Life support system

Abstract

A life support system includes a refuge housing and a cooling system. The cooling system, which has a supply of liquefied gas and a cooling circuit, is operatively associated with the refuge housing. The supply of liquefied gas is operatively associated with the cooling circuit that contains a heat exchanger, a fan motor and a fan operatively associated with the fan motor. A conduit connects the heat exchanger to the fan motor that is driven by waste gas generated through a phase change of the liquefied gas in the heat exchanger.

1 . A life support system, comprising:
 a refuge housing; and   a cooling system operatively associated with the refuge housing, the cooling system having a supply of liquefied gas and a cooling circuit, the supply of liquefied gas being operatively associated with the cooling circuit, the cooling circuit comprising a heat exchanger, a fan motor and a fan operatively associated with the fan motor, and a first conduit connecting the heat exchanger to the fan motor, the fan motor being driven by waste gas generated through a phase change of the liquefied gas in the heat exchanger.   
   
   
       2 . The life support system of  claim 1 , wherein the heat exchanger comprises a primary heat exchanger and a secondary heat exchanger. 
   
   
       3 . The life support system of  claim 1 , wherein the liquefied gas is carbon dioxide. 
   
   
       4 . The life support system of  claim 2 , wherein the primary heat exchanger and the secondary heat exchanger are arranged in series. 
   
   
       5 . The life support system of  claim 1 , further comprising a carbon dioxide scrubbing system including a plurality of chemical cartridges for removing the carbon dioxide in air. 
   
   
       6 . The life support system of  claim 5 , wherein the carbon dioxide scrubbing system comprises a scrubber motor operatively associated with a blower, a second conduit connecting the scrubber motor to the heat exchanger, the scrubber motor being driven by the waste gas. 
   
   
       7 . A cooling system comprising:
 at least one tank of liquefied gas;   a cooling circuit connected to the at least one tank by a supply conduit for supplying the liquefied gas to the cooling circuit, the cooling circuit comprising a heat exchanger configured to convert the liquefied gas to waste gas, a fan and a fan motor powered by the waste gas to turn the fan;   a delivery unit having a fan port and at least one air port, the delivery unit housing the heat exchanger, the fan and the fan motor; and   the fan motor and fan being configured to draw air through the at least one air port and through the heat exchanger and blow cooled air out the fan port.   
   
   
       8 . The cooling system of  claim 7 , wherein the heat exchanger comprises a primary heat exchanger and a secondary heat exchanger. 
   
   
       9 . The cooling system of  claim 8 , wherein the primary heat exchanger and the secondary heat exchanger are arranged in parallel. 
   
   
       10 . The cooling system of  claim 8 , wherein the primary heat exchanger and the secondary heat exchanger are arranged in series. 
   
   
       11 . The cooling system of  claim 7 , further comprising:
 a back pressure regulator, the back pressure regulator being disposed between an outlet end of the heat exchanger and the fan motor.   
   
   
       12 . The cooling system of  claim 7 , further comprising an expansion valve, the expansion valve being disposed between an inlet end of the heat exchanger and the at least one tank. 
   
   
       13 . The cooling system of  claim 7 , wherein the at least one tank comprises a tank array. 
   
   
       14 . The cooling system of  claim 7 , wherein the fan motor and the fan are not connected to a conventional power source. 
   
   
       15 . The cooling system of  claim 7 , wherein the liquefied gas is carbon dioxide. 
   
   
       16 . A method of cooling a confined area without a conventional power source, comprising:
 supplying a cooling circuit with liquefied gas from at least one tank set at a first pressure, the cooling circuit comprising a heat exchanger;   causing the liquefied gas to expand, resulting in expanded liquefied gas;   allowing the expanded liquefied gas to convert to waste gas in the heat exchanger;   using waste gas to turn a fan, thereby drawing air from the confined area across the heat exchanger, creating cooled air; and   using the fan, blowing the cooled air into the confined area.   
   
   
       17 . The method of  claim 16 , further comprising:
 evaluating a thermodynamic property of the confined area to calculate a result; and   using the result to set the first pressure for the at least one tank.   
   
   
       18 . The method of  claim 16 , wherein using waste gas to turn a fan comprises supplying waste gas to a fan motor operatively associated with the fan. 
   
   
       19 . The method of  claim 16 , wherein:
 the heat exchanger comprises a primary heat exchanger and a secondary heat exchanger; and   drawing air from the confined area across the heat exchanger comprises drawing air from the confined area across the secondary heat exchanger, creating partially-cooled air, and drawing the partially-cooled air across the primary heat exchanger, creating cooled air.   
   
   
       20 . The method of  claim 16 , wherein the cooling circuit comprises a pressure gauge and further comprising:
 monitoring the pressure gauge for a reading;   comparing the reading to a trouble-shooting guide for the cooling system to make a determination;   using the determination to identify a defective component of the cooling system; and   replacing the defective component.