Neon purification apparatus and neon purification method

Abstract

The present invention provides a neon purification apparatus and neon purification method that can improve the efficiency of regenerating the adsorption capacity of the moisture removal section. [Solution] The neon purification apparatus according to the present invention comprises: a hydrogen oxidation unit that oxidizes hydrogen in a raw material gas containing neon, helium, nitrogen, and hydrogen; a moisture removal unit that adsorbs and removes moisture generated in the hydrogen oxidation unit from the raw material gas; a nitrogen removal unit that adsorbs and removes nitrogen from the raw material gas from which moisture has been adsorbed and removed in the moisture removal unit; a helium removal unit that separates and removes helium from the raw material gas from which nitrogen has been adsorbed and removed in the nitrogen removal unit; a separation gas supply line capable of supplying the separation gas separated and removed from the raw material gas in the helium removal unit to the moisture removal unit; and a mixed gas supply line capable of supplying a mixed gas, which is a mixture of rinse gas supplied to the nitrogen removal unit and desorbed gas desorbed from the nitrogen removal unit, to the moisture removal unit.

Description

Technical Field

[0001] The present invention relates to a neon purification apparatus and a neon purification method.

Background Art

[0002] Conventionally, a neon purification apparatus for purifying neon from a raw material gas containing neon, helium, nitrogen, and hydrogen has been known. Patent Document 1 discloses this type of neon purification apparatus.

[0003] The neon purification apparatus described in Patent Document 1 includes a hydrogen oxidation unit that oxidizes hydrogen, a moisture removal unit that adsorbs and removes moisture, a liquefaction removal unit that liquefies and removes nitrogen, a removal unit that removes residual nitrogen and the like by low-temperature adsorption, and a distillation unit.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] When purifying neon using the neon purification apparatus described in Patent Document 1, in order to continue operation, it is conceivable to perform a regeneration process for regenerating the adsorption capacity of the moisture removal unit. However, the neon purification apparatus described in Patent Document 1 still has room for improvement from the viewpoint of efficiency when regenerating the adsorption capacity of the moisture removal unit.

[0006] An object of the present invention is to provide a neon purification apparatus and a neon purification method capable of improving the efficiency when regenerating the adsorption capacity of the moisture removal unit.

Means for Solving the Problems

[0007] The neon purification apparatus according to the first aspect of the present invention is (1) A hydrogen oxidation unit that oxidizes hydrogen in a raw material gas containing neon, helium, nitrogen, and hydrogen, A moisture removal unit that adsorbs and removes moisture generated in the hydrogen oxidation unit from the raw material gas, A nitrogen removal unit that adsorbs and removes nitrogen from the raw material gas from which moisture has been adsorbed and removed in the moisture removal unit, A helium removal unit separates and removes helium from the raw material gas from which nitrogen has been adsorbed and removed in the nitrogen removal unit, The neon purification apparatus comprises at least one of the following: a separation gas supply line capable of supplying the separation gas separated and removed from the raw material gas in the helium removal section to the moisture removal section; and a mixed gas supply line capable of supplying the moisture removal section with a mixed gas, which is a mixture of the rinse gas supplied to the nitrogen removal section and the desorbed gas removed from the nitrogen removal section.

[0008] A neon purification apparatus as one embodiment of the present invention is (2) The neon purification apparatus described in (1) above, comprising the separation gas supply line.

[0009] A neon purification apparatus as one embodiment of the present invention is (3) The neon purification apparatus described in (1) or (2) above, comprising the mixed gas supply line.

[0010] A second aspect of the present invention is a neon purification method, (4) A neon purification method using a neon purification apparatus, The neon purification apparatus is A hydrogen oxidation unit that oxidizes hydrogen in a raw material gas containing neon, helium, nitrogen, and hydrogen, A moisture removal unit that adsorbs and removes moisture generated in the hydrogen oxidation unit from the raw material gas, A nitrogen removal unit that adsorbs and removes nitrogen from the raw material gas from which moisture has been adsorbed and removed in the moisture removal unit, The system includes a helium removal unit that separates and removes helium from the raw material gas from which nitrogen has been adsorbed and removed in the nitrogen removal unit, A neon purification method in which at least one of the separated gas separated and removed from the raw material gas by the helium removal unit and the mixed gas in a state where the rinse gas supplied to the nitrogen removal unit and the desorbed gas desorbed from the nitrogen removal unit are mixed is supplied to the moisture removal unit.

[0011] A neon purification method as one embodiment of the present invention is (5) The neon purification method according to (4) above, in which the separated gas is supplied to the moisture removal unit.

[0012] A neon purification method as one embodiment of the present invention is (6) The neon purification method according to (4) or (5) above, in which the mixed gas is supplied to the moisture removal unit.

Advantages of the Invention

[0013] According to the present invention, it is possible to provide a neon purification apparatus and a neon purification method capable of improving the efficiency when regenerating the adsorption capacity of the moisture removal unit.

Brief Description of the Drawings

[0014] [Figure 1] It is a diagram showing a neon purification apparatus according to a first embodiment of the present invention. [Figure 2] It is a diagram showing a neon purification apparatus according to a second embodiment of the present invention.

Embodiments for Carrying Out the Invention

[0015] Hereinafter, embodiments of a neon purification apparatus and a neon purification method according to the present invention will be illustrated and described with reference to the drawings. The same components are denoted by the same reference numerals in each figure.

[0016] <First Embodiment> Figure 1 shows a neon purification apparatus 100 as one embodiment of the neon purification apparatus according to the present invention. Crude neon gas containing neon, helium, nitrogen, and hydrogen is supplied to the neon purification apparatus 100. The neon purification apparatus 100 is a device that purifies neon from this crude neon gas. Crude neon gas is produced as a byproduct when producing oxygen, nitrogen, and argon from raw air using an air separation device. The main composition of the crude neon gas supplied to the neon purification apparatus 100 is, for example, 50 vol% neon, 15 vol% helium, 2 vol% hydrogen, and the remainder nitrogen. However, the composition of the crude neon gas is not limited to the above and may vary depending on the configuration of the air separation device that produces the crude neon gas.

[0017] Buffer container 1 receives crude neon gas supplied from crude neon gas supply line 101 and reflux gas that is refluxed as part of the process of neon purification apparatus 100, and these The mixture is stored and held as the raw material gas. Examples of reflux gases include, but are not limited to, the gas exhausted from the moisture removal section 6, the gas exhausted from the nitrogen removal section 7, and the gas exhausted from the distillation column 13. The buffer container 1 may not accept reflux gas and may store only crude neon gas as the raw material gas. The neon purification apparatus 100 does not need to have a buffer container 1. In this case, the crude neon gas and reflux gas may be mixed, for example, in the crude neon gas supply line 101 and used as the raw material gas.

[0018] The raw material gas discharged from the buffer container 1 is pressurized to the pressure required for the process by the compressor 2. The pressurized raw material gas is introduced into the hydrogen oxidation section 3. The raw material gas introduced into the hydrogen oxidation section 3 may be heated by a heater before being introduced into the hydrogen oxidation section 3, or it may be heated by a heater provided in the hydrogen oxidation section 3 after being introduced into the hydrogen oxidation section 3. In addition, oxygen gas is added to the raw material gas before it is introduced into the hydrogen oxidation section 3. As a result, the hydrogen and oxygen in the raw material gas react in the hydrogen oxidation section 3, and water is produced by the oxidation of hydrogen. The hydrogen oxidation section 3 is equipped with a catalyst that promotes the reaction between hydrogen and oxygen. In this embodiment, the hydrogen oxidation section 3 includes a hydrogen oxidation tower, and the catalyst is packed inside the hydrogen oxidation tower. Examples of catalysts include platinum, palladium, and copper, but are not limited to these. The raw material gas whose temperature has risen due to the reaction heat of the catalytic reaction in the hydrogen oxidation section 3 is introduced into a cooler 4 and cooled to below room temperature. The raw material gas cooled by the cooler 4 is introduced into the ambient temperature gas-liquid separator 5. This separates the water that has condensed due to cooling in the cooler 4 into the liquid phase, and the other components into the gas phase.

[0019] The raw material gas separated into the gas phase in the ambient temperature gas-liquid separator 5 is introduced into the moisture removal unit 6. The moisture removal unit 6 is a device that removes moisture and carbon dioxide from the raw material gas using a thermal swing adsorption (TSA) method (hereinafter simply referred to as the "TSA method"), which involves repeated adsorption and regeneration due to temperature differences.

[0020] The moisture removal unit 6 is equipped with an adsorbent. This adsorbent adsorbs and removes moisture and carbon dioxide from the raw material gas. The moisture adsorbed and removed in the moisture removal unit 6 is produced in the hydrogen oxidation unit 3 when hydrogen contained in the raw material gas reacts with oxygen. The carbon dioxide adsorbed and removed in the moisture removal unit 6 is produced in the hydrogen oxidation unit 3 when carbon monoxide contained in the raw material gas reacts with oxygen. Examples of adsorbents used in the moisture removal unit 6 include, but are not limited to, zeolite, silica gel, and activated alumina.

[0021] The moisture removal unit 6 of this embodiment includes at least two adsorption towers. Each of the at least two adsorption towers is filled with the adsorbent described above. During operation of the neon purification apparatus 100, an adsorption process is performed in at least one of the at least two adsorption towers to adsorb and remove moisture and carbon dioxide from the raw gas, and a regeneration process is performed in the other at least one adsorption tower to dehydrate moisture and carbon dioxide from the adsorbent. This adsorption process and regeneration process are performed by switching between the at least two adsorption towers of the moisture removal unit 6. In the regeneration process, a regeneration gas is supplied to the moisture removal unit 6 to promote the dehydration of moisture and carbon dioxide from the adsorbent. This regeneration gas may be supplied to the moisture removal unit 6 in a heated state by an external heater or the like.

[0022] The neon purification apparatus 100 of this embodiment includes a separation gas supply line 103 capable of supplying the separation gas, which has been separated and removed from the raw material gas in the helium removal unit 11 (described later), to the moisture removal unit 6, and a mixed gas supply line 110 capable of supplying a mixed gas, which is a mixture of rinse gas supplied to the nitrogen removal unit 7 (described later) and desorbed gas removed from the nitrogen removal unit 7, to the moisture removal unit 6. Specifically, the separation gas supply line 103 is a line connecting the helium removal unit 11 and the moisture removal unit 6. The mixed gas supply line 110 is a line connecting the nitrogen removal unit 7 and the moisture removal unit 6. Therefore, according to the neon purification apparatus 100 of this embodiment, the separation gas as regenerated gas is supplied to the moisture removal unit 6 through the separation gas supply line 103. This is possible. Furthermore, according to the neon purification apparatus 100 of this embodiment, the mixed gas as regenerated gas can be supplied to the moisture removal unit 6 through the mixed gas supply line 110.

[0023] The neon purification apparatus 100 may be configured to include a separation gas supply line 103 but not a mixed gas supply line 110. Alternatively, the neon purification apparatus 100 may be configured to include a mixed gas supply line 110 but not a separation gas supply line 103. In other words, the neon purification apparatus 100 only needs to include at least one of the separation gas supply line 103 and the mixed gas supply line 110.

[0024] Conventionally, it was common practice to prepare a separate dry gas in addition to the crude neon gas and use this dry gas as a regeneration gas to regenerate the adsorption capacity of the moisture removal unit 6. However, this conventional method had the problem of increasing operating costs because it required the preparation of a separate dry gas in addition to the crude neon gas. In contrast, the neon purification apparatus 100 is equipped with at least one of a separation gas supply line 103 and a mixed gas supply line 110. This allows at least one of the separation gas and the mixed gas to be used as a regeneration gas, reducing the amount of dry gas required for regeneration that is prepared separately from the crude neon gas, or eliminating the need to prepare and use such dry gas altogether. Moreover, since the main component of the separation gas is helium and the main component of the mixed gas is nitrogen, even when at least one of the separation gas and the mixed gas is used as a regeneration gas, the neon recovery rate from the crude neon gas is not likely to decrease. In other words, by including at least one of the separation gas supply line 103 and the mixed gas supply line 110 in the neon purification apparatus 100, it is possible to regenerate the adsorption capacity of the moisture removal unit 6 while simultaneously suppressing the decrease in neon recovery rate and suppressing the increase in operating costs. That is, the efficiency of regenerating the adsorption capacity of the moisture removal unit 6 can be improved.

[0025] In this embodiment, the separated gas supply line 103 has a connection line 150 connected to the moisture removal unit 6. Similarly, the mixed gas supply line 110 in this embodiment also has a connection line 150 connected to the moisture removal unit 6. In other words, the separated gas supply line 103 and the mixed gas supply line 110 in this embodiment share the connection line 150 with each other. However, the separated gas supply line 103 and the mixed gas supply line 110 may not share any portion with each other and may be provided as separate lines.

[0026] Furthermore, if necessary, a portion of the raw material gas from which moisture and carbon dioxide have been removed in the moisture removal unit 6 can be used as regenerated gas.

[0027] In the regeneration process of the moisture removal unit 6, the moisture and carbon dioxide removed from the adsorbent are mixed with the regeneration gas and, together with the blowdown gas generated during the switching between the adsorption and regeneration processes, are discharged from the moisture removal unit 6 through the exhaust line 104. At this time, at least a portion of the gas discharged from the moisture removal unit 6 through the exhaust line 104 may be supplied to the buffer container 1 as reflux gas to improve the neon recovery rate. Alternatively, all of the gas discharged from the moisture removal unit 6 through the exhaust line 104 may be discharged outside the neon purification apparatus 100 system.

[0028] The raw material gas from which water and carbon dioxide have been removed by the water removal unit 6 is introduced into the nitrogen removal unit 7. In the nitrogen removal unit 7, most of the nitrogen contained in this raw material gas is removed. Specifically, the nitrogen removal unit 7 of this embodiment is a device that removes nitrogen from the raw material gas by a pressure swing adsorption (VPSA) method (hereinafter simply referred to as the "VPSA method") which repeats adsorption and regeneration by pressure swing using a vacuum pump. However, the nitrogen removal unit 7 may also be a TSA method, or a pressure swing adsorption (PSA) method (hereinafter simply referred to as the "PSA method") which does not use a vacuum pump.

[0029] The nitrogen removal unit 7 is equipped with an adsorbent. Examples of adsorbents for the nitrogen removal unit 7 include, but are not limited to, zeolite and activated carbon. The nitrogen removal unit 7 in this embodiment is equipped with at least two adsorption towers. Each of these at least two adsorption towers is filled with the above-mentioned adsorbent. It is preferable that the nitrogen removal unit 7 is equipped with three or more adsorption towers to reduce neon loss. During operation of the neon purification apparatus 100, an adsorption process is performed in at least one adsorption tower to remove nitrogen from the raw gas, and a regeneration process is performed in at least one other adsorption tower to desorb the nitrogen adsorbed on the adsorbent. This adsorption process and regeneration process are performed by switching between at least two adsorption towers of the nitrogen removal unit 7. In addition, in order to improve the neon recovery rate, a pressure equalization process may be performed at the end of the adsorption process to distribute the pressure of the adsorption tower in which the adsorption process was performed to another adsorption tower.

[0030] The regeneration process performed in the nitrogen removal unit 7 may include a depressurization process, a vacuum evacuation process, and an exhaust gas regeneration process. The depressurization process is a process of releasing the pressure remaining in the adsorption tower to the outside after the adsorption process, or after the pressure equalization process if a pressure equalization process is performed after the adsorption process. The vacuum evacuation process is a process of desorbing nitrogen adsorbed on the adsorbent by vacuum evacuating the adsorption tower using a vacuum pump. The exhaust gas regeneration process is a process of further promoting nitrogen desorption by flowing rinse gas through the adsorption tower while vacuum evacuating the adsorption tower using a vacuum pump. Here, it is desirable that the gas used as the rinse gas is a gas that does not contain nitrogen, and in this embodiment, a portion of the raw material gas from which most of the nitrogen has been removed by the nitrogen removal unit 7 is used. Specifically, a portion of the raw material gas from which most of the nitrogen has been removed by the nitrogen removal unit 7 is supplied to the nitrogen removal unit 7 as rinse gas through a rinse gas supply line 105 that branches off from a connection line 151 connecting the nitrogen removal unit 7 and the first heat exchanger 8, which will be described later.

[0031] As described above, the desorbed gases such as nitrogen removed from the adsorbent in the nitrogen removal section 7 during the regeneration process are mixed with rinse gas supplied to the nitrogen removal section 7 and discharged from the nitrogen removal section 7 as a mixed gas. The mixed gas may also contain blowdown gas released from the adsorption tower during the depressurization process. At least a portion of the mixed gas may be supplied to the moisture removal section 6 as regenerated gas through the mixed gas supply line 110. If only a portion of the mixed gas is supplied to the moisture removal section 6 through the mixed gas supply line 110, the remainder of the mixed gas is discharged from the nitrogen removal section 7 through the exhaust line 106 branching off from the mixed gas supply line 110. If the mixed gas is not supplied to the moisture removal section 6, all of the mixed gas is discharged from the nitrogen removal section 7 through the exhaust line 106 branching off from the mixed gas supply line 110. At least a portion of the mixed gas discharged from the nitrogen removal section 7 through the exhaust line 106 may be supplied to the buffer container 1 as reflux gas to improve the neon recovery rate. Furthermore, the mixed gas discharged from the nitrogen removal unit 7 through the exhaust line 106 may all be discharged outside the neon purification unit 100 system.

[0032] As shown in Figure 1, the neon purification apparatus 100 includes a cold box 20. Some of the elements constituting the neon purification apparatus 100 are located inside the cold box 20. The inside of the cold box 20 is cooled by a circulating refrigerant supplied from a cryogenic refrigerator 21 to the first heat exchanger 8 and the second heat exchanger 10 inside the cold box 20. Therefore, the elements located inside the cold box 20 are maintained at a lower temperature than the elements located outside the cold box 20. Specifically, in the neon purification apparatus 100 of this embodiment, the first heat exchanger 8, auxiliary nitrogen removal unit 9, second heat exchanger 10, helium removal unit 11, expansion valve 12, distillation column 13, and reboiler 14 are located inside the cold box 20 and are maintained at a lower temperature than the buffer container 1, compressor 2, hydrogen oxidation unit 3, cooler 4, ambient temperature gas-liquid separator 5, moisture removal unit 6, and nitrogen removal unit 7, which are not located inside the cold box 20.

[0033] The raw material gas, from which most of the nitrogen has been removed by the nitrogen removal unit 7, is introduced into the first heat exchanger 8 in the cold box 20. The raw material gas is introduced into the first heat exchanger 8 as a warm fluid and is cooled by the first heat exchanger 8 to a temperature, for example, between 44K and 100K. The neon purification apparatus 100 of this embodiment is equipped with a cryogenic refrigerator 21. The first heat exchanger 8 is supplied with a circulating refrigerant from the cryogenic refrigerator 21. The cryogenic refrigerator 21 may, but is not limited to, a Brayton cycle. As the circulating refrigerant, for example, helium, neon, hydrogen, or a mixture of several of these can be used.

[0034] The raw material gas cooled in the first heat exchanger 8 is introduced into the auxiliary nitrogen removal unit 9. The auxiliary nitrogen removal unit 9 is equipped with an adsorbent and removes trace amounts of nitrogen from the raw material gas that were not removed by the nitrogen removal unit 7. The nitrogen concentration in the raw material gas introduced into the auxiliary nitrogen removal unit 9 is preferably 100 vol ppm or less, and more preferably 10 vol ppm or less. Examples of adsorbents for the auxiliary nitrogen removal unit 9 include, but are not limited to, zeolite and activated carbon. The auxiliary nitrogen removal unit 9 may be designed so that its performance can be maintained by performing a regeneration process when the entire device is returned to room temperature, such as during periodic inspections. The auxiliary nitrogen removal unit 9 may also be provided in multiple sections. In this embodiment, the auxiliary nitrogen removal unit 9 removes nitrogen from the raw material gas so that the nitrogen concentration in the raw material gas is at least 100 vol ppb or less.

[0035] The raw material gas from which nitrogen has been removed in the auxiliary nitrogen removal unit 9 is introduced into the second heat exchanger 10. The raw material gas is introduced into the second heat exchanger 10 as a warm fluid and is cooled by the second heat exchanger 10 to a temperature, for example, between 25K and 44K. The second heat exchanger 10 is supplied with circulating refrigerant from the cryogenic refrigerator 21 via the first heat exchanger 8. In Figure 1, the circulating refrigerant from the cryogenic refrigerator 21 is shown circulating through the first heat exchanger 8 and the second heat exchanger 10, which are connected in series with the cryogenic refrigerator 21. However, the circulating refrigerant from the cryogenic refrigerator 21 may also circulate through the first heat exchanger 8 and the second heat exchanger 10, which are connected in parallel with the cryogenic refrigerator 21. In addition, separate refrigerators may be provided for each of the first heat exchanger 8 and the second heat exchanger 10.

[0036] The raw material gas cooled in the second heat exchanger 10 is introduced into the helium removal unit 11. The helium removal unit 11 removes helium from the raw material gas. Specifically, the helium removal unit 11 in this embodiment is a low-temperature gas-liquid separator that separates the raw material gas into a separation liquid mainly composed of neon and a separation gas mainly composed of helium. At least a portion of the separation gas removed from the raw material gas in the helium removal unit 11 may be supplied to the moisture removal unit 6 as regenerated gas through the separation gas supply line 103. If only a portion of the separation gas is supplied to the moisture removal unit 6 through the separation gas supply line 103, the remainder of the separation gas is discharged from the helium removal unit 11 through the exhaust line 152 branching off from the separation gas supply line 103. If the separation gas is not supplied to the moisture removal unit 6, all of the separation gas is discharged from the helium removal unit 11 through the exhaust line 152 branching off from the separation gas supply line 103. At least a portion of the separated gas discharged from the helium removal unit 11 through the exhaust line 152 may be supplied to the buffer container 1 as reflux gas to improve the neon recovery rate. Alternatively, all of the mixed gas discharged from the helium removal unit 11 through the exhaust line 152 may be discharged outside the neon purification apparatus 100 system.

[0037] The separation liquid, mainly composed of neon, separated in the helium removal section 11, is introduced into the expansion valve 12. This separation liquid is depressurized by Joule-Thomson expansion in the expansion valve 12 and then introduced into the top side of the distillation column 13. In the distillation column 13, helium is further removed from the raw material gas, i.e., the separation liquid, from which the separation gas mainly composed of helium has been separated in the helium removal section 11. Specifically, when the raw material gas is supplied to the distillation column 13, neon gas containing helium is concentrated at the top of the column, and high-purity neon of 99 vol% or more is concentrated at the bottom of the column. Purified neon is extracted from the bottom of the distillation column 13 and compressed by a compressor 15 to be extracted as product neon. If the product neon is extracted from the distillation column 13 in liquid form, a liquid transfer pump may be used instead of the compressor 15. Alternatively, the product neon may be extracted without using the compressor 15. The distillation column 13 is equipped with a reboiler 14 that vaporizes the descending liquid to produce rising gas. The distillation column 13 may be a regularly packed column, an irregularly packed column, or a tray column. The heating method for the reboiler 14 may include, but is not limited to, a heating method using an electric heater or a heating method using another hot fluid via a heat exchanger. Although not shown in Figure 1, the distillation column 13 may be equipped with a condenser that cools the rising gas to produce descending liquid. Furthermore, the neon purification apparatus 100 of this embodiment is equipped with a distillation column gas reflux line 107 that can introduce the helium-containing distillation column gas exiting from the top of the distillation column 13 into a buffer container 1. Since this distillation column gas contains more than 80 vol% neon, the recovery rate of neon can be improved by refluxing the distillation column gas.

[0038] Next, a neon purification method using the neon purification apparatus 100, as one embodiment of the neon purification method according to the present invention, will be described. In the neon purification method using the neon purification apparatus 100, at least one of the separated gas separated and removed from the raw material gas in the helium removal section 11, and the mixed gas obtained by mixing the rinse gas supplied to the nitrogen removal section 7 and the desorbed gas desorbed from the nitrogen removal section 7, is supplied to the moisture removal section 6. This makes it possible to regenerate the adsorption capacity of the moisture removal section 6 while simultaneously suppressing a decrease in the neon recovery rate and suppressing an increase in operating costs. In other words, the efficiency of regenerating the adsorption capacity of the moisture removal section 6 can be improved.

[0039] <Second Embodiment> Figure 2 shows a neon purification apparatus 300 as one embodiment of the neon purification apparatus according to the present invention. Crude neon gas containing neon, helium, nitrogen, and hydrogen is supplied to the neon purification apparatus 300. The neon purification apparatus 300 is a device that purifies neon from this crude neon gas. Crude neon gas is produced as a byproduct when producing oxygen, nitrogen, and argon from raw air using an air separation device. The main composition of the crude neon gas supplied to the neon purification apparatus 300 is, for example, 50 vol% neon, 15 vol% helium, 2 vol% hydrogen, and the remainder nitrogen. However, the composition of the crude neon gas is not limited to the above and may vary depending on the configuration of the air separation device that produces the crude neon gas.

[0040] The buffer container 61 receives crude neon gas supplied from the crude neon gas supply line 301 and reflux gas refluxed in part of the process of the neon purification unit 300, and stores and retains the mixture of these as the raw material gas. The reflux gas may include, but is not limited to, the gas exhausted from the moisture removal unit 66, the gas exhausted from the nitrogen removal unit 71, and the gas exhausted from the distillation column 76. The buffer container 61 may not accept the reflux gas and may only store crude neon gas as the raw material gas. Furthermore, the neon purification unit 300 does not need to have a buffer container 61. In this case, the crude neon gas and reflux gas may be mixed, for example, in the crude neon gas supply line 301 and used as the raw material gas.

[0041] The raw material gas discharged from the buffer container 61 is pressurized to the pressure required for the process by the compressor 62. The raw material gas pressurized by the compressor 62 is supplied to the hydrogen oxidation section 63. The raw material gas introduced into the hydrogen oxidation section 63 may be heated by a heater before being introduced into the hydrogen oxidation section 63, or it may be heated by a heater provided in the hydrogen oxidation section 63 after being introduced into the hydrogen oxidation section 63. Oxygen gas is added to the raw material gas before it is introduced into the hydrogen oxidation section 63. As a result, hydrogen and oxygen in the raw material gas react in the hydrogen oxidation section 63, and water is produced by the oxidation of hydrogen. The apparatus includes a catalyst to promote the reaction. The hydrogen oxidation section 63 of this embodiment includes a hydrogen oxidation tower, and the catalyst is packed inside the hydrogen oxidation tower. Examples of catalysts include platinum, palladium, and copper, but are not limited to these. The raw material gas, whose temperature has risen due to the reaction heat of the catalytic reaction in the hydrogen oxidation section 63, is introduced into a cooler 64 and cooled to below room temperature. The raw material gas cooled by the cooler 64 is introduced into a room-temperature gas-liquid separator 65. As a result, the water condensed by the cooling in the cooler 64 is separated into the liquid phase, and the other components are separated into the gas phase.

[0042] The raw material gas separated into the gas phase in the ambient temperature gas-liquid separator 65 is introduced into the moisture removal unit 66. The moisture removal unit 66 is a device that removes moisture and carbon dioxide from the raw material gas using a TSA method that repeatedly adsorbs and regenerates due to temperature differences.

[0043] The moisture removal unit 66 is equipped with an adsorbent. This adsorbent adsorbs and removes moisture and carbon dioxide from the raw material gas. The moisture adsorbed and removed in the moisture removal unit 66 is produced in the hydrogen oxidation unit 63 when hydrogen contained in the raw material gas reacts with oxygen. The carbon dioxide adsorbed and removed in the moisture removal unit 66 is produced in the hydrogen oxidation unit 63 when carbon monoxide contained in the raw material gas reacts with oxygen. Examples of adsorbents for the moisture removal unit 66 include, but are not limited to, zeolite, silica gel, and activated alumina.

[0044] The moisture removal unit 66 of this embodiment includes at least two adsorption towers. Each of the at least two adsorption towers is filled with the adsorbent described above. During operation of the neon purification apparatus 300, an adsorption process is performed in at least one of the at least two adsorption towers to adsorb and remove moisture and carbon dioxide from the raw gas, and a regeneration process is performed in the other at least one adsorption tower to dehydrate moisture and carbon dioxide from the adsorbent. This adsorption process and regeneration process are performed by switching between the at least two adsorption towers of the moisture removal unit 66. In the regeneration process, a regeneration gas is supplied to the moisture removal unit 66 to promote the dehydration of moisture and carbon dioxide from the adsorbent. This regeneration gas may be supplied to the moisture removal unit 66 in a heated state by an external heater or the like.

[0045] The neon purification apparatus 300 of this embodiment includes a separation gas supply line 303 capable of supplying the separation gas, which has been separated and removed from the raw material gas in the helium removal unit 73 (described later), to the moisture removal unit 66, and a mixed gas supply line 310 capable of supplying the moisture removal unit 66 a mixed gas, which is a mixture of rinse gas supplied to the nitrogen removal unit 71 (described later) and desorbed gas removed from the nitrogen removal unit 71. Specifically, the separation gas supply line 303 is a line connecting the helium removal unit 73 and the moisture removal unit 66. The mixed gas supply line 310 is a line connecting the nitrogen removal unit 71 and the moisture removal unit 66. Therefore, according to the neon purification apparatus of this embodiment, the separation gas as regenerated gas can be supplied to the moisture removal unit 66 through the separation gas supply line 303. Furthermore, according to the neon purification apparatus of this embodiment, the mixed gas as regenerated gas can be supplied to the moisture removal unit 66 through the mixed gas supply line 310.

[0046] Furthermore, the neon purification apparatus 300 may be configured to include a separation gas supply line 303 but not a mixed gas supply line 310. Alternatively, the neon purification apparatus 300 may be configured to include a mixed gas supply line 310 but not a separation gas supply line 303. In other words, the neon purification apparatus 300 only needs to include at least one of the separation gas supply line 303 and the mixed gas supply line 310.

[0047] Conventionally, it was common to prepare a dry gas separately from the crude neon gas and use this dry gas as a regeneration gas to regenerate the adsorption capacity of the moisture removal unit 66. However, this conventional method had the problem of increasing operating costs because it required preparing a dry gas separately from the crude neon gas. In contrast, the neon purification apparatus 300 uses a separation gas The neon refining apparatus 300 is equipped with at least one of the separation gas supply line 303 and the mixed gas supply line 310. This allows at least one of the separation gas and the mixed gas to be used as a regeneration gas, reducing the amount of dry gas required for regeneration gas, which is prepared separately from the crude neon gas, or eliminating the need to prepare and use such dry gas altogether. Moreover, since the main component of the separation gas is helium and the main component of the mixed gas is nitrogen, even when at least one of the separation gas and the mixed gas is used as a regeneration gas, the neon recovery rate from the crude neon gas is not likely to decrease. In other words, by equipping the neon refining apparatus 300 with at least one of the separation gas supply line 303 and the mixed gas supply line 310, it is possible to regenerate the adsorption capacity of the moisture removal unit 66 while simultaneously suppressing the decrease in the neon recovery rate and suppressing the increase in operating costs. That is, the efficiency of regenerating the adsorption capacity of the moisture removal unit 6 can be improved.

[0048] In this embodiment, the separated gas supply line 303 has a connecting line 350 connected to the moisture removal unit 66. Similarly, the mixed gas supply line 310 in this embodiment also has a connecting line 350 connected to the moisture removal unit 66. In other words, the separated gas supply line 303 and the mixed gas supply line 310 in this embodiment share the connecting line 350 with each other. However, the separated gas supply line 303 and the mixed gas supply line 310 may not share any portion with each other and may be provided as separate lines.

[0049] Furthermore, if necessary, a portion of the raw material gas from which moisture and carbon dioxide have been removed in the moisture removal unit 66 can be used as regenerated gas.

[0050] In the regeneration process of the moisture removal unit 66, the moisture and carbon dioxide removed from the adsorbent are mixed with the regeneration gas and, together with the blowdown gas generated during the switching between the adsorption and regeneration processes, are discharged from the moisture removal unit 66 through the exhaust line 314. At this time, at least a portion of the gas discharged from the moisture removal unit 66 through the exhaust line 314 may be supplied to the buffer container 61 as reflux gas to improve the neon recovery rate. Alternatively, all of the gas discharged from the moisture removal unit 66 through the exhaust line 314 may be discharged outside the neon purification apparatus 300 system.

[0051] As shown in Figure 2, the neon purification apparatus 300 includes a cold box 80. Some of the elements constituting the neon purification apparatus 300 are located inside the cold box 80. The inside of the cold box 80 is cooled by a circulating refrigerant supplied from a cryogenic refrigerator 81 to the first heat exchanger 67 and the second heat exchanger 72 inside the cold box 80. Therefore, the elements located inside the cold box 80 are maintained at a lower temperature than the elements located outside the cold box 80. Specifically, in the neon purification apparatus 300 of this embodiment, the first heat exchanger 67, preliminary separation unit 68, expansion valve 69, gas-liquid separator 70, nitrogen removal unit 71, second heat exchanger 72, helium removal unit 73, expansion valve 75, distillation column 76, and reboiler 77 are arranged inside the cold box 80 and are maintained at a lower temperature than the buffer container 61, compressor 62, hydrogen oxidation unit 63, cooler 64, ambient temperature gas-liquid separator 65, and moisture removal unit 66, which are not located inside the cold box 80.

[0052] The raw material gas from which moisture and carbon dioxide have been removed by the moisture removal unit 66 is introduced into the first heat exchanger 67 in the cold box 80. The raw material gas is introduced into the first heat exchanger 67 as a warm fluid and is cooled by the first heat exchanger 67 to a temperature between 44K and 100K, for example. The neon purification apparatus 300 of this embodiment is equipped with a cryogenic refrigerator 81. The first heat exchanger 67 is supplied with a circulating refrigerant from the cryogenic refrigerator 81. The cryogenic refrigerator 81 may, but is not limited to, a Brayton cycle. As the circulating refrigerant, for example, helium, neon, hydrogen, or a mixture of several of these can be used.

[0053] The raw material gas cooled in the first heat exchanger 67 is introduced into the preliminary separation unit 68. In the preliminary separation unit 68, nitrogen is separated and removed from the raw material gas. Specifically, the preliminary separation unit 68 in this embodiment is a device that separates nitrogen to the liquid phase and neon to the gas phase. The neon purification apparatus 300 in this embodiment also includes a reflux line 302 that allows the liquid phase components separated and removed from the raw material gas in the preliminary separation unit 68 to be introduced into a buffer container 61. The reflux line 302 is a line that connects the preliminary separation unit 68 and the buffer container 61. The reflux line 302 in this embodiment is provided with an expansion valve 69 and a gas-liquid separator 70. The liquid phase components separated and removed in the preliminary separation unit 68 are sent to the expansion valve 69, depressurized by Joule-Thomson expansion, and introduced into the gas-liquid separator 70. In the gas-liquid separator 70, nitrogen is separated to the liquid phase, and neon and helium are separated to the gas phase. The components separated into the liquid phase in the gas-liquid separator 70 are introduced as a cold fluid into the first heat exchanger 67, where they vaporize and are exhausted outside the neon purification system 300. The components separated into the gas phase in the gas-liquid separator 70 are supplied to the buffer container 61 through the reflux line 302. This improves the neon recovery rate.

[0054] The raw material gas separated to the gas phase in the preliminary separation unit 68 is introduced into the nitrogen removal unit 71. In the nitrogen removal unit 71, most of the nitrogen contained in the raw material gas is removed. Specifically, the nitrogen removal unit 71 in this embodiment is a device that removes nitrogen from the raw material gas by a TSA method that repeatedly adsorbs and regenerates due to a temperature difference. However, the nitrogen removal unit 71 may also be a VPSA method that repeatedly adsorbs and regenerates due to a pressure swing, or a PSA method.

[0055] The nitrogen removal unit 71 is equipped with an adsorbent. Examples of adsorbents in the nitrogen removal unit 71 include, but are not limited to, zeolite and activated carbon. The nitrogen removal unit 71 in this embodiment is equipped with at least two adsorption towers. Each of these at least two adsorption towers is filled with the above-mentioned adsorbent. During operation of the neon purification apparatus 300, an adsorption process is performed in at least one adsorption tower to remove nitrogen from the raw gas, and a regeneration process is performed in another at least one adsorption tower to desorb the nitrogen adsorbed on the adsorbent. This adsorption process and regeneration process are performed by switching between the at least two adsorption towers of the nitrogen removal unit 71.

[0056] In the regeneration process of the nitrogen removal unit 71, a rinse gas is supplied to the nitrogen removal unit 71 to promote the desorption of nitrogen from the adsorbent. This rinse gas may be supplied to the nitrogen removal unit 71 in a heated state by an external heater or the like. The gas used as the rinse gas is preferably a gas that does not contain nitrogen, and in this embodiment, a portion of the raw material gas from which most of the nitrogen has been removed by the nitrogen removal unit 71 is used. Specifically, a portion of the raw material gas from which most of the nitrogen has been removed by the nitrogen removal unit 71 is supplied to the nitrogen removal unit 71 as a rinse gas through a rinse gas supply line 305 that branches off from a connection line 351 connecting the nitrogen removal unit 71 and the second heat exchanger 72, which will be described later.

[0057] As described above, the desorbed gases such as nitrogen removed from the adsorbent in the nitrogen removal section 71 during the regeneration process are mixed with rinse gas supplied to the nitrogen removal section 71 and discharged from the nitrogen removal section 71 as a mixed gas. The mixed gas may also contain blowdown gas released from the adsorption tower during the depressurization process. At least a portion of the mixed gas may be supplied to the moisture removal section 66 as regenerated gas through the mixed gas supply line 310. If only a portion of the mixed gas is supplied to the moisture removal section 66 through the mixed gas supply line 310, the remainder of the mixed gas is discharged from the nitrogen removal section 71 through the exhaust line 316 branching off from the mixed gas supply line 310. If the mixed gas is not supplied to the moisture removal section 66, all of the mixed gas is discharged from the nitrogen removal section 71 through the exhaust line 316 branching off from the mixed gas supply line 310. At least a portion of the mixed gas discharged from the nitrogen removal section 71 through the exhaust line 316 may be supplied to the buffer container 61 as reflux gas to improve the neon recovery rate. Furthermore, the mixed gas discharged from the nitrogen removal unit 71 through the exhaust line 316 may all be discharged outside the neon purification unit 300 system.

[0058] The raw material gas, from which most of the nitrogen has been removed by the nitrogen removal unit 71, is introduced into the second heat exchanger 72. The raw material gas is introduced into the second heat exchanger 72 as a warm fluid and is cooled by the second heat exchanger 72 to a temperature between, for example, 25K and 44K. The second heat exchanger 72 is supplied with circulating refrigerant from the cryogenic refrigerator 81 via the first heat exchanger 67. In Figure 2, the circulating refrigerant of the cryogenic refrigerator 81 is shown circulating through the first heat exchanger 67 and the second heat exchanger 72, which are connected in series with the cryogenic refrigerator 81. However, the circulating refrigerant of the cryogenic refrigerator 81 may also circulate through the first heat exchanger 67 and the second heat exchanger 72, which are connected in parallel with the cryogenic refrigerator 81. In addition, separate refrigerators may be provided for the first heat exchanger 67 and the second heat exchanger 72, respectively.

[0059] The raw material gas cooled in the second heat exchanger 72 is introduced into the helium removal section 73. The helium removal section 73 removes helium from the raw material gas. Specifically, the helium removal section 73 in this embodiment is a low-temperature gas-liquid separator that separates the raw material gas into a separation liquid mainly composed of neon and a separation gas mainly composed of helium. At least a portion of the separation gas separated from the raw material gas in the helium removal section 73 may be supplied to the moisture removal section 66 as regenerated gas through the separation gas supply line 303. If only a portion of the separation gas is supplied to the moisture removal section 66 through the separation gas supply line 303, the remainder of the separation gas is discharged from the helium removal section 73 through the exhaust line 306 branching off from the separation gas supply line 303. Also, if the separation gas is not supplied to the moisture removal section 66, the separation gas is discharged from the helium removal section 73 through the exhaust line 306 branching off from the separation gas supply line 303. At least a portion of the separated gas discharged from the helium removal unit 73 through the exhaust line 306 may be supplied to the buffer container 61 as reflux gas to improve the neon recovery rate. Alternatively, all of the mixed gas discharged from the helium removal unit 73 through the exhaust line 306 may be discharged outside the neon purification unit 300 system.

[0060] The separation liquid, mainly composed of neon, separated in the helium removal section 73, is introduced into the expansion valve 75. This separation liquid is depressurized by Joule-Thomson expansion by the expansion valve 75 and then introduced into the top of the distillation column 76. In the distillation column 76, helium is further removed from the raw material gas, i.e., the separation liquid, from which the separation gas mainly composed of helium has been separated in the helium removal section 73. Specifically, when the raw material gas is supplied to the distillation column 76, neon gas containing helium is concentrated at the top of the column, and high-purity neon of 99 vol% or more is concentrated at the bottom of the column. This high-purity neon is extracted from the bottom of the distillation column 76 and compressed by a compressor 78 to be extracted as product neon. If the product neon is to be extracted as a liquid from the distillation column 76, a liquid transfer pump may be used instead of the compressor 78. Alternatively, the product neon may be extracted without using the compressor 78. The distillation column 76 is equipped with a reboiler 77 that vaporizes the descending liquid to produce rising gas. The distillation column 76 may be a regularly packed column, a randomly packed column, or a tray column. The heating method for the reboiler 77 may include, but is not limited to, a heating method using an electric heater or a heating method using another hot fluid via a heat exchanger. Although not shown in Figure 2, the distillation column 76 may be equipped with a condenser that cools the rising gas to produce a falling liquid. Furthermore, the neon purification apparatus 300 of this embodiment is equipped with a distillation column gas reflux line 304 that can introduce the helium-containing distillation column gas exiting from the top of the distillation column 76 into the buffer container 61. Since this distillation column gas contains 80 vol% or more of neon, the recovery rate of neon can be improved by refluxing the distillation column gas.

[0061] Next, a neon purification method using a neon purification apparatus 300, as one embodiment of the neon purification method according to the present invention, will be described. In the neon purification method using the neon purification apparatus 300, at least one of the separated gas separated and removed from the raw material gas in the helium removal section 73, and the mixed gas obtained by mixing the rinse gas supplied to the nitrogen removal section 71 and the desorbed gas desorbed from the nitrogen removal section 71, is supplied to the moisture removal section 66. This reduces the recovery rate of neon. This method allows for the regeneration of the adsorption capacity of the moisture removal unit 66 while simultaneously suppressing the reduction in operating costs. In other words, it improves the efficiency of regenerating the adsorption capacity of the moisture removal unit 66. [Examples]

[0062] Examples using the neon purification apparatus according to the present invention are described below.

[0063] [Table 1]

[0064] <Example 1> In Example 1, neon purification was performed using the neon purification apparatus 100 shown in Figure 1. First, crude neon gas was supplied to the buffer container 1 through the crude neon gas supply line 101. The specifications of the crude neon gas are shown in Table 1.

[0065] Next, the raw material gas from buffer container 1 was introduced into compressor 2. Compressor 2 compressed the raw material gas to 30 bar. 0.1 Nm³ was added to the compressed raw material gas. 3 Oxygen gas was added at a flow rate of / h, and the oxygenated raw material gas was supplied to the hydrogen oxidation unit 3. The hydrogen oxidation unit 3 was heated by an external heater. In the hydrogen oxidation unit 3, the hydrogen and oxygen in the raw material gas were converted into water. The raw material gas discharged from the hydrogen oxidation unit 3 passed through the cooler 4 and was introduced into the ambient temperature gas-liquid separator 5, where most of the moisture was removed. The raw material gas discharged from the gas phase of the ambient temperature gas-liquid separator 5 was introduced into the moisture removal unit 6. In the moisture removal unit 6, the concentrations of moisture and carbon dioxide in the raw material gas were reduced to less than 10 vol ppb each. In this example, the moisture removal unit 6 is a two-tower TSA system, where the adsorption process is performed in one adsorption tower while the regeneration process is performed in the other adsorption tower. The adsorption and regeneration processes were alternately switched between the two adsorption towers. Zeolite was packed as the adsorbent in each adsorption tower. In the regeneration process of the moisture removal unit 6, the separated gas removed from the raw material gas in the helium removal unit 11 is heated to 200°C and 1.5 Nm³ 3The separated gas was supplied to the moisture removal unit 6 via the separation gas supply line 103 at a flow rate of / h.

[0066] Next, the raw material gas from which moisture had been removed in the moisture removal section 6 was introduced into the nitrogen removal section 7. The nitrogen concentration in this raw material gas was 25 vol%. This nitrogen concentration is lower than that of the crude neon gas shown in Table 1 because the distillation column gas separated and removed from the raw material gas in the distillation column 13 was refluxed through the distillation column gas reflux line 107.

[0067] The nitrogen removal section 7 is a four-column VPSA system. While the adsorption process was being performed in one adsorption column, a regeneration process was being performed in another adsorption column, and a pressure equalization process was being performed in the remaining two adsorption columns (although only two columns are shown in Figure 1, four columns are used in Example 1). Zeolite was packed as the adsorbent in each adsorption column. In this example, the pressure in the adsorption columns was reduced to 10 bar by two pressure equalization processes, followed by depressurization, and then the system was evacuated to 0.05 bar in a vacuum evacuation process. The gas discharged in the depressurization and vacuum evacuation processes was released outside the neon purification system 100. In the exhaust gas regeneration process, a portion of the raw material gas from which most of the nitrogen has been removed in the nitrogen removal section 7 is used as a rinse gas, at a rate of 0.4 Nm³. 3 The rinse gas supplied to the nitrogen removal unit 7 was supplied at a flow rate of / h. The mixed gas, which consisted of the rinse gas supplied to the nitrogen removal unit 7 and the desorbed gas removed from the nitrogen removal unit 7, was discharged from the system via a vacuum pump.

[0068] Next, the raw material gas from which nitrogen had been removed in the nitrogen removal unit 7 was introduced into the first heat exchanger 8 in the cold box 20. The nitrogen concentration introduced into the first heat exchanger 8 was 10 vol ppm or less. In this first heat exchanger 8, the raw material gas containing neon was cooled to 68 K and introduced into the auxiliary nitrogen removal unit 9. By removing nitrogen in the auxiliary nitrogen removal unit 9, the nitrogen concentration in the raw material gas became less than 10 vol ppb.

[0069] Next, the raw material gas from which nitrogen had been removed in the auxiliary nitrogen removal section 9 was introduced into the second heat exchanger 10. In this second heat exchanger 10, the raw material gas containing neon and helium was cooled to 31K and introduced into the helium removal section 11. The separated gas separated into the gas phase in the helium removal section 11 contained more than 85 vol% helium. As described above, this separated gas was supplied as regenerated gas to the moisture removal section 6 through the separation gas supply line 103. The separated liquid separated into the liquid phase in the helium removal section 11 was reduced to 3 bar by the expansion valve 12 and then introduced into the top of the distillation column 13. This separated neon and helium from the raw material gas by distillation. The distillation column 13 is a packed column filled with irregular packing material. The distillation column 13 is equipped with a reboiler 14. The reboiler 14 uses an electric heater. Since the top gas of the distillation column 13 contains neon, it was refluxed to the buffer container 1 through the distillation column gas reflux line 107. Neon was concentrated at the bottom of the distillation column 13. The neon concentrated at the bottom of the distillation column 13 was extracted as product neon by a compressor 15. The product neon had a neon concentration of 99.99 vol% or higher, and its flow rate was 3.7 Nm³. 3 It was / h.

[0070] The neon purification apparatus 100 is equipped with a cryogenic refrigerator 21 as a cold source. The cryogenic refrigerator 21 supplied refrigerant to the first heat exchanger 8 and the second heat exchanger 10. The cryogenic refrigerator 21 employs a Brayton cycle, and a turbo compressor is used as the circulating compressor for circulating the refrigerant. Helium gas was used as the refrigerant. In this embodiment, the cryogenic refrigerator 21 required 23 kW of operating power.

[0071] As described above, in Example 1, by supplying the separated gas removed from the raw material gas in the helium removal unit 11 as a regenerated gas to the moisture removal unit 6, the adsorption capacity of the moisture removal unit 6 could be regenerated without having to prepare a separate dry gas for the regenerated gas in addition to the crude neon gas.

[0072] <Example 2> In Example 2, neon purification was performed using the neon purification apparatus 100 shown in Figure 1, similar to Example 1. Example 2 differs from Example 1 in that, instead of using the separated gas removed from the raw material gas in the helium removal section as the regeneration gas to regenerate the adsorption capacity of the moisture removal section, a mixed gas consisting of the rinse gas supplied to the nitrogen removal section and the desorbed gas removed from the nitrogen removal section was used. Other conditions and procedures are the same. Therefore, this section will mainly describe the differences from Example 1.

[0073] In Example 2, during the regeneration process of the moisture removal unit 6, a portion of the mixed gas, which is a mixture of rinse gas supplied to the nitrogen removal unit 7 and desorbed gas removed from the nitrogen removal unit 7, was compressed to 2 bar, heated to 200°C, and then supplied to the moisture removal unit 6 as regenerated gas through the mixed gas supply line 110. The average flow rate of the mixed gas supplied to the moisture removal unit 6 as regenerated gas was 1.5 Nm³. 3 The value was / h. Of the mixed gas discharged from the nitrogen removal unit 7, the remaining portion that was not used as regenerated gas was released outside the neon purification unit 100 system.

[0074] As described above, in Example 2, by supplying a mixed gas, which is a mixture of the rinse gas supplied to the nitrogen removal unit 7 and the desorbed gas removed from the nitrogen removal unit 7, to the moisture removal unit 6 as a regenerated gas, the adsorption capacity of the moisture removal unit 6 could be regenerated without having to prepare a separate dry gas for the regenerated gas from the crude neon gas.

[0075] The neon purification apparatus and neon purification method according to the present invention are not limited to the specific configurations and processes shown in the embodiments and examples described above, and various modifications, changes, substitutions, and combinations are possible as long as they do not depart from the scope of the claims. [Industrial applicability]

[0076] The present invention relates to a neon purification apparatus and a neon purification method. [Explanation of symbols]

[0077] <First Embodiment> 1: Buffer container 2: Compressor 3: Hydrogen oxidation section 4:Cooler 5: Room temperature gas-liquid separator 6: Moisture removal section 7: Nitrogen removal section 8: 1st heat exchanger 9: Auxiliary nitrogen removal unit 10:Second heat exchanger 11: Helium removal section 12: Expansion valve 13: Distillation column 14: Reboiler 15: Compressor 20: Cold Box 21: Cryogenic refrigerator 100: Neon purification device 101: Crude neon gas supply line 103: Separation gas supply line 104: Exhaust line 105: Rinse gas supply line 106: Exhaust line 107: Distillation column gas reflux line 110: Mixed gas supply line 150: Connection line 151: Connection line 152: Exhaust line <Second Embodiment> 61: Buffer container 62: Compressor 63: Hydrogen oxidation section 64:Cooler 65: Room temperature gas-liquid separator 66: Moisture removal section 67: 1st heat exchanger 68: Auxiliary separation unit 69: Expansion valve 70: Gas-liquid separator 71: Nitrogen removal section 72:Second heat exchanger 73: Helium removal section 75: Expansion valve 76: Distillation column 77: Reboiler 78: Compressor 80: Cold Box 81: Cryogenic refrigerator 300: Neon Refining Equipment 301: Crude neon gas supply line 302: Recirculation Line 303: Separation gas supply line 304: Distillation column gas reflux line 305: Rinse gas supply line 306: Exhaust line 310: Mixed gas supply line 314: Exhaust line 316: Exhaust line 350: Connection line 351: Connection line

Claims

1. A hydrogen oxidation unit that oxidizes hydrogen in a raw material gas containing neon, helium, nitrogen, and hydrogen, A moisture removal unit that adsorbs and removes moisture generated in the hydrogen oxidation unit from the raw material gas, A nitrogen removal unit that adsorbs and removes nitrogen from the raw material gas from which moisture has been adsorbed and removed in the moisture removal unit, A helium removal unit separates and removes helium from the raw material gas from which nitrogen has been adsorbed and removed in the nitrogen removal unit, A neon purification apparatus comprising at least one of the following: a separation gas supply line capable of supplying the separation gas separated and removed from the raw material gas in the helium removal section to the moisture removal section; and a mixed gas supply line capable of supplying the moisture removal section with a mixed gas, which is a mixture of the rinse gas supplied to the nitrogen removal section and the desorbed gas removed from the nitrogen removal section.

2. The neon purification apparatus according to claim 1, further comprising the separation gas supply line.

3. The neon purification apparatus according to claim 1 or 2, comprising the mixed gas supply line.

4. A neon purification method using a neon purification apparatus, The neon purification apparatus is A hydrogen oxidation unit that oxidizes hydrogen in a raw material gas containing neon, helium, nitrogen, and hydrogen, A moisture removal unit that adsorbs and removes moisture generated in the hydrogen oxidation unit from the raw material gas, A nitrogen removal unit that adsorbs and removes nitrogen from the raw material gas from which moisture has been adsorbed and removed in the moisture removal unit, The system includes a helium removal unit that separates and removes helium from the raw material gas from which nitrogen has been adsorbed and removed in the nitrogen removal unit, A neon purification method comprising supplying at least one of the separated gas removed from the raw material gas in the helium removal section and the mixed gas obtained by mixing the rinse gas supplied to the nitrogen removal section and the desorbed gas removed from the nitrogen removal section to the moisture removal section.

5. The neon purification method according to claim 4, wherein the separated gas is supplied to the moisture removal unit.

6. The neon purification method according to claim 4 or 5, wherein the mixed gas is supplied to the moisture removal unit.

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