Advanced environment-friendly refrigerating system
By optimizing the refrigeration system process and configuring a low-GWP mixed working fluid, and utilizing the combination of an ejector and a liquid heat exchanger, the problem of not being able to achieve refrigeration below -40℃ in existing technologies has been solved, achieving a highly efficient and environmentally friendly ultra-low temperature refrigeration effect.
Patent Information
- Application Number
- CN202520314705.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-26
- Publication Date
- 2026-01-13
- Estimated Expiration
- 2035-02-26
AI Technical Summary
Existing single-stage vapor compression refrigeration systems cannot achieve refrigeration below -40°C, and using cascade or multi-stage compression systems increases system complexity and cost.
An advanced and environmentally friendly refrigeration system is adopted, including components such as a compressor, condenser, working fluid pump, ejector, regenerator, expansion valve, gas-liquid separator, evaporator, liquid receiver, and liquid receiver heat exchanger. By optimizing the system process and configuring a low-GWP mixed working fluid, the ejector is used to regulate the pressure and the liquid receiver heat exchanger is used to rationally control the refrigerant and the heat transfer fluid, thereby achieving single-stage vapor compression cryogenic refrigeration.
It enables precise control in different temperature zones, improves system performance, and reduces the impact on global warming.
Smart Images
Figure CN223795512U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of refrigeration systems, and in particular to an advanced and environmentally friendly refrigeration system. Background Technology
[0002] With global warming and rising temperatures, the adoption of new refrigeration technologies using low-GWP environmentally friendly refrigerants is one of the important development directions in the future of the refrigeration and cold storage industry. GWP is an indicator that measures the contribution of greenhouse gases to global warming. GWP environmentally friendly refrigerants refer to those refrigerants with lower GWP values, which have a smaller impact on global warming and are therefore considered a more environmentally friendly choice.
[0003] However, due to limitations in refrigerant properties and compressor operating pressure ratio, current single-stage vapor compression refrigeration systems cannot achieve refrigeration below -40°C. Possible solutions include replacing the system flow with a cascade cycle system or a multi-stage compression system, but this leads to increased system complexity and cost, thus presenting certain drawbacks. Utility Model Content
[0004] The purpose of this invention is to provide an advanced and environmentally friendly refrigeration system to solve the problems mentioned in the background art.
[0005] To achieve the above objectives, this utility model provides the following technical solution: an advanced and environmentally friendly refrigeration system, comprising a compressor, a condenser, a first working fluid pump, a first expansion valve, a first ejector, a regenerator, a second expansion valve, a gas-liquid separator, a third expansion valve, an evaporator, a liquid receiver, a second ejector, a liquid receiver heat exchanger, a first shut-off valve, a second working fluid pump, a cooling heat exchanger, a second shut-off valve, a third shut-off valve, and control components. The compressor outlet is sequentially connected to the condenser and the working fluid pump. The working fluid pump outlet is split into two paths and connected to the expansion valve and the high-temperature inlet of the regenerator, respectively. The expansion valve outlet is connected to the high-pressure inlet of the ejector. The high-temperature outlet of the regenerator is sequentially connected to the expansion valve and the inlet of the gas-liquid separator. After the gas phase outlet of the gas-liquid separator is connected to the ejector outlet, it is then sequentially connected to the low-temperature inlet and outlet of the regenerator, and the pressure... The compressor inlet is connected. The liquid phase outlet of the gas-liquid separator is sequentially connected to the expansion valve, the evaporator refrigeration side inlet and outlet. The gas phase outlet of the gas-liquid separator is connected to the shut-off valve inlet. The shut-off valve outlet is connected to the liquid receiver inlet. The liquid receiver outlet is divided into two paths: one path is connected to the ejector high-pressure inlet, the ejector outlet is connected to the expansion valve outlet and then to the evaporator refrigerant side inlet; the other path of the liquid receiver outlet is connected to the outlet of the cooling heat exchanger via the shut-off valve. The evaporator cooling side outlet is sequentially connected to the working fluid pump and the cooling heat exchanger. The cooling heat exchanger outlet is connected to the shut-off valve and then to the inlet and outlet of the liquid receiver heat exchanger. The liquid receiver heat exchanger outlet is divided into two paths: one path is connected to the ejector low-pressure inlet via the shut-off valve, and the other path is connected to the evaporator cooling side inlet. The liquid receiver heat exchanger is placed inside the liquid receiver.
[0006] Preferably, the interior of the liquid heat exchanger is used for the flow of a cooling medium, the interior of the liquid receiver is used for the flow of a refrigerant, the inner cavity of the liquid heat exchanger and the interior of the liquid receiver are not in communication, and the liquid heat exchanger is used for heat exchange with the liquid receiver.
[0007] Preferably, the control component includes:
[0008] A first temperature sensor is connected to the evaporator;
[0009] The second temperature sensor is connected to the cooling heat exchanger.
[0010] A component concentration sensor is connected to the inlet pipeline of the evaporator;
[0011] The control module has its input terminals electrically connected to a first temperature sensor, a second temperature sensor, and a component concentration sensor, and its output terminals electrically connected to a compressor, a first expansion valve, a first injector, a first shut-off valve, a second shut-off valve, a third shut-off valve, a second expansion valve, and a third expansion valve.
[0012] This utility model also provides a control method for an advanced and environmentally friendly refrigeration system, including the following specific steps: including a rated refrigeration temperature mode. When the rated refrigeration temperature mode is working, first close the first shut-off valve, then close the second shut-off valve, then close the third shut-off valve, and open the first expansion valve.
[0013] The control module connects to the first temperature sensor to collect the evaporator cooling side outlet temperature. When the evaporator cooling side outlet temperature is higher than the set rated cooling temperature, the opening of the second expansion valve and the third expansion valve is gradually reduced, and the compressor speed is increased until the rated cooling effect is achieved. Then, the compressor speed is kept constant, and the opening of the second expansion valve and the third expansion valve remains unchanged.
[0014] Preferably, it includes a low-temperature refrigeration mode. When the low-temperature refrigeration mode is working, the first expansion valve is opened by %, the control module is connected to the first temperature sensor to collect the outlet temperature of the evaporator on the refrigeration side, the control module is connected to the component concentration sensor to collect the refrigerant components after the third expansion valve, and the control module is connected to the second temperature sensor to collect the refrigerant temperature at the outlet of the heat exchanger. When the refrigerant temperature at the outlet of the heat exchanger is higher than or equal to the rated refrigeration temperature.
[0015] Open the third shut-off valve, open the first shut-off valve, close the second shut-off valve, gradually reduce the opening of the second and third expansion valves, increase the compressor speed, and when the component concentration sensor detects that the carbon dioxide content in the refrigerant component after the third expansion valve exceeds a certain percentage, and the refrigerant temperature at the outlet of the heat exchanger reaches the set low-temperature refrigeration temperature, close the third shut-off valve, close the first shut-off valve, maintain the compressor speed unchanged, and keep the opening of the second and third expansion valves unchanged.
[0016] Preferably, including a high-temperature cooling mode, the first expansion valve is opened to %, the control module is connected to the first temperature sensor to collect the outlet temperature of the evaporator on the cooling side, the control module is connected to the component concentration sensor to collect the refrigerant composition after the third expansion valve, and the control module is connected to the second temperature sensor to collect the refrigerant temperature at the outlet of the heat exchanger.
[0017] When the refrigerant temperature at the outlet of the heat exchanger is lower than or equal to the rated refrigeration temperature, open the second shut-off valve, close the third shut-off valve, close the first shut-off valve, gradually increase the opening of the second expansion valve and the third expansion valve, and reduce the compressor speed.
[0018] When the component concentration sensor detects that the carbon dioxide concentration in the refrigerant component after the third expansion valve is below a certain percentage, and the refrigerant temperature at the outlet of the heat exchanger reaches the set high-temperature refrigeration temperature, the second shut-off valve is closed, the compressor speed is kept constant, and the opening of the second and third expansion valves remains unchanged.
[0019] The technical effects and advantages of this utility model are as follows:
[0020] This invention utilizes an advanced and environmentally friendly refrigeration system. By optimizing the system process and configuring a low-GWP mixed working fluid, it achieves a creative effect of single-stage vapor compression cryogenic refrigeration. Through the pressure regulation attribute of the ejector, the expansion work generated during the throttling process is recovered to improve system performance. On the other hand, the flow regulation attributes of the first and second ejectors are used to rationally and effectively control the working fluid of the cooling system and the refrigeration system. At the same time, a liquid heat exchanger is placed in the liquid receiver to condense the high-pressure components rich in low-boiling-point components using the cooling capacity of the cooling fluid. This allows for precise control of the concentration of working fluid components participating in the cycle under different temperature zones. Attached Figure Description
[0021] Figure 1 This is a schematic diagram of the process structure of this utility model.
[0022] In the diagram: 101, compressor; 102, condenser; 103, first working fluid pump; 104, first expansion valve; 105, first ejector; 106, regenerator; 107, second expansion valve; 108, gas-liquid separator; 109, third expansion valve; 110, evaporator; 111, liquid receiver; 112, second ejector; 113, liquid receiver heat exchanger; 114, first shut-off valve; 115, second working fluid pump; 116, cooling heat exchanger; 117, second shut-off valve; 118, third shut-off valve; 201, control module; 202, first temperature sensor; 203, component concentration sensor; 204, second temperature sensor. Detailed Implementation
[0023] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0024] This utility model provides, for example Figure 1The illustrated advanced environmentally friendly refrigeration system includes a compressor 101, a condenser 102, a first working fluid pump 103, a first expansion valve 104, a first ejector 105, a regenerator 106, a second expansion valve 107, a gas-liquid separator 108, a third expansion valve 109, an evaporator 110, a liquid receiver 111, a second ejector 112, a liquid receiver heat exchanger 113, a first shut-off valve 114, a second working fluid pump 115, a secondary cooling heat exchanger 116, a second shut-off valve 117, a third shut-off valve 118, and control components. The compressor 101 compresses the refrigerant. The secondary cooling fluid is a single-component carbon dioxide, and the refrigerant components are a mixed working fluid, selected from any combination of methane, ethane, propane, and isobutane according to the target refrigeration temperature. The outlet of 101 is connected sequentially to condenser 102 and working fluid pump 103. The outlet of working fluid pump 103 is split into two paths, connected to expansion valve 104 and the high-temperature side inlet of regenerator 106 respectively. Regenerator 106 contains two different fluid channels: a high-temperature fluid channel with inlet and outlet, and a low-temperature fluid channel with inlet and outlet. Heat exchange occurs between the high-temperature and low-temperature fluid channels through conduction, convection, and radiation, without mass exchange. The refrigerant component concentrations corresponding to the two fluid channels inside regenerator 106 are the same. The outlet of expansion valve 104 is connected to the high-pressure inlet of ejector 105. The high-temperature outlet of regenerator 106 is connected sequentially to expansion valve 107 and the inlet of gas-liquid separator 108. The gas phase outlet of gas-liquid separator 108 is connected to the ejector... After being connected to the outlet of unit 105, it is then connected in sequence to the low-temperature side inlet and outlet of regenerator 106 and the inlet of compressor 101. The liquid phase outlet of gas-liquid separator 108 is connected in sequence to expansion valve 109 and the refrigeration side inlet and outlet of evaporator 110. The gas phase outlet of gas-liquid separator 108 is connected to the inlet of shut-off valve 118. The outlet of shut-off valve 118 is connected to the inlet of liquid receiver 111. The outlet of liquid receiver 111 is split into two paths: one path is connected to the high-pressure inlet of ejector 112, and the outlet of ejector 112 is connected to the outlet of expansion valve 109 and then to the refrigerant side inlet of evaporator 110. The other path of liquid receiver 111 outlet is connected to the outlet of heat exchanger 116 via shut-off valve 117. The heat exchanger outlet of evaporator 110 is connected in sequence to working fluid pump 115 and heat exchanger 116. 6. The evaporator 110 includes two different fluid channels: a refrigeration-side fluid channel with inlet and outlet, and a cooling-side fluid channel with inlet and outlet. Heat exchange occurs between the refrigeration-side and cooling-side fluid channels via conduction, convection, and radiation; no mass exchange occurs. The refrigerant components flow in the refrigeration-side fluid channel and its inlet and outlet, while the cooling-side fluid channel and its inlet and outlet flow in the cooling-side fluid channel. The outlet of the cooling-side heat exchanger 116 is connected to the shut-off valve 117, and then to the inlet and outlet of the liquid receiver heat exchanger 113. The outlet of the liquid receiver heat exchanger 113 is divided into two paths: one path connects to the low-pressure inlet of the ejector 112 via the shut-off valve 114, and the other path connects to the cooling-side inlet of the evaporator 110.The liquid storage heat exchanger 113 is placed inside the liquid storage tank 111.
[0025] Furthermore, the liquid heat exchanger 113 is connected to the interior of the liquid receiver 111. The interior of the liquid heat exchanger 113 is used for the flow of the refrigerant, and the interior of the liquid receiver 111 is used for the flow of the refrigerant. The interior of the liquid heat exchanger 113 is not in communication with the interior of the liquid receiver 111, and there is no mass exchange between the liquid heat exchanger 113 and the liquid receiver 111. The liquid heat exchanger 113 is used for heat exchange with the liquid receiver 111.
[0026] Furthermore, the control components include a control module 201, a first temperature sensor 202, a component concentration sensor 203, and a second temperature sensor 204. The first temperature sensor 202 is connected to the evaporator 110, the second temperature sensor 204 is connected to the heat exchanger 116, and the component concentration sensor 203 is connected to the inlet pipeline of the evaporator 110. The input terminal of the control module 201 is electrically connected to the first temperature sensor 202, the second temperature sensor 204, and the component concentration sensor 203. The output terminal of the control module 201 is electrically connected to the compressor 101, the first expansion valve 104, the first ejector 105, the first shut-off valve 114, the second shut-off valve 117, the third shut-off valve 118, the second expansion valve 107, and the third expansion valve 109.
[0027] Working principle of this utility model:
[0028] Including the rated cooling temperature mode, the cooling temperature range is -20℃ to -40℃. According to the pre-defined refrigerant composition, the target rated cooling temperature is determined. When the rated cooling temperature mode is working, the first shut-off valve 114 is closed, the second shut-off valve 117 is closed, the third shut-off valve 118 is closed, and the first expansion valve 104 is opened to 50%.
[0029] The control module 201 is connected to the first temperature sensor 202 to collect the cooling side outlet temperature of the evaporator 110. When the cooling side outlet temperature of the evaporator 110 is higher than the set rated cooling temperature, the opening of the second expansion valve 107 and the third expansion valve 109 is gradually reduced, and the speed of the compressor 101 is increased until the cooling effect of the rated temperature is achieved. Then, the speed of the compressor 101 is kept constant, and the opening of the second expansion valve 107 and the third expansion valve 109 remains unchanged.
[0030] It includes a low-temperature refrigeration mode with a refrigeration range of -80℃ to -40℃. Carbon dioxide, the refrigerant in the cooling process, is introduced into the refrigeration process. By increasing the low-temperature refrigerant components participating in the circulation of the refrigeration process, a low-temperature refrigeration effect lower than the rated refrigeration temperature is achieved. When the low-temperature refrigeration mode is working, the first expansion valve 104 is opened to 100%. The control module 201 is connected to the first temperature sensor 202 to collect the refrigeration side outlet temperature of the evaporator 110. The control module 201 is connected to the component concentration sensor 203 to collect the refrigerant components after the third expansion valve 109. The control module 201 is connected to the second temperature sensor 204 to collect the refrigerant temperature at the outlet of the cooling heat exchanger 116. When the refrigerant temperature at the outlet of the cooling heat exchanger 116 is higher than or equal to the rated refrigeration temperature.
[0031] Open the third shut-off valve 118, open the first shut-off valve 114, close the second shut-off valve 117, gradually reduce the opening of the second expansion valve 107 and the third expansion valve 109, and increase the speed of the compressor 101. When the component concentration sensor 203 detects that the carbon dioxide in the refrigerant component after the third expansion valve 109 exceeds 15%, and the refrigerant temperature at the outlet of the heat exchanger 116 reaches the set low-temperature refrigeration temperature, close the third shut-off valve 118, close the first shut-off valve 114, maintain the speed of the compressor 101 unchanged, and keep the opening of the second expansion valve 107 and the third expansion valve 109 unchanged.
[0032] It includes a high-temperature refrigeration mode with a refrigeration range of -20℃ to 0℃. Through the second ejector 112 and the liquid heat exchanger 113, the gaseous low-temperature refrigerant rich in carbon dioxide in the refrigeration process is extracted to the cooling process. By reducing the low-temperature refrigerant components that participate in the circulation of the refrigeration process, a higher refrigeration effect than the rated refrigeration temperature is achieved. The first expansion valve 104 is opened to 50%. The control module 201 is connected to the first temperature sensor 202 to collect the refrigeration side outlet temperature of the evaporator 110. The control module 201 is connected to the component concentration sensor 203 to collect the refrigerant components after the third expansion valve 109. The control module 201 is connected to the second temperature sensor 204 to collect the refrigerant temperature at the outlet of the cooling heat exchanger 116.
[0033] When the refrigerant temperature at the outlet of the heat exchanger 116 is lower than or equal to the rated refrigeration temperature, open the second shut-off valve 117, close the third shut-off valve 118, close the first shut-off valve 114, gradually increase the opening of the second expansion valve 107 and the third expansion valve 109, and reduce the speed of the compressor 101.
[0034] When the component concentration sensor 203 detects that the carbon dioxide concentration in the refrigerant component after the third expansion valve 109 is less than 1%, and the refrigerant temperature at the outlet of the heat exchanger 116 reaches the set high-temperature refrigeration temperature, the second shut-off valve 117 is closed, the compressor 101 speed is kept constant, and the opening of the second expansion valve 107 and the third expansion valve 109 remains unchanged.
[0035] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.
Claims
1. An advanced environmentally friendly refrigeration system characterized by, The system comprises a compressor (101), a condenser (102), a first working medium pump (103), a first expansion valve (104), a first ejector (105), a regenerator (106), a second expansion valve (107), a gas-liquid separator (108), a third expansion valve (109), an evaporator (110), a liquid accumulator (111), a second ejector (112), a liquid accumulator heat exchanger (113), a first stop valve (114), a second working medium pump (115), a cooling medium heat exchanger (116), a second stop valve (117), a third stop valve (118) and a control assembly, the outlet of the compressor (101) is connected with the condenser (102) and the first working medium pump (103) in sequence, the outlet of the first working medium pump (103) is connected with the first expansion valve (104) and the high-temperature side inlet of the regenerator (106) in two ways, the outlet of the first expansion valve (104) is connected with the high-pressure inlet of the first ejector (105), the high-temperature outlet of the regenerator (106) is connected with the second expansion valve (107) and the inlet of the gas-liquid separator (108) in sequence, the gas-phase outlet of the gas-liquid separator (108) is connected with the outlet of the first ejector (105), and then is connected with the low-temperature side inlet and outlet of the regenerator (106) and the inlet of the compressor (101) in sequence, the liquid-phase outlet of the gas-liquid separator (108) is connected with the third expansion valve (109), the refrigeration side inlet and outlet of the evaporator (110) in sequence, the gas-phase outlet of the gas-liquid separator (108) is connected with the inlet of the third stop valve (118), the outlet of the third stop valve (118) is connected with the inlet of the liquid accumulator (111), the outlet of the liquid accumulator (111) is connected with the high-pressure inlet of the second ejector (112) in one way, the outlet of the second ejector (112) is connected with the outlet of the third expansion valve (109) and then is connected with the refrigerant side inlet of the evaporator (110), the outlet of the liquid accumulator (111) is connected with the outlet of the cooling medium heat exchanger (116) through the second stop valve (117) in another way, the cooling side outlet of the evaporator (110) is connected with the second working medium pump (115) and the cooling medium heat exchanger (116) in sequence, the outlet of the cooling medium heat exchanger (116) is connected with the second stop valve (117) and then is connected with the inlet and outlet of the liquid accumulator heat exchanger (113), the outlet of the liquid accumulator heat exchanger (113) is connected with the low-pressure inlet of the second ejector (112) through the first stop valve (114) in one way and is connected with the cooling side inlet of the evaporator (110) in another way, and the liquid accumulator heat exchanger (113) is placed in the liquid accumulator (111).
2. An advanced environmentally friendly refrigeration system as claimed in claim 1 wherein, The inside of the liquid accumulator heat exchanger (113) is used for flowing cooling medium, the inside of the liquid accumulator (111) is used for flowing refrigerant, the inner cavity of the liquid accumulator heat exchanger (113) and the inside of the liquid accumulator (111) are not communicated with each other, and the liquid accumulator heat exchanger (113) is used for heat exchange with the liquid accumulator (111).
3. An advanced environmentally friendly refrigeration system as claimed in claim 1 wherein, The control assembly comprises: a first temperature sensor (202) connected to the evaporator (110). A second temperature sensor (204) connected to the cold heat exchanger (116); A component concentration sensor (203) connected to the evaporator (110) inlet end pipeline; A control module (201), the input end of the control module (201) is electrically connected with the first temperature sensor (202), the second temperature sensor (204) and the component concentration sensor (203), and the output end of the control module (201) is electrically connected with the compressor (101), the first expansion valve (104), the first ejector (105), the first stop valve (114), the second stop valve (117), the third stop valve (118), the second expansion valve (107) and the third expansion valve (109).