Three-phase emulsified fuel and methods of preparation and use

Abstract

The present invention relates to an air-water-hydrocarbon three-phase micro-emulsified fuel prepared by adding water, air, and emulsifier compositions to liquid hydrocarbon fuels, to the methods of preparation, and to the uses of the micro-emulsions. The three-phase micro-emulsion fuel is prepared by emulsifying heavy hydrocarbons such as bunker fuel oil and heavy petroleum from the fraction distillation of petroleum, with water or an aqueous solution, air, and emulsifier compositions, in which the hydrocarbon fuel and the air form a dispersed phase and the aqueous solution forms a continuous phase. The resulting emulsified fuel is to be used as an alternative energy fuel in internal combustion engines, boilers, heaters, furnaces, combustion turbines or power plants offering the advantages of lower viscosity, higher performance and cleaner burning than the original fuel.

What is claimed is: 
     
         1 . A micro-emulsion, comprising:
 about 70 to 85% by volume of a hydrocarbon fuel;   about 5 to 10% by volume of air; and   about 10 to 25% by volume of an aqueous solution comprising:
 a first emulsifying agent in an amount effective to separate and disperse the hydrocarbon fuel; and 
 a second emulsifying agent in an amount effective to stabilize the micro-emulsion, in which 
   the aqueous solution forms a continuous phase, the air forms a first dispersed phase and the hydrocarbon fuel forms a second dispersed phase.   
     
     
         2 . The micro-emulsion of  claim 1 , in which said hydrocarbon fuel is selected from the group consisting of heavy petroleum and fuel oil Nos. 4, 5, and 6. 
     
     
         3 . The micro-emulsion of  claim 2 , comprising about 85% by volume of the hydrocarbon fuel. 
     
     
         4 . The micro-emulsion of  claim 2 , comprising about 80% by volume of the hydrocarbon fuel. 
     
     
         5 . The micro-emulsion of  claim 1 , in which said micro-emulsion comprises a plurality of droplets each having a size in the range of about 10 to about 100 microns. 
     
     
         6 . The micro-emulsion of  claim 1 , wherein at least one of the first and second emulsifying agents includes anionic agents. 
     
     
         7 . The micro-emulsion of  claim 1 , wherein at least one of the first and second emulsifying agents includes nonionic agents. 
     
     
         8 . The micro-emulsion of  claim 1 , wherein at least one of the first and second emulsifying agents includes one or more of a detergent, a wetting agent, a dispersing agent, a surfactant, an agent improving lubricity, a mixing aid, and a heat stabilization aid. 
     
     
         9 . The micro-emulsion of  claim 1 , wherein at least one of the first and second emulsifying agents is present in an amount sufficient to stabilize the micro-emulsion for up to six months at room temperature. 
     
     
         10 . The micro-emulsion of  claim 1 , wherein the first emulsifying agent includes one or more of monoethanolamine, triethanol ammonium laurylsulphate, ethoxylate propoxylated fatty acid alcohol, coconut fatty betaine, and coconut alkylolamide. 
     
     
         11 . The micro-emulsion of  claim 10 , wherein the second emulsifying agent includes one or more of D-limonene, 4-nonylphenol ethoxylate, triethanol amine, sulfonic acid, and ethylene glycol. 
     
     
         12 . The micro-emulsion of  claim 1 , wherein at least some of the first dispersed phase substantially encapsulates at least some of the second dispersed phase. 
     
     
         13 . The micro-emulsion of  claim 12 , wherein the micro-emulsion has a viscosity at room temperature of between about 80 and about 200 cSt. 
     
     
         14 . The micro-emulsion of  claim 12 , wherein the micro-emulsion has a viscosity at 80° C. of less than about 40 cSt. 
     
     
         15 . A method of preparing a three-phase micro-emulsion comprising:
 combining a hydrocarbon fuel and an aqueous solution;   agitating the combined hydrocarbon fuel and aqueous solution in the presence of a first emulsifying agent while introducing air at a first flow rate to form an intermediate mixture; and   agitating the intermediate mixture in the presence of a second emulsifying agent while introducing air at a second flow rate to form the three-phase micro-emulsion in which the hydrocarbon fuel and air form dispersed phases and the aqueous solution forms a continuous phase.   
     
     
         16 . The method of  claim 15 , further comprising terminating agitation upon achieving a predetermined viscosity value for the micro-emulsion. 
     
     
         17 . The method of  claim 16 , further comprising adding at least one of the first and second emulsifying agents in an amount of about 0.4 to about 0.8% by volume of the hydrocarbon fuel. 
     
     
         18 . The method of  claim 17 , wherein at least one of the first and second emulsifying agents comprises one or more of D-limonene, 4-nonylphenol ethoxylate, triethanol amine, sulfonic acid, and ethylene glycol. 
     
     
         19 . The method of  claim 17 , wherein at least one of the first and second emulsifying agents comprises one or more of monoethanolamine, triethanol ammonium laurylsulphate, ethoxylate propoxylated fatty acid alcohol, coconut fatty betaine, and coconut alkylolamide. 
     
     
         20 . The method of  claim 15 , further comprising:
 proportioning the hydrocarbon fuel and the aqueous solution in a ratio between about 70%-30% and about 85%-15%.   
     
     
         21 . The method of  claim 20 , further comprising:
 proportioning the hydrocarbon fuel and the aqueous solution in a ratio of about 80%-20%.   
     
     
         22 . The method of  claim 15 , wherein agitating comprises pneumatically agitating for between about 1 and 2 hours. 
     
     
         23 . The method of  claim 24 , wherein the predetermined viscosity value comprises about 80 to 200 cSt at room temperature. 
     
     
         24 . The method of  claim 23 , wherein the predetermined viscosity value comprises less than about 40 cSt at 80° C. 
     
     
         25 . The method of  claim 15 , further comprising pumping the micro-emulsion.