| 摘要 |
A gaseous reductant injection control system for an exhaust aftertreatment is disclosed. According to an embodiment, a selective catalytic reduction (SCR) catalyst is in fluid communication with an exhaust stream generated from an engine. An oxidation catalyst (OC) is upstream of the SCR catalyst, and in fluid communication with the exhaust stream. A gaseous reductant injector is upstream of the SCR catalyst, and downstream of the OC and in fluid communication with the exhaust stream. A first gas sensor is upstream of the OC, and a second gas sensor is downstream of the SCR catalyst. A controller receives signals representative of the concentration of gases detected in the exhaust stream by the first gas sensor and the second gas sensor, and estimates the concentrations of nitric oxide (NO) and nitride dioxide (NO_2) in the exhaust stream therefrom. |
