Low-temperature gas cooling capacity recovery system

Abstract

The utility model relates to the technical field of low-temperature gas cold energy recovery, in particular to a low-temperature gas cold energy recovery system which comprises a cold liquid storage tank, heat exchange equipment and a water cooling tower, and a low-temperature gas medium is arranged in the cold liquid storage tank; the heat exchange equipment comprises a medium inlet and a medium outlet communicated with the medium inlet, the medium inlet is communicated with the cold liquid storage tank through a first pipeline, a to-be-cooled liquid medium is arranged in the heat exchange equipment, and the to-be-cooled liquid medium can exchange heat with a low-temperature gas medium to form a cold liquid medium; the water cooling tower communicates with the medium outlet through a second pipeline, and the cold liquid medium is transmitted to the water cooling tower through the second pipeline. According to the technical scheme, the low-temperature gas cooling capacity recovery system can recover the cooling capacity in the low-temperature gas.

Description

Technical Field

[0001] The utility model relates to the technical field of low-temperature gas cooling recovery, in particular to a low-temperature gas cooling recovery system. Background Art

[0002] Liquid oxygen, liquid nitrogen and liquid argon are typical cryogenic liquids. After being prepared in the air separation system of an air separation plant, they are sent to the backup liquid storage system through vacuum insulated pipes to prevent the three cryogenic liquids from vaporizing in large quantities.

[0003] The backup liquid storage system is equipped with multiple cold liquid storage tanks, each of which is used to store a cryogenic liquid. The cold liquid storage tanks are double-layer cylindrical structures. The cryogenic liquid is stored in the inner cylinder, which is made of stainless steel and the outer cylinder is made of carbon steel. The double-layer wall panels are filled with insulating material pearl sand. However, since the boiling points of liquid oxygen, liquid nitrogen, and liquid argon are very low, such as the boiling point of liquid nitrogen is -196°C, even if thermal insulation measures are taken, these cryogenic liquids will still be affected by the environment. There will be gasification phenomenon, and because the cold liquid storage tank is a sealed structure, as the gas in the cylinder increases, the pressure in the cylinder will increase. Therefore, it is necessary to regularly empty the gas to maintain the pressure in the cylinder within a safety threshold. Because the temperature of the cryogenic liquid after vaporization is still at a relatively low temperature, if it is completely emptied, it will cause a waste of cold energy. Therefore, if this part of the cold energy can be recovered and put into the air separation system to cool some production water, the power of the cooling unit in the air separation system can be reduced, and the power consumption can be reduced. Utility Model Content

[0004] The main purpose of the utility model is to provide a low-temperature gas cold energy recovery system, aiming to realize the recovery of cold energy in the low-temperature gas.

[0005] To achieve the above purpose, the low-temperature gas cooling energy recovery system comprises:

[0006] A cold liquid storage tank, wherein a low-temperature gas medium is provided inside the cold liquid storage tank;

[0007] A heat exchange device, the heat exchange device comprising a medium inlet and a medium outlet connected to the medium inlet, the medium inlet being connected to the cold liquid storage tank through a first pipe, the heat exchange device having a liquid medium to be cooled inside, the liquid medium to be cooled being heat exchanged with the low-temperature gas medium to form a cold liquid medium; and

[0008] A water cooling tower is connected to the medium outlet through a second pipe, and the cold liquid medium is transferred to the water cooling tower through the second pipe.

[0009] In one embodiment, the first pipeline is provided with a first regulating valve, and the second pipeline is provided with a second pressure pump.

[0010] In one embodiment, a remote thermometer is provided on the outer peripheral wall of the heat exchange device, and a temperature control valve is further provided on the first pipeline, and the temperature control valve can receive an electrical signal from the remote thermometer.

[0011] In one embodiment, a plurality of on-site thermometers are further provided on the outer peripheral wall of the heat exchange device, and the plurality of on-site thermometers are arranged at intervals along the height direction of the heat exchange device.

[0012] In one embodiment, the heat exchange device is further provided with an on-site liquid level gauge, and the on-site liquid level gauge is provided on the outer peripheral wall of the heat exchange device.

[0013] In one embodiment, the heat exchange device is further provided with a remote liquid level gauge, and the remote liquid level gauge is provided on the outer peripheral wall of the heat exchange device.

[0014] In one embodiment, an overflow pipe is provided on the top of the heat exchange device, and one end of the overflow pipe is connected to the interior of the heat exchange device.

[0015] In one embodiment, the heat exchange device is further provided with a circulation pipeline, both ends of which are connected to the heat exchange device; and the circulation pipeline is provided with a circulation water pump.

[0016] In one embodiment, the heat exchange device is further provided with a pipeline for replenishing the liquid medium to be cooled, and the liquid outlet of the pipeline for replenishing the liquid medium to be cooled is arranged close to the medium inlet.

[0017] In one embodiment, the cold liquid storage tank also includes an exhaust pipe, one end of which is connected to the interior of the cold liquid storage tank; the exhaust pipe is provided with a pressure regulating valve, and the pressure regulating valve can adjust the internal air pressure of the cold liquid storage tank; one end of the first pipe is connected to the exhaust pipe.

[0018] In the technical solution of the utility model, the low-temperature gas cold recovery system includes a cold liquid storage tank, a heat exchange device and a water cooling tower. The cold liquid storage tank is connected to the medium inlet of the heat exchange device through a first pipeline, and the water cooling tower is connected to the medium outlet of the heat exchange device through a second pipeline. In order to absorb the cold of the low-temperature gas medium in the cold liquid storage tank, a liquid medium to be cooled is provided inside the heat exchange device. When the low-temperature gas medium with a lowered temperature contacts the liquid medium with a higher temperature to be cooled, a heat exchange process will occur. The temperature of the liquid medium to be cooled is adsorbed by the low-temperature gas medium and becomes a cold liquid medium, so that the temperature of the cold liquid medium can directly reach the process production conditions. The cold liquid medium is transferred to the water cooling tower through the second pipeline and is used in the production process of other equipment in the air separation plant. The low-temperature gas cold recovery system proposed in the utility model can recover the heat of the low-temperature gas medium formed after the gasification of low-temperature liquids such as liquid oxygen, liquid nitrogen, and liquid argon, improve the efficiency of resource utilization, and effectively reduce the power of the cooling unit in the air separation system and reduce power consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, 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 utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0020] Figure 1 The present invention is a schematic structural diagram of an embodiment of a low-temperature gas cooling recovery system provided by the present invention.

[0021] Description of Figure Numbers:

[0022] 10. Cold liquid storage tank; 101. Low-temperature gas medium; 102. Exhaust pipe; 103. Pressure regulating valve; 20. Heat exchange equipment; 201. First pipe; 202. Liquid medium to be cooled; 203. First regulating valve; 204. Remote thermometer; 205. Temperature control valve; 206. Local liquid level gauge; 207. Overflow pipe; 208. Circulation pipe; 209. Circulation water pump; 210. Liquid medium supplement pipe to be cooled; 30. Water cooling tower; 301. Second pipe; 302. Second pressure pump.

[0023] The realization of the purpose, functional features and advantages of the utility model will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0025] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back...) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0026] In addition, the descriptions of "first", "second", etc. in the present utility model are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the meaning of "and / or" appearing in the full text includes three parallel schemes. Taking "A and / or B" as an example, it includes scheme A, or scheme B, or a scheme that satisfies both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present utility model.

[0027] Please refer to Figure 1 The gas cooling capacity recovery system proposed in the utility model includes:

[0028] A cold liquid storage tank 10, wherein a low temperature gas medium 101 is arranged inside the cold liquid storage tank 10;

[0029] The heat exchange device 20 includes a medium inlet and a medium outlet connected to the medium inlet, the medium inlet is connected to the cold liquid storage tank 10 through a first pipe 201, and a liquid medium 202 to be cooled is arranged inside the heat exchange device 20, and the liquid medium 202 to be cooled can be heat-exchanged with the low-temperature gas medium 101 to form a cold liquid medium; and

[0030] The water cooling tower 30 is connected to the medium outlet through the second pipe 301 , and the cold liquid medium is transferred to the water cooling tower 30 through the second pipe 301 .

[0031] In the technical solution of the utility model, the low-temperature gas cold recovery system includes a cold liquid storage tank 10, a heat exchange device 20 and a water cooling tower 30. The cold liquid storage tank 10 is connected to the medium inlet of the heat exchange device 20 through a first pipe 201, and the water cooling tower 30 is connected to the medium outlet of the heat exchange device 20 through a second pipe 301. In order to absorb the cold of the low-temperature gas medium 101 in the cold liquid storage tank 10, a liquid medium 202 to be cooled is provided inside the heat exchange device 20. When the low-temperature gas medium 101 with a reduced temperature contacts the liquid medium 202 with a higher temperature to be cooled, a heat exchange process occurs. The temperature of the liquid medium 202 to be cooled is adsorbed by the low-temperature gas medium 101 and becomes a cold liquid medium, so that the temperature of the cold liquid medium can directly reach the process production conditions. The cold liquid medium is transferred to the water cooling tower 30 through the second pipe 301 and is used in the production process of other equipment in the air separation plant. The low-temperature gas cooling recovery system proposed in the utility model can recover the heat of the low-temperature gas medium 101 formed after the gasification of low-temperature liquids such as liquid oxygen, liquid nitrogen, and liquid argon, thereby improving the efficiency of resource utilization, and effectively reducing the power of the cooling unit in the air separation system and reducing power consumption.

[0032] The cold liquid storage tank 10 can be used to store low-temperature gas media 101 such as liquid oxygen, liquid nitrogen, and liquid argon. An outlet is provided on the top of the tank, which can be used for direct exhaust and can also be connected to a pipeline to guide the flow to the required equipment. It can be understood that the cold liquid storage tank 10 is a double-layer cylindrical structure, and the low-temperature liquid is stored in the inner cylinder. The inner cylinder is made of stainless steel, and the outer cylinder is made of carbon steel. The insulating material pearl sand is filled between the double-layer wall panels to reduce the threshold of heat absorption by low-temperature gas media 101 such as liquid oxygen, liquid nitrogen, and liquid argon.

[0033] The heat exchange device 20 may be in the shape of a pipe with a certain length or in the shape of a cylinder. In order to improve the fluidity of the medium in the heat exchange device 20, the heat exchange device 20 is preferably in the shape of a pipe. The heat exchange device 20 includes a medium inlet, a cavity, and a medium outlet which are connected in sequence. The medium inlet is connected to the gas outlet of the cold liquid storage tank 10 through a first pipe 201. When the low-temperature gas medium 101 in the cold liquid storage tank 10 reaches the threshold of the safety pressure, the low-temperature gas medium 101 can reach the heat exchange device 20 through the first pipe 201. In order to absorb the cold energy possessed by the low-temperature gas medium 101, The cavity of the heat exchange device 20 is provided with a liquid medium 202 to be cooled. The temperature of the liquid medium 202 to be cooled is higher than the temperature of the low-temperature gas medium 101. When the low-temperature gas medium 101 is transferred to the cavity of the heat exchange device 20, the liquid medium 202 to be cooled undergoes heat exchange with the low-temperature gas medium 101 to form a cold liquid medium. The heat of the liquid medium 202 to be cooled is absorbed by the low-temperature gas medium 101 to reduce its own temperature. Furthermore, the first pipe 201 can extend into the cavity of the heat exchange device 20 and the pipe outlet extends into the liquid surface of the liquid medium 202 to be cooled, thereby improving the heat exchange efficiency.

[0034] The water cooling tower 30 is mainly used to cool the liquid medium flowing into it. The water cooling tower 30 is connected to the medium outlet of the heat exchange device 20 through the second pipe 301. The cold liquid medium flows to the water cooling tower 30 through the second pipe 301, and is further cooled here. It can be understood that the temperature of the cold liquid medium is lower than that of the production water or circulating water used in the air separation plant, which means that the working power of the water cooling tower 30 and the subsequent cooling unit can be reduced, thereby reducing power consumption.

[0035] In one embodiment, if Figure 1 As shown, the first pipeline 201 is provided with a first regulating valve 203 , and the second pipeline 301 is provided with a second pressure pump 302 .

[0036] In this embodiment, a first regulating valve 203 is provided at one end of the first pipeline 201 close to the cold liquid storage tank 10, and a second pressure pump 302 is provided at one end of the second pipeline 301 close to the heat exchange device 20. The first regulating valve 203 is mainly used to adjust the flow rate of the low-temperature gas medium 101, and the second pressure pump 302 is mainly used to pressurize the cold liquid medium and increase the speed of the cold liquid medium flowing to the water cooling tower 30, thereby improving the heat exchange efficiency of the low-temperature gas cold recovery system and preventing cold loss.

[0037] In one embodiment, if Figure 1 As shown, a remote thermometer 204 is disposed on the outer peripheral wall of the heat exchange device 20 , and a temperature control valve 205 is also disposed on the first pipeline 201 . The temperature control valve 205 can receive an electrical signal from the remote thermometer 204 .

[0038] In this embodiment, a remote thermometer 204 is provided on the outer wall of the heat exchange device 20, and a temperature control valve 205 is also provided on the first pipeline 201. The remote thermometer 204 can convert the temperature signal into an electrical signal and send it to the temperature control valve 205. The temperature control valve 205 adjusts the flow rate of the low-temperature gas medium 101 flowing through the valve according to the received electrical signal, thereby realizing automatic control of the temperature of the cold liquid medium, so that the temperature of the cold liquid medium flowing to the water cooling tower 30 is within the required temperature range.

[0039] In one embodiment, if Figure 1 As shown, the outer peripheral wall of the heat exchange device 20 is also provided with a plurality of on-site thermometers, and the plurality of on-site thermometers are arranged at intervals along the height direction of the heat exchange device 20 .

[0040] In this embodiment, the outer wall of the heat exchange device 20 is also provided with a plurality of local thermometers, which are used to check the temperature of the cold liquid medium in the heat exchange device 20 in real time and to prevent problems with the remote thermometer 204, so that human intervention can be made to start and stop the low-temperature gas cooling recovery system; further, the plurality of local thermometers are arranged at intervals along the height direction of the heat exchange device 20, because the temperature of the cold liquid medium in different parts of the heat exchange device 20 may be different, and setting a plurality of local thermometers can help identify the local heat exchange conditions.

[0041] In one embodiment, if Figure 1 As shown, the heat exchange device 20 is also provided with an on-site liquid level meter 206 , and the on-site liquid level meter 206 is provided on the outer peripheral wall of the heat exchange device 20 .

[0042] In this embodiment, the heat exchange device 20 is also provided with an on-site liquid level meter 206, which is arranged on the outer wall of the heat exchange device 20. Specifically, the two ends of the on-site liquid level meter 206 are respectively arranged at the two end liquid levels of the heat exchange device 20, so as to check the liquid level of the heat exchange device 20 in real time, thereby controlling the volume of the liquid medium 202 to be cooled in the heat exchange device 20.

[0043] In one embodiment, if Figure 1 As shown, the heat exchange device 20 is also provided with a remote liquid level gauge, which is arranged on the outer peripheral wall of the heat exchange device 20 .

[0044] In this embodiment, the heat exchange device 20 is also provided with a remote liquid level gauge, which is arranged on the outer wall of the heat exchange device 20. The remote liquid level gauge includes a sensor module, a transmitter and a wireless transmission module. The sensor module is responsible for directly detecting the change of the liquid level and sending the liquid level information to the transmitter. The transmitter converts the liquid level information into an electrical signal and sends it to the control center of the air division through the wireless transmission module. The liquid level information of the heat exchange device 20 can be checked remotely to control the valve device of the low-temperature gas cooling recovery system, thereby realizing remote adjustment of the volume of the cold liquid medium.

[0045] In one embodiment, if Figure 1 As shown, an overflow pipe 207 is provided on the top of the heat exchange device 20 , and one end of the overflow pipe 207 is connected to the interior of the heat exchange device 20 .

[0046] In this embodiment, an overflow pipe 207 is provided on the top of the heat exchange device 20. When the liquid level of the liquid medium 202 to be cooled is too high, the excess liquid medium 202 to be cooled can be discharged to a safe area through the overflow pipe 207 on the top, thereby controlling the temperature of the cold liquid medium.

[0047] In one embodiment, if Figure 1As shown, the heat exchange device 20 is further provided with a circulation pipe 208 , both ends of which are connected to the heat exchange device 20 ; the circulation pipe 208 is provided with a circulation water pump 209 .

[0048] In this embodiment, the heat exchange device 20 is also provided with a circulation pipe 208, and both ends of the circulation pipe 208 are connected to the heat exchange device 20. Because the heat exchange device 20 has a certain flow space for the liquid medium 202 to be cooled to flow, the fluidity of the warm liquid medium can be further improved through the circulation water pump 209, thereby increasing the liquid of the cooling liquid medium contacting the low-temperature gas medium 101, improving the heat exchange efficiency, and reducing the temperature difference of the cold liquid medium.

[0049] In one embodiment, if Figure 1 As shown, the heat exchange device 20 is further provided with a liquid medium replenishing pipeline 210 for cooling, and the liquid outlet of the liquid medium replenishing pipeline 210 for cooling is arranged close to the medium inlet.

[0050] In this embodiment, the heat exchange device 20 is also provided with a liquid medium to be cooled replenishing pipeline 210. Because the low-temperature liquid in the cold liquid storage tank 10 is continuously vaporized into the low-temperature gas medium 101, and the second pipeline 301 will continuously transport the cold liquid medium to the water cooling tower 30, it is necessary to replenish the liquid medium to be cooled 202 to the heat exchange device 20 so that the cold energy of the low-temperature gas medium 101 can be continuously recovered; further, the liquid outlet of the liquid medium to be cooled replenishing pipeline 210 is arranged close to the medium inlet. Such an arrangement can make the liquid medium to be cooled 202 flowing into the heat exchange device 20 contact the low-temperature gas medium 101 as soon as possible, thereby improving the heat exchange efficiency of the low-temperature gas cold energy recovery system.

[0051] In one embodiment, if Figure 1 As shown, the cold liquid storage tank 10 also includes an exhaust pipe 102, one end of which is connected to the interior of the cold liquid storage tank 10; the exhaust pipe 102 is provided with a pressure regulating valve 103, and the pressure regulating valve 103 can adjust the internal air pressure of the cold liquid storage tank 10; one end of the first pipe 201 is connected to the exhaust pipe 102.

[0052] In the present embodiment, the cold liquid storage tank 10 also includes an emptying pipe 102, one end of the emptying pipe 102 is connected to the interior of the cold liquid storage tank 10, and the emptying pipe 102 is provided with a pressure regulating valve 103. When the air pressure in the cold liquid storage tank 10 approaches or exceeds the threshold of the safety air pressure, the discharge of the low-temperature gas medium 101 is accelerated by adjusting the number of opening circles of the pressure regulating valve 103. At the same time, one end of the first pipe 201 can be connected to the emptying pipe 102. When the low-temperature gas medium 101 enters the emptying pipe 102, it can be directly emptied or enter the first pipe 201 to be transferred to the heat exchange device 20; further, the low-temperature gas cold recovery system is provided with a pipeline branch in the first pipe 201, and the two ends of the pipeline branch are respectively connected to the first pipe 201 and the emptying pipe 102, and the pipeline branch is provided with a control valve. When the heat exchange device 20 does not need to perform heat exchange, the control valve is fully opened and closed, and the low-temperature gas medium 101 is only emptied through the emptying pipe 102.

[0053] The above are only preferred embodiments of the present invention, and do not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the utility model concept, or directly / indirectly used in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A low-temperature gas cooling recovery system, characterized in that: The low-temperature gas cooling capacity recovery system comprises: A cold liquid storage tank (10), wherein a low-temperature gas medium (101) is provided inside the cold liquid storage tank (10); A heat exchange device (20), the heat exchange device (20) comprising a medium inlet and a medium outlet connected to the medium inlet, the medium inlet being connected to the cold liquid storage tank (10) via a first pipe (201), a liquid medium (202) to be cooled is provided inside the heat exchange device (20), and the liquid medium (202) to be cooled can be heat exchanged with the low-temperature gas medium (101) to form a cold liquid medium; and A water cooling tower (30), wherein the water cooling tower (30) is connected to the medium outlet via a second pipe (301), and the cold liquid medium is transferred to the water cooling tower (30) via the second pipe (301).

2. The low-temperature gas refrigeration recovery system according to claim 1, characterized in that: The first pipeline (201) is provided with a first regulating valve (203), and the second pipeline (301) is provided with a second pressure pump (302).

3. The low-temperature gas refrigeration recovery system according to claim 2, characterized in that: The outer wall of the heat exchange device (20) is provided with a remote thermometer (204), and the first pipeline (201) is also provided with a temperature control valve (205), and the temperature control valve (205) can receive an electrical signal from the remote thermometer (204).

4. The low-temperature gas refrigeration recovery system according to claim 3, characterized in that: The outer peripheral wall of the heat exchange device (20) is also provided with a plurality of on-site thermometers, and the plurality of on-site thermometers are arranged at intervals along the height direction of the heat exchange device (20).

5. The low-temperature gas refrigeration recovery system according to claim 1, characterized in that: The heat exchange device (20) is also provided with an on-site liquid level meter (206), and the on-site liquid level meter (206) is arranged on the outer peripheral wall of the heat exchange device (20).

6. The low-temperature gas refrigeration recovery system according to claim 5, characterized in that: The heat exchange device (20) is also provided with a remote liquid level gauge, and the remote liquid level gauge is arranged on the outer peripheral wall of the heat exchange device (20).

7. The low-temperature gas cooling energy recovery system according to any one of claims 1 to 6, characterized in that: An overflow pipe (207) is provided on the top of the heat exchange device (20), and one end of the overflow pipe (207) is connected to the interior of the heat exchange device (20).

8. The low-temperature gas refrigeration recovery system according to claim 7, characterized in that: The heat exchange device (20) is also provided with a circulation pipeline (208), and both ends of the circulation pipeline (208) are connected to the heat exchange device (20); the circulation pipeline (208) is provided with a circulation water pump (209).

9. The low-temperature gas refrigeration recovery system according to claim 8, characterized in that: The heat exchange device (20) is further provided with a liquid medium replenishing pipeline (210) for cooling down the liquid medium, and the liquid outlet of the liquid medium replenishing pipeline (210) for cooling down the liquid medium is arranged close to the medium inlet.

10. The low-temperature gas refrigeration recovery system according to claim 7, characterized in that: The cold liquid storage tank (10) further comprises an exhaust pipe (102), one end of which is connected to the interior of the cold liquid storage tank (10); the exhaust pipe (102) is provided with a pressure regulating valve (103), and the pressure regulating valve (103) is capable of regulating the internal air pressure of the cold liquid storage tank (10); one end of the first pipe (201) is connected to the exhaust pipe (102).

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