Variable-load oxygen supply device

Abstract

The utility model relates to a variable load oxygen supply device which comprises a rectifying tower, a raw material air delivery header pipe and a main heat exchanger, the rectifying tower comprises an upper tower, a condensation evaporator and a lower tower, the upper tower is communicated with a liquid air storage tank, the liquid air storage tank is communicated with a liquid oxygen evaporator, and the liquid air storage tank and the upper tower are provided with a first liquid air delivery pipe. The liquid oxygen evaporator is communicated with a liquid oxygen storage tank, the liquid oxygen storage tank is communicated with the condensation evaporator, the upper tower is provided with an oxygen conveying header pipe, and the liquid oxygen evaporator and the oxygen conveying header pipe are provided with first oxygen conveying branch pipes. Raw material air conveying branch pipes are arranged on the upper tower and the raw material air conveying header pipe, the raw material air conveying header pipe and the lower tower and the raw material air conveying header pipe and the liquid oxygen evaporator, first adjusting valves are arranged on the raw material air conveying header pipe and each raw material air conveying branch pipe, and a second adjusting valve and a booster pump are arranged on the first liquid air conveying pipe. And the process adjustment amplitude of the cryogenic rectification system is reduced. The utility model has the advantages of convenient use and wide market prospect.

Description

TECHNICAL FIELD

[0001] The utility model relates to air separation rectification equipment field, concretely relates to a variable load oxygen supply device. BACKGROUND

[0002] Fuel combustion is the exothermic and luminous violent oxidation reaction of fuel and combustion-supporting agent under certain conditions. The common fuel combustion takes air as the combustion-supporting agent, and the oxygen content participating in the combustion reaction in the air is only 21%, while the nitrogen content not participating in the combustion reaction is as high as 79%. These nitrogen absorbs a large amount of combustion reaction heat, and finally is discharged into the atmosphere with flue gas, causing great energy waste. Oxygen-enriched combustion is the combustion of fuel with oxygen content greater than 21% in the combustion-supporting agent. This combustion mode increases the useful oxygen content in the combustion-supporting agent and reduces the useless component nitrogen content in the combustion-supporting agent, which has positive significance for stabilizing the combustion process, improving the combustion efficiency and improving the heat transfer in the furnace.

[0003] According to the basic theoretical knowledge of fuel combustion, some basic characteristics of the combustion, such as the combustion reaction speed, the air consumption coefficient, the fuel consumption product generation amount and the theoretical combustion temperature, are described when the oxygen content in the combustion-supporting air is increased by using blast furnace gas as fuel. The existing process is realized by mixing high-concentration oxygen and air to form oxygen-enriched air and then delivering it to the blast furnace for combustion-supporting. There are two sources of oxygen-enriched combustion-supporting gas, one is compressed and filtered air, and the other is high-concentration oxygen. The main sources of high-concentration oxygen that the existing process can provide mainly include two kinds, one is oxygen produced by pressure swing adsorption, and the other is oxygen produced by a deep cooling rectification system. The pressure swing adsorption process is mainly suitable for the condition of small oxygen production amount, and has the advantages of easy start and stop, simple process and easy maintenance, but the production cost of oxygen per unit volume is relatively high compared with the rectification process. However, for the condition of large oxygen supply amount, the large-scale rectification process is more suitable, but once the large-scale rectification process is started, it cannot be stopped at will, because a large amount of unqualified products will be produced during the start-up and commissioning stage.

[0004] The oxygen demand of steel production enterprises fluctuates with the working condition of the blast furnace, and the production of oxygen needs to be adjusted by adjusting the amount of raw materials for the actual rectification process. Since the process flow of the deep cooling rectification process is relatively long, once the raw material gas flow is adjusted, the process parameters of the supporting equipment such as air compressor load and circulating water supply flow need to be adjusted accordingly, and the deviation of the process adjustment of the supporting equipment will directly affect the deep cooling rectification process, thereby causing problems in the quality of the final product. Therefore, during the process of adjusting the product output load of the deep cooling rectification system, the adjustment range of the process of the supporting equipment of the deep cooling rectification system is reduced, so that the deep cooling rectification system can be smoothly adjusted during the process of adjusting the product load, thereby reducing the probability of producing unqualified products. SUMMARY

[0005] In view of the defects of the prior art, the utility model provides a variable load oxygen supply device for reducing the process adjustment range of the cryogenic rectification system equipment.

[0006] The utility model discloses a technical scheme for a variable load oxygen supply device, which comprises a rectifying tower, a raw material air delivery main pipe and a main heat exchanger for gas heat exchange. The rectifying tower comprises an upper tower, a condenser evaporator and a lower tower from top to bottom. The upper tower is connected with a liquid air storage tank. The liquid air storage tank is connected with the outlet end of a liquid oxygen evaporator heat source channel. The bottom end of the liquid air storage tank and the upper tower are provided with a first liquid air delivery pipe. The liquid oxygen evaporator cold source channel is connected with a liquid oxygen storage tank. The liquid oxygen storage tank and the condenser evaporator cold source channel are connected. The upper tower is provided with an oxygen delivery main pipe. The first oxygen delivery branch pipe and the upper tower are provided with a first regulating valve on the raw material air delivery main pipe and each raw material air delivery branch pipe. The first liquid air delivery pipe is provided with a second regulating valve and a booster pump.

[0007] Preferably, the upper tower and the lower tower are provided with a second liquid air delivery pipe. The top of the upper tower is connected with the inlet end of the condenser evaporator heat source channel. The outlet end of the condenser evaporator heat source channel and the upper tower are provided with a first liquid nitrogen delivery pipe. The outlet end of the condenser evaporator heat source channel and the lower tower are provided with a second liquid nitrogen delivery pipe. The upper tower is provided with a waste nitrogen delivery pipe and a finished nitrogen gas delivery pipe. The first liquid nitrogen delivery pipe, the second liquid air delivery pipe, the waste nitrogen delivery pipe and the finished nitrogen gas delivery pipe are provided with a supercooler. The first liquid nitrogen delivery pipe, the second liquid nitrogen delivery pipe, the second liquid air delivery pipe, the waste nitrogen delivery pipe and the finished nitrogen gas delivery pipe are provided with a third regulating valve.

[0008] Preferably, the liquid air storage tank, the liquid oxygen storage tank and the liquid oxygen evaporator cold source channel are provided with a liquid level sensor.

[0009] Preferably, the liquid oxygen evaporator and the liquid oxygen storage tank are provided with a first liquid oxygen delivery pipe. The condenser evaporator and the liquid oxygen storage tank are provided with a second liquid oxygen delivery pipe. The second liquid oxygen delivery pipe and the first liquid oxygen delivery pipe are provided with a fourth regulating valve.

[0010] Preferably, the top of the liquid air storage tank is provided with a first pressure relief valve, the first oxygen delivery branch pipe is sequentially provided with an outlet end of a pressure relief pipe, a second pressure relief valve and a pressure sensor along the direction of the liquid oxygen evaporator and the oxygen delivery header, the inlet end of the pressure relief pipe is communicated with the top end of the liquid oxygen storage tank, and a self-standing regulating valve is arranged on the pressure relief pipe.

[0011] Preferably, the first oxygen delivery branch pipe between the outlet end of the pressure relief pipe and the liquid oxygen evaporator is provided with an outlet end of a second oxygen delivery branch pipe, the inlet end of the second oxygen delivery branch pipe is communicated with the liquid oxygen storage tank, the second oxygen delivery branch pipe is sequentially provided with a fifth regulating valve, a cold source channel of the air-cooled heat exchanger and a first one-way valve along the direction from the liquid oxygen storage tank to the liquid oxygen storage tank, and a second one-way valve is arranged between the second oxygen delivery branch pipe and the liquid oxygen evaporator.

[0012] Preferably, the bottom end of the lower column and the bottom end of the condenser evaporator cold source channel are respectively provided with discharge pipes, and the discharge pipes are provided with stop valves.

[0013] The beneficial effects of the present application are as follows: first, the total amount of raw material air delivered to the raw material air delivery header in the upstream is not adjusted, so it is not necessary to adjust the load of the air separation precooling system and the air compressor set in the upstream of the rectification system, so that the raw material air delivery header can continuously and stably obtain the raw material air with stable process parameters; the flow of compressed air delivered to the lower column does not need to be adjusted, so that the rectification state of the lower column can be continuously and stably maintained, and on the basis of keeping the flow of product oxygen delivered to the oxygen delivery header unchanged, the additional oxygen required by the blast furnace is provided by the oxygen vaporized by heat exchange of the liquid oxygen stored in the liquid oxygen evaporator cold source channel and the oxygen vaporized by the cold source channel of the air-cooled heat exchanger delivered by the liquid oxygen storage tank, so that the adjustment range of the process of the cryogenic rectification system equipment is reduced.

[0014] Secondly, the liquid level sensors are arranged on the liquid air storage tank, the liquid oxygen storage tank and the liquid oxygen evaporator cold source channel respectively; the liquid level sensors are convenient for feeding back the liquid level.

[0015] Finally, the bottom end of the lower column and the bottom end of the condenser evaporator cold source channel are respectively provided with discharge pipes, and the discharge pipes are provided with stop valves; so that the discharge pipes can be used to quickly discharge the medium and then perform maintenance in the shutdown and maintenance stage.

[0016] The present application has the advantages of simple structure, convenient operation, ingenious design, greatly improved work efficiency, good social and economic benefits, and is a product easy to popularize and use. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 The figure is a structural schematic view of the present application. Detailed Implementation

[0018] like Figure 1 As shown, a variable load oxygen supply device includes a distillation column, a raw material air delivery main 1, and a main heat exchanger 2 for gas heat exchange. The distillation column, from top to bottom, includes an upper column 3, a condenser-evaporator 4, and a lower column 5. The upper column 3 is connected to a liquid air storage tank 6, and the inlet end of the liquid air storage tank 6 is connected to the outlet end of the heat source channel of the liquid oxygen evaporator 7. A first liquid air delivery pipe 8 is provided at the bottom end of the liquid air storage tank 6 and on the upper column 3. A liquid oxygen storage tank 9 is connected to the cold source channel of the liquid oxygen evaporator 7, and the liquid oxygen storage tank 9 is connected to the cold source channel of the condenser-evaporator 4. An oxygen delivery main is provided on the upper column 3. 10. A first oxygen delivery branch pipe 11 is provided between the cold source channel of the liquid oxygen evaporator 7 and the oxygen delivery main pipe 10. Raw material air delivery branch pipes 12 are provided between the upper tower 3 and the raw material air delivery main pipe 1, between the raw material air delivery main pipe 1 and the lower tower 5, and between the raw material air delivery main pipe 1 and the inlet end of the heat source channel of the liquid oxygen evaporator 7. A first regulating valve 13 is provided on the raw material air delivery main pipe 1 between the first oxygen delivery branch pipe 11 and the upper tower 3, and on each raw material air delivery branch pipe 12. A second regulating valve 14 and a booster pump 15 are provided on the first liquid air delivery pipe 8. The upper tower 3 and the lower tower 5 are provided with a second liquid air conveying pipe 16. The top of the upper tower 3 is connected to the inlet end of the heat source channel of the condenser evaporator 4. A first liquid nitrogen conveying pipe 17 is provided between the outlet end of the heat source channel of the condenser evaporator 4 and the upper tower 3. A second liquid nitrogen conveying pipe 18 is provided between the outlet end of the heat source channel of the condenser evaporator 4 and the lower tower 5. The upper tower 3 is provided with a waste nitrogen conveying pipe 19 and a finished nitrogen conveying pipe 20. An overcooler 21 is provided on the first liquid nitrogen conveying pipe 17, the second liquid air conveying pipe 16, the waste nitrogen conveying pipe 19 and the finished nitrogen conveying pipe 20. A third regulating valve 22 is provided on the first liquid nitrogen conveying pipe 17, the second liquid nitrogen conveying pipe 18, the second liquid air conveying pipe 16, the waste nitrogen conveying pipe 19 and the finished nitrogen conveying pipe 20 respectively. The oxygen main pipe 10, waste nitrogen pipe 19, finished nitrogen pipe 20, and raw material air main pipe 1 on the side of the first oxygen delivery branch pipe 11 away from the upper tower 3 are installed on the main heat exchanger 2. The waste nitrogen pipe 19 between the main heat exchanger 2 and the upper tower 3, the finished nitrogen pipe 20 between the main heat exchanger 2 and the upper tower 3, the first liquid nitrogen pipe 17 between the second liquid nitrogen pipe 18 and the upper tower 3, and the second liquid air pipe 16 are installed on the subcooler 21. A first liquid oxygen delivery pipe 24 is provided between the liquid oxygen evaporator 7 and the liquid oxygen storage tank 9, and a second liquid oxygen delivery pipe 25 is provided between the condenser evaporator 4 and the liquid oxygen storage tank 9. A fourth regulating valve 26 is provided on both the second liquid oxygen delivery pipe 25 and the first liquid oxygen delivery pipe 24.

[0019] Both the bottom of the lower tower 5 and the bottom of the cold source channel of the condenser evaporator 4 are provided with a discharge pipe 37, and a shut-off valve 38 is provided on the discharge pipe 37.

[0020] Liquid level sensors 23 are installed on the cold source channels of the liquid air storage tank 6, liquid oxygen storage tank 9, and liquid oxygen evaporator 7; the installation of liquid level sensors 23 facilitates feedback of liquid level height.

[0021] The top of the liquid air storage tank 6 is equipped with a first pressure relief valve 27. Installing the first pressure relief valve 27 facilitates gas release, thereby maintaining the safe operation of the liquid air storage tank 6. The first oxygen delivery branch pipe 11, along the direction of the liquid oxygen evaporator 7 and the main oxygen delivery pipe 10, is sequentially equipped with the outlet end of a pressure relief pipe 28, a second pressure relief valve 29, and a pressure sensor 30. Installing the pressure sensor 30 facilitates feedback of pressure parameters within the first oxygen delivery branch pipe 11, and the second pressure relief valve 29 facilitates the release of overpressure gas within the first oxygen delivery branch pipe 11, thereby maintaining the first... The oxygen delivery branch pipe 11 is safe to use; the inlet end of the pressure relief pipe 28 is connected to the top of the liquid oxygen storage tank 9, and a self-regulating valve 31 is installed on the pressure relief pipe 28; the self-regulating valve 31 includes a regulating valve body and a pressure tapping pipe, and the pressure relief pipe 28 between the regulating valve body and the liquid oxygen storage tank 9 and the pressure tapping pipe are connected, so that when the pressure of the upper layer of liquid in the liquid oxygen storage tank 9 exceeds the preset value, the regulating valve body opens to release the excess gas, so that the pressure of the upper layer of liquid in the liquid oxygen storage tank 9 is maintained within a suitable range.

[0022] If the sum of the oxygen flow rate produced after distillation in the upper column 3 and the oxygen flow rate produced by the vaporization of liquid oxygen in the cold source channel of the condenser evaporator 4 still cannot meet the user's needs, this product provides an outlet end of a second oxygen delivery branch pipe 32 on the first oxygen delivery branch pipe 11 between the outlet end of the pressure relief pipe 28 and the liquid oxygen evaporator 7. The inlet end of the second oxygen delivery branch pipe 32 is connected to the liquid oxygen storage tank 9. The second oxygen delivery branch pipe 32 is provided with a fifth regulating valve 33, a cold source channel of the air-cooled heat exchanger 34 and a first one-way valve 35 in sequence along the direction from near the liquid oxygen storage tank 9 to far away from the liquid oxygen storage tank 9. A second one-way valve 36 is provided between the second oxygen delivery branch pipe 32 and the liquid oxygen evaporator 7. By transporting the liquid oxygen stored in the liquid oxygen storage tank 9 to the cold source channel of the air-cooled heat exchanger 34 and exchanging heat with the air outside the air-cooled heat exchanger 34, the liquid oxygen passing through the cold source channel of the air-cooled heat exchanger 34 is vaporized to form oxygen, which is then transported to the oxygen transmission main pipe 10 through the first oxygen transmission branch pipe 11 and discharged together with the oxygen transported through the oxygen transmission main pipe 10.

[0023] The usage instructions for this product are as follows: Figure 1 As shown, it includes the following steps:

[0024] S1. The compressed air supplied by the purification system continuously supplies compressed air to the raw material air supply main pipe 1. The compressed air entering the raw material air supply main pipe 1 first enters the first heat source channel of the main heat exchanger 2 and exchanges heat with the cold source medium continuously supplied to the main heat exchanger 2. Then it is divided into three parts, namely the first part of compressed air, the second part of compressed air and the third part of compressed air. The first part of compressed air is supplied to the upper column 3 as the gaseous distillation feedstock of the upper column 3. The second part of compressed air is supplied to the lower column 5 as the gaseous distillation feedstock of the lower column 5. The third part of compressed air is supplied to the liquid oxygen evaporator 7, and after exchanging heat with the medium in the heat source channel and the cold source channel of the liquid oxygen evaporator 7, it forms liquid air and is supplied to the liquid air storage tank 6 for temporary storage. The liquid air in the liquid air storage tank 6 is supplied to the upper column 3 through the first liquid air supply pipe 8 as one of the liquid distillation feedstocks of the upper column 3.

[0025] The second part of compressed air is delivered to the lower tower 5 to form a first upward airflow. The first upward airflow continues to rise along the lower tower 5 and continuously exchanges heat with the first condensate reflux liquid that continues to flow downward along the inner cavity of the lower tower 5. Finally, a first nitrogen enrichment zone is formed at the top of the lower tower 5 and an oxygen-rich liquid air enrichment zone is formed at the bottom of the lower tower 5. The first nitrogen enrichment zone continuously supplies the first nitrogen to the heat source channel of the condenser evaporator 4. After heat exchange with the medium in the cold source channel of the condenser evaporator 4, the first nitrogen is liquefied to form liquid nitrogen. The liquid nitrogen delivered outward from the heat source channel of the condenser evaporator 4 is divided into two parts, namely the first part of liquid nitrogen and the second part of liquid nitrogen. The first part of liquid nitrogen is delivered to the lower tower 5 through the second liquid nitrogen delivery pipe 18 as the first condensate reflux liquid of the lower tower 5. The second part of liquid nitrogen is delivered to the first liquid nitrogen delivery pipe 17, passes through the first heat source channel of the cooler 21, and exchanges heat with the cold source continuously supplied to the subcooler 21 to form subcooled liquid nitrogen, which is then delivered to the upper tower 3 as the second reflux condensate liquid of the upper tower 3. The oxygen-rich liquid air enrichment zone continuously passes through the second liquid air delivery pipe 16, through the second heat source channel of the cooler 21, and through the cold source continuously supplied to the subcooler 21 to exchange heat and form subcooled oxygen-rich liquid air, which is then delivered to the upper column 3 as one of the gaseous distillation feedstocks of the upper column 3.

[0026] After the first portion of compressed air enters the inner cavity of the upper tower 3, it forms a second rising airflow. The second rising airflow continues to rise along the inner cavity of the upper tower 3, first being delivered to the upper tower 3 by the second liquid air delivery pipe 16 and then undergoing countercurrent heat exchange with the subcooled oxygen-enriched liquid air that continues to descend along the upper tower 3. It then undergoes countercurrent heat exchange with the liquid air delivered to the upper tower 3 by the first liquid air delivery pipe 8, and finally undergoes countercurrent heat exchange with the second reflux condensate that continues to descend along the inner cavity of the upper tower 3. Ultimately, a second nitrogen enrichment zone is formed at the top of the upper tower 3, a liquid oxygen enrichment zone is formed in the cold source channel of the condenser-evaporator 4, and an oxygen enrichment zone is formed at the bottom of the upper tower 3.

[0027] The area below the second nitrogen enrichment zone continuously supplies waste nitrogen to the waste nitrogen delivery pipe 19. The waste nitrogen first exchanges heat through the first cold source channel of the cooler 21 and the heat source continuously supplied to the subcooler 21, then exchanges heat through the first cold source channel of the main heat exchanger 2 and the heat source continuously supplied to the main heat exchanger 2 before being delivered to the target user of the waste nitrogen. The second nitrogen enrichment zone continuously supplies finished nitrogen to the finished nitrogen delivery pipe 20. The finished nitrogen first exchanges heat through the second cold source channel of the cooler 21 and the heat source continuously supplied to the subcooler 21, then exchanges heat through the second cold source channel of the main heat exchanger 2 and the heat source continuously supplied to the main heat exchanger 2 before being delivered to the target user of the nitrogen. The oxygen enrichment zone continuously supplies finished oxygen to the oxygen delivery main pipe 10, exchanges heat through the third cold source channel of the main heat exchanger 2 and the heat source continuously supplied to the main heat exchanger 2 before being delivered to the target user of the oxygen. The liquid oxygen enrichment zone continuously supplies liquid oxygen to the liquid oxygen storage tank 9 via the second liquid oxygen delivery pipe 25, where it is stored.

[0028] After completing step S1, if the blast furnace is in a stopped state, proceed to step S2-1; if the blast furnace is in a started state, proceed to step S2-2.

[0029] S2-1. Maintain the supply of the second part of compressed air unchanged, thereby stabilizing the distillation state of the lower column 5. Increase the supply of the first part of compressed air and decrease the supply of the third part of compressed air, thereby reducing the medium supplied to the heat source channel of the liquid oxygen evaporator 7 and thus reducing the liquid air supplied to the liquid air storage tank 6. Correspondingly, the flow rate of liquid air supplied from the liquid air storage tank 6 to the upper column 3 is also reduced. Adjust the opening of the first regulating valve 13 installed on the raw material air supply main pipe 1 to maintain the flow rate of finished oxygen supplied from the upper column 3 to the oxygen supply main pipe 10. At the same time, adjust the opening of the fourth regulating valve 26 installed on the second liquid oxygen supply pipe 25 to increase the flow rate of liquid oxygen supplied from the liquid oxygen enrichment zone to the outside, and store it in the liquid oxygen storage tank 9.

[0030] S2-2. Maintaining the flow rate of the second portion of compressed air constant, thereby stabilizing the distillation state of the lower column 5, reducing the flow rate of the first portion of compressed air and increasing the flow rate of the third portion of compressed air, thereby increasing the medium supplied to the heat source channel of the liquid oxygen evaporator 7 and thus increasing the liquid air supplied to the liquid air storage tank 6; during this period, the liquid oxygen storage tank 9 should promptly replenish liquid oxygen to the cold source channel of the liquid oxygen evaporator 7, thereby maintaining the liquid level height of the cold source channel of the liquid oxygen evaporator 7, and the liquid oxygen in the cold source channel of the liquid oxygen evaporator 7 is exchanged with the third portion of compressed air. The oxygen vaporized after heating forms the first supplementary oxygen. During this period, it is still necessary to readjust the opening of the first regulating valve 13 installed on the raw material air conveying main 1 and the opening of the fourth regulating valve 26 installed on the second liquid oxygen conveying pipe 25, so as to keep the flow rate of finished oxygen conveyed from the upper tower 3 to the oxygen conveying main 10 unchanged and reduce the flow rate of liquid oxygen conveyed from the liquid oxygen enrichment zone. The first supplementary oxygen is conveyed to the oxygen conveying main 10 through the first oxygen conveying branch pipe 11 and merged with the finished oxygen in the oxygen conveying main 10 before being conveyed to the target user of oxygen through the outlet end of the oxygen conveying main 10.

[0031] If, after executing step S2-2, the flow rate of finished oxygen delivered through the oxygen main pipe 10 still cannot meet the customer's needs, then step S2-3 should be executed based on step S2-2, as follows:

[0032] S2-3. The liquid oxygen storage tank 9 continuously supplies a portion of liquid oxygen to the second oxygen delivery branch pipe 32. The liquid oxygen entering the second oxygen delivery branch pipe 32 is delivered to the cold source channel of the air-cooled heat exchanger 34 and exchanged with the atmosphere outside the air-cooled heat exchanger 34, thereby being vaporized to form the second supplementary oxygen. The second supplementary nitrogen is then delivered to the first oxygen delivery branch pipe 11 and combined with the first supplementary oxygen delivered in the first oxygen delivery branch pipe 11. After being delivered to the oxygen delivery main pipe 10, it is combined with the finished oxygen in the oxygen delivery main pipe 10 and then delivered to the target user of oxygen through the outlet end of the oxygen delivery main pipe 10.

[0033] In this embodiment, since the total amount of raw air supplied to the upstream raw air supply main 1 is not adjusted, it is not necessary to adjust the load of the upstream air separation precooling system and air compressor unit of the distillation system. This ensures that the raw air supply main 1 receives raw air with continuously stable process parameters. Furthermore, it is not necessary to adjust the flow rate of compressed air supplied to the lower column 5, thus ensuring that the distillation process in the lower column 5 remains stable. Consequently, even when the blast furnace is shut down, sufficient liquid distillation feedstock and subcooled liquid nitrogen can be continuously supplied to the upper column 3. This allows the upper column 3 to benefit from the increased supply of raw air from the raw air supply main 1. Based on the compressed air supplied by 1, sufficient cooling capacity can be obtained to produce liquid oxygen and deliver it to the liquid oxygen storage tank 9 for temporary storage. When the blast furnace is in the open state, the amount of compressed air supplied by the raw material air supply main pipe 1 is reduced, which further reduces the amount of liquid oxygen produced. While keeping the flow rate of finished oxygen supplied by the upper tower 3 to the oxygen supply main pipe 10 unchanged, the additional oxygen required due to the blast furnace is provided by the oxygen vaporized by heat exchange in the cold source channel of the liquid oxygen evaporator 7 and the vaporized oxygen in the cold source channel of the air-cooled heat exchanger 34 supplied by the liquid oxygen storage tank 9, thereby reducing the range of process adjustments of the cryogenic distillation system equipment.

[0034] The embodiments described above are merely preferred embodiments of this utility model and are not intended to limit the scope of implementation of this utility model. Therefore, all equivalent changes or modifications made to the structure, features and principles described in the patent claims of this utility model should be included within the scope of the patent application of this utility model.

Claims

1. A variable load oxygen supply device, comprising a distillation column, a raw material air conveying main (1), and a main heat exchanger (2) for gas heat exchange, wherein the distillation column comprises, from top to bottom, an upper column (3), a condenser-evaporator (4), and a lower column (5), characterized in that: The upper tower (3) is connected to a liquid air storage tank (6). The inlet end of the liquid air storage tank (6) is connected to the outlet end of the heat source channel of the liquid oxygen evaporator (7). A first liquid air delivery pipe (8) is provided at the bottom end of the liquid air storage tank (6) and on the upper tower (3). A liquid oxygen storage tank (9) is connected to the cold source channel of the liquid oxygen evaporator (7). The liquid oxygen storage tank (9) and the cold source channel of the condenser evaporator (4) are connected. An oxygen delivery main pipe (10) is provided on the upper tower (3). A first oxygen delivery branch pipe (1) is provided between the cold source channel of the liquid oxygen evaporator (7) and the oxygen delivery main pipe (10). 1) A raw material air delivery branch pipe (12) is provided between the upper tower (3) and the raw material air delivery main pipe (1), between the raw material air delivery main pipe (1) and the lower tower (5), and between the raw material air delivery main pipe (1) and the inlet end of the heat source channel of the liquid oxygen evaporator (7). A first regulating valve (13) is provided on the raw material air delivery main pipe (1) between the first oxygen delivery branch pipe (11) and the upper tower (3) and on each raw material air delivery branch pipe (12). A second regulating valve (14) and a booster pump (15) are provided on the first liquid air delivery pipe (8).

2. The variable load oxygen supply device according to claim 1, characterized in that: The upper tower (3) and the lower tower (5) are provided with a second liquid air conveying pipe (16). The top of the upper tower (3) is connected to the inlet end of the heat source channel of the condenser evaporator (4). A first liquid nitrogen conveying pipe (17) is provided between the outlet end of the heat source channel of the condenser evaporator (4) and the upper tower (3). A second liquid nitrogen conveying pipe (18) is provided between the outlet end of the heat source channel of the condenser evaporator (4) and the lower tower (5). A waste nitrogen conveying pipe (19) and a finished nitrogen conveying pipe (20) are provided on the upper tower (3). An overcooler (21) is provided on the first liquid nitrogen conveying pipe (17), the second liquid air conveying pipe (16), the waste nitrogen conveying pipe (19), and the finished nitrogen conveying pipe (20). A third regulating valve (22) is provided on the first liquid nitrogen conveying pipe (17), the second liquid nitrogen conveying pipe (18), the second liquid air conveying pipe (16), the waste nitrogen conveying pipe (19), and the finished nitrogen conveying pipe (20).

3. The variable load oxygen supply device according to claim 1, characterized in that: Liquid level sensors (23) are installed on the cold source channels of the liquid air storage tank (6), liquid oxygen storage tank (9) and liquid oxygen evaporator (7).

4. The variable load oxygen supply device according to claim 1, characterized in that: A first liquid oxygen delivery pipe (24) is provided between the liquid oxygen evaporator (7) and the liquid oxygen storage tank (9), and a second liquid oxygen delivery pipe (25) is provided between the condenser evaporator (4) and the liquid oxygen storage tank (9). A fourth regulating valve (26) is provided on both the second liquid oxygen delivery pipe (25) and the first liquid oxygen delivery pipe (24).

5. The variable load oxygen supply device according to claim 1, characterized in that: The liquid air storage tank (6) is provided with a first pressure relief valve (27) at the top. The first oxygen delivery branch pipe (11) is provided with the outlet end of the pressure relief pipe (28), the second pressure relief valve (29) and the pressure sensor (30) in sequence along the direction of the liquid oxygen evaporator (7) and the oxygen delivery main pipe (10). The inlet end of the pressure relief pipe (28) is connected to the top of the liquid oxygen storage tank (9). The pressure relief pipe (28) is provided with a self-regulating valve (31).

6. The variable load oxygen supply device according to claim 5, characterized in that: The outlet end of the pressure relief pipe (28) and the first oxygen delivery branch pipe (11) between the outlet end of the pressure relief pipe (28) and the liquid oxygen evaporator (7) are provided with the outlet end of the second oxygen delivery branch pipe (32). The inlet end of the second oxygen delivery branch pipe (32) is connected to the liquid oxygen storage tank (9). The second oxygen delivery branch pipe (32) is provided with a fifth regulating valve (33), a cold source channel of the air-cooled heat exchanger (34) and a first one-way valve (35) in sequence along the direction from near the liquid oxygen storage tank (9) to far away from the liquid oxygen storage tank (9). A second one-way valve (36) is provided between the second oxygen delivery branch pipe (32) and the liquid oxygen evaporator (7).

7. The variable load oxygen supply device according to claim 1, characterized in that: The bottom of the lower tower (5) and the bottom of the cold source channel of the condenser evaporator (4) are respectively provided with a discharge pipe (37) and a shut-off valve (38) is provided on the discharge pipe (37).

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