Patent attributes
A method and apparatus for afterburning of hydrocarbon with air. Exhaust gas from a process in which hydrocarbon has been evolved is combusted with air to produce reduced NOX emissions. Hydrocarbon fuel is burned in an air mixture at an equivalence ratio of less than 1 oxygen to 1 hydrocarbon fuel (ER<1:1) above a temperature of about 900° C. in a burning zone for a sufficient time to combine substantially all of the oxygen in the fuel/air mixture with disassociated carbon and hydrogen components of the hydrocarbon fuel and to produce carbon dioxide, water, and a portion of unburned light hydrocarbons. The unburned light hydrocarbon gas is cooled in a cooling zone to below a relatively lower temperature of about 800° C. The unburned light hydrocarbon gas is oxidized substantially completely at less than a temperature of about 800° C. so that a reduced amount of thermal NOX results from the combustion and oxidation.