The present invention relates to a method for adaption of an exhaust treatment system arranged for treating an exhaust stream produced by an engine, where the exhaust treatment system includes at least a first additive dosage device, a first selective catalytic reduction catalyst arranged downstream of the first additive dosage device, a second additive dosage device arranged downstream of the first selective catalytic reduction catalyst, and a second selective catalytic reduction catalyst arranged downstream of the second additive dosage device. The method includes initiating an adaption of the second selective catalytic reduction catalyst, and controlling, during the adaption of the second selective catalytic reduction catalyst, the first additive dosage device to inject additive in accordance with at least one injection rule being designed for the adaption.

A method for diagnosing NOx sensors in an exhaust aftertreatment system includes suspending reductant dosing in an exhaust aftertreatment system; purging a reductant deposit in a selective catalytic reduction (SCR) system of the exhaust aftertreatment system; adjusting at least one of an ignition timing and an engine speed for an engine to adjust an engine out nitrogen oxide (NOx) amount; receiving measured SCR inlet NOx data from a SCR inlet NOx sensor and measured SCR outlet NOx data from a SCR outlet NOx sensor; determining a phase shift between the measured SCR inlet and SCR outlet NOx data; applying the determined phase shift to the SCR outlet NOx data; and determining a diagnostic feature based on the SCR inlet NOx data and the phase shifted SCR outlet NOx data regarding a state of the SCR inlet and outlet NOx sensors.

Method for operating an internal combustion engine which has a gas combustion system and an exhaust gas post-treatment system. Exhaust gas that leaves the gas combustion system is directed to at least one CH4 oxidation catalytic converter of the exhaust gas post-treatment system. The CH4/NO2 mole ratio in the exhaust gas is set in a defined fashion by at least one gas-combustion-system-side and/or exhaust-gas-post-treatment-system-side measure upstream of at least one CH4 oxidation catalytic converter.

A method to control an internal combustion engine provided with an exhaust system for the exhaust gases of a vehicle having an exhaust duct and an exhaust gas after-treatment system comprising at least one catalytic converter arranged along the exhaust duct; a burner suited to introduce the exhaust gases into the exhaust duct to speed up the heating of said at least one catalytic converter, wherein a combustion chamber is defined inside the burner which receives fuel from an injector, designed to inject the fuel inside the combustion chamber and the fresh air by means of an air feeding circuit provided with a pumping device that feeds the air, a shut-off valve arranged upstream of the burner and a mass air flow sensor interposed between the pumping device and the shut-off valve; the method provides the following steps: calculating the thermal power required to reach the nominal operating temperature of said at least one catalytic converter; determining the objective air flow rate to be fed to the burner to obtain said thermal power required to reach the nominal operating temperature of said at least one catalytic converter; determining the nominal number of revolutions with which to operate the pumping device by means of a map depending on the objective air flow rate, on the ambient pressure, on the ambient temperature and on the pressure of the air entering the burner; determining a closed-loop contribution of the number of revolutions with which to operate the pumping device by means of a PID controller which tries to zero a difference between the objective air flow rate and the air flow rate detected by the mass air flow sensor; determining a further contribution of the number of revolutions with which to operate the pumping device depending on the integral action of the PID controller under stationary conditions; and determining the actual number of revolutions with which to operate the pumping device by the sum of the nominal number of revolutions, the closed-loop contribution of the number of revolutions with which to operate the pumping device and the further contribution of the number of revolutions with which to operate the pumping device.

A method to control an internal combustion engine having an exhaust duct and an exhaust gas after-treatment system comprising at least one catalytic converter arranged along the exhaust duct; an oxygen sensor housed along the exhaust duct and arranged upstream of said at least one catalytic converter; and a burner suited to introduce the exhaust gases into the exhaust duct upstream of the oxygen sensor the method provides the steps of identifying the operation phases in which the internal combustion engine is turned off and the burner is turned on so that the oxygen sensor is exclusively hit by the exhaust gases produced by the burner; acquiring the signal generated by the oxygen sensor; and using the signal generated by the oxygen sensor to determine the objective fuel flow rate and the objective air flow rate to be fed to the burner.

A method includes calculating whether a quantity of the PMs accumulated in a PF is at or above a risk level at which damage to the PF is caused when reproducing the PF, calculating a driving condition index by accumulating a weighting factor for a driving condition under which there is a likelihood of causing the damage to the PF, when the amount of accumulated PMs is at or above the risk level; calculating a temperature index in accordance with a temperature of the PF and a PM index in accordance with the quantity of the accumulated PMs when the quantity of the accumulated PMs is at or above the risk level; calculating a degradation condition index considering the driving condition index, the temperature of the PF, and the quantity of accumulated PMs; and changing a reproduction periodicity of the PF according to the degradation condition index.

A method for monitoring emissions in the exhaust gas of an internal combustion engine in a vehicle, comprising carrying out (520) multiple successive emission measurements for at least one component in the exhaust gas, wherein each of the emission measurements is respectively performed after a driving distance of predefined length is covered by the vehicle; storing (540) a distance-related emission value (E.sub.i), which was obtained (530) on the basis of the measurement, in a memory element (42, 200, 400) for each of the emission measurements; and forming (550) a smoothed emission level for a current point in time on the basis of multiple of the previously stored distance-related emission values, wherein more recent emission values are taken into consideration more strongly than emission values lying farther back in time in the formation of the smoothed emission level.

A method for controlling exhaust flow in an EATS of a vehicle. A NO.sub.x sensor output parameter is monitored. It is determined that the NO.sub.x sensor output parameter is below a limit. When the NO.sub.x sensor output parameter is below the limit, it is determined that a first part of the exhaust flow should bypass at least a first area of the SCR unit and that a second part of the exhaust flow should be inputted to at least the first area of the SCR unit. It is initiated that the first part is bypassed and that the second part is inputted to at least the first area of the SCR unit. An amount of reductant that should be added to the second part of the exhaust flow is determined. Addition of the amount of reductant is initiated.

Methods and systems are provided for model-based determination of a temperature distribution of an exhaust aftertreatment system of a vehicle. A power demand from a first component of the aftertreatment system is measure, a heat transfer into the first component of the aftertreatment system based on power demand of the first component and a configurable emissivity value of the exhaust gas is determined, and the temperature of the first component based on the calculated heat transfer is calculated.

A method for controlling urea injection in an exhaust aftertreatment system includes injecting urea at a flow rate upstream of the first catalytic reduction device; measuring a level of nitrogen oxides downstream of the first catalytic reduction device and upstream of the second catalytic reduction device; controlling the flow rate of the urea injection until the measured level of nitrogen oxides fulfils a predetermined condition; if the measured level of nitrogen oxides is decreasing in response to reducing the flow rate of the urea injection, reducing the flow rate of the urea injection, and controlling a flow rate of urea injection using the second urea injector upstream of the second catalytic reduction device according to the measured level of nitrogen oxides downstream of the first catalytic reduction device and upstream of the second catalytic reduction device.