Cascade refrigeration system and environmental test equipment

Abstract

The utility model discloses a cascade refrigeration system and environmental test equipment. The cascade refrigerating system comprises a high-temperature section R290 system, a low-temperature section R744 system, a heat exchanger and an energy recycling and reusing system. Wherein the high-temperature section R290 system is connected with the heat exchanger and the low-temperature section R744 system, and the low-temperature section R744 system is connected with the heat exchanger; the energy recycling and reusing system is connected with the high-temperature section R290 system and the low-temperature section R744 system. The energy recycling system is used for storing heat released by the system in the system cooling process and providing heat for system heating in the system heating process. The energy recycling system is arranged between the high-temperature-section R290 system and the low-temperature-section R744 system, heat in the cooling process of the systems can be recycled and stored, the stored heat can be recycled when the temperature of the systems rises, and therefore energy waste can be avoided, cost can be reduced, and the environmental protection effect can be improved.

Description

Technical Field

[0001] The utility model relates to the technical field of refrigeration, in particular to a cascade refrigeration system and environmental testing equipment. Background Art

[0002] As the application requirements of environmentally friendly refrigerants become more and more stringent, it is particularly important to use refrigerants with low global warming potential (GWP). Most of the existing cascade refrigeration systems are R23 / R404A cascade systems, and the GWP of R23 / R404A refrigerants is relatively high and cannot meet environmental protection requirements. In addition, the heat exchange of the R23 / R404A cascade system is directly transferred to the air, which is not conducive to environmental protection and causes energy waste. Utility Model Content

[0003] The utility model provides a cascade refrigeration system and environmental testing equipment to provide a more environmentally friendly refrigeration solution, reduce energy waste, and lower costs.

[0004] According to one aspect of the utility model, a cascade refrigeration system is provided, the cascade refrigeration system comprising: a high temperature section R290 system, a low temperature section R744 system, a heat exchanger and an energy recovery and reuse system;

[0005] The high temperature section R290 system is connected to the heat exchanger and the low temperature section R744 system respectively, and the low temperature section R744 system is connected to the heat exchanger; the energy recovery and reuse system is connected to the high temperature section R290 system and the low temperature section R744 system respectively;

[0006] The energy recovery and reuse system is used to store the heat released by the system during the system cooling process, and to provide heat for the system heating process.

[0007] Optionally, the energy recovery and reuse system includes a heat storage module and a heating module; wherein the heat storage module is connected to the high-temperature section R290 system and the heating module respectively; the heating module is connected to the low-temperature section R744 system; the heat storage module is used to store the heat released by the system during the system cooling process, and provide heat to the heating module during the system heating process; the heating module is used to provide heat for system heating during the system heating process.

[0008] Optionally, the heat storage module is a water tank.

[0009] Optionally, the temperature increasing module includes a first heating unit; the first heating unit is respectively connected to the heat storage module and the low temperature section R744 system.

[0010] Optionally, the first heating unit is a temperature-raising surface cooler.

[0011] Optionally, the temperature increasing module further includes a second heating unit; the second heating unit is connected to the first heating unit.

[0012] Optionally, the second heating unit is an electric heater.

[0013] Optionally, the cascade refrigeration system also includes a water system; the high-temperature section R290 system includes at least: an R404A evaporator, a first compressor and an R290 condenser; wherein the R404A evaporator is respectively connected to the heat exchanger, the first compressor and the R290 condenser, the first compressor is respectively connected to the heat exchanger and the R290 condenser, and the R290 condenser is respectively connected to the low-temperature section R744 system, the water system and the energy recovery and reuse system.

[0014] Optionally, the low-temperature section R744 system includes at least: an R744 cooling evaporator, a second compressor and an R744 precooler; wherein the R744 cooling evaporator is respectively connected to the heat exchanger and the second compressor, the second compressor is respectively connected to the heat exchanger and the R744 precooler, and the R744 precooler is respectively connected to the heat exchanger and the high-temperature section R290 system.

[0015] According to another aspect of the present invention, an environmental testing device is provided. The environmental testing device includes the cascade refrigeration system as described in the first aspect.

[0016] The technical solution of the embodiment of the utility model provides a cascade refrigeration system and environmental testing equipment, wherein the cascade refrigeration system includes: a high-temperature section R290 system, a low-temperature section R744 system, a heat exchanger and an energy recovery and reuse system; wherein the high-temperature section R290 system is connected to the heat exchanger and the low-temperature section R744 system respectively, and the low-temperature section R744 system is connected to the heat exchanger; the energy recovery and reuse system is connected to the high-temperature section R290 system and the low-temperature section R744 system respectively; the energy recovery and reuse system is used to store the heat released by the system during the system cooling process, and to provide heat for the system heating process during the system heating process. It can be seen that by setting up the high-temperature section R290 system and the low-temperature section R744 system using low-GWP refrigerants, since the refrigerant pressure of the low-GWP refrigerant is high and environmentally friendly, the cascade refrigeration system has a better refrigeration effect and is more environmentally friendly. In addition, by setting up an energy recovery and reuse system between the high-temperature R290 system and the low-temperature R744 system, the heat generated during the system cooling process can be recovered and stored, and the stored heat can be reused when the system heats up, thereby avoiding energy waste, reducing refrigeration costs, and increasing environmental protection effects.

[0017] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present utility model, nor are they intended to limit the scope of the present utility model. Other features of the present utility model will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 It is a principle structure block diagram of a cascade refrigeration system provided in an embodiment of the utility model;

[0020] Figure 2 It is a principle structure block diagram of another cascade refrigeration system provided in an embodiment of the utility model;

[0021] Figure 3 It is a principle structure block diagram of another cascade refrigeration system provided in an embodiment of the utility model;

[0022] Figure 4 It is a structural schematic diagram of a cascade refrigeration system provided in an embodiment of the utility model;

[0023] Figure 5 This is a schematic diagram of the principle structure of the cooling process of a cascade refrigeration system provided in an embodiment of the utility model;

[0024] Figure 6 It is a schematic diagram of the principle structure of the cooling process of another cascade refrigeration system provided in an embodiment of the utility model;

[0025] Figure 7 It is a schematic diagram of the principle structure of the heating process of a cascade refrigeration system provided in an embodiment of the utility model. DETAILED DESCRIPTION

[0026] In order to enable those skilled in the art to better understand the solution of the utility model, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is only a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the utility model.

[0027] It should be noted that the terms "first", "second", etc. in the specification and claims of the utility model and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the utility model described here can be implemented in an order other than those illustrated or described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0028] Figure 1 This is a principle structure diagram of a cascade refrigeration system provided in an embodiment of the utility model. Figure 1 The cascade refrigeration system includes: a high-temperature section R290 system 100, a low-temperature section R744 system 200, a heat exchanger 300 and an energy recovery and reuse system 400; wherein the high-temperature section R290 system 100 is respectively connected to the heat exchanger 300 and the low-temperature section R744 system 200, and the low-temperature section R744 system 200 is connected to the heat exchanger 300; the energy recovery and reuse system 400 is respectively connected to the high-temperature section R290 system 100 and the low-temperature section R744 system 200; the energy recovery and reuse system 400 is used to store the heat released by the system during the system cooling process, and provide heat for the system heating process.

[0029] The refrigerant of the high temperature section R290 system 100 uses R290 refrigerant, and the refrigerant of the low temperature section R744 system 200 uses R744 refrigerant. The high temperature section R290 system 100 and the low temperature section R744 system 200 are connected to each other through the heat exchanger 300 to form a cascade working cycle.

[0030] Among them, R290 refrigerant and R744 refrigerant have relatively low GWP, high refrigerant pressure and are environmentally friendly. Therefore, the cascade refrigeration system can achieve better refrigeration effect while being more environmentally friendly.

[0031] The heat exchanger 300 may be a plate heat exchanger. The heat exchanger may also be other heat exchangers, which may be configured according to actual conditions and are not specifically limited here.

[0032] In the prior art, the heat of the cascade system cooling process is usually directly released into the air, which can easily cause energy waste and environmental pollution (e.g., exacerbating global warming). To this end, the present embodiment provides a cascade refrigeration system, the refrigerant of the high-temperature section R290 system 100 uses a low-GWP R290 refrigerant, the refrigerant of the low-temperature section R744 system 200 uses a low-GWP R744 refrigerant, and an energy recovery and reuse system 400 is set between the high-temperature section R290 system 100 and the low-temperature section R744 system 200. The energy recovery and reuse system 400 is used to recover and store the heat released by the system during the system cooling process, reducing energy waste and environmental pollution. And the recovered and stored heat is reused during the system heating process to provide heat for the system heating, thereby realizing energy reuse, reducing energy waste, reducing costs, and further increasing environmental protection effects.

[0033] In the technical solution of this embodiment, the implementation process of the cascade refrigeration system is as follows: Figure 1 The cascade refrigeration system includes: a high-temperature section R290 system 100, a low-temperature section R744 system 200, a heat exchanger 300 and an energy recovery and reuse system 400. The refrigerant of the high-temperature section R290 system 100 uses a low-GWP R290 refrigerant, and the refrigerant of the low-temperature section R744 system 200 uses a low-GWP R744 refrigerant. The energy recovery and reuse system 400 is connected to the high-temperature section R290 system 100 and the low-temperature section R744 system 200 respectively. During the system cooling process, the heat released by the high-temperature section R290 system 100 is stored in the energy recovery and reuse system 400. During the system heating process, the heat recovered and stored in the energy recovery and reuse system 400 is reused and provided to the low-temperature section R744 system 200 to provide heat for the system heating, thereby reducing energy waste, realizing energy recycling, reducing costs, and further increasing environmental protection effects.

[0034] The technical solution of this embodiment provides a cascade refrigeration system, which includes: a high-temperature section R290 system, a low-temperature section R744 system, a heat exchanger and an energy recovery and reuse system; wherein the high-temperature section R290 system is connected to the heat exchanger and the low-temperature section R744 system respectively, and the low-temperature section R744 system is connected to the heat exchanger; the energy recovery and reuse system is connected to the high-temperature section R290 system and the low-temperature section R744 system respectively; the energy recovery and reuse system is used to store the heat released by the system during the system cooling process, and provide heat for the system heating process. It can be seen that by setting up the high-temperature section R290 system and the low-temperature section R744 system using low-GWP refrigerants, since the refrigerant pressure of the low-GWP refrigerant is high and environmentally friendly, the cascade refrigeration system has a better refrigeration effect and is more environmentally friendly. In addition, by setting up an energy recovery and reuse system between the high-temperature R290 system and the low-temperature R744 system, the heat generated during the system cooling process can be recovered and stored, and the stored heat can be reused when the system heats up, thereby avoiding energy waste, reducing refrigeration costs, and increasing environmental protection effects.

[0035] Figure 2 It is a principle structure block diagram of another cascade refrigeration system provided in the embodiment of the utility model. Based on the above embodiment, optionally, refer to Figure 2 The energy recovery and reuse system 400 includes a heat storage module 410 and a heating module 420; wherein the heat storage module 410 is respectively connected to the high temperature section R290 system 100 and the heating module 420; the heating module 420 is connected to the low temperature section R744 system 200; the heat storage module 410 is used to store the heat released by the system during the system cooling process, and to provide heat for the heating module 420 during the system heating process; the heating module 420 is used to provide heat for the system heating process.

[0036] Among them, the heat storage module 410 is connected to the high temperature section R290 system, and is used to recycle and store the heat process in the system cooling process, reducing energy waste and environmental pollution. The heating module 420 is connected to the low temperature section R744 system 200, and is used to provide heat for system heating. The heat storage module 410 is also connected to the heating module 420. The heat storage module 410 is also used to provide heat to the heating module 420 during the system heating process, so as to facilitate the heating module 420 to provide heat for the system, thereby realizing the reuse of the recovered and stored heat, thereby reducing energy waste, realizing energy reuse, reducing costs, and increasing environmental protection.

[0037] Optionally, the heat storage module is a water tank.

[0038] The heat storage module is a water tank, in which liquid, such as water, is stored. The heat released by the system during the system cooling process can be stored in a manner of: recycling the heat released by the system to the water tank for heating the temperature of the liquid in the water tank, thereby recycling and storing the heat released by the system.

[0039] In the technical solution of this embodiment, the implementation process of the cascade refrigeration system is as follows: Figure 2 The cascade refrigeration system includes: a high-temperature section R290 system 100, a low-temperature section R744 system 200, a heat exchanger 300, a heat storage module 410 and a heating module 420. The refrigerant of the high-temperature section R290 system 100 uses a low-GWP R290 refrigerant, and the refrigerant of the low-temperature section R744 system 200 uses a low-GWP R744 refrigerant. The heat storage module 410 is connected to the high-temperature section R290 system 100 and the heating module 420, respectively, and the heating module 420 is connected to the low-temperature section R744 system 200. Specifically, during the system cooling process, the heat released by the high-temperature section R290 system 100 is stored in the heat storage module 410, which can reduce energy waste and environmental pollution. During the system heating process, the heat recovered and stored in the heat storage module 410 is reused to provide heat for the heating module 420, thereby facilitating the heating module 420 to provide heat to the low-temperature section R744 system 200 to provide heat for system heating, thereby reducing energy waste, achieving energy recycling, reducing costs, and further increasing environmental protection effects.

[0040] Figure 3 It is a principle structure block diagram of another cascade refrigeration system provided in the embodiment of the utility model. Based on the above embodiment, optionally, refer to Figure 3 The temperature increasing module 420 includes a first heating unit 421; the first heating unit 421 is connected to the heat storage module 410 and the low temperature section R744 system 200 respectively.

[0041] The first heating unit 421 is used to recycle the heat stored in the heat storage module 410 during the system heating process to provide heat for the system heating.

[0042] Optionally, the first heating unit is a temperature-raising surface cooler.

[0043] The temperature-raising surface cooler provided in this embodiment can provide the heat stored in the heat storage module 410 (for example, hot water at a certain temperature) to the system temperature-raising process, thereby providing heat for the system temperature-raising.

[0044] Optionally, continue to refer to Figure 3 The heating module 420 further includes a second heating unit 422 ; the second heating unit 422 is connected to the first heating unit 411 .

[0045] Among them, the second heating unit 422 is used to provide heat for system heating when the heat provided by the heat storage module 410 cannot meet the heat required by the first heating unit (that is, cannot meet the heat required for system heating) during the system heating process, thereby meeting the system needs, ensuring the normal operation of the system, and improving energy utilization.

[0046] Optionally, the second heating unit is an electric heater.

[0047] The specific model of the electric heater can be set according to actual conditions and is not specifically limited here.

[0048] In the technical solution of this embodiment, the implementation process of the cascade refrigeration system is as follows: Figure 3 The cascade refrigeration system includes: a high-temperature section R290 system 100, a low-temperature section R744 system 200, a heat exchanger 300, a heat storage module 410, a first heating unit 421 and a second heating unit 422. The refrigerant of the high-temperature section R290 system 100 uses a low-GWP R290 refrigerant, and the refrigerant of the low-temperature section R744 system 200 uses a low-GWP R744 refrigerant. The heat storage module 410 is connected to the high-temperature section R290 system 100 and the first heating unit 421, respectively, and the first heating unit 421 and the second heating unit 422 are both connected to the low-temperature section R744 system 200. Specifically, during the system cooling process, the heat released by the high-temperature section R290 system 100 is stored in the heat storage module 410, which can reduce energy waste and environmental pollution. During the system heating process, the heat stored in the heat storage module 410 is recycled and reused to provide heat for the first heating unit 421, so that the first heating unit 421 provides heat to the low temperature section R744 system 200 to provide heat for system heating, thereby reducing energy waste, achieving energy recycling, reducing costs, and further increasing environmental protection effects. When the heat provided by the heat storage module 410 cannot meet the heat required by the first heating unit (that is, it cannot meet the heat required for system heating), the second heating unit 422 provides heat for system heating, thereby meeting the needs of the system, ensuring the normal operation of the system, and improving energy utilization.

[0049] Figure 4 Schematic diagram of a cascade refrigeration system provided in an embodiment of the utility model. Figure 4The cascade refrigeration system also includes a water system; the high-temperature section R290 system at least includes: an R404A evaporator, a first compressor and an R290 condenser; wherein the R404A evaporator is respectively connected to the heat exchanger, the first compressor and the R290 condenser, the first compressor is respectively connected to the heat exchanger and the R290 condenser, and the R290 condenser is respectively connected to the low-temperature section R744 system, the water system and the energy recovery and reuse system.

[0050] Among them, the first compressor is a high-temperature side compressor.

[0051] Exemplary, reference Figure 4 , the heat storage module is a water tank, the first heating unit is a temperature riser cooler, and the second heating unit is an electric heater as an example for explanation (the same below, no further details are given).

[0052] Exemplary, reference Figure 4 , the water system includes: cooling tower, cooling tower connected to R290 condenser. Figure 4 The water system also includes water pressure protection, temperature pressure gauge, filter and ball valve.

[0053] Exemplary, reference Figure 4 The energy recovery and reuse system includes a temperature-raising solenoid valve. Exemplarily, the temperature-raising solenoid valve is arranged on the connection line between the water tank and the temperature-raising condenser, and is used to adjust the flow rate of hot water provided by the water tank to the temperature-raising condenser.

[0054] Exemplary, reference Figure 4 The high temperature section R290 system also includes sight glasses, dry filters, check valves, oil separators, gas separators, exhaust temperature detection, several solenoid valves, several pressure gauges and other equipment. For specific equipment and line connections, please refer to Figure 4 .

[0055] Optionally, continue to refer to Figure 4 The low-temperature section R744 system at least includes: an R744 cooling evaporator, a second compressor and an R744 precooler; wherein the R744 cooling evaporator is respectively connected to the heat exchanger and the second compressor, the second compressor is respectively connected to the heat exchanger and the R744 precooler, and the R744 precooler is respectively connected to the heat exchanger and the high-temperature section R290 system.

[0056] Among them, the second compressor is a low-temperature side compressor.

[0057] Exemplary, reference Figure 4 The low temperature section R744 system also includes: expansion valve, pressure sensor, pressure gauge, constant pressure valve, oil separator, return air temperature detection, exhaust temperature detection, several solenoid valves and throttle valves and other equipment. For specific equipment and line connection reference Figure 4 .

[0058] Figure 5 This is a schematic diagram of the principle structure of the cooling process of a cascade refrigeration system provided in an embodiment of the utility model. Figure 6 This is another schematic diagram of the cooling process principle of a cascade refrigeration system provided in an embodiment of the utility model. Figure 7 This is a schematic diagram of the principle structure of the heating process of a cascade refrigeration system provided in an embodiment of the utility model. For example, the condensing temperature of the high-temperature refrigerant R290 refrigerant can be set to 65°C, and the evaporating temperature can be set to -17°C. The condensing temperature of the low-temperature refrigerant R744 refrigerant can be set to -12°C, and the evaporating temperature can be set to -50°C.

[0059] During the system cooling process, since the designed condensing temperature is 65℃, the water temperature in the water tank gradually rises. When the water temperature rises to about 65℃, the heat storage is completed. The operation circuit is as follows: Figure 5 The thick line L1 line is shown. When the water temperature in the water tank rises to about 65℃ and heat storage is completed, the system switches to cooling tower operation, that is, the heat released by the system cooling is output to the cooling tower to release the heat that does not need to be stored and complete the normal condensation cycle. Its operation line is as follows Figure 6 The thick line L2 is shown. During the system heating process, the heat stored in the system cooling process is used to provide heat for the system heating. When the stored heat cannot meet the system demand, the electric heater is used to heat the remaining heat, thereby improving energy utilization. Its operation circuit is as follows Figure 7 The thick line L3 line is shown.

[0060] An embodiment of the utility model further provides an environmental testing device, which includes the cascade refrigeration system provided by any embodiment of the utility model.

[0061] The environmental test equipment consists of a box, a refrigeration system, a water system, and a control system. The box is mainly made of thermal insulation materials. The control system is mainly composed of a touch screen, a PLC and its expansion modules, a temperature sensor, etc. The refrigeration system is mainly composed of a compressor, a condenser, an evaporator and its fan, an electronic expansion valve (or other adjustable throttling elements), etc.

[0062] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be performed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0063] The above specific implementations do not constitute a limitation on the protection scope of the present utility model. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present utility model shall be included in the protection scope of the present utility model.

Claims

1. A cascade refrigeration system, characterized in that: include: High temperature section R290 system, low temperature section R744 system, heat exchanger and energy recovery and reuse system; The high temperature section R290 system is connected to the heat exchanger and the low temperature section R744 system respectively, and the low temperature section R744 system is connected to the heat exchanger; the energy recovery and reuse system is connected to the high temperature section R290 system and the low temperature section R744 system respectively; The energy recovery and reuse system is used to store the heat released by the system during the system cooling process, and to provide heat for the system heating process.

2. The cascade refrigeration system according to claim 1, characterized in that: The energy recovery and reuse system includes a heat storage module and a heating module; wherein the heat storage module is connected to the high-temperature section R290 system and the heating module respectively; the heating module is connected to the low-temperature section R744 system; the heat storage module is used to store the heat released by the system during the system cooling process, and provide heat to the heating module during the system heating process; the heating module is used to provide heat for system heating during the system heating process.

3. The cascade refrigeration system according to claim 2, characterized in that: The heat storage module is a water tank.

4. The cascade refrigeration system according to claim 2, characterized in that: The temperature increasing module comprises a first heating unit; the first heating unit is respectively connected to the heat storage module and the low temperature section R744 system.

5. The cascade refrigeration system according to claim 4, characterized in that: The first heating unit is a temperature-raising surface cooler.

6. The cascade refrigeration system according to claim 4, characterized in that: The temperature increasing module further includes a second heating unit; the second heating unit is connected to the first heating unit.

7. The cascade refrigeration system according to claim 6, characterized in that: The second heating unit is an electric heater.

8. The cascade refrigeration system according to claim 1, characterized in that: It also includes a water system; the high-temperature section R290 system at least includes: an R404A evaporator, a first compressor and an R290 condenser; wherein the R404A evaporator is respectively connected to the heat exchanger, the first compressor and the R290 condenser, the first compressor is respectively connected to the heat exchanger and the R290 condenser, and the R290 condenser is respectively connected to the low-temperature section R744 system, the water system and the energy recovery and reuse system.

9. The cascade refrigeration system according to claim 1, characterized in that: The low-temperature section R744 system at least includes: an R744 cooling evaporator, a second compressor and an R744 precooler; wherein the R744 cooling evaporator is respectively connected to the heat exchanger and the second compressor, the second compressor is respectively connected to the heat exchanger and the R744 precooler, and the R744 precooler is respectively connected to the heat exchanger and the high-temperature section R290 system.

10. An environmental testing device, characterized in that: Comprising the cascade refrigeration system as described in any one of claims 1-9.

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