Sorption cooling systems and climate control using multi-channel thermal swing adsorption

Abstract

Sorption cooling systems and methods for using sorption cooling systems, particularly to control the interior climate of vehicles, buildings, appliances and other enclosed spaces. The sorption cooling systems may incorporate sorbent beds having a low thermal mass that are capable of rapid cycle times to increase the efficiency of the sorption cooling systems.

What is claimed is: 
     
         1 . An adsorbent bed, comprising:
 a fluid impermeable casing comprising a refrigerant inlet, a refrigerant outlet, a coolant inlet and a coolant outlet;   a first desiccant sheet comprising a first aperture therethrough and a first adsorbent side; and   a second desiccant sheet comprising a second aperture therethrough and a second adsorbent side;   a refrigerant flow path for flowing a refrigerant fluid between said refrigerant inlet and refrigerant outlet, said refrigerant path being at least partially defined by said first and second adsorbent sides; and   a coolant flow path for flowing a coolant fluid between said coolant inlet and said coolant outlet, said coolant flow path being fluidly isolated from said refrigerant flow path and being adjacent to at least one of said first and second desiccant sheets;   wherein said first and second absorbent sheets comprise a hydrophobic polymer and a desiccant salt.   
     
     
         2 . An adsorbent bed as recited in  claim 1 , wherein the hydrophobic polymer is PTFE. 
     
     
         3 . An adsorbent bed as recited in  claim 1 , wherein the first and second desiccant sheets have a thickness of not greater than about 0.25 mm. 
     
     
         4 . An adsorbent bed as recited in  claim 1 , wherein the refrigerant flow path comprises mesh spacers. 
     
     
         5 . An adsorbent bed, comprising:
 a fluid impermeable casing comprising a refrigerant inlet, a refrigerant outlet, a coolant inlet and a coolant outlet;   a first desiccant sheet comprising a first aperture therethrough and a first adsorbent side; and   a second desiccant sheet comprising a second aperture therethrough and a second adsorbent side;   a refrigerant flow path for flowing a refrigerant fluid between said refrigerant inlet and refrigerant outlet, said refrigerant path being at least partially defined by said first and second adsorbent sides; and   a coolant flow path for flowing a coolant fluid between said coolant inlet and said coolant outlet, said coolant flow path being fluidly isolated from said refrigerant flow path and being adjacent to at least one of said first and second desiccant sheets;   wherein the coolant flow path is formed by a pressure differential between the flowing refrigerant fluid and the flowing coolant fluid.   
     
     
         6 . An adsorbent bed as recited in  claim 5 , wherein the refrigerant flow path comprises mesh spacers. 
     
     
         7 . A closed-loop sorption cooling system, comprising:
 an evaporator;   a condenser adapted for fluid communication with said evaporator; and   at least first and second adsorbent beds adapted for fluid communication with said condenser and said evaporator, each adsorbent bed comprising:
 a fluid impermeable casing comprising a refrigerant inlet, a refrigerant outlet, a coolant inlet and a coolant outlet; 
 a first desiccant sheet comprising a first aperture therethrough and a first adsorbent side; and 
 a second desiccant sheet comprising a second aperture therethrough and a second adsorbent side; 
 a refrigerant flow path for flowing a refrigerant fluid between said refrigerant inlet and refrigerant outlet, said refrigerant path being at least partially defined by said first and second adsorbent sides; and 
 a coolant flow path for flowing a coolant fluid between said coolant inlet and said coolant outlet, said coolant flow path being fluidly isolated from said refrigerant flow path and being adjacent to at least one of said first and second desiccant sheets; 
   wherein said first and second adsorbent beds have a cooling capacity of at least 1 kW per 350 grams of adsorbent (e.g., desiccant), such as at least 1 kW of cooling per 200 grams of adsorbent, and even at least 1 kW of cooling per 150 grams of adsorbent.   
     
     
         8 . The closed loop sorption cooling system of  claim 7 , wherein the system comprises no more than said first and second absorbent beds. 
     
     
         9 . A method for sorption cooling utilizing a an evaporator, a condenser adapted for fluid communication with said evaporator and at least first and second adsorbent beds adapted for fluid communication with said condenser and said evaporator, comprising the steps of:
 adsorbing a refrigerant in the first adsorbent bed;   during said adsorbing step, desorbing a refrigerant from the second adsorbent bed; and   during said adsorbing step and after said desorbing step, cooling the second adsorbent bed.   
     
     
         10 . A method as recited in  claim 9 , wherein said refrigerant comprises water. 
     
     
         11 . A method as recited in  claim 9 , wherein said desorbing step comprises heating the second absorbent bed using waste heat. 
     
     
         12 . A method as recited in  claim 11 , wherein the waste heat is derived from a vehicle engine. 
     
     
         13 . A method as recited in  claim 11 , wherein the waste heat is derived from a cogeneration facility.