Compositions containing difluoromethane and fluorine substituted olefins
Compositions comprising multi-fluorinated olefins and HFC-32 are disclosed. Such compositions are useful particularly for in stationary refrigeration and air conditioning equipment.
1. A method of transferring heat to or from a fluid or body in an air conditioning system that has been designed for use with or has been used with the refrigerant R-410A and has a condenser and an evaporator, said method comprising:
providing a heat transfer composition in the air conditioning system, said heat transfer composition comprising a refrigerant consisting of:
(a) difluoromethane (R-32) in an amount from about 68.6 weight percent to about 75.6 weight percent; and
(b) 1,1,1,2-tetrafluoropropene (HFO-1234yf) in an amount from about 24.4 weight percent to about 31.4 weight percent; and
causing a phase change in said refrigerant and exchanging heat with said fluid or body during said phase change, wherein said refrigerant has an evaporator glide and a condenser glide of less than about 2° C.
2. The method of claim 1 wherein said air conditioning system is selected from the group consisting of stationary air conditioning systems, chillers, heat pump systems, and combinations of two or more of these.
3. The method of claim 1 wherein difluoromethane (R-32) is present in said refrigerant an amount of from 68.6 weight percent to 75.6 weight percent and said HFO-1234yf is present in said refrigerant in an amount of from 24.4 weight percent to 31.4 weight percent.
4. The method of claim 1 wherein said refrigerant consists of about 30% by weight of said difluoromethane (R-32) and about 70% by weight of said HFO-1234yf.
5. The method of claim 1 wherein said refrigerant has a GWP of less than 400.
6. The method of claim 1 wherein said refrigerant consists of about 68.6% by weight of said difluoromethane (R-32) and about 31.4% by weight of said HFO-1234yf.
7. A method of providing cooling in an air conditioning system of the type comprising a compressor, a condenser, an evaporator and a heat transfer composition in the system, the method comprising:
a. circulating said heat transfer composition in the system, wherein said heat transfer composition comprises a refrigerant consisting essentially of:
(i) difluoromethane (R-32) in an amount from about 68.6 weight percent to about 75.6 weight percent; and
(ii) 1,1,1,2-tetrafluoropropene (HFO-1234yf) in an amount from about 24.4 weight percent to about 31.4 weight percent; and;
b. providing cooling by evaporating said refrigerant in said evaporator, wherein said system operates with a system capacity of at least 92% relative to that of R-410A in said air conditioning system and wherein the system operates with an evaporator glide of 2° C. or less.
8. The method of claim 7 wherein said composition has a capacity of about 100% of R-410A in said air conditioning system.
9. The method of claim 7 wherein difluoromethane (R-32) is present in said refrigerant an amount of from 68.6 weight percent to 75.6 weight percent and said HFO-1234yf is present in said refrigerant in an amount of from 24.4 weight percent to 31.4 weight percent.
10. The method of claim 9 herein said refrigerant consists of about 30% by weight of said difluoromethane (R-32) and about 70% by weight of said HFO-1234yf.
11. The method of claim 7 wherein said system operates with a condenser glide of 2° C. or less.
12. The method of claim 7 wherein said refrigerant consists of about 68.6% by weight of said difluoromethane (R-32) and about 31.4% by weight of said HFO-1234yf.
13. An air conditioning system of the type comprising a compressor, a condenser, an evaporator and a heat transfer composition in the system, the improvement comprising said heat transfer composition comprising a refrigerant consisting essentially of:
(i) difluoromethane (R-32) in an amount from about 68.6 weight percent to about 75.6 weight percent; and
(ii) 1,1,1,2-tetrafluoropropene (HFO-1234yf) in an amount from about 24.4 weight percent to about 31.4 weight percent, wherein in operation said system operates with a capacity of at least 92% relative to that of R-410A in said air conditioning system and wherein the system operates with an evaporator glide of 2° C. or less.
14. The air conditioning system of claim 13 wherein said difluoromethane (R-32) is present in said refrigerant an amount of from 68.6 weight percent to 75.6 weight percent and said HFO-1234yf is present in said refrigerant in an amount of from 24.4 weight percent to 31.4 weight percent.
15. The air conditioning system of claim 14 wherein said refrigerant has a GWP of less than 400.
16. The air conditioning system of claim 13 wherein said system operates with a condenser glide of 2° C. or less.
17. The air conditioning system of claim 13 wherein said refrigerant has a capacity of about 100% of R-410A in said air conditioning system.
18. The air conditioning system of claim 14 herein said refrigerant consists of about 30% by weight of said difluoromethane (R-32) and about 70% by weight of said HFO-1234yf.
19. The method of claim 13 wherein said refrigerant consists of about 68.6% by weight of said difluoromethane (R-32) and about 31.4% by weight of said HFO-1234yf.