Abstract: A system for reducing an amount of at least one pollutant during combustion of fuel within a boiler having a wall is provided. The system includes at least one injector passing through at least one hole in the wall of the boiler, the injector being adapted to inject at least one pollutant reduction substance into the boiler. The injector is pivotable with respect to the wall of the boiler about at least one axis, such that an angle at which the pollutant reduction substance is injected into the boiler is variable.

Abstract: A tangential fired boiler includes a circumferential wall defining a combustion zone, the circumferential wall being generally rectangular when viewed along a generally horizontal cross-section. A fireball is disposed within the combustion zone, the fireball rotating about an imaginary axis when viewed along a generally horizontal cross-section. A corner member is disposed proximate to at least one corner of the combustion zone, with a plurality of fuel inlets disposed along the corner member. The plurality of fuel inlets inject fuel into the combustion zone, and at least some of the plurality of fuel inlets inject fuel in a direction which is angled with respect to a normal of the corner member and upstream relative to a direction of rotation of the fireball.

Abstract: A round burner capable of being operated with reduced CO and NOx emissions includes a venturi tube positioned to direct 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. The venturi tube has inlet and outlet ends and a throat. The outlet end of the venturi tube has a larger internal diameter than either the inlet end or the throat and the same is positioned adjacent the entrance to the combustion chamber. The inlet end of the venturi tube is also positioned further from the entrance than the outlet end of the venturi tube. The burner may include a duct system that includes an inlet disposed in fluid communication with the combustion zone and an outlet disposed in fluid communication with the venturi tube adjacent the throat thereof.