Refrigerant for replacing R22 as well as preparation method and application of refrigerant

Abstract

The invention belongs to the technical field of refrigerants, and particularly relates to a refrigerant replacing R22 and a preparation method and application of the refrigerant. The refrigerant capable of replacing R22 comprises the following components in parts by weight: 75 to 95 parts of monochlorodifluoromethane, 5 to 15 parts of 1, 1, 1, 2, 3, 3, 3-heptafluoropropane and 1 to 10 parts of isobutane. As a refrigerant for replacing R22, on the whole, the slippage temperature of the refrigerant is extremely low, the filling amount of a system can be obviously reduced, and the refrigerant can be directly filled for replacing the R22.

Description

Technical Field

[0001] This invention belongs to the field of refrigerant technology, specifically relating to a refrigerant that can replace R22, its preparation method, and its application. Background Technology

[0002] R22 (difluorochloromethane), a once widely used refrigerant, has a non-zero ozone depletion potential (ODP=0.04). Although its global warming potential (GWP≈1960) is not extremely high, finding an environmentally friendly alternative remains urgent. Difluoromethane (R32) alone has a lower GWP (approximately 771) and higher volumetric cooling capacity, but its operating pressure is higher than R22, its exhaust temperature is higher, and it is slightly flammable (A2L safety class), posing safety and system compatibility issues for direct replacement. Pentafluoroethane (R125) alone is non-flammable (A1 safety class), but its GWP is extremely high (approximately 3740), and its cooling efficiency is poor, making it less than ideal for environmental protection. 1,1,1,2,3,3,3-heptafluoropropane (R227ea) is non-flammable when used alone (A1 safety class), but its GWP is very high (about 3600), and its thermophysical properties (such as pressure and refrigeration capacity) are very different from those of R22, so it cannot be directly replaced.

[0003] Several alternatives to R22 exist in existing technologies, such as mixed refrigerants like R407C and R410A. However, R407C has a large temperature glide, affecting its performance in systems with large load fluctuations or high condensing temperatures (such as small cold storage facilities and water-cooled air conditioners). R410A operates at much higher pressures than R22, requiring replacement of the entire system, which is costly, and its energy efficiency degradation at high condensing temperatures is also a concern. Especially in applications such as refrigeration and district cooling, systems frequently face condensing temperatures as high as 45°C or even higher, placing higher demands on the thermal stability of the refrigerant and the system's pressure resistance. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a refrigerant to replace R22, its preparation method, and its applications. As a refrigerant to replace R22, the refrigerant of this invention generally exhibits an extremely low glide temperature, can significantly reduce the system charge amount, and can be directly used to replace R22 refrigerant.

[0005] The technical solution provided by this invention is as follows: A refrigerant to replace R22 comprises the following components in parts by weight: 75-95 parts of difluorochloromethane (R22, CHClF2), 5-15 parts of 1,1,1,2,3,3,3-heptafluoropropane (R227ea, CF3CHFCF3), and 1-10 parts of isobutane (R600a, C4H... 10 ).

[0006] Based on the above technical solutions, the refrigerant that replaces R22 has the advantages of reducing the GWP value, significantly reducing the system charge amount, and allowing for direct charging of refrigerant that can replace R22.

[0007] This invention significantly improves safety by adding R227ea to suppress flammability.

[0008] Preferably, the refrigerant that replaces R22 comprises the following components in parts by weight: 75-85 parts of difluorochloromethane, 5-10 parts of 1,1,1,2,3,3,3-heptafluoropropane, and 1-5 parts of isobutane.

[0009] Preferably, the refrigerant that replaces R22 comprises the following components in parts by weight: 75-85 parts of difluorochloromethane, 11-15 parts of 1,1,1,2,3,3,3-heptafluoropropane, and 6-10 parts of isobutane.

[0010] Preferably, the refrigerant that replaces R22 comprises the following components in parts by weight: 86-95 parts of difluorochloromethane, 5-10 parts of 1,1,1,2,3,3,3-heptafluoropropane, and 1-5 parts of isobutane.

[0011] Preferably, the refrigerant that replaces R22 comprises the following components in parts by weight: 86-95 parts of difluorochloromethane, 11-15 parts of 1,1,1,2,3,3,3-heptafluoropropane, and 6-10 parts of isobutane.

[0012] More preferably, the refrigerant that replaces R22 comprises the following components in parts by weight: 76 parts of difluorochloromethane, 6 parts of 1,1,1,2,3,3,3-heptafluoropropane, and 2 parts of isobutane.

[0013] More preferably, the refrigerant that replaces R22 comprises the following components in parts by weight: 85 parts of difluorochloromethane, 10 parts of 1,1,1,2,3,3,3-heptafluoropropane, and 5 parts of isobutane.

[0014] More preferably, the refrigerant that replaces R22 comprises the following components in parts by weight: 94 parts of difluorochloromethane, 14 parts of 1,1,1,2,3,3,3-heptafluoropropane, and 9 parts of isobutane.

[0015] Specifically: The refrigerant that can replace R22 is any combination of the following proportions: The proportions of difluorochloromethane are 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, and 95. The parts of 1,1,1,2,3,3,3-heptafluoropropane are 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, and 15. The isobutane fractions are 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10.

[0016] The present invention also provides a method for preparing the above-mentioned refrigerant to replace R22, comprising the following steps: injecting each component into a pressure-resistant container at room temperature according to the weight ratio, mixing them evenly in the liquid phase using a physical mixing method, and obtaining the refrigerant after standing.

[0017] The present invention also provides applications of the above-mentioned refrigerants that replace R22, for replacing R22 refrigerant in air-cooled systems; or for replacing R22 refrigerant in water-cooled systems; or for replacing R22 working fluid in heat pumps.

[0018] The beneficial effects of this invention are as follows: 1) The refrigerant of this invention has an extremely low glide temperature; 2) Compared to R22, the refrigerant of the present invention has a higher latent heat of vaporization; 3) Compared to R22, the refrigerant of the present invention has a lower COP and GWP value; 4) It can be directly charged to replace R22 refrigerant, significantly reducing the system charge amount and making replacement convenient. Detailed Implementation

[0019] The principles and features of the present invention are described below. The embodiments given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0020] Unless otherwise specified, the test methods used in the embodiments are conventional methods; unless otherwise specified, the materials and reagents used are commercially available.

[0021] Example 1 A refrigerant to replace R22 comprises the following components in parts by weight: 94 parts of difluorochloromethane, 5 parts of 1,1,1,2,3,3,3-heptafluoropropane, and 1 part of isobutane.

[0022] The preparation method of refrigerant is as follows: Based on weight percentage, 94% R22, 5% R227ea, and 1% R600a are taken and physically mixed at room temperature to be used as refrigerant.

[0023] Example 2 A refrigerant to replace R22 comprises the following components in parts by weight: 81 parts of difluorochloromethane, 12 parts of 1,1,1,2,3,3,3-heptafluoropropane, and 7 parts of isobutane.

[0024] The preparation method of refrigerant is as follows: Based on weight percentage, 81% R22, 12% R152a, and 7% R600a are taken and physically mixed at room temperature to be used as refrigerant.

[0025] Example 3 A refrigerant to replace R22 comprises the following components in parts by weight: 88 parts of difluorochloromethane, 8 parts of 1,1,1,2,3,3,3-heptafluoropropane, and 4 parts of isobutane.

[0026] The preparation method of refrigerant is as follows: Based on weight percentage, 88% R22, 8% R227ea, and 4% R600a are taken and physically mixed at room temperature to be used as refrigerant.

[0027] Example 4 A refrigerant to replace R22 comprises the following components in parts by weight: 79 parts of difluorochloromethane, 13 parts of 1,1,1,2,3,3,3-heptafluoropropane, and 8 parts of isobutane.

[0028] The preparation method of refrigerant is as follows: Based on weight percentage, 79% R22, 13% R227ea, and 8% R600a are taken and physically mixed at room temperature to be used as refrigerant.

[0029] Example 5 A refrigerant to replace R22 comprises the following components in parts by weight: 75 parts of difluorochloromethane, 15 parts of 1,1,1,2,3,3,3-heptafluoropropane, and 10 parts of isobutane.

[0030] The preparation method of refrigerant is as follows: Based on weight percentage, 75% R22, 15% R227ea, and 10% R600a are taken and physically mixed at room temperature to be used as refrigerant.

[0031] Example 6 A refrigerant to replace R22 comprises the following components in parts by weight: 85 parts of difluorochloromethane, 10 parts of 1,1,1,2,3,3,3-heptafluoropropane, and 5 parts of isobutane.

[0032] The preparation method of refrigerant is as follows: Based on weight percentage, 85% R22, 10% R227ea, and 5% R600a are taken and physically mixed at room temperature to be used as refrigerant.

[0033] Example 7 A refrigerant to replace R22 comprises the following components in parts by weight: 77 parts of difluorochloromethane, 14 parts of 1,1,1,2,3,3,3-heptafluoropropane, and 9 parts of isobutane.

[0034] The preparation method of refrigerant is as follows: Based on weight percentage, 77% R22, 14% R227ea, and 9% R600a are taken and physically mixed at room temperature to be used as refrigerant.

[0035] The infusion volumes for the seven embodiments described above are shown in Table 1: Table 1 Comparison of relative R22 infusion volume in Examples 1-7:

[0036] The selected design condition is: medium temperature condition. The unit type is suitable for temperate air conditioning of T1 climate type (GB / T7725-2004), and the following values ​​are taken: evaporation temperature = 7.2℃, subcooling = 5℃, condensation temperature = 54.4℃, superheat = 7℃. The compressor isentropic efficiency is 0.8 in the calculation.

[0037] According to the requirements of the national standard GB / T 7725-2022 "Room Air Conditioners", the following data were experimentally measured on the Gree split wall-mounted room air conditioner: KFR-32GW / (32583)FNAa-A3, and the performance parameters were compared: coefficient of performance (COP), relative coefficient of performance (COP), volumetric cooling capacity (Qv), relative unit volumetric cooling capacity (Qv), condensing pressure, GWP, latent heat of vaporization, temperature glide, and lower flammability limit, as shown in Table 2.

[0038] Table 2 Comparison of performance parameters of 7 embodiments of the present invention with R22.

[0039] As can be seen from the data in the table above, compared with R22, the present invention has the following advantages in performance: 1) By comparing the refrigerant charge amount, it was found that the charge amount of the new refrigerant is lower than that of R22, which can reduce the amount of refrigerant used in the system and improve the safety of the system to a certain extent.

[0040] 2) By comparing the performance parameters, it was found that the volumetric cooling capacity Qv and coefficient of performance COP of the new refrigerant are close to those of the system using R22, indicating that the new refrigerant is feasible to replace R22 from a performance perspective; in terms of latent heat of vaporization, the new refrigerant is higher than R22 in all aspects, indicating that the new refrigerant can transport heat more efficiently during the cycle.

[0041] 3) The experimental results also show that the condensing pressure of the new refrigerant is not much different from that of R22, which proves the feasibility of using the direct injection replacement scheme.

[0042] Based on the above-mentioned performance advantages, this invention has the following advantages when replacing R22: 1) Replacing with a new refrigerant can increase the latent heat of vaporization; 2) The system perfusion volume has decreased significantly; 3) It can be directly filled with a replacement for R22 refrigerant, making replacement convenient.

[0043] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A refrigerant to replace R22, characterized in that, It includes the following components in parts by weight: 75-95 parts of difluorochloromethane, 5-15 parts of 1,1,1,2,3,3,3-heptafluoropropane, and 1-10 parts of isobutane.

2. The refrigerant to replace R22 according to claim 1, characterized in that, It includes the following components in parts by weight: 75-85 parts of difluorochloromethane, 5-10 parts of 1,1,1,2,3,3,3-heptafluoropropane, and 1-5 parts of isobutane.

3. The refrigerant to replace R22 according to claim 1, characterized in that, It includes the following components in parts by weight: 75-85 parts of difluorochloromethane, 11-15 parts of 1,1,1,2,3,3,3-heptafluoropropane, and 6-10 parts of isobutane.

4. The refrigerant to replace R22 according to claim 1, characterized in that, It includes the following components in parts by weight: 86-95 parts of difluorochloromethane, 5-10 parts of 1,1,1,2,3,3,3-heptafluoropropane, and 1-5 parts of isobutane.

5. The refrigerant to replace R22 according to claim 1, characterized in that, It includes the following components in parts by weight: 86-95 parts of difluorochloromethane, 11-15 parts of 1,1,1,2,3,3,3-heptafluoropropane, and 6-10 parts of isobutane.

6. The refrigerant to replace R22 according to claim 1, characterized in that, It comprises the following components in parts by weight: 76 parts of difluorochloromethane, 6 parts of 1,1,1,2,3,3,3-heptafluoropropane, and 2 parts of isobutane.

7. The refrigerant to replace R22 according to claim 1, characterized in that, It comprises the following components in parts by weight: 85 parts of difluorochloromethane, 10 parts of 1,1,1,2,3,3,3-heptafluoropropane, and 5 parts of isobutane.

8. The refrigerant to replace R22 according to claim 1, characterized in that, It comprises the following components in parts by weight: 94 parts of difluorochloromethane, 14 parts of 1,1,1,2,3,3,3-heptafluoropropane, and 9 parts of isobutane.

9. A method for preparing a refrigerant to replace R22 according to any one of claims 1 to 8, characterized in that, Includes the following steps: According to the stated weight ratio, each component is injected into a pressure-resistant container at room temperature, and then mixed evenly in the liquid phase using a physical mixing method. After standing, the refrigerant can be obtained.

10. An application of a refrigerant that replaces R22 according to any one of claims 1 to 8, characterized in that: Used to replace R22 refrigerant in air-cooled systems; Alternatively, it can be used to replace R22 refrigerant in water-cooling systems; Alternatively, it can be used to replace the R22 working fluid in heat pumps.

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