A fuel delivery system for use with a flow of heavy fuel oil for a gas turbine engine may include one or more fuel lines in communication with the gas turbine engine and a magnesium mixing system positioned upstream of the one or more fuel lines. The magnesium mixing system may include a flow of magnesium and a flow of a carrier fluid, a carrier mixing chamber to mix the flow of magnesium and the flow of the carrier fluid to form a mixed carrier flow, and a heavy fuel oil mixing chamber to mix the flow of heavy fuel oil and the mixed carrier flow.