Patent ID: 9429060
Filing Date: 2016-08-30
CPC Classification: B01D,F01N,Y02A,Y02C,Y02T

Claim Text:
1. A method, comprising: producing an exhaust gas in an exhaust flow path including a selective catalytic reduction (SCR) catalyst, wherein producing the exhaust gas includes operating an internal combustion engine; determining a temperature condition of the exhaust gas; determining an engine shut-down condition, wherein the engine shutdown condition includes a pre-shutdown condition and a post-shutdown condition; and selectively providing one of a gaseous reductant released from a dry reductant source and a liquid reductant from a liquid reductant source to the exhaust flow path upstream of the SCR catalyst in response to the engine shutdown condition, wherein the gaseous reductant is provided from the dry reductant source in response to the post-shutdown condition and the liquid reductant is provided from the liquid reductant source in response to the pre-shutdown condition.