A cold hydrogenation product heat recovery system
By designing a heat recovery system for cold hydrogenation products, and utilizing components such as fluidized beds, quenching components, and heat exchangers, the problem of unrecoverable heat in polysilicon production was solved, achieving efficient energy utilization and long equipment life, and reducing production costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- XINJIANG DAQO NEW ENERGY CO LTD
- Filing Date
- 2025-08-29
- Publication Date
- 2026-08-04
AI Technical Summary
In polysilicon production, during the cold hydrogenation process, some of the heat from the product cannot be recovered and utilized, resulting in energy waste. Furthermore, the distillation equipment requires steam heating, which increases production costs.
A heat recovery system for cold hydrogenation products was designed, including a fluidization component, a coarse separation component, and a heat exchange component. Through the combination of a fluidized bed, a quenching component, a reboiler, a heat exchanger, and a cooler, multi-stage heat recovery and utilization are achieved, reducing steam consumption and extending equipment service life.
The heat recovery system saves steam consumption, reduces production costs, extends the service life of the cooler, and improves energy efficiency.
Smart Images
Figure CN224585375U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the technical field of polycrystalline silicon production equipment, and in particular to a heat recovery system for cold hydrogenation products. Background Technology
[0002] Cold hydrogenation is a chemical technology that reacts hydrogen with organic compounds at low temperatures to convert unsaturated bonds into saturated bonds. In polysilicon production, cold hydrogenation is mainly used to convert silicon tetrachloride into trichlorosilane, thereby recycling byproducts. The chemical reaction formula is: 3SiCl4 + Si + 2H2 = 4SiHCl3.
[0003] Some products, such as silicon tetrachloride and trichlorosilane, still have a temperature of 120°C after cooling and condensation. They need to be cooled by circulating water before entering the distillation process. Some of the heat cannot be recovered. At the same time, some of the cold material discharged from the distillation equipment, such as silicon tetrachloride and trichlorosilane, needs to be separated in the coarse separation tower. During the separation, the cold material needs to be heated with steam, which results in energy waste. Utility Model Content
[0004] In view of this, the present invention provides a cold hydrogenation product heat recovery system, the main purpose of which is to provide a cold hydrogenation product heat recovery system that can reduce the amount of steam used and extend the service life of the cooler.
[0005] To achieve the above objectives, this utility model mainly provides the following technical solutions:
[0006] This utility model embodiment provides a heat recovery system for cold hydrogenation products, the system comprising:
[0007] A fluidizing component, comprising a fluidized bed and a quenching component, wherein the fluidized bed is connected to the quenching component;
[0008] The coarse separation component includes a coarse separation tower, a reboiler, and a loading tank. The middle part of the reboiler is connected to the quenching component, the upper end of the reboiler is connected to the coarse separation tower, and the loading tank is connected to the lower part of the reboiler.
[0009] The heat exchange component includes a distillation pipe, a first heat exchanger, and a first cooler. One end of the distillation pipe is connected to one end of the shell side of the first heat exchanger, and the other end is connected to the crude fractionation column. One end of the tube side of the first heat exchanger is connected to the loading tank, and the other end is connected to the first cooler.
[0010] Furthermore, the reboiler includes a first reboiler and a second reboiler, the quenching component is connected to the side of the first reboiler, a first connecting pipe is provided at the upper end of the first reboiler and the second reboiler, a second connecting pipe is provided at the lower end of the first reboiler and the second reboiler, the coarse separator is connected to the first connecting pipe and the second connecting pipe respectively, and the lower part of the side of the first reboiler is connected to the loading tank.
[0011] Furthermore, the quenching component includes a second heat exchanger and a quenching tower, with the upper end of the second heat exchanger connected to the fluidized bed and the lower end of the second heat exchanger connected to the quenching tower.
[0012] Furthermore, a distillation spherical tank is connected to the other end of the shell side of the first heat exchanger.
[0013] Compared with the prior art, the present invention has the following technical effects:
[0014] In the technical solution provided by this utility model embodiment, the fluidization component includes a fluidized bed and a quenching component, with the fluidized bed connected to the quenching component; the coarse separation component includes a coarse separation column, a reboiler, and a loading tank, with the middle part of the reboiler connected to the quenching component, the upper end of the reboiler connected to the coarse separation column, and the loading tank connected to the lower part of the reboiler; the heat exchange component is used to perform heat exchange treatment on the product, and includes a distillation pipe, a first heat exchanger, and a first cooler. One end of the distillation pipe is connected to one end of the shell side of the first heat exchanger, and the other end is connected to the coarse separation column. One end of the tube side of the first heat exchanger is connected to the loading tank, and the other end is connected to the first cooler. Compared with the prior art, silicon tetrachloride and trichlorosilane still have a temperature of 120°C after cooling and condensation, and then need to be cooled by circulating water before entering the distillation. Some of the heat cannot be recovered and utilized. At the same time, some of the cold material discharged from the distillation equipment needs to be further processed. The cold feed material is initially separated in the coarse fractionation tower, requiring steam heating during separation, which wastes energy. This technical solution addresses this by adding heat exchange components. The cold feed material entering the coarse fractionation tower from the distillation equipment reaches a temperature of 60 degrees Celsius. The tail gas from the fluidized bed reaction undergoes a series of heat recovery processes, followed by quenching and dust removal to obtain clean material gas. This clean gas then enters the coarse fractionation tower through a reboiler for further heat exchange and cooling. The cooled liquid material enters the loading tank, where its temperature is approximately 120 degrees Celsius. This cooled material then enters the tube side of the first heat exchanger to exchange heat with the cold feed material from the distillation equipment, raising the cold feed temperature to 80 degrees Celsius and lowering the material temperature to 90 degrees Celsius. The cold feed material then enters the coarse fractionation tower through the distillation pipeline. After further cooling in the first cooler, the material returns to the distillation equipment for further distillation. This not only saves steam used to heat the coarse fractionation tower but also extends the service life of the first cooler, thereby reducing production costs for the enterprise. Attached Figure Description
[0015] Figure 1 This is a schematic diagram of a heat recovery system for cold hydrogenation products provided in an embodiment of the present invention. Detailed Implementation
[0016] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.
[0017] like Figure 1 As shown, this utility model embodiment provides a cold hydrogenation product heat recovery system, the system comprising:
[0018] A fluidizing component, comprising a fluidized bed 11 and a quenching component, wherein the fluidized bed 11 is connected to the quenching component;
[0019] The coarse separation component includes a coarse separation tower 21, a reboiler, and a loading tank 23. The middle part of the reboiler is connected to the quenching component, the upper end of the reboiler is connected to the coarse separation tower 21, and the loading tank 23 is connected to the lower part of the reboiler.
[0020] The heat exchange component includes a distillation pipe 31, a first heat exchanger 32, and a first cooler 33. One end of the distillation pipe 31 is connected to one end of the shell side of the first heat exchanger 32, and the other end is connected to the crude fractionation column 21. One end of the tube side of the first heat exchanger 32 is connected to the loading tank 23, and the other end is connected to the first cooler 33.
[0021] In the technical solution provided by this utility model embodiment, the fluidization component includes a fluidized bed 11 and a quenching component, with the fluidized bed 11 connected to the quenching component; the coarse separation component includes a coarse separation column 21, a reboiler, and a loading tank 23, with the middle part of the reboiler connected to the quenching component, the upper end of the reboiler connected to the coarse separation column 21, and the loading tank 23 connected to the lower part of the reboiler; the heat exchange component is used to perform heat exchange treatment on the product, and includes a distillation pipe 31, a first heat exchanger 32, and a first cooler 33. One end of the distillation pipe 31 is connected to one end of the shell side of the first heat exchanger 32, and the other end is connected to the coarse separation column 21. One end of the tube side of the first heat exchanger 32 is connected to the loading tank 23, and the other end is connected to the first cooler 33. Compared with the prior art, silicon tetrachloride and trichlorosilane still have a temperature of 120°C after cooling and condensation, and then need to be cooled by circulating water before entering the distillation. Some of the heat cannot be recovered and utilized. At the same time, some of the cold water discharged from the distillation equipment is also lost. The material needs to be separated in the coarse fractionation tower 21. During separation, the cold material needs to be heated with steam, resulting in energy waste. In this technical solution, by adding heat exchange components, the temperature of the cold material entering the coarse fractionation tower 21 from the distillation equipment is 60 degrees Celsius. After the tail gas from the fluidized bed 11 reaction undergoes a series of heat recovery processes, it is then cooled and dust-removed by a quenching component to obtain clean material gas. This clean material gas then enters the coarse fractionation tower 21 through a reboiler for heat exchange and cooling. The cooled material liquid enters the loading tank 23, and the temperature of the cooled material is around 120 degrees Celsius. The cooled material enters the tube side of the first heat exchanger 32 to exchange heat with the cold material transported by the distillation equipment. The temperature of the cold material rises to 80 degrees Celsius, and the temperature of the material drops to 90 degrees Celsius. The cold material enters the coarse fractionation tower 21 through the distillation pipe 31. After further cooling by the first cooler 33, the material returns to the distillation equipment for distillation. This not only saves the amount of steam used to heat the coarse fractionation tower 21 but also extends the service life of the first cooler 33, thereby achieving the technical effect of reducing enterprise production costs.
[0022] The fluidization component described above includes a fluidized bed 11 and a quenching component. The fluidized bed 11 is connected to the quenching component. The tail gas generated by the reaction in the fluidized bed 11, after heat exchange, enters the quenching component for cooling and dust removal, resulting in clean material. The coarse separation component includes a coarse separation tower 21, a reboiler, and a loading tank 23. The middle part of the reboiler is connected to the quenching component, the upper end of the reboiler is connected to the coarse separation tower 21, and the loading tank 23 is connected to the lower part of the reboiler. The material undergoes heat exchange and cooling treatment through the reboiler, and the cooled gas condenses into liquid and enters the loading tank 23. The function of the heat exchange component is to perform heat exchange treatment on the product. The heat exchange component includes a distillation pipe 31, a first heat exchanger 32, and a first cooler 33. One end of the distillation pipe 31 is connected to... One end of the shell side of the first heat exchanger 32 is connected to the shell side, and the other end is connected to the coarse fractionation column 21. One end of the tube side of the first heat exchanger 32 is connected to the loading tank 23, and the other end is connected to the first cooler 33. The material temperature in the loading tank 23 is about 120 degrees Celsius. After cooling, the material enters the tube side of the first heat exchanger 32 to exchange heat with the cold material transported by the distillation equipment. The temperature of the cold material rises to 80 degrees Celsius, and the temperature of the material drops to 90 degrees Celsius. The cold material enters the coarse fractionation column 21 through the distillation pipe 31. After being further cooled by the first cooler 33, the material returns to the distillation equipment for distillation. This not only saves the amount of steam used to heat the coarse fractionation column 21, but also extends the service life of the first cooler 33, thereby achieving the technical effect of reducing the enterprise's production costs.
[0023] Furthermore, the reboiler includes a first reboiler 221 and a second reboiler 222. The quenching component is connected to the side of the first reboiler 221. A first connecting pipe 223 is provided at the upper end of the first reboiler 221 and the second reboiler 222. A second connecting pipe 224 is provided at the lower end of the first reboiler 221 and the second reboiler 222. The coarse separation tower 21 is connected to the first connecting pipe 223 and the second connecting pipe 224 respectively. A third connecting pipe 225 is provided between the first reboiler 221 and the loading tank 23. In this embodiment, the reboilers are further defined. The first reboiler 221 is a material reboiler, and the second reboiler 222 is a steam reboiler. After the material discharged from the quenching component enters the first reboiler 221, it is heated by the first reboiler 221 and then enters the coarse separation column 21 for heat exchange and cooling. Then, it enters the loading tank 23 through the third connecting pipe 225. The second reboiler 222 heats the liquid at the bottom of the column, causing it to partially vaporize and form rising steam, thereby realizing mass and heat transfer between the gas and liquid phases. Furthermore, the steam generated by the steam reboiler forms countercurrent contact with the reflux liquid at the top of the column to ensure separation efficiency.
[0024] Furthermore, the quenching component includes a second heat exchanger 12 and a quenching tower 13. The upper end of the second heat exchanger 12 is connected to the fluidized bed 11, and the lower end of the second heat exchanger 12 is connected to the quenching tower 13. In this embodiment, the quenching component is further defined. The material temperature discharged from the fluidized bed 11 is around 530 degrees Celsius. After heat exchange in the second heat exchanger 12, the material discharged from the fluidized bed 11 enters the quenching tower 13 for cooling and then enters the first reboiler 221, thereby achieving the technical effect of reducing the material temperature.
[0025] Furthermore, a distillation spherical tank 4 is added, which is connected to the other end of the shell side of the first heat exchanger 32. In this embodiment, the distillation spherical tank 4 is added, and the temperature of the cold feed output from the distillation spherical tank 4 is about 60 degrees Celsius. The cold feed output from the distillation spherical tank 4 exchanges heat with the material discharged from the loading tank 23 in the first heat exchanger 32, thereby achieving the technical effect of reducing the temperature of the material.
[0026] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the protection scope of the claims.
Claims
1. A heat recovery system for cold hydrogenation products, characterized in that, include: A fluidizing component, comprising a fluidized bed and a quenching component, wherein the fluidized bed is connected to the quenching component; The coarse separation component includes a coarse separation tower, a reboiler, and a loading tank. The middle part of the reboiler is connected to the quenching component, the upper end of the reboiler is connected to the coarse separation tower, and the loading tank is connected to the lower part of the reboiler. The heat exchange component includes a distillation pipe, a first heat exchanger, and a first cooler. One end of the distillation pipe is connected to one end of the shell side of the first heat exchanger, and the other end is connected to the crude fractionation column. One end of the tube side of the first heat exchanger is connected to the loading tank, and the other end is connected to the first cooler.
2. The cold hydrogenation product heat recovery system according to claim 1, characterized in that, The reboiler includes a first reboiler and a second reboiler. The quenching component is connected to the side of the first reboiler. A first connecting pipe is provided at the upper end of the first reboiler and the second reboiler. A second connecting pipe is provided at the lower end of the first reboiler and the second reboiler. The coarse separator is connected to the first connecting pipe and the second connecting pipe respectively. A third connecting pipe is provided between the first reboiler and the loading tank.
3. The cold hydrogenation product heat recovery system according to claim 2, characterized in that, The quenching component includes a second heat exchanger and a quenching tower. The upper end of the second heat exchanger is connected to the fluidized bed, and the lower end of the second heat exchanger is connected to the quenching tower.
4. The cold hydrogenation product heat recovery system according to claim 3, characterized in that, Also includes: A distillation spherical tank is connected to the other end of the shell side of the first heat exchanger.