EXHAUST EMISSION CONTROL SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide an exhaust emission control system improving NOx purification performance as the whole at the time of operation.SOLUTION: An exhaust emission control system includes: a NOx purification catalyst that has a NOx adsorbent; an electric discharge device that performs electric discharge to the NOx adsorbent; active oxygen consumption means that consumes active oxygen in the ambient atmosphere of the NOx adsorbent; and control means that starts the operation of the electric discharge device when it is determined to be the time right before an integration inflow NOx amount to the NOx adsorbent reaches a saturation NOx adsorption amount of the NOx adsorbent, and completes the operation of the electric discharge device when it is determined to be the time right after NOx adsorbed to the NOx adsorbent is purified.