Patent ID: 8151556

Claim:
An internal combustion engine comprising an exhaust system through which exhaust gas created by combustion in engine combustion chambers passes to atmosphere and which comprises an after-treatment system that treats the exhaust gas before the exhaust gas leaves the exhaust system, wherein the after-treatment system comprises: an exhaust flow path having an entrance through which exhaust gas enters the after-treatment system and an exit through which exhaust gas exits the after-treatment system; an SCR catalyst disposed in the exhaust flow path; partition wall structure that is disposed in the exhaust flow path upstream of the SCR catalyst to define multiple independent channels for separating exhaust gas flowing toward the SCR catalyst into multiple detached exhaust gas flow streams; for each independent channel, at least one respective data port via which data for at least one characteristic of a respective detached exhaust gas flow stream can be obtained; for each independent channel, a respective reductant port through which reductant can be introduced into a respective detached exhaust gas flow stream; a reductant supply system; and a processor for processing data from at least one data port for each respective independent channel and for using a result of the processing of data from at least one data port for each respective independent channel to cause an appropriate quantity of reductant from the reductant supply system to be introduced into the respective detached exhaust gas flow stream to create a resulting mixture for enabling the SCR catalyst to reduce NOx in the mixture without contributing a significant excess of reductant to flow leaving the SCR catalyst.