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.

An aftertreatment system includes an inlet exhaust section, an outlet exhaust section, a first aftertreatment component, a first dosing module, and a second dosing module. The inlet exhaust section receives exhaust. The outlet exhaust section is in fluid communication with the inlet exhaust section. The first aftertreatment component receives the exhaust from the inlet exhaust section, treats the exhaust, and provides the exhaust to the outlet exhaust section. The first dosing module is positioned along the inlet exhaust section. The first dosing module is structured to selectively dose the exhaust with reductant. The second dosing module is positioned along the outlet exhaust section. The second dosing module is structured to selectively dose the exhaust with the reductant.

Technical solutions described herein include an emissions control system for treating exhaust gas in a motor vehicle including an internal combustion engine. The emissions control system includes a model-based controller to control reductant injections into the exhaust gas. Controlling the reductant injections includes determining an amount of NOx and an amount of NH3 at an outlet of the first SCR device, and at an outlet of the second SCR device. The controlling further includes computing an amount of reductants to inject to maintain a first predetermined ratio between the amount of NH3 and the amount of NOx at the outlet of the first SCR device and to maintain a second predetermined ratio between the amount of NH3 and the amount of NOx at the outlet of the second SCR device. Further, the controlling includes sending a command for receipt by the reductant injectors to inject the computed amount of reductants.

Technical solutions described herein include an emissions control system for treating exhaust gas in a motor vehicle including an internal combustion engine. The emissions control system includes a model-based controller to control reductant injections into the exhaust gas. Controlling the reductant injections includes determining an amount of NOx and an amount of NH3 at an outlet of the first SCR device, and at an outlet of the second SCR device. The controlling further includes computing an amount of reductants to inject to maintain a first predetermined ratio between the amount of NH3 and the amount of NOx at the outlet of the first SCR device and to maintain a second predetermined ratio between the amount of NH3 and the amount of NOx at the outlet of the second SCR device. Further, the controlling includes sending a command for receipt by the reductant injectors to inject the computed amount of reductants.

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.

An automotive exhaust aftertreatment system for reducing effluents, such as nitrous oxides (NOx), in exhaust gasses passing through the system. The automotive exhaust aftertreatment system includes a doser, an active heating element, and a controller coupled to the doser and the active heating element. The doser is configured to feed a reducing agent into an exhaust stream moving through the exhaust aftertreatment system. The active heating element configured to produce heat from electrical energy and heat passageways that carry the reducing agent through the doser.

A diesel exhaust system includes multiple injectors for providing diesel exhaust fluid to an exhaust to reduce NO.sub.x emissions. Two or more injectors provide DEF to the exhaust system of an engine. In one mode, the injectors alternately inject DEF fluid. In one embodiment, the system includes a NO.sub.x sensor or a NO.sub.x model to assist in determining an amount of DEF that must be provided. In a high DEF output operating mode, the DEF amount for one injector is output at a higher rate than the other injector such that deposits may form. After the injector at the higher rate of injection operates for a selected fraction of time, the other injector provides DEF fluid at the higher rate. Further, the system calculates an estimated developed liquid film mass for each injector output. When the estimated developed liquid film mass is not less than a parameter limit film mass, the system performs ATS regeneration.

The present invention shows a combustion engine comprising an exhaust gas aftertreatment system having at least one injector for injecting a reductant into an exhaust gas passage, and an emergency stop that cuts down the energy supply of the components of the engine upon activation, wherein the combustion engine comprises an injector extraction system that extracts the injector from the exhaust gas passage when the emergency stop is activated.

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.

An internal combustion engine exhaust purification device includes a filter which is disposed in an exhaust path and collects particulate matter in exhaust gas, an injection valve which is disposed upstream of the filter in the exhaust path and injects fuel into the exhaust path, a fuel pump which supplies a fuel to the injection valve, a shut-off valve which is interposed between the fuel pump and the injection valve, and selectively shuts off a fuel supply from the fuel pump to the injection valve, and a control unit which controls the injection valve and the shut-off valve. The control unit closes the shut-off valve when the control unit detects an opened adherence failure of the injection valve and detects an abnormal temperature rise of the filter during regeneration of the filter.