Patent ID: 7966812

Claim:
In an apparatus comprising an internal combustion engine, an exhaust system, a particulate filter disposed along the exhaust system, and an SCR catalyst that utilizes urea as reductant for NOx removal disposed along the exhaust system, a method of regenerating the particulate filter, comprising: exposing the catalyst and particulate filter to a first, lower elevated exhaust temperature for an interval to heat the catalyst to remove one or more of urea deposits and stored hydrocarbon from the catalyst, the interval based upon an estimated amount of urea deposited and hydrocarbon stored in the catalyst; increasing the temperature to a second, higher elevated exhaust temperature after removing a substantial portion of urea deposits and/or stored hydrocarbon from the catalyst; and exposing the catalyst and particulate filter to the second, higher elevated exhaust temperature to heat the particulate filter to remove particulate matter from the particulate filter.