Patent Publication Number: US-10316233-B2

Title: Refrigerant compositions

Description:
FIELD 
     The disclosure herein relates to refrigerant compositions, which can be used in, for example, refrigeration, air conditioning, and/or heat pump systems, which, for example, can be incorporated into a heating, ventilation and air conditioning (HVAC) system or unit. 
     BACKGROUND 
     Concern about environment impact, e.g. ozone depletion, and the approval of the Montreal Protocol resulted in a movement to replace ozone depleting refrigerant compositions, such as for example, chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs). As a result, replacement refrigerant compositions, such as for example hydrofluorocarbon (HFC) refrigerants and hydrofluoroolefins (HFOs) refrigerants are commercialized. However, it has been recognized that HFC refrigerants may contribute to environment changes through their relatively large greenhouse effect, e.g. having a relatively large global warming potential (GWP). 
     SUMMARY 
     Refrigerant compositions are described, which can be used for example, in refrigeration, air conditioning, and/or heat pump systems which for example, can be incorporated into a heating, ventilation and air conditioning (HVAC) system or unit. The refrigerant composition includes an amount of a R125 refrigerant, an amount of a R32 refrigerant, and an amount of a R1234yf refrigerant, where the R32 refrigerant has higher flammability than the R125 refrigerant, and the R1234yf refrigerant has higher flammability than the R125 refrigerant. 
    
    
     DETAILED DESCRIPTION 
     Some relatively low GWP HFCs, (e.g. R32, R152a) and ultra-low GWP HFOs (e.g. R1234yf, R1234ze(E)) are mildly flammable, which may prevent the use of these low GWP refrigerants in a building HVAC system. 
     Embodiments as disclosed herein are directed to refrigerant compositions to reduce flammability of a refrigerant or a refrigerant composition, e.g. a refrigerant composition of low GWP HFC R32 and/or an ultra-low GWP HFO R1234yf, by including a non-flammable refrigerant (e.g. R125). In some embodiments, refrigerant compositions including a flammable refrigerant composition such as for example a low GWP HFC R32 and/or an ultra-low GWP HFO R1234yf, and a non-flammable refrigerant R125 are disclosed. The refrigerant compositions may have a lower flammability than the refrigerant composition of R32 and/or R1234yf, a GWP that is lower than R32, and similar performance characteristics as the refrigerant composition of R32 and/or R1234yf. 
     In some embodiments, R125 may be added to a current refrigerant in the HVAC system to reduce the flammability of the HVAC system. In some embodiments, the current refrigerant in the HVAC system may include R32. In some embodiments, the current refrigerant in the HVAC system may be 72.5% wt R32 and 27.5% wt R1234yf, which is marketed as DR-5 by Dupont®, or may be 68.9% wt R32 and 31.1% wt R1234yf, which is marketed as DR-5A by Dupont®. In some embodiments, the current refrigerant can be other suitable refrigerants, some of which can be found in U.S. Pat. No. 7,914,698, which is incorporated herein by reference in its entirety. 
     Exemplary embodiments of refrigerant compositions as disclosed herein are listed in the following Table 1. 
     
       
         
           
               
               
               
               
             
               
                   
                 TABLE 1 
               
               
                   
                   
               
               
                   
                 Composition (% by weight) 
                 GWP 
                 BV 
               
               
                   
                   
               
             
            
               
                   
                 50% R32/50% R125 
                 1924 
                 n/a 
               
               
                   
                 100% R32 
                 ~677 
                 6.7 
               
               
                   
                 R32/R125/R1234yf 
                 ~677 
                 3.4 
               
               
                   
                 (74.0%/5.5%/20.5%) 
                 (e.g. 675) 
               
               
                   
                 R32/R125/R1234yf 
                 ~677 
                 3.1 
               
               
                   
                 (69.0%/6.5%/25.5%) 
                 (e.g. 673) 
               
               
                   
                 R32/R125/R1234yf 
                 ~677 
                 3.0 
               
               
                   
                 (67.0%/7.0%/26.0%) 
               
               
                   
                 R32/R125/R1234yf 
                 ~677 
                 2.8 
               
               
                   
                 (64.0%/7.5%/28.5%) 
                 (e.g. 671) 
               
               
                   
                 R32/R125/R1234yf 
                 ~750 
                 2.6 
               
               
                   
                 (62.0%/10.5%/27.5%) 
                 (e.g. 753) 
               
               
                   
                 R32/R125/R1234yf 
                 ~677 
                 1.3 
               
               
                   
                 (20.0%/17.5%/62.5%) 
                 (e.g. 674) 
               
               
                   
                 R32/R125/R1234yf 
                 ~750 
                 1.1 
               
               
                   
                 (18.0%/20.0%/62.0%) 
                 (e.g. 756) 
               
               
                   
                   
               
            
           
         
       
     
     Table 1 illustrates simulation results of GWP and BV of various refrigerant compositions. As illustrated in Table 1, a refrigerant composition R32/R125 (50% wt/50% wt) has a GWP of 1924 is refrigerant R410A and can be compared to other refrigerant blends for potential replacement. 
     Refrigerant compositions of R32/R125/R1234yf (74.0% wt/5.5% wt/20.5% wt), R32/R125/R1234yf (69.0% wt/6.5% wt/25.5% wt), R32/R125/R1234yf (64.0% wt/7.5% wt/28.5% wt) and R32/R125/R1234yf (20.0% wt/17.5% wt/62.5% wt) may have a similar GWP as 100% wt R32 (e.g. 677), but increasingly lower BV (e.g. lower flammability) respectively compared to 100% wt R32 (e.g. 6.7). The refrigerant composition of R32/R125/R1234yf (62.0% wt/10.5% wt/27.5% wt), and R32/R125/R1234yf (18.0% wt/20.0% wt/62.0% wt) may have a slightly higher GWP (e.g. 750) compared to 100% wt R32, but a lower BV (e.g. at about 1). The refrigerant composition R32/R125/R1234yf (74.0% wt/5.5% wt/20.5% wt) may be used to replace R410A in some applications. More preferred, the refrigerant compositions R32/R125/R1234yf (69.0% wt/6.5% wt/25.5% wt) may be used to replace R410A in some applications because, for example, a capacity of the refrigerant compositions may be similar to R410A. Even more preferred, any one or more of the refrigerant compositions R32/R125/R1234yf (67.0%/7.0%/26.0%) or R32/R125/R1234yf (64.0% wt/7.5% wt/28.5% wt) or R32/R125/R1234yf (62.0% wt/10.5% wt/27.5% wt) may be used to replace R410A in some applications. The refrigerant compositions R32/R125/R1234yf (20.0% wt/17.5% wt/62.5% wt) or R32/R125/R1234yf (18.0% wt/20.0% wt/62.0% wt) may be used to replace R22, R407C or R404A in some applications, because, for example, a capacity of the refrigerant compositions may be similar to R22, R407C or R404A. 
     With regard to the foregoing description, it is to be understood that changes may be made in detail, without departing from the scope of the present invention. It is intended that the specification and depicted embodiments are to be considered exemplary only, with a true scope and spirit of the invention being indicated by the broad meaning of the claims.