A control module for an aftertreatment system that includes a selective catalytic reduction (SCR) catalyst and an oxidation catalyst, comprises a controller configured to be operatively coupled to the aftertreatment system. The controller is configured to determine an actual SCR catalytic conversion efficiency of the SCR catalyst. The controller determines an estimated SCR catalytic conversion efficiency based on a test sulfur concentration selected by the controller. In response to the estimated SCR catalytic conversion efficiency being within a predefined range, the controller sets the test sulfur concentration as a determined sulfur concentration in a fuel provided to the engine. The controller generates a sulfur concentration signal indicating the determined sulfur.

Disclosed is a method for diagnosing a first exhaust treatment component for treatment of an exhaust gas stream comprising means for oxidizing nitric oxide into nitrogen dioxide. A first reduction catalytic converter is arranged upstream said means for oxidizing nitric oxide into nitrogen dioxide, and a second reduction catalytic converter is arranged downstream said means. A reagent is for reduction of nitrogen oxides in said first catalytic converter, and a first sensor measures an occurrence of nitrogen oxide downstream said means but upstream said second reduction catalytic converter. The method comprises: causing a supply of reagent upstream said first reduction catalytic converter to an extent exceeding the extent to which reagent is consumed by the first reduction catalytic converter, determining a first measure of the occurrence of reagent downstream said means for oxidizing, and diagnosing said means for oxidizing nitric oxide into nitrogen dioxide based on said first measure.

The invention relates to a method involving the treatment of the pollutants emitted by a vehicle having a heat engine, in which catalyst means (3) are heated, characterised in that the amount of oxygen (OS) in the catalyst means (3) is controlled to be over a minimum amount of oxygen (OS1) by injecting air upstream of said catalyst means (3).

Systems and apparatuses include a selective catalytic reduction system structured to receive exhaust gases from a dual fuel engine system and include a diesel exhaust fluid dosing unit, an ammonia slip catalyst positioned directly downstream of the selective catalytic reduction catalyst, an oxidation catalyst positioned directly downstream of the ammonia slip catalyst, and one or more processing circuits. The circuits receive a system out NOx value, a space velocity, an ammonia to NOx ratio, an exhaust temperature, a substitution rate, and a conversion efficiency target. The circuits determine a conversion efficiency differential, adjust the substitution rate based on the system out NOx value, adjust the ammonia to NOx ratio based on the space velocity, the ammonia to NOx ratio, the exhaust temperature, the substitution rate, the conversion efficiency target, and the conversion efficiency differential, and determine a diesel exhaust fluid dosing rate for the diesel exhaust fluid dosing unit.

A method of detecting a need for regeneration of an exhaust particulate filter is described. A first pressure drop is detected in a flow section of an exhaust system which includes the exhaust particulate filter. In addition, an exhaust gas temperature is determined. An exhaust gas mass flow flowing through the exhaust particulate filter is then calculated on the basis of the exhaust gas temperature and the pressure drop. Furthermore, a second pressure drop at the exhaust particulate filter is determined. A need for regeneration is detected when the second pressure drop exceeds a predefined pressure limit value that is dependent on the exhaust gas mass flow. Moreover, an exhaust system for an internal combustion engine is presented which includes an exhaust particulate filter.

The present invention relates generally to the field of exhaust treatment systems for purifying exhaust gas discharged from a lean burn engine. The exhaust treatment system comprises a Diesel Oxidation Catalyst (DOC), a Catalyzed Soot Filter (CSF), a reductant injector, an AEI zeolite based Selective Catalyzed Reduction (SCR) catalyst and an Ammonia Oxidation Catalyst (AMOX) downstream to the AEI zeolite based SCR catalyst.

A hybrid vehicle comprises an engine, an energy storage device, and an aftertreatment system comprising a SCR catalyst configured to treat constituents of an exhaust gas. A controller is operatively coupled to the engine, the energy storage device, and the after treatment system, and configured to estimate an exhaust gas temperature and flow rate of the exhaust gas based on a set of engine operating parameters. The controller determines an exhaust gas cooling rate based on the exhaust gas temperature, flow rate, and a SCR catalyst temperature, and an ambient cooling rate based on an ambient temperature, a vehicle speed and the catalyst temperature. The controller determines a SCR catalyst temperature change rate based on the exhaust gas and ambient cooling rates, and adjusts a load distribution between the engine and the energy storage device based on the SCR catalyst temperature change rate.

An exhaust gas system for an internal combustion engine includes at least one component which delimits an exhaust gas flow volume via an outer wall and, on an inner side of the outer wall which faces the exhaust gas flow volume, supports at least one shielding element. An intermediate space is formed between the outer wall and the shielding element. At least one connecting molding on the shielding element is directed toward the outer wall and is connected fixedly to the outer wall.

A method is disclosed for controlling an engine assembly comprising an internal combustion engine and an exhaust gas treatment apparatus. The aftertreatment assembly may require cleaning from time to time, and where this involves active thermal management of the aftertreatment assembly, the method involves performing the following steps: (a) imposing a first limit on engine speed; (b) awaiting an engine safe state; and (c) implementing a cleaning process comprising: (i) injecting fuel into the engine such that the fuel passes through the engine without combusting for the fuel to combust in the diesel oxidation catalyst so as to target an increase in exhaust gas temperature in the diesel oxidation catalyst; and (ii) removing the first limit on engine speed and targeting an engine speed set point, wherein the engine speed set point is at a higher speed than the first limit on engine speed.

A method includes: interpreting first oxygen data acquired by a first nitrous oxide (NOx) sensor indicative of a first amount of oxygen in an exhaust flow at a location in or proximate to an exhaust aftertreatment system, wherein the exhaust aftertreatment system is in exhaust gas receiving communication with an engine; estimating an amount of oxygen in the exhaust flow entering the exhaust aftertreatment system from the engine based on engine operation data; and, determining that the NOx sensor is faulty based on determining that a difference between the first amount of oxygen and the estimated amount of oxygen is greater than a threshold value.