Subcritical Carbon Dioxide Dehumidifier

Abstract

A subcritical carbon dioxide dehumidifier having a compressor, a condenser, a receiver, an expansion valve, an evaporator, and an expansion tank and using carbon dioxide as a refrigerant.

What is claimed is: 
     
         1 . A subcritical carbon dioxide dehumidifier, comprising a compressor, a condenser, a receiver, an expansion valve, an evaporator, and an expansion tank and connections therebetween forming a closed refrigeration circuit. 
     
     
         2 . The subcritical carbon dioxide dehumidifier of  claim 1 , wherein the compressor, condenser, receiver, expansion valve, evaporator, and the connections therebetween define a main line. 
     
     
         3 . The subcritical carbon dioxide dehumidifier of  claim 2 , wherein the main line has a high-pressure side between the compressor and the expansion valve and a low-pressure side between the expansion valve and the compressor. 
     
     
         4 . The subcritical carbon dioxide dehumidifier of  claim 3 , having a secondary line that connects to the main line by a first connection and a second connection, and wherein the expansion tank is located on the secondary line. 
     
     
         5 . The subcritical carbon dioxide dehumidifier of  claim 4 , wherein the first connection connects to the high-pressure side of the main line and the second connection connects to the low-pressure side of the main line. 
     
     
         6 . The subcritical carbon dioxide dehumidifier of  claim 5 , wherein the first connection connects between the evaporator and the compressor. 
     
     
         7 . The subcritical carbon dioxide dehumidifier of  claim 6 , wherein the second connection connects between the condenser and the receiver. 
     
     
         8 . The subcritical carbon dioxide dehumidifier of  claim 7 , having a control valve on the first connection that selectively prevents the flow of carbon dioxide into the expansion tank. 
     
     
         9 . The subcritical carbon dioxide dehumidifier of  claim 8 , wherein the control valve is a normally open solenoid valve. 
     
     
         10 . The subcritical carbon dioxide dehumidifier of  claim 9 , having one or more pressure relief valves on the main line. 
     
     
         11 . The subcritical carbon dioxide dehumidifier of  claim 10 , having a pressure relief valve on the expansion tank. 
     
     
         12 . The subcritical carbon dioxide dehumidifier of  claim 11 , having a filter on the main line, located between the receiver and the expansion valve.