Patent ID: 7401473
Filing Date: 2008-07-22
Classification: F25B,F25C

Abstract:
1. A dual refrigerant refrigeration system comprising: at least one compressor for compressing a primary refrigerant, as a primary refrigerant vapor, said compressor being engageable in a refrigeration cycle; a refrigerant condenser operatively connected to said at least one compressor for condensing, after said compressing, said primary refrigerant vapor into a primary refrigerant liquid; a spray primary evaporator operatively connected to said at least one compressor and having at least one secondary refrigerant tube through which a secondary refrigerant circulates in said primary evaporator and at least one perforated tube operatively connected to said refrigerant condenser and through which said primary refrigerant liquid flows, said primary refrigerant liquid being sprayed through perforations in said perforated tube onto said at least one secondary refrigerant tube and absorbing thereby a secondary latent heat of said secondary refrigerant and cooling said secondary refrigerant therein to a partially frozen state in which a fusion portion thereof is frozen, said secondary latent heat comprising a latent heat of fusion absorbed during freezing of said fusion portion and said primary refrigerant liquid refrigerant being evaporated into said primary refrigerant vapor by absorbing said secondary latent heat; and at least one secondary evaporator operatively connected to said primary evaporator and engageable in said refrigeration cycle for receiving said partially frozen secondary refrigerant for at least partial thawing of said partially frozen secondary refrigerant, including said fusion portion thereof, into a partially thawed state by at least partial re-absorption of said secondary latent heat, and thereby of said latent heat of fusion, from material refrigerated by said secondary evaporator, said fusion portion increasing said secondary latent heat re-absorbed from said material by said secondary refrigerant during said refrigeration cycle.