Patent ID: 8899969

Claim:
A method for dual-fuel combustion comprising the steps of: pressurizing a liquid fuel, wherein a means of pressurizing the liquid fuel comprises a low pressure liquid fuel inlet and a high pressure liquid fuel outlet; preheating the pressurized liquid fuel, wherein a means of preheating the pressurized liquid fuel comprises at least one of an electric liquid fuel preheater, a water-liquid fuel preheater, and a steam-liquid fuel preheater; wherein said pressurized liquid fuel preheating means further comprises a water-fuel heater having a pressurized preheated liquid fuel inlet in fluid communication with said means of preheating the pressurized liquid fuel and having a pressurized preheated water inlet in fluid communication with a pressurized water preheater; atomizing the preheated liquid fuel, producing an atomized liquid fuel; flash vaporing up to about 50% of said atomized liquid fuel, producing a liquid fuel mixture comprising said atomized liquid fuel and a vaporized fuel; mixing said liquid fuel mixture with a primary combustion oxidant in a mixing chamber, producing a fuel/oxidant mixture having a primary stoichiometry less than about 1.0; introducing said fuel/oxidant mixture into a first combustion chamber in which partial combustion of said fuel/oxidant mixture occurs, producing a secondary fuel gas; cooling said secondary fuel gas, producing a cooler secondary fuel gas; mixing said cooler secondary fuel gas with a secondary combustion oxidant, producing a secondary fuel gas/oxidant mixture; introducing said secondary fuel gas/oxidant mixture into a second combustion chamber in which substantially complete combustion of said secondary fuel gas/oxidant mixture occurs, producing flue gases; and venting said flue gases from said second combustion chamber.