Hydrogen purification method and system in a semiconductor package test system

Abstract

The application relates to the technical field of semiconductor MEMS processing, and discloses a hydrogen purification method and system in a semiconductor packaging test system, which comprises the following steps: in the adsorption stage, water-containing hydrogen is introduced from the bottom of a water removal adsorption tower, water in the hydrogen is preliminarily adsorbed by upper molecular sieves, and then the hydrogen is deeply adsorbed by lower molecular sieves, so that dry hydrogen is obtained and output from the top of the tower; when it is detected that the dew point of outlet hydrogen reaches a set breakthrough point, the adsorption is stopped, and the regeneration stage is entered; in the regeneration stage, dry regeneration gas is heated to 200-350 DEG C by a heater, and then introduced into the water removal adsorption tower from the top of the tower, so that the molecular sieves are heated and desorbed, and the moisture after desorption is discharged from the bottom of the tower; after the desorption is completed, the adsorption tower is cooled by switching in normal-temperature dry regeneration gas. The single-tower design is suitable for a hydrogen system of a non-continuous operation test device, a small space and a scene with low gas processing capacity, and the gas cost of equipment is reduced.

Description

Technical Field

[0001] This invention relates to the field of semiconductor MEMS processing, and in particular to a method and system for hydrogen purification in a semiconductor packaging and testing system. Background Technology

[0002] Hydrogen, as a clean energy source and an important industrial gas, is widely used in fuel cells, semiconductor manufacturing, laboratories, and scientific research. In the packaging of various atomic clocks, infrared sights, gyroscopes, accelerometers, and other sensor components, hydrogen serves as a testing atmosphere. If it contains water vapor, it significantly impacts the reliability and accuracy of the sensor packaging tests.

[0003] In fuel cell applications, if the moisture content of hydrogen exceeds the standard, the catalyst layer of the fuel cell electrode will fail, reducing the battery's output power and lifespan. In the vapor deposition process, trace amounts of moisture in hydrogen can react with the wafer surface material, forming impurities and defects that affect the chip's performance and yield. In laboratory hydride generation-atomic fluorescence spectrometry analysis, moisture can interfere with the hydride generation efficiency, leading to significant deviations in the detection results and failing to meet the requirements of precise analysis. In the production of hydrogen peroxide, moisture entrained in hydrogen can also affect the stable production of hydrogen peroxide.

[0004] The existing Chinese patent CN 118663042 A is specifically designed for a hydrogen drying system and its control method for medium-pressure PEM electrolyzers. The shortcomings of this patent are that it has as many as 10 working stages, many program control steps, and relatively complex programming. Moreover, the design is highly targeted and not suitable for other application scenarios with smaller footprints and lower budgets.

[0005] The existing Chinese patent CN 223170655 U discloses a hydrogen drying device with low pressure, low dew point and low pressure drop. The shortcomings of this patent are that it has many valves, the equipment is relatively large in size and the program is relatively complicated, making it more suitable for working conditions that require continuous operation.

[0006] The existing Chinese patent CN 223276084 U discloses a hydrogen dryer for a hydrogen production system. The shortcomings of this patent are that although the device is relatively simple, it uses activated carbon desiccant as the packing material. The packing material is replaced directly after use, which results in high operating costs in the long run. In addition, the removal depth of water in the hydrogen is low, and there is a risk of gas path contamination after multiple packing material replacements. It is not suitable for application scenarios with lower dew point requirements. Summary of the Invention

[0007] The main objective of this invention is to solve the technical problems of low efficiency, large size, and complex procedures in existing drying equipment. A method for hydrogen purification in a semiconductor packaging and testing system includes the following steps: A water removal adsorption tower is provided, which is divided into upper and lower layers. The upper layer is filled with 3A type spherical molecular sieves with a particle size of 2~3 mm, and the lower layer is filled with 3A type spherical molecular sieves with a particle size smaller than that of the upper layer. The two layers are separated by a honeycomb porous partition. During the adsorption stage, hydrogen gas containing moisture is introduced from the bottom of the dehydration adsorption tower. After the moisture is initially adsorbed by the upper molecular sieve, it is further deeply adsorbed by the lower molecular sieve to obtain dry hydrogen gas, which is then output from the top of the tower. When the outlet hydrogen dew point is detected to reach the set breakthrough point, adsorption stops and the regeneration stage begins. During the regeneration stage, the dry regeneration gas is heated to 200~350℃ by a heater and then introduced into the dewatering adsorption tower from the top of the tower to heat and desorb the molecular sieve. The desorbed moisture is discharged from the bottom of the tower. After desorption is completed, switch to room temperature dry regeneration gas to cool the adsorption tower until the temperature inside the tower drops below 40°C and the dew point of the outlet gas is ≤ –40°C. After cooling is complete, the pressure in the adsorption tower is increased to the adsorption working pressure to prepare for the next adsorption cycle.

[0008] A second aspect of the present invention provides a hydrogen purification system in a semiconductor packaging and testing system, the system comprising: a raw material gas inlet path, a regeneration gas inlet path, and a water removal adsorption tower; The raw material gas inlet path is provided with a raw material gas inlet, a first emergency shut-off valve, a first pressure reducing valve, a first mass flow meter, a first pressure gauge, a first filter, and a first programmable valve in sequence along the gas inlet direction. The outlet of the first programmable valve is connected to the bottom inlet of the water removal adsorption tower. The top outlet of the water removal adsorption tower is sequentially connected to a safety valve, a second programmable valve, a first terminal filter, and a product gas valve, ultimately leading to the product gas outlet. The regenerated gas inlet path is sequentially equipped with a regenerated gas inlet, a second emergency shut-off valve, a second pressure reducing valve, a second mass flow meter, a third pressure gauge, a second filter, a heater, and a third programmable valve along the inlet direction. The outlet of the third programmable valve is connected to the top inlet of the water removal adsorption tower. The bottom outlet of the water removal adsorption tower is also connected to an exhaust gas outlet path, which is sequentially equipped with an exhaust gas outlet valve, a second terminal filter, a cooler, a fourth pressure gauge, a check valve, a flame arrester, and a rain cap along the outlet direction.

[0009] The present invention has the following beneficial effects: This invention uses a type 3A molecular sieve as the adsorbent, whose pore size is specifically designed for adsorbing water molecules and exhibits almost no adsorption of hydrogen, ensuring a high hydrogen recovery rate. In particular, the double-layer gradient packing structure (large particle size in the upper layer and small particle size in the lower layer) forms a progressively denser adsorption bed from top to bottom. This structure effectively increases the contact area and contact time between water molecules and the adsorbent, achieving deep dehydration and stably reducing the hydrogen dew point to below -70°C. The 99.9999% extremely high purity hydrogen product meets the stringent requirements for protective gas sources in semiconductor packaging testing, fundamentally avoiding chip oxidation and packaging defects caused by moisture, and greatly improving the accuracy of test results and product yield.

[0010] Traditional uniform, fine-particle-size packed beds, while possessing strong adsorption capacity, can lead to excessive airflow resistance (pressure drop). This invention addresses this by employing a top layer of larger-particle-size (2-3 mm) molecular sieves to effectively disperse and reduce the initial resistance of the feed gas entering the adsorption tower; a bottom layer of smaller-particle-size molecular sieves enables highly efficient fine adsorption at low gas velocities. This gradient combination structure ensures extremely high dehydration efficiency while significantly reducing the overall system pressure drop of the adsorption tower, decreasing the load on the front-end compressor, thereby reducing system energy consumption and saving long-term operating costs.

[0011] The honeycomb-shaped porous partition between the two layers of packing in this invention plays a crucial role in buffering and redistribution. It uniformly disperses the incoming airflow, preventing high-speed gas from directly impacting the lower layer of fine-particle packing, thus significantly reducing pulverization of the molecular sieve due to friction and collision. Simultaneously, this structure effectively prevents localized "channeling" effects, ensuring uniform airflow across the entire bed cross-section, allowing for full utilization of all adsorbents, preventing premature localized penetration or saturation, thereby extending the service life of the molecular sieve, reducing replacement frequency and maintenance downtime, and guaranteeing the long-term stability and reliability of the system. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the hydrogen dehydration system provided in an embodiment of the present invention.

[0013] The attached figures are labeled as follows: 1. Raw material gas inlet; 2. First emergency shut-off valve; 3. First pressure reducing valve; 4. First mass flow meter; 5. First pressure gauge; 6. First filter; 7. First programmable valve; 8. Water removal adsorption tower; 9. Safety valve; 10. Second programmable valve; 11. First terminal filter; 12. Second pressure gauge; 13. Product gas valve; 14. Product gas outlet; 15. Regenerated gas inlet; 16. Second emergency shut-off valve; 17. Second pressure reducing valve; 18. Second mass flow meter; 19. Third pressure gauge; 20. Second filter; 21. Heater; 22. Third programmable valve; 23. Exhaust gas discharge valve; 24. Second terminal filter; 25. Cooler; 26. Fourth pressure gauge; 27. Check valve; 28. Flame arrester; 29. ​​Rain cap. Detailed Implementation

[0014] The terms "first," "second," "third," "fourth," etc., used in the specification, claims, and accompanying drawings of this invention, are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" or "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0015] Currently, the mature technologies for deep removal of water vapor from hydrogen mainly include adsorption and membrane separation. Existing hydrogen dehydration equipment is driven by the market, has a large gas processing capacity, large equipment size, and high equipment price. It does not match the needs of various applications of drying hydrogen with small space, small gas consumption, and low budget. In such scenarios, it is necessary to simplify the system design and reduce the gas consumption cost.

[0016] Traditional adsorption methods for treating hydrogen often require the simultaneous adsorption of multiple impurity gases, such as hydrocarbons and carbon monoxide, during the design phase. They fail to optimize the bed pore structure and gas flow path for the diffusion characteristics of water molecules in hydrogen, resulting in redundant adsorption bed design, increased equipment size, and unsuitability for space-constrained miniaturized applications. Membrane separation can save on regeneration systems, but existing commercial hydrogen dehydration membranes have high membrane module replacement costs, and their designs are primarily geared towards the separation and purification of mixed gases, making them unsuitable for applications with a single purpose of water removal and limited budgets.

[0017] In existing hydrogen dehydration solutions, in order to achieve continuous hydrogen supply, a dual-tower parallel alternating adsorption and regeneration mode is often adopted. Although this improves gas production efficiency and stability, it requires high-precision sensors and complex program control systems, resulting in high initial investment costs and increasing the size and maintenance difficulty of the equipment.

[0018] For ease of understanding, the specific process of the embodiments of the present invention is described below. The hydrogen purification method in the semiconductor packaging and testing system of the present invention includes the following steps: A water removal adsorption tower is provided, which is divided into upper and lower layers. The upper layer is filled with 3A type spherical molecular sieves with a particle size of 2~3 mm, and the lower layer is filled with 3A type spherical molecular sieves with a particle size smaller than that of the upper layer. The two layers are separated by a honeycomb porous partition. During the adsorption stage, hydrogen gas containing moisture is introduced from the bottom of the dehydration adsorption tower. After the moisture is initially adsorbed by the upper molecular sieve, it is further deeply adsorbed by the lower molecular sieve to obtain dry hydrogen gas, which is then output from the top of the tower. When the outlet hydrogen dew point is detected to reach the set breakthrough point, adsorption stops and the regeneration stage begins. During the regeneration stage, the dry regeneration gas is heated to 200~350℃ by a heater and then introduced into the dewatering adsorption tower from the top of the tower to heat and desorb the molecular sieve. The desorbed moisture is discharged from the bottom of the tower. After desorption is completed, switch to room temperature dry regeneration gas to cool the adsorption tower until the temperature inside the tower drops below 40°C and the dew point of the outlet gas is ≤ –40°C. After cooling is complete, the pressure in the adsorption tower is increased to the adsorption working pressure to prepare for the next adsorption cycle.

[0019] like Figure 1 The system of the present invention is divided into two routes, including: Route 1 includes: raw material gas inlet 1, first emergency shut-off valve 2, first pressure reducing valve 3, first mass flow meter 4, first pressure gauge 5, first filter 6, first programmable valve 7, water removal adsorption tower 8, safety valve 9, second programmable valve 10, first terminal filter 11, second pressure gauge 12, product gas valve 13, and product gas outlet 14. Water-rich vapors of the raw material hydrogen enter the dehydration unit through the raw material gas inlet 1, which is connected to the inlet of the first emergency shut-off valve 2. The first emergency shut-off valve 2 is used to quickly cut off the gas flow in special circumstances to prevent further escalation. The outlet of the first emergency shut-off valve 2 is connected to the inlet of the first pressure reducing valve 3. The first pressure reducing valve 3 reduces the pressure of the raw material gas to the working pressure of the hydrogen dehydration system. The outlet of the first pressure reducing valve 3 is connected to the inlet of the first mass flow meter 4, which adjusts the gas flow rate according to working requirements. The outlet of the first mass flow meter 4 is connected to the first pressure gauge 5, which is then connected to the inlet of the first filter 6, which performs preliminary filtration of particulate matter in the raw material hydrogen. The first filter 6 is connected to the inlet of the first programmable valve 7, and the outlet of the first programmable valve 7 is connected to the inlet of the dehydration adsorption tower 8. The dehydration adsorption tower 8 contains a high-efficiency dehydrating agent, which can remove water vapor from the raw material hydrogen gas. After adsorption saturation, it can be desorbed and regenerated at high temperature. The outlet of the dehydration adsorption tower 8 is connected to a safety valve 9, which is then connected to the inlet of the second programmable valve 10. The outlet of the second programmable valve 10 is connected to the inlet of the first terminal filter 11, which filters the powder and particles generated during the adsorption process. The outlet of the first terminal filter 11 is connected to the second pressure gauge 12, which is then connected to the inlet of the product gas valve 13. The outlet of the product gas valve 13 is connected to the product gas outlet 14, ultimately leading to the gas consumption end.

[0020] Route 2 includes: a regenerated gas inlet 15, a second emergency shut-off valve 16, a second pressure reducing valve 17, a second mass flow meter 18, a third pressure gauge 19, a second filter 20, a heater 21, a third programmable valve 22, a water removal adsorption tower 8, a safety valve 9, an exhaust gas valve 23, a second terminal filter 24, a cooler 25, a fourth pressure gauge 26, a check valve 27, a flame arrester 28, and a rain cap 29. Regenerated gas enters the regenerated gas pipeline through the regenerated gas inlet 15, which is connected to the second emergency shut-off valve 16. The second emergency shut-off valve 16 is used for emergency handling during the regeneration process. The outlet 16 of the second emergency shut-off valve is connected to the inlet of the second pressure reducing valve 17, which reduces the pressure of the regenerated gas to the regeneration working pressure. The outlet of the second pressure reducing valve 17 is connected to the inlet of the second mass flow meter 18, which adjusts the gas flow rate according to working requirements. The outlet of the second mass flow meter 18 is connected to the third pressure gauge 19, which is then connected to the inlet of the second filter 20. The second filter 20 performs preliminary filtration of particulate matter in the regeneration gas. The outlet of the second filter 20 is connected to the inlet of the heater 21, which heats the regeneration gas to a temperature 100°C higher than the regeneration temperature of the high-efficiency dehydrating agent. The outlet of the heater 21 is connected to the inlet of the second programmable valve 22, and the outlet of the second programmable valve 22 is connected to the inlet of the dehydration adsorption tower 8, i.e., the outlet of the dehydration adsorption tower 8 in route 1. The high-efficiency dehydrating agent in the dehydration adsorption tower 8 can remove adsorbed water vapor at high temperature and discharge it as waste gas or raw material gas for other systems. The terminal outlet of the safety valve 9 above it is connected to the waste gas emission pipe. The outlet of the dehydration adsorption tower 8, i.e., the inlet of the dehydration adsorption tower 8 in route 1, is connected to the inlet of the waste gas emission valve 23. The outlet of the waste gas emission valve 23 is connected to the inlet of the second terminal filter 24, which filters the powder and particles generated during the desorption process. The outlet of the second terminal filter 24 is connected to the inlet of the cooler 25, which cools the high-temperature gas for safe discharge. The outlet of cooler 25 is connected to the fourth pressure gauge 26, and then to the inlet of check valve 27. Check valve 27 prevents atmospheric backflow and contamination of the pipeline. The outlet of check valve 27 is connected to flame arrester 28, which prevents flames from entering the system in the event of combustion other than hydrogen. After flame arrester 28, rain cap 29 is connected, followed by exhaust gas discharge. Rain cap 29 prevents water and solid impurities from entering the pipeline.

[0021] When water molecules enter the 3 Å pores of a 3A molecular sieve, they are adsorbed by the cations inside the sieve through a charge polarization effect. The smaller the radius and the higher the charge of the cation, the stronger the dipole moment polarization effect on the water molecules. Due to its polarity, the Class A molecular sieve exhibits strong selective adsorption of water molecules with a diameter of 2.7 Å, while it hardly adsorbs non-polar hydrogen gas with a diameter of 2.3 Å. Furthermore, due to its size, the 3A molecular sieve can be focused on a single application scenario of adsorbing water molecules. Adsorption is mainly divided into physical adsorption and chemical adsorption. Physical adsorption mainly relies on the polar induction force of van der Waals forces and electrostatic interactions between gas molecules, including water vapor, and the surface of the molecular sieve. Due to its specific pore size and shape, only gas molecules that meet the specific pore size and shape requirements of the molecular sieve can enter its internal channels, while other molecules are sieved and do not participate in adsorption. Chemical adsorption, on the other hand, significantly enhances adsorption stability because the silanol groups on the surface of the molecular sieve form hydrogen bonds with water molecules, allowing water molecules to be better adsorbed within the molecular sieve.

[0022] Before use, 3A molecular sieves should be activated and regenerated to remove adsorbed moisture, organic matter, etc., and restore their microporous adsorption capacity. Activation should be performed using a dry inert gas or vacuum heating to 250-350℃, held for 2-4 hours, and then cooled to below 80℃ under inert gas protection before use. When used for dehydration, the outlet dew point should be strictly monitored. If it exceeds the limit, the molecular sieve needs to be regenerated. Regeneration conditions are 0.13-0.15 MPa, with dry gas introduced for 3-4 hours, until the outlet dew point matches that of the regeneration gas. The dew point of the treated dry hydrogen gas is -60 to -70℃, 1-10 ppm or lower.

[0023] The operating procedure for the hydrogen dehydration system is as follows: ①Adsorption Open the product gas valve 13, the second programmable valve 10, the first programmable valve 7, and the first pressure reducing valve 3 in sequence, and close the remaining valves. The outlet pressure of the first pressure reducing valve 3 is 0.5~1 MPa. Adjust the first mass flow meter 4 to the operating flow rate. The raw material gas flows from the raw material gas inlet 1 through the water removal adsorption tower 8 from bottom to top. After water molecules are adsorbed by the micropores of the molecular sieve, dry hydrogen flows out from the top of the tower to the product gas outlet 14. Adsorption continues until the outlet hydrogen dew point rises to the set breakthrough point. Then, close the first pressure reducing valve 3, the product gas valve 13, the second programmable valve 10, and the first programmable valve 7 to end the adsorption process. Open the exhaust gas discharge valve 21 to discharge the gas to near atmospheric pressure, and then close the exhaust gas discharge valve 21.

[0024] ②Heating desorption Turn on heater 21 and preheat to the operating temperature. When the temperature approaches the set temperature, turn on cooler 25. Open exhaust valve 23. After the gas pressure drops to near atmospheric pressure, turn on third control valve 22 and second pressure reducing valve 17 in sequence. The outlet pressure of second pressure reducing valve 17 is 0.13-0.15 MPa. Adjust the flow rate of second mass flow meter 18 to the operating flow rate. The drying heating gas is heated to the target temperature by heater 21. The gas enters counter-currently from the top of the tower and flows down through the bed. The high-temperature gas heats the molecular sieve to about 200 ℃, and the moisture desorbs from the micropores of the molecular sieve and is discharged from the bottom of the tower with the hot gas flow. Continue heating until the dew point of the gas discharged from the exhaust pipe is -20 ℃, then stop heating.

[0025] ③ Cooling and Resetting Ambient temperature hydrogen dry gas is introduced from the top of the tower through the regeneration gas inlet 15 in reverse to purge the bed and reduce the temperature of the tubes and molecular sieves to below 40°C. The cooler 25 is then turned off. During the cooling process, a small amount of residual moisture and hot gas are carried out to the exhaust gas outlet. When the dew point is ≤-40°C and the bed temperature is stable, the exhaust gas outlet valve 23 is turned off.

[0026] ④Boost To prepare for the adsorption stage, dry hydrogen gas is introduced into the regeneration gas inlet 15 to raise the pressure inside the tower to 0.8 MPa, which is the adsorption pressure. After closing the second pressure reducing valve 17 and the third programmable valve 22, the status of the instruments is checked to see if they are normal. If they are normal, step ① adsorption can be repeated.

[0027] Due to the stringent hydrogen emission standards, the safety valve exhaust pipe is connected to the exhaust pipe, and no valve is allowed in the connected path to ensure the smooth exhaust of the safety valve.

[0028] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for purifying hydrogen in a semiconductor packaging and testing system, characterized in that, Includes the following steps: A water removal adsorption tower is provided. The water removal adsorption tower is a single tower body, which is divided into upper and lower layers. The upper layer is filled with 3A type spherical molecular sieves with a particle size of 2~3 mm, and the lower layer is filled with 3A type spherical molecular sieves with a particle size smaller than that of the upper layer. The two layers are separated by a honeycomb porous partition. The honeycomb porous partition is used to redistribute the airflow evenly, prevent channeling, and avoid the airflow directly impacting the lower molecular sieve. The method involves intermittently cyclically performing adsorption, heating desorption, cooling, and pressurization steps within the same water removal adsorption tower. During the adsorption stage, hydrogen gas containing moisture is introduced from the bottom of the dehydration adsorption tower. After the moisture is initially adsorbed by the upper molecular sieve, it is further deeply adsorbed by the lower molecular sieve to obtain dry hydrogen gas, which is then output from the top of the tower. When the outlet hydrogen dew point is detected to reach the set breakthrough point, adsorption stops and the regeneration stage begins. During the regeneration stage, the dry regeneration gas is heated to 200~350℃ by a heater and then introduced into the dehydration adsorption tower from the top of the tower to heat and desorb the molecular sieve. The desorbed moisture is discharged from the bottom of the tower. The regeneration pressure is 0.13~0.15MPa, the regeneration lasts for 2~4 hours, and the outlet temperature is >150℃ during the regeneration process. After desorption is completed, switch to room temperature dry regeneration gas to cool the adsorption tower until the temperature inside the tower drops below 40°C and the dew point of the outlet gas is ≤ –40°C. After cooling is complete, the pressure in the adsorption tower is increased to the adsorption working pressure to prepare for the next adsorption cycle.

2. The system for hydrogen purification in a semiconductor packaging and testing system according to claim 1, characterized in that, The system includes: a raw gas inlet path, a regenerated gas inlet path, and a water removal adsorption tower (8); The raw material gas inlet path is provided with a raw material gas inlet (1), a first emergency shut-off valve (2), a first pressure reducing valve (3), a first mass flow meter (4), a first pressure gauge (5), a first filter (6) and a first programmable valve (7) in sequence along the gas inlet direction. The outlet of the first programmable valve (7) is connected to the bottom inlet of the water removal adsorption tower (8). The top outlet of the water removal adsorption tower (8) is connected in sequence to a safety valve (9), a second programmable valve (10), a first terminal filter (11), a second pressure gauge (12), and a product gas valve (13), and finally leads to the product gas outlet (14). The regenerated gas inlet path is provided with a regenerated gas inlet (15), a second emergency shut-off valve (16), a second pressure reducing valve (17), a second mass flow meter (18), a third pressure gauge (19), a second filter (20), a heater (21), and a third programmable valve (22) in sequence along the inlet direction. The outlet of the third programmable valve (22) is connected to the top inlet of the water removal adsorption tower (8). The water removal adsorption tower is a single tower body, which is divided into upper and lower layers. The upper layer is filled with 3A type spherical molecular sieves with a particle size of 2~3 mm, and the lower layer is filled with 3A type spherical molecular sieves with a particle size smaller than that of the upper layer. The two layers are separated by a honeycomb porous partition. The honeycomb porous partition is used to redistribute the airflow evenly, prevent channeling, and avoid the airflow directly impacting the lower molecular sieve.

3. The system according to claim 2, characterized in that, The bottom outlet of the water removal adsorption tower (8) is also connected to a waste gas discharge path. The waste gas discharge path is provided with a waste gas discharge valve (23), a second terminal filter (24), a cooler (25), a fourth pressure gauge (26), a check valve (27), a flame arrester (28), and a rain cap (29) in sequence along the gas outlet direction.

4. The system according to claim 2, characterized in that, The first filter (6) and the second filter (20) use filters with a precision of 3 μm or 5 μm.

5. The system according to claim 2, characterized in that, The water removal adsorption tower (8) operates at room temperature and at a pressure of 0.3~1 MPa.

6. The system according to claim 2, characterized in that, The regeneration conditions of the water removal adsorption tower (8) are 0.13-0.15 MPa, inlet temperature 200-350 ℃, outlet temperature >150 ℃, for 2-4 h.

7. The system according to claim 2, characterized in that, The first terminal filter (11) and the second terminal filter (24) use filters with a precision of 1.5 μm.

8. The system according to claim 2, characterized in that, The first filter (6), the second filter (20), the first terminal filter (11), and the second terminal filter (24) are made of 316L sintered metal mesh.

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