Abstract: A method for combusting a fuel in a cyclone combustor having a burner and a barrel includes: feeding a stream of the fuel into the barrel at the burner end of the barrel; feeding a stream(s) of a first oxidant (e.g., air) having a first oxygen concentration into the barrel at a first flowrate, the stream(s) of the first oxidant including a predominant stream; feeding a stream(s) of a second oxidant (e.g., oxygen) having a second oxygen concentration into the barrel at a second flowrate and in a selective manner, whereby a portion of the first oxidant combines with a portion of the second oxidant, thereby forming a combined oxidant having a combined oxygen concentration, and a portion of the first oxidant from the predominant stream continues having the first oxygen concentration; and combusting a portion of the fuel with a portion of the combined oxidant in the barrel.

Abstract: Combustion of petroleum coke using air to carry the fuel into a combustion zone and to provide a source of oxidant. Enhanced combution utilizes oxygen introduced into or proximate primary, secondary, tertiary, quaternary, or over-fire air to effect primary combustion of the fuel. Petroleum coke fuel in an oxygen supported air-petroleum coke combustion process can be used to re-power a utility boiler.