Liquid pump precooling liquid oxygen recovery device

Abstract

The utility model provides a liquid pump precooling liquid oxygen recovery device, which belongs to the technical field of liquid oxygen recovery and comprises a liquid oxygen storage tank, a liquid pump, an intermediate separation tank, a heat exchanger and an intermediate buffer tank. The inflow end of the liquid pump is communicated with the outflow port of the liquid oxygen storage tank; the liquid pump is provided with a working outlet and a precooling outlet; the inflow end of the middle separation tank is communicated with the precooling outlet; the top of the middle separation tank is provided with a first exhaust port, and the bottom is provided with a liquid oxygen reflux inlet; a liquid oxygen outlet is formed in the bottom of the heat exchanger; an oxygen channel and a refrigerant channel are arranged in the heat exchanger, and the oxygen channel communicates with the oxygen inlet and the liquid oxygen outlet. The flow inlet end of the middle buffer tank is respectively communicated with the liquid oxygen outlet and the liquid oxygen reflux inlet; and the outflow end of the middle buffer tank is communicated with the inflow end of the liquid pump. The pre-cooling liquid oxygen recovery device for the liquid pump can eliminate potential safety hazards, improve the repeated utilization rate of oxygen and liquid oxygen and avoid resource waste.

Description

Technical Field

[0001] The utility model belongs to the technical field of liquid oxygen recovery, and more specifically relates to a liquid pump precooling liquid oxygen recovery device. Background Art

[0002] In the oxygen production system of steel enterprises, it is often necessary to transport the cryogenic liquid in the liquid storage tank in stages. Among them, the centrifugal cryogenic liquid pump is often used to transport cryogenic liquid oxygen. However, the liquid pump needs to be pre-cooled with liquid oxygen before starting to prevent the liquid oxygen from cavitating the liquid pump after gasification, causing damage to the liquid pump.

[0003] After the liquid pump is pre-cooled with liquid oxygen, the liquid oxygen is converted into a mixed gas-liquid of oxygen and liquid oxygen. If the mixed gas-liquid is discharged directly, the liquid oxygen will gather in low-lying areas and easily explode when encountering open flames, posing a safety hazard. In the prior art, liquid oxygen needs to be completely converted into a gaseous state through heat exchange before being discharged. Although this can reduce safety hazards, it will also cause a waste of resources. Utility Model Content

[0004] The utility model aims to provide a liquid pump precooling liquid oxygen recovery device, aiming to solve the technical problems of potential safety hazards and resource waste when discharging the liquid oxygen mixed gas and liquid formed after the liquid pump is precooled.

[0005] In order to achieve the above-mentioned purpose, the technical solution adopted by the utility model is: to provide a liquid pump precooling liquid oxygen recovery device, comprising:

[0006] a liquid oxygen storage tank having an outlet;

[0007] A liquid pump, the inlet end of which is connected to the outlet; the liquid pump has a working outlet for outputting liquid oxygen, and a precooling outlet for outputting a mixed gas and liquid;

[0008] An intermediate separation tank, the inlet end of which is connected to the pre-cooling outlet; a first exhaust port is provided at the top of the intermediate separation tank, and a liquid oxygen reflux port is provided at the bottom;

[0009] A heat exchanger having an oxygen inlet at the top and a liquid oxygen outlet at the bottom; an oxygen channel and a refrigerant channel for heat exchange with the oxygen channel are provided inside the heat exchanger, the oxygen channel is connected to the oxygen inlet and the liquid oxygen outlet respectively; the oxygen inlet is connected to the first exhaust port; and

[0010] The intermediate buffer tank has an inlet end connected to the liquid oxygen outlet and the liquid oxygen reflux port respectively; and an outlet end of the intermediate buffer tank is connected to an inlet end of the liquid pump.

[0011] In a possible implementation, a connecting pipe is provided at the inlet end of the intermediate separation tank, one end of the connecting pipe extends into the intermediate separation tank and is connected to a guide pipe, one end of the guide pipe is connected to the liquid oxygen reflux port; and an air guide groove opening upward is provided on the guide pipe.

[0012] In some embodiments, the guide pipe is in a spiral or a curved shape and extends downward to the liquid oxygen reflux port, and the air guide groove extends downward along the guide pipe to the liquid oxygen reflux port.

[0013] In a possible implementation, the inlet end of the intermediate separation tank is connected to the precooling outlet via a first pipeline, and a first control valve is provided on the first pipeline.

[0014] In some embodiments, a second pipeline is connected between the precooling outlet and the oxygen inlet, and a second control valve is provided on the second pipeline.

[0015] In a possible implementation, a second exhaust port is provided on the top of the intermediate buffer tank.

[0016] In some embodiments, the second exhaust port is connected to the inlet end of the intermediate separation tank via a third pipeline, and a third control valve is provided on the third pipeline.

[0017] In a possible implementation, a third exhaust port is provided on the top of the liquid oxygen storage tank; the third exhaust port is connected to the oxygen inlet via a fourth pipeline, and a fourth control valve is provided on the fourth pipeline.

[0018] In some embodiments, a fourth exhaust port is provided on the top of the liquid oxygen storage tank; the fourth exhaust port is connected to the inlet end of the intermediate separation tank through a fifth pipeline, and a fifth control valve is provided on the fifth pipeline.

[0019] In a possible implementation, the inlet end of the refrigerant channel is connected to a liquid nitrogen delivery pump, and the outlet end of the refrigerant channel is connected to a nitrogen recovery tank.

[0020] Compared with the prior art, the scheme shown in the embodiment of the present application can pre-cool the liquid pump with the low-temperature liquid oxygen in the liquid oxygen storage tank, and transport the mixed gas-liquid formed after the pre-cooling of the liquid pump to the intermediate separation tank for preliminary gas-liquid separation, so that the liquid oxygen can flow back to the intermediate buffer tank through the liquid oxygen reflux port for storage, and the oxygen can be transported to the heat exchanger for cooling and heat exchange, thereby converting the oxygen into liquid oxygen in a low-temperature state and storing it in the intermediate buffer tank to prepare for the next pre-cooling of the liquid pump or transportation to the next process procedure; the liquid pump pre-cooling liquid oxygen recovery device provided in the present application can eliminate the safety hazards when oxygen is directly discharged, and improve the reuse rate of oxygen and liquid oxygen to avoid waste of resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments 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.

[0022] Figure 1 A schematic diagram of the structure of a liquid pump precooling liquid oxygen recovery device provided in an embodiment of the utility model;

[0023] Figure 2 A schematic cross-sectional structure diagram of an intermediate separation tank provided in an embodiment of the utility model.

[0024] In the figure:

[0025] 1. Liquid oxygen storage tank; 11. Outlet; 12. Third exhaust port; 13. Fourth pipeline; 131. Fourth control valve; 2. Liquid pump; 21. Working outlet; 22. Precooling outlet; 3. Intermediate separation tank; 31. First exhaust port; 32. Liquid oxygen reflux port; 33. Connecting pipe; 34. Flow guide pipe; 341. Gas guide groove; 4. Heat exchanger; 41. Oxygen inlet; 42. Liquid oxygen outlet; 5. Intermediate buffer tank; 51. Second exhaust port; 52. Third pipeline; 521. Third control valve; 6. First pipeline; 61. First control valve; 7. Second pipeline; 71. Second control valve; 8. Liquid nitrogen delivery pump; 9. Nitrogen recovery tank. DETAILED DESCRIPTION

[0026] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0027] It should be noted that when an element is referred to as being "disposed on" another element, it may be directly on the other element or indirectly on the other element. It should be understood that the terms "length", "width", "upper", "lower", "front", "back", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0028] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "several" is two or more, unless otherwise clearly and specifically defined.

[0029] Please also read Figure 1 and Figure 2 Now, the liquid pump 2 precooling liquid oxygen recovery device provided by the utility model is described. The liquid pump 2 precooling liquid oxygen recovery device comprises a liquid oxygen storage tank 1, a liquid pump 2, an intermediate separation tank 3, a heat exchanger 4 and an intermediate buffer tank 5; the liquid oxygen storage tank 1 has an outlet 11; the inlet end of the liquid pump 2 is connected to the outlet 11; the liquid pump 2 has a working outlet 21 for outputting liquid oxygen, and a precooling outlet 22 for outputting a mixed gas and liquid; the inlet end of the intermediate separation tank 3 is connected to the precooling outlet 22; the top of the intermediate separation tank 3 is provided with a first exhaust port 31, and the bottom is provided with a liquid oxygen reflux port 32; the top of the heat exchanger 4 is provided with an oxygen inlet 41, and the bottom is provided with a liquid oxygen outlet 42; the inside of the heat exchanger 4 is provided with an oxygen channel and a refrigerant channel for heat exchange with the oxygen channel, and the oxygen channel is respectively connected to the oxygen inlet 41 and the liquid oxygen outlet 42; the oxygen inlet 41 is connected to the first exhaust port 31; the inlet end of the intermediate buffer tank 5 is respectively connected to the liquid oxygen outlet 42 and the liquid oxygen reflux port 32; the outlet end of the intermediate buffer tank 5 is connected to the inlet end of the liquid pump 2.

[0030] It should be understood that the liquid oxygen storage tank 1 is used to store liquid oxygen, and the liquid oxygen is often transported from the liquid oxygen storage tank 1 to the next process or other required user end through the working outlet 21 of the liquid pump 2; after the liquid pump 2 is precooled by low-temperature liquid oxygen, the low-temperature liquid oxygen is converted into a mixed gas-liquid of liquid oxygen and oxygen, and is transported to the intermediate separation tank 3 through the precooling outlet 22 of the liquid pump 2.

[0031] The mixed gas and liquid entering the intermediate separation tank 3 are initially separated to form a small amount of liquid oxygen flow and secondary gas and liquid with less liquid content. The small amount of liquid oxygen flow is transported to the intermediate buffer tank 5 for storage through the liquid oxygen reflux port 32 of the intermediate separation tank 3, and the secondary gas and liquid with less liquid content is transported to the heat exchanger 4 for heat exchange with the refrigerant medium to liquefy and form liquid oxygen, and the liquid oxygen formed after the heat exchange is transported to the intermediate buffer tank 5 for storage.

[0032] By setting the intermediate separation tank 3, the mixed gas and liquid can be initially separated to prevent a small amount of liquid oxygen from entering the heat exchanger 4 to increase the workload of the heat exchanger 4, and at the same time improve the recovery efficiency of the device.

[0033] Optionally, a pressure detection device and a temperature detection device are provided on the connecting pipe 33 between the liquid oxygen reflux port 32 and the intermediate buffer tank 5 to monitor the pressure and temperature of the refluxed liquid oxygen in real time.

[0034] Compared with the prior art, the liquid pump 2 precooling liquid oxygen recovery device provided by the utility model can precool the liquid pump 2 through the low-temperature liquid oxygen in the liquid oxygen storage tank 1, and transport the mixed gas and liquid formed after the precooling of the liquid pump 2 to the intermediate separation tank 3 for preliminary gas-liquid separation, so that the liquid oxygen can flow back to the intermediate buffer tank 5 through the liquid oxygen reflux port 32 for storage, and the oxygen is transported to the heat exchanger 4 for cooling and heat exchange, thereby converting the oxygen into liquid oxygen in a low-temperature state and storing it in the intermediate buffer tank 5, so as to prepare for the next precooling of the liquid pump 2 or transport to the next process procedure; the liquid pump 2 precooling liquid oxygen recovery device provided in the present application can eliminate the safety hazards when oxygen is directly discharged, and improve the reuse rate of oxygen and liquid oxygen to avoid waste of resources.

[0035] See also Figure 2 In some possible embodiments, a connecting pipe 33 is provided at the inlet end of the intermediate separation tank 3, one end of the connecting pipe 33 extends into the intermediate separation tank 3 and is connected to a guide pipe 34, one end of the guide pipe 34 is connected to the liquid oxygen reflux port 32; and a gas guide groove 341 with an opening facing upward is provided on the guide pipe 34.

[0036] The guide pipe 34 is provided so that the mixed gas and liquid flow downward along the guide pipe 34 , and the gas guide groove 341 is provided so that the gaseous oxygen can be separated from the mixed gas and liquid and transported to the heat exchanger 4 through the first exhaust port 31 at the top for heat exchange.

[0037] See also Figure 2 In some embodiments, the guide pipe 34 is spirally or bent and extends downward to the liquid oxygen reflux port 32 , and the air guide groove 341 extends downward along the guide pipe 34 to the liquid oxygen reflux port 32 .

[0038] By configuring the flow guide tube 34 to be spiral or bent and winding, the flow path of the mixed gas and liquid in the flow guide tube 34 is extended, so that the gas component in the mixed gas and liquid is fully separated, thereby avoiding residual gas in the liquid oxygen.

[0039] It should be noted that the appendix in this application Figure 2 The above is only one specific embodiment of the bending and winding of the above-mentioned guide tube 34. The guide tube 34 can also be a spiral winding shape such as a spring structure, or other bending and winding structures that can extend the flow path of the guide tube 34. In addition, the air guide groove 341 also has a corresponding spiral shape or a bending and winding shape along the axis of the guide tube 34.

[0040] It should be understood that the mixed gas and liquid formed during precooling of the liquid pump 2 is often output in stages, and if the amount of mixed gas and liquid output each time is not large, if it directly enters the heat exchanger 4 for heat exchange, it is necessary to frequently start the heat exchanger 4 and input the refrigerant medium in real time, which will increase the consumption cost of the heat exchanger 4. In the present application, an intermediate separation tank 3 is provided to initially cache the mixed gas and liquid, and after the mixed gas and liquid accumulate to a preset value, the heat exchanger 4 is opened to heat the mixed gas and liquid accumulated multiple times, and at the same time, the retention time of the moderated gas and liquid in the intermediate separation tank 3 is extended to promote gas-liquid separation.

[0041] See also Figure 1 As a method of conveying the mixed gas and liquid, the inlet end of the intermediate separation tank 3 is connected to the precooling outlet 22 through a first pipeline 6, and a first control valve 61 is provided on the first pipeline 6.

[0042] The first pipeline 6 is provided so as to transport the mixed gas and liquid discharged from the pre-cooling outlet 22 to the intermediate separation tank 3 , and the on-off of the first pipeline 6 is controlled by the first control valve 61 .

[0043] See also Figure 1 As another method of conveying the mixed gas and liquid, a second pipeline 7 is connected between the precooling outlet 22 and the oxygen inlet 41 , and a second control valve 71 is provided on the second pipeline 7 .

[0044] Taking into account that when the mixed gas and liquid in the intermediate separation tank 3 accumulates to a preset value and heat exchange is required, the new mixed gas and liquid formed in the liquid pump 2 can no longer be transported to the intermediate separation tank 3, in this application, by setting a second pipeline 7, the mixed gas and liquid can be directly transported to the heat exchanger 4 for heat exchange, so as to recover the mixed gas and liquid formed after pre-cooling of the liquid pump 2 in the above-mentioned emergency situation.

[0045] Specifically, the second control valve 71 is used to control the on-off of the second pipeline 7 .

[0046] See also Figure 1 In some possible embodiments, a second exhaust port 51 is provided on the top of the intermediate buffer tank 5 .

[0047] It should be understood that liquid oxygen is stored in the intermediate buffer tank 5. As a normal pressure storage tank, a small amount of the liquid oxygen inside will be converted into oxygen. In order to balance the pressure in the intermediate buffer tank 5, it is necessary to discharge the excess oxygen regularly to ensure the safety of the intermediate buffer tank 5. The second exhaust port 51 is provided so that the excess oxygen can be discharged from the intermediate buffer tank 5 in time to balance the internal pressure.

[0048] See also Figure 1 In some embodiments, the second exhaust port 51 is connected to the inlet end of the intermediate separation tank 3 through a third pipeline 52 , and a third control valve 521 is provided on the third pipeline 52 .

[0049] In order to avoid the waste of oxygen in the intermediate buffer tank 5, a third pipeline 52 is provided in the present application, which can guide the excess oxygen to the intermediate separation tank 3 for temporary storage, and the oxygen separated from the mixed gas and liquid enters the heat exchanger 4 again for heat exchange to form liquid oxygen, thereby improving the reuse rate of oxygen.

[0050] It should be noted that, as a normal pressure storage tank, a small amount of liquid oxygen in the liquid oxygen storage tank 1 will also be converted into oxygen. In order to balance the pressure in the liquid oxygen storage tank 1, it is necessary to discharge excess oxygen through the third exhaust port 12 or the fourth exhaust port to ensure the safety of the liquid oxygen storage tank 1.

[0051] See also Figure 1 As a specific implementation of the oxygen recovery method in the liquid oxygen storage tank 1, a third exhaust port 12 is provided on the top of the liquid oxygen storage tank 1; the third exhaust port 12 is connected to the oxygen inlet 41 through a fourth pipeline 13, and a fourth control valve 131 is provided on the fourth pipeline 13.

[0052] The third exhaust port 12 is provided to transport excess oxygen to the heat exchanger 4 for direct heat exchange, and to form liquid oxygen again for storage in the intermediate buffer tank 5. The fourth control valve 131 is used to control the on-off of the oxygen flow on the fourth pipeline 13.

[0053] See also Figure 1 As another specific implementation of the oxygen recovery method in the liquid oxygen storage tank 1, a fourth exhaust port is provided on the top of the liquid oxygen storage tank 1; the fourth exhaust port is connected to the inlet end of the intermediate separation tank 3 through a fifth pipeline, and a fifth control valve is provided on the fifth pipeline.

[0054] By setting a fourth exhaust port, excess oxygen can be transported to the intermediate separation tank 3 for storage in advance, and the oxygen separated from the mixed gas and liquid enters the heat exchanger 4 for heat exchange to form liquid oxygen again and store it in the intermediate buffer tank 5. The fourth control valve 131 is used to control the on-off of the oxygen flow on the fourth pipeline 13.

[0055] See also Figure 1 In a possible implementation, the inlet end of the refrigerant channel is connected to a liquid nitrogen delivery pump 8, and the outlet end of the refrigerant channel is connected to a nitrogen recovery tank 9.

[0056] Specifically, liquid nitrogen can be introduced into the refrigerant channel, and heat exchange is performed between the liquid nitrogen and oxygen to convert the oxygen into liquid oxygen; the liquid nitrogen delivery pump 8 is used to deliver the liquid nitrogen component separated by the air separation device to the heat exchanger 4, and the nitrogen recovery tank 9 is used to recover and store the nitrogen formed after the heat exchange.

[0057] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. Liquid pump precooling liquid oxygen recovery device, characterized in that: include: A liquid oxygen storage tank (1) having an outlet (11); A liquid pump (2), the inlet end of which is in communication with the outlet (11); the liquid pump (2) has a working outlet (21) for outputting liquid oxygen, and a precooling outlet (22) for outputting a mixed gas and liquid; An intermediate separation tank (3), the inlet end of which is in communication with the precooling outlet (22); a first exhaust port (31) is provided at the top of the intermediate separation tank (3), and a liquid oxygen reflux port (32) is provided at the bottom; A heat exchanger (4) is provided with an oxygen inlet (41) at the top and a liquid oxygen outlet (42) at the bottom; an oxygen channel and a refrigerant channel for heat exchange with the oxygen channel are provided inside the heat exchanger (4), the oxygen channel is communicated with the oxygen inlet (41) and the liquid oxygen outlet (42) respectively; the oxygen inlet (41) is communicated with the first exhaust port (31); and The intermediate buffer tank (5) has an inlet end which is respectively connected to the liquid oxygen outlet (42) and the liquid oxygen reflux port (32); and an outlet end of the intermediate buffer tank (5) is connected to an inlet end of the liquid pump (2).

2. The liquid pump (2) precooling liquid oxygen recovery device according to claim 1, characterized in that: A connecting pipe (33) is provided at the inlet end of the intermediate separation tank (3), one end of the connecting pipe (33) extends into the intermediate separation tank (3) and is connected to a flow guide pipe (34), one end of the flow guide pipe (34) is communicated with the liquid oxygen reflux port (32); and an air guide groove (341) opening upward is provided on the flow guide pipe (34).

3. The liquid pump (2) precooling liquid oxygen recovery device according to claim 2, characterized in that: The flow guide pipe (34) is in a spiral or bent shape and extends downward to the liquid oxygen return port (32), and the air guide groove (341) extends downward along the flow guide pipe (34) to the liquid oxygen return port (32).

4. The liquid pump (2) precooling liquid oxygen recovery device according to claim 1, characterized in that: The inlet end of the intermediate separation tank (3) is connected to the precooling outlet (22) via a first pipeline (6), and a first control valve (61) is provided on the first pipeline (6).

5. The liquid pump (2) precooling liquid oxygen recovery device according to claim 4, characterized in that: A second pipeline (7) is connected between the precooling outlet (22) and the oxygen inlet (41), and a second control valve (71) is provided on the second pipeline (7).

6. The liquid pump (2) precooling liquid oxygen recovery device according to claim 1, characterized in that: A second exhaust port (51) is provided at the top of the intermediate buffer tank (5).

7. The liquid pump (2) precooling liquid oxygen recovery device according to claim 6, characterized in that: The second exhaust port (51) is connected to the inlet end of the intermediate separation tank (3) via a third pipeline (52), and a third control valve (521) is provided on the third pipeline (52).

8. The liquid pump (2) precooling liquid oxygen recovery device according to claim 1, characterized in that: A third exhaust port (12) is provided on the top of the liquid oxygen storage tank (1); the third exhaust port (12) is connected to the oxygen inlet (41) via a fourth pipeline (13), and a fourth control valve (131) is provided on the fourth pipeline (13).

9. The liquid pump (2) precooling liquid oxygen recovery device according to claim 1, characterized in that: A fourth exhaust port is provided at the top of the liquid oxygen storage tank (1); the fourth exhaust port is connected to the inlet end of the intermediate separation tank (3) via a fifth pipeline, and a fifth control valve is provided on the fifth pipeline.

10. The liquid pump (2) precooling liquid oxygen recovery device according to claim 1, characterized in that: The inlet end of the refrigerant channel is connected to a liquid nitrogen delivery pump (8), and the outlet end of the refrigerant channel is connected to a nitrogen recovery tank (9).

Images