Abstract: An apparatus and method for high velocity injection of a stream of fluid fuel into a stream of NOx containing combustion effluents downstream of a primary combustion zone, without the use of recirculated flue gas or other carrier gas. The apparatus includes a fuel introducing member that has a fuel receiving end for receiving fluid fuel from a fuel source and a fuel injection end for injecting the fluid fuel into the stream of combustion effluents. A fuel passage is in fluid communication with the fuel receiving end and the fuel injection end of the fuel introducing member. A means for increasing the velocity of the fluid fuel, without the need of a carrier gas, is associated with the fuel introducing member.

Abstract: A method and apparatus are provided for selectively oxidizing carbon monoxide in the presence of hydrogen gas while leaving the hydrogen substantially unoxidized. This method utilizes a catalytic material, such as copper/copper oxide, silver/silver oxide, nickel/nickel oxide, and the higher and lower oxides of cerium, which in a more oxidized state is readily reduced by carbon monoxide and which in a more reduced state is readily oxidized by air. A carbon monoxide/hydrogen gas mixture and air are alternately contacted with the catalytic material, such that the carbon monoxide is selectively oxidized and the catalytic material is regenerated.

Abstract: Various methods for decreasing the amount of nitrogen oxides released to the atmosphere as a component of combustion gas mixtures are provided. The methods specifically provide for the removal of nitric oxide and nitrogen dioxide (NOx) from gas mixtures emitted from stationary combustion systems. In particular, methods for improving efficiency of nitrogen oxide reduction from combustion systems include injecting metal-containing compounds into the main combustion zone and/or the reburning zone of a combustion system. The metal containing compounds react with active combustion species, and these reactions change radical concentrations and significantly improve NOx conversion to molecular nitrogen. The metal-containing additives can be injected with the main fuel, in the main combustion zone, with secondary or reburning fuel addition, or at several locations in the main combustion zone and reburning zone.

Abstract: A self cleaning port system and method provides for removal of ash deposits and build-up from around a port opening in a combustion device such as an industrial or utility furnace or boiler. The self cleaning port system includes a port structure for providing communication between a source of injected material and an interior portion of the combustion device. The port structure can be a burner for injecting fuel and air, an overfire air port, a flue gas recirculation port, a reburning port for injecting a reburning fuel, a pollutant emission control port for injecting NO.sub.x or SO.sub.2 reduction agents, or other types of ports. A blowing member such as a lance is disposed within or formed as part of the port structure and is configured to discharge a blowing medium so as to remove ash deposits adjacent to the port opening. The blowing medium is discharged from the blowing member such that the blowing medium is directed outwardly away from the port opening.