A method of calculating an ammonia (NH3) mass generated in a lean NOx trap (LNT) of an exhaust purification device includes sequentially calculating a NH3 mass flow at a downstream of each slice from a first slice to an n-th slice, and integrating the NH3 mass flow at the downstream of the n-th slice over a predetermined time, wherein the calculation of the NH3 mass flow at the downstream of the i-th slice comprises calculating a NH3 mass flow flowing into the i-th slice, calculating a NH3 mass flow generated at the i-th slice, and adding the NH3 mass flow generated at the i-th slice to a value obtained by subtracting the NH3 mass flow used to reduce the NOx and the O2 at the i-th slice from the NH3 mass flow flowing into the i-th slice.

In a control apparatus for an internal combustion engine in which processing of regenerating the NOx storage capacity of an NSR catalyst is carried out in accompany with processing of diagnosing an abnormality in an exhaust gas purification device including the NSR catalyst, the present invention is intended to suppress the fluctuation of torque at the time of regenerating the NOx storage capacity of the NSR catalyst, and to terminate abnormality diagnostic processing quickly. According to the invention, by setting an engine air fuel ratio, which has been set to a lean air fuel ratio before the processing of regenerating the NOx storage capacity of the NSR catalyst is started, to a weak lean air fuel ratio which is lower than a basic lean air fuel ratio and higher than a stoichiometric air fuel ratio, it becomes possible to suppress the fluctuation of torque at the time of regeneration processing being started, and to terminate abnormality diagnostic processing at an early period of time.

A method of regenerating a lean NOx trap (LNT) of an exhaust purification system provided with the LNT and a selective catalytic reduction (SCR) catalyst may include: determining whether a regeneration release condition of the LNT is satisfied; determining whether a regeneration demand condition of the LNT is satisfied; and performing regeneration of the LNT if the regeneration release condition of the LNT and the regeneration demand condition of the LNT are satisfied. In particular, the regeneration release condition of the LNT is satisfied if all of an engine operating condition, an LNT state condition, and a lambda sensor synchronization condition are satisfied.

A method for controlling regeneration a catalyst by an exhaust gas purification device includes: measuring a temperature of exhaust gas flowing into a first catalyst unit; estimating a NO.sub.x amount loaded into the first catalyst unit and a slip amount of NO.sub.x of the first catalyst unit by using the temperature and an amount of the exhaust gas of the first catalyst unit; calculating a temperature of a second catalyst unit by using the temperature of the first catalyst unit; and estimating a NO.sub.x amount flowing into the second catalyst unit by using at least one of the slip amount of NO.sub.x of the first catalyst unit and the temperature of the second catalyst unit.

Systems, apparatuses, and methods include an upstream exhaust analysis circuit structured to determine a characteristic of an exhaust gas stream entering a nitrous oxide (NOx) storage catalyst; a prediction circuit structured to predict a downstream NOx concentration of an exhaust gas stream exiting the NOx storage catalyst based on a model of a NOx storage capacity or a dynamic response of the NOx storage catalyst; a downstream exhaust analysis circuit structured to determine a downstream NOx concentration of the exhaust gas stream exiting the NOx storage catalyst; and a comparison circuit structured to compare the predicted downstream NOx concentration to the determined downstream NOx concentration, and determine a health of the NOx storage catalyst based on the comparison.

In a process for adapting an amount of reducing agent for a removal of nitrogen oxides from the gases in an exhaust line, a first alignment of the amounts of nitrogen oxides measured by upstream and downstream sensors is performed without injection of agent and with a catalyst of the system emptied of ammonia. A second alignment of the estimated reduction of nitrogen oxides with the measured reduction is performed by a difference between amounts of nitrogen oxides upstream and downstream during a substoichiometric injection of reducing agent without creating a store of ammonia in a catalyst of the system with a first correction of the amount of agent. A third alignment of an estimated efficiency of retaining nitrogen oxides with a efficiency measured by the sensors is performed, this third alignment taking place via a second correction of the amount of reducing agent injected as an adaptive correction.

An after treatment method is disclosed. The after treatment method may include: operating an engine at a lean air/fuel ratio; calculating an amount of NH.sub.3 stored in an SCR catalyst; calculating an amount of NOx which will flow into the SCR catalyst; determining whether conversion to a rich air/fuel ratio is desired; calculating, when the conversion to the rich air/fuel ratio is desired, a rich duration for which the rich air/fuel ratio is maintained and a target air/fuel ratio; and operating the engine at the target air/fuel ratio for the rich duration.

The present invention provides a fuel supply system, for an eco-friendly ship, which selectively uses an existing fuel and an ammonia fuel or uses a mixture thereof as a fuel for a propulsion engine and a power generation engine of a ship so as to follow ship greenhouse gas regulations to be reinforced in phases at major points until 2050.

A method for operating an engine system that includes an internal combustion engine and an exhaust aftertreatment device. The method includes: carrying out a filling control in order to regulate a filling level of the exhaust aftertreatment device as a function of a predefined filling level setpoint value, a lambda setpoint value for a lambda regulation being predefined as a manipulated variable, adapting the filling control with the aid of an adaptation variable that indicates a correction value for the lambda setpoint value, and storing an adaptation value as a function of an operating range of the engine system, the adaptation value in question being updated with the value of the adaptation variable for the instantaneous operating range.

A method for operating an exhaust-gas burner (B) of a vehicle (100) which has at least an internal combustion engine (V) and a catalytic converter (C1, C2), wherein exhaust gases (22, 24) of the exhaust-gas burner (B) are merged, upstream of the catalytic converter (C1, C2), with exhaust gases (12) of the internal combustion engine (V), forming an exhaust-gas mixture, wherein a lambda value of the exhaust gases (22, 24) of the exhaust-gas burner (B) is set in a manner dependent on a lambda value of the exhaust gases (12) of the internal combustion engine (V).