Cross-flow spiral heat transfer apparatus with solid belt

Abstract

A heat transfer apparatus for a product includes a housing having an internal chamber; a solid conveyor belt disposed within the internal chamber and arranged in a spiral configuration having upper and lower portions, the spiral configuration including an upper pathway within the upper portion, a lower pathway within the lower portion; a gas flow having an upper gas flow across the upper pathway, a lower gas flow across the lower pathway and in counter-flow to the upper gas flow, wherein the upper gas flow and the lower gas flow define a circulation loop; and a gas circulation device to induce the upper and lower gas flows along the circulation loop.

1 . A heat transfer apparatus for a product, comprising:
 a housing having an internal chamber;   a solid conveyor belt disposed within the internal chamber and arranged in a spiral configuration having upper and lower portions, the spiral configuration, comprising:
 an upper pathway within the upper portion, 
 a lower pathway within the lower portion; 
   a gas flow, comprising:
 an upper gas flow across the upper pathway, 
 a lower gas flow across the lower pathway and in counter-flow to the upper gas flow, wherein the upper gas flow and the lower gas flow define a circulation loop; and 
   a gas circulation device to induce the upper and lower gas flows along the circulation loop.   
     
     
         2 . The apparatus of  claim 1 , wherein the upper gas flow and the lower gas flow are of substantially uniform velocity. 
     
     
         3 . The apparatus of  claim 1 , wherein the upper portion and the upper pathway have a similar width, and the lower portion and the lower pathway have a similar width. 
     
     
         4 . The apparatus of  claim 1 , wherein the gas circulation device comprises at least one fan disposed in at least one of the upper and lower portions. 
     
     
         5 . The apparatus of  claim 1 , further comprising a drum disposed in the internal chamber and extending between the upper and lower portions, and about which is arranged the solid conveyor belt in the spiral configuration. 
     
     
         6 . The apparatus of  claim 5 , wherein the drum comprises an outer sidewall adjacent the solid conveyor belt and impervious to the upper and lower gas flows. 
     
     
         7 . The apparatus of  claim 1 , wherein the upper and lower gas flows comprise gas selected to reduce a temperature of the product. 
     
     
         8 . The apparatus of  claim 7 , wherein the gas comprises a cryogenic gas selected from the group consisting of carbon dioxide, nitrogen and combinations thereof. 
     
     
         9 . The apparatus of  claim 1 , wherein the upper and lower gas flows comprise a gas selected to heat the product. 
     
     
         10 . The apparatus of  claim 1 , wherein the circulation loop is arranged in the internal chamber. 
     
     
         11 . The apparatus of  claim 1 , wherein the product comprises a food product.