Co2 freezing apparatus

Abstract

A freezer apparatus for a product includes a chamber; a mechanical refrigeration assembly having a portion thereof disposed within the chamber for reducing a temperature of the product; and a cryogen injection assembly disposed within the chamber for reducing the temperature of the product and operatively associated with the mechanical refrigeration assembly to provide power to move a flow of cryogen refrigerant through the mechanical refrigeration assembly.

What is claimed is: 
     
         1 . A freezer apparatus for a product, comprising:
 a chamber;   a mechanical refrigeration assembly having a portion thereof disposed within the chamber for reducing a temperature of the product; and   a cryogen injection assembly disposed within the chamber for reducing the temperature of the product and operatively associated with the mechanical refrigeration assembly to provide power to move a flow of cryogen refrigerant through the mechanical refrigeration assembly.   
     
     
         2 . The freezer apparatus of  claim 1 , wherein the mechanical refrigeration assembly comprises a closed-loop mechanical refrigeration assembly. 
     
     
         3 . The freezer apparatus of  claim 1 , further comprising a storage tank for the cryogen refrigerant in fluid communication with the mechanical refrigeration assembly. 
     
     
         4 . The freezer apparatus of  claim 1 , further comprising a conveyor for transporting the product through the chamber. 
     
     
         5 . The freezer apparatus of  claim 1 , further comprising a housing in which the chamber is disposed, and an inlet and an outlet in communication with the chamber. 
     
     
         6 . The freezer apparatus of  claim 1 , wherein the cryogen refrigerant comprises carbon dioxide. 
     
     
         7 . The freezer apparatus of  claim 1 , wherein the cryogen injection assembly comprises a circulation device having a passageway for dispensing the cryogen refrigerant into the chamber. 
     
     
         8 . The freezer apparatus of  claim 7 , wherein the circulation device comprises at least one fan. 
     
     
         9 . The freezer apparatus of  claim 7 , wherein the mechanical refrigeration assembly comprises a compressor connected to the circulation device for being powered by the circulation device. 
     
     
         10 . The freezer apparatus of  claim 7 , further comprising at least one nozzle at an end of the passageway for dispensing the cryogen refrigerant as a combination of cryogen gas and cryogen snow into the chamber. 
     
     
         11 . The freezer apparatus of  claim 9 , wherein the chamber comprises a plurality of zones, and the cryogen injection assembly is disposed in a first zone of said plurality of zones. 
     
     
         12 . The freezer apparatus of  claim 11 , wherein the portion of the mechanical refrigeration assembly comprises a heat exchanger disposed in a second zone of said plurality of zones and being in fluid communication with the cryogen injection assembly, and an evaporator disposed in a third zone of said plurality of zones and being in fluid communication with the compressor. 
     
     
         13 . The freezer apparatus of  claim 11 , further comprising a plurality of baffles disposed in the chamber to divide said chamber into said plurality of zones. 
     
     
         14 . The freezer apparatus  claim 12 , further comprising an exhaust for the second zone through which gas is removed from said chamber. 
     
     
         15 . The freezer apparatus of  claim 1 , wherein the product is a food product.