US Patent 10308854 Heat-transfer fluids and use thereof in countercurrent heat exchangers

The invention relates to a ternary composition comprising difluoromethane, 1,3,3,3-tetrafluoropropene and a hydrocarbon-derived compound containing at least two fluorine atoms and having a boiling point of between −30 and −20° C., which is selected from 1,1-difluoroethane, 1,1,1,2-tetrafluoroethane and 2,3,3,3-tetrafluoropropene. This composition is particularly suitable for use as a heat-transfer fluid in the presence of countercurrent heat exchangers.