Secondary air injection

About: Secondary air injection is a research topic. Over the lifetime, 11452 publications have been published within this topic receiving 112147 citations.

Method and system for reducing NOx and fuel emissions in a furnace

Abstract: In a method of this invention, a first oxidant flow including oxygen and/or air, is injected into an exhaust gas flow from a primary burn zone in a furnace combustion chamber. The first oxidant flow is injected into the exhaust gas flow in a secondary burn zone downstream from the primary burn zone, but inside of the furnace chamber so that heat released from combustion of the first oxidant flow can be used for the purpose to which the furnace is applied. Also, the injection of the first oxidant flow into the secondary burn zone combusts fuel pollutants that might otherwise be released from the furnace into the atmosphere. The method can also include mixing a gaseous hydrocarbon fuel flow with the exhaust gas flow from the secondary burn zone to reduce the NOx, level in the exhaust gas. Also, the method can include mixing a second oxidant flow including air and/or oxygen, with the exhaust gas, preferably after reducing the NOx. If the furnace is a regenerative type, the air flow can be mixed with the exhaust gas flow in proximity to the entrance of a regenerator to heat the regenerator. The invention also includes a related system.

Exhaust gas post treatment system

Abstract: Exhaust gas post treatment system for nitrogen oxide and particle reduction of an internal combustion engines operated with excess air. An oxidation catalytic converter is disposed in the exhaust gas stream of the engine for converting at least a portion of the nitric oxide of the exhaust gas into nitrogen dioxide. A metering device adds reduction agent to the exhaust gas stream downstream of the oxidation catalytic converter and/or to a partial exhaust gas stream branched off upstream of the oxidation catalytic converter and returned to the exhaust gas stream downstream thereof. The reduction agent is ammonia or a material that releases ammonia downstream of the supply location due to the hot exhaust gas. A particle separator or filter is disposed in the exhaust gas stream downstream of the oxidation catalytic converter and of the supply location, and converts carbon particles accumulated in the separator or filter into carbon monoxide, carbon dioxide, nitrogen and nitric oxide with the aid of nitrogen dioxide in the exhaust gas stream. An SCR catalytic converter is disposed downstream of the separator or filter for reducing nitrogen oxides in the exhaust gas stream into nitrogen and water vapor with the aid of ammonia or released ammonia by selective catalytic reduction.

Exhaust gas recirculating device

Abstract: An exhaust gas recirculation device in accordance with the present invention has an exhaust gas recirculation valve interposed between the exhaust system and the intake system of an internal combustion engine, an exhaust gas recirculation cooler for cooling exhaust gas sent from the exhaust gas recirculation valve to the intake system, and a bypass valve that bypasses the exhaust gas recirculation cooler and sends the exhaust gas to the intake system. The exhaust gas recirculation cooler is put adjacently between the exhaust gas recirculation valve and the bypass valve.