Single-pump internal compression air separation device capable of simultaneously producing high-purity oxygen

Abstract

The utility model relates to the technical field, in particular to a single-pump internal compression air separation device capable of simultaneously producing high-purity oxygen, which comprises a fractionating tower, a front component and a pressurizing component, the front component and the pressurizing component are communicated, and the fractionating tower comprises a main heat exchanger, a subcooler, a liquid oxygen pump, a lower tower, an upper tower and a main condensation evaporator connected between the lower tower and the upper tower. The fractionating tower further comprises a synergistic tower condenser, a synergistic tower, a high-purity oxygen tower and a high-purity oxygen tower evaporator which are communicated, the main heat exchanger is communicated with the front assembly, the pressurizing assembly, the subcooler, the lower tower, the liquid oxygen pump and the high-purity oxygen tower evaporator, and the subcooler is communicated with the lower tower, the main condensing evaporator, the upper tower and the synergistic tower condenser. The lower tower is communicated with the pressurizing assembly, the main condensation evaporator and the high-purity oxygen tower evaporator, the main condensation evaporator is communicated with the liquid oxygen pump, and the upper tower is communicated with the synergistic tower condenser and the synergistic tower. The single-pump internal compression air separation device capable of simultaneously producing high-purity oxygen can produce oxygen, nitrogen, high-purity liquid oxygen and high-purity liquid oxygen.

Description

Technical Field

[0001] This utility model relates to the field of air separation equipment technology, specifically to a single-pump internal compression air separation unit that simultaneously produces high-purity oxygen. Background Technology

[0002] The main principle of large and medium-sized industrial air separation units is to liquefy air at low temperatures and then separate it through distillation to obtain products such as oxygen and nitrogen. Air undergoes preliminary separation in the lower column to obtain pure nitrogen at the top and oxygen-enriched liquid air at the bottom. The liquid nitrogen and oxygen-enriched liquid air from the lower column then enter the upper column for secondary distillation to obtain oxygen (liquid oxygen) and nitrogen products. Single-pump internal compression air separation units are further divided into two processes: with and without argon. The single-pump internal compression process without argon reduces the distillation efficiency of the upper column due to the influence of argon on oxygen and nitrogen distillation, resulting in lower overall extraction and a more limited product form. In contrast, the single-pump internal compression process with argon extracts argon, the main impurity in the oxygen product, thus improving the extraction rate of the air separation unit.

[0003] Therefore, how to design a single-pump internal compression air separation unit that can simultaneously produce high-purity oxygen, improve the oxygen extraction rate without argon in single-pump internal compression, and improve the distillation effect in the upper column without increasing energy consumption, has become a problem that we urgently need to solve. Utility Model Content

[0004] To address the technical problems of low oxygen extraction rate and poor distillation effect in existing single-pump internal compression air separation units without argon, resulting in a limited range of product forms, this invention provides a single-pump internal compression air separation unit that simultaneously produces high-purity oxygen. While producing oxygen and nitrogen products, it can also simultaneously produce high-purity liquid oxygen and liquid oxygen products, thus enriching the product range. The configured enhancement column can remove the influence of argon components on the upper column distillation, thereby improving the distillation separation efficiency.

[0005] The present invention adopts the following technical solution:

[0006] This utility model provides a single-pump internal compression air separation unit that simultaneously produces high-purity oxygen, including a fractionation column, a pre-treatment component and a pressurization component connected in series. The fractionation column includes a main heat exchanger, a subcooler, a liquid oxygen pump, a lower column, an upper column, and a main condenser-evaporator connected between the lower column and the upper column. The fractionation column also includes an enhancement column condenser, an enhancement column, a high-purity oxygen column, and a high-purity oxygen column evaporator connected in series. The main heat exchanger is connected to the pre-treatment component, the pressurization component, the subcooler, the lower column, the liquid oxygen pump, and the high-purity oxygen column evaporator. The subcooler is connected to the lower column, the main condenser-evaporator, the upper column, and the enhancement column condenser. The lower column is connected to the pressurization component, the main condenser-evaporator, and the high-purity oxygen column evaporator. The main condenser-evaporator is connected to the liquid oxygen pump. The upper column is connected to the enhancement column condenser and the enhancement column.

[0007] Furthermore, the pressurization assembly includes an air booster and a turboexpander. The air booster is connected to the turboexpander via air pipe two. The turboexpander is connected to the main heat exchanger via air pipe three. The main heat exchanger is connected to the turboexpander via air pipe four. The turboexpander is connected to the lower tower via air pipe five. The air booster is connected to the main heat exchanger via air pipe six. The main heat exchanger is connected to the lower tower via liquid-air pipe five.

[0008] Furthermore, the pre-processing components include an air compression system, an air precooling system, and a molecular sieve purification system connected in sequence. The molecular sieve purification system is connected to an air booster via an air duct one. The molecular sieve purification system is connected to the main heat exchanger via an air duct seven. The main heat exchanger is connected to the lower tower via an air duct eight. The main heat exchanger is connected to the pure oxygen tower evaporator via an air duct nine. The high-purity oxygen tower evaporator is connected to the lower tower via a liquid-air duct six.

[0009] Furthermore, the lower column is connected to the subcooler via liquid air pipeline one, the subcooler is connected to the upper column via liquid air pipeline two, the upper column is also connected to the subcooler via waste nitrogen pipeline one, the subcooler is connected to the condenser of the enhancement column via liquid air pipeline three, the condenser of the enhancement column is connected to the enhancement column, the condenser of the enhancement column is connected to the waste nitrogen pipeline one via waste nitrogen pipeline four, and the condenser of the enhancement column is connected to the upper column via liquid air vapor pipeline four.

[0010] Furthermore, the subcooler is connected to the main heat exchanger via a second waste nitrogen pipe, and the main heat exchanger outputs waste nitrogen gas via a third waste nitrogen pipe.

[0011] Furthermore, the lower column is connected to the subcooler via a lean liquid-air pipe one, and the subcooler is connected to the upper column inlet via a lean liquid-air pipe two.

[0012] Furthermore, the lower tower is connected to the main heat exchanger via nitrogen pipeline two, and the main heat exchanger outputs nitrogen via nitrogen pipeline three.

[0013] Furthermore, the lower tower is connected to the main condenser-evaporator via nitrogen pipeline one, and the main condenser-evaporator is connected to the upper tower. The main condenser-evaporator is connected to the lower tower via liquid nitrogen pipeline one, the main condenser-evaporator is connected to the subcooler via liquid nitrogen pipeline two, and the subcooler is connected to the upper tower via liquid nitrogen pipeline three.

[0014] Furthermore, the upper tower is connected to the main condenser-evaporator, the main condenser-evaporator is connected to the liquid oxygen pump through liquid oxygen pipeline one, the liquid oxygen pump is connected to the main heat exchanger through liquid oxygen pipeline two, and the main heat exchanger outputs oxygen through the oxygen pipeline.

[0015] Furthermore, the upper column is connected to the enhancement column via an argon fraction pipeline, and the enhancement column is connected to the upper column via a liquid oxygen pipeline six; the enhancement column is connected to the high-purity oxygen column via a liquid oxygen pipeline three, the high-purity oxygen column is connected to the enhancement column via a crude oxygen pipeline, the high-purity oxygen column outputs high-purity oxygen via a liquid oxygen pipeline four, and the high-purity oxygen column outputs liquid oxygen via a liquid oxygen pipeline five.

[0016] Compared with the prior art, the present invention has the following technical effects:

[0017] This invention relates to a single-pump internal compression air separation unit. It utilizes an enhancement tower to initially remove impurities (argon components) from liquid oxygen, followed by further rectification of the liquid oxygen in a high-purity oxygen tower. The purified liquid oxygen is then produced as high-purity liquid oxygen and liquid oxygen products. This single-pump internal compression air separation unit can simultaneously produce oxygen and nitrogen products, as well as high-purity liquid oxygen and liquid oxygen products. The enhancement tower effectively eliminates the influence of argon components on the rectification process in the upper tower, thereby improving the rectification and separation efficiency, increasing the product extraction rate by approximately 4%, and improving the utilization rate of the feed air while reducing production consumption. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a single-pump internal compression air separation device that simultaneously produces high-purity oxygen according to this utility model.

[0019] The numbers in the attached diagram are:

[0020] 1. Air compression system; 2. Air precooling system; 3. Molecular sieve purification system; 4. Air booster compressor; 5. Fractionating tower; 6. Booster turbine expander; 7. Main heat exchanger; 8. Subcooler; 9. Lower tower; 10. Main condenser-evaporator; 11. Upper tower; 12. Liquid oxygen pump; 13. Enhancement tower condenser; 14. Enhancement tower; 15. High-purity oxygen tower; 16. High-purity oxygen tower evaporator;

[0021] 201. Air Pipeline 1; 202. Air Pipeline 2; 203. Air Pipeline 3; 204. Air Pipeline 4; 205. Air Pipeline 5; 206. Air Pipeline 6; 207. Liquid Air Pipeline 5; 103. Air Pipeline 7; 105. Air Pipeline 8; 106. Air Pipeline 9; 107. Liquid Air Pipeline 6; 301. Liquid Air Pipeline 1; 302. Liquid Air Pipeline 2; 303. Liquid Air Pipeline 3; 304. Liquid Air Steam Pipeline 4; 311. Lean Liquid Air Pipeline 1; 312. Lean Liquid Air Pipeline 2; 320. Nitrogen Pipeline 1; 321A. Liquid Nitrogen Pipeline Pipeline 1; 321B, Liquid Nitrogen Pipeline 2; 322, Liquid Nitrogen Pipeline 3; 330, Waste Nitrogen Pipeline 1; 331, Waste Nitrogen Pipeline 2; 332, Waste Nitrogen Pipeline 3; 340, Nitrogen Pipeline 2; 341, Nitrogen Pipeline 3; 350, Liquid Oxygen Pipeline 1; 351, Liquid Oxygen Pipeline 2; 352, Oxygen Pipeline; 701, Argon Fraction Pipeline; 702, Liquid Oxygen Pipeline 6; 703, Connecting Pipeline 1; 704, Connecting Pipeline 2; 705, Waste Nitrogen Pipeline 4; 710, Liquid Oxygen Pipeline 3; 711, Crude Oxygen Pipeline; 712, Liquid Oxygen Pipeline 4; 713, Liquid Oxygen Pipeline 5. Detailed Implementation

[0022] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0023] like Figure 1 As shown, a single-pump internal compression air separation unit that simultaneously produces high-purity oxygen includes a fractionating column 5, a pre-treatment component, and a pressurizing component connected in series. In operation, the fractionating column 5, the pre-treatment component, and the pressurizing component are installed on the working ground. The fractionating column 5 includes a main heat exchanger 7, a subcooler 8, a liquid oxygen pump 12, a lower column 9, an upper column 11, and a main condenser-evaporator 10 connected between the lower column 9 and the upper column 11. The fractionating column 5 also includes a connected enhancement column condenser 13, an enhancement column 14, a high-purity oxygen column 15, and a high-purity oxygen column. The pure oxygen tower evaporator 16 is connected to the main heat exchanger 7, the preheating assembly, the pressurizing assembly, the subcooler 8, the lower tower 9, the liquid oxygen pump 12, and the high-purity oxygen tower evaporator 16. The subcooler 8 is connected to the lower tower 9, the main condenser-evaporator 10, the upper tower 11, and the enhancement tower condenser 13. The lower tower 9 is connected to the pressurizing assembly, the main condenser-evaporator 10, and the high-purity oxygen tower evaporator 16. The main condenser-evaporator 10 is connected to the liquid oxygen pump 12. The upper tower 11 is connected to the enhancement tower condenser 13 and the enhancement tower 14. The lower tower 9, the upper tower 11, the enhancement tower 14, and the pure oxygen tower 15 are all structured packed distillation columns. The main heat exchanger 7 and the subcooler 8 are both plate-fin heat exchangers. The main condenser-evaporator 10, the enhancement tower condenser 13, and the pure oxygen tower evaporator 16 are all bath-type evaporators (condensers).

[0024] In this embodiment, the single-pump internal compression air separation unit uses an enhancement tower 14 to perform preliminary impurity removal (removal of argon components) on liquid oxygen, and then configures a high-purity oxygen tower 15 to further distill the liquid oxygen. After purification, high-purity liquid oxygen products and liquid oxygen products are produced, which enriches the product types and improves the economic benefits of the air separation unit. Compared with traditional air separation units, it can achieve better economic benefits and applicable scenarios.

[0025] The single-pump internal compression air separation unit in this embodiment can simultaneously produce oxygen and nitrogen products, as well as high-purity liquid oxygen and liquid oxygen products. The configured enhancement column 14 can remove the influence of argon components on the upper column distillation, thereby improving the distillation separation efficiency, increasing the product extraction rate by about 4%, improving the utilization rate of raw material air, and reducing production consumption.

[0026] In one possible implementation, the pressurization assembly includes an air booster 4 and a turboexpander 6. The air outlet of the air booster 4 is connected to the booster inlet of the turboexpander 6 via air pipe 202. The booster outlet of the turboexpander 6 is connected to the expansion air inlet of the main heat exchanger 7 via air pipe 303. The expansion air outlet of the main heat exchanger 7 is connected to the expansion inlet of the turboexpander 6 via air pipe 404. The expansion outlet of the turboexpander 6 is connected to the expansion air inlet of the lower tower 9 via air pipe 505. The air outlet of the molecular sieve purification system 3 is divided into two paths. One path, with purified air, is connected to the inlet of the air booster 4 via air pipe 201. A portion of the air in compressor 4 is drawn out as expansion air from the air outlet of air booster compressor 4 and enters the booster end of booster turbine expander 6 through air pipe 202 for pressurization. The air at the outlet of booster turbine expander 6 enters the expansion air inlet of main heat exchanger 7 through air pipe 303 and exchanges heat with the backflowing nitrogen and sludge nitrogen to cool down. The cooled expansion air enters the expansion end of booster turbine expander 6 through the expansion air outlet of main heat exchanger 7 and air pipe 404 for expansion and cooling. The expansion end of booster turbine expander 6 is also located in fractionation tower 5. The expanded and cooled expansion air at the outlet of booster turbine expander 6 is connected to the expansion air inlet of lower tower 9 through air pipe 505 and enters lower tower 9 to participate in distillation and separation.

[0027] Furthermore, the final air outlet of the air booster 4 is connected to the pressurized air inlet of the main heat exchanger 7 via air pipe six 206, and the pressurized air outlet of the main heat exchanger 7 is connected to the liquid air inlet of the lower tower 9 via liquid air pipe five 207. The remaining air entering the air booster 4 is further pressurized by the air booster 4 to obtain high-pressure air. The high-pressure air is drawn out from the final air outlet of the air booster 4 and enters the main heat exchanger 7 via air pipe six 206 and the pressurized air inlet of the main heat exchanger 7. In the main heat exchanger 7, it exchanges heat with the backflowing high-pressure liquid oxygen, etc., and the high-pressure air is cooled into high-pressure liquid air. The pressurized air outlet of the main heat exchanger 7 is connected to the liquid air inlet of the lower tower 9 via liquid air pipe five 207, and the high-pressure liquid air enters the lower tower to participate in distillation; at the same time, the high-pressure liquid oxygen is vaporized and reheated into high-pressure oxygen and sent out of the main heat exchanger 7.

[0028] In one possible implementation, the pre-processing components include an air compression system 1, an air precooling system 2, and a molecular sieve purification system 3 connected in sequence. The air compression system 1 pressurizes the raw material air before it enters the air precooling system 2, which cools the air to approximately 10°C before it enters the molecular sieve purification system 3 for drying, purification, and removal of impurities such as carbon dioxide. The air outlet of the molecular sieve purification system 3 has two branches. One branch, containing purified air, connects to the inlet of an air booster 4 via an air pipe 201. The air outlet of the molecular sieve purification system 3 is also connected to the inlet of the air booster 4 via the air pipe 201. The air compression system 1, air precooling system 2, and molecular sieve purification system 3 are equipment systems, and their structure is existing technology, which will not be described in detail here.

[0029] The air outlet of the molecular sieve purification system 3 is connected to the low-pressure air inlet of the main heat exchanger 7 via air pipe 7 103. The air outlet of the main heat exchanger 7 is connected to the air inlet of the lower tower 9 via air pipe 8 105. The air outlet of the main heat exchanger 7 is also connected to the air inlet of the pure oxygen tower evaporator 16 via air pipe 9 106. The liquid air outlet of the high-purity oxygen tower evaporator 16 is connected to the liquid air inlet of the lower tower 9 via liquid air pipe 6 107. The purified air from the molecular sieve purification system 3 is connected to the low-pressure air inlet of the main heat exchanger 7 via air pipe 7 103. It exchanges heat with nitrogen, waste nitrogen, oxygen, etc. that are flowing back into the main heat exchanger 7 and is cooled down to near liquefaction. Then, it splits into two streams from the air outlet of the main heat exchanger 7. One stream of air is connected to the air inlet of the lower tower 9 via air pipe 8 105 and enters the lower tower 9 directly to participate in the distillation. The other stream of air enters the high-purity oxygen tower evaporator 16 via air pipe 9 106 and the air inlet of the high-purity oxygen tower evaporator 16 to provide a heat source. It exchanges heat with the liquid oxygen in the high-purity oxygen tower evaporator 16 and liquefies itself into liquid air. At the same time, it vaporizes the liquid oxygen to provide rising gas conditions for the distillation of the high-purity oxygen tower 15. The liquid air enters the lower tower 9 via the liquid air outlet of the high-purity oxygen tower evaporator 16, the liquid air pipe 6 107, and the liquid air inlet of the lower tower 9 to participate in the distillation.

[0030] In one possible implementation, the liquid air outlet at the bottom of the lower column 9 is connected to the liquid air inlet of the subcooler 8 via liquid air pipe 1 301; the liquid air outlet of the subcooler 8 is connected to the liquid air inlet of the upper column 11 via liquid air pipe 2 302; the waste nitrogen outlet at the top of the upper column 11 is connected to the waste nitrogen inlet of the subcooler 8 via waste nitrogen pipe 1 330; the liquid air outlet of the subcooler 8 is connected to the liquid air inlet of the enhancement column condenser 13 via liquid air pipe 3 303; the argon inlet of the enhancement column condenser 13 is connected to the argon outlet of the enhancement column 14; the enhancement column condenser 13 and the enhancement column 14 are connected via connecting pipe 1 703 and connecting pipe 2 704; the enhancement column condenser 13 is connected to the waste nitrogen pipe 1 330 via waste nitrogen pipe 4 705; and the liquid air vapor of the enhancement column condenser 13 is connected to the liquid air vapor inlet in the middle of the upper column 11 via liquid air vapor pipe 4 304.

[0031] The air feedstock in the lower column 9 undergoes initial separation, yielding pure nitrogen at the top and lean liquid air and oxygen-enriched liquid air at the bottom and bottom of the lower column 9, respectively. The liquid air outlet at the bottom of the lower column 9 is connected to the liquid air inlet of the subcooler 8 via liquid air pipe 301. The liquid air outlet of the subcooler 8 is divided into two streams. One stream, oxygen-enriched liquid air, enters the upper column 11 via liquid air pipe 302 and the liquid air inlet of the upper column 11, participating in the rectification of the upper column 11. Another stream of oxygen-rich liquid air enters the condenser 13 through liquid air pipeline 303 and the liquid air inlet of the condenser 13, providing a cooling source. In the condenser 13, the oxygen-rich liquid air exchanges heat with the crude argon gas entering the condenser 13 and is vaporized into liquid air vapor. The liquid air vapor in the condenser 13 enters the upper column 9 through liquid air vapor pipeline 404 and the liquid air vapor inlet in the middle of the upper column 11 and participates in the rectification of the upper column 9. The crude argon gas is partially liquefied and the gas phase is sent to the nitrogen-rich waste gas pipeline 330 for recovery of cooling capacity. The liquid phase of argon-rich liquid oxygen enters the condenser 14 and serves as the reflux liquid of the condenser 14 to maintain the rectification process of the condenser 14.

[0032] In one possible implementation, the lean liquid air outlet at the bottom of the lower column 9 is connected to the lean liquid air inlet of the subcooler 8 via lean liquid air pipe 311, and the lean liquid air outlet of the subcooler 8 is connected to the lean liquid air inlet of the upper column 11 via lean liquid air pipe 312. The lean liquid air at the lower column 9 is connected to the lean liquid air inlet of the subcooler 8 via lean liquid air pipe 311, and the lean liquid air from the subcooler 8 enters the upper column 9 via lean liquid air pipe 312 and the lean liquid air inlet of the upper column 11, participating in the distillation of the upper column 9.

[0033] In one possible implementation, the top of the lower column 9 is connected to the nitrogen inlet of the main heat exchanger 7 via nitrogen pipeline 2 340, and the nitrogen outlet of the main heat exchanger 7 outputs nitrogen via nitrogen pipeline 341. A portion of the nitrogen at the top of the lower column 9 is connected to the nitrogen inlet of the main heat exchanger 7 via nitrogen pipeline 2 340, and the nitrogen outlet of the main heat exchanger 7 outputs nitrogen via nitrogen pipeline 341, ultimately enabling the nitrogen product to be delivered out of the fractionation tower cold box 5.

[0034] In one possible implementation, the top of the lower tower 9 is connected to the nitrogen inlet of the main condenser-evaporator 10 via a nitrogen pipe 320, and the main condenser-evaporator 10 is connected to the upper tower 11. The liquid nitrogen outlet of the main condenser-evaporator 10 is connected to the liquid nitrogen inlet of the lower tower 9 via a liquid nitrogen pipe 321A, the liquid nitrogen outlet of the main condenser-evaporator 10 is connected to the liquid nitrogen inlet of the subcooler 8 via a liquid nitrogen pipe 321B, and the liquid nitrogen outlet of the subcooler 8 is connected to the liquid nitrogen inlet at the top of the upper tower 11 via a liquid nitrogen pipe 322. The remaining nitrogen at the top of the lower column 9 is connected to the nitrogen inlet of the main condenser-evaporator 10 via nitrogen pipeline 320, and enters the main condenser-evaporator 10 to exchange heat with the liquid oxygen from the upper column 9. The liquid oxygen vaporizes and serves as the rising gas in the upper column 9 to maintain the rectification of the upper column 9, while the nitrogen is liquefied into liquid nitrogen. The liquid nitrogen outlet of the main condenser-evaporator 10 is split into two paths via liquid nitrogen pipeline 321. One path of liquid nitrogen enters the lower column 9 via liquid nitrogen pipeline 321A and the liquid nitrogen inlet of the lower column 9 as the reflux liquid at the top of the lower column 9. The other path of liquid nitrogen enters the subcooler 8 via liquid nitrogen pipeline 321B and the liquid nitrogen inlet of the subcooler 8. The liquid nitrogen outlet of the subcooler 8 is connected to the liquid nitrogen inlet at the top of the upper column 11 via liquid nitrogen pipeline 322, and the liquid nitrogen then enters the upper column 11 as the reflux liquid at the top of the upper column 11. If necessary, a small amount of liquid nitrogen can also be extracted as liquid nitrogen product and sent out of the fractionation column cold box 5.

[0035] In one possible implementation, the upper column 11 is connected to the main condenser-evaporator 10, which is connected to a liquid oxygen pump 12 via a liquid oxygen pipeline 350. The liquid oxygen pump 12 is connected to the liquid oxygen inlet of the main heat exchanger 7 via a liquid oxygen pipeline 351, and the oxygen outlet of the main heat exchanger 7 outputs oxygen via an oxygen pipeline 352. Further distillation in the upper column 11 yields liquid oxygen at its bottom, argon fraction at its middle argon enrichment zone, and waste nitrogen, which includes nitrogen and other gases, at its top. The liquid oxygen obtained from the distillation of the upper column 11 is mainly stored in the main condenser-evaporator 10. The liquid oxygen in the main condenser-evaporator 10 is connected to the inlet of the liquid oxygen pump 12 through the liquid oxygen pipeline 350. The liquid oxygen pressurized by the liquid oxygen pump 12 is connected to the liquid oxygen inlet of the main heat exchanger 7 through the liquid oxygen pipeline 351. After the pressurized liquid oxygen exchanges heat with high-pressure air, expanded air and low-pressure air in the main heat exchanger 7, it is vaporized and reheated into high-pressure oxygen product. The oxygen outlet of the main heat exchanger 7 outputs oxygen product through the oxygen pipeline 352, and finally the oxygen product is sent out of the fractionation tower cold box 5.

[0036] In one possible implementation, the waste nitrogen outlet of the subcooler 8 is connected to the waste nitrogen inlet of the main heat exchanger 7 via waste nitrogen pipe 2 331, and the waste nitrogen outlet of the main heat exchanger 7 outputs waste nitrogen via waste nitrogen pipe 332. The waste nitrogen outlet of the subcooler 8 is connected to the waste nitrogen inlet of the main heat exchanger 7 via waste nitrogen pipe 2 331, and the waste nitrogen outlet of the main heat exchanger 7 sends the waste nitrogen out of the fractionation tower 6 via waste nitrogen pipe 332. Furthermore, the waste nitrogen can be used by the air precooling system 2 and the molecular sieve purification system 3.

[0037] In one possible implementation, the middle section of the upper column 11 is connected to the argon fraction inlet of the enhancement column 14 via an argon fraction pipeline 701. The lean argon liquid oxygen outlet at the bottom of the enhancement column 14 is connected to the lean argon liquid oxygen inlet of the upper column 11 via a liquid oxygen pipeline 702. The argon fraction in the middle section of the upper column 11 is connected to the argon fraction inlet of the enhancement column 14 via the argon fraction pipeline 701. The argon fraction enters the enhancement column 14 for rectification and separation, resulting in argon-rich waste gas at the condenser outlet at the top of the enhancement column 14 and lean argon liquid oxygen at the bottom of the column. The argon-rich waste gas obtained at the condenser outlet 13 at the top of the enhancement column 14 is connected to the waste nitrogen pipeline 330 via a pipeline 705. The argon-rich waste gas is sent into the waste nitrogen pipeline 330 and finally vented after recovering its cooling capacity. The bottom outlet of the booster column 14, which is a lean argon liquid oxygen, is connected to the inlet of the upper column 11, which is a lean argon liquid oxygen, through a liquid oxygen pipeline 702. The lean argon liquid oxygen enters the upper column 11 for further distillation. The booster column achieves preliminary removal of impurities (removal of argon components) from the liquid oxygen and improves the distillation separation efficiency.

[0038] The lower part of the enhancement tower 14 is connected to the crude liquid oxygen inlet at the top of the high-purity oxygen tower 15 via liquid oxygen pipeline 3 710. The top of the high-purity oxygen tower 15 is connected to the lower oxygen inlet of the enhancement tower 14 via crude oxygen pipeline 711. The high-purity liquid oxygen outlet at the bottom of the high-purity oxygen tower 15 outputs high-purity oxygen via liquid oxygen pipeline 4 712. The liquid oxygen outlet at the bottom of the high-purity oxygen tower 15 outputs liquid oxygen via liquid oxygen pipeline 5 713.

[0039] A stream of crude liquid oxygen, having undergone distillation to remove most hydrocarbon impurities, is drawn from the lower part of the enhancement tower 14. This crude liquid oxygen then enters the high-purity oxygen tower 15 through liquid oxygen pipeline 3 710 and the crude liquid oxygen inlet at the top of the high-purity oxygen tower 15 for further distillation and purification. After further distillation and purification, ordinary liquid oxygen is obtained at the bottom of the high-purity oxygen tower 15, high-purity oxygen (liquid oxygen) is obtained at the bottom, and crude oxygen is obtained at the top. The crude oxygen at the top of the high-purity oxygen tower 15 returns to the enhancement tower 14 through oxygen pipeline 711 for further distillation. The high-purity oxygen (liquid oxygen) product at the bottom of the high-purity oxygen tower 15 is sent out of the fractionation tower cold box 5 through liquid oxygen pipeline 4 712, and the ordinary liquid oxygen product at the bottom of the high-purity oxygen tower 15 is sent out of the fractionation tower cold box 5 through liquid oxygen pipeline 5 713.

[0040] The embodiments described above are merely preferred embodiments of this utility model and are only used to explain this utility model. They are not intended to limit the scope of implementation of this utility model. For those skilled in the art, other implementation methods can be easily made by substitution or modification based on the technical content disclosed in this specification. Therefore, all changes and improvements made to the principles and process conditions of this utility model should be included within the scope of the patent application of this utility model.

Claims

1. A single-pump internal compression air separation unit for simultaneously producing high-purity oxygen, comprising a fractionating column (5), a pre-processing unit and a pressurizing unit connected in series, wherein the fractionating column (5) comprises a main heat exchanger (7), a subcooler (8), a liquid oxygen pump (12), a lower column (9), an upper column (11), and a main condenser-evaporator (10) connected between the lower column (9) and the upper column (11), characterized in that, The fractionation tower (5) also includes a connected booster tower condenser (13), booster tower (14), high-purity oxygen tower (15), and high-purity oxygen tower evaporator (16). The main heat exchanger (7) is connected to the pre-heating component, the pressurizing component, the subcooler (8), the lower tower (9), the liquid oxygen pump (12), and the high-purity oxygen tower evaporator (16). The subcooler (8) is connected to the lower tower (9), the main condenser evaporator (10), the upper tower (11), and the booster tower condenser (13). The lower tower (9) is connected to the pressurizing component, the main condenser evaporator (10), and the high-purity oxygen tower evaporator (16). The main condenser evaporator (10) is connected to the liquid oxygen pump (12). The upper tower (11) is connected to the booster tower condenser (13) and the booster tower (14).

2. The single-pump internal compression air separation device according to claim 1, characterized in that, The pressurization assembly includes an air booster (4) and a pressurized turbine expander (6). The air booster (4) is connected to the pressurized turbine expander (6) via air pipe two (202). The pressurized turbine expander (6) is connected to the main heat exchanger (7) via air pipe three (203). The main heat exchanger (7) is connected to the pressurized turbine expander (6) via air pipe four (204). The pressurized turbine expander (6) is connected to the lower tower (9) via air pipe five (205). The air booster (4) is connected to the main heat exchanger (7) via air pipe six (206). The main heat exchanger (7) is connected to the lower tower (9) via liquid air pipe five (207).

3. The single-pump internal compression air separation device according to claim 2, characterized in that, The pre-assembly includes an air compression system (1), an air precooling system (2), and a molecular sieve purification system (3) connected in sequence. The molecular sieve purification system (3) is connected to an air booster (4) through an air pipe (201). The molecular sieve purification system (3) is connected to a main heat exchanger (7) through an air pipe (7) (103). The main heat exchanger (7) is connected to a lower tower (9) through an air pipe (8) (105). The main heat exchanger (7) is connected to a pure oxygen tower evaporator (16) through an air pipe (9) (106). The high-purity oxygen tower evaporator (16) is connected to the lower tower (9) through a liquid air pipe (6) (107).

4. The single-pump internal compression air separation device according to claim 1, characterized in that, The lower tower (9) is connected to the subcooler (8) via liquid air pipeline one (301). The subcooler (8) is connected to the upper tower (11) via liquid air pipeline two (302). The upper tower (11) is also connected to the subcooler (8) via waste nitrogen pipeline one (330). The subcooler (8) is connected to the enhancement tower condenser (13) via liquid air pipeline three (303). The enhancement tower condenser (13) is connected to the enhancement tower (14). The enhancement tower condenser (13) is connected to the waste nitrogen pipeline one (330) via waste nitrogen pipeline four (705). The enhancement tower condenser (13) is connected to the upper tower (11) via liquid air vapor pipeline four (304).

5. The single-pump internal compression air separation device according to claim 4, characterized in that, The subcooler (8) is connected to the main heat exchanger (7) through the second waste nitrogen pipeline (331), and the main heat exchanger (7) outputs waste nitrogen gas through the third waste nitrogen pipeline (332).

6. The single-pump internal compression air separation device according to claim 1, characterized in that, The lower tower (9) is connected to the subcooler (8) via a lean liquid-air pipe one (311), and the subcooler (8) is connected to the upper tower (11) via a lean liquid-air pipe two (312).

7. The single-pump internal compression air separation device according to claim 1, characterized in that, The lower tower (9) is connected to the main heat exchanger (7) through nitrogen pipeline two (340), and the main heat exchanger (7) outputs nitrogen through nitrogen pipeline three (341).

8. The single-pump internal compression air separation device according to claim 7, characterized in that, The lower tower (9) is connected to the main condenser-evaporator (10) via nitrogen pipeline 1 (320), and the main condenser-evaporator (10) is connected to the upper tower (11). The main condenser-evaporator (10) is connected to the lower tower (9) via liquid nitrogen pipeline 1 (321A), the main condenser-evaporator (10) is connected to the subcooler (8) via liquid nitrogen pipeline 2 (321B), and the subcooler (8) is connected to the upper tower (11) via liquid nitrogen pipeline 3 (322).

9. The single-pump internal compression air separation device according to claim 1, characterized in that, The upper tower (11) is connected to the main condenser-evaporator (10), the main condenser-evaporator (10) is connected to the liquid oxygen pump (12) through liquid oxygen pipeline one (350), the liquid oxygen pump (12) is connected to the main heat exchanger (7) through liquid oxygen pipeline two (351), and the main heat exchanger (7) outputs oxygen through oxygen pipeline (352).

10. The single-pump internal compression air separation device according to claim 1, characterized in that, The upper tower (11) is connected to the enhancement tower (14) via an argon fraction pipeline (701), and the enhancement tower (14) is connected to the upper tower (11) via a liquid oxygen pipeline (702); the enhancement tower (14) is connected to the high-purity oxygen tower (15) via a liquid oxygen pipeline (710), and the high-purity oxygen tower (15) is connected to the enhancement tower (14) via a crude oxygen pipeline (711); the high-purity oxygen tower (15) outputs high-purity oxygen via a liquid oxygen pipeline (712), and the high-purity oxygen tower (15) outputs liquid oxygen via a liquid oxygen pipeline (713).

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