A method for controlling exhaust flow in an EATS of a vehicle. A NO.sub.x sensor output parameter is monitored. It is determined that the NO.sub.x sensor output parameter is below a limit. When the NO.sub.x sensor output parameter is below the limit, it is determined that a first part of the exhaust flow should bypass at least a first area of the SCR unit and that a second part of the exhaust flow should be inputted to at least the first area of the SCR unit. It is initiated that the first part is bypassed and that the second part is inputted to at least the first area of the SCR unit. An amount of reductant that should be added to the second part of the exhaust flow is determined. Addition of the amount of reductant is initiated.

A valve device for an exhaust flow passage includes a toggle mechanism, in which a support-side link member and a valve-side link member form a first stopper mechanism and a second stopper mechanism. The first stopper mechanism is configured to limit a link angle formed by the support-side link member and the valve-side link member by abutment of a first support-side stopper portion formed in the support-side link member and a first valve-side stopper portion formed in the valve-side link member against each other. The second stopper mechanism is configured to limit the link angle by abutment of a second support-side stopper portion formed in the support-side link member and a second valve-side stopper portion formed in the valve-side link member.

An exhaust after-treatment system for treating an exhaust produced by an engine. The exhaust after-treatment system includes an exhaust passage, at least one catalytic exhaust after-treatment component in communication with the exhaust passage for treating the exhaust, and a water-removal device in communication with the exhaust passage that receives a portion of the exhaust therein at a location positioned upstream from the catalytic exhaust after-treatment component. The water-removal device is defined by a housing that includes a water-removal membrane that separates water from the portion of the exhaust to provide a permeate that is enriched with water, and to produce a retentate that is water depleted that facilitates the treating of the exhaust by the catalytic exhaust after-treatment component.

A method for operating an exhaust gas aftertreatment system, having the following steps: determining a permissible energy input into at least one exhaust gas aftertreatment element of the exhaust gas aftertreatment system; ascertaining a current energy input into the at least one exhaust gas aftertreatment element by ascertaining at least one energy input variable which characterizes the current energy input; and actuating an adjusting device which varies a distribution of an exhaust gas mass flow to the at least one exhaust gas aftertreatment element and a bypass path that runs about the at least one exhaust gas aftertreatment element depending on the permissible energy input and the current energy input.

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.