Refrigeration system with high speed rotary pressure exchanger

Abstract

A refrigeration system includes a pressure exchanger (PX). The PX is a rotary liquid piston compressor. The PX includes: a first PX inlet fluidly coupled to a heat exchanger outlet of a heat exchanger comprising a gas cooler or condenser; a first PX outlet fluidly coupled to a heat exchanger inlet of the heat exchanger; a second PX inlet fluidly coupled to an evaporator outlet of an evaporator; and a second PX outlet fluidly coupled to an evaporator inlet of the evaporator.

What is claimed is: 
     
         1 . A refrigeration system comprising:
 a pressure exchanger (PX), wherein the PX is a rotary liquid piston compressor (LPC), wherein the PX comprises:
 a first PX inlet fluidly coupled to a heat exchanger outlet of a heat exchanger comprising a gas cooler or condenser; 
 a first PX outlet fluidly coupled to a heat exchanger inlet of the heat exchanger; 
 a second PX inlet fluidly coupled to an evaporator outlet of an evaporator; and 
 a second PX outlet fluidly coupled to an evaporator inlet of the evaporator. 
   
     
     
         2 . The refrigeration system of  claim 1 , wherein the refrigeration system is configured to circulate carbon dioxide. 
     
     
         3 . The refrigeration system of  claim 1 , wherein:
 the first PX inlet is a high pressure (HP) inlet;   the first PX outlet is a HP outlet coupled to the heat exchanger inlet via a high pressure branch;   the second PX inlet is a low pressure (LP) inlet coupled to the evaporator outlet via a low pressure branch; and   the second PX outlet is a LP outlet.   
     
     
         4 . The refrigeration system of  claim 1 , wherein:
 the heat exchanger is configured to reject heat to environment;   the evaporator is configured to absorb heat from surroundings; and   a compressor is configured to increase fluid temperature and fluid pressure.   
     
     
         5 . The refrigeration system of  claim 1 , wherein:
 the heat exchanger is configured to receive and provide carbon dioxide in a supercritical state to a high pressure (HP) inlet of the PX responsive to a cooling operation; and   the PX is configured to:
 exchange pressure between the carbon dioxide in the supercritical state and superheated gaseous carbon dioxide, wherein the carbon dioxide in the supercritical state is converted within the PX to a two-phase gas/liquid mixture to exit a low pressure (LP) outlet of the PX to be provided to the evaporator, wherein the superheated gaseous carbon dioxide is to be converted within the PX to the carbon dioxide in the supercritical state to be provided to the heat exchanger. 
   
     
     
         6 . The refrigeration system of  claim 1  further comprising a compressor comprising:
 a compressor inlet fluidly coupled to the evaporator outlet; and 
 a compressor outlet fluidly coupled to the heat exchanger inlet. 
 
     
     
         7 . A refrigeration system comprising:
 a pressure exchanger (PX) comprising:
 a first PX inlet fluidly coupled to a heat exchanger outlet of a heat exchanger comprising a gas cooler or condenser; 
 a first PX outlet fluidly coupled to a second compressor inlet of a second compressor; 
 a second PX inlet fluidly coupled to a flash tank gas outlet of a flash tank, a first compressor outlet of a first compressor, and a second evaporator outlet of a second evaporator; and 
 a second PX outlet fluidly coupled to a flash tank inlet of the flash tank. 
   
     
     
         8 . The refrigeration system of  claim 7  further comprising:
 a first flow control valve disposed between a flash tank liquid outlet of the flash tank and a first evaporator inlet of a first evaporator; 
 a second flow control valve disposed between the flash tank liquid outlet of the flash tank and a second evaporator inlet of the second evaporator; and 
 a flash gas control valve disposed between the flash tank gas outlet and the second PX inlet. 
 
     
     
         9 . The refrigeration system of  claim 7  further comprising:
 a flow control valve disposed between a flash tank liquid outlet of the flash tank and a first evaporator inlet of a first evaporator; and 
 an expansion valve disposed between the heat exchanger outlet and the first PX inlet. 
 
     
     
         10 . The refrigeration system of  claim 9 , wherein the expansion valve is a Joule Thomson valve. 
     
     
         11 . The refrigeration system of  claim 7 , wherein at least one of:
 the refrigeration system is configured to circulate carbon dioxide; or   the PX is a rotary PX or a rotary liquid piston compressor LPC.   
     
     
         12 . The refrigeration system of  claim 7 , wherein:
 the first PX inlet is a high pressure (HP) inlet;   the first PX outlet is a HP outlet;   the second PX inlet is a low pressure (LP) inlet; and   the second PX outlet is a LP outlet.   
     
     
         13 . The refrigeration system of  claim 7 , wherein:
 a first evaporator is a low temperature (LT) load evaporator;   the first compressor is a LT compressor;   the second evaporator is a medium temperature (MT) load evaporator; and   the second compressor is a MT compressor.   
     
     
         14 . The refrigeration system of  claim 7 , wherein a first compressor inlet of the first compressor is fluidly coupled to a first evaporator outlet of a first evaporator, and wherein a second compressor outlet of the second compressor is fluidly coupled to a heat exchanger inlet of the heat exchanger. 
     
     
         15 . A refrigeration system comprising:
 a pressure exchanger (PX) comprising:
 a first PX inlet fluidly coupled to a heat exchanger outlet of a heat exchanger comprising a gas cooler or condenser; 
 a first PX outlet fluidly coupled to a heat exchanger inlet of the heat exchanger; 
 a second PX inlet fluidly coupled to a flash tank gas outlet of a flash tank; and 
 a second PX outlet fluidly coupled to a flash tank inlet of the flash tank. 
   
     
     
         16 . The refrigeration system of  claim 15  further comprising:
 a first flow control valve disposed between a flash tank liquid outlet of the flash tank and a first evaporator inlet of a first evaporator; 
 a second flow control valve disposed between the flash tank liquid outlet and a second evaporator inlet of a second evaporator; and 
 a flash gas control valve disposed between the flash tank gas outlet and the second PX inlet. 
 
     
     
         17 . The refrigeration system of  claim 15 , wherein at least one of:
 the refrigeration system is configured to circulate carbon dioxide; or   the PX is a rotary PX or a rotary liquid piston compressor LPC.   
     
     
         18 . The refrigeration system of  claim 15 , wherein:
 the first PX inlet is a high pressure (HP) inlet;   the first PX outlet is a HP outlet;   the second PX inlet is a low pressure (LP) inlet; and   the second PX outlet is a LP outlet.   
     
     
         19 . The refrigeration system of  claim 15  further comprising:
 a first evaporator that is a low temperature (LT) load evaporator; 
 a first compressor that is a LT compressor; 
 a second evaporator that is a medium temperature (MT) load evaporator; and 
 a second compressor that is a MT compressor. 
 
     
     
         20 . The refrigeration system of  claim 15 , wherein:
 a first compressor inlet of a first compressor is fluidly coupled to a first evaporator outlet of a first evaporator; and   a second compressor inlet of a second compressor is fluidly coupled to a first compressor outlet of the first compressor and a second evaporator outlet of a second evaporator; and   a second compressor outlet of the second compressor is fluidly coupled to the heat exchanger inlet; and   a flash tank liquid outlet of the flash tank is fluidly coupled to a first evaporator inlet of the first evaporator and a second evaporator inlet of the second evaporator.   
     
     
         21 . A refrigeration system comprising:
 a pressure exchanger (PX) comprising:
 a first PX inlet fluidly coupled to a flash tank gas outlet of a flash tank; 
 a first PX outlet fluidly coupled to a second compressor inlet of a second compressor; 
 a second PX inlet fluidly coupled to a first compressor outlet of a first compressor and a second evaporator outlet of a second evaporator; and 
 a second PX outlet fluidly coupled to the second PX inlet. 
   
     
     
         22 . The refrigeration system of  claim 21  further comprising:
 a first flow control valve disposed between a flash tank liquid outlet of a flash tank and a first evaporator inlet of a first evaporator; 
 a second flow control valve disposed between the flash tank liquid outlet and a second evaporator inlet of the second evaporator; and 
 an expansion valve disposed between a heat exchanger outlet of a heat exchanger and a flash tank inlet of the flash tank, the heat exchanger comprising a gas cooler or condenser. 
 
     
     
         23 . The refrigeration system of  claim 22 , wherein the expansion valve is a Joule Thomson valve. 
     
     
         24 . The refrigeration system of  claim 21 , wherein at least one of:
 the refrigeration system is configured to circulate carbon dioxide; or   the PX is a rotary PX or a rotary liquid piston compressor LPC.   
     
     
         25 . The refrigeration system of  claim 21 , wherein:
 the first PX inlet is a high pressure (HP) inlet;   the first PX outlet is a HP outlet;   the second PX inlet is a low pressure (LP) inlet; and   the second PX outlet is a LP outlet.   
     
     
         26 . The refrigeration system of  claim 21 , wherein:
 a first evaporator is a low temperature (LT) load evaporator;   the first compressor is a LT compressor;   the second evaporator is a medium temperature (MT) load evaporator; and   the second compressor is a MT compressor.   
     
     
         27 . The refrigeration system of  claim 21 , wherein:
 a first compressor inlet of the first compressor is fluidly coupled to a first evaporator outlet of a first evaporator;   a second compressor outlet of the second compressor is fluidly coupled to a heat exchanger inlet of a heat exchanger;   a flash tank inlet of the flash tank is fluidly coupled to a heat exchanger outlet of the heat exchanger; and   a flash tank liquid outlet of the flash tank is fluidly coupled to a first evaporator inlet of the first evaporator and a second evaporator inlet of a second evaporator.