Leak-proof structure and CO2 heat pump heat supply system

Abstract

The utility model relates to the technical field of heat pumps, in particular to a leakproof structure and a CO2 heat pump heat supply system. The problem that an existing heat exchanger has the leakage risk is solved. In order to achieve the purpose, the anti-leakage structure and the CO2 heat pump heat supply system are provided, the anti-leakage structure comprises a heat exchanger, a liquid return pipeline, a liquid outlet pipeline, a pressure detection component, a control valve and a control part, one side of the heat exchanger communicates with the liquid return pipeline and the liquid outlet pipeline, the pressure detection component is arranged on the liquid outlet pipeline or the liquid return pipeline, and the control valve is arranged on the control part. The control valve is arranged on the liquid outlet pipeline; the control part is connected with the pressure detection component and the control valve, after the heat exchange wall is damaged, the pressure detected by the pressure detection component changes rapidly, and after the pressure reaches a certain value, the control valve can be made to block the liquid outlet pipeline through the control part, a large amount of fluid in the heat exchanger is prevented from rushing into a room, and then harm to the room is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of heat pumps, in particular to an anti-leakage structure and a CO2 heat pump heating system. Background Art

[0002] The CO2 heat pump system has the advantages of high heating temperature and strong low-temperature heating capacity, and has great application and promotion prospects in home / commercial scenarios such as heat pump water heaters and heat pump floor heating. Unlike traditional refrigerants, the operating pressure of CO2 as a refrigerant exceeds 10MPa, which poses a risk of excessive pressure, and has high requirements for the pressure resistance and safety of CO2 heat pump system components.

[0003] The heat exchanger is the key component for heat conversion and the location for energy transfer between indoor and outdoor areas. Water and CO2 are separated by only a wall. Once the heat exchange wall is damaged, high-pressure CO2 will rush into the water system pipe and then enter the user's room, causing harm to the room.

[0004] Accordingly, the art needs a new technical solution to solve the above problems. Utility Model Content

[0005] In order to solve at least one of the above problems in the prior art, that is, to solve the problem of leakage risk of the existing heat exchanger, the present application provides an anti-leakage structure, which includes:

[0006] A heat exchanger, wherein the heat exchanger has a refrigerant inlet, a refrigerant outlet, a liquid inlet, and a liquid outlet;

[0007] A liquid return pipeline, one end of which is connected to the liquid inlet;

[0008] A liquid outlet pipeline, one end of which is connected to the liquid outlet;

[0009] A pressure detection component, wherein the pressure detection component is arranged on the liquid outlet pipeline or the liquid return pipeline;

[0010] A control valve, the control valve being arranged on the liquid outlet pipeline;

[0011] A control unit is connected to the pressure detection component and the control valve respectively, and is configured to control the on-off of the control valve based on the detection result of the pressure detection component.

[0012] When the above technical solution is adopted, after the heat exchange wall is damaged, the pressure detected by the pressure detection component changes rapidly. After the pressure reaches a certain value, the control valve can be used by the control unit to block the liquid outlet pipeline to prevent a large amount of fluid in the heat exchanger from rushing into the room, thereby avoiding harm to the room.

[0013] In the preferred technical solution of the above anti-leakage structure, the pressure detection component is configured as a pressure sensor, and / or

[0014] The pressure detection component is arranged on the liquid outlet pipeline and is close to the liquid outlet of the heat exchanger.

[0015] When the above technical solution is adopted, the pressure sensor can quickly detect the pressure change at the heat exchanger, providing a prerequisite for the rapid response of the control valve.

[0016] In the preferred technical solution of the above-mentioned anti-leakage structure, the control unit is configured as a pressure relay.

[0017] When the above technical solution is adopted, the pressure relay can automatically cause the control valve to block the liquid outlet pipeline according to the pressure.

[0018] In a preferred technical solution of the above-mentioned anti-leakage structure, the anti-leakage structure further includes a first pressure relief valve, which is arranged in the liquid return pipeline and located upstream of the liquid inlet.

[0019] When the above technical solution is adopted, a certain pressure in the liquid outlet pipeline and the liquid return pipeline near the heat exchanger can be released through the first pressure relief valve, thereby preventing secondary damage caused by excessive pressure in the pipeline.

[0020] In a preferred technical solution of the above-mentioned anti-leakage structure, the anti-leakage structure further includes a safety valve, which is arranged in the liquid return pipeline and located upstream of the first pressure relief valve.

[0021] When the above technical solution is adopted, the safety valve can further prevent the fluid in the heat exchanger from flowing back into the room through the return liquid pipeline.

[0022] In the preferred technical solution of the above anti-leakage structure, the safety valve is a one-way valve, or

[0023] The safety valve is a self-closing valve, or,

[0024] The safety valve is connected to the control unit, and the safety valve is a solenoid valve.

[0025] When the safety valve is set as a one-way valve, the one-way valve can prevent the liquid in the return liquid pipeline from flowing back. When the safety valve is set as a self-closing valve, the self-closing valve can block the return liquid pipeline when a certain flow rate or pressure is reached. When the safety valve is set as a solenoid valve, the solenoid valve can also block the return liquid pipeline under the action of the control unit.

[0026] In a preferred technical solution of the anti-leakage structure, the anti-leakage structure further includes a second pressure relief valve, which is arranged in the liquid outlet pipeline and located downstream of the control valve.

[0027] When the above technical solution is adopted, since part of the fluid in the heat exchanger has already rushed into the liquid outlet pipeline downstream of the control valve before the control valve blocks the liquid outlet pipeline, the second pressure relief valve can release the pressure accumulated in the liquid outlet pipeline downstream of the control valve, thereby protecting the overall stability and safety of the pipeline.

[0028] In a preferred technical solution of the above-mentioned anti-leakage structure, the pressure relief pressure of the first pressure relief valve is greater than the pressure relief pressure of the second pressure relief valve.

[0029] When the above technical solution is adopted, the overall stability and safety of the pipeline can be further guaranteed.

[0030] The present application also provides a CO2 heat pump heating system, which includes the anti-leakage structure described in any one of the above items.

[0031] In the preferred technical solution of the above-mentioned CO2 heat pump heating system, the CO2 heat pump heating system is a heat pump water heater or a heat pump heating system.

[0032] When the above-mentioned anti-leakage structure is adopted, the CO2 heat pump heating system can prevent a large amount of fluid in the heat exchanger from rushing into the room, thereby avoiding harm to the room. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The anti-leakage structure of the present application is described below with reference to the accompanying drawings and in combination with a CO2 heat pump heating system. In the accompanying drawings:

[0034] Figure 1 A schematic diagram of the anti-leakage structure of the present application;

[0035] Reference numerals list

[0036] 10. Heat exchanger; 11. Refrigerant inlet; 12. Refrigerant outlet; 13; Liquid inlet; 14. Liquid outlet; 15. Heat exchange wall; 21. Liquid return pipeline; 22. Liquid outlet pipeline; 23. Water pump; 30. Pressure detection component; 40. Control valve; 50. Control unit; 60. First pressure relief valve; 70. Safety valve; 80. Expansion water tank; 90. Second pressure relief valve. DETAILED DESCRIPTION

[0037] The preferred embodiments of the present application are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present application and are not intended to limit the scope of protection of the present application. For example, although the anti-leakage structure in the present embodiment is introduced in conjunction with a CO2 heat pump heating system, this is not intended to limit the scope of protection of the present application. Without departing from the principles of the present application, those skilled in the art may apply the present application to other application scenarios. For example, the anti-leakage structure in the present embodiment is applied to other heat pump systems.

[0038] It should be noted that in the description of the present application, the terms "upper", "lower", "inner", "outer" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings, which are only for the convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0039] In addition, it should be noted that in the description of this application, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0040] As described in the background technology, the CO2 heat pump system has the advantages of high heating temperature and strong low-temperature heating capacity, and has great application prospects in heat pump water heaters, heat pump floor heating, and other home / commercial scenarios. Unlike traditional refrigerants, the operating pressure of CO2 as a refrigerant exceeds 10MPa, and there is a risk of excessive pressure, which places high requirements on the pressure resistance and safety of CO2 heat pump system components.

[0041] The heat exchanger is the key component for heat conversion and the location for energy transfer between indoor and outdoor areas. Water and CO2 are separated by only a wall. Once the heat exchange wall is damaged, high-pressure CO2 will rush into the water system pipe and then enter the user's room, causing harm to the room.

[0042] In order to solve the problem of leakage risk in existing heat exchangers, the present application provides an anti-leakage structure, which includes: a heat exchanger, the heat exchanger has a refrigerant inlet, a refrigerant outlet, a liquid inlet and a liquid outlet; a liquid return pipeline, one end of which is connected to the liquid inlet; a liquid outlet pipeline, one end of which is connected to the liquid outlet; a pressure detection component, the pressure detection component is arranged on the liquid outlet pipeline or the liquid return pipeline; a control valve, the control valve is arranged on the liquid outlet pipeline; a control unit, the control unit is respectively connected to the pressure detection component and the control valve, and the control unit is configured to control the on and off of the control valve based on the detection result of the pressure detection component.

[0043] When the above technical solution is adopted, after the heat exchange wall is damaged, the pressure detected by the pressure detection component changes rapidly. After the pressure reaches a certain value, the control valve can be used by the control unit to block the liquid outlet pipeline to prevent a large amount of fluid in the heat exchanger from rushing into the room, thereby avoiding harm to the room.

[0044] Refer to the following Figure 1 The anti-leakage structure of the present application is described in combination with the CO2 heat pump heating system. Figure 1 This is a schematic diagram of the anti-leakage structure of the present application.

[0045] like Figure 1 As shown, in a preferred embodiment, the CO2 heat pump heating system is provided with an anti-leakage structure, which includes a heat exchanger 10, the heat exchanger 10 has a refrigerant inlet 11, a refrigerant outlet 12, a liquid inlet 13, a liquid outlet 14 and a heat exchange wall 15, the liquid inlet 13 is connected to the return liquid pipeline 21, and the liquid outlet 14 is connected to the liquid outlet pipeline 22, the anti-leakage structure also includes a pressure detection component 30, a control valve 40 and a control unit 50, the pressure detection component 30 and the control valve 40 are both arranged on the liquid outlet pipeline 22, and the pressure detection component 30 is close to the liquid outlet 14, the control valve 40 is located downstream of the pressure detection component 30, and the control unit 50 is respectively connected to the pressure detection component 30 and the control valve 40.

[0046] In this embodiment, the heat exchanger 10 is configured as a plate heat exchanger, the pressure detection component 30 is configured as a pressure sensor, the control valve 40 is configured as a solenoid valve, and the control unit 50 is configured as a pressure relay. During the operation of the CO2 heat pump heating system, the fluids on both sides of the heat exchanger 10 complete heat exchange, and after the heat exchange wall 15 is damaged, the high-pressure CO2 on one side may rush into the return liquid pipeline 21 and the liquid outlet pipeline 22. At this time, the pressure detection component 30 (pressure sensor) can detect the surge in pressure on the liquid outlet pipeline 22 at the liquid outlet 14, and transmit a signal to the control unit 50 (pressure relay). At this time, the pressure relay stops supplying power to the control valve 40 (solenoid valve), so that the control valve 40 (solenoid valve) blocks the liquid outlet pipeline 22, thereby preventing the high-pressure CO2 from entering the user's room from the liquid outlet pipeline 22.

[0047] It is understood by those skilled in the art that, although the anti-leakage structure in this embodiment is described in combination with the CO2 heat pump heating system and the plate heat exchanger, this is not intended to limit the scope of protection of the present application. The anti-leakage structure in the present application can also be applied to other heat pump systems. Those skilled in the art can also replace the type of heat exchanger 10 according to needs, for example, the heat exchanger 10 can be set as a shell and tube heat exchanger, a shell and tube heat exchanger, etc. In addition, the coordination of the pressure sensor, the pressure relay and the solenoid valve is not static. In an alternative embodiment, the pressure detection component 30 can be set as a pressure gauge, and the control unit 50 can be set as a single-chip microcomputer, a PLC controller, etc. The controller is connected to the pressure gauge and can read the pressure value. After reaching a certain pressure value, the controller can send a signal to the control valve 40, and the control valve 40 can block the liquid outlet pipeline 22 according to the signal received from the controller. After the high-pressure CO2 enters the water side pipeline, that is, the return liquid pipeline 21 and the liquid outlet pipeline 22, the pressure detected by the pressure detection component 30 changes rapidly. At this time, the controller transmits a closing signal to the control valve 40, thereby blocking the liquid outlet pipeline 22. In addition, the location where the pressure detection component 30 is set can also be changed according to the needs of those skilled in the art, as long as the pressure change at the heat exchanger 10 can be monitored. In an alternative embodiment, the pressure detection component 30 is set on the liquid return line 21 and is located upstream of the liquid inlet 13. In another alternative embodiment, the pressure detection component 30 is set inside the heat exchanger 10.

[0048] Furthermore, the anti-leakage structure also includes a first pressure relief valve 60 and a safety valve 70 , wherein the first pressure relief valve 60 is arranged in the return liquid pipeline 22 and located upstream of the liquid inlet 13 , and the safety valve 70 is also arranged in the return liquid pipeline 22 and located upstream of the first pressure relief valve 60 .

[0049] In this embodiment, the safety valve 70 is set as a one-way valve. At this time, the one-way valve can ensure that the high-pressure CO2 will not flow back from the return liquid pipeline 21. Under the action of the control valve 40 and the safety valve 70, the pressure in the intermediate pipeline begins to increase, and the first pressure relief valve 60 can start to release the pressure after the pressure reaches a certain level. Among them, the setting of the safety valve 70 (one-way valve) not only prevents the high-pressure CO2 from entering the room and causing harm to the user, but also prevents the backflow in the return liquid pipeline 21 from damaging the components upstream of the safety valve 70. At the same time, the first pressure relief valve 60 can also prevent secondary damage caused by excessive pressure in the pipeline, thereby improving the overall stability and safety of the pipeline.

[0050] It is understood by those skilled in the art that the specific setting of the first pressure relief valve 60 is not fixed. In an alternative embodiment, the first pressure relief valve 60 can be set on the liquid outlet pipeline 22 downstream of the pressure detection component 30. Of course, the first pressure relief valve 60 may not be set, but considering the overall stability and safety of the pipeline, setting the first pressure relief valve 60 is a better choice. In addition, the setting of the safety valve 70 is not static, and those skilled in the art can change it according to needs. In an alternative embodiment, the safety valve 70 is set to the same solenoid valve as the control unit 40, and both solenoid valves are connected to the pressure relay. Of course, the safety valve 70 can also be omitted. After the heat exchange wall 15 is damaged, the water pump 23 located upstream of the safety valve 70 maintains normal operation, which can prevent CO2 from entering the return liquid pipeline 21 and backflowing to a certain extent.

[0051] Furthermore, the anti-leakage structure also includes an expansion water tank 80 and a second pressure relief valve 90, wherein the expansion water tank 80 is arranged in the liquid outlet pipeline 22 and is located downstream of the control valve 60, the second pressure relief valve 90 is arranged in the liquid outlet pipeline 22 and is located downstream of the expansion water tank 80, and the pressure relief pressure of the first pressure relief valve 60 is greater than the pressure relief pressure of the second pressure relief valve 90.

[0052] In this embodiment, the expansion water tank 80 can absorb and compensate for the pressure change caused by thermal expansion and contraction of the liquid outlet pipeline 22 by adding a certain amount of water in the system, thereby ensuring the overall stable operation of the CO2 heat pump heating system, and the second pressure relief valve 90 can discharge excess water inside the liquid outlet pipeline 22 and the expansion water tank 80 to prevent excessive water accumulation from causing excessive pressure inside the CO2 heat pump heating system as a whole, thereby ensuring the normal operation and safety of the heating system. After the heat exchange wall 15 is damaged, high-pressure CO2 enters the water system, that is, the return liquid pipeline 21 and the liquid outlet pipeline 22, and the control valve 40 blocks the liquid outlet pipeline 22. At this time, the pressure in the pipeline between the safety valve 70 and the control valve 40 increases rapidly, and the first pressure relief valve 60 opens to release pressure. In addition, before the control valve 40 blocks the liquid outlet pipeline 22, part of the CO2 has entered the liquid outlet pipeline 22 downstream of the control valve 40. The expansion water tank 80 and the second pressure relief valve 90 can ensure that the pressure in the liquid outlet pipeline 22 is reduced when the control valve 40 is not closed in time, further ensuring the normal operation and safety of the heating system. Preferably, the pressure relief pressure of the first pressure relief valve 60 is set to 1MPa, and the pressure relief pressure of the second pressure relief valve 90 is set to 0.8MPa.

[0053] It is understood by those skilled in the art that the set values ​​of the pressure relief pressures of the first pressure relief valve 60 and the second pressure relief valve 90 are not fixed and can be modified by those skilled in the art as needed. In addition, the provision of the expansion water tank 80 and the second pressure relief valve 90 is not necessary. When the return liquid pipeline 21 and the liquid outlet pipeline 22 themselves have sufficient working strength, they can withstand a certain pressure. However, considering the normal operation and safety of the heating system as a whole, provision of the expansion water tank 80 and the second pressure relief valve 90 is a better choice.

[0054] It should also be explained that the CO2 heat pump heating system in this embodiment is a heat pump water heater or a heat pump heating system. When the above anti-leakage structure is adopted, when the heat exchanger is damaged, high-pressure CO2 can be prevented from rushing into the room from the liquid pipeline in large quantities, thereby avoiding damage to the room.

[0055] Those skilled in the art will appreciate that, although some embodiments described herein include certain features included in other embodiments but not other features, the combination of features of different embodiments is meant to be within the scope of the present application and form different embodiments. For example, in the claims of the present application, any one of the claimed embodiments may be used in any combination.

[0056] So far, the technical solutions of the present application have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present application is obviously not limited to these specific embodiments. Without departing from the principles of the present application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present application.

Claims

1. A leakage prevention structure, characterized in that: include: A heat exchanger, wherein the heat exchanger has a refrigerant inlet, a refrigerant outlet, a liquid inlet, and a liquid outlet; A liquid return pipeline, one end of which is connected to the liquid inlet; A liquid outlet pipeline, one end of which is connected to the liquid outlet; A pressure detection component, wherein the pressure detection component is arranged on the liquid outlet pipeline or the liquid return pipeline; A control valve, the control valve being arranged on the liquid outlet pipeline; A control unit is connected to the pressure detection component and the control valve respectively, and is configured to control the on-off of the control valve based on the detection result of the pressure detection component.

2. The anti-leakage structure according to claim 1, characterized in that: The pressure detection component is configured as a pressure sensor, and / or The pressure detection component is arranged on the liquid outlet pipeline and is close to the liquid outlet of the heat exchanger.

3. The anti-leakage structure according to claim 1, characterized in that: The control unit is configured as a pressure relay.

4. The anti-leakage structure according to claim 1, characterized in that: The anti-leakage structure further includes a first pressure relief valve, which is arranged in the liquid return pipeline and located upstream of the liquid inlet.

5. The anti-leakage structure according to claim 4, characterized in that: The anti-leakage structure further includes a safety valve, which is arranged in the liquid return pipeline and located upstream of the first pressure relief valve.

6. The anti-leakage structure according to claim 5, characterized in that: The safety valve is a one-way valve, or The safety valve is connected to the control unit, and the safety valve is a solenoid valve.

7. The anti-leakage structure according to claim 6, characterized in that: The anti-leakage structure further includes a second pressure relief valve, which is arranged in the liquid outlet pipeline and located downstream of the control valve.

8. The anti-leakage structure according to claim 7, characterized in that: The relief pressure of the first pressure relief valve is greater than the relief pressure of the second pressure relief valve.

9. A CO2 heat pump heating system, characterized in that: The CO2 heat pump heating system comprises the anti-leakage structure according to any one of claims 1-8.

10. The CO2 heat pump heating system according to claim 9, characterized in that: The CO2 heat pump heating system is a heat pump water heater or a heat pump heating system.

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