Non-aqueous heat transfer fluid and use thereof

Abstract

A non-aqueous, reduced toxicity diol based heat transfer fluid is provided comprised of at least one diol that acts as an antidote for ethylene glycol poisoning, such as for example propylene glycol. The heat transfer fluid may also include corrosion inhibitors that are soluble in the diols used for the heat transfer fluid. The heat transfer fluid may be used as a coolant in internal combustion engines such as automobile engines.

We claim:  
     
         1 . A method for cooling an internal combustion engine having a liquid based cooling system including at least one cooling chamber, at least one heat exchanger and at least one pump for circulating a heat transfer fluid, using a reduced toxicity, non-aqueous ethylene glycol based heat transfer fluid, said method comprising the steps of: 
 (a) substantially filling the cooling system with a non-aqueous heat transfer fluid comprising (1) ethylene glycol and (2) a sufficient amount of a diol that acts as an inhibitor to ethylene glycol poisoning when it is mixed with ethylene glycol to reduce the oral toxicity of the heat transfer fluid; and    (b) pumping the heat transfer fluid through the cooling system such that the heat transfer fluid absorbs heat in the cooling chamber that is produced by the internal combustion engine and releases the absorbed heat to the atmosphere through the heat exchanger.    
     
     
         2 . The method of  claim 1 , wherein the diol that acts as an inhibitor to ethylene glycol poisoning when it is mixed with ethylene glycol is propylene glycol.  
     
     
         3 . The method of  claim 2 , wherein the propylene glycol comprises at least 30 percent by weight of the ethylene glycol and propylene glycol in the heat transfer fluid.  
     
     
         4 . The method of  claim 2 , wherein the heat transfer fluid further comprises at least one corrosion inhibitor additive that is soluble in ethylene glycol and propylene glycol.  
     
     
         5 . The method of  claim 4 , wherein the corrosion inhibitor additive is selected from the group consisting of a molybdate salt, a nitrate salt and an azole.  
     
     
         6 . A method for cooling a heat generating device having a liquid based cooling system including at least one cooling chamber, at least one heat rejection apparatus and at least one pump for circulating a heat transfer fluid, using a reduced toxicity, non-aqueous ethylene glycol based heat transfer fluid, said method comprising the steps of: 
 (a) substantially filling the cooling system with a non-aqueous heat transfer fluid comprising (1) ethylene glycol and (2) a sufficient amount of a diol that acts as an inhibitor to ethylene glycol poisoning when it is mixed with ethylene glycol to reduce the oral toxicity of the heat transfer fluid; and    (b) pumping the heat transfer fluid through the cooling system such that the heat transfer fluid absorbs heat in the cooling chamber that is produced by the heat generating device and releases the absorbed heat to the atmosphere through the heat rejection apparatus.    
     
     
         7 . The method of  claim 6 , wherein the diol that acts as an inhibitor to ethylene glycol poisoning when it is mixed with ethylene glycol is propylene glycol.  
     
     
         8 . The method of  claim 7 , wherein the propylene glycol comprises at least about 30 percent by weight of the ethylene glycol and propylene glycol in the heat transfer fluid.  
     
     
         9 . The method of  claim 7 , wherein the heat transfer fluid is further comprises at least one corrosion inhibitor additive that is soluble in ethylene glycol and propylene glycol.  
     
     
         10 . The method of  claim 9 , wherein the corrosion inhibitor additive is selected from the group consisting of a molybdate salt, a nitrate salt and an azole.