Patent ID: 8505280
Filing Date: 2013-08-13
Classification: F01N,F02D,Y02A,Y02T

Abstract:
1. A process for controlling the injection of urea for treatment of nitrogen oxides in a selective catalytic reduction system (SCR) intended to be installed in an exhaust line of an engine of an automotive vehicle, the treatment comprises chemically reducing in an SCR catalyst, nitrogen oxides by adding ammonia contained in urea; the process comprising the following steps: (a) first measuring of the temperature of the gases in the exhaust line of the engine, upstream of the SCR catalyst, then, after measuring the temperature of the gases: (b) injecting urea into the exhaust line if the measured temperature is greater than a predetermined minimum injection temperature, (c) performing steps (c)(i)-(c)(v) if the measured temperature is lower than the minimum injection temperature: