The invention relates to an exhaust gas aftertreatment system for an internal combustion engine, in particular for a gasoline engine that is spark-ignited by means of spark plugs. A four -way catalytic converter and at least one three-way catalytic converter are situated in an exhaust gas system that is connected to an outlet of the internal combustion engine. An exhaust gas burner with which hot exhaust gas is introducible into the exhaust gas system directly downstream from the four-way catalytic converter is provided at an exhaust duct of the exhaust gas system. The exhaust gas burner is supplied with fresh air by a secondary air pump. The invention further relates to a method for exhaust aftertreatment of an internal combustion engine having such an exhaust gas aftertreatment system.

Methods and systems are provided for monitoring a change in exhaust particulate filter (PF) soot load during an engine non-combusting condition. In one example, a method may include, responsive to a higher than threshold PF temperature immediately prior to an engine shutdown, estimating a rate of soot burn when the engine is no longer combusting, and estimating a soot load on the PF during and at an onset of immediately subsequent engine start based in part on the rate of soot burn.

In a catalytic converter having a catalyst support that generates heat by being energized, short circuiting due to soot within exhaust is suppressed. A catalyst support is provided in a range of a glass coat layer that is provided on an inner surface of a tube body. A maximum diameter portion of an upstream side reduced diameter member and a maximum diameter portion of a downstream tube are positioned in the range of the glass coat layer.

There is provided an exhaust purification apparatus for an internal combustion engine in which a catalyst capable of adsorbing and oxidizing hydrocarbon is provided in an exhaust pipe, the exhaust purification apparatus including temperature detection means for detecting a temperature of the catalyst, estimation means for accumulating a time during which the temperature of the catalyst detected by the temperature detection means is equal to or less than a predetermined temperature, and estimating an amount of hydrocarbon adsorbed on the catalyst from the accumulated time, and control means for controlling fuel ejection of the internal combustion engine in a first ejection mode in which the temperature of the catalyst is increased to a temperature where hydrocarbons adsorbed on the catalyst are oxidized, in a case in which the amount of hydrocarbons estimated by the estimation means exceeds a predetermined upper limit.

Embodiments described herein methods can be used in particulate filter regeneration, such as particulate filters used for filtering the exhaust of an engine, e.g., a diesel engine. Systems herein can be configured to dispense combustion gas(es) into housing were a particulate filter is contained and to ignite the combustion gases. Methods for conducting a safety verification process of such systems are disclosed, as well as methods for regenerating the filters. Still other embodiments are described.

There is provided an exhaust purification apparatus for an internal combustion engine in which a catalyst capable of adsorbing and oxidizing hydrocarbon is provided in an exhaust pipe, the exhaust purification apparatus including temperature detection means for detecting a temperature of the catalyst, estimation means for accumulating a time during which the temperature of the catalyst detected by the temperature detection means is equal to or less than a predetermined temperature, and estimating an amount of hydrocarbon adsorbed on the catalyst from the accumulated time, and control means for controlling fuel ejection of the internal combustion engine in a first ejection mode in which the temperature of the catalyst is increased to a temperature where hydrocarbons adsorbed on the catalyst are oxidized, in a case in which the amount of hydrocarbons estimated by the estimation means exceeds a predetermined upper limit.

Aspects of the present invention relate to an exhaust system (207) for exhausting combustion gases from an internal combustion engine (101). The exhaust system (207) includes an exhaust conduit (215) for conveying exhaust gases from the internal combustion engine (101). A particulate filter (214) is providing for filtering particulates from the exhaust gases conveyed by the exhaust conduit (207). A supply inlet (216) is arranged to introduce gas into the particulate filter (214) to promote regeneration. The supply inlet (216) is disposed upstream of the particulate filter (214) and downstream of a catalytic convertor (209). A control valve (218) is provided for controlling the supply of gas to the particulate filter (214) to control regeneration. Aspects of the present invention also relate to a vehicle (100) incorporating a controller (104); and a method of controlling operation of the control valve (218) to control regeneration of the particulate filter (214).

Embodiments described herein methods can be used in particulate filter regeneration, such as particulate filters used for filtering the exhaust of an engine, e.g., a diesel engine. Systems herein can be configured to dispense combustion gas(es) into housing were a particulate filter is contained and to ignite the combustion gases. Methods for conducting a safety verification process of such systems are disclosed, as well as methods for regenerating the filters. Still other embodiments are described.