Patent ID: 8443590

Claim:
An exhaust treatment system comprising: a particulate matter (PM) filter that receives exhaust gas of an engine and filters PM from the exhaust gas, wherein the PM filter includes M zones; an electric heater arranged to cover a first one of the M zones but not other ones of the M zones, wherein the electric heater heats exhaust gas that is input to the first one of the M zones but not the other ones of the M zones, and wherein M is an integer greater than one; and a control module configured to i) adjust an exhaust temperature to a first predetermined temperature and activates the electric heater to initiate regeneration in the first one of the M zones, ii) deactivate the electric heater, and iii) after deactivating the electric heater, adjust the exhaust temperature to a second predetermined temperature that is greater than the first predetermined temperature to initiate regeneration in the other ones of the M zones, wherein the first one of the M zones includes an axially centered portion of the PM filter, and wherein the other ones of the M zones include a remaining portion of the PM filter surrounding the first one of the M zones.