REDUCING AGENT FEEDER OF INTERNAL COMBUSTION ENGINE AND METHOD OF PROMOTING SUBLIMATION OF REDUCING AGENT

摘要

PROBLEM TO BE SOLVED: To provide a reducing agent feeder of an internal combustion engine capable of easily gasifying a soiled reducing agent even when the atmosphere inside an exhaust pipe is not at a temperature sufficient for sublimation of solid urea. SOLUTION: The reducing agent feeder 1 is mounted in an exhaust pipe 2 o f a diesel engine for injecting a reducing agent to a selective reducing type NOx catalyst 4 for purifying NOx included in the exhaust gas. The reducing agent feeder 1 is mounted at a upstream position from the selective reducing type NOx catalyst 4 in the exhaust pipe 2. The reducing agent feeder 1 has a nozzle 10 for injecting a solid urea mixture liquid 8 comprising solid urea 5 which is a solid reducing agent originated from ammonium and light oil which is a water-in soluble solution for preventing the solid urea from absorbing water and fixing, and a solid urea sublimation promoting means which is a solid reducing agent sublimation promoting means for promoting sublimation of the solid urea 5 when the solid urea 5 is fed to the exhaust pipe 2 by injecting the solid urea mixture liquid 8 form the nozzle 10.