A method for controlling the operation of an exhaust aftertreatment system (EATS) in a vehicle is described. The EATS comprises a main SCR catalyst and a pre-SCR catalyst, a pre-injector arranged upstream the pre-SCR catalyst for providing reductant, a bypass channel fluidly connected to the fluid channel and arranged to bypass the pre-SCR-catalyst and the pre-injector, and a valve configured to control a split of exhaust gases between the pre-SCR catalyst and the bypass channel. The method includes determining the amount of ammonia stored in the pre-SCR catalyst; determining the temperature of the main SCR catalyst; when the ammonia storage in the pre-SCR catalyst is below an ammonia storage threshold and the temperature of the main SCR catalyst is above a temperature threshold, injecting reductant by the pre-injector and controlling the valve to allow a flow of exhaust gases to the pre-SCR catalyst sufficient for transporting the injected reductant to the pre-SCR catalyst for increasing the ammonia storage.

An aftertreatment system comprises a SCR system, an engine out NOx (EONOx) adjustment system and a controller. The controller is configured to instruct the EONOx adjustment system to adjust an EONOx amount between a high EONOx level for a first predetermined time and a low EONOx level for a second predetermined time when the SCR system is in a diagnostic enabling condition. The controller determines a SCR system out NOx (SONOx) amount. The controller determines an efficiency parameter of the SCR system from the SONOx amount when the EONOx amount transitions from the low EONOx level to the high EONOx level and if the efficiency parameter satisfies a predetermined threshold. In response to the efficiency parameter not satisfying the predetermined threshold, the controller determines that the SCR system has failed.

An arrangement for testing or treating a dosing valve of a dosing device of a dosing system in a vehicle includes connecting an electrical test drive to an electrical connector of the dosing device and connecting a dosing tester to a liquid inlet of the dosing device. Thereafter, an outlet valve of the dosing tester is opened to provide liquid under pressure to a liquid inlet of the dosing device. After a first given time, the electrical test drive provides pulses to repeatedly attempt to open the dosing valve. Upon a reduction in liquid level of liquid within the dosing tester in response to opening of the dosing valve, an operator closes the outlet valve of the dosing tester to discontinue the treatment.

Operating an engine exhaust aftertreatment system includes receiving fluid pressure data of a reductant pump, determining a pump operating state, and comparing a pump health parameter to a prognostic pump failure criterion based upon the determining a pump operating state. Operating an engine exhaust aftertreatment system further includes outputting a pump health alert based upon a difference between the pump health parameter and the prognostic pump failure criterion. Related control logic is also disclosed.

An exhaust gas purification device (26) for a gas turbine engine (10) comprises a catalyst chamber (64, 96) defined in an exhaust gas passage (22), a reduction agent container (32) containing a solid material that releases a reduction agent gas effective for NOx reduction when heated, a heating device (36, 38) for heating the solid material contained in the reduction agent container, and a reduction agent gas supply passage (48) for supplying the reduction agent gas released from the solid material into the catalyst chamber.

Systems and apparatuses include an engine, an aftertreatment system including a catalyst, and a controller coupled to the aftertreatment system and the engine. During a warmup period for an engine, the controller determines a value regarding a mass flow rate of exhaust gas based on information received from at least one of the engine or the aftertreatment system. The controller receives a target value regarding the mass flow rate of the exhaust gas. The controller controls at least one of the engine, the aftertreatment system, or at least one component associated therewith to reach or attempt to reach the target value regarding the mass flow rate of the exhaust gas.

Systems and methods for controlling a gasoline urea selective catalytic reductant catalyst are described. In one example, an observer is provided that corrects an estimate of an amount of NH.sub.3 that is stored in a SCR. The amount of NH.sub.3 that is stored in the SCR is a basis for generating additional NH.sub.3 or ceasing generation of NH.sub.3.

Systems and methods are disclosed for determining or diagnosing a reagent dosing system failure to provide sufficient reagent to an exhaust aftertreatment system that includes an SCR catalyst to satisfy a reagent dosing command.

A method is provided for operating a vehicle, in particular a watercraft, with at least one combustion engine that emits pollutants contained in an exhaust gas or wastewater. The current position of the vehicle is determined by a location determination. A closed-loop and/or open-loop control device is provided which sets or adjusts the quantity of at least one pollutant emitted by the combustion engine in a self-acting manner or automatically, in accordance with the determined position of the vehicle and with information on local pollutant regulations, in particular exhaust and/or water regulations.

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.