Abstract: A method of direct flame incineration of a polluted air effluent, such as the effluent from a coffee roasting oven. The method is employed in apparatus comprising a cylindrical housing containing three concentric longitudinally aligned shells, each of which defines a respective combustion zone, and with the outermost shell defining with the housing an effluent heat exchange passageway to receive the effluent from an effluent inlet. A fuel gas or oil nozzle directs a spray of fuel forwardly into the first innermost shell, with primary air also flowing into the first shell to provide initial combustion of the resulting air-fuel mixture. The effluent flowing from the heat exchange passageway flows partly through an annular secondary inlet into the combustion zone of the second intermediate shell, and partly through an annular tertiary passageway into the final combustion zone of the third outermost shell.

Abstract: An apparatus and method for direct flame incineration of a polluted air effluent, such as the effluent from a coffee roasting oven. The apparatus comprises a cylindrical housing containing three concentric longitudinally aligned shells, each of which defines a respective combustion zone, and with the outermost shell defining with the housing an effluent heat exchange passageway to receive the effluent from an effluent inlet. A fuel gas or oil nozzle directs a spray of fuel forwardly into the first innermost shell, with primary air also flowing into the first shell to provide initial combustion of the resulting air-fuel mixture. The effluent flowing from the heat exchange passageway flows partly through an annular secondary inlet into the combustion zone of the second intermediate shell, and partly through an annular tertiary passageway into the final combustion zone of the third outermost shell.