Device for extracting high-purity liquid oxygen from low-temperature rectified liquid oxygen

Abstract

The utility model relates to the field of low-temperature rectification oxygen production, in particular to a device for extracting high-purity liquid oxygen from low-temperature rectification liquid oxygen, which comprises a rectification tower I, a main heat exchanger, a rectification tower II, a condenser I, a condenser II, a condenser III, a condenser IV and a condenser V, an extraction opening I is formed in one side of the middle part I and is communicated with an inner cavity of the lower part I through a spraying pipeline; a liquid oxygen condensation outlet of the condenser III is connected with a liquid oxygen inlet of the rectifying tower II through a liquid oxygen conveying pipeline; a high-purity liquid oxygen outlet is formed in one side of the bottom of the second lower portion of the second rectifying tower and connected with the main heat exchanger through a first oxygen conveying pipeline, high-purity liquid oxygen is conveyed to a high-purity liquid oxygen storage tank after heat exchange, and an oxygen outlet is formed in one side of the second upper portion of the second rectifying tower and connected with the main heat exchanger through a second oxygen conveying pipeline. The device is simple in structure and convenient to operate and maintain, and a high-purity oxygen product with the oxygen purity higher than 99.99988% can be obtained through multi-stage rectification treatment.

Description

Technical Field

[0001] The utility model relates to the field of cryogenic distillation oxygen production, in particular to a device for extracting high-purity liquid oxygen from cryogenic distillation liquid oxygen. Background Art

[0002] High-purity oxygen is mainly used in thermal oxidation, diffusion, chemical vapor deposition and plasma etching processes of semiconductor parts, optical fiber production, etc. It can also be used for standard gas, calibration gas, zero-point gas, etc. It has wide and important applications in modern industrial applications and scientific research.

[0003] In the prior art, air separation equipment is often used to liquefy air and then purify it through low-temperature distillation to obtain high-purity oxygen, or high-purity oxygen with a purity of more than 99.99% is produced through a catalytic reactor and a purification device. The entire equipment is large in scale and has poor independent operation, resulting in a long process for the preparation of high-purity oxygen, high energy consumption, and incomplete removal of high and low boiling point components, so that the oxygen content in the high-purity oxygen cannot reach the requirement of 99.99988%.

[0004] Therefore, there is an urgent need to design a device with low energy consumption and capable of meeting the requirements for preparing 99.99988% high-purity oxygen. Utility Model Content

[0005] The utility model aims to provide a device for extracting high-purity liquid oxygen from cryogenically distilled liquid oxygen, wherein each device can operate independently, and there is no need to set up a catalytic reaction furnace and a purification device, thereby reducing the energy consumption in the extraction process of high-purity liquid oxygen and the investment scale of the device, making the process of the entire device safer and more reliable, and the operation and maintenance of the device convenient and quick.

[0006] In order to solve the above technical problems, the utility model provides a device for extracting high-purity liquid oxygen from low-temperature rectification liquid oxygen, comprising a rectification tower 1, a main heat exchanger, a rectification tower 2, a condenser 1, a condenser 2, a condenser 3, a condenser 4 and a condenser 5, wherein the rectification tower 1 comprises a lower part 1, a middle part 1 and an upper part 1 from bottom to top, the condenser 1 is arranged in the lower part 1, the condenser 2 is arranged in the middle part 1, and the condenser 3 is arranged in the upper part 1;

[0007] A liquid oxygen inlet one is provided on one side of the upper part of the middle part one, an extraction port one is provided on one side of the middle part one and is connected to the inner cavity of the lower part one through a spray pipe, the inner cavity of the upper part one is connected to the liquid oxygen condensation inlet of the condenser three through an oxygen delivery pipe three, and the liquid oxygen condensation outlet of the condenser three is connected to the liquid oxygen inlet of the distillation tower two through a liquid oxygen delivery pipe;

[0008] The distillation tower 2 includes a lower part 2 and an upper part 2 from bottom to top, the condenser 4 is arranged in the lower part 2, and the condenser 5 is arranged in the upper part 2. A high-purity liquid oxygen outlet is provided on one side of the bottom of the lower part 2 and is connected to the main heat exchanger through an oxygen supply pipeline 1. The high-purity liquid oxygen is sent to the high-purity liquid oxygen storage tank after heat exchange. An oxygen outlet is provided on one side of the upper part 2 and is connected to the main heat exchanger through an oxygen supply pipeline 2.

[0009] Furthermore, the nitrogen inlets of the condenser one, the condenser two and the condenser four are respectively connected to the nitrogen pipeline one, the nitrogen pipeline two and the nitrogen pipeline four, the nitrogen outlets of the condenser one and the condenser two are connected to the nitrogen inlet of the condenser three through the nitrogen pipeline three, and the nitrogen outlet of the condenser four is connected to the nitrogen inlet of the condenser five through the nitrogen pipeline five.

[0010] Furthermore, the nitrogen in the nitrogen pipeline three is cooled by the main heat exchanger and then transported to the condenser three, and the nitrogen in the nitrogen pipeline five is cooled by the main heat exchanger and then transported to the condenser five.

[0011] Furthermore, a second extraction port is provided on one side of the lower portion one, and the second extraction port is connected to the inner cavity of the middle portion one through an external pipe.

[0012] Furthermore, a return pipe 1 is connected in parallel to the liquid oxygen delivery pipe, and the return pipe 1 is connected to the inner cavity of the upper part 1.

[0013] Furthermore, the oxygen supply pipeline 2 is connected to the condenser 5 through an external pipeline 2, and an extraction port 3 is opened on one side of the upper part 2, and the extraction port 3 is connected to the inner cavity of the distillation tower 2 through a reflux pipeline 2.

[0014] Furthermore, a high-boiling-point component outlet is provided at the bottom of the lower part one, and a low-boiling-point component outlet one and a low-boiling-point component outlet two are provided at the top of the upper part one and the upper part two, respectively. The low-boiling-point components at the low-boiling-point component outlet one and the low-boiling-point component outlet two recover cold through a cold recovery pipeline through the main heat exchanger.

[0015] Furthermore, the second liquid oxygen inlet of the second distillation tower is arranged in the middle of the second distillation tower.

[0016] The beneficial effects of the utility model are:

[0017] 1. The utility model has a simple structure and convenient operation and maintenance. Each device can operate independently, and there is no need to set up a catalytic reaction furnace and a purification device. The energy consumption of high-purity liquid oxygen in the extraction process and the investment scale of the device are reduced, making the process of the entire device safer and more reliable. Through the structure of the distillation tower one, the main heat exchanger, the distillation tower two, the condenser one, the condenser two, the condenser three, the condenser four and the condenser five, the liquid oxygen can be subjected to multi-stage distillation treatment to obtain a high-purity oxygen product with an oxygen purity higher than 99.99988%.

[0018] 2. The utility model further improves the purification of low-boiling point components by providing an extraction port 2 on one side of the lower part 1, and the extraction port 2 is connected to the inner cavity of the middle part 1 through an external pipe 1; combined with the design that a liquid oxygen inlet is provided on the upper side of the middle part 1, and an extraction port 1 is provided on one side of the middle part 1 and is connected to the inner cavity of the lower part 1 through a spray pipe, the high-boiling point components can be deeply purified twice, further reducing impurities in the high-purity oxygen product and improving the recovery of high and low boiling point components. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solution of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 It is a schematic diagram of a device for extracting high-purity liquid oxygen from cryogenically distilled liquid oxygen of the utility model;

[0021] In the figure: 1-distillation tower 1, 2-main heat exchanger, 3-distillation tower 2, 4-condenser 1, 5-condenser 2, 6-condenser 3, 7-condenser 4, 8-condenser 5, 9-high-purity liquid oxygen storage tank, 11-lower part 1, 12-middle part 1, 13-upper part 1, 101-liquid oxygen inlet 1, 102-extraction port 1, 103-spraying pipeline, 104-oxygen delivery pipeline 3, 105-liquid oxygen delivery pipeline, 106-reflux pipeline 1, 107-cold recovery pipeline, 301-liquid oxygen inlet 2, 31-lower part 2, 32- 2-upper part two, 302-high purity liquid oxygen outlet, 303-oxygen supply pipeline one, 304-oxygen outlet, 305-oxygen supply pipeline two, 321-extraction port three, 322-reflux pipeline two, 323-external pipeline two, 41-nitrogen pipeline one, 51-nitrogen pipeline two, 61-nitrogen pipeline three, 71-nitrogen pipeline four, 81-nitrogen pipeline five, 111-extraction port two, 112-external pipeline one, 113-high boiling point component outlet, 131-low boiling point component outlet one, 324-low boiling point component outlet two. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings of the utility model specification to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0023] In a specific embodiment of the present invention, Figure 1 As shown, a device for extracting high-purity liquid oxygen from cryogenically distilled liquid oxygen comprises a distillation tower 1, a main heat exchanger 2, a distillation tower 2 3, a condenser 1 4, a condenser 2 5, a condenser 3 6, a condenser 4 7 and a condenser 5 8. The distillation tower 1 comprises a lower part 11, a middle part 12 and an upper part 13 from bottom to top. The condenser 14 is arranged in the lower part 11, the condenser 2 5 is arranged in the middle part 12, and the condenser 3 6 is arranged in the upper part 13.

[0024] A liquid oxygen inlet 101 is provided on one side above the middle part 12, an extraction port 102 is provided on one side of the middle part 12 and is connected to the inner cavity of the lower part 11 through a spray pipe 103, the inner cavity of the upper part 13 is connected to the liquid oxygen condensation inlet of the condenser three 6 through an oxygen delivery pipe three 104, and the liquid oxygen condensation outlet of the condenser three 6 is connected to the liquid oxygen inlet two 301 of the distillation tower two 3 through a liquid oxygen delivery pipe 105; in this embodiment, the liquid oxygen inlet two 301 of the distillation tower two 3 is arranged in the middle of the distillation tower two 3;

[0025] The distillation tower 2 3 includes a lower part 2 31 and an upper part 2 32 from bottom to top, a condenser 4 7 is arranged in the lower part 2 31, and a condenser 5 8 is arranged in the upper part 2 32. A high-purity liquid oxygen outlet 302 is provided on one side of the bottom of the lower part 2 31 and is connected to the main heat exchanger 2 through an oxygen supply pipeline 1 303. The high-purity liquid oxygen is sent to the high-purity liquid oxygen storage tank 9 after heat exchange. An oxygen outlet 304 is provided on one side of the upper part 2 32 and is connected to the main heat exchanger 2 through an oxygen supply pipeline 2 305.

[0026] Specifically, in this embodiment, the nitrogen inlets of condenser one 4, condenser two 5 and condenser four 7 are respectively connected to nitrogen pipeline one 41, nitrogen pipeline two 51 and nitrogen pipeline four 71, the nitrogen outlets of condenser one 4 and condenser two 5 are connected to the nitrogen inlet of condenser three 6 through nitrogen pipeline three 61, and the nitrogen outlet of condenser four 7 is connected to the nitrogen inlet of condenser five 8 through nitrogen pipeline five 81.

[0027] Specifically, in this embodiment, the nitrogen in the nitrogen pipeline three 61 is cooled by the main heat exchanger 2 and then transported to the condenser three 6, and the nitrogen in the nitrogen pipeline five 81 is cooled by the main heat exchanger 2 and then transported to the condenser five 8. This design can simplify the layout of the cold air pipeline and improve the utilization rate of the cold air.

[0028] Specifically, in this embodiment, a second extraction port 111 is provided on one side of the lower portion 11, and the second extraction port 111 is connected to the inner cavity of the middle portion 12 through an external pipe 112. This design can further improve the purification of low-boiling-point components; a high-boiling-point component outlet 113 is provided at the bottom of the lower portion 11, which can recover the high-boiling-point components condensed and separated by the condenser 2 5 and the condenser 4;

[0029] A low boiling point component outlet 131 and a low boiling point component outlet 2 324 are respectively provided at the top of the upper part 13 and the upper part 2 32. The low boiling point components at the low boiling point component outlet 131 and the low boiling point component outlet 2 324 are recovered through the main heat exchanger 2 via the cold recovery pipe 107, thereby improving the recovery rate of cold energy.

[0030] Specifically, in this embodiment, a return pipe 106 is connected in parallel to the liquid oxygen delivery pipe 105, and the return pipe 106 is connected to the inner cavity of the upper part 13.

[0031] Specifically, in this embodiment, the oxygen supply pipeline 2 305 is connected to the condenser 5 8 through the external pipeline 2 323, and an extraction port 321 is opened on one side of the upper part 2 32, and the extraction port 321 is connected to the inner cavity of the distillation tower 2 3 through the reflux pipeline 2 322.

[0032] The main working process of this utility model is:

[0033] The raw liquid oxygen enters the distillation tower 1 from the liquid oxygen inlet 101 for distillation. The distilled oxygen enters the condenser 3 6 for condensation. After condensation into liquid, a part of it flows back into the top of the distillation tower 1 as the reflux liquid of the distillation tower 1, and the other part of the liquid oxygen enters the middle part of the distillation tower 2 3 for secondary distillation.

[0034] In the distillation tower 23, oxygen rises and is divided into two parts at the top of the distillation tower 23. One part is used as ordinary oxygen and enters the main heat exchanger 2 through the oxygen outlet 304 on one side of the upper part 232 through the oxygen delivery pipeline 2305, and is introduced into the corresponding pipeline after being heated; the other part enters the condenser 58 through the external pipeline 2323 to be condensed, and the condensed liquid is refluxed into the top of the distillation tower 23 through the reflux pipeline 2322 as its reflux liquid;

[0035] After the liquid oxygen is rectified in the distillation tower 2 3, high-purity liquid oxygen is obtained at the bottom of the distillation tower 2 3, and enters the main heat exchanger 2 through the oxygen delivery pipeline 1 303 for supercooling, and then is transported to the high-purity liquid oxygen storage tank 9 to obtain a high-purity oxygen product with an oxygen purity higher than 99.99988%;

[0036] At the top of the distillation tower 1 and the distillation tower 2 3, the gas of the low-boiling point component is continuously enriched, and when it rises to the top, it is led out through the cold recovery pipeline 107 into the main heat exchanger 2 to recover its cold, and then enters the corresponding recovery pipeline; here, the low-boiling point components mainly include nitrogen, argon, CO, H2 and other components;

[0037] Part of the liquid is extracted from the extraction port 102 through the spray pipe 103 as the spray liquid of the bottom distillation section of the distillation tower 1, and the spray liquid is condensed by the condenser 4 to obtain deep purification, wherein the high boiling point components in the liquid are gradually enriched, reaching a high value at the bottom, and are discharged and recovered through the high boiling point component outlet 113, and the high boiling point components mainly include CH4, other alkanes, krypton, xenon, CO2 and other components.

[0038] The above disclosure is only a preferred embodiment of the present invention, and certainly cannot be used to limit the scope of rights of the present invention. Therefore, equivalent changes made according to the claims of the present invention are still within the scope covered by the present invention.

Claims

1. A device for extracting high-purity liquid oxygen from cryogenically distilled liquid oxygen, characterized in that: The invention comprises a distillation tower 1 (1), a main heat exchanger (2), a distillation tower 2 (3), a condenser 1 (4), a condenser 2 (5), a condenser 3 (6), a condenser 4 (7) and a condenser 5 (8), wherein the distillation tower 1 (1) comprises, from bottom to top, a lower part 1 (11), a middle part 1 (12) and an upper part 1 (13), the condenser 1 (4) is arranged in the lower part 1 (11), the condenser 2 (5) is arranged in the middle part 1 (12), and the condenser 3 (6) is arranged in the upper part 1 (13); A liquid oxygen inlet (101) is provided on one side of the upper portion of the middle portion (12); an extraction port (102) is provided on one side of the middle portion (12) and is connected to the inner cavity of the lower portion (11) through a spray pipe (103); the inner cavity of the upper portion (13) is connected to the liquid oxygen condensation inlet of the condenser (6) through an oxygen delivery pipe (104); the liquid oxygen condensation outlet of the condenser (6) is connected to the liquid oxygen inlet (301) of the distillation tower (2) through a liquid oxygen delivery pipe (105); The distillation tower 2 (3) includes a lower part 2 (31) and an upper part 2 (32) from bottom to top, the condenser 4 (7) is arranged in the lower part 2 (31), and the condenser 5 (8) is arranged in the upper part 2 (32). A high-purity liquid oxygen outlet (302) is provided on one side of the bottom of the lower part 2 (31) and is connected to the main heat exchanger (2) through an oxygen delivery pipeline 1 (303). The high-purity liquid oxygen is sent to a high-purity liquid oxygen storage tank (9) after heat exchange. An oxygen outlet (304) is provided on one side of the upper part 2 (32) and is connected to the main heat exchanger (2) through an oxygen delivery pipeline 2 (305).

2. The device for extracting high-purity liquid oxygen from cryogenically distilled liquid oxygen according to claim 1, characterized in that: The nitrogen inlets of the condenser 1 (4), the condenser 2 (5) and the condenser 4 (7) are connected to the nitrogen pipeline 1 (41), the nitrogen pipeline 2 (51) and the nitrogen pipeline 4 (71) respectively; the nitrogen outlets of the condenser 1 (4) and the condenser 2 (5) are connected to the nitrogen inlet of the condenser 3 (6) through the nitrogen pipeline 3 (61); the nitrogen outlet of the condenser 4 (7) is connected to the nitrogen inlet of the condenser 5 (8) through the nitrogen pipeline 5 (81).

3. The device for extracting high-purity liquid oxygen from cryogenically distilled liquid oxygen according to claim 2, characterized in that: The nitrogen in the nitrogen pipeline three (61) is cooled by the main heat exchanger (2) and then transported to the condenser three (6), and the nitrogen in the nitrogen pipeline five (81) is cooled by the main heat exchanger (2) and then transported to the condenser five (8).

4. The device for extracting high-purity liquid oxygen from cryogenically distilled liquid oxygen according to claim 1, characterized in that: A second extraction port (111) is provided on one side of the lower portion (11), and the second extraction port (111) is connected to the inner cavity of the middle portion (12) through an external pipe (112).

5. The device for extracting high-purity liquid oxygen from cryogenically distilled liquid oxygen according to claim 1, characterized in that: A return pipe (106) is connected in parallel to the liquid oxygen delivery pipe (105), and the return pipe (106) is connected to the inner cavity of the upper part (13).

6. The device for extracting high-purity liquid oxygen from cryogenically distilled liquid oxygen according to claim 1, characterized in that: The oxygen supply pipeline 2 (305) is connected to the condenser 5 (8) through the external pipeline 2 (323), and an extraction port 3 (321) is opened on one side of the upper part 2 (32), and the extraction port 3 (321) is connected to the inner cavity of the distillation tower 2 (3) through the reflux pipeline 2 (322).

7. The device for extracting high-purity liquid oxygen from cryogenically distilled liquid oxygen according to claim 1, characterized in that: The bottom of the lower part one (11) is provided with a high boiling point component outlet (113), and the tops of the upper part one (13) and the upper part two (32) are respectively provided with a low boiling point component outlet one (131) and a low boiling point component outlet two (324), and the low boiling point components of the low boiling point component outlet one (131) and the low boiling point component outlet two (324) are recovered through the main heat exchanger (2) via a cold recovery pipe (107).

8. The device for extracting high-purity liquid oxygen from cryogenically distilled liquid oxygen according to claim 1, characterized in that: The second liquid oxygen inlet (301) of the second distillation tower (3) is arranged in the middle of the second distillation tower (3).

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