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.

A reductant dosing system includes: a doser; a fixed displacement pump in fluid communication with the doser; a reductant source in fluid communication with the fixed displacement pump; and a controller communicatively coupled to the fixed displacement pump to control operation of the fixed displacement pump, wherein the controller is programmed to operate the fixed displacement pump using a pressure control system responsive to data indicative of the doser not dosing reductant and the controller is programmed to operate the fixed displacement pump using a flow control system responsive to data indicative of the doser dosing reductant.

Embodiments described herein methods can be used in particulate filter regeneration, such as particulate filters used for filtering the exhaust of an engine, e.g., a diesel engine. Systems herein can be configured to dispense combustion gas(es) into housing were a particulate filter is contained and to ignite the combustion gases. Methods for conducting a safety verification process of such systems are disclosed, as well as methods for regenerating the filters. Still other embodiments are described.

The invention concerns a method (200) of detecting an emulator for an SCR catalytic converter system (10) with the following steps: operating the SCR catalytic converter system (10) in a test state; and measuring a test variable of the SCR catalytic converter system (10); and deciding whether the test variable is behaving as for an SCR catalytic converter system (10) with or without an emulator.

A reductant insertion assembly comprises a reductant bladder defining a bladder internal volume for holding a reductant. The reductant bladder comprises a bladder inlet and a bladder outlet. A pressure sensor is positioned downstream of the bladder outlet. The pressure sensor is operable to sense a pressure of the reductant downstream of the reductant bladder, and generate a pressure signal indicative of the pressure. A compression mechanism is operably coupled to the reductant bladder. The compression mechanism is configured to selectively exert a compressive force on the reductant bladder so as to expel the reductant therefrom via the bladder outlet. The compression mechanism exerts the compressive force in response to the pressure signal.

The present invention discloses methods and devices for controlling a heated mixer, situated downstream of a Urea-Water Solution (UWS) injector, to reduce NOx emission in an exhaust system from combustion engines, wherein the exhaust system has a Selective Catalytic Reduction (SCR) catalyst situated downstream of the UWS injector and the heated mixer, Methods include: determining a NOx reduction efficiency of the SCR catalyst; evaluating at least one reductant Uniformity Index (UI) based on operating parameters of the exhaust system and a mixer power calculation map; and modifying a mixer temperature of the heated mixer by regulating power to the heated mixer based on at least one reductant UI in order to improve at least one reductant UI and/or improve the NOx reduction efficiency. Alternatively, the method further includes: detecting at least one potential improvement of at least one UI and/or the NOx reduction efficiency based on an increased ammonia mass.

A method of detecting a blocked pressure line in an internal combustion engine SCR system, which includes a feed pump, a dosing module, a pressure sensor, and an electronic control unit, includes a reference signal of a pressure (p) in the pressure line being measured over a measuring time (t.sub.M) if a reducing agent solution is not dosed by the dosing module, and a signal energy of the reference signal is then calculated; a pressure signal being measured over the measuring time (t.sub.M) during the dosing of a dosing mass of the reducing agent solution by the dosing module; and a signal energy of the pressure signal is then calculated; a ratio of the signal energies of the pressure signal to the signal energy of the reference signal being calculated; and finally the blocked pressure line being detected if the ratio falls short of a first pre-definable threshold value.

This delivery module includes: a pump for making the liquid flow; and an electronic circuit for controlling the pump. The delivery module further includes a channeling block having two channeling elements which define, when they are superimposed, channels for the liquid and which include: an inlet channel and an outlet channel.

A method and device for controlling a delivery device for an aqueous urea solution in a motor vehicle, with a tank, with a suction line, with a pump, with a pressure line, and with an injector, wherein the aqueous urea solution can be conveyed from the tank along the suction line, through the pump, through the pressure line, and to the injector. The method performs a rinsing procedure of at least the pressure line, wherein the pump is operated counter to its usual conveying direction during the rinsing procedure and the injector is closed in a first phase of the method, wherein the pump is operated for an operating duration t1 and at a speed of rotation n1 during the first phase of the method.

A method for operating a device for dosed supply of a liquid, having a pump to deliver the liquid. The pump has an inlet and an outlet. An eccentric is arranged on the pump housing and a deformable diaphragm is arranged between a pump housing and the eccentric. The deformable diaphragm and the pump housing delimit a delivery path from the inlet to the outlet. The seal can be displaced along the delivery path by movement of the eccentric. A pressure sensor is connected to the outlet of the pump. A liquid is delivered by the pump. A time curve of the pressure at the outlet of the pump is monitored during delivery by the at least one pressure sensor. An angle position of the eccentric of the pump is detected using at least one characteristic feature of the time curve at the outlet.