A controller for a dosing module including a pump, an inlet manifold coupled to the pump, a nozzle, an outlet manifold coupled to the nozzle, a first branch coupled to the inlet manifold and the outlet manifold and having a first flow restrictor and a first valve, a second branch coupled to the inlet manifold and the outlet manifold and having a second flow restrictor and a second valve, and a sensor coupled to the inlet manifold and the outlet manifold, includes an input/output interface and a processing circuit. The input/output interface is configured to electronically communicate with the first valve and the second valve. The processing circuit configured to selectively cause the first valve to be in a first valve first position, in which the first valve facilitates fluid communication from the inlet manifold to the outlet manifold through the first branch, and a first valve second position.

The present invention relates to a method for diagnosing aftertreatment of exhaust gases resulting from combustion, wherein at least a first substance resulting from said combustion is reduced by supplying additive to an exhaust gas stream resulting from said combustion and use of a first reduction catalytic converter. The method includes: estimating an accumulated expected reduction of said first substance during a first period of time, determining an accumulated actual reduction of said first substance during a period of time at least substantially overlapping said first period of time, and generating a signal indicating a fault in said reduction of said first substance when said accumulated actual reduction differs from said accumulated expected reduction by a predetermined difference in occurrence of said first substance. The invention also relates to a corresponding system.

Disclosed is a process for the dynamic monitoring of the flow rate of liquid additive consumed by a liquid-additive injector of an exhaust gas treatment system of a motor vehicle. The measurement of the pressure of the liquid makes it possible firstly to deduce the flow rate circulating through the orifice and secondly, by knowing the operating characteristic of the pump, to determine the flow rate of liquid additive actually delivered to the system for treating polluting gases. The process also provides a phase of characterizing the pump, including commanding the closure of the injector, measuring at least two pressure values for two different operating speeds of the pump, and updating the pump operating characteristics table on the basis of the pressure values measured.

A method for controlling a return valve of an exhaust system and to an exhaust system with a control unit which is configured to carry out the method. The method is based on the object of avoiding an overpressure in the line system for urea solution as a result of a reduction in the injection rate. The method includes the steps of determining whether one or more of the following states are present during the operation of the exhaust system: a) an injection rate per unit of time of urea solution of the dosing valve is less than or equal to a predefined injection limit, b) a pressure measured by the pressure sensor in the line system overshoots a predefined first upper pressure limit (P2). The return valve is opened for a first predefined opening duration (Δt1) if states a) and b) are present and at least one of the states has already been present for at least a predefined period of time (Δta). The return valve is closed after the first predefined opening duration (Δt1) has elapsed.

The present disclosure provides a method of treating a diesel exhaust system that includes heating a reagent to a temperature such that at least a portion of the reagent is heated to a gaseous phase, injecting the reagent into a diesel exhaust stream upstream of a catalyst, and reacting the diesel exhaust with the heated reagent over the catalyst to convert NO.sub.x into N.sub.2 and H.sub.2O. The heating modulates a mass flow rate of the reagent by converting a state of matter of the reagent at least partially to the gaseous phase prior to or after being injected, and the heated reagent in the gaseous form reduces deposit formations within the diesel exhaust system.

In an assembly and methods for NO.sub.x reductant dosing with variable spray angle nozzle, according to various embodiments, a reductant dosage is calculated. A reductant delivery region in an exhaust stream area of an aftertreatment system and an actuation period may be specified. Based at least on the reductant delivery region and the actuation period, the reductant insertion assembly may be placed in a state for reductant delivery such that one of a first array of reductant insertion ports and a second array of reductant insertion ports is in an open position. The shape of the variable spray angle nozzle may define different levels. Different arrays of reductant delivery ports may have varying operating characteristics, such as diameter, number of ports, actuation time, and/or reagent delivery angle and may be activated based on reductant flow pressure and/or reductant flow velocity.

This degradation diagnosis device for an exhaust purification system makes it possible to discover degradation of a constituting component in an exhaust purification system at an early stage. The degradation diagnosis device for an exhaust purification system that purifies exhaust gas discharged from an internal combustion engine into an exhaust pipe is provided with: a degradation degree estimation unit that estimates the degree of degradation due to corrosion of a constituting component in the exhaust purification system based on the temperature of exhaust gas and the amount of a reducing agent injected into the exhaust pipe; a determination unit that determines whether the degradation degree estimated by the degradation degree estimation unit exceeds a predetermined threshold; and an output unit that outputs the result of determination made by the determination unit.

A method for controlling an SCR catalytic converter (20, 30), comprising detecting (200) concentration values (314, 324; 414, 424) in the exhaust gas downstream of the catalytic converter (20), wherein at least one concentration value for NH.sub.3 and one concentration value for NO.sub.x is detected; calculating (202) modeled concentration values (316, 322; 416, 422) for NH.sub.3 and NO.sub.x downstream of the catalytic converter on the basis of a catalytic converter model, wherein the model comprises an aging parameter (342, 442) which at least partially describes aging of the modeled catalytic converter; comparing (208) the detected concentration values with the modeled concentration values; and, in a manner dependent on the result of the comparison, changing the aging parameter (342, 442) of the model and/or changing a predefined dosing quantity for a reducing agent in the SCR catalytic converter.

The present disclosure relates to a system and a method for removing noxious gas from cleaning liquid discharged from an exhaust gas treatment apparatus and, more particularly, to a system and a method for removing noxious gas from cleaning liquid discharged from an exhaust gas treatment apparatus, which are capable of adjusting the discharge rate of the cleaning liquid in a noxious gas removal unit, which removes noxious gas remaining in a gaseous state in the cleaning liquid discharged from the exhaust gas treatment apparatus and discharges the cleaning liquid from which the noxious gas in the gaseous state has been removed, on the basis of a result of measurement of the level of the cleaning liquid in the noxious gas removal unit.

An aftertreatment system comprises a SCR system, a reductant injector operatively coupled to the SCR system, and a reductant insertion assembly operatively coupled to the reductant injector. The reductant insertion assembly comprises a pump configured to pump the reductant through the reductant injector. A controller is operatively coupled to the reductant insertion assembly and configured to receive predetermined calibration values of the pump corresponding to delivery of a reductant by the pump through a calibration injector. The controller determines a desired flow rate value of the reductant into the SCR system. The controller determines an insertion time of the reductant injector for delivering the reductant through the reductant injector based on the desired flow rate value, a pump operating parameter value of the pump and the predetermined calibration values, and activates the reductant injector for the insertion time.