Self-cooling refrigerant recovery system

Abstract

The present application relates to the field of refrigeration, in particular to a self-cooling refrigerant recovery system, comprising: a compressor, an inlet of which is communicated with an outlet of a first container; a reversing part, comprising a reversing inlet, a first reversing outlet and a second reversing outlet; the reversing inlet is communicated with an outlet of the compressor; the reversing part can make the reversing inlet communicated with the first reversing outlet, or make the reversing inlet communicated with the second reversing outlet; a second container, an inlet of which is communicated with the second reversing outlet; a first heat exchanger, an inlet of which is communicated with the outlet of the compressor, and an outlet of the first heat exchanger is communicated with the inlet of the reversing part; a throttling device, an inlet of which is communicated with the first reversing outlet, and an outlet of the throttling device is communicated with the inlet of the compressor; a second heat exchanger, an inlet of which is communicated with the outlet of the throttling device and can cool the second container to solve the technical problem that the refrigerant in the recovery container needs to be cooled and an additional refrigeration system needs to be increased.

Description

Technical Field

[0001] This invention relates to the field of refrigeration, and more specifically to a self-cooling refrigerant recovery system. Background Technology

[0002] Refrigerant is the "blood" of refrigeration systems, widely used in household air conditioners, refrigerators, chillers, and other refrigeration equipment. However, refrigerant is also a non-CO2 greenhouse gas; direct emission into the atmosphere will cause environmental pollution and resource waste. As the world's largest producer and consumer of refrigeration equipment and refrigerants, refrigerant recycling is an effective measure for my country to reduce greenhouse gas emissions.

[0003] Compression condensation is one of the commonly used methods for refrigerant recovery. The refrigerant is compressed and condensed into a high-temperature, high-pressure liquid state before entering a recovery container. This container is typically kept at room temperature, but the pressure and temperature increase as recovery progresses. Lowering the temperature inside the recovery container effectively improves the refrigerant recovery speed and rate. Current technologies use an external refrigeration system to cool the container. This requires an additional refrigeration system, which complicates the refrigerant recovery process, makes maintenance difficult, and increases equipment maintenance costs. Furthermore, the additional refrigeration system consumes extra refrigerant, hindering resource conservation.

[0004] There is currently no good solution to the above-mentioned technical problems. Summary of the Invention

[0005] To address the technical challenge of requiring an additional refrigeration system to cool the refrigerant inside the recovery container, a self-cooling refrigerant recovery system is proposed.

[0006] The self-cooling refrigerant recovery system is used to recover the refrigerant in the first container, including:

[0007] The compressor has its inlet connected to the outlet of the first container;

[0008] A reversing section includes a reversing inlet, a first reversing outlet, and a second reversing outlet; the reversing inlet is connected to the outlet of the compressor; the reversing section enables the reversing inlet to connect with the first reversing outlet, or to connect the reversing inlet with the second reversing outlet.

[0009] The second container has its inlet connected to the second reversing outlet;

[0010] The inlet of the first heat exchanger is connected to the outlet of the compressor, and the outlet of the first heat exchanger is connected to the inlet of the switching section.

[0011] A throttling device, the inlet of which is connected to the first reversing outlet, and the outlet of the throttling device being connected to the inlet of the compressor;

[0012] The second heat exchanger has its inlet connected to the outlet of the throttling device and is capable of cooling the second container.

[0013] Preferably, the self-cooling refrigerant recovery system further includes a first oil separator, the inlet of which is connected to the outlet of the first container, and the outlet of which is connected to the inlet of the compressor.

[0014] Preferably, the outlet of the second heat exchanger is connected to the inlet of the first oil separator.

[0015] Preferably, the self-cooling refrigerant recovery system further includes a third heat exchanger, the inlet of which is connected to the outlet of the compressor, and the outlet of which is connected to the inlet of the first heat exchanger; the third heat exchanger is thermally coupled to the first oil separator.

[0016] Preferably, the self-cooling refrigerant recovery system further includes a first filter device, the inlet of which is connected to the outlet of the first container, and the outlet of which is connected to the outlet of the second heat exchanger.

[0017] Preferably, the self-cooling refrigerant recovery system further includes a second filter device, the inlet of which is connected to the outlet of the first heat exchanger, and the outlet of which is connected to the inlet of the reversing section.

[0018] Preferably, the self-cooling refrigerant recovery system further includes a second oil separator, the inlet of which is connected to the outlet of the compressor, the outlet of which is connected to the inlet of the third heat exchanger, and the oil outlet of which is connected to the oil return port of the compressor.

[0019] Preferably, the reversing part is a three-way pipe, which includes an inlet pipe, a circulation outlet pipe, and a storage outlet pipe;

[0020] The inlet pipe is connected to the outlet of the first heat exchanger, the circulation outlet pipe is connected to the inlet of the throttling device, and the storage outlet pipe is connected to the inlet of the second container;

[0021] A first control valve is provided on the circulation outlet pipe, and a second control valve is provided on the storage outlet pipe.

[0022] Preferably, a third control valve is provided at the outlet end of the second heat exchanger.

[0023] Preferably, the first control valve, the second control valve, and the third control valve are all solenoid valves;

[0024] The self-cooling refrigerant recovery system includes a cooling mode and a recovery mode;

[0025] The recycling mode is as follows: the first control valve is closed, and the second and third control valves are open;

[0026] The cooling mode is as follows: the second control valve is closed, and the first control valve and the third control valve are open.

[0027] This invention achieves the cooling of the recovered high-temperature and high-pressure refrigerant by changing the flow path of the refrigerant to be recovered in the refrigerant recovery system. This solves the technical problem of needing to add an additional refrigeration system to cool the refrigerant in the recovery container, thereby improving maintainability and reducing costs. Since no additional refrigeration system is required, the consumption of refrigerant is reduced accordingly, ultimately improving the refrigerant recovery speed and recovery rate. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of a self-cooling refrigerant recovery system according to an embodiment of the present invention;

[0029] The reference numerals in the attached figures are as follows:

[0030] 1. First container; 2. Second container; 3. Compressor; 301. Sight glass; 4. Reversing unit; 401. Inlet pipe; 402. Circulation outlet pipe; 403. Storage outlet pipe; 501. First heat exchanger; 502. Second heat exchanger; 503. Third heat exchanger; 6. Throttling device; 701. First oil separator; 702. Second oil separator; 801. First filter; 802. Second filter; 901. First control valve; 902. Second control valve; 903. Third control valve. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] The terminology used in the embodiments of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms “a,” “the,” and “the” used in the embodiments of this invention and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise. “Multiple” generally includes at least two, but does not exclude the inclusion of at least one.

[0033] It should be understood that the term "and / or" used in this document is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Furthermore, the character " / " in this document generally indicates that the related objects are in an "or" relationship; "first" and "second" are used only to distinguish different technical features, not to indicate a chronological order; and "upper," "lower," "before," and "after" are used only to more conveniently illustrate the positional relationship of technical features and only have meaning when combined with actual usage or the specific location descriptions in the preceding text, and are not absolute positional relationships.

[0034] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a product or system comprising a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a product or system. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the product or system that includes said element.

[0035] This invention relates to the field of refrigeration, and more specifically to a self-cooling refrigerant recovery system.

[0036] Refrigerant is the "blood" of refrigeration systems, widely used in household air conditioners, refrigerators, chillers, and other refrigeration equipment. However, refrigerant is also a non-CO2 greenhouse gas; direct emission into the atmosphere will cause environmental pollution and resource waste. As the world's largest producer and consumer of refrigeration equipment and refrigerants, facing the pressure of "carbon peaking" and "carbon neutrality," as well as the requirements of the Kigali Amendment to the Montreal Protocol, refrigerant recycling is an effective measure for my country to reduce greenhouse gas emissions. Compression condensation is one of the commonly used methods for refrigerant recycling. The refrigerant is compressed and condensed into a high-temperature, high-pressure liquid before entering a recycling container. The recycling container is generally at room temperature, and the pressure and temperature inside the container increase as recycling progresses. Lowering the temperature inside the recycling container will effectively improve the refrigerant recycling speed and rate. Current technology uses an external refrigeration system to cool the recycling container. This solution requires an additional refrigeration system, which makes the refrigerant recycling system more complex, difficult to maintain, and has higher social security maintenance costs. Moreover, the additional refrigeration system consumes additional refrigerant, which is not conducive to resource conservation.

[0037] To address the aforementioned technical problems, a self-cooling refrigerant recovery system is proposed for recovering refrigerant from a first container 1. The system includes: a compressor 3, whose inlet is connected to the outlet of the first container 1; a reversing section 4, including a reversing inlet, a first reversing outlet, and a second reversing outlet; the reversing inlet is connected to the outlet of the compressor 3; the reversing section 4 can connect the reversing inlet to the first reversing outlet, or connect the reversing inlet to the second reversing outlet; a second container 2, whose inlet is connected to the second reversing outlet; a first heat exchanger 501, whose inlet is connected to the outlet of the compressor 3, and whose outlet is connected to the inlet of the reversing section 4; a throttling device 6, whose inlet is connected to the first reversing outlet, and whose outlet is connected to the inlet of the compressor 3; and a second heat exchanger 502, whose inlet is connected to the outlet of the throttling device 6 and is capable of cooling the second container 2.

[0038] First, it should be noted that in the claims and specification, "connected" includes both "connected" and "closed" states; "connected" includes both "direct" connection through other components and "indirect" connection through other components. The working process of the self-cooling refrigerant recovery system is as follows: First, vacuuming is performed on all components except the first container 1 (vacuuming is a conventional method, and the specific technical features required are not described here); Second, the connection between the first reversing outlet and the inlet of the second heat exchanger 502 is closed, while the connection between the second reversing outlet and the inlet of the second container 2 is established; Third, the compressor 3 is started, and the refrigerant in the first container 1 is compressed into a high-temperature liquid state by the compressor 3, then cooled by heat exchange in the first heat exchanger 501 and flows into the second container 2 for storage; in this step, the compressor 3 drives the refrigerant flow and compresses the refrigerant; Fourth, when the temperature sensor detects that the temperature of the second container 2 is higher than a first preset value, the connection between the first reversing outlet and the second heat exchanger 502 is established. The inlet of the first container 1 is connected to the outlet of the second container 2, while the outlet of the second reversing device is disconnected from the inlet of the second container 2. At this point, the refrigerant temperature decreases further after passing through the throttling device 6. The low-temperature refrigerant cools the second container 2 as it flows through the second heat exchanger 502. After being cooled, the refrigerant re-enters the compressor 3, is compressed, and then flows out, thus circulating to cool the second container 2. In the fifth step, when the temperature of the second container 2 detected by the temperature sensor is lower than the second preset temperature (which is lower than the first preset temperature), the outlet of the first reversing device is disconnected from the inlet of the second heat exchanger 502, and the outlet of the second reversing device is connected to the inlet of the second container 2. Then, steps four and five are repeated until all the refrigerant in the first container 1 flows into the second container 2. A fan can be installed on one side of the first heat exchanger 501 to accelerate heat exchange between the first heat exchanger 501 and the outside air.

[0039] Compared to existing methods that rely on additional refrigerant flow to cool the recovered refrigerant (the container holding the refrigerant), the self-cooling refrigerant recovery system achieves cooling of the already recovered high-temperature, high-pressure refrigerant by altering the flow path of the refrigerant to be recovered within the system. This solves the technical problem of requiring an additional refrigeration system to cool the refrigerant in the recovery container, and reduces refrigerant consumption. Since no additional refrigeration system is needed, refrigerant consumption is correspondingly reduced, ultimately improving the refrigerant recovery speed and rate. Compressor 3 can be an oil-free compressor.

[0040] Preferably, the self-cooling refrigerant recovery system further includes a first oil separator 701, the inlet of which is connected to the outlet of the first container 1, and the outlet of which is connected to the inlet of the compressor 3.

[0041] Before entering the compressor 3, the refrigerant to be recovered first passes through the first oil separator 701 to separate the oil contaminants in the refrigerant, which helps to improve the purity of the refrigerant entering the compressor 3 and improves the compression efficiency of the refrigerant. The first oil separator 701 can be a distillation vessel. The distillation vessel can not only separate the lubricating oil in the refrigerant, but also separate the water and acidic liquids in the refrigerant, further improving the purity of the refrigerant. A filter screen can be set in the distillation vessel to further filter the solid impurity particles in the refrigerant. Whether cooling the second container 2 or storing the refrigerant in the second container 2, the refrigerant will pass through the first oil separator 701 after flowing out of the first container 1, which improves the purification efficiency of the refrigerant.

[0042] A sight glass 301 can be installed at the inlet end of the first oil separator 701 to observe the flow state of the refrigerant.

[0043] Preferably, the outlet of the second heat exchanger 502 is connected to the inlet of the first oil separator 701.

[0044] By connecting the outlet of the second heat exchanger 502 to the inlet of the first oil separator 701, the refrigerant can pass through the first oil separator 701 multiple times during the circulating cooling process, thereby further improving the purity of the refrigerant.

[0045] Preferably, the self-cooling refrigerant recovery system further includes a third heat exchanger 503, the inlet of which is connected to the outlet of the compressor 3, and the outlet of which is connected to the inlet of the first heat exchanger 501; the third heat exchanger 503 is thermally coupled to the first oil separator 701.

[0046] Thermal coupling is a heat transfer connection that can be achieved through heat transfer, heat convection, or heat radiation, or any combination of these three methods. The high-temperature refrigerant flowing from the compressor 3 outlet heats the first oil separator 701 as it passes through the third heat exchanger 503, accelerating the purification efficiency of the refrigerant and initially lowering its temperature. After this initial cooling, the refrigerant passes through the first heat exchanger 501, further reducing its temperature and improving the cooling efficiency of the refrigerant on the second container 2.

[0047] Preferably, the self-cooling refrigerant recovery system further includes a first filter device 801, the inlet of which is connected to the outlet of the first container 1, and the outlet of the first filter device 801 is connected to the outlet of the second heat exchanger 502.

[0048] When the refrigerant flowing out of the first container 1 passes through the first filter device 801, water, acidic liquid and solid particles in the refrigerant are filtered out, which not only improves the purity of the refrigerant, but also reduces the workload of the first oil separator 701. Since the first oil separator 701 has higher impurity removal accuracy for the refrigerant, it also extends the service life of the first oil separator 701. The first filter device 801 can be a drying filter device.

[0049] Preferably, the self-cooling refrigerant recovery system further includes a second filter device 802, the inlet of which is connected to the outlet of the first heat exchanger 501, and the outlet of which is connected to the inlet of the reversing section 4.

[0050] Before flowing out of the reversing section 4, the refrigerant passes through the second filter device 802 again for filtration. This not only filters out water, acidic liquids, and solid particles in the refrigerant, but also prevents lubricating oil and solid particles contained in the refrigerant after passing through the compressor 3 from affecting the reversing section 4. This also prevents refrigerant leakage caused by improper closure of the first or second reversing outlet of the reversing section 4 when it needs to be shut off. The second filter device 802 can be a dryer filter.

[0051] Preferably, the self-cooling refrigerant recovery system further includes a second oil separator 702, the inlet of which is connected to the outlet of the compressor 3, the outlet of which is connected to the inlet of the third heat exchanger 503, and the oil outlet of which is connected to the oil return port of the compressor 3.

[0052] The third heat exchanger 503 can further purify the refrigerant. The refrigerant purified by the third oil separator can improve the heat exchange efficiency of the third heat exchanger 503 when it flows through the third heat exchanger 503, thereby improving the purification efficiency of the first oil separator 701.

[0053] Preferably, the reversing section 4 is a three-way pipe, which includes an inlet pipe 401, a circulation outlet pipe 402, and a storage outlet pipe 403; the inlet pipe 401 is connected to the outlet of the first heat exchanger 501, the circulation outlet pipe 402 is connected to the inlet of the throttling device 6, and the storage outlet pipe 403 is connected to the inlet of the second container 2; a first control valve 901 is provided on the circulation outlet pipe 402, and a second control valve 902 is provided on the storage outlet pipe 403.

[0054] A three-way pipe is installed, and a first control valve 901 is installed on the circulation outlet pipe 402, and a second control valve 902 is installed on the storage outlet pipe 403. The flow path of the refrigerant to be recovered is controlled by controlling the "stop" and "connect" states of the first control valve 901 and the second control valve 902. This control method is simple, convenient, easy to control, and easy to achieve automatic control.

[0055] Preferably, a third control valve 903 is provided at the outlet end of the second heat exchanger 502.

[0056] When the self-cooling refrigerant recovery system needs to be evacuated, the first control valve 901 and the third control valve 903 are closed simultaneously to isolate the components between the first control valve 901 and the third control valve 903 from the outside, so that a portion of refrigerant is retained between the first control valve 901 and the third control valve 903. When it is necessary to cool down the second container 2, the first control valve 901 and the third control valve 903 are opened and the second control valve 902 is closed. The refrigerant remaining between the first control valve 901 and the third control valve 903 can immediately participate in the refrigeration work to cool down the second container 2, thereby improving the cooling efficiency of the second container 2 and the refrigerant inside the second container 2.

[0057] Preferably, the first control valve 901, the second control valve 902, and the third control valve 903 are all solenoid valves;

[0058] The self-cooling refrigerant recovery system includes a cooling mode and a recovery mode. In the recovery mode, the first control valve 901 is closed, and the second control valve 902 and the third control valve 903 are open. In the cooling mode, the second control valve 902 is closed, and the first control valve 901 and the third control valve 903 are open.

[0059] A temperature control device can be installed in the self-cooling refrigerant recovery system. The temperature control device is used to collect the temperature inside the second container 2 and control the first control valve 901, the second control valve 902 and the third control valve 903 according to the collected temperature.

[0060] When the temperature control device detects that the temperature of the second container 2 is too high, such as higher than the first preset temperature, the temperature control device controls the first control valve 901 and the third control valve 903 to open, and controls the second control valve 902 to close.

[0061] When the temperature control device detects that the temperature of the second container 2 has dropped to the second preset temperature, the temperature control device controls the first control valve 901 and the third control valve 903 to close, and controls the second control valve 902 to open.

[0062] A timed switching device can also be set to allow the recovery mode and cooling mode to alternate at intervals;

[0063] A quantitative switching device can also be set up to continuously measure the weight of the refrigerant recovered in the second container 2 in the recovery mode. When the weight of the refrigerant in the second container 2 increases by a certain amount, the device switches to the cooling mode and runs for a certain period of time before switching back to the recovery mode.

[0064] Through the above control, the temperature of the second container 2 is linked with the first control valve 901, the second control valve 902 and the third control valve 903, which shortens the reaction time of the self-cooling refrigerant recovery system and improves the working efficiency of the self-cooling refrigerant recovery system.

[0065] The above description is merely 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 within the protection scope of the present invention. The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the protection scope of the present invention.

Claims

1. A self-cooling refrigerant recovery system for recovering refrigerant in a first container (1), characterized in that, include: The compressor (3) has its inlet connected to the outlet of the first container (1); The reversing section (4) includes a reversing inlet, a first reversing outlet, and a second reversing outlet; the reversing inlet is connected to the outlet of the compressor (3); the reversing section (4) is capable of connecting the reversing inlet to the first reversing outlet, or connecting the reversing inlet to the second reversing outlet. The second container (2) has its inlet connected to the second reversing outlet; The inlet of the first heat exchanger (501) is connected to the outlet of the compressor (3), and the outlet of the first heat exchanger (501) is connected to the inlet of the reversing part (4). The throttling device (6) has its inlet connected to the first reversing outlet, and the outlet of the throttling device (6) is connected to the inlet of the compressor (3); The second heat exchanger (502) has its inlet connected to the outlet of the throttling device (6) and is capable of cooling the second container (2).

2. The self-cooling refrigerant recovery system according to claim 1, characterized in that, The self-cooling refrigerant recovery system also includes a first oil separator (701), the inlet of which is connected to the outlet of the first container (1), and the outlet of which is connected to the inlet of the compressor (3).

3. The self-cooling refrigerant recovery system according to claim 2, characterized in that, The outlet of the second heat exchanger (502) is connected to the inlet of the first oil separator (701).

4. The self-cooling refrigerant recovery system according to claim 2, characterized in that, The self-cooling refrigerant recovery system also includes a third heat exchanger (503), the inlet of which is connected to the outlet of the compressor (3), and the outlet of which is connected to the inlet of the first heat exchanger (501); the third heat exchanger (503) is thermally coupled to the first oil separator (701).

5. The self-cooling refrigerant recovery system according to claim 4, characterized in that, The self-cooling refrigerant recovery system also includes a first filter device (801), the inlet of which is connected to the outlet of the first container (1), and the outlet of which is connected to the outlet of the second heat exchanger (502).

6. The self-cooling refrigerant recovery system according to claim 5, characterized in that, The self-cooling refrigerant recovery system also includes a second filter device (802), the inlet of which is connected to the outlet of the first heat exchanger (501), and the outlet of which is connected to the inlet of the reversing unit (4).

7. The self-cooling refrigerant recovery system according to claim 6, characterized in that, The self-cooling refrigerant recovery system also includes a second oil separator (702), the inlet of which is connected to the outlet of the compressor (3), the outlet of which is connected to the inlet of the third heat exchanger (503), and the oil outlet of which is connected to the oil return port of the compressor (3).

8. The self-cooling refrigerant recovery system according to any one of claims 1-7, characterized in that, The reversing part (4) is a three-way pipe, which includes an inlet pipe (401), a circulation outlet pipe (402), and a storage outlet pipe (403); The inlet pipe (401) is connected to the outlet of the first heat exchanger (501), the circulation outlet pipe (402) is connected to the inlet of the throttling device (6), and the storage outlet pipe (403) is connected to the inlet of the second container (2). The circulation outlet pipe (402) is provided with a first control valve (901), and the storage outlet pipe (403) is provided with a second control valve (902).

9. The self-cooling refrigerant recovery system according to claim 8, characterized in that, A third control valve (903) is provided at the outlet end of the second heat exchanger (502).

10. The self-cooling refrigerant recovery system according to claim 9, characterized in that, The first control valve (901), the second control valve (902), and the third control valve (903) are all solenoid valves; The self-cooling refrigerant recovery system includes a cooling mode and a recovery mode; The recovery mode is as follows: the first control valve (901) is closed, and the second control valve (902) and the third control valve (903) are open; The cooling mode is as follows: the second control valve (902) is closed, and the first control valve (901) and the third control valve (903) are open.

Images