Chilled water preparation system for polycrystalline silicon production line and polycrystalline silicon production line
By using air-cooled heat exchangers and liquid nitrogen vaporizers in the polycrystalline silicon production line to initially cool the refrigeration water, and then further cool down with lithium bromide refrigeration equipment, the problem of large energy consumption of lithium bromide refrigeration machines is solved and the energy efficiency of the refrigerated water preparation system is improved.
Patent Information
- Application Number
- CN202420906631.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Priority Date
- 2024-04-10
- Filing Date
- 2024-04-28
- Publication Date
- 2024-12-27
- Estimated Expiration
- 2034-04-28
AI Technical Summary
The lithium bromide refrigerator in the existing polysilicon production lines consumes a lot of energy, resulting in low energy efficiency of the refrigerated water preparation system.
The refrigerated water is initially cooled by air-cooled heat exchanger and liquid nitrogen vaporizer, and then the refrigeration equipment is further cooled by using lithium bromide refrigeration equipment to form a refrigerated water recycling system to reduce the energy consumption of lithium bromide refrigeration equipment.
Through the combined use of air-cooled heat exchanger and liquid nitrogen vaporizer, the energy consumption of lithium bromide refrigeration equipment is reduced, the energy efficiency of the refrigerated water preparation system is improved, and the temperature of the refrigerated water is effectively reduced.
Smart Images
Figure CN222257199U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of polysilicon production, and in particular to a chilled water preparation system for a polysilicon production line and a polysilicon production line. Background Art
[0002] The modified Siemens method is the mainstream technology for producing polysilicon in the world. In the process of producing polysilicon, a large amount of chilled water is used for cooling. The current process is to cool the 12°C chilled water return water through the lithium bromide refrigeration equipment to 7°C, and then transport the prepared 7°C chilled water to the demand side of the process system. After heat exchange at the demand side, the 7°C chilled water temperature rises to 12°C, and then the 12°C chilled water return water is transported to the lithium bromide refrigeration equipment for cooling treatment. The chilled water of the system can be recycled. The lithium bromide refrigerator contains refrigerant, which uses the waste heat of the 105°C heat source in the system to evaporate the refrigerant for heat absorption, thereby achieving the purpose of cooling. Although the lithium bromide refrigerator uses the waste heat of the system, its unit consumes a lot of energy.
[0003] Based on this, the present application provides a chilled water preparation system for a polysilicon production line and a polysilicon production line. Utility Model Content
[0004] The embodiments of the present application provide a chilled water preparation system for a polysilicon production line and a polysilicon production line, which can improve the problem of high energy consumption of lithium bromide refrigerators in the prior art.
[0005] The embodiment of the present application is implemented as follows:
[0006] In a first aspect, the present application provides a chilled water preparation system for a polysilicon production line, comprising:
[0007] An air-cooled heat exchanger, wherein the pipeline of the air-cooled heat exchanger is used to pass 12°C chilled water, and the air-cooled heat exchanger has an air inlet and is used to control the entry of outside air;
[0008] a liquid nitrogen vaporizer, wherein the chilled water inlet of the liquid nitrogen vaporizer is connected to the pipeline outlet of the air-cooled heat exchanger so as to cool the chilled water coming out of the air-cooled heat exchanger by liquid nitrogen; and
[0009] A lithium bromide refrigeration device, wherein the chilled water inlet of the lithium bromide refrigeration device is connected to the chilled water outlet of the liquid nitrogen vaporizer, so that the chilled water coming out of the liquid nitrogen vaporizer is cooled by the refrigerant in the lithium bromide refrigeration device.
[0010] In a possible implementation scheme, the air inlet of the air-cooled heat exchanger is provided with a first valve, the air-cooled heat exchanger is provided with a first controller electrically connected to the first valve and a first thermometer for detecting the outside air temperature, and the first thermometer is electrically connected to the first controller.
[0011] In a possible implementation manner, a fan is provided at the bottom of the air-cooled heat exchanger, and the fan is configured to draw external air into the air-cooled heat exchanger.
[0012] In a possible implementation, the air-cooled heat exchanger is a finned radiator.
[0013] In a possible implementation, the air-cooled heat exchanger includes a plurality of cooling sections and a standby cooling section that are connected to each other.
[0014] In a possible embodiment, the chilled water preparation system also includes a heat source supply device, which is connected to the lithium bromide refrigeration equipment to supply a 105°C heat source to the lithium bromide refrigeration equipment to react with the refrigerant, so that the refrigerant evaporates and absorbs heat to cool the chilled water coming out of the liquid nitrogen vaporizer.
[0015] In a possible implementation scheme, the chilled water inlet of the lithium bromide refrigeration equipment is connected to the chilled water outlet of the liquid nitrogen vaporizer through a first pipe, a second thermometer is provided on the first pipe, the chilled water preparation system is also provided with a second controller, the second controller is electrically connected to the second thermometer, and the heat source supply device is electrically connected to the second controller.
[0016] In a possible implementation, the liquid nitrogen inlet of the liquid nitrogen vaporizer is connected to a liquid nitrogen storage tank, and the liquid nitrogen storage tank is used to supply liquid nitrogen to the liquid nitrogen vaporizer.
[0017] In a possible implementation manner, the liquid nitrogen inlet of the liquid nitrogen vaporizer is connected to the liquid nitrogen storage tank through a second pipeline, and the second pipeline is provided with a second valve.
[0018] In a second aspect, the present application provides a polysilicon production line, which includes the chilled water preparation system of the first aspect.
[0019] The embodiments of the present application have at least the following beneficial effects:
[0020] The chilled water preparation system for a polysilicon production line of the present application can cool down the 12°C chilled water by exchanging heat between the outside cold air and the 12°C chilled water through an air-cooled heat exchanger, further cool down the chilled water using the liquid nitrogen in the liquid nitrogen vaporizer, and further cool down the chilled water through a lithium bromide refrigeration device, so that the chilled water coming out of the lithium bromide refrigeration device can reach 7°C. Since the chilled water preparation system of the present application first cools down the chilled water through a liquid nitrogen vaporizer and an air-cooled heat exchanger before using the lithium bromide refrigeration device to cool down the chilled water, the energy consumption of the lithium bromide refrigeration device can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.
[0022] Figure 1 This is a chilled water preparation system according to an embodiment of the present application.
[0023] Icons: 10-chilled water preparation system; 11-air-cooled heat exchanger; 12-liquid nitrogen vaporizer; 13-lithium bromide refrigeration equipment; 14-first thermometer; 16-second thermometer; 17-liquid nitrogen storage tank; 18-second valve. DETAILED DESCRIPTION
[0024] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.
[0025] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.
[0026] In the description of the present application, it should be noted that the terms "first", "second", "third", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.
[0027] In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "disposed" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances. Example
[0028] This embodiment provides a chilled water preparation system 10 for a polysilicon production line. Figure 1 , which includes an air-cooled heat exchanger 11, a liquid nitrogen vaporizer 12 and a lithium bromide refrigeration device 13.
[0029] The pipeline of the air-cooled heat exchanger 11 is used to pass 12°C chilled water, and the air-cooled heat exchanger 11 has an air inlet and is used to control the entry of outside air. Exemplarily, the air inlet of the air-cooled heat exchanger 11 is provided with a first valve, the air-cooled heat exchanger 11 is provided with a first controller electrically connected to the first valve and a first thermometer 14 for detecting the temperature of the outside air, and the first thermometer 14 is electrically connected to the first controller.
[0030] When the first thermometer 14 detects that the outside air temperature is less than 12°C, the first controller controls the first valve to open, and the outside cold air can enter the air-cooled heat exchanger 11 from the air inlet of the air-cooled heat exchanger 11, perform heat exchange with the 12°C chilled water in the pipeline of the air-cooled heat exchanger 11, and cool the 12°C chilled water. When the first thermometer 14 detects that the outside air temperature is greater than or equal to 12°C, the first controller controls the first valve to close the air inlet, and the hotter outside air cannot enter the air-cooled heat exchanger 11.
[0031] The chilled water inlet of the liquid nitrogen vaporizer 12 is connected to the pipeline outlet of the air-cooled heat exchanger 11, so that the chilled water coming out of the air-cooled heat exchanger 11 is cooled by liquid nitrogen. The chilled water inlet of the lithium bromide refrigeration equipment 13 is connected to the chilled water outlet of the liquid nitrogen vaporizer 12, so that the chilled water coming out of the liquid nitrogen vaporizer 12 is cooled by the refrigerant in the lithium bromide refrigeration equipment 13.
[0032] Among them, the liquid nitrogen inlet of the liquid nitrogen vaporizer 12 is connected to a liquid nitrogen storage tank 17, and the liquid nitrogen storage tank 17 is used to supply liquid nitrogen to the liquid nitrogen vaporizer 12. The liquid nitrogen storage tank 17 can reserve a sufficient amount of liquid nitrogen in advance for easy use in the process. Exemplarily, the liquid nitrogen inlet of the liquid nitrogen vaporizer 12 is connected to the liquid nitrogen storage tank 17 through a second pipeline, and the second pipeline is provided with a second valve 18. The second valve 18 can be conveniently controlled to supply the liquid nitrogen in the liquid nitrogen storage tank 17 to the liquid nitrogen vaporizer 12. Optionally, the second valve 18 is a flow valve, which can control the flow rate of liquid nitrogen supplied to the liquid nitrogen vaporizer 12.
[0033] The chilled water preparation system 10 for a polysilicon production line of the present application can cool the 12°C chilled water by heat exchange between the outside cold air and the 12°C chilled water through the air-cooled heat exchanger 11 when the outside air temperature is less than 12°C, and further cool the chilled water by using the liquid nitrogen in the liquid nitrogen vaporizer 12. When the outside air temperature is greater than or equal to 12°C, the 12°C chilled water enters the liquid nitrogen vaporizer 12 from the pipeline of the air-cooled heat exchanger 11, and the chilled water is cooled by the liquid nitrogen in the liquid nitrogen vaporizer 12.
[0034] Afterwards, the cooled chilled water is further cooled by the lithium bromide refrigeration equipment 13, so that the chilled water coming out of the lithium bromide refrigeration equipment 13 can reach 7° C. Since the chilled water preparation system 10 of the present application first cools the chilled water by passing through the liquid nitrogen vaporizer 12 and the air-cooled heat exchanger 11 before using the lithium bromide refrigeration equipment 13 to cool the chilled water, the energy consumption of the lithium bromide refrigeration equipment 13 can be reduced.
[0035] Since the specific heat of air is relatively low, in order to further increase the heat exchange effect, a fan is provided at the bottom of the air-cooled heat exchanger 11, and the fan is configured to draw outside air into the air-cooled heat exchanger 11. The fan increases the air volume and wind speed entering the air-cooled heat exchanger 11, thereby increasing the heat exchange effect and improving the heat exchange efficiency. Exemplarily, the air-cooled heat exchanger 11 is a finned radiator, and the air-cooled heat exchanger 11 includes multiple cooling sections and spare cooling sections that are connected, so that the heat exchange effect is better.
[0036] Among them, the chilled water preparation system 10 also includes a heat source supply device, which is connected to the lithium bromide refrigeration equipment 13 to supply a 105°C heat source to the lithium bromide refrigeration equipment 13 to react with the refrigerant, so that the refrigerant evaporates and absorbs heat to cool the chilled water coming out of the liquid nitrogen vaporizer 12.
[0037] Optionally, the chilled water inlet of the lithium bromide refrigeration equipment 13 is connected to the chilled water outlet of the liquid nitrogen vaporizer 12 through a first pipe, a second thermometer 16 is provided on the first pipe, and the chilled water preparation system 10 is also provided with a second controller, the second controller is electrically connected to the second thermometer 16, and the heat source supply device is electrically connected to the second controller.
[0038] The second thermometer 16 can detect the temperature of the chilled water coming out of the liquid nitrogen vaporizer 12 and transmit the temperature to the controller. The controller controls the heat source supply device to supply a 105°C heat source to the lithium bromide refrigeration device 13 to achieve linkage control. The 105°C heat source reacts with the refrigerant, causing the refrigerant to evaporate and absorb heat to cool the chilled water coming out of the liquid nitrogen vaporizer 12.
[0039] This embodiment also provides a polysilicon production line, which includes the chilled water preparation system 10 of the first aspect.
[0040] Among them, the heat source supply equipment is a part of the polysilicon production line, which is not only used in other processes, but also used in the chilled water preparation system 10, thereby improving the waste heat utilization rate of the entire system.
[0041] In summary, the chilled water preparation system 10 for a polysilicon production line of the present application can cool down the 12°C chilled water by heat exchange between the outside cold air and the 12°C chilled water through the air-cooled heat exchanger 11, further cool down the chilled water using the liquid nitrogen in the liquid nitrogen vaporizer 12, and further cool down the chilled water through the lithium bromide refrigeration equipment 13, so that the chilled water coming out of the lithium bromide refrigeration equipment 13 can reach 7°C. Because the chilled water is first cooled by the liquid nitrogen vaporizer 12 and the air-cooled heat exchanger 11 before being cooled by the lithium bromide refrigeration equipment 13, the operating cost of the large amount of heat source and cold source consumption of the lithium bromide refrigeration equipment 13 can be reduced, and energy consumption can be reduced.
[0042] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims
1. A chilled water preparation system for a polysilicon production line, characterized in that: include: An air-cooled heat exchanger, wherein the pipeline of the air-cooled heat exchanger is used to pass 12°C chilled water, and the air-cooled heat exchanger has an air inlet and is used to control the entry of outside air; A liquid nitrogen vaporizer, wherein the chilled water inlet of the liquid nitrogen vaporizer is connected to the pipeline outlet of the air-cooled heat exchanger, so as to cool the chilled water coming out of the air-cooled heat exchanger by liquid nitrogen; as well as A lithium bromide refrigeration device, wherein the chilled water inlet of the lithium bromide refrigeration device is connected to the chilled water outlet of the liquid nitrogen vaporizer, so that the chilled water coming out of the liquid nitrogen vaporizer is cooled by the refrigerant in the lithium bromide refrigeration device.
2. The chilled water preparation system for a polysilicon production line according to claim 1, characterized in that: The air inlet of the air-cooling heat exchanger is provided with a first valve, the air-cooling heat exchanger is provided with a first controller electrically connected to the first valve and a first thermometer for detecting the temperature of the outside air, and the first thermometer is electrically connected to the first controller.
3. The chilled water preparation system for a polysilicon production line according to claim 1, characterized in that: A fan is provided at the bottom of the air-cooled heat exchanger, and the fan is configured to draw outside air into the air-cooled heat exchanger.
4. The chilled water preparation system for a polysilicon production line according to claim 1, characterized in that: The air-cooled heat exchanger is a finned radiator.
5. The chilled water preparation system for a polysilicon production line according to claim 4, characterized in that: The air-cooling heat exchanger comprises a plurality of cooling sections and a standby cooling section which are connected to each other.
6. The chilled water preparation system for a polysilicon production line according to any one of claims 1 to 5, characterized in that: The chilled water preparation system also includes a heat source supply device, which is connected to the lithium bromide refrigeration device to supply a 105°C heat source to the lithium bromide refrigeration device to react with a refrigerant, so that the refrigerant evaporates and absorbs heat to cool the chilled water coming out of the liquid nitrogen vaporizer.
7. The chilled water preparation system for a polysilicon production line according to claim 6, characterized in that: The chilled water inlet of the lithium bromide refrigeration equipment is connected to the chilled water outlet of the liquid nitrogen vaporizer through a first pipe, a second thermometer is provided on the first pipe, the chilled water preparation system is also provided with a second controller, the second controller is electrically connected to the second thermometer, and the heat source supply device is electrically connected to the second controller.
8. The chilled water preparation system for a polysilicon production line according to any one of claims 1 to 5, characterized in that: The liquid nitrogen inlet of the liquid nitrogen vaporizer is connected to a liquid nitrogen storage tank, and the liquid nitrogen storage tank is used to supply liquid nitrogen to the liquid nitrogen vaporizer.
9. The chilled water preparation system for a polysilicon production line according to claim 8, characterized in that: The liquid nitrogen inlet of the liquid nitrogen vaporizer is connected to the liquid nitrogen storage tank through a second pipeline, and the second pipeline is provided with a second valve.
10. A polysilicon production line, characterized in that: It comprises the chilled water preparation system according to any one of claims 1 to 9.