Patent ID: 8627651

Claim:
A method, comprising: interpreting an exhaust temperature value, an ambient temperature value, and a urea injection amount; in response to the exhaust temperature value, the ambient temperature value, and the urea injection amount, determining a urea deposit amount; in response to the urea deposit amount exceeding a urea deposit threshold, initiating a desoot regeneration event comprising operating an engine at a urea decomposition exhaust temperature; determining that a stored NH 3 amount on an SCR catalyst exceeds a first threshold, that a stored particulate amount on a particulate filter exceeds a second threshold, and performing a NO x -based regeneration of the particulate filter, the NO x -based regeneration comprising operating the engine at a NO x -based soot oxidation temperature; and maintaining the stored NH 3 amount below a third threshold whenever stored particulates are available on the particulate filter.