Patent ID: 6347935
Filing Date: 2002-02-19
Classification: F23C,F23D,F23M

Abstract:
A round burner capable of reduced CO and NOx emissions comprising:a venturi tube for directing a flow of air through the burner and into a combustion zone in a combustion chamber through an entrance in a wall of the combustion chamber, said venturi tube having an inlet end, an outlet end and a throat having a lesser internal diameter than either of said ends located between said ends, said throat being operable when said flow of air passes through the venturi tube to create a low pressure zone therein, said venturi tube being positioned with its outlet end located adjacent said entrance to the combustion chamber, said venturi tube including a flue gas inlet connection located adjacent said throat for introducing recirculated flue gas directly into said low pressure zone; a swirler positioned in the venturi tube such that a primary portion of said flow of air passes therethrough, the arrangement of the outlet end of the venturi tube and the swirler being such that a secondary portion of said flow of air does not pass through the swirler; and a duct system including at least one inlet disposed in fluid communication with the combustion zone and at least one outlet connected to the flue gas inlet connection of the venturi tube, said system being arranged and adapted to recirculate a stream of flue gas from a location in said combustion chamber adjacent said combustion zone and into said flue gas inlet connection, whereby said stream of flue gas is inducted into said low pressure zone through said flue gas inlet connection and intermixed in the low pressure zone with said flow of air.