Cooling and heating combined supply system based on transcritical carbon dioxide heat pump coupling jet type refrigeration

Abstract

The utility model relates to the technical field of refrigeration and heat supply, in particular to a combined cooling and heating system based on transcritical carbon dioxide heat pump coupling jet type refrigeration, which comprises a compressor, an air cooler connected with the output end of the compressor, an ejector connected with the output end of the air cooler, and a condenser and an evaporator which are respectively connected with the ejector, wherein one output end of the condenser is connected with the input end of the heat exchanger, and the other output end of the condenser is connected with the input end of the evaporator through the throttling valve; the output end of the heat exchanger is connected with the input end of the compressor; the input end of the condenser is connected with the output end of the ejector; the air cooler is connected with the first input end of the ejector, and the output end of the evaporator is connected with the second input end of the ejector. The performance of the coupling system can be improved while cooling and heating are achieved, on one hand, high-temperature heat and low-temperature heat can be provided, on the other hand, medium-temperature heat can be provided, and the comprehensive performance of the system is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of refrigeration and heat supply, especially relates to a cold and heat combined supply system based on transcritical carbon dioxide heat pump coupling ejection type refrigeration. BACKGROUND

[0002] The cold and heat combined supply system is a heat and cold supply system that comprehensively utilizes energy, and the design purpose is to improve energy utilization efficiency as much as possible while meeting the comfortable temperature demand inside the building. The traditional cold and heat supply system usually uses a compression type refrigerator and a boiler, and these devices consume a large amount of electric energy or fuel during operation and emit a large amount of greenhouse gases such as CO2, which has a negative impact on the environment. In order to cope with the dual challenges of environmental protection and energy efficiency, researchers have begun to explore the use of new energy technologies to replace traditional heat and cold supply equipment. Among them, carbon dioxide has environmental protection characteristics of ODP 0 and GWP 1 and excellent thermodynamic properties, so that the transcritical carbon dioxide heat pump system has become a solution that attracts attention. The ejection type refrigeration system is a technology that uses pressure difference and heat exchange to realize energy transfer, which has the advantages of simple structure, high energy efficiency, etc., and has a wide application prospect in the cold supply system.

[0003] For this purpose, for example, the patent with publication number CN118776164A discloses a transcritical carbon dioxide compression-ejection type dual-temperature evaporator cold and heat combined supply system, which is connected by devices such as gas-liquid separators, medium-temperature evaporators, low-temperature evaporators, high-pressure stage compressors, low-pressure stage compressors, gas coolers, ejectors, heat exchangers, medium-temperature throttling valves, and low-temperature throttling valves. The transcritical carbon dioxide compression-ejection type dual-temperature evaporator cold and heat combined supply system can effectively improve the refrigeration performance and energy efficiency, and the transcritical carbon dioxide compression-ejection type dual-temperature evaporator cold and heat combined supply system in the disclosed technology provides two different evaporation temperatures to meet the refrigeration demand of the dual-temperature zone environment, thereby reducing the cost.

[0004] For the above-mentioned disclosed technology, although it can meet the use demand of the dual-temperature zone, it needs a compressor including a high-pressure stage compressor and a low-pressure stage compressor. Based on this, the complexity of the overall system pipeline design is increased, and the use cost of the system is increased.

[0005] Therefore, for the transcritical carbon dioxide cold and heat combined supply system, on the basis of meeting the use demand of different temperature zones, it is also necessary to further optimize the structure of the overall pipeline structure. UTILITY MODEL CONTENT

[0006] The utility model aims at providing a cold and heat combined supply system based on transcritical carbon dioxide heat pump coupling ejection type refrigeration, to solve the technical problems of simplifying the overall pipeline structure and reducing the use cost.

[0007] The cold-heat combined supply system based on transcritical carbon dioxide heat pump coupled ejector refrigeration is achieved by the utility model:

[0008] A cold-heat combined supply system based on transcritical carbon dioxide heat pump coupled ejector refrigeration, comprising: a compressor, an air cooler connected to the output end of the compressor, an ejector connected to the output end of the air cooler, and a condenser and an evaporator connected to the ejector respectively; wherein

[0009] One output end of the condenser is connected to the input end of a heat exchanger, and the other output end of the condenser is connected to the input end of the evaporator through a throttling valve; and the output end of the heat exchanger is connected to the input end of the compressor;

[0010] The input end of the condenser is connected to the output end of the ejector; the air cooler is connected to the first input end of the ejector, and the output end of the evaporator is connected to the second input end of the ejector.

[0011] In the optional implementation of the utility model, carbon dioxide working medium flows among the compressor, air cooler, ejector, condenser, throttling valve and evaporator.

[0012] In the optional implementation of the utility model, the compressor is used to compress low-pressure and low-temperature carbon dioxide gas into high-pressure and high-temperature transcritical carbon dioxide.

[0013] In the optional implementation of the utility model, the air cooler is used to cool high-temperature and high-pressure transcritical carbon dioxide; and the air cooler is also adapted to heat exchange with a medium-temperature water pipe to form high-temperature hot water in the medium-temperature hot water pipe.

[0014] In the optional implementation of the utility model, the heat exchanger is also used to heat and vaporize liquid carbon dioxide by heat exchange with high-temperature hot water.

[0015] In the optional implementation of the utility model, the ejector is adapted to mix high-pressure and high-temperature carbon dioxide gas with low-pressure and low-temperature carbon dioxide gas to form medium-pressure and medium-temperature carbon dioxide fluid.

[0016] In the optional implementation of the utility model, the condenser is used to condense medium-temperature and medium-pressure carbon dioxide fluid into liquid carbon dioxide; and

[0017] The condenser is also adapted to heat exchange with a cooling water pipe to form medium-temperature hot water in the cooling water pipe.

[0018] In optional implementation of the utility model, the liquid carbon dioxide formed by the condenser is divided into two paths, one of which is throttled and depressurized into low-pressure and low-temperature carbon dioxide liquid by the throttle valve, and the low-pressure and low-temperature carbon dioxide liquid is evaporated into low-pressure and low-temperature carbon dioxide gas by absorbing heat after entering the evaporator.

[0019] In optional implementation of the utility model, the evaporator is further adapted to exchange heat with the cold water pipe to form low-temperature cold water from normal-temperature cold water in the cold water pipe.

[0020] In optional implementation of the utility model, the other path of liquid carbon dioxide formed by the condenser is heated by the heat exchanger and high-temperature hot water to reach carbon dioxide gas close to the initial temperature, and then returns to the compressor.

[0021] The above technical scheme is adopted, and the utility model has the following beneficial effects: the cold and heat combined supply system based on the transcritical carbon dioxide heat pump coupled ejector refrigeration of the utility model adopts the cold and heat combined supply system of the natural working medium transcritical carbon dioxide heat pump system coupled ejector refrigeration, realizes the supply of cold and heat while improving the performance of the coupled system, can provide high-temperature heat and low-temperature heat on one hand, can provide medium-temperature heat at the same time, and the comprehensive performance of the system is improved; on the other hand, the ejector recovers a part of throttling loss, and the energy efficiency ratio of the system is improved. In addition, the use of the environmental protection working medium carbon dioxide replaces the traditional refrigerant, reduces the emission of greenhouse gases, at the same time, can provide a high-grade heat source for the ejector refrigeration system, the ejector can recover the expansion work of the transcritical carbon dioxide system, and the system performance is improved. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 Fig. 1 is a structure schematic diagram of the cold and heat combined supply system based on the transcritical carbon dioxide heat pump coupled ejector refrigeration of the utility model.

[0023] In the figure: compressor 1, air cooler 2, ejector 3, condenser 4, heat exchanger 5, throttle valve 6, evaporator 7, heat utilization scene 8, and life heating area 9. DETAILED DESCRIPTION

[0024] In order to make the content of the utility model more easily and clearly understood, the utility model is further described in detail below according to specific embodiments and in combination with the drawings.

[0025] Please refer to Figure 1As shown, the embodiment provides a cold and heat combined supply system based on transcritical carbon dioxide heat pump coupled with ejector refrigeration, which comprises a compressor 1, an air cooler 2 connected with the output end of the compressor 1, an ejector 3 connected with the output end of the air cooler 2, and a condenser 4 and an evaporator 7 connected with the ejector 3 respectively; wherein the ejector 3 realizes refrigeration on the side of the evaporator 7, heat supply on the side of the condenser 4, and simultaneously improves the gas pressure returned to the compressor 1.

[0026] Specifically, one output end of the condenser 4 is connected with the input end of a heat exchanger 5, and the other output end of the condenser 4 is connected with the input end of the evaporator 7 through a throttling valve 6; and the output end of the heat exchanger 5 is connected with the input end of the compressor 1; the input end of the condenser 4 is connected with the output end of the ejector 3; the air cooler 2 is connected with the first input end of the ejector 3, and the output end of the evaporator 7 is connected with the second input end of the ejector 3.

[0027] Based on the above, it should be noted that the compressor 1, the air cooler 2, the ejector 3, the condenser 4, the throttling valve 6 and the evaporator 7 in the embodiment circulate carbon dioxide working medium. The use of the environmentally friendly working medium carbon dioxide replaces the traditional refrigerant and reduces the emission of greenhouse gases.

[0028] More specifically, the compressor 1 of the embodiment is used to compress low-pressure and low-temperature carbon dioxide gas into high-pressure and high-temperature transcritical carbon dioxide. The air cooler 2 is used to cool the high-temperature and high-pressure transcritical carbon dioxide; and the air cooler 2 is also suitable for heat exchange with a medium-temperature water pipe to form high-temperature hot water from medium-temperature hot water in the medium-temperature water pipe. The heat exchanger 5 also uses heat exchange with high-temperature hot water to heat and vaporize liquid carbon dioxide to prevent liquid hammer in the compressor 1. The ejector 3 is suitable for mixing high-pressure and high-temperature carbon dioxide gas with low-pressure and low-temperature carbon dioxide gas to form medium-pressure and medium-temperature carbon dioxide fluid.

[0029] Furthermore, the condenser 4 is used to condense the medium-temperature and medium-pressure carbon dioxide fluid into liquid carbon dioxide; and the condenser 4 is also suitable for heat exchange with a cooling water pipe to form medium-temperature hot water from normal-temperature cold water in the cooling water pipe. The liquid carbon dioxide formed by the condenser 4 is divided into two paths, one of which is throttled and decompressed into low-pressure and low-temperature carbon dioxide liquid by the throttling valve 6, and the low-pressure and low-temperature carbon dioxide liquid absorbs heat to evaporate into low-pressure and low-temperature carbon dioxide gas after entering the evaporator 7. The evaporator 7 is also suitable for heat exchange with the cooling water pipe to form low-temperature cold water from normal-temperature cold water in the cooling water pipe. The other liquid carbon dioxide formed by the condenser 4 is heated by the heat exchanger 5 to reach carbon dioxide gas close to the initial temperature after heat exchange with high-temperature hot water, and then returns to the compressor 1.

[0030] In summary, for the cold and heat combined supply system based on transcritical carbon dioxide heat pump coupled with ejector refrigeration of the embodiment, the specific implementation principle is as follows:

[0031] The low-pressure and low-temperature carbon dioxide gas enters the compressor 1 and is compressed into high-pressure and high-temperature transcritical carbon dioxide; the high-pressure and high-temperature carbon dioxide gas enters the gas cooler and forms high-temperature hot water with the medium-temperature hot water in the medium-temperature water pipe, which can be used for hot water heating, pasteurization or blanching and other heat application scenarios 8; the high-pressure and high-temperature carbon dioxide gas enters the ejector 3, mixes with the low-pressure and low-temperature carbon dioxide gas by injection, forms medium-pressure and medium-temperature carbon dioxide fluid in the mixing chamber, enters the condenser 4, and exchanges heat with the cooling water pipe to form medium-temperature hot water with the normal-temperature cold water in the cooling water pipe, which can be used for heating in the living area 9; one way of liquid carbon dioxide is throttled by the throttle valve 6 to become low-pressure and low-temperature carbon dioxide liquid, which enters the evaporator 7 to absorb heat and evaporate into low-pressure and low-temperature carbon dioxide gas; the evaporator 7 exchanges heat with the cooling water pipe to form low-temperature cold water with the normal-temperature cold water in the cooling water pipe, which can be used for cooling in data centers and the like; the low-pressure and low-temperature carbon dioxide gas is injected into the ejector 3 again, mixes with the high-pressure and high-temperature carbon dioxide gas by injection, forms medium-pressure and medium-temperature carbon dioxide fluid in the mixing chamber, and starts a new cycle; the other way of liquid carbon dioxide exchanges heat with the high-temperature hot water through the heat exchanger 5 to become carbon dioxide gas close to the initial temperature, and then returns to the compressor 1. Therefore, the cold and heat combined supply system based on the transcritical carbon dioxide heat pump coupled with the ejector refrigeration of the embodiment can realize cooling and heating at the same time and improve the performance of the coupled system, which can provide high-temperature heat and low-temperature heat, and can also provide medium-temperature heat, thereby improving the comprehensive performance of the system.

[0032] The above specific embodiments further illustrate the purpose, technical scheme and advantages of the utility model, and it should be understood that the above is only a specific embodiment of the utility model and is not used to limit the utility model, and any modification, equivalent replacement, improvement and the like made within the spirit and principle of the utility model should be included in the protection scope of the utility model.

[0033] In the description of the utility model, it should be understood that the terms indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the indicated device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the utility model.

[0034] In the utility model, unless another definite provision and limitation, the term "mount", "link", "connect", "fix" and so on term should do broad sense understanding, for example, can be fixed connection, also can be detachable connection, or be integrated; can be mechanical connection, also can be electrical connection; can be direct connection, also can indirectly connect through intermediate medium, can be two element internal communication or two element mutual action relation. For ordinary skilled person in the art, can understand the concrete meaning of above-mentioned term in the utility model according to specific circumstances.

[0035] In the utility model, unless another definite provision and limitation, first feature is on or under second feature can include that first and second features are directly contacted, also can include that first and second features are not directly contacted but are contacted through additional feature between them. Moreover, first feature is on, above and on top of second feature includes that first feature is directly above and obliquely above second feature, or just indicates that the horizontal height of first feature is higher than second feature. First feature is under, below and under second feature includes that first feature is directly below and obliquely below second feature, or just indicates that the horizontal height of first feature is less than second feature.

Claims

1. A combined cooling and heating system based on a transcritical carbon dioxide heat pump coupled with jet refrigeration, characterized in that, include: A compressor, an air cooler connected to the output end of the compressor, an ejector connected to the output end of the air cooler, and a condenser and an evaporator respectively connected to the ejector; in One output terminal of the condenser is connected to the input terminal of the heat exchanger, and the other output terminal of the condenser is connected to the input terminal of the evaporator through a throttling valve; and the output terminal of the heat exchanger is connected to the input terminal of the compressor. The input end of the condenser is connected to the output end of the ejector; the air cooler is connected to the first input end of the ejector, and the output end of the evaporator is connected to the second input end of the ejector.

2. The combined cooling and heating system based on a transcritical carbon dioxide heat pump coupled with jet refrigeration according to claim 1, characterized in that, Carbon dioxide is the working fluid that flows between the compressor, air cooler, ejector, condenser, throttle valve and evaporator.

3. The combined cooling and heating system based on a transcritical carbon dioxide heat pump coupled with jet refrigeration according to claim 2, characterized in that, The compressor is used to compress low-pressure, low-temperature carbon dioxide gas into high-pressure, high-temperature transcritical carbon dioxide.

4. The combined cooling and heating system based on a transcritical carbon dioxide heat pump coupled with jet refrigeration according to claim 3, characterized in that, The air cooler is used to cool high-temperature and high-pressure transcritical carbon dioxide; and the air cooler is also suitable for heat exchange with medium-temperature water pipes to transform the medium-temperature hot water in the medium-temperature water pipes into high-temperature hot water.

5. The combined cooling and heating system based on a transcritical carbon dioxide heat pump coupled with jet refrigeration according to claim 4, characterized in that, The heat exchanger also uses heat exchange with high-temperature hot water to heat and vaporize liquid carbon dioxide.

6. The combined cooling and heating system based on a transcritical carbon dioxide heat pump coupled with jet refrigeration according to claim 5, characterized in that, The injector is adapted to mix high-pressure, high-temperature carbon dioxide gas with low-pressure, low-temperature carbon dioxide gas to form a medium-pressure, medium-temperature carbon dioxide fluid.

7. The combined cooling and heating system based on a transcritical carbon dioxide heat pump coupled with jet refrigeration according to claim 6, characterized in that, The condenser is used to condense medium-temperature, medium-pressure carbon dioxide fluid into liquid carbon dioxide; and The condenser is also adapted to exchange heat with the cooling water pipe to transform the ambient temperature cold water in the pipe into medium temperature hot water.

8. The combined cooling and heating system based on a transcritical carbon dioxide heat pump coupled with jet refrigeration according to claim 7, characterized in that, The liquid carbon dioxide formed in the condenser is divided into two streams. One stream of liquid carbon dioxide is throttled and depressurized through a throttling valve to become low-pressure, low-temperature liquid carbon dioxide. This low-pressure, low-temperature liquid carbon dioxide enters the evaporator, absorbs heat, and evaporates into low-pressure, low-temperature gas carbon dioxide.

9. The combined cooling and heating system based on a transcritical carbon dioxide heat pump coupled with jet refrigeration according to claim 8, characterized in that, The evaporator is also adapted to exchange heat with the cold water pipe to transform the room-temperature cold water in the cold water pipe into low-temperature cold water.

10. The combined cooling and heating system based on a transcritical carbon dioxide heat pump coupled with jet refrigeration according to claim 8 or 9, characterized in that, The other stream of liquid carbon dioxide formed by the condenser exchanges heat with the high-temperature hot water through a heat exchanger, reaching a carbon dioxide gas temperature close to the initial temperature, and then returns to the compressor.

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