Equipment for refining and purifying gas at low temperature

Abstract

The invention discloses equipment for refining and purifying gas at low temperature, which relates to the technical field of gas separation, refining and purification and comprises a shell container, an adsorber, heat exchange equipment and control equipment, the adsorber and the heat exchange equipment are arranged in the shell container, and the control equipment is arranged outside the shell container; wherein the shell container is of a double-layer jacket structure, the middle space and the inner space of the shell container provide a double-layer vacuum environment, the adsorber and the heat exchange equipment are located in the shell container, the inner vacuum environment provides a constant low-temperature environment for reaction in the adsorber, and meanwhile energy loss of the adsorber and the heat exchange equipment is effectively prevented during adsorption reaction and heat exchange reaction. The equipment and the adsorber in the equipment adopt a double-layer concentric jacket structure, and the jacket and the inner cylinder of the equipment adopt a double-vacuum mode, so that the cold loss of the equipment is avoided to the greatest extent, the energy consumption of the whole device is greatly reduced, and meanwhile, liquid nitrogen in the jacket of the adsorber can be used as an environmental cold source for adsorption reaction; and the raw material gas can also be used as a cold source for secondary cooling of the raw material gas, so that the number and scale of equipment are reduced.

Description

Technical Field

[0001] This invention relates to the field of gas separation, refining and purification technology, and more specifically to the field of equipment technology for low-temperature gas refining and purification. Background Technology

[0002] Currently, the main technologies in the field of industrial gas separation include pressure swing adsorption (PSA), membrane separation, and cryogenic separation. Among these, PSA is becoming the preferred technology due to its advantages such as low energy consumption, low cost, high automation, simple operation, and minimal susceptibility to external environmental influences. While most gases can be separated and purified at room temperature by utilizing the difference in selective adsorption capacity of adsorbents for different components in a gas mixture, further purification of gases with similar physical properties or certain high-purity rare gases is difficult. For example, the most common helium purification process contains trace amounts of hydrogen and neon.

[0003] Currently, mainstream gas purification processes primarily employ catalytic oxidation and low-temperature adsorption to remove impurities from high-purity gases. The former often results in complex processes, numerous equipment units, and large floor space; the latter requires multi-stage heat exchange, leading to lengthy heating and cooling times and significant energy consumption. Similarly, current low-temperature gas purification processes face challenges such as rapid cooling loss, high energy consumption, large floor space requirements, and the need to coordinate the deformation of core equipment due to temperature and pressure changes. Summary of the Invention

[0004] The purpose of this invention is to provide a device for low-temperature purification of gases in order to solve the above-mentioned technical problems.

[0005] To achieve the above objectives, the present invention specifically adopts the following technical solution: This invention provides a device for low-temperature gas purification, comprising an outer container, an adsorber, a heat exchanger, and a control device; the adsorber and the heat exchanger are disposed inside the outer container, and the control device is disposed outside the outer container. The outer container includes a first outer shell and a first inner shell fitted inside the first outer shell. The first inner shell and the first outer shell constitute a vacuum jacket structure, and the internal space of the first inner shell is a micro-vacuum environment. The adsorber is located inside the first inner shell. The adsorber includes a second outer shell and a second inner shell fitted inside the second outer shell. The second inner shell and the second outer shell form a jacket structure. The jacket structure is filled with liquid nitrogen. The internal space of the second inner shell is filled with adsorbent. A raw material gas inlet pipe communicating with the outside of the second outer shell is provided at the bottom of the second inner shell. A precooling coil serving as a bypass for the raw material gas inlet pipe is wound around the outer wall of the second inner shell inside the jacket structure. A loading and unloading port pipe and a product gas outlet pipe communicating with the top outside of the second outer shell are provided at the top of the second inner shell. The loading and unloading port pipe extends outside the outer shell container. A first airflow distributor cooperating with the raw material gas inlet pipe is provided at the bottom of the second inner shell. The heat exchanger is located inside the first inner shell at the bottom of the outer side of the adsorber and is used for heat exchange between the raw material gas and the product gas.

[0006] In one embodiment, the first outer shell includes a first outer cylinder and a first outer end cap disposed at the bottom of the first outer cylinder; The first inner shell includes a first inner cylinder, a first inner end cap disposed at the bottom of the first inner cylinder, and a top cover disposed at the top of the first inner cylinder; the top of the first inner cylinder is sealed to the top of the first outer cylinder through a flange and a clamp.

[0007] Specifically, the inner space of the outer container is sealed by the top cover, the first inner cylinder, and the first inner end cap, accommodating the adsorber and heat exchange equipment. During operation, its interior is in a micro-vacuum state (-0.03MPa to -0.099MPa). The vacuum jacket structure, formed by the first outer cylinder, the first outer end cap, the flange, and the outer wall of the first inner shell, creates a sealed space, also operating under vacuum. This effectively reduces the loss of internal cooling capacity. The outer container serves as the supporting shell for the entire equipment.

[0008] In one embodiment, a device support is provided at the bottom of the first outer casing, at least two device lifting lugs and a vacuum nozzle communicating with the inside of the vacuum jacket structure are provided on the outer side wall of the first outer casing, and a top cover lifting lug is provided on the top cover. The flange is located at the bottom of the top cover, and the flange is connected to the top cover by clamp bolts to achieve a quick-opening seal.

[0009] Specifically, this solution maintains the sealing performance of the internal space of the first inner shell while facilitating the inspection and maintenance of the internal adsorption and heat exchange equipment.

[0010] In one embodiment, the product gas outlet pipe is connected to the side wall of the loading / unloading port pipe, and a filled second airflow distributor is provided inside the loading / unloading port pipe. Filters are provided on both the raw material gas inlet pipe and the product gas outlet pipe.

[0011] Specifically, filters are installed on both the raw material gas inlet pipe and the product gas outlet pipe, which can effectively block the adsorbent from entering the pipeline and optimize the airflow distribution. The top-filled airflow distributor occupies the top non-flow space.

[0012] In one embodiment, the second inner shell and the second outer shell form a jacket structure, and the jacket structure is filled with liquid nitrogen. The bottom of the second outer shell is provided with a liquid nitrogen inlet that communicates with the interior of the jacket structure, the side wall of the second outer shell is provided with a liquid nitrogen replenishment inlet that communicates with the interior of the jacket structure, and the top of the second outer shell is provided with a nitrogen outlet that communicates with the interior of the jacket structure.

[0013] Specifically, the jacket structure of the adsorber is filled with liquid nitrogen, and the liquid nitrogen level is maintained through the liquid nitrogen replenishment port, the top nitrogen outlet, and the bottom liquid nitrogen connection port. The second inner shell provides a low-temperature environment for the adsorption process. During regeneration, there is no need to remove the liquid nitrogen environment. The desorption gas (which is the gas that is discharged after the adsorbent has absorbed the useless impurities in the process gas inside the adsorber, and then needs to be desorbed, i.e., regenerated, to remove the previously adsorbed impurities for the next adsorption) enters the heat exchanger directly from the raw material gas inlet pipe at the bottom of the adsorber to complete the heating, so that the entire equipment does not require external materials and energy for heating and cooling.

[0014] In one embodiment, a precooling raw material gas inlet and a precooling raw material gas outlet are provided on the side wall of the second outer shell, extending into the interior of the jacket structure and communicating with both ends of the precooling coil, respectively. The precooling coil is provided on the outer wall of the second inner shell near the raw material gas inlet. The precooling raw material gas inlet and the precooling raw material gas outlet are connected to the raw material gas inlet pipe at intervals. A valve and a temperature sensor are provided on the raw material gas inlet pipe between the precooling raw material gas inlet and the precooling raw material gas outlet.

[0015] Specifically, the precooling coil is connected in parallel to the bypass of the feed gas inlet pipe, which can precool the feed gas again. This allows the feed gas to undergo an additional precooling before entering the adsorber, providing a more stable and reliable temperature environment for the adsorption process.

[0016] After the raw gas from outside the boundary enters the equipment through the pipeline in the control area, it first passes through the high-efficiency heat exchanger of the heat exchange equipment. It is cooled by the low-temperature nitrogen generated by the vaporization of liquid nitrogen in the jacket of the adsorber. Before entering the adsorber, the inlet temperature of the cooled raw gas is determined by the temperature sensor to determine whether it reaches the adsorption temperature (below -180℃).

[0017] If the adsorption temperature is reached, the raw gas will directly enter from the bottom of the adsorber for adsorption. If the temperature is not reached, the raw gas will enter the adsorber jacket coil from the inlet bypass pre-cooled raw gas inlet for secondary cooling. After cooling, the raw gas will enter from the bottom of the adsorber for adsorption.

[0018] In one embodiment, the second outer shell is fixedly suspended on the top cover by several connecting rods and pins. The connecting rods include a flexible connecting rod in the middle and connecting rod seats at both ends of the flexible connecting rod. The pins are inserted into the connection between the flexible connecting rod and the connecting rod seats. The two connecting rod seats are respectively fixed to the bottom of the top cover and the top of the second outer shell.

[0019] Specifically, the adsorber is fixed and suspended on the top cover by several connecting rods and pins, so that it can deform freely with the cyclic load during operation, avoiding additional constraints that could cause equipment failure.

[0020] In one embodiment, an axially deformable temperature difference compensator is provided at the connection between the loading / unloading port and the top cover. The temperature difference compensator is sleeved on the loading / unloading port located outside the top cover. The lower end of the temperature difference compensator is welded to the top cover, and the upper end of the temperature difference compensator is welded to the loading / unloading port.

[0021] Specifically, the temperature difference compensator, under the premise of a sealed outer container, can accommodate the axial deformation of the top loading and unloading pipe caused by pressure or temperature changes.

[0022] In one embodiment, the heat exchanger is integrated at the bottom outer side of the adsorber. The raw gas inlet pipe is connected to the tube side or shell side of the heat exchanger, and the product gas outlet pipe is connected to the shell side or tube side of the heat exchanger. At the same time, a desorption gas branch line is provided to pre-cool the raw gas inlet pipe together with the product gas line. The raw gas inlet pipe and the product gas outlet pipe are connected to the outside of the first outer shell through the heat exchanger. The heat exchange equipment consists of one or more small, high-efficiency heat exchangers connected in series.

[0023] Specifically, the heat exchange equipment pre-cools or preheats the feed gas, product gas, and desorbed gas. In this solution, the adsorber is the main reaction equipment. After the reaction is completed, the product gas and desorbed gas are at low temperatures, while the incoming feed gas is at a high temperature. Therefore, the heat exchange equipment is used to cool the feed gas with the product gas and desorbed gas, which saves energy and eliminates the need for separate cooling of the feed gas. After the heat exchange is completed, the product gas leaves the outer container, and the desorbed gas is recirculated and incorporated into the feed gas for the next step of adsorption and purification.

[0024] In addition, the heat exchange equipment is located in a micro-vacuum environment inside the first inner shell of the outer shell container, which can minimize the loss of cooling capacity during heat exchange and significantly reduce the energy consumption of the device.

[0025] In one embodiment, the control equipment is located on the top cover. The control equipment integrates the regulating valves, programmable valves, manual valves, transmitters, and sensors, as well as other instrument accessories for the entire equipment's process control and monitoring. The control equipment areas of each process pipeline are either inside the outer casing or discharged outside the boundary area.

[0026] Specifically, process pipelines such as raw material gas, product gas, desorbed gas, liquid nitrogen, and nitrogen also enter the outer shell container or are discharged outside the boundary area from this area (control equipment area).

[0027] The beneficial effects of this invention are as follows: 1. This invention adopts a double-layer concentric jacket structure for both the equipment itself and the internal adsorber. The equipment jacket and inner cylinder adopt a double vacuum mode to minimize the loss of cold energy and significantly reduce the energy consumption of the entire device. At the same time, the liquid nitrogen in the adsorber jacket can serve as both an environmental cold source for the adsorption reaction and a cold source for the secondary cooling of the raw material gas, thus reducing the number and scale of equipment.

[0028] 2. This invention addresses the inner layer of the equipment's outer container by employing a double-layer seal at the junction of the top cover and flange, connected by clamp bolts in a quick-opening manner to maintain a micro-vacuum state within the inner container to the greatest extent possible. This structural design effectively preserves the sealing performance of the inner space, while the quick-opening mechanism facilitates the inspection and maintenance of the adsorption and heat exchange equipment inside the equipment, providing reliable convenience for the sealing and maintenance of the equipment during normal operation.

[0029] 3. This invention addresses the dual adverse conditions faced by the core component of the equipment, the adsorber, due to axial temperature difference strain and fatigue strain caused by internal pressure cyclic fluctuations. It optimizes the fixing structure by employing a flexible connecting rod + temperature difference compensator structure, allowing the adsorber to be "elastically" fixed to the top cover of the equipment. This significantly reduces the possibility of fatigue cracks caused by excessive strain due to local structural limitations, ensuring the safe and stable operation of the equipment. Attached Figure Description

[0030] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0031] Figure 1 This is a structural diagram of the main body of the device of the present invention; Figure 2 This is a structural diagram of the adsorber, the core device of this invention; Figure 3This is a structural diagram showing the flexible connection between the core device of this invention, the adsorber, and the top cover.

[0032] Figure 4 This is a schematic diagram of a heat exchange device.

[0033] Reference numerals: 1. Control equipment; 2. Outer container; 3. Adsorber; 4. Heat exchange equipment; 21. Top cover; 22. First outer end cap; 23. First inner end cap; 24. Vacuum nozzle; 25. First inner cylinder; 26. First outer cylinder; 27. Equipment lifting lug; 28. Flange; 29. ​​Clamping clamp; 31. Nitrogen outlet; 32. Second airflow distributor; 33. Precooled raw material gas outlet; 34. Precooling coil; 35. Precooled raw material gas inlet; 36. Liquid nitrogen connection port; 37. Raw material gas inlet pipe; 38. First airflow distributor; 39. Liquid nitrogen replenishment port; 310. Product gas outlet pipe; 311. Loading / unloading port pipe; 312. Temperature difference compensator; 313. Connecting rod seat; 314. Flexible connecting rod. Detailed Implementation

[0034] To make the technical problems, technical solutions, and technical effects of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0035] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0036] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0037] In the description of the embodiments of the present invention, it should be noted that the terms "inner", "outer", "upper", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the present invention.

[0038] Example 1 like Figures 1 to 3 As shown, this embodiment includes a device for low-temperature purification of gas, comprising an outer shell container 2, an adsorber 3, a heat exchanger 4, and a control device 1; the adsorber 3 and the heat exchanger 4 are disposed inside the outer shell container 2, and the control device 1 is disposed outside the outer shell container 2. The outer container 2 includes a first outer shell and a first inner shell fitted inside the first outer shell. The first inner shell and the first outer shell form a vacuum jacket structure, and the internal space of the first inner shell is a micro-vacuum environment. The adsorber 3 is located inside the first inner shell. The adsorber 3 includes a second outer shell and a second inner shell fitted inside the second outer shell. The second inner shell and the second outer shell form a jacket structure. The jacket structure is filled with liquid nitrogen. The internal space of the second inner shell is filled with adsorbent. A raw material gas inlet pipe 37 communicating with the outside of the second outer shell is provided at the bottom of the second inner shell. A precooling coil 34 serving as a bypass for the raw material gas inlet pipe 37 is wound around the outer wall of the second inner shell inside the jacket structure. A loading and unloading port pipe 311 communicating with the outside of the top of the second outer shell and a product gas outlet pipe 310 are provided at the top of the second inner shell. The loading and unloading port pipe 311 extends out of the outer shell container 2. A first airflow distributor 38 cooperating with the raw material gas inlet pipe 37 is provided at the bottom of the second inner shell. The heat exchanger 4 is located inside the first inner shell at the bottom outside the adsorber 3 and is used for heat exchange between the raw material gas and the product gas.

[0039] Example 2 This embodiment is a further optimization based on Embodiment 1, specifically: The first outer shell includes a first outer cylinder 26 and a first outer end cap 22 disposed at the bottom of the first outer cylinder 26; The first inner shell includes a first inner cylinder 25, a first inner end cap 23 disposed at the bottom of the first inner cylinder 25, and a top cover 21 disposed at the top of the first inner cylinder 25; the top of the first inner cylinder 25 is sealed to the top of the first outer cylinder 26 through a flange 28 and a clamp 29.

[0040] Specifically, the inner space of the outer container 2 is sealed by the top cover 21, the first inner cylinder 25, and the first inner end cap 23 to accommodate the adsorber 3 and the heat exchanger 4. During operation, its interior is in a micro-vacuum state (-0.03MPa to -0.099MPa). The vacuum jacket structure, formed by the first outer cylinder 26, the first outer end cap 22, the flange 28, and the outer wall of the first inner shell, creates a sealed space, also operating under vacuum. This effectively reduces the loss of internal cooling capacity. The outer container serves as the supporting shell for the entire equipment.

[0041] The bottom of the first outer casing is provided with an equipment support, and the outer side wall of the first outer casing is provided with at least two equipment lifting lugs 27 and a vacuum nozzle 24 that communicates with the inside of the vacuum jacket structure. The top cover 21 is provided with a top cover 21 lifting lug. Flange 28 is located at the bottom of top cover 21. Flange 28 is bolted to top cover 21 via clamp 29 to achieve quick-opening seal.

[0042] Specifically, this solution maintains the sealing performance of the internal space of the first inner shell while facilitating the inspection and maintenance of the internal adsorption equipment and heat exchange equipment 4.

[0043] The product gas outlet pipe 310 is connected to the side wall of the loading and unloading port pipe 311. A filling type second airflow distributor 32 is installed inside the loading and unloading port pipe 311. Filters are installed on both the raw material gas inlet pipe 37 and the product gas outlet pipe 310.

[0044] Specifically, filters are installed on both the raw material gas inlet pipe 37 and the product gas outlet pipe 310, which can effectively block the loaded adsorbent from entering the pipeline and also optimize the airflow distribution. The top-filled airflow distributor occupies the top non-flow space.

[0045] Example 3 This embodiment is a further optimization based on embodiment 2, specifically: The second inner shell and the second outer shell form a jacket structure, which is filled with liquid nitrogen. The bottom of the second outer shell is provided with a liquid nitrogen inlet 36 that communicates with the interior of the jacket structure, the side wall of the second outer shell is provided with a liquid nitrogen replenishment inlet 39 that communicates with the interior of the jacket structure, and the top of the second outer shell is provided with a nitrogen outlet 31 that communicates with the interior of the jacket structure.

[0046] Specifically, the jacket structure of the adsorber 3 is filled with liquid nitrogen, and the liquid nitrogen level is maintained through the liquid nitrogen replenishment port 39, the top nitrogen outlet 31, and the bottom liquid nitrogen connection port 36. The second inner shell provides a low-temperature environment for the adsorption process. During regeneration, there is no need to remove the liquid nitrogen environment. The desorption gas (which is the gas that is discharged after the adsorbent has absorbed the useless impurities in the process gas in the adsorber 3, and then needs to be desorbed, i.e., regenerated, to remove the previously adsorbed impurities for the next adsorption) enters the heat exchanger 4 directly from the raw material gas inlet pipe 37 at the bottom of the adsorber 3 to complete the heating. This means that the entire equipment does not require external materials or energy to heat or cool the equipment.

[0047] The second outer casing has a precooling raw material gas inlet 35 and a precooling raw material gas outlet 33 extending into the jacket structure and communicating with both ends of the precooling coil 34. The precooling coil 34 is located on the outer wall of the second inner casing near the raw material gas inlet. The precooling raw material gas inlet 35 and the precooling raw material gas outlet 33 are connected to the raw material gas inlet pipe 37 at intervals. A valve and a temperature sensor are provided on the raw material gas inlet pipe 37 between the precooling raw material gas inlet 35 and the precooling raw material gas outlet 33.

[0048] Specifically, the precooling coil 34 is connected in parallel to the bypass of the feed gas inlet pipe 37, which can precool the feed gas again. This allows the feed gas to be precooled once more before entering the adsorber 3, providing a more stable and reliable temperature environment for the adsorption process.

[0049] After the raw gas from outside the boundary enters the equipment through the pipeline in the control area, it first passes through the high-efficiency heat exchanger of the heat exchange equipment 4 and is cooled by the low-temperature nitrogen generated by the vaporization of liquid nitrogen in the jacket of the adsorber 3. Before entering the adsorber 3, the raw gas is cooled by the temperature sensor to determine whether the inlet temperature reaches the adsorption temperature (below -180℃).

[0050] If the adsorption temperature is reached, the raw gas will directly enter the adsorber 3 from the bottom raw gas inlet pipe 37 for adsorption. If the temperature does not reach the adsorption temperature, the raw gas will enter the jacket coil of the adsorber 3 from the inlet bypass pre-cooled raw gas inlet 35 for secondary cooling. After cooling, the raw gas will enter the adsorber 3 from the bottom raw gas inlet pipe 37 for adsorption.

[0051] Example 4 This embodiment is a further optimization based on embodiment 3, specifically: The second outer shell is fixed and suspended on the top cover 21 by several connecting rods and pins. The connecting rods include a flexible connecting rod 314 in the middle and connecting rod seats 313 at both ends of the flexible connecting rod 314. The pins are inserted into the connection between the flexible connecting rod 314 and the connecting rod seats 313. The two connecting rod seats 313 are fixed to the bottom of the top cover 21 and the top of the second outer shell, respectively.

[0052] Specifically, the adsorber 3 is fixed and suspended on the top cover 21 by several connecting rods and pins, so that it can deform freely with the cyclic load during operation, avoiding additional constraints that could cause equipment failure.

[0053] An axially deformable temperature difference compensator 312 is provided at the connection between the loading / unloading port pipe 311 and the top cover 21. The temperature difference compensator 312 is sleeved on the loading / unloading port pipe 311 located outside the top cover 21. The lower end of the temperature difference compensator 312 is welded to the top cover 21, and the upper end of the temperature difference compensator 312 is welded to the loading / unloading port pipe 311.

[0054] Specifically, the temperature difference compensator 312, under the premise of sealing the outer shell container 2, can adapt to the axial deformation of the top loading and unloading pipe caused by pressure or temperature changes.

[0055] Example 5 This embodiment is a further optimization based on embodiment 4, specifically: The heat exchanger 4 is integrated on the bottom outside of the adsorber 3. The raw material gas inlet pipe 37 is connected to the tube side or shell side of the heat exchanger 4, and the product gas outlet pipe 310 is connected to the shell side or tube side of the heat exchanger 4. The raw material gas inlet pipe 37 and the product gas outlet pipe 310 are connected to the outside of the first outer shell through the heat exchanger 4. Heat exchanger 4 is a single or multiple small, high-efficiency heat exchangers connected in series; Specifically, heat exchanger 4 precools or preheats the raw material gas, product gas, and desorbed gas. In this scheme, the adsorber 3 is the main reaction equipment. After the reaction is completed, the product gas that comes out is at a low temperature, while the raw material gas that comes in is at a high temperature. Therefore, heat exchanger 4 is used to cool the raw material gas with the product gas, which saves energy and eliminates the need for separate cooling of the raw material gas. After the heat exchange is completed, the product gas leaves the outer shell container 2.

[0056] In addition, the heat exchanger 4 is located in a micro-vacuum environment inside the first inner shell of the outer shell container 2, which can minimize the loss of cooling capacity during heat exchange and significantly reduce the energy consumption of the device.

[0057] Example 6 This embodiment is a further optimization based on embodiment 5, specifically: The control device 1 is located on the top cover 21. The control device 1 integrates the regulating valves, programmable valves, manual valves, transmitters and sensors and other instrument accessories for the entire equipment process control and monitoring. The control device 1 area of ​​each process pipeline enters the outer shell container 2 or is discharged outside the boundary area.

[0058] Specifically, process pipelines such as raw material gas, product gas, desorption gas, liquid nitrogen, and nitrogen also enter the outer shell container 2 or are discharged outside the boundary area from this area (control equipment 1 area).

[0059] Working principle: The vacuum jacket structure of the equipment is evacuated to a near-vacuum state through vacuum nozzle 24, while the inside of the first inner shell can be evacuated to a micro-vacuum state (-0.03MPa~-0.099MPa). The jacket structure of the adsorber 3 is filled with liquid nitrogen (filling coefficient of 0.5~0.8), and the inside of the second inner shell of the adsorber 3 is filled with special adsorbent. After the raw material gas from outside enters the equipment through the control area pipeline, it first passes through the high-efficiency heat exchanger of the heat exchange equipment 4, and is cooled by the low-temperature nitrogen generated by the vaporization of liquid nitrogen in the jacket of the adsorber 3. Before entering the adsorber 3, the inlet temperature of the cooled raw material gas is determined by a temperature sensor to determine whether it reaches the adsorption temperature (below -180℃).

[0060] If the adsorption temperature is reached, the gas enters directly from the raw material gas inlet pipe 37 at the bottom of the adsorber 3 for adsorption. If the temperature does not reach the adsorption temperature, the gas enters the jacketed coil of the adsorber 3 from the pre-cooled raw material gas inlet 35 for secondary cooling, and then enters from the raw material gas inlet pipe 37 at the bottom of the adsorber 3 for adsorption. The product gas (high-purity gas) after adsorption is discharged from the top of the adsorber 3 and passes through a second high-efficiency heat exchanger to pre-cool the raw material gas. At this time, a large amount of product gas is sent downstream through the product gas pipeline in the control area, while a small amount of product gas returns to the adsorber 3 to desorb and regenerate the adsorbent from top to bottom. The generated desorbed gas is discharged from the raw material gas inlet pipe 37 at the bottom of the adsorber 3, and after being pre-cooled by the heat exchanger, it is sent outside the equipment and heated to room temperature by the air temperature reheater. Then it enters the desorbed gas buffer tank, and after stabilization, it is circulated outside the equipment and merged into the raw material gas pipeline before entering the equipment again for purification.

Claims

1. A device for low-temperature purification of gases, characterized in that: It includes an outer shell container (2), an adsorber (3), a heat exchange device (4), and a control device (1); the adsorber (3) and the heat exchange device (4) are disposed inside the outer shell container (2), and the control device (1) is disposed outside the outer shell container (2); The outer shell container (2) includes a first outer shell and a first inner shell fitted inside the first outer shell. The first inner shell and the first outer shell constitute a vacuum jacket structure, and the internal space of the first inner shell is a micro-vacuum environment. The adsorber (3) is located inside the first inner shell. The adsorber (3) includes a second outer shell and a second inner shell fitted inside the second outer shell. The second inner shell and the second outer shell form a jacket structure. The jacket structure is filled with liquid nitrogen. The space inside the second inner shell is filled with adsorbent. The bottom of the second inner shell is provided with a raw material gas inlet pipe (37) that communicates with the outside of the second outer shell. The outer wall of the second inner shell inside the jacket structure is wrapped with a pre-cooling coil (34) that serves as a bypass for the raw material gas inlet pipe (37). The top of the second inner shell is provided with a loading and unloading port pipe (311) and a product gas outlet pipe (310) that communicate with the outside of the top of the second outer shell. The loading and unloading port pipe (311) extends out of the outer shell container (2). The bottom of the second inner shell is provided with a first airflow distributor (38) that cooperates with the raw material gas inlet pipe (37). The heat exchange device (4) is located inside the first inner shell at the bottom of the outer side of the adsorber (3) and is used for heat exchange between the raw material gas and the product gas.

2. The apparatus for low-temperature refining and purifying gas according to claim 1, characterized in that: The first outer shell includes a first outer cylinder (26) and a first outer end cap (22) disposed at the bottom of the first outer cylinder (26); The first inner shell includes a first inner cylinder (25), a first inner end cap (23) disposed at the bottom of the first inner cylinder (25), and a top cover (21) disposed at the top of the first inner cylinder (25); the top of the first inner cylinder (25) is sealed to the top of the first outer cylinder (26) through a flange (28) and a clamp (29).

3. The apparatus for low-temperature refining and purifying gas according to claim 2, characterized in that: The bottom of the first outer shell is provided with an equipment support, and the outer side wall of the first outer shell is provided with at least two equipment lifting lugs (27) and a vacuum nozzle (24) communicating with the inside of the vacuum jacket structure. The top cover (21) is provided with a top cover (21) lifting lug. The flange (28) is located at the bottom of the top cover (21), and the flange (28) and the top cover (21) are connected by bolts with clamps (29) to achieve a quick-opening seal.

4. The apparatus for low-temperature refining and purifying gas according to claim 1, characterized in that: The product gas outlet pipe (310) is connected to the side wall of the loading and unloading agent port pipe (311). A filling type second airflow distributor (32) is provided inside the loading and unloading agent port pipe (311). Filters are provided on both the raw material gas inlet pipe (37) and the product gas outlet pipe (310).

5. The apparatus for low-temperature refining and purifying gas according to claim 2, characterized in that: The second inner shell and the second outer shell form a jacket structure, and the jacket structure is filled with liquid nitrogen; The bottom of the second outer shell is provided with a liquid nitrogen communication port (36) communicating with the inside of the jacket structure, the side wall of the second outer shell is provided with a liquid nitrogen replenishment port (39) communicating with the inside of the jacket structure, and the top of the second outer shell is provided with a nitrogen outlet (31) communicating with the inside of the jacket structure.

6. The apparatus for low-temperature refining and purifying gas according to claim 5, characterized in that: The second outer shell has a precooling raw material gas inlet (35) and a precooling raw material gas outlet (33) extending into the jacket structure and communicating with both ends of the precooling coil (34). The precooling coil (34) is located on the outer wall of the second inner shell near the raw material gas inlet. The precooling raw material gas inlet (35) and the precooling raw material gas outlet (33) are connected to the raw material gas inlet pipe (37) at intervals. A valve and a temperature sensor are provided on the raw material gas inlet pipe (37) between the precooling raw material gas inlet (35) and the precooling raw material gas outlet (33).

7. The apparatus for low-temperature refining and purifying gas according to claim 2, characterized in that: The second outer shell is fixedly suspended on the top cover (21) by several connecting rods and pins. The connecting rods include a flexible connecting rod (314) in the middle and connecting rod seats (313) at both ends of the flexible connecting rod (314). The pins are inserted into the connection between the flexible connecting rod (314) and the connecting rod seats (313). The two connecting rod seats (313) are respectively fixed to the bottom of the top cover (21) and the top of the second outer shell.

8. The apparatus for low-temperature refining and purifying gas according to claim 7, characterized in that: An axially deformable temperature difference compensator (312) is provided at the connection between the loading / unloading port (311) and the top cover (21). The temperature difference compensator (312) is sleeved on the loading / unloading port (311) located outside the top cover (21). The lower end of the temperature difference compensator (312) is welded to the top cover (21), and the upper end of the temperature difference compensator (312) is welded to the loading / unloading port (311).

9. The apparatus for low-temperature refining and purifying gas according to claim 8, characterized in that: The heat exchange device (4) is integrated on the outer bottom of the adsorber (3). The raw material gas inlet pipe (37) is connected to the tube side or shell side of the heat exchange device (4), and the product gas outlet pipe (310) is connected to the shell side or tube side of the heat exchange device (4). The raw material gas inlet pipe (37) and the product gas outlet pipe (310) are connected to the outside of the first outer shell through the heat exchange device (4). The heat exchange device (4) is a single or multiple small, high-efficiency heat exchangers connected in series.

10. The apparatus for low-temperature refining and purifying gas according to claim 9, characterized in that: The control device (1) is located on the top cover (21). The control device (1) integrates regulating valves, programmable valves, manual valves, transmitters and sensors for the entire equipment process control and monitoring. The control device (1) area of ​​each process pipeline enters the outer shell container (2) or is discharged outside the boundary area.

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