Systems and Methods for Liquefaction of a Gas by Hybrid Heat Exchange

Abstract

A liquefaction system for removing heat from a process fluid to condense the process fluid, the liquefaction system including a primary heat exchanger configured to remove heat from the process fluid via heat exchange with one or more refrigerants, a compressor configured to compress the one or more refrigerants, a first secondary heat exchanger configured to remove heat from the one or more refrigerants via heat exchange with ambient air, and a second secondary heat exchanger configured to remove heat from the one or more refrigerants via heat exchange with ambient water.

1 . A liquefaction system for removing heat from a process fluid to condense the process fluid, the liquefaction system comprising:
 a primary heat exchanger configured to remove heat from the process fluid via heat exchange with one or more refrigerants;   a compressor configured to compress the one or more refrigerants;   a first secondary heat exchanger configured to remove heat from the one or more refrigerants via heat exchange with ambient air; and   a second secondary heat exchanger configured to remove heat from the one or more refrigerants via heat exchange with ambient water.   
     
     
         2 . The liquefaction system of  claim 1 , wherein the first secondary heat exchanger and the second secondary heat exchanger are arranged in series. 
     
     
         3 . The liquefaction system of  claim 2 , further comprising:
 a third secondary heat exchanger configured to remove heat from the one or more refrigerants via heat exchange with ambient air; and   a fourth secondary heat exchanger configured to remove heat from the one or more refrigerants via heat exchange with ambient water.   
     
     
         4 . The liquefaction system of  claim 2 , wherein the compressor is located upstream of the first secondary heat exchanger and the second secondary heat exchanger. 
     
     
         5 . The liquefaction system of  claim 1  wherein the first secondary heat exchanger is configured to remove heat from a first portion of the one or more refrigerants and the second secondary heat exchanger is configured to remove heat from a second portion of the one or more refrigerants. 
     
     
         6 . The liquefaction system of  claim 1 , wherein the primary heat exchanger comprises a first fluid passage fluidly connected with the first secondary heat exchanger configured to reject heat to ambient air, and a second fluid passage fluidly connected with the second secondary heat exchanger configured to reject heat to ambient water. 
     
     
         7 . The liquefaction system of  claim 1 , further comprising:
 a first heat exchanger upstream of the primary heat exchanger and configured to remove heat from the process fluid via heat exchange with ambient air; and   a second heat exchanger upstream of the primary heat exchanger and configured to remove heat from the process fluid via heat exchange with the ambient water.   
     
     
         8 . The liquefaction system of  claim 7 , wherein the first heat exchanger and the second heat exchanger are arranged in series. 
     
     
         9 . The liquefaction system of  claim 8 , wherein the first heat exchanger configured to remove heat from the process fluid via heat exchange with ambient air is upstream of the second heat exchanger configured to remove heat from the process fluid via heat exchange with ambient water. 
     
     
         10 . A method for liquefying a process fluid using a refrigerant, the method comprising:
 (a) transferring heat from the process fluid to the refrigerant in a primary heat exchanger;   (b) flowing the refrigerant from the primary heat exchanger;   (c) compressing the refrigerant stream after (b); and   (d) removing heat from the process fluid via a first heat exchanger operable to effect heat exchange with ambient air and a second heat exchanger operable to effect heat exchange with ambient water.   
     
     
         11 . The method of  claim 10 , wherein the first heat exchanger and the second heat exchanger are in series. 
     
     
         12 . The method of  claim 11 , wherein (d) comprises:
 removing heat directly from the process fluid via heat exchange between the process fluid and ambient air with the first heat exchanger; and   removing heat directly from the process fluid via heat exchange between the process fluid and ambient water with the secondary heat exchanger.   
     
     
         13 . The method of  claim 11  further comprising a third heat exchanger that is not in series with the first heat exchanger and the second heat exchanger. 
     
     
         14 . The method of  claim 11 , wherein (d) comprises:
 removing heat indirectly from the process fluid via heat exchange between the refrigerant and ambient air with the first heat exchanger; and   removing heat indirectly from the process fluid via heat exchange between the refrigerant and ambient water with the second heat exchanger.   
     
     
         15 . The method of  claim 14 , further comprising:
 removing heat indirectly from the process fluid via heat exchange between the refrigerant and ambient air with a third heat exchanger; and   removing heat directly from the process fluid via heat exchange between the refrigerant and ambient water with a fourth heat exchanger.   
     
     
         16 . The method of  claim 15 , wherein the third heat exchanger and the fourth heat exchanger are arranged in series. 
     
     
         17 . The method of  claim 16 , wherein the third heat exchanger and the fourth heat exchanger are not in series with the first heat exchanger and the second heat exchanger, and remove heat from a portion of the one or more refrigerants that has a different temperature from that of another portion of the one or more refrigerants from which the first heat exchanger and the second heat exchanger remove heat. 
     
     
         18 . The method of  claim 10 , wherein the first heat exchanger and the second heat exchanger are not operated in series. 
     
     
         19 . The method of  claim 10 , further comprising operating the hybrid cooling system to effect heat exchange with the ambient water and not with the ambient air, operating the hybrid cooling system to effect heat exchange with the ambient water and not with the ambient air, or operating the hybrid cooling system to effect heat exchange with the ambient air and heat exchange with the ambient water. 
     
     
         20 . The method of  claim 10 , further comprising operating the hybrid cooling system to effect heat exchange with the ambient water and heat exchange with the ambient air when the temperature of the ambient air is above the temperature of the ambient water, and operating the hybrid cooling system to effect heat exchange with the ambient air and not with the ambient water when the temperature of the ambient air is not above the temperature of the ambient water and/or when the temperature of the water is below a minimum operating temperature.