Safe recovery assembly for high-purity liquid oxygen in krypton-xenon gas production

Abstract

The invention provides a safe recovery assembly for high-purity liquid oxygen in krypton-xenon gas production, and relates to the field of air separation. The safe recovery assembly for high-purity liquid oxygen in krypton-xenon gas production comprises a first-stage concentration tower, a second-stage concentration tower and a recovery tank, the second-stage concentration tower is arranged on one side of the first-stage concentration tower, a first circulating pipe is fixedly connected between the first-stage concentration tower and the second-stage concentration tower, and a second circulating pipe is fixedly connected between the first-stage concentration tower and the second-stage concentration tower. The top end of the second-stage concentration tower and the bottom end of the rear side of the first-stage concentration tower are fixedly connected with return pipes, the interiors of the first-stage concentration tower and the second-stage concentration tower are fixedly connected with reinforcing inner frames, and the interiors of the reinforcing inner frames are provided with low-temperature-resistant stainless steel liners. The detachable structure is arranged at the top of the concentration tower, later maintenance, overhaul and cleaning operation can be facilitated, the use safety is improved by arranging the reinforcing inner frame and the low-temperature-resistant stainless steel inner container in the concentration tower, and the safety protection effect on equipment is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of air separation, in particular to a safe recovery component for high-purity liquid oxygen in krypton-xenon gas production. Background Art

[0002] Krypton and xenon are rare gases found in air. Their properties have led to their widespread use in various industries, including electronic chip manufacturing, healthcare, and basic scientific research. Currently, my country primarily extracts krypton and xenon from byproducts of air separation plants (ASUs). At atmospheric pressure, the boiling points of krypton and xenon are 119K and 165K, respectively, both higher than the boiling point of oxygen. Therefore, in ASUs, krypton and xenon are primarily present in liquid oxygen and are typically discharged with the product oxygen or liquid oxygen. Extracting krypton and xenon from air involves first obtaining krypton-xenon-depleted liquid oxygen from the ASU. The krypton and xenon contained in the liquid oxygen are then further concentrated to produce a krypton-xenon mixture. Finally, this mixture is further separated and refined to produce pure krypton and xenon, respectively. However, during the purification process of the oxygen-depleted liquid oxygen, some of the separated oxygen cannot be effectively recovered, resulting in a waste of resources.

[0003] Krypton and xenon in existing technologies are rare gases in the air, but in the field of electronic chip manufacturing, liquid oxygen needs to be extracted under normal pressure. Traditional extraction methods include: cryogenic distillation, adsorption, catalytic reaction combined process, etc. However, traditional methods are not safe to use, resulting in increased pressure resistance and leakage risk after a certain number of years of use. At the same time, the equipment is expensive and inconvenient to operate. Summary of the Invention

[0004] (1) Technical problems solved

[0005] In response to the shortcomings of the existing technology, the present invention provides a safe recovery component for high-purity liquid oxygen in krypton-xenon gas production, which solves the problems of low safety in traditional methods, resulting in increased pressure resistance and leakage risk after a certain number of years of use of the equipment, high equipment costs, and inconvenience in operation and use.

[0006] (2) Technical solution

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions: A safe recovery assembly for high-purity liquid oxygen in krypton-xenon gas production, comprising: a primary concentrator, a secondary concentrator, and a recovery tank, wherein a secondary concentrator is provided on one side of the primary concentrator, a first flow pipe is fixedly connected between the primary and secondary concentrators, a reflux pipe is fixedly connected to the top of the secondary concentrator and the rear bottom end of the primary concentrator, a reinforced inner frame is fixedly connected to the interior of each of the primary and secondary concentrators, a low-temperature-resistant stainless steel liner is provided inside the reinforced inner frame, a detachable top cover is covered on the top of each of the primary and secondary concentrators, a fastening bolt is threadedly connected to the detachable top cover and the interior of the primary and secondary concentrators, a second flow pipe is fixedly connected to the rear bottom end of the secondary concentrator, a pump body is flanged in the middle between the first flow pipe, the reflux pipe, and the second flow pipe, and a limiting ring is fixedly connected to the interior of each of the first flow pipe, the reflux pipe, and the second flow pipe.

[0008] Preferably, one end of the second circulation pipe away from the secondary concentrator is fixedly connected to a recovery tank, and a booster pump is fixedly connected to the upper side walls of the primary concentrator, the secondary concentrator and the recovery tank.

[0009] Preferably, a filling layer is provided above the center of the first-stage concentrating tower and the second-stage concentrating tower, and a condensation zone is provided between the top of the filling layer and the concentrating tower.

[0010] Preferably, a water bath vaporizer is fixedly connected to one side of the recovery tank.

[0011] Preferably, an exhaust pipe is fixedly connected to the top of the first-level concentrating tower, and sealing rings are filled between the disassembly top cover and the first-level concentrating tower and the second-level concentrating tower.

[0012] Preferably, a reboiler is fixedly connected to the bottom end of one side of the primary concentrator and the secondary concentrator.

[0013] A safe recovery method for high-purity liquid oxygen in krypton-xenon gas production, comprising the following specific recovery methods:

[0014] Step 1: Raw material pretreatment

[0015] The krypton-xenon-containing liquid oxygen feedstock is transported to the first-stage enrichment tower, ensuring that the feedstock temperature is maintained below -183°C to maintain its liquid state. The first and second-stage enrichment towers are equipped with low-temperature-resistant stainless steel liners, and each flow pipe is equipped with reinforced inner tubes to prevent gas leakage and provide pressure resistance, increasing equipment safety protection and ensuring safe and efficient production.

[0016] Step 2: Primary distillation and concentration

[0017] In the first-stage concentrator, a booster pump pressurizes the interior of the first-stage concentrator to 5-25 bar. The reboiler heats the liquid oxygen, partially evaporating it. As the vapor rises through the packing layer inside the first-stage concentrator, krypton and xenon, which have higher boiling points, are concentrated in the condensation zone, while liquid oxygen, with a lower boiling point, flows back downward, resulting in a mixed liquid with a high krypton and xenon concentration at the bottom of the first-stage concentrator.

[0018] Step 3: Secondary distillation purification

[0019] The liquid at the bottom of the first concentrator is pressurized by a pump and circulated to the second concentrator, where it is heated by a reboiler to further separate the residual oxygen. The gas at the top of the tower will return to the middle of the first concentrator through a reflux pipe, and the bottom of the tower will produce a concentrated liquid with a krypton and xenon content of more than 90%;

[0020] Step 4: Hyperbaric oxygen recovery:

[0021] The liquid at the bottom of the secondary tower is circulated to the inside of the recovery tank and pressurized to 30-50 bar by a booster pump. It is heated to room temperature by a water bath vaporizer and converted into high-pressure gaseous oxygen. The gas is reduced in pressure by a throttle valve and then enters the regenerator to exchange heat with the raw liquid oxygen to recover cold energy, thus completing the efficient separation of oxygen and krypton and xenon.

[0022] Preferably, the reboiler heating temperature in step 2 is: -170°C-160°C, and the reboiler heating temperature in step 3 is: -160°C-150°C.

[0023] (3) Beneficial effects

[0024] The present invention provides a safe recovery assembly for high-purity liquid oxygen in krypton-xenon gas production. It has the following beneficial effects:

[0025] 1. The present invention is provided with: a first-level concentration tower, a reinforced inner frame, a low-temperature resistant stainless steel inner liner and a detachable top cover. By arranging a disassembly structure on the top of the concentration tower, it can facilitate subsequent maintenance, inspection and cleaning operations. In addition, the arrangement of the reinforced inner frame and the low-temperature resistant stainless steel inner liner inside the concentration tower increases the safety of use and provides a safety protection effect for the equipment. By tightening the bolts, high-strength sealing is ensured while achieving leakage prevention, pressure resistance and explosion prevention.

[0026] 2. The present invention is equipped with: a booster pump, a water bath vaporizer and a recovery tank. The liquid at the bottom of the secondary tower is circulated to the interior of the recovery tank and pressurized to 30-50 bar by the booster pump. It is heated to room temperature by the water bath vaporizer and converted into high-pressure gaseous oxygen. The gas is reduced in pressure by a throttle valve and then enters the regenerator to exchange heat with the raw liquid oxygen to recover cold energy. The oxygen and krypton-xenon are efficiently separated. The separation of krypton-xenon gas and liquid oxygen through this structure improves portability, low cost and easy operation.

[0027] 3. The present invention is provided with: a reinforced inner tube, a limiting ring and a first flow tube. The limiting rings are respectively provided inside the first flow tube. The reinforcing inner tube is fixed by the limiting rings, thereby increasing the use strength of the first flow tube, making it less likely to have the risk of leakage and explosion caused by high pressure, thereby improving the safety and stability of use. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a three-dimensional structural diagram of a safe recovery assembly for high-purity liquid oxygen in krypton-xenon gas production proposed by the present invention;

[0029] Figure 2 This is a rear perspective structural diagram of a safety recovery assembly for high-purity liquid oxygen in krypton-xenon gas production proposed by the present invention;

[0030] Figure 3 This is a structural diagram of the first-stage concentration tower and the disassembled top cover of a safe recovery assembly for high-purity liquid oxygen in krypton-xenon gas production proposed by the present invention;

[0031] Figure 4 This is a cross-sectional elevation view of a safe recovery assembly for high-purity liquid oxygen in krypton-xenon gas production proposed by the present invention;

[0032] Figure 5 This is a front view of the cross section of the first flow pipe of a safety recovery assembly for high-purity liquid oxygen in krypton-xenon gas production proposed by the present invention.

[0033] Among them, 1. First-stage concentration tower; 101. First circulation pipe; 1011. Pump body; 1012. Reinforced inner pipe; 1013. Limiting ring; 102. Exhaust pipe; 2. Second-stage concentration tower; 201. Reboiler; 202. Booster pump; 3. Second circulation pipe; 4. Reflux pipe; 5. Recovery tank; 501. Water bath vaporizer; 6. Reinforced inner frame; 601. Low-temperature resistant stainless steel inner liner; 602. Sealing ring; 603. Disassemble the top cover; 604. Tighten the bolts; 7. Filling layer; 8. Condensation area. DETAILED DESCRIPTION

[0034] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0035] Example 1:

[0036] like Figure 1-5As shown, an embodiment of the present invention provides a safe recovery component for high-purity liquid oxygen in krypton-xenon gas production, comprising a primary concentrator 1, a secondary concentrator 2 and a recovery tank 5, characterized in that: a secondary concentrator 2 is provided on one side of the primary concentrator 1, a first flow pipe 101 is fixedly connected between the primary concentrator 1 and the secondary concentrator 2, a reflux pipe 4 is fixedly connected to the top of the secondary concentrator 2 and the rear bottom end of the primary concentrator 1, and a gas reflux effect can be achieved through the reflux pipe 4, the interior of the primary concentrator 1 and the secondary concentrator 2 are both fixedly connected with a reinforced inner frame 6, the use strength is increased by the reinforced inner frame 6, a low-temperature resistant stainless steel inner liner 601 is provided inside the reinforced inner frame 6, the interior of the enrichment tower is provided with the reinforced inner frame 6 and the low-temperature resistant stainless steel inner liner 601, the use safety is increased by the arrangement of the reinforced inner frame 6 and the low-temperature resistant stainless steel inner liner 601, the safety of use is increased, and the equipment has a safety protection effect, the top of the primary concentrator 1 and the secondary concentrator 2 are both covered with a detachable top cover 603, and a detachable top cover 603 structure is provided at the top of the enrichment tower. It can facilitate later maintenance, inspection and cleaning operations. The top cover 603 and the internal threaded connection of the first-level concentration tower 1 and the second-level concentration tower 2 are connected with fastening bolts 604. The fastening bolts 604 ensure high-strength sealing while also achieving leakage, pressure resistance and explosion-proof effects. The rear bottom end of the second-level concentration tower 2 is fixedly connected with the second flow pipe 3. The middle parts between the first flow pipe 101, the return pipe 4 and the second flow pipe 3 are flange-connected with a pump body 1011. The pressure circulation is enhanced by the pump body 1011. The internal ends of the first flow pipe 101, the return pipe 4 and the second flow pipe 3 are fixedly connected with limiting rings 1013. Limiting rings 1013 are respectively arranged inside the first flow pipe 101. The fixing of the reinforcing inner tube 1012 by the limiting ring 1013 increases the use strength of the first flow pipe 101, and is less likely to cause leakage and explosion risks due to high pressure, thereby improving the safety and stability of use. The reinforcing inner tube 1012 is fixedly connected to the internal of the limiting ring 1013.

[0037] The end of the second circulation pipe 3 away from the secondary concentration tower 2 is fixedly connected to the recovery tank 5, and the purified gas is circulated through the recovery tank 5 to complete the final separation work. The upper part of the outer wall of the primary concentration tower 1, the secondary concentration tower 2 and the recovery tank 5 is fixedly connected with a booster pump 202. Through the setting of the booster pump 202, the gas pressure inside the primary concentration tower 1, the secondary concentration tower 2 and the recovery tank 5 can be set and controlled. A filling layer 7 is set above the middle of the interior of the primary concentration tower 1 and the secondary concentration tower 2. Above the filling layer 7 A condensation zone 8 is provided between the first-stage concentrator 1 and the concentration tower. A water bath vaporizer 501 is fixedly connected to one side of the recovery tank 5. The gas is heated to room temperature by the water bath vaporizer 501 and converted into high-pressure gaseous oxygen. The gas enters the regenerator after being depressurized by the throttle valve, and exchanges heat with the raw liquid oxygen to recover cold energy. An exhaust pipe 102 is fixedly connected to the top of the first-stage concentrator 1. A sealing ring 602 is filled between the removable top cover 603 and the first-stage concentrator 1 and the second-stage concentrator 2. A reboiler 201 is fixedly connected to the bottom end of one side of the first-stage concentrator 1 and the second-stage concentrator 2.

[0038] Example 2:

[0039] This embodiment differs from the first embodiment in that: a safe recovery method for high-purity liquid oxygen in krypton-xenon gas production includes the following specific recovery methods:

[0040] Step 1: Raw material pretreatment

[0041] The krypton-xenon-containing liquid oxygen raw material is transported to the first-stage enrichment tower, and the raw material temperature is maintained below -183°C to maintain the liquid state. The first and second-stage enrichment towers 1 and 2 are equipped with low-temperature resistant stainless steel inner tanks 601, and each flow pipe is equipped with a reinforced inner tube 1012 to prevent gas leakage and pressure resistance, increase equipment safety protection, and ensure safe and efficient production.

[0042] Step 2: Primary distillation and concentration

[0043] In the primary concentrator 1, a booster pump 202 pressurizes the interior of the primary concentrator 1 to a pressure of 5-25 bar. The liquid oxygen is partially evaporated by heating in a reboiler 201 at a temperature of -170°C to 160°C. As the vapor rises through the packing layer 7 inside the primary concentrator 1, krypton and xenon, which have higher boiling points, are concentrated in the condensation zone 8, while liquid oxygen, which has a lower boiling point, refluxes downward, resulting in a mixed liquid with an increased krypton and xenon concentration at the bottom of the primary concentrator 1.

[0044] Step 3: Secondary distillation purification

[0045] The liquid at the bottom of the primary concentrator 1 is pressurized by pump 1011 and circulated to the secondary concentrator 2. It is then heated by reboiler 201 at a temperature of -160°C to 150°C to further separate the residual oxygen. The gas at the top of the tower is returned to the middle of the primary concentrator 1 through reflux pipe 4, producing a concentrated liquid with a krypton-xenon content greater than 90% at the bottom of the tower.

[0046] Step 4: Hyperbaric oxygen recovery:

[0047] The liquid at the bottom of the secondary tower is circulated into the interior of the recovery tank 5 and pressurized to 30-50 bar by the booster pump 202. It is then heated to room temperature by the water bath vaporizer 501 and converted into high-pressure gaseous oxygen. The gas is depressurized by the throttle valve and then enters the regenerator, where it exchanges heat with the raw liquid oxygen to recover cold energy, thus completing the efficient separation of oxygen from krypton and xenon.

[0048] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A safe recovery assembly for high-purity liquid oxygen in krypton-xenon gas production, comprising a primary concentration tower (1), a secondary concentration tower (2) and a recovery tank (5), characterized in that: A secondary concentrating tower (2) is provided on one side of the primary concentrating tower (1), a first circulation pipe (101) is fixedly connected between the primary concentrating tower (1) and the secondary concentrating tower (2), a reflux pipe (4) is fixedly connected to the top of the secondary concentrating tower (2) and the rear bottom of the primary concentrating tower (1), a reinforced inner frame (6) is fixedly connected to the interior of the primary concentrating tower (1) and the secondary concentrating tower (2), a low-temperature resistant stainless steel inner liner (601) is provided inside the reinforced inner frame (6), and a detachable top cover (603) is covered on the top of the primary concentrating tower (1) and the secondary concentrating tower (2). The disassembly top cover (603) and the internal threads of the first concentration tower (1) and the second concentration tower (2) are connected with fastening bolts (604); the rear bottom end of the second concentration tower (2) is fixedly connected with a second circulation pipe (3); the middle parts between the first circulation pipe (101), the return pipe (4) and the second circulation pipe (3) are flange-connected with a pump body (1011); the internal ends of the first circulation pipe (101), the return pipe (4) and the second circulation pipe (3) are fixedly connected with limiting rings (1013); the interior of the limiting ring (1013) is fixedly connected with a reinforcing inner pipe (1012).

2. The safe recovery assembly for high-purity liquid oxygen in krypton-xenon gas production according to claim 1, characterized in that: The end of the second circulation pipe (3) away from the secondary concentration tower (2) is fixedly connected to a recovery tank (5), and the upper sides of the outer walls of the primary concentration tower (1), the secondary concentration tower (2) and the recovery tank (5) are all fixedly connected to a booster pump (202).

3. The safe recovery assembly for high-purity liquid oxygen in krypton-xenon gas production according to claim 1, characterized in that: A filling layer (7) is provided above the center of the first-stage concentration tower (1) and the second-stage concentration tower (2), and a condensation zone (8) is provided above the filling layer (7) and between the concentration towers.

4. The safe recovery assembly for high-purity liquid oxygen in krypton-xenon gas production according to claim 2, characterized in that: A water bath vaporizer (501) is fixedly connected to one side of the recovery tank (5).

5. The safe recovery assembly for high-purity liquid oxygen in krypton-xenon gas production according to claim 1, characterized in that: The top of the primary concentration tower (1) is fixedly connected to an exhaust pipe (102), and a sealing ring (602) is filled between the disassembly top cover (603) and the primary concentration tower (1) and the secondary concentration tower (2).

6. The safe recovery assembly for high-purity liquid oxygen in krypton-xenon gas production according to claim 1, characterized in that: A reboiler (201) is fixedly connected to the bottom end of one side of the primary concentration tower (1) and the secondary concentration tower (2).

7. A method for safely recovering high-purity liquid oxygen in krypton-xenon gas production, based on the safe recovery assembly for high-purity liquid oxygen in krypton-xenon gas production according to any one of claims 1 to 6, characterized in that: The following specific recycling methods are included: Step 1: Raw material pretreatment The krypton-xenon-containing liquid oxygen raw material is transported to the first-stage concentration tower, and the raw material temperature is maintained below -183°C to maintain the liquid state. A low-temperature resistant stainless steel liner (601) is provided inside the first concentration tower (1) and the second-stage concentration tower (2), and a reinforced inner tube (1012) is provided inside each flow pipe to prevent gas leakage and pressure resistance, thereby increasing equipment safety protection and ensuring safe and efficient production. Step 2: Primary distillation and concentration In the first-stage concentrator (1), a booster pump (202) pressurizes the interior of the first-stage concentrator (1) to a pressure of 5-25 bar, and heats the liquid oxygen through a reboiler to partially evaporate the liquid oxygen. When the vapor rises and passes through the internal packing layer (7) of the first-stage concentrator (1), krypton and xenon, which have a higher boiling point, are enriched in the condensation zone (8), while liquid oxygen, which has a lower boiling point, refluxes downward, and a mixed liquid with an increased krypton and xenon concentration is obtained at the bottom of the first-stage concentrator (1); Step 3: Secondary distillation purification The liquid at the bottom of the first concentration tower 1 is pressurized by a pump body (1011) and circulated to the second concentration tower (2), where it is heated by a reboiler (201) to further separate the residual oxygen. The gas at the top of the tower is returned to the middle of the first concentration tower (1) through a reflux pipe (4), and a concentrated liquid with a krypton and xenon content greater than 90% is produced at the bottom of the tower. Step 4: Hyperbaric oxygen recovery: The liquid at the bottom of the secondary tower is circulated to the interior of the recovery tank (5), and is pressurized to 30-50 bar by a booster pump (202), and is heated to room temperature by a water bath vaporizer (501), and converted into high-pressure gaseous oxygen; the gas is reduced in pressure by a throttle valve and enters a regenerator, where it exchanges heat with the raw liquid oxygen to recover cold energy, thereby achieving efficient separation of oxygen and krypton and xenon.

8. The method for safely recovering high-purity liquid oxygen in krypton-xenon gas production according to claim 7, characterized in that: The heating temperature of the reboiler (201) in step 2 is: -170°C-160°C, and the heating temperature of the reboiler (201) in step 3 is: -160°C-150°C.

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