NOx reduction system for combustion exhaust gas

摘要

A NOx reduction system is provided which includes a NOx catalytic converter (28) mounted in an exhaust passage (26) of an engine (40), such as a diesel engine, and an air supply passage (31) that communicates with a portion of the exhaust passage located upstream of the NOx catalytic converter (28). The air supply passage supplies the exhaust passage (26) with a mixture of the air and cracked gas obtained by spraying fuel into the air and heating it up to 350 - 450 DEG C for partial oxidation thereof. With the mixture added to the exhaust gas, NOx contained in the exhaust gas can be effectively removed due to the NOx reducing capability of the cracked gas.