present application provide a cold hydrogenation production system, which utilizes the waste heat of the cold hydrogenation reaction products through cascade heat exchange and recycles hydrogen chloride, hydrogen, etc., thereby saving resources and improving the utilization rate of reactants.

[0027] The system includes a cold hydrogenation reaction device 3, a first heat exchange device 4, a gas-solid separation device 5, a second heat exchange device 6 and a third heat exchange device 10 connected in sequence;

[0028] The material outlet of the cold hydrogenation reaction device 3 is connected to the heat medium inlet of the first heat exchange device 4, the heat medium outlet of the first heat exchange device 4 is connected to the material inlet of the gas-solid separation device 5, and the cold medium outlet of the first heat exchange device 4 is connected to the cold hydrogenation reaction device 3;

[0029] The gas outlet of the gas-solid separation device 5 is connected to the heat medium inlet of the second heat exchange device 6, and the solid outlet of the gas-solid separation device 5 is connected to the cold hydrogenation reaction device 3;

[0030] The cold medium inlet of the second heat exchange device 6 is connected to the material outlet of the first mixing device 7, the cold medium outlet of the second heat exchange device 6 is connected to the second mixing device 13, and the material outlet of the second mixing device 13 is connected to the cold medium inlet of the first heat exchange device 4;

[0031] The hot medium outlet of the second heat exchange device 6 is connected to the hot medium inlet of the third heat exchange device 10, the cold medium inlet of the third heat exchange device 10 is connected to the material outlet of the silicon tetrachloride storage device 11, the cold medium outlet of the third heat exchange device 10 is connected to the material inlet of the heating device 12, and the material outlet of the heating device 12 is connected to the inlet of the second mixing device 13.

[0032] In this application, the cold hydrogenation production system, through the arrangement of a first heat exchanger 4, a second heat exchanger 6, and a third heat exchanger 10, uses the gas-solid mixture produced after the reaction in the cold hydrogenation reaction unit 3 and the mixed gas obtained after separation to fully preheat the raw materials for the cold hydrogenation reaction, such as hydrogen chloride, hydrogen, chlorosilane, and silicon tetrachloride. This fully utilizes the temperature of the gaseous products themselves, reduces the amount of heat added to the reaction system, and reduces energy consumption. At the same time, after gas-solid separation, the silicon powder particles entrained in the separated products are recycled, reducing silicon loss and improving reaction efficiency.

[0033] Based on the above technical solution, the cold hydrogenation production system of the present application can use the heat in the gaseous mixture generated by the cold hydrogenation reaction as a heat source to perform multi-stage heating of silicon tetrachloride, hydrogen, hydrogen chloride, and recovered gas, fully utilizing the temperature of the gaseous product itself, reducing the heat supplement of the reaction system, and reducing energy consumption; and, the silicon powder particles in the gaseous product after the reaction are recycled to reduce silicon loss; in addition, hydrogen chloride is also used as a reactant in the cold hydrogenation reaction. This synthesis reaction is an exothermic reaction, which generates a large amount of heat, autonomously increases the temperature inside the cold hydrogenation reactor, reduces the amount of external electric heating, and thus reduces energy consumption.

[0034] The cold hydrogenation production system also includes at least one heat extraction device, which includes at least one of an absorption refrigeration device 17, an organic Rankine cycle device 22 and a heating device 24; wherein the heat extraction device is connected to the heat medium outlet of the third heat exchange device 10.

[0035] Based on the above technical solution, this application can use medium and low-grade heat as the heat source for absorption refrigeration systems, organic Rankine cycle systems, and heating heaters, scientifically and rationally realize the cascade utilization of energy, and can achieve diversified energy product output of heat, cooling, electricity, and heating.

[0036] A washing device 14 is provided between the heat extraction device and the third heat exchange device 10 .

[0037] The material outlet of the last-stage heat extraction device is connected to the material inlet of the gas-liquid separation device 27, the gas outlet of the gas-liquid separation device 27 is connected to the first mixing device 7 through the first gas recovery pipeline 30, and the liquid outlet of the gas-liquid separation device 27 is connected to the washing liquid inlet of the washing device 14.

[0038] Based on the above technical solution, the gas product is separated and reused by the gas-liquid separation device, which is beneficial to saving resources and improving the utilization rate of the reactants; in addition, the excess hydrogen is conducive to the reaction moving towards the production of trichlorosilane, which is beneficial to improving the yield of trichlorosilane and the recovery and utilization of silicon tetrachloride.

[0039] The outlet of the gas-liquid separation device 27 leads to a chlorosilane liquid discharge pipeline 29. This chlorosilane liquid discharge pipeline 29 and the washing liquid pipeline at the outlet of the scrubbing device 14 are connected to the heat medium inlet of the fourth heat exchange device 31. The heat medium outlet of the fourth heat exchange device 31 is connected to the inlet of the first condenser 32. Chilled water circulates between the absorption refrigeration device 17 and the fourth heat exchange device 31 via the refrigerated circulating water pipeline 18. Furthermore, the gas outlet of the first condenser 32 is connected to the first mixing device 7 via a second gas recovery pipeline 33, and the liquid outlet of the first condenser 32 is connected to the distillation unit pipeline 34. This chlorosilane liquid discharge pipeline 29 and the chlorosilane washing liquid pipeline 28 at the outlet of the scrubbing device 14 are connected to the heat medium inlet of the fourth heat exchange device 31.

[0040] The chilled water discharged from the outlet of the absorption refrigeration device enters the fourth heat exchange device from the cold medium inlet of the fourth heat exchange device, undergoes heat exchange, and then returns to the inlet of the absorption refrigeration device from the cold medium outlet of the fourth heat exchange device.

[0041] Based on the above technical solution, the present application uses the chilled water generated by the absorption refrigeration device as a cold source to exchange heat and cool the product chlorosilane, thereby reducing energy consumption and improving energy utilization. Unreacted hydrogen chloride, hydrogen and other gases are recycled and reused, saving resources and improving the utilization rate of reactants. In addition, excess hydrogen is conducive to the reaction moving in the direction of producing trichlorosilane, which is beneficial to improving the yield of trichlorosilane and the recycling of silicon tetrachloride.

[0042] In one embodiment of the present application, the heat extraction device may be an absorption refrigeration device 17 , an organic Rankine cycle device 22 , and a heating device 24 connected in sequence.

[0043] In one embodiment of the present application, the cold medium inlet of the absorption refrigeration device 17 is connected to the refrigerated circulating water pipeline 18 and the first heating water supply pipeline (from the user) 20, and the cold medium outlet of the absorption refrigeration device 17 is connected to the chilled water pipeline 19 and the first heating return water pipeline (to the user) 21.

[0044] In one embodiment of the present application, the absorption refrigeration device 17 may use lithium bromide and water as a working medium pair, wherein water is a refrigerant and the lithium bromide aqueous solution is an absorbent.

[0045] In one embodiment of the present application, the absorption refrigeration device 17 includes a generator 171, a second condenser 172, an evaporator 173, an absorber 174, and a fifth heat exchange device 175. The heat medium inlet of the generator 171 is connected to the scrubbing device 14, and the gaseous mixture from the scrubbing device 14 is introduced. The heat medium outlet of the generator 171 is connected to the organic Rankine cycle device 22. The water vapor outlet of the generator 171 is connected to the water vapor inlet of the second condenser 172. The aqueous solution outlet of the generator 171 is connected to the fifth heat exchange device 175. The medium-temperature water outlet of the second condenser 172 is connected to the medium-temperature water inlet of the evaporator 173. The water vapor outlet of the evaporator 173 is connected to the absorber 174. The chilled water outlet of 173 is connected to the fourth heat exchange device 31, and the chilled circulating water inlet of the evaporator 173 is connected to the fourth heat exchange device 31; the aqueous solution outlet of the absorber 174 is connected to the fifth heat exchange device 175, and the cooling water inlet of the absorber 174 is connected to the heating water from the user. The cooling water outlet of the absorber 174 is connected to the second condenser 172 to pass the heating water in the absorber 174 into the second condenser 172. The heating water outlet of the second condenser 172 is connected to the user to provide heating return water to the user.

[0046] The generator 171 receives the medium-temperature gas phase mixture from the washing device 14. The working medium solution in the generator 171 is heated by the medium-temperature gas phase mixture, wherein the water is vaporized into water vapor and enters the second condenser 172, condensed into water, and the concentration of the lithium bromide aqueous solution remaining in the generator 171 increases, and enters the absorber 174 through the fifth heat exchange device 175. The water condensed in the second condenser 172 enters the evaporator 173 and rapidly expands and is vaporized into water vapor. The water vapor enters the absorber 174 and is absorbed by the lithium bromide aqueous solution in the absorber 174. The low-concentration lithium bromide aqueous solution formed passes through the fifth heat exchange device 175 and enters the generator 171, completing the absorption refrigeration cycle process; the heating water from the user enters the absorber 174, and the temperature increases after heat exchange with the low-concentration lithium bromide aqueous solution, and enters the second condenser 1 72 is further heated up after heat exchange with the water vapor from the generator 171, and hot water is formed and connected to the user to provide heating return water; the refrigerated circulating water from the fourth heat exchange device 31 enters the evaporator 173, and the medium-temperature water in the evaporator 173 absorbs a large amount of heat from the refrigerated circulating water when it rapidly expands and vaporizes into water vapor, so that the temperature of the refrigerated circulating water is reduced. The refrigerated water with reduced temperature enters the fourth heat exchange device 31 and exchanges heat with the chlorosilane coming out of the washing device 14 and the gas-liquid separation device 27, thereby reducing the temperature of the chlorosilane; the medium-temperature gas mixture is cooled after passing through the generator 171 and becomes a low-temperature gas-liquid mixture, which is discharged from the gas-liquid outlet of the generator 171 and enters the organic Rankine cycle device 22; the lithium bromide aqueous solution coming out of the generator 171 and the lithium bromide aqueous solution coming out of the absorber 174 are heat-exchanged through the fifth heat exchange device 175.

[0047] In one embodiment of the present application, the organic Rankine cycle device 22 is connected to a power generation device 23 .

[0048] In one embodiment of the present application, the cold medium inlet of the heating device 24 is connected to the second heating water supply pipeline (from the user) 25, and the cold medium outlet of the heating device 24 is connected to the second heating return water pipeline (to the user) 26.

[0049] In the present application, the heat medium of the third heat exchange device 10, that is, the mixed gas after preheating silicon tetrachloride, is further heated after washing, that is, the waste heat is recovered through the absorption refrigeration device 17, the organic Rankine cycle device 22 and the heating device 24, thereby scientifically and rationally realizing the cascade utilization of energy and completing the output of diversified energy products such as heat, cold, electricity and heating.

[0050] The embodiments of the present application provide a cold hydrogenation production process, which uses the above-mentioned cold hydrogenation production system. The production process includes:

[0051] After mixing hydrogen chloride, hydrogen and chlorosilane, a first preheating is performed;

[0052] performing a second preheating on silicon tetrachloride, and heating the silicon tetrachloride after the second preheating;

[0053] The heated silicon tetrachloride is mixed with the hydrogen chloride, hydrogen and chlorosilane after the first preheating, and then subjected to a third preheating and a cold hydrogenation reaction to obtain a gas-solid mixture;

[0054] The gas-solid mixture is used for the third preheating and then undergoes gas-solid separation. The obtained solid is returned for cold hydrogenation reaction, and the obtained gas is sequentially used for the first preheating and the second preheating.

[0055] The cold hydrogenation production process also includes: washing the gas after the third preheating and using it for heat extraction, and the heat extraction includes at least one of absorption refrigeration, organic Rankine cycle, and heating.

[0056] The production process also includes: washing the gas after the second preheating and using it for heat extraction, and the heat extraction includes at least one of absorption refrigeration, organic Rankine cycle, and heating.

[0057] The cold hydrogenation production process also includes: performing gas-liquid separation on the gas-liquid mixture after heat removal, mixing the obtained gas with hydrogen chloride, hydrogen and chlorosilane, and performing a first preheating; and recycling the obtained liquid for washing.

[0058] In one embodiment of the present application, the cold hydrogenation reaction is 2SiCl4+H2+Si+HCl→3SiHCl3. Compared with the synthesis of trichlorosilane without hydrogen chloride, this synthesis method has a lower reaction temperature and is an exothermic reaction, which can reduce the energy consumption of the synthesis of trichlorosilane in the present application.

[0059] In one embodiment of the present application, the cold hydrogenation reaction temperature is 500-600°C, and the reaction pressure is 2.5-3.8 MPa. The reaction temperature can be 500°C, 510°C, 520°C, 530°C, 540°C, 550°C, 560°C, 570°C, 580°C, 590°C, or 600°C, and the reaction pressure can be 2.5 MPa, 2.8 MPa, 3.0 MPa, 3.2 MPa, 3.5 MPa, or 3.8 MPa, but are not limited to the values ​​listed above. Other values ​​not listed within the above numerical ranges are also applicable.

[0060] In one embodiment of the present application, the temperature of the hydrogen chloride, hydrogen, and chlorosilane (which may also include recycled gas) after the first preheating may be 240-270°C, and the pressure may be 2.5-3.8 MPa. The temperature may be 240°C, 245°C, 250°C, 255°C, 260°C, 265°C, or 270°C, and the pressure may be 2.5 MPa, 2.8 MPa, 3.0 MPa, 3.2 MPa, 3.5 MPa, or 3.8 MPa, but the values ​​listed are not limited thereto. Other values ​​not listed within the above numerical ranges are also applicable.

[0061] In one embodiment of the present application, the temperature of the silicon tetrachloride after the second preheating and heating is 240-270°C, and the pressure is 2.5-3.8 MPa. The temperature may be 240°C, 245°C, 250°C, 255°C, 260°C, 265°C, or 270°C, and the pressure may be 2.5 MPa, 2.8 MPa, 3.0 MPa, 3.2 MPa, 3.5 MPa, or 3.8 MPa, but are not limited to the values ​​listed above. Other values ​​not listed within the above numerical ranges are also applicable.

[0062] In one embodiment of the present application, the temperature of the mixed gas of hydrogen chloride, hydrogen, and silicon tetrachloride (which may also include recycled gas) after the third preheating is 390-420°C, and the pressure is 2.5-3.8 MPa. The temperature may be 390°C, 395°C, 400°C, 405°C, 410°C, 415°C, or 420°C, and the pressure may be 2.5 MPa, 2.8 MPa, 3.0 MPa, 3.2 MPa, 3.5 MPa, or 3.8 MPa, but are not limited to the values ​​listed above. Other values ​​not listed within the above numerical ranges are also applicable.

[0063] In one embodiment of the present application, the gas-solid mixture produced by the cold hydrogenation reaction has a temperature of 440-480°C and a pressure of 2.5-3.8 MPa after the third preheating. The temperature may be 440°C, 445°C, 450°C, 455°C, 460°C, 465°C, 470°C, 475°C, or 480°C, and the pressure may be 2.5 MPa, 2.8 MPa, 3.0 MPa, 3.2 MPa, 3.5 MPa, or 3.8 MPa, but are not limited to the values ​​listed above. Other values ​​not listed within the above numerical ranges are also applicable.

[0064] In one embodiment of the present application, the temperature of the mixed gas after gas-solid separation is 400-440°C, and the pressure is 2.5-3.8 MPa. The temperature may be 400°C, 405°C, 410°C, 415°C, 420°C, 425°C, 430°C, 435°C, or 440°C, and the pressure may be 2.5 MPa, 2.8 MPa, 3.0 MPa, 3.2 MPa, 3.5 MPa, or 3.8 MPa, but are not limited to the values ​​listed above. Other values ​​not listed within the above numerical ranges are also applicable.

[0065] In one embodiment of the present application, the temperature of the mixed gas after the first preheating is 300-340°C, and the pressure is 2.5-3.8 MPa. The temperature may be 300°C, 305°C, 310°C, 315°C, 320°C, 325°C, 330°C, 335°C, or 340°C, and the pressure may be 2.5 MPa, 2.8 MPa, 3.0 MPa, 3.2 MPa, 3.5 MPa, or 3.8 MPa, but the values ​​listed are not limited thereto. Other values ​​not listed within the above ranges are also applicable.

[0066] In one embodiment of the present application, the temperature of the mixed gas after the second preheating is 220-260°C, and the pressure is 2.5-3.8 MPa. The temperature may be 220°C, 225°C, 230°C, 235°C, 240°C, 245°C, 250°C, 255°C, or 260°C, and the pressure may be 2.5 MPa, 2.8 MPa, 3.0 MPa, 3.2 MPa, 3.5 MPa, or 3.8 MPa, but the values ​​listed are not limited thereto. Other values ​​not listed within the above ranges are also applicable.

[0067] In one embodiment of the present application, the temperature of the gas mixture after being scrubbed by the scrubbing device 14 is 190-230°C, and the pressure is 2.5-3.8 MPa. The temperature may be 190°C, 195°C, 200°C, 205°C, 210°C, 215°C, 220°C, 225°C, or 230°C, and the pressure may be 2.5 MPa, 2.8 MPa, 3.0 MPa, 3.2 MPa, 3.5 MPa, or 3.8 MPa, but the values ​​listed are not limited thereto. Other values ​​not listed within the above numerical ranges are also applicable.

[0068] In one embodiment of the present application, the temperature of the gas-liquid mixture after passing through the absorption refrigeration device 17 is 140-180°C, and the pressure is 2.5-3.8 MPa. The temperature may be 140°C, 145°C, 150°C, 155°C, 160°C, 165°C, 170°C, 175°C, or 180°C, and the pressure may be 2.5 MPa, 2.8 MPa, 3.0 MPa, 3.2 MPa, 3.5 MPa, or 3.8 MPa, but the values ​​listed are not limited thereto. Other values ​​within the above ranges are also applicable.

[0069] In one embodiment of the present application, the temperature of the gas-liquid mixture after passing through the organic Rankine cycle device 22 is 90-130°C, and the pressure is 2.5-3.8 MPa. The temperature may be 90°C, 95°C, 100°C, 105°C, 110°C, 115°C, 120°C, 125°C, or 130°C, and the pressure may be 2.5 MPa, 2.8 MPa, 3.0 MPa, 3.2 MPa, 3.5 MPa, or 3.8 MPa, but the values ​​listed are not limited thereto. Other values ​​within the above ranges are also applicable.

[0070] In one embodiment of the present application, the temperature of the gas-liquid mixture after passing through the heating device 24 is 50-90°C, and the pressure is 2.5-3.8 MPa. The temperature may be 50°C, 55°C, 60°C, 65°C, 70°C, 75°C, 80°C, 85°C, or 90°C, and the pressure may be 2.5 MPa, 2.8 MPa, 3.0 MPa, 3.2 MPa, 3.5 MPa, or 3.8 MPa, but the values ​​listed are not limited thereto. Other values ​​not listed within the above ranges are also applicable.

[0071] In one embodiment of the present application, after the gas-liquid mixture undergoes gas-liquid separation, a portion returns to the scrubbing device 14, and a portion enters the fourth heat exchange device 31. The liquid entering the fourth heat exchange device 31 has a temperature of 50 to 90°C and a pressure of 2.5 to 3.8 MPa. The temperature may be 50°C, 55°C, 60°C, 65°C, 70°C, 75°C, 80°C, 85°C, or 90°C, and the pressure may be 2.5 MPa, 2.8 MPa, 3.0 MPa, 3.2 MPa, 3.5 MPa, or 3.8 MPa, but the values ​​listed are not limited thereto. Other values ​​not listed within the above numerical ranges are also applicable.

[0072] In one embodiment of the present application, the washing liquid and a portion after gas-liquid separation are heat exchanged and cooled with chilled water produced by the absorption refrigeration device 17 in the fourth heat exchange device 31. The gas-liquid mixture at the outlet enters the first condenser 32 at a temperature of 20 to 60°C and a pressure of 2.5 to 3.8 MPa. The temperature can be 20°C, 25°C, 30°C, 35°C, 40°C, 45°C, 50°C, 55°C, or 60°C, and the pressure can be 2.5 MPa, 2.8 MPa, 3.0 MPa, 3.2 MPa, 3.5 MPa, or 3.8 MPa, but are not limited to the listed values. Other values ​​not listed within the above numerical ranges are also applicable.

[0073] In one embodiment of the present application, the gas-liquid mixture after heat exchange in the fourth heat exchange device 31 enters the first condenser 32. The temperature of the mixture at the outlet of the first condenser 32 is -20 to 20°C, and the pressure is 2.5 to 3.8 MPa. The uncondensed gas phase enters the first gas recovery pipeline 30, and the condensed liquid phase enters the distillation unit pipeline 34. The temperature can be -20°C, -15°C, -5°C, 0°C, 5°C, 10°C, 15°C, or 20°C, and the pressure can be 2.5 MPa, 2.8 MPa, 3.0 MPa, 3.2 MPa, 3.5 MPa, or 3.8 MPa, but are not limited to the listed values. Other values ​​not listed within the above numerical ranges are also applicable.

[0074] To illustrate the present application and facilitate understanding of the technical solution of the present application, the embodiments of the present application are as follows:

[0075] Example 1

[0076] This embodiment provides a cold hydrogenation production system, which includes a cold hydrogenation reaction device 3, a first heat exchange device 4, a gas-solid separation device 5, a second heat exchange device 6 and a third heat exchange device 10 connected in sequence;

[0077] The material outlet of the cold hydrogenation reaction device 3 is connected to the heat medium inlet of the first heat exchange device 4, the heat medium outlet of the first heat exchange device 4 is connected to the material inlet of the gas-solid separation device 5, and the cold medium outlet of the first heat exchange device 4 is connected to the cold hydrogenation reaction device 3;

[0078] The gas outlet of the gas-solid separation device 5 is connected to the heat medium inlet of the second heat exchange device 6, and the solid outlet of the gas-solid separation device 5 is connected to the cold hydrogenation reaction device 3;

[0079] The cold medium inlet of the second heat exchange device 6 is connected to the material outlet of the first mixing device 7, the cold medium outlet of the second heat exchange device 6 is connected to the second mixing device 13, and the material outlet of the second mixing device 13 is connected to the cold medium inlet of the first heat exchange device 4;

[0080] The hot medium outlet of the second heat exchange device 6 is connected to the hot medium inlet of the third heat exchange device 10, the cold medium inlet of the third heat exchange device 10 is connected to the material outlet of the silicon tetrachloride storage device 11, the cold medium outlet of the third heat exchange device 10 is connected to the material inlet of the heating device 12, and the material outlet of the heating device 12 is connected to the inlet of the second mixing device 13.

[0081] Example 2

[0082] This embodiment provides a cold hydrogenation production system, the structure of which is shown in FIG1 . The system includes a cold hydrogenation reaction device 3 , a first heat exchange device 4 , a gas-solid separation device 5 , a second heat exchange device 6 , and a third heat exchange device 10 , which are connected in sequence.

[0083] The material outlet of the cold hydrogenation reaction device 3 is connected to the heat medium inlet of the first heat exchange device 4, the heat medium outlet of the first heat exchange device 4 is connected to the material inlet of the gas-solid separation device 5, and the cold medium outlet of the first heat exchange device 4 is connected to the cold hydrogenation reaction device 3; the material inlet of the cold hydrogenation reaction device 3 is connected to the silicon powder feed pipeline 1 and the catalyst feed pipeline 2;

[0084] The gas outlet of the gas-solid separation device 5 is connected to the heat medium inlet of the second heat exchange device 6, and the solid outlet of the gas-solid separation device 5 is connected to the cold hydrogenation reaction device 3;

[0085] The cold medium inlet of the second heat exchange device 6 is connected to the material outlet of the first mixing device 7, and the cold medium outlet of the second heat exchange device 6 is connected to the second mixing device 13, and the material outlet of the second mixing device 13 is connected to the cold medium inlet of the first heat exchange device 4; the material inlet of the first mixing device 7 is connected to the hydrogen chloride storage device 8 and the hydrogen storage device 9, and the material inlet of the first mixing device 7 is also connected to the chlorosilane liquid discharge pipeline 29 and the first gas recovery pipeline 30;

[0086] The hot medium outlet of the second heat exchange device 6 is connected to the hot medium inlet of the third heat exchange device 10, the cold medium inlet of the third heat exchange device 10 is connected to the material outlet of the silicon tetrachloride storage device 11, the cold medium outlet of the third heat exchange device 10 is connected to the material inlet of the heating device 12, and the material outlet of the heating device 12 is connected to the second mixing device 13;

[0087] A scrubbing device 14 and at least one stage of heat extraction device are sequentially provided between the third heat exchange device 10 and the first gas recovery pipeline 30;

[0088] The heat extraction device includes an absorption refrigeration device 17, an organic Rankine cycle device 22, and a heating device 24 connected in sequence. The heat medium outlet of the heating device 24 is connected to the material inlet of the gas-liquid separation device 27. The gas outlet of the gas-liquid separation device 27 is connected to the first gas recovery pipeline 30. The liquid outlet of the gas-liquid separation device 27 is connected to the washing liquid inlet of the washing device 14.

[0089] The washing device 14 is connected to the chlorosilane washing liquid discharge pipeline 15 and the slurry discharge pipeline 16, the cold medium inlet of the absorption refrigeration device 17 is connected to the refrigerated circulating water pipeline 18 and the first heating water supply pipeline (from the user) 20, and the cold medium outlet of the absorption refrigeration device 17 is connected to the chilled water pipeline 19 and the first heating return water pipeline (to the user) 21; the organic Rankine cycle device 22 is connected to the power generation device 23, the cold medium inlet of the heating device 24 is connected to the second heating water supply pipeline (from the user) 25, and the cold medium outlet of the heating device 24 is connected to the second heating return water pipeline 26 (to the user).

[0090] Example 3

[0091] This embodiment provides a cold hydrogenation production system, which has the same structure as that of Embodiment 2 except for including a fourth heat exchange device 31 , as shown in FIG2 .

[0092] The hot medium inlet of the fourth heat exchange device 31 is connected to the chlorosilane washing liquid discharge pipeline 15 of the washing device 14 and the chlorosilane liquid discharge pipeline 29 of the gas-liquid separation device 27; the hot medium outlet of the fourth heat exchange device 31 is connected to the first condenser 32, the cold medium inlet of the fourth heat exchange device 31 is connected to the chilled water pipeline 19 of the absorption refrigeration device 17, and the cold medium outlet of the fourth heat exchange device 31 is connected to the refrigerated circulating water pipeline 18 of the absorption refrigeration device 17; the gas outlet of the first condenser 32 is connected to the second gas recovery pipeline 33 and the distillation unit pipeline 34.

[0093] Example 4

[0094] This embodiment provides a cold hydrogenation production system, the structure of which is the same as that of embodiment 2, except that the structure of the absorption refrigeration device 17 is shown in FIG3 ;

[0095] The absorption refrigeration device 17 includes a generator 171, a second condenser 172, an evaporator 173, an absorber 174 and a fifth heat exchange device 175;

[0096] The heat medium inlet of the generator 171 is connected to the scrubbing device 14, and the heat medium outlet is connected to the organic Rankine cycle device 22 to pass the gas-liquid mixture into the organic Rankine cycle device 22. The cold medium inlet is connected to the fifth heat exchange device 175, and the cold medium vapor outlet and liquid outlet are connected to the heat medium inlet of the second condenser 172 and the fifth heat exchange device 175, respectively.

[0097] The heat medium inlet of the second condenser 172 is connected to the cold medium outlet of the generator 171 , the heat medium outlet is connected to the heat medium inlet of the evaporator 173 , and the cold medium inlet is connected to the absorber 174 ;

[0098] The hot medium outlet of the evaporator 173 is connected to the hot medium inlet of the absorber 174, and the cold medium inlet and the cold medium outlet are connected to the fourth heat exchange device 31, forming a chilled water cycle;

[0099] The hot medium outlet of the absorber 174 is connected to the fifth heat exchange device 175, and the cold medium outlet is connected to the second condenser 172;

[0100] The fifth heat exchange device 175 is connected to the generator 171 and the absorber 174 .

[0101] Example 5

[0102] This embodiment provides a cold hydrogenation production process, using the cold hydrogenation production system provided in Example 4. The production process includes the following steps:

[0103] 1) Hydrogen chloride, excess hydrogen, and recycled gas are mixed in a first mixing device 7, and then preheated in a second heat exchange device 6. The preheated mixture of hydrogen chloride, hydrogen, and recycled gas has a temperature of 240-270°C and a pressure of 2.5-3.8 MPa.

[0104] 2) The silicon tetrachloride liquid is passed into the third heat exchange device 10 for a second preheating, and then the silicon tetrachloride is heated by the heating device 12 until it is completely vaporized. The temperature of the vaporized silicon tetrachloride is 240-270° C. and the pressure is 2.5-3.8 MPa.

[0105] 3) The hydrogen chloride, hydrogen, recovered gas, and silicon tetrachloride gas are mixed by the second mixing device 13 and then preheated by the first heat exchange device 4. The preheated mixed gas of hydrogen chloride, hydrogen, recovered gas, and silicon tetrachloride has a temperature of 390-420° C. and a pressure of 2.5-3.8 MPa.

[0106] 4) The preheated hydrogen chloride, hydrogen, recycled gas, and silicon tetrachloride mixed gas are introduced into a cold hydrogenation reaction unit 3, where they are mixed with a catalyst and excess silicon powder to undergo a cold hydrogenation reaction at a temperature of 530-580° C. and a pressure of 2.5-3.8 MPa. The reaction product is a gaseous mixture whose main components are dichlorosilane, trichlorosilane, hydrogen, hydrogen chloride, silicon powder, and silicon tetrachloride. The main reaction of the cold hydrogenation reaction is 2SiCl4+H2+Si+HCl→3SiHCl3, and the single-pass yield of trichlorosilane is 32%.

[0107] 5) The gas-solid mixture generated in step 4) is passed into the first heat exchange device 4 for heat exchange with the mixed gas of hydrogen chloride, hydrogen, recovered gas and silicon tetrachloride in step 3), and the temperature of the gas phase mixture after heat exchange is 440-480° C. and the pressure is 2.5-3.8 MPa.

[0108] 6) The gas-solid mixture after the heat exchange in step 5) is passed into a gas-solid separation device 5 for gas-solid separation. The separated solid is discharged from the bottom of the gas-solid separation device 5 and re-enters the cold hydrogenation reaction device 3 for cold hydrogenation reaction. The temperature of the separated gas phase mixture is 400-440° C. and the pressure is 2.5-3.8 MPa.

[0109] 7) The gaseous mixture separated in step 6) is passed into a second heat exchange device 6 for heat exchange with the hydrogen chloride, hydrogen, and recovered gas mixture in step 1). The temperature of the gaseous mixture after heat exchange is 300-340° C. and the pressure is 2.5-3.8 MPa.

[0110] 8) The gaseous mixture after heat exchange in step 7) is passed into a third heat exchange device 10 for heat exchange with the silicon tetrachloride liquid in step 2). The temperature of the gaseous mixture after heat exchange is 220-260° C. and the pressure is 2.5-3.8 MPa.

[0111] 9) The gaseous mixture after heat exchange in step 8) is passed into the washing device 14, and the washing liquid is recovered and enters the fourth heat exchange device 31. The slurry is discharged from the bottom of the washing device 14. The outlet temperature of the gaseous mixture is 190-230°C and the pressure is 2.5-3.8 MPa.

[0112] 10) The gaseous mixture exiting the scrubbing unit 14 in step 9) is passed into an absorption refrigeration unit 17 for heat exchange. After heat exchange and cooling, the gaseous mixture forms a gas-liquid mixture with an outlet temperature of 140-180°C and a pressure of 2.5-3.8 MPa. Simultaneously, the absorption refrigeration unit 17 produces chilled water and heating water.

[0113] 11) The gas-liquid mixture flowing out of the absorption refrigeration device 17 in step 10) is passed into the organic Rankine cycle device 22 to generate electricity using the waste heat of the gas-liquid mixture. The outlet gas-liquid mixture has a temperature of 90-130° C. and a pressure of 2.5-3.8 MPa.

[0114] 12) The gas-liquid mixture flowing out of the organic Rankine cycle device 22 in step 11) is passed into the heating device 24 to provide heating using the waste heat of the gas-liquid mixture. The outlet temperature of the gas-liquid mixture is 50-90° C. and the pressure is 2.5-3.8 MPa.

[0115] 13) The gas-liquid mixture flowing out of the heating device 24 in step 12) is passed into the gas-liquid separation device 27, the gas is recovered and enters the first mixing device 7, part of the liquid enters the washing device 14, and part enters the fourth heat exchange device 31. The temperature of the liquid entering the fourth heat exchange device 31 is 50-90°C and the pressure is 2.5-3.8 MPa.

[0116] 14) The washing liquid in step 9) and the liquid in step 13) are passed into the fourth heat exchange device 31 for heat exchange and cooling with the chilled water produced by the absorption refrigeration device 17 in step 10), and the gas-liquid mixture at the outlet enters the first condenser 32 with a temperature of 20-60°C and a pressure of 2.5-3.8 MPa.

[0117] The gas-liquid mixture flowing out of the fourth heat exchange device 31 in step 14) is passed into the first condenser 32. The temperature of the mixture at the outlet of the first condenser 32 is -20 to 20°C and the pressure is 2.5 to 3.8 MPa. The uncondensed gas phase enters the first mixing device 7 through the first gas recovery pipeline 30, and the condensed liquid phase enters the distillation unit pipeline 34.

[0118] The cold hydrogenation production system in the embodiment recycles the silicon powder particles in the gas phase product after the reaction, thereby reducing silicon loss; hydrogen chloride is used as a reactant to participate in the cold hydrogenation reaction, and this synthesis reaction is an exothermic reaction, which generates a large amount of heat, thereby autonomously increasing the temperature in the cold hydrogenation reaction device, reducing the amount of external electric heating, and thus reducing energy consumption; the heat in the gas phase mixture generated by the cold hydrogenation reaction is used as a heat source to perform multi-stage heating of silicon tetrachloride, hydrogen, hydrogen chloride, and recovered gas, thereby making full use of the temperature of the gas phase product itself, reducing the amount of heat added to the reaction system, and reducing energy consumption; utilizing medium and low-grade heat As a heat source for absorption refrigeration devices, organic Rankine cycle devices, and heating devices, it scientifically and rationally realizes the cascade utilization of energy and completes the output of diversified energy products such as heat, cooling, electricity, and heating; the chilled water produced by the absorption refrigeration device is used as a cold source to exchange heat and cool the product chlorosilane, reducing energy consumption and improving energy utilization; the unreacted hydrogen chloride, hydrogen and other gases are recycled and reused, saving resources and improving the utilization rate of reactants; excess hydrogen is conducive to the reaction moving in the direction of producing trichlorosilane, which is beneficial to increasing the yield of trichlorosilane and the recycling of silicon tetrachloride.

[0119] This application has the following effects:

[0120] (1) The present application provides a cold hydrogenation production system and production process, which can recycle silicon powder particles entrained in the gas phase product after the reaction, thereby reducing silicon loss and improving reaction efficiency;

[0121] (2) The present application provides a cold hydrogenation production system and production process, which uses high-purity hydrogen chloride gas as a reactant in a cold hydrogenation reaction. This synthesis reaction is exothermic and generates a large amount of heat, which autonomously increases the temperature within the reactor and reduces the amount of external electrical heating, thereby reducing energy consumption. In addition, the addition of hydrogen chloride increases the conversion rate of silicon tetrachloride to trichlorosilane;

[0122] (3) The present application provides a cold hydrogenation production system and production process, which uses the heat in the gaseous mixture produced by the cold hydrogenation reaction as a heat source to perform multi-stage heating of hydrogen, hydrogen chloride, recovered gas and silicon tetrachloride, making full use of the temperature of the gaseous product itself, reducing the amount of heat added to the reaction system and reducing energy consumption;

[0123] (4) The present application provides a cold hydrogenation production system and production process, which realizes the cascade utilization of energy. After the gaseous mixture produced by the cold hydrogenation reaction is used as a high-temperature heat source to perform multi-stage heat exchange on hydrogen, hydrogen chloride recovery gas and silicon tetrachloride, it is then used as a medium- and low-temperature heat source to sequentially recover waste heat through an absorption refrigeration device (refrigeration, heating and heat supply), organic Rankine cycle power generation and heating heater heating and heat supply, thereby scientifically and rationally realizing the cascade utilization of energy and completing the output of diversified energy products such as heat, cold, electricity and heating;

[0124] (5) The present application provides a cold hydrogenation production system and production process, which uses the chilled water produced by absorption refrigeration as a cold source to exchange heat and cool the mixture of hydrogen, hydrogen chloride and chlorosilane, thereby reducing energy consumption and improving energy utilization;

[0125] (6) The present application provides a cold hydrogenation production system and production process, which can recycle hydrogen chloride, hydrogen and unliquefied chlorosilane gas, saving resources and improving the utilization rate of reactants.

[0126] The above describes the optional implementation methods of the present application. However, the present application is not limited to the details of the above implementation methods. Within the technical concept of the present application, various simple modifications can be made to the technical solution of the present application, and these simple modifications all fall within the scope of protection of the present application.

[0127] The multiple technical features described in the above embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this application will not further explain the various possible combinations.

[0128] In addition, the various implementations of the present application may be arbitrarily combined, and as long as they do not violate the concept of the present application, they should also be regarded as the contents disclosed in the present application.

Claims

1. A cold hydrogeneration production system, the system comprising a cold hydrogeneration reaction device, a first heat exchange device, a gas-solid separation device, a second heat exchange device, and a third heat exchange device connected in sequence; The material outlet of the cold hydrogeneration reaction device is connected to the hot medium inlet of the first heat exchange device, the hot medium outlet of the first heat exchange device is connected to the material inlet of the gas-solid separation device, and the cold medium outlet of the first heat exchange device is connected to the cold hydrogeneration reaction device; The gas outlet of the gas-solid separation device is connected to the hot medium inlet of the second heat exchange device, and the solid outlet of the gas-solid separation device is connected to the cold hydrogeneration reaction device; The cold medium inlet of the second heat exchange device is connected to the material outlet of the first mixing device, the cold medium outlet of the second heat exchange device is connected to a second mixing device, and the material outlet of the second mixing device is connected to the cold medium inlet of the first heat exchange device; The hot medium outlet of the second heat exchange device is connected to the hot medium inlet of the third heat exchange device, the cold medium inlet of the third heat exchange device is connected to the material outlet of the silicon tetrachloride storage device, the cold medium outlet of the third heat exchange device is connected to the material inlet of the heating device, and the material outlet of the heating device is connected to the inlet of the second mixing device.

2. The cold hydrogenation production system according to claim 1, wherein, The cold hydrogeneration production system further comprises at least one heat extraction device, the heat extraction device comprising at least one of an absorption refrigeration device, an organic Rankine cycle device, and a heating device for heating; The heat extraction device is connected to the hot medium outlet of the third heat exchange device.

3. The cold hydrogenation production system according to claim 2, wherein, A washing device is provided between the heat extraction device and the third heat exchange device.

4. The cold hydrogenation production system according to claim 3, wherein, The material outlet of the last stage heat extraction device of the at least one heat extraction device is connected to the material inlet of the gas-liquid separation device, the gas outlet of the gas-liquid separation device is connected to the first mixing device through a first gas recovery pipeline, and the liquid outlet of the gas-liquid separation device is connected to the washing liquid inlet of the washing device.

5. The cold hydrogeneration production system according to claim 1 or 2, wherein, The material inlet of the cold hydrogeneration reaction device is connected to a silicon powder feed pipeline and a catalyst feed pipeline; The material inlet of the first mixing device is connected to a hydrogen chloride storage device and a hydrogen storage device.

6. The cold hydrogeneration production system according to claim 4, wherein, A chlorosilane liquid discharge pipeline is led out from the outlet of the gas-liquid separation device, the chlorosilane liquid discharge pipeline and the chlorosilane washing liquid pipeline at the outlet of the washing device are connected to the hot medium inlet of the fourth heat exchange device, the hot medium outlet of the fourth heat exchange device is connected to the inlet of the first condenser, and chilled water circulates between the absorption refrigeration device and the fourth heat exchange device through a chilled water circulation pipeline. The gas outlet of the first condenser is connected to the first mixing device through a second gas recovery pipeline; the liquid outlet of the first condenser is connected to a rectification unit pipeline.

7. The cold hydrogeneration production system according to claim 2, wherein, The absorption refrigeration device comprises a generator, a second condenser, an evaporator, an absorber, and a fifth heat exchange device.

8. A cold hydrogeneration production process, comprising: Mixing hydrogen chloride, hydrogen, and chlorosilane, and then performing a first preheating; Performing a second preheating on silicon tetrachloride, and vaporizing the silicon tetrachloride after the second preheating; After mixing the silicon tetrachloride after the gasification with the first preheated hydrogen chloride, hydrogen, and chlorosilane, perform a third preheating and carry out a cold hydrogenation reaction to obtain a gas-solid mixture; Use the gas-solid mixture as a heat source for the third preheating, then carry out gas-solid separation. Return the obtained solid to the cold hydrogenation reaction, and use the obtained gas as a heat source for the first preheating and the second preheating in sequence.

9. The cold hydrogeneration production process according to claim 8 further comprises: Wash the gas after the second preheating, and use the washed gas for heat extraction, where the heat extraction includes at least one of absorption refrigeration, organic Rankine cycle, or heating for heating.

10. The cold hydrogenation production process according to claim 9 further includes: Carry out gas-liquid separation on the gas-liquid mixture after heat extraction. After mixing the obtained gas with the hydrogen chloride, hydrogen, and chlorosilane, perform the first preheating, and recycle the obtained liquid to the washing.

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