Method for operating exhaust gas after-treatment system of selective catalytic reduction catalyzer of internal combustion engine, involves forming primary estimated value of primary measurement of existing and easily releasable hydrocarbons

摘要

The method involves forming a primary estimated value of a primary measurement of the existing and easily releasable hydrocarbons. A secondary estimated value of a secondary measurement is formed from the hydrocarbons releasable in a difficult manner. An exhaust gas after-treatment operation is triggered at higher exhaust temperature based on the primary estimated value or the secondary estimated value which exceeds a threshold value. An independent claim is also included for a control unit for controlling the operation of an exhaust gas after-treatment system of a selective catalytic reduction catalyzer of an internal combustion engine.