Liquid carbon dioxide refrigeration system

Abstract

A liquid carbon dioxide refrigeration system is provided. The refrigeration system may include a storage tank arranged for storing liquid carbon dioxide, and a vessel arranged to separate carbon dioxide into a vapor carbon dioxide portion and a liquid carbon dioxide portion. A first conduit is coupled to the storage tank and the first vessel such that liquid carbon dioxide can pass from the storage tank to the first vessel. A second conduit is coupled to the first vessel such that the liquid carbon dioxide portion can pass into a refrigeration device, and a third conduit is coupled to the first vessel and the first conduit to recycle the vapor carbon dioxide portion back to the first conduit. The third conduit may include a refrigeration package to compress and liquefy the vapor carbon dioxide portion

1 . A method of delivering liquid carbon dioxide to a refrigeration device, the method comprising:
 releasing carbon dioxide from a storage tank into a fluid conduit and toward a refrigeration device;   separating the carbon dioxide into a vapor carbon dioxide portion and a liquid carbon dioxide portion;   recycling the vapor carbon dioxide portion into the fluid conduit; and   introducing the liquid carbon dioxide portion near its triple point into the refrigeration device.   
     
     
         2 . The method of  claim 1 , wherein the act of recycling the vapor carbon dioxide portion into the fluid conduit includes a refrigerating package for the vapor carbon dioxide portion. 
     
     
         3 . The method of  claim 1 , wherein the act of separating the carbon dioxide includes reducing the pressure of the carbon dioxide. 
     
     
         4 . The method of  claim 3 , wherein the act of separating the carbon dioxide includes introducing the carbon dioxide into a first vessel, and wherein the pressure of the first vessel is maintained below the pressure of the introduced carbon dioxide. 
     
     
         5 . The method of  claim 3 , wherein the act of separating the carbon dioxide includes introducing the carbon dioxide into a first vessel, and wherein the pressure of the carbon dioxide is reduced after the carbon dioxide is introduced into the first vessel. 
     
     
         6 . The method of  claim 1 , wherein the carbon dioxide is released into a primary fluid conduit extending between the storage tank and the refrigeration device, and the act of separating the carbon dioxide includes transferring the carbon dioxide into a secondary flow circuit for additional conditioning. 
     
     
         7 . The method of  claim 1 , wherein the act of introducing the liquid carbon dioxide portion into the refrigeration device includes pumping the liquid carbon dioxide portion into the refrigeration device. 
     
     
         8 . The method of  claim 1 , wherein the act of separating the carbon dioxide includes introducing a first portion of the carbon dioxide into a first vessel and introducing a second portion of the carbon dioxide into two or more vessels. 
     
     
         9 . A liquid carbon dioxide refrigeration system secondary flow circuit configured to be coupled to a primary fluid conduit extending between a carbon dioxide storage tank and a refrigeration device configured to receive carbon dioxide from the storage tank, the secondary flow circuit comprising:
 a first vessel constructed and arranged to separate carbon dioxide into a vapor carbon dioxide portion and a liquid carbon dioxide portion;   a downstream conduit coupled to the first vessel and constructed and arranged such that the liquid carbon dioxide portion can pass either into the refrigeration system or into the primary fluid conduit;   a recycle conduit coupled to the first vessel, the recycle conduit constructed and arranged to recycle the vapor carbon dioxide portion back to the primary fluid conduit; and   wherein the recycle conduit comprises a refrigeration package configured to compress and liquefy vapor carbon dioxide portion.   
     
     
         10 . The liquid carbon dioxide refrigeration system secondary flow circuit of  claim 9 , further comprising:
 a second vessel constructed and arranged to separate the carbon dioxide into a vapor carbon dioxide portion and a liquid carbon dioxide portion, wherein the secondary flow circuit is configured to cycle between separating carbon dioxide in the first vessel and two or more vessels.   
     
     
         11 . The liquid carbon dioxide refrigeration system secondary flow circuit of  claim 9 , further comprising a pressure reducing element positioned upstream of the first vessel and configured to lower the pressure of the carbon dioxide. 
     
     
         12 . The liquid carbon dioxide refrigeration system secondary flow circuit of  claim 9 , wherein the downstream conduit comprises a pump. 
     
     
         13 . A liquid carbon dioxide refrigeration system comprising:
 a storage tank constructed and arranged for storing liquid carbon dioxide;   a primary fluid conduit having a first end coupled to the storage tank and a second end configured to be coupled to a refrigeration device, wherein the primary fluid conduit is configured to allow carbon dioxide to pass from the storage tank and into the refrigeration device;   a secondary flow circuit coupled to the primary fluid conduit, the secondary flow circuit comprising:
 a first vessel constructed and arranged to separate carbon dioxide into a vapor carbon dioxide portion and a liquid carbon dioxide portion; 
 a secondary conduit coupled to the primary fluid conduit and the first vessel, the secondary fluid conduit constructed and arranged such that the carbon dioxide can pass from the primary fluid conduit and into the first vessel; 
 a downstream conduit coupled to the first vessel and constructed and arranged such that the liquid carbon dioxide portion can pass either into the refrigeration system or into the primary fluid conduit; and 
 a recycle conduit coupled to the first vessel and the primary fluid conduit, the recycle conduit constructed and arranged to recycle the vapor carbon dioxide portion back to the primary fluid conduit. 
   
     
     
         14 . The liquid carbon dioxide refrigeration system of  claim 13 , wherein the recycle conduit comprises a refrigeration package configured to compress and liquefy the carbon dioxide vapor portion. 
     
     
         15 . The liquid carbon dioxide refrigeration system of  claim 13  wherein the secondary fluid conduit is coupled to the primary fluid conduit at a first location on the primary fluid conduit and the recycle conduit is coupled to the primary fluid conduit at a second location on the primary fluid conduit, wherein the second location is upstream of the first location. 
     
     
         16 . The liquid carbon dioxide refrigeration system of  claim 13 , wherein the secondary flow circuit further comprises a second vessel constructed and arranged to separate the carbon dioxide into a vapor carbon dioxide portion and a liquid carbon dioxide portion, and wherein the secondary flow circuit is configured to cycle between separating carbon dioxide in the first vessel and in the second vessel. 
     
     
         17 . The liquid carbon dioxide refrigeration system of  claim 16 , wherein the secondary flow circuit further comprises a conduit coupling the first vessel to the second vessel and configured to adjust the pressure between the first vessel and the second vessel.