CN-121991638-A - Substitute refrigerant of HCFC-22, preparation method and application thereof

Abstract

The invention belongs to the technical field of refrigerants, and particularly relates to a substitute refrigerant of HCFC-22, a preparation method and application thereof. The substitute refrigerant comprises, by weight, 60-70 parts of difluoromethane, 10-20 parts of ‌ pentafluoroethane ‌ and 15-25 parts of 1,2, 3-heptafluoropropane. The refrigerant ODP is zero, and the GWP is equal to or lower than R22, and is especially designed for severe working conditions of a water-cooled refrigeration system, a refrigeration storage unit and the like running at high condensation temperature. Compared with R22, the unit volume refrigerating capacity of the system is obviously improved, and the system has excellent thermal stability and system reliability on the premise that the working pressure is obviously lower than that of R22, so that the system is an ideal choice for replacing the existing R22 system, especially the high-pressure difference and high-load application scenes such as refrigeration, medium-sized central air conditioner and the like.

Inventors

• WANG ZHIGUO
• LIU JINGJING
• LIU YE
• ZHANG LI

Assignees

• 湖北瑞能华辉能源管理有限公司
• 西安交通大学

Dates

Publication Date

20260508

Application Date

20251216

Claims (10)

1. 1. A substitute refrigerant of HCFC-22 is characterized by comprising the following components, by weight, 60-70 parts of difluoromethane, 10-20 parts of ‌ pentafluoroethane ‌ and 15-25 parts of 1,2, 3-heptafluoropropane.
2. 2. The replacement refrigerant of HCFC-22 as claimed in claim 1, comprising the components of 65 to 70 parts by weight of difluoromethane, 15 to 20 parts by weight of ‌ pentafluoroethane ‌,20 to 25 parts by weight of 1,2, 3-heptafluoropropane.
3. 3. The replacement refrigerant of HCFC-22 as claimed in claim 1, comprising 65 to 70 parts by weight of difluoromethane, 10 to 14 parts by weight of ‌ pentafluoroethane ‌,15 to 19 parts by weight of 1,2, 3-heptafluoropropane.
4. 4. The replacement refrigerant of HCFC-22 as claimed in claim 1, comprising the components of 60 to 64 parts by weight of difluoromethane, 15 to 20 parts by weight of ‌ pentafluoroethane ‌,20 to 25 parts by weight of 1,2, 3-heptafluoropropane.
5. 5. The replacement refrigerant of HCFC-22 as claimed in claim 1, comprising the components of 60 to 64 parts by weight of difluoromethane, 10 to 14 parts by weight of ‌ pentafluoroethane ‌,15 to 19 parts by weight of 1,2, 3-heptafluoropropane.
6. 6. The replacement refrigerant of HCFC-22 as in claim 1, comprising the components of, by weight, 70 parts difluoromethane, 15 parts ‌ parts pentafluoroethane ‌,15 parts 1,2, 3-heptafluoropropane.
7. 7. The replacement refrigerant of HCFC-22 as in claim 1, comprising the components of 65 parts by weight of difluoromethane, 15 parts by weight of pentafluoroethane ‌,20 parts by weight of 1,2, 3-heptafluoropropane.
8. 8. The replacement refrigerant of HCFC-22, according to claim 1, comprising the components of 60 parts by weight of difluoromethane, 20 parts by weight of pentafluoroethane ‌,20 parts by weight of 1,2, 3-heptafluoropropane.
9. 9. A process for the preparation of an alternative refrigerant to HCFC-22 as claimed in any one of claims 1 to 8, comprising the steps of: S1, preparing raw materials, namely preparing high-purity difluoromethane, pentafluoroethane and 1,2, 3-heptafluoropropane, wherein the purity of each raw material is not lower than 99.9%; S2, preprocessing equipment, namely taking a clean and dry pressure-resistant steel cylinder, and vacuumizing the steel cylinder until the vacuum degree is below 50 Pa so as to thoroughly remove air and moisture in the steel cylinder; S3, filling the components, namely accurately filling liquid 1,2, 3-heptafluoropropane, pentafluoroethane and difluoromethane into a pretreated steel cylinder in sequence according to the weight portion ratio of any one of claims 1 to 8 at the temperature of 20-25 ℃; s4, mixing and homogenizing, namely sealing the filled steel cylinder, placing the steel cylinder on a mixing device capable of horizontally rolling, continuously rolling and mixing for 2-4 hours at the rotating speed of 10-15 rpm, and ensuring that all components are fully and uniformly mixed to form a homogeneous mixed refrigerant; S5, standing and curing, namely standing and storing the mixed steel bottle at room temperature for at least 24 hours to obtain the substitute refrigerant of the HCFC-22.
10. 10. Use of an alternative refrigerant of HCFC-22 as claimed in any one of claims 1 to 8, wherein: for replacing HCFC-22 in refrigeration or heat pump systems operating at condensing temperatures not less than 40 ℃; the refrigerating or heat pump system is positioned in a water-cooled chiller, a refrigeration system of a refrigeration house of-45 ℃ to 15 ℃ or a unit air conditioner with the condensation temperature of 42 ℃ to 47 ℃.

Description

Substitute refrigerant of HCFC-22, preparation method and application thereof Technical Field The invention belongs to the technical field of refrigerants, and particularly relates to a substitute refrigerant of HCFC-22, a preparation method and application thereof. Background HCFC-22 (R22, difluoromethane chloride) is a widely used refrigerant because of its non-zero ozone depletion potential (odp=0.04). Although their global warming potential (gwp≡1960) is not very high, finding an environmentally friendly alternative is still an urgent task. Difluoromethane (R32) alone has lower GWP (about 771) and high refrigeration per unit volume, but its working pressure is higher than R22, exhaust temperature is high, and it has mild flammability (A2L safety class), directly replacing the safety and system compatibility issues. Pentafluoroethane (R125) alone is not flammable (A1 safety class), but its GWP is extremely high (about 3740), refrigeration efficiency is poor, and is not an ideal environmental option. 1,2, 3-heptafluoropropane (R227 ea) alone is not flammable (A1 safety class), but its GWP is very high (about 3600), and its thermophysical properties (e.g., pressure, refrigeration capacity) are very different from R22, and cannot be directly substituted. There are a number of alternatives to R22 in the prior art, such as mixed refrigerants such as R407C, R a. However, R407C has larger temperature slippage, the performance is affected in systems with large load fluctuation or higher condensation temperature (such as small-sized refrigeration houses and water-cooling air conditioners), the working pressure of R410A is far higher than that of R22, the whole system equipment needs to be replaced, the cost is high, and the energy efficiency attenuation problem at high condensation temperature is also worth focusing. Particularly in the application fields of freezing and refrigerating, regional refrigerating and the like, the system is often subjected to a condensation temperature of up to 45 ℃ or even higher, which puts higher demands on the thermal stability of the refrigerant and the pressure bearing capacity of the system. Therefore, it is of great importance to develop an R22 replacement refrigerant with zero ODP, controllable GWP, and particularly capable of maintaining excellent refrigeration capacity and system reliability under severe conditions of high load, high condensing temperature. The invention aims to overcome the defects of the prior art, and provides a novel mixed refrigerant, wherein the ODP is zero, the GWP is equal to or slightly lower than that of R22, the refrigerating capacity per unit volume is obviously higher than that of R22, and meanwhile, the working pressure interval is more suitable for the transformation and substitution of the existing R22 system, and the use safety is ensured. Disclosure of Invention In order to solve the defects in the prior art, the invention provides a novel mixed refrigerant, wherein the ODP is zero, the GWP is equal to or slightly lower than that of R22, the unit volume refrigeration capacity is obviously higher than that of R22, and the thermal physical properties (such as working pressure and critical parameters) of the mixed refrigerant are particularly suitable for modifying the existing R22 system so as to cope with the common high condensing temperature and high load working conditions in the applications of freezing, refrigerating, water-cooling central air conditioning and the like, and ensure the use safety. The invention is suitable for medium-low temperature refrigerating systems, in particular to HCFC-22 low GWP substitution refrigerant of a water-cooled unit running at higher condensing temperature, and a preparation method and application thereof. The technical scheme provided by the invention is as follows: A substitute refrigerant of HCFC-22 comprises, by weight, 60-70 parts of difluoromethane (R32), 10-20 parts of ‌ pentafluoroethane (R125) ‌ and 15-25 parts of 1,2, 3-heptafluoropropane (R227 ea). Based on the technical scheme: Compared with the existing HCFC-22 refrigerant, the refrigerant provided by the invention has the advantages that the ODP is reduced to zero, the refrigerating capacity per unit volume is increased by 24% -37%, and the GWP is equivalent or slightly reduced; compared with single use of difluoromethane, the refrigerant provided by the invention has the advantages that the working pressure and the exhaust temperature are more reasonable, the safety is obviously improved (the combustibility is inhibited by adding R125 and R227 ea); compared with pentafluoroethane used alone, the refrigerant provided by the invention has the advantages that the GWP value is obviously reduced, and the refrigerating efficiency (refrigerating capacity per unit volume) is greatly improved; Compared with the independent use of 1,2, 3-heptafluoropropane, the refrigerant provided by the invention has the advantages of working pressure and refri