HEAT TRANSFER COMPOSITIONS, METHODS, AND SYSTEMS
The present invention relates to a refrigerant composition, including difluoromethane (HFC-32), pentafluoroethane (HFC-125), and trifluoroiodomethane (CF 3 I) for use in a heat exchange system, including air conditioning and refrigeration applications and in particular aspects to the use of such compositions as a replacement of the refrigerant R-410A for heating and cooling applications and to retrofitting heat exchange systems, including systems designed for use with R-410A.
1 . A refrigerant comprising at least about 97% by weight of the following three compounds, with each compound being present in the following relative percentages:
39 to 45% by weight difluoromethane (HFC-32),
1 to 4% by weight pentafluoroethane (HFC-125), and
51 to 57% by weight trifluoroiodomethane (CF3I).
2 . The refrigerant of claim 1 comprising at least about 99.5% by weight of the following three compounds, with each compound being present in the following relative percentages: 39 to 45% by weight difluoromethane (HFC-32),
1 to 4% by weight pentafluoroethane (HFC-125), and
51 to 57% by weight trifluoroiodomethane (CF3I).
3 . The refrigerant of claim 1 consisting of the following three compounds, with each compound being present in the following relative percentages:
39 to 45% by weight difluoromethane (HFC-32),
1 to 4% by weight pentafluoroethane (HFC-125), and
51 to 57% by weight trifluoroiodomethane (CF3I).
4 . The refrigerant of claim 1 comprising at least about 97% by weight of the following three compounds, with each compound being present in the following relative percentages:
about 41 to about 43% by weight difluoromethane (HFC-32),
1 to 4% by weight pentafluoroethane (HFC-125), and
about 53 to about 56% by weight trifluoroiodomethane (CF3I).
5 . The refrigerant of claim 4 comprising at least about 99.5% by weight of the following three compounds, with each compound being present in the following relative percentages:
about 41 to about 43% by weight difluoromethane (HFC-32),
1 to 4% by weight pentafluoroethane (HFC-125), and
about 53 to about 56% by weight trifluoroiodomethane (CF3I).
6 . The refrigerant of claim 1 consisting essentially of the following three compounds, with each compound being present in the following relative percentages:
41%±1% by weight difluoromethane (HFC-32),
3.5%±0.5% by weight pentafluoroethane (HFC-125),
and 55.5%±0.5% by weight trifluoroiodomethane (CF3I).
7 . The refrigerant of claim 6 consisting of the following three compounds, with each compound being present in the following relative percentages:
41%±1% by weight difluoromethane (HFC-32),
3.5%±0.5% by weight pentafluoroethane (HFC-125),
and 55.5%±0.5% by weight trifluoroiodomethane (CF3I).
8 . The refrigerant of claim 6 consisting essentially of the following three compounds, with each compound being present in the following relative percentages:
41% by weight difluoromethane (HFC-32),
3.5% by weight pentafluoroethane (HFC-125),
and 55.5% by weight trifluoroiodomethane (CF3I).
9 . A heat transfer composition comprising a refrigerant as claimed in claim 1 .
10 . The heat transfer composition of claim 9 further comprising an alkylated naphthalene.
11 . The heat transfer composition of claim 10 further comprising BHT in an amount of from about 0.0001% by weight to about 5% by weight of the heat transfer composition.
12 . The heat transfer composition of claim 11 further comprising a lubricant elected from polyol esters (POEs), poly vinyl ethers (PVEs), mineral oil, and alkylbenzenes (ABs).
13 . The heat transfer composition of claim 12 wherein the lubricant is a polyol ester (POE).
14 . The heat transfer composition of claim 12 wherein the lubricant is a PVE.
15 . A method of cooling in a heat transfer system comprising an evaporator, a condenser and a compressor, the process comprising the steps of
i) condensing a refrigerant of claim 1 and
ii) evaporating the refrigerant in the vicinity of body or article to be cooled;
wherein the temperature of the refrigerant in the evaporator is in the range of from about −40° C. to about 10° C.
16 . The method of claim 15 wherein the temperature of the refrigerant in the evaporator is in the range of from about −30° C. to about 5° C.
17 . The method of claim 15 wherein the temperature of the refrigerant in the evaporator is in the range of from about −40° C. to about −10° C.
18 . The method of claim 15 wherein the system is a residential air conditioning system and wherein the temperature of the refrigerant in the evaporator is in the range of from about 0° C. to about 10° C.
19 . The method of claim 15 wherein the system is a chiller system and wherein the temperature of the refrigerant in the evaporator is in the range of from about 0° C. to about 10° C.
20 . The method of claim 15 wherein the system is a low temperature refrigeration system and wherein the temperature of the refrigerant in the evaporator is in the range of from about −40° C. to about −12° C.