Exhaust emission purifying apparatus for engine

摘要

An exhaust emission purifying apparatus for an engine comprising:
a reduction catalytic converter (5) disposed in an exhaust system of the engine, for reductively purifying nitrogen oxides in exhaust emission with a reducing agent;
an injection nozzle (7) arranged for injection-supplying the reducing agent to an upstream side of the exhaust emission flow with respect to the reduction catalytic converter within an exhaust passage (3) of the exhaust system; and
a reducing agent supply device (8) arranged for supplying the reducing agent to the injection nozzle (7),
wherein the apparatus further comprises blocking means which is detachably disposed for blocking an exhaust passage portion between a portion of the exhaust passage (24), to which the reducing agent injection-supplied from said injection nozzle (7) is attached, and another portion of the exhaust passage (25), on which at least said reduction catalytic converter (5) is disposed, and a feed port (21) for feeding washing water and a drain port (22) for drainage of the washing water are provided on a wall portion of the exhaust passage at the portion to which said reducing agent is attached.