Method and device for the regeneration of a particle filter arranged in the exhaust gas tract of an internal combustion engine
AssigneeMan Truck & Bus AG
InventorAndreas Döring
Life of this patent
Estimating the term…
Abstract
A method and to a device for the regeneration of a particle filter arranged in the exhaust gas tract of an internal combustion engine with at least one NO oxidation catalyst for the oxidation of NO, especially to NO2, which is arranged upstream of the particle filter and through which an exhaust gas stream flows. At least one heater, especially a heating catalyst, through which another gas stream, i.e., a second exhaust gas stream, flows and which heats the additional gas steam, is provided upstream of the particle filter. The heated additional gas stream is mixed upstream of the particle filter with the exhaust gas stream coming from the NO oxidation catalyst, i.e., the gas stream loaded in particular with NO2.
Claims15
A method for the regeneration of a particle filter arranged in the exhaust gas tract of an internal combustion engine, the method comprising:
- dividing an exhaust gas flow exiting the internal combustion engine into a first and a second exhaust gas stream;
- oxidizing the first exhaust gas stream by an oxidation catalyst configured for the oxidation of at least NO to NO2, the oxidation catalyst arranged in a first exhaust gas line upstream of the particle filter and through which the first exhaust gas stream flows;
- heating the second exhaust gas stream in a second exhaust gas line by at least one heater, configured as a heating catalyst to heat the second exhaust gas stream upstream of the particle filter, said first and second exhaust gas lines being parallel to each other;
- thereafter mixing the heated second exhaust gas stream with the first exhaust gas stream loaded with NO2 coming from the NO oxidation catalyst, said mixing being performed upstream of the particle filter;
- metering at predetermined times in predetermined quantities hydrocarbons into the second exhaust gas stream upstream of the at least one heater by a metering device;
- oxidizing the hydrocarbons;
- and
- supplying a predetermined amount of a charging-air stream to the second exhaust gas stream upstream of the heater during at least one of predetermined times, when an exhaust gas temperature exceeds a certain value, when lambda falls below a predetermined value, and when the oxygen falls below a predetermined value.
A device for the regeneration of a particle filter arranged in the exhaust gas tract of an internal combustion engine comprising:
- an exhaust gas line for conducting exhaust gas from the internal combustion engine, said exhaust gas line splitting into a first branch line for carrying a first exhaust gas stream and a second branch line for carrying a second exhaust gas stream;
- at least one NO oxidation catalyst disposed in said first branch line and configured for the oxidation of NO, arranged upstream of the particle filter and through which said first exhaust gas stream flows;
- at least one heater disposed in said second branch line and configured as a heating catalyst for oxidizing hydrocarbons arranged upstream of the particle filter and through which said second gas stream flows,
- said first and second branch line merging downstream of said NO oxidation catalyst and said heater so that said first gas stream and said second exhaust gas stream are supplied in a mixed state downstream of the NO oxidation catalyst and the heater to the particle filter;
- a metering device for metering at predetermined times in predetermined quantities hydrocarbons into the second exhaust gas stream upstream of the at least one heater;
- and
- a device for supplying a predetermined amount of a charging-air stream to the second exhaust gas stream upstream of the heater during at least one of predetermined times, when an exhaust gas temperature exceeds a certain value, when lambda falls below a predetermined value, and when the oxygen falls below a predetermined value.
Dependencies are inferred from the claim text.