Mixed refrigerant as well as additive, preparation method and application thereof

Abstract

The invention provides a mixed refrigerant as well as an additive, a preparation method and application thereof, and belongs to the technical field of refrigerants, the mixed refrigerant comprises the following components in parts by mass: a, 75 parts of combustible components including R290 and R1150; and b, a non-flammable component, the non-flammable component comprises R245fa, R23 and R728, and the non-flammable component is 210 to 265 parts by mass. According to the mixed refrigerant disclosed by the invention, combustible components and incombustible components are reasonably proportioned, and ethylene glycol, ethylene carbonate and propylene carbonate are added as additives, so that the performance of the refrigerant is remarkably improved. The refrigerant has the advantages of being excellent in environmental protection property, low in circulating energy consumption, high in low-temperature performance, good in temperature stability, high in recovery capacity and the like, is suitable for refrigeration equipment such as ultralow-temperature refrigerators, refrigeration houses and air conditioners, and has wide market prospects.

Description

Technical Field

[0001] The present invention belongs to the technical field of refrigerants, and in particular relates to a mixed refrigerant and an additive thereof, a preparation method and an application thereof. Background Art

[0002] As global environmental problems intensify, traditional refrigerants are gradually being eliminated from the market due to high global warming potential (GWP), ozone depletion potential (ODP) and low energy efficiency. Therefore, the development of an environmentally friendly, efficient and safe mixed refrigerant has become an important issue in the field of refrigeration technology.

[0003] Although the commonly used refrigerants on the market, such as R410A and R32, have reduced the GWP value to a certain extent, they still have the following problems:

[0004] Some refrigerants are flammable or non-flammable and cannot meet the needs of different application scenarios;

[0005] The operating temperature range of the refrigerant is limited and it is difficult to adapt to a wide temperature environment;

[0006] The high viscosity of the refrigerant results in increased compressor power consumption and lower energy efficiency;

[0007] The critical temperature of the refrigerant is low, which limits its liquid refrigeration performance.

[0008] Therefore, there is an urgent need to develop a mixed refrigerant that can have a wider operating temperature range, lower viscosity and higher energy efficiency while ensuring environmental protection. Summary of the invention

[0009] In order to solve the above technical problems, the present invention provides a mixed refrigerant and a preparation method and application thereof, which specifically include the following contents:

[0010] An additive for a mixed refrigerant, characterized in that it is composed of the following substances in percentage by mass:

[0011] 20-35% ethylene glycol,

[0012] 65-80% ethylene carbonate and / or propylene carbonate.

[0013] As a further preference, the additive includes 25% ethylene glycol, 50% ethylene carbonate and 25% propylene carbonate, calculated in mass percentage.

[0014] By using ethylene glycol in combination with ethylene carbonate and propylene carbonate, the critical temperature of the refrigerant can be increased while ensuring a low viscosity, thereby ensuring that the refrigerant maintains liquid refrigeration performance while having a wider operating temperature range; the power consumption of the compressor can be reduced, with significant energy-saving effects.

[0015] The present invention also provides a mixed refrigerant, comprising:

[0016] a combustible component, the combustible component comprises R290 and R1150, wherein the combustible component is 75 parts by mass;

[0017] b. non-combustible components, the non-combustible components comprising R245fa, R23 and R728, wherein the non-combustible components are 210 to 265 parts by mass;

[0018] It is characterized in that it also includes additives, and the additives are composed of the following substances in percentage by mass:

[0019] 20-35% ethylene glycol,

[0020] 65-80% ethylene carbonate and / or propylene carbonate;

[0021] The content of the additive in the mixed refrigerant is 0.1%-15% of the total mass of the mixed refrigerant.

[0022] As a further preference, the additive is composed of the following substances in percentage by mass: 25% ethylene glycol, 50% ethylene carbonate and 25% propylene carbonate.

[0023] As a further preference, the ODP value of the mixed refrigerant is 0, and the GWP value of the mixed refrigerant is ≤150.

[0024] The present invention also provides a method for preparing a mixed refrigerant, characterized in that the mixed refrigerant is obtained by the following steps:

[0025] (1) R290, R1150, R245fa, R23 and R728 are added to a first reactor in proportion and mixed to prepare a main refrigerant; the mass ratio of R290, R1150, R245fa, R23 and R727 is: R290: R1150: R245fa: R23: R728 = 25-35: 40-50: 55-65: 85-95: 75-85; wherein the total mass of R290, R1150, R245fa, R23 and R728 is 500g;

[0026] (2) Adding ethylene glycol, ethylene carbonate and propylene carbonate into an ethylene glycol carbonate reactor in proportion to prepare an additive; in terms of mass percentage, the ethylene glycol is 25%, the ethylene carbonate is 50% and the propylene carbonate is 25%; wherein the total mass of the additive is 50 g;

[0027] (3) Adding the products prepared in step (1) and step (2) into a second reactor and stirring them evenly to obtain a mixed refrigerant, wherein the viscosity of the refrigerant is less than 100 mm² / s.

[0028] The present invention also provides a device for using the above-mentioned mixed refrigerant or the mixed refrigerant prepared by the preparation method in the refrigeration cycle system when operating the refrigeration cycle system, adopting two sets of refrigerant circulation circuits, and using the pressurized high-temperature refrigerant gas to increase the enthalpy of the low-pressure and low-temperature refrigerant at the front end of the refrigeration to compensate for the insufficient heating capacity of the system caused by the low quality of the heat source under partial load conditions. The two sets of circuits are matched by a mixer and a throttle valve group to ensure that the thermal parameters of the system refrigerant circulation circuit can still match the heat source under partial load conditions, thereby ensuring the reliability and efficiency of the refrigeration system.

[0029] The two refrigerant circulation circuits are matched with the mixer and throttle valve group, as follows:

[0030] The refrigerant gas of the high temperature circuit comes from the compressor outlet with higher pressure and temperature. Design an independent condenser to cool the refrigerant gas of the high temperature circuit and partially condense it into liquid.

[0031] The refrigerant liquid of the low temperature circuit comes from the evaporator outlet and is in a low pressure and low temperature state. An independent throttle valve is designed to adjust the refrigerant flow of the low temperature circuit.

[0032] The gaseous refrigerant in the high-temperature circuit and the liquid refrigerant in the low-temperature circuit are connected to the mixer through pipes. The selection of the mixer needs to consider a good mixing effect to ensure that the refrigerants in the two states are fully mixed and the overall enthalpy value is increased.

[0033] A throttle valve group is installed after the mixer to adjust the flow and pressure of the mixed refrigerant.

[0034] The throttle valve group should be adjusted according to the load changes of the system to ensure that the refrigerant circulation volume of the high-temperature circuit and the low-temperature circuit matches.

[0035] After the mixed refrigerant passes through the throttle valve group to reduce the pressure, it enters the evaporator to absorb heat and evaporate into gas. The gaseous refrigerant then enters the compressor to complete the cycle.

[0036] In the control part, sensors need to be installed to monitor the temperature, pressure and flow parameters of key points. The controller is used to adjust the opening of the throttle valve and the operating status of the compressor according to real-time data to ensure that the system remains efficient and stable under different loads.

[0037] The two refrigerant circulation loops work together with the mixer and throttle valve group to effectively improve the heating capacity and operating efficiency of the system, especially under partial load conditions, ensuring the reliability and efficiency of the system.

[0038] The mixed refrigerant of the present invention has the following significant advantages:

[0039] Excellent environmental protection: The ODP value of the mixed refrigerant is 0, and the GWP value is ≤150, which meets the environmental protection requirements;

[0040] High-efficiency refrigeration: low cycle energy consumption, energy consumption is 15.05 kW·h / 24h (ambient temperature 25℃, test model 588D), the operating ratio is 44.3% for -80℃ cycle;

[0041] Wide temperature performance: low temperature capability ≤ -100℃, cooling time to -80℃ is 178min, meeting ultra-low temperature requirements;

[0042] Temperature stability: The temperature fluctuation is 4.9, the uniformity is 3.3, the instantaneous temperature range of all points is -77~-83℃, and the temperature distribution is uniform;

[0043] Rapid recovery capability: In the door opening test, the average temperature in the box recovered to -80℃ 42 minutes after the door was opened.

[0044] Power-off recovery performance: After power off, it takes 42 minutes for the average temperature to return to -70°C, 99 minutes to -60°C, 169 minutes to -50°C, and 256 minutes to -40°C.

[0045] The mixed refrigerant of the present invention significantly improves the performance of the refrigerant by rationally mixing the combustible component and the non-combustible component and adding ethylene glycol, ethylene carbonate and propylene carbonate as additives. The refrigerant has the advantages of excellent environmental protection, low cycle energy consumption, strong low temperature performance, good temperature stability, strong recovery ability, etc., and is suitable for refrigeration equipment such as ultra-low temperature refrigerators, cold storages, air conditioners, etc., and has broad market prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 is a process flow chart of the preparation method in Example 2 of the present invention;

[0047] Figure 2 Schematic diagram of two refrigerant circulation circuits of a refrigeration device in Example 3 of the present invention; DETAILED DESCRIPTION

[0048] In order to make the technical means, creative features, objectives and effects of the present invention easy to understand, the present invention is further described below in conjunction with specific embodiments, but the following embodiments are only preferred embodiments of the present invention, not all. Based on the embodiments in the implementation mode, other embodiments obtained by those skilled in the art without creative work are all within the scope of protection of the present invention.

[0049] The specific embodiments of the present invention are described below with reference to the accompanying drawings.

[0050] Example 1

[0051] The mass composition ratio of mixed refrigerants containing additives is as follows:

[0052] R290:R1150:R245fa:R23:R728=30:45:60:90:80; total mass is 500g;

[0053] The total amount of additives added is 50 g, including 12.5 g of ethylene glycol, 25 g of ethylene carbonate and 12.5 g of propylene carbonate.

[0054] Preparation methods, such as Figure 1 shown.

[0055] R290, R1150, R245fa, R23 and R728 are added to the first reactor in proportion, and stirred and mixed to prepare a main refrigerant;

[0056] Adding ethylene glycol, ethylene carbonate and propylene carbonate into an ethylene glycol carbonate reactor in proportion to prepare an additive;

[0057] The main refrigerant and the additive are mixed and stirred evenly to prepare a mixed refrigerant, and the viscosity of the refrigerant is 85 mm2 / s.

[0058] Comparative Example 1

[0059] Mixed refrigerant (model 588D), mass group distribution ratio is as follows:

[0060] R290: R1150: R245fa: R23: R728 = 30: 45: 60: 90: 80; total mass is 500g

[0061] Preparation method

[0062] R290, R1150, R245fa, R23 and R728 were added into the first reactor in proportion, stirred and mixed to obtain a mixed refrigerant, and the viscosity of the mixed refrigerant was 92 mm² / s.

[0063] Performance Testing

[0064]

[0065] Table 1

[0066] Performance test (test conditions: Example 1 is the same as Comparative Example 1)

[0067]

[0068] Table 2

[0069] Table 1 is a performance test data table of comparative example 1, and Table 2 is a performance test data comparison table of embodiment 1 and comparative example 1. It can be seen from Table 1 and Table 2 that:

[0070] By adding ethylene glycol, ethylene carbonate and propylene carbonate, the mixed refrigerant of Example 1 is superior to that of Comparative Example 1 in multiple performance indicators, as shown in the following:

[0071] Lower viscosity and better fluidity further reduce energy consumption;

[0072] Stronger low temperature performance and faster cooling speed;

[0073] Higher temperature uniformity and stability;

[0074] Stronger power failure recovery capability and door opening test performance.

[0075] These improvements show that the addition of additives significantly improves the overall performance of the refrigerant, making it more advantageous in application scenarios such as ultra-low temperature refrigerators and cold storage, further verifying the superiority and market potential of mixed refrigerants containing additives.

[0076] Example 2

[0077] A refrigeration device uses the mixed refrigerant of Example 1 in a refrigeration cycle system and adopts two sets of refrigerant circulation circuits. The pressurized high-temperature refrigerant gas is used to increase the enthalpy of the low-pressure and low-temperature refrigerant at the front end of the refrigeration to make up for the shortcoming of insufficient system heating capacity caused by the low quality of the heat source under partial load conditions. The two sets of circuits are matched by a mixer and a throttle valve group to ensure that the thermal parameters of the system refrigerant circulation circuit can still match the heat source under partial load conditions, thereby ensuring the reliability and high efficiency of the refrigeration system.

[0078] like Figure 2 As shown, the two refrigerant circulation circuits are matched with the mixer and throttle valve group, as follows:

[0079] The refrigerant gas of the high temperature circuit comes from the compressor outlet with higher pressure and temperature. Design an independent condenser to cool the refrigerant gas of the high temperature circuit and partially condense it into liquid.

[0080] The refrigerant liquid of the low temperature circuit comes from the evaporator outlet and is in a low pressure and low temperature state. An independent throttle valve is designed to adjust the refrigerant flow of the low temperature circuit.

[0081] The gaseous refrigerant in the high-temperature circuit and the liquid refrigerant in the low-temperature circuit are connected to the mixer through pipes. The selection of the mixer needs to consider a good mixing effect to ensure that the refrigerants in the two states are fully mixed and the overall enthalpy value is increased.

[0082] A throttle valve group is installed after the mixer to adjust the flow and pressure of the mixed refrigerant.

[0083] The throttle valve group should be adjusted according to the load changes of the system to ensure that the refrigerant circulation volume of the high-temperature circuit and the low-temperature circuit matches.

[0084] After the mixed refrigerant passes through the throttle valve group to reduce the pressure, it enters the evaporator to absorb heat and evaporate into gas. The gaseous refrigerant then enters the compressor to complete the cycle.

[0085] In the control part, sensors are installed to monitor the temperature, pressure and flow parameters of key points. The controller is used to adjust the opening of the throttle valve and the operating status of the compressor according to real-time data to ensure that the system remains efficient and stable under different loads.

[0086] The two refrigerant circulation loops work together with the mixer and throttle valve group to effectively improve the heating capacity and operating efficiency of the system, especially under partial load conditions, ensuring the reliability and efficiency of the system.

[0087]

[0088] Table 3

[0089] Table 3 is the comparative test data of the device of Example 2 and the traditional single-loop device. It can be seen from Table 3 that:

[0090] 1. Advantages of dual circuit design:

[0091] Enthalpy-increasing heating: The refrigerant in the low-temperature circuit is heated by enthalpy-increasing the refrigerant gas in the high-temperature circuit, which makes up for the low quality of the heat source under partial load conditions and significantly improves the heating capacity of the system.

[0092] Thermal parameter matching: The two circuits work together through the mixer and throttle valve group to ensure that the thermal parameters of the refrigerant circulation circuit match the heat source, optimizing the system operation efficiency.

[0093] Significant energy-saving effect: Experimental data show that while the heating capacity is increased, the power consumption of the compressor is reduced, and the energy-saving effect is significantly better than the traditional single-circuit system.

[0094] 2. Synergistic effect of mixed refrigerants:

[0095] The mixed refrigerant (containing additives) of Example 1 is superior to the traditional refrigerant in low temperature performance and thermodynamic properties. It has a lower viscosity (85 mm² / s) and better fluidity, further improving the overall performance of the system.

[0096] The mixed refrigerant has a shorter low-temperature start-up time and can reach the set temperature in a short time. It is particularly suitable for application scenarios such as ultra-low temperature refrigerators and cold storage.

[0097] 3. Improved system stability:

[0098] The dual-circuit design ensures that the system can operate stably under different load conditions through the coordinated work of the mixer and the throttle valve group. Experimental data shows that the heating capacity of the traditional single-circuit system drops significantly under partial load conditions, while this device shows higher stability and reliability.

[0099] 4. Environmental adaptability and flexibility:

[0100] The device can adapt to a wider range of ambient temperatures, especially in low-temperature conditions. Its improved low-temperature performance makes it more advantageous for use in extreme environments.

[0101] 5. Actual application scenario verification

[0102] Ultra-low temperature refrigerator: Using this device in an ultra-low temperature refrigerator can quickly reduce the temperature to below -80°C and maintain a stable low temperature environment. Experimental data shows that the device performs well during low-temperature startup and operation, with small temperature fluctuations and good uniformity.

[0103] Cold storage: When the device is applied in cold storage, the system can operate efficiently under partial load conditions, significantly reducing energy consumption. The operation data of the cold storage shows that the system heating capacity and operating efficiency are better than traditional systems, with significant energy-saving effects.

[0104] Through the verification of experimental data and actual application scenarios, the device has shown significant advantages in refrigeration efficiency, energy saving effect, low temperature performance and system stability. Its dual-circuit design and the synergistic effect of mixed refrigerants make up for the shortcomings of traditional refrigeration systems under partial load conditions and have broad application prospects.

[0105] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and descriptions are only preferred examples of the present invention and are not intended to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. An additive for a mixed refrigerant, characterized in that: It is composed of the following substances in percentage by mass: 20-35% ethylene glycol 65-80% ethylene carbonate and / or propylene carbonate.

2. The additive according to claim 1, characterized in that The additives include 25% ethylene glycol, 50% ethylene carbonate and 25% propylene carbonate, calculated by mass percentage.

3. A mixed refrigerant comprising: a combustible component, the combustible component comprises R290 and R1150, wherein the combustible component is 75 parts by mass; b. non-combustible components, the non-combustible components comprising R245fa, R23 and R728, wherein the non-combustible components are 210 to 265 parts by mass; It is characterized in that it also includes additives, and the additives are composed of the following substances in percentage by mass: 20-35% ethylene glycol 65-80% ethylene carbonate and / or propylene carbonate The content of the additive in the mixed refrigerant is 0.1%-15% of the total mass of the mixed refrigerant.

4. The mixed refrigerant according to claim 3, characterized in that: The additive is composed of the following substances in percentage by mass: 25% ethylene glycol, 50% ethylene carbonate and 25% propylene carbonate.

5. The mixed refrigerant according to claim 3, characterized in that: The ODP value of the mixed refrigerant is 0, and the GWP value of the mixed refrigerant is ≤150.

6. A method for preparing a mixed refrigerant, characterized in that: Obtained by the following steps: (1) R290, R1150, R245fa, R23 and R728 are added to a first reactor in proportion and mixed to prepare a main refrigerant; the mass ratio of R290, R1150, R245fa, R23 and R727 is: R290: R1150: R245fa: R23: R728 = 25-35: 40-50: 55-65: 85-95: 75-85; wherein the total mass of R290, R1150, R245fa, R23 and R728 is 500g; (2) Adding ethylene glycol, ethylene carbonate and propylene carbonate into an ethylene glycol carbonate reactor in proportion to prepare an additive; in terms of mass percentage, the ethylene glycol is 25%, the ethylene carbonate is 50% and the propylene carbonate is 25%; wherein the total mass of the additive is 50 g; (3) Adding the products prepared in step (1) and step (2) into a second reactor and stirring them evenly to obtain a mixed refrigerant, wherein the viscosity of the refrigerant is less than 100 mm² / s.

7. A device for using the mixed refrigerant according to any one of claims 3 to 5 or the mixed refrigerant prepared by the preparation method according to claim 6 in a refrigeration cycle system when operating the refrigeration cycle system, using two sets of refrigerant circulation loops, and using the pressurized high-temperature refrigerant gas to increase the enthalpy of the low-pressure and low-temperature refrigerant at the front end of the refrigeration to compensate for the insufficient heating capacity of the system caused by the low quality of the heat source under partial load conditions. The two sets of loops are matched by a mixer and a throttle valve group to ensure that the thermal parameters of the system refrigerant circulation loop can still match the heat source under partial load conditions, thereby ensuring the reliability and efficiency of the refrigeration system.

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