Water removal device for fluorine-containing electronic special gas purification process

Abstract

The utility model belongs to chemical industry water trap technical field, concretely relates to be used for fluorine-containing electronic special gas purification process water trap. The utility model discloses a water trap for fluorine-containing electronic special gas purification process, water trap includes water trap structure and low pressure adsorption structure, and water trap structure includes water trap A, water trap B, water trap C, water trap D, water trap E, water trap F, and low pressure adsorption structure includes diaphragm compressor A, diaphragm compressor B, diaphragm compressor C, diaphragm compressor A is connected with diaphragm compressor B, diaphragm compressor B is connected with diaphragm compressor C, and diaphragm compressor C is connected with water trap A. The utility model provides a water trap for fluorine-containing electronic special gas purification process, through the way that multistage water trap and low pressure adsorption are combined, has realized the efficient, depth removal of water content in fluorine-containing electronic special gas gas, and system integration degree is high, and stable and reliable operation.

Description

Technical Field

[0001] This utility model belongs to the technical field of chemical dewatering devices, specifically relating to a dewatering device for purifying fluorine-containing electronic special gases. Background Technology

[0002] Fluorine-containing electronic specialty gases, including SF6 and NF3, are ideal insulating media and etchants. They are widely used in gas-insulated switchgear (GIS), circuit breakers, load switchgear, insulated transmission lines in the power industry, as well as in plasma etching processes in the field of microelectronics.

[0003] Currently, the purification process for fluorinated electronic specialty gases typically includes steps such as water washing, alkali washing, compression, adsorption, and distillation. Crude fluorinated electronic specialty gases usually contain various impurities, including moisture, low-fluoride compounds, N2, O2, CF4, CO2, and C2F6. The standard purification process first removes soluble impurities and acidic components through water and alkali washing, then pressurizes the gas, followed by deep drying and purification in a low-pressure adsorption tower (usually filled with silica gel and alumina gel), and finally enters a gas holder for buffering or subsequent distillation.

[0004] However, in existing processes, when the process material is washed with alkali and then enters the low-pressure adsorption tower through a compressor, it carries a large amount of moisture. This is mainly because the moisture carryover problem is severe, and the compression process cannot effectively separate saturated water vapor in the gas phase, resulting in a large amount of moisture entering the adsorption tower. This leads to a shortened adsorbent lifespan; adsorbent materials such as silica gel and alumina gel have limited moisture adsorption capacity, and high humidity loads cause them to quickly saturate and deactivate, typically requiring replacement every 3-4 months. Operating costs are high; frequent replacement of packing materials not only increases the consumption of materials such as silica gel and alumina gel but also incurs high labor maintenance costs and downtime losses. There is also a risk to product purity; adsorbent performance degradation may lead to incomplete moisture removal, affecting the purity of the final product. Electronic-grade fluorinated electronic specialty gases require a purity higher than 99.999%, and the moisture content must be controlled at extremely low levels (e.g., <20ppm). Residual moisture may also form corrosive acids with other impurities, damaging equipment and endangering operational safety.

[0005] Existing technologies employ multi-stage (e.g., three-stage) adsorption tower series processes (such as a combination of silica gel tower and alumina tower), combined with fluorine adsorbents and 13X molecular sieves, to extend the adsorbent's lifespan. However, this method does not fundamentally solve the problem of excessive pre-treatment moisture load, and its effectiveness is limited. Patent CN111186819A proposes a low-temperature cooling dehydration approach. Low-temperature cooling utilizes the principle that the partial pressure of water vapor in sulfur hexafluoride decreases with decreasing temperature, achieving water-gas separation through condensation. Existing devices use refrigeration units to cool the gas to 0-5°C or even lower, causing the moisture to condense, liquefy, and then separate and discharge. For example, the device involved in CN114111220A employs a water seal design and multi-stage separation (such as a combination of water-gas separator, cyclone separator, and refrigerated dryer) to attempt automated drainage and reduce manual intervention. However, existing dehydration devices still have shortcomings in terms of efficiency, automation level, and integration with the overall process. For example, simple low-temperature cooling may still require deep drying in subsequent adsorption stages; some devices have low condensation efficiency; or they have not fully considered efficient coupling with existing water washing, alkali washing, compression, and adsorption processes. Utility Model Content

[0006] The technical problem to be solved by this utility model is to overcome the above-mentioned defects in the existing technology and provide a water removal device for the purification process of fluorine-containing electronic special gases. By combining multi-stage water removal with low-pressure adsorption, it achieves efficient and deep removal of moisture from fluorine-containing electronic special gases. The system has high integration and stable and reliable operation.

[0007] The present invention relates to a dehydration device for purifying fluorine-containing electronic special gases. The dehydration device includes a dehydration structure and a low-pressure adsorption structure. The dehydration structure includes dehydrator A, dehydrator B, dehydrator C, dehydrator D, dehydrator E, and dehydrator F. The low-pressure adsorption structure includes diaphragm compressor A, diaphragm compressor B, and diaphragm compressor C. Diaphragm compressor A is connected to diaphragm compressor B, diaphragm compressor B is connected to diaphragm compressor C, and diaphragm compressor C is connected to dehydrator A. The water separator A is connected to water separator B, water separator B is connected to water separator C, water separator C is connected to water separator D, water separator D is connected to water separator E, water separator E is connected to water separator F, water separator F is connected to a buffer tank, the buffer tank is connected to the low-pressure adsorption tower of group A, and the low-pressure adsorption tower of group A is connected to a fluorine-containing electronic special gas collection pipe.

[0008] The low-pressure adsorption towers of Group A, Group B, Group C, and Group D are connected in parallel, and their gas outlets are all connected to a fluorine-containing electronic special gas collection pipe.

[0009] The water separators A, B, C, D, E, and F are all connected in parallel, as are the diaphragm compressors A, B, and C. The gas outlets of the diaphragm compressors A, B, and C are connected to the gas inlets of the water separators A, B, C, D, E, and F.

[0010] The water separators A, B, C, D, E, and F are all equipped with pipes that connect to the refrigerant return pipe and the refrigerant inlet pipe, respectively, and a refrigerant transfer tank is installed between the refrigerant return pipe and the refrigerant inlet pipe.

[0011] The water separators A, B, C, D, E, and F are all equipped with pipelines connected to the main nitrogen pipeline.

[0012] The refrigerant transfer tank is connected to the nitrogen main pipe.

[0013] The water separators A, B, C, D, E, and F are equipped with pipes that connect to the fluorine-containing electronic special gas recovery pipe.

[0014] The diaphragm compressors A, B, and C are all equipped with circulating water supply pipes and circulating water return pipes.

[0015] The diaphragm compressors A, B, and C are all equipped with pipelines that connect to the inlet pipe for fluorinated electronic special gas.

[0016] Compared with the prior art, the beneficial effects of this utility model are: This invention employs a six-stage series dehydrator combined with multiple parallel adsorption towers to form a "freezing + adsorption" composite dehydration process, which can completely remove moisture from SF6 gas. The system adopts a parallel switchable design, enabling continuous operation and online regeneration. Material and cooling energy are recovered through SF6 recovery pipes and a refrigerant circulation system, resulting in energy conservation and environmental protection. A diaphragm compressor ensures sealing, while a nitrogen purging and cooling system ensures safe and reliable operation. The parallel design of multiple compressors and adsorption towers allows for flexible adjustment of processing capacity. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the process flow of the water removal device for the purification process of fluorine-containing electronic special gases according to this utility model.

[0018] Figure 2 This is a schematic diagram showing the specific connections of the water removal structure and the low-pressure adsorption structure.

[0019] In the diagram: 1. Dehydrator A; 2. Dehydrator B; 3. Dehydrator C; 4. Dehydrator D; 5. Dehydrator E; 6. Dehydrator F; 7. Refrigerant transfer tank; 8. Buffer tank; 9. Diaphragm compressor A; 10. Diaphragm compressor B; 11. Diaphragm compressor C; 12. Group A low-pressure adsorption tower; 13. Group B low-pressure adsorption tower; 14. Group C low-pressure adsorption tower; 15. Group D low-pressure adsorption tower; 16. Fluorine-containing electronic special gas collection pipe; 17. Nitrogen main pipe; 18. Fluorine-containing electronic special gas recovery pipe; 19. Refrigerant return pipe; 20. Refrigerant inlet pipe; 21. Circulating water return pipe; 22. Fluorine-containing electronic special gas inlet pipe; 23. Circulating water supply pipe. Detailed Implementation

[0020] The present invention will be further described below with reference to specific embodiments.

[0021] The AF dehydrators are all existing conventional condensing dehydrators, available on the market, with no specific model number. The diaphragm compressor model is GL3110 / 4, brand is Zhongding Hengsheng.

[0022] The low-pressure adsorption tower has the following parameters (Table 1), and the manufacturer is Zibo Chemical Machinery Plant Co., Ltd.

[0023] Table 1 Structure of Low-Pressure Adsorption Tower

[0024] The fluorine-containing electronic specialty gas of this invention (taking SF6 as an example) is as follows: Figure 1 The processing flow shown is as follows: Figure 2 The water removal device shown is as follows: Figure 2 As shown, the sulfur fluoride purification process dewatering device includes a dewatering structure and a low-pressure adsorption structure. The dewatering structure includes dewatering units A1, B2, C3, D4, E5, and F6; the low-pressure adsorption structure includes diaphragm compressors A9, B10, and C11. Diaphragm compressor A9 is connected to diaphragm compressor B10, diaphragm compressor B10 is connected to diaphragm compressor C11, and diaphragm compressor C11 is connected to dewatering unit A1. The water separator A1 is connected to water separator B2, water separator B2 is connected to water separator C3, water separator C3 is connected to water separator D4, water separator D4 is connected to water separator E5, water separator E5 is connected to water separator F6, water separator F6 is connected to buffer tank 8, buffer tank 8 is connected to low-pressure adsorption tower 12 of group A, and low-pressure adsorption tower 12 of group A is connected to fluorine-containing electronic special gas collection pipe 16.

[0025] The low-pressure adsorption tower 12 of group A is connected in parallel with low-pressure adsorption tower 13 of group B, low-pressure adsorption tower 14 of group C and low-pressure adsorption tower 15 of group D, and their gas outlets are all connected to the fluorine-containing electronic special gas collection pipe 16.

[0026] The water separators A1, B2, C3, D4, E5, and F6 are all connected in parallel, as are the diaphragm compressors A9, B10, and C11. The gas outlets of the diaphragm compressors A9, B10, and C11 are connected to the gas inlets of the water separators A1, B2, C3, D4, E5, and F6.

[0027] The water separators A1, B2, C3, D4, E5, and F6 are all equipped with pipes that connect to the refrigerant return pipe 19 and the refrigerant inlet pipe 20, respectively. A refrigerant transfer tank 7 is installed between the refrigerant return pipe 19 and the refrigerant inlet pipe 20.

[0028] The water separators A1, B2, C3, D4, E5, and F6 are all equipped with pipes connected to the nitrogen main pipe 17.

[0029] The refrigerant transfer tank 7 is connected to the nitrogen main pipe 17.

[0030] The water separators A1, B2, C3, D4, E5, and F6 are equipped with pipes that connect to the fluorine-containing electronic special gas recovery pipe 18.

[0031] The diaphragm compressors A9, B10, and C11 are all equipped with a circulating water supply pipe 23 and a circulating water return pipe 21.

[0032] The diaphragm compressors A9, B10, and C11 are all equipped with pipelines that are connected to the fluorine-containing electronic special gas inlet pipe 22.

[0033] When the above device is in operation, the fluorinated electronic special gas raw material gas containing moisture to be purified enters the system through the fluorinated electronic special gas inlet pipe 22. After being pressurized by the parallel diaphragm compressors A9, B10 and C11, it is delivered to the parallel water separators A1 to F6.

[0034] In the dehydrator, low-temperature refrigerant from the refrigerant inlet pipe 20 and distributed via the refrigerant transfer tank 7 is introduced to freeze and cool the SF6 gas, causing the moisture in it to condense and precipitate. Six dehydrators are connected in series, and the gas passes through them sequentially for multi-stage freezing and dehydration, significantly improving the dehydration efficiency. The used refrigerant is returned to the refrigeration system through the refrigerant return pipe 19.

[0035] After deep freezing and dehydration, the gas flows out from the dehydrator F6 and enters the buffer tank 8 for buffering and pressure stabilization before entering the low-pressure adsorption structure. The adsorption structure consists of four sets of parallel low-pressure adsorption towers. The gas passes through the adsorption towers containing highly efficient desiccants (such as molecular sieves) for final dehydration, ensuring that the moisture content of the outlet gas meets extremely high purity requirements. The purified and qualified SF6 gas is discharged through the fluorine-containing electronic special gas collection pipe 16.

[0036] When a desiccant or adsorption tower requires regeneration, its inlet and outlet valves are closed, disconnecting it from the production process. Nitrogen is introduced through the nitrogen main pipe 17 to purge and regenerate the equipment, and the desorbed moisture is discharged with the nitrogen. A small amount of SF6 gas carried out during the purging process is collected through the fluorine-containing electronic special gas recovery pipe 18 and returned to the raw material end to avoid waste. During this process, other parallel equipment continues to operate, ensuring that the entire purification process is uninterrupted.

[0037] The heat generated by the diaphragm compressor during operation is supplied to cooling water through the circulating water supply pipe 23 and discharged through the circulating water return pipe 21 to maintain the compressor operating at a normal temperature.

[0038] Of course, the above description is only a preferred embodiment of this utility model and should not be considered as limiting the scope of the embodiments of this utility model. This utility model is not limited to the above examples, and all equivalent changes and improvements made by those skilled in the art within the scope of this utility model should be included in the patent coverage of this utility model.

Claims

1. A water removal device for purifying fluorine-containing electronic special gases, characterized in that: The dewatering device includes a dewatering structure and a low-pressure adsorption structure. The dewatering structure includes dewatering device A (1), dewatering device B (2), dewatering device C (3), dewatering device D (4), dewatering device E (5), and dewatering device F (6). The low-pressure adsorption structure includes diaphragm compressor A (9), diaphragm compressor B (10), and diaphragm compressor C (11). The diaphragm compressor A (9) is connected to the diaphragm compressor B (10), the diaphragm compressor B (10) is connected to the diaphragm compressor C (11), and the diaphragm compressor C (11) is connected to the dewatering device A (1). The water separator A (1) is connected to water separator B (2), water separator B (2) is connected to water separator C (3), water separator C (3) is connected to water separator D (4), water separator D (4) is connected to water separator E (5), water separator E (5) is connected to water separator F (6), water separator F (6) is connected to buffer tank (8), buffer tank (8) is connected to low-pressure adsorption tower (12) of group A, and low-pressure adsorption tower (12) of group A is connected to fluorine-containing electronic special gas collection pipe (16).

2. The dehydration device for purifying fluorine-containing electronic special gases according to claim 1, characterized in that: The A-group low-pressure adsorption tower (12) is connected in parallel with the B-group low-pressure adsorption tower (13), the C-group low-pressure adsorption tower (14), and the D-group low-pressure adsorption tower (15), and their gas outlets are all connected to the fluorine-containing electronic special gas collection pipe (16).

3. The dehydration device for purifying fluorine-containing electronic special gases according to claim 1, characterized in that: The water separators A (1), B (2), C (3), D (4), E (5), and F (6) are all connected in parallel. The diaphragm compressors A (9), B (10), and C (11) are also connected in parallel. The gas outlets of the diaphragm compressors A (9), B (10), and C (11) are connected to the gas inlets of the water separators A (1), B (2), C (3), D (4), E (5), and F (6).

4. The dehydration device for purifying fluorine-containing electronic special gases according to claim 1, characterized in that: The water separators A (1), B (2), C (3), D (4), E (5), and F (6) are all equipped with pipes that are connected to the refrigerant return pipe (19) and the refrigerant inlet pipe (20) respectively. A refrigerant transfer tank (7) is provided between the refrigerant return pipe (19) and the refrigerant inlet pipe (20).

5. The dehydration device for purifying fluorine-containing electronic special gases according to claim 4, characterized in that: The water separators A (1), B (2), C (3), D (4), E (5), and F (6) are all equipped with pipes connected to the nitrogen main pipe (17).

6. The dehydration device for purifying fluorine-containing electronic special gases according to claim 5, characterized in that: The refrigerant transfer tank (7) is connected to the nitrogen main pipe (17).

7. The dehydration device for purifying fluorine-containing electronic special gases according to claim 1, characterized in that: The water separators A (1), B (2), C (3), D (4), E (5), and F (6) are equipped with pipes that are connected to the fluorine-containing electronic special gas recovery pipe (18).

8. The dehydration device for purifying fluorine-containing electronic special gases according to claim 1, characterized in that: The diaphragm compressors A (9), B (10), and C (11) are all equipped with a circulating water supply pipe (23) and a circulating water return pipe (21).

9. The dehydration device for purifying fluorine-containing electronic special gases according to claim 1, characterized in that: The diaphragm compressors A (9), B (10), and C (11) are all equipped with pipelines that are connected to the fluorine-containing electronic special gas inlet pipe (22).

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