Subject of the invention is an exhaust gas purification system for a gasoline engine, comprising in consecutive order the following devices: a first three-way-catalyst (TWC1), a gasoline particulate filter (GPF) and a second three-way-catalyst (TWC2), wherein the oxygen storage capacity (OSC) of the TWC2 is greater than the OSC of the GPF, wherein the OSC is determined in mg/l of the volume of the device.

The invention also relates to methods in which the system is used and uses of the system.

The present invention provides an exhaust purification filter with which pressure loss can be reduced, the filter having high exhaust purification performance and granular-substance-filtering performance. The exhaust purification filter comprises a filter base material having a wall flow structure, and an exhaust purification catalyst supported on a dividing wall of the filter base material, the exhaust purification filter being such that: a median pore diameter (D50) of the filter base material according to a volumetric basis is 15 μm or greater; and the exhaust purification catalyst is unevenly supported on a high-density layer, in which the density of the exhaust purification catalyst is relatively high, and a low-density layer, in which the density of the exhaust purification catalyst is relatively low.

Certain selective catalytic reduction (SCR) articles, systems and methods provide for high NOx conversion while at the same time low N.sub.2O formation. The articles, systems and methods are suitable for instance for the treatment of exhaust gas of diesel engines. Certain articles have zoned coatings disposed thereon, for example, a zoned coating comprising an upstream zone comprising a coating layer comprising a steam-activated iron-containing molecular sieve and a downstream zone comprising a coating layer comprising a high copper-containing molecular sieve.

Methods and/or systems for operating an exhaust-gas aftertreatment system of an internal combustion engine include: setting the internal combustion engine to a diagnostic operating mode with relevant diagnostic operating parameters of the internal combustion engine are set to correspond with diagnostic default values; inducing a targeted, defined NH.sub.3 and/or NO.sub.X concentration change upstream of the filter; measuring the NH.sub.3 and/or NO.sub.X concentration change downstream of the filter; providing a correlating concentration comparison value; evaluating the concentration change on the basis of the respective concentration comparison value and predefined limit values; and diagnosing the SCR particle filter as defective if the evaluation yields that the concentration comparison value has overshot a predefined limit value.

An engine exhaust aftertreatment device includes a first exhaust treatment unit and/or a second exhaust treatment unit; the first exhaust treatment unit includes a first bypass pipeline and a first connection pipe provided between a DPF and an SCR; the second exhaust treatment unit comprises a second bypass pipeline and a second connection pipeline provided between a DOC and the DPF, one end of the second bypass pipeline being in communication with the turbine front exhaust pipe, and the other end of the second bypass pipeline being in communication with the second connection pipeline; when it is detected that an engine satisfies a starting condition of the first exhaust treatment unit, the first exhaust treatment unit starts; and when it is detected that the engine satisfies a starting condition of the second exhaust treatment unit, the second exhaust treatment unit starts.

An exhaust gas aftertreatment system includes a first sensor configured to measure a parameter and a second sensor disposed proximate the first sensor and configured to measure the parameter. The system includes a controller configured to initially utilize the first sensor as a primary sensor. At target intervals, the controller is configured to receive a first sensor value from the first sensor and receive a second sensor value from the second sensor. The controller is configured to calculate a difference between the first sensor value and the second sensor value and determine if the difference between the first sensor value and the second sensor value is greater than a threshold value. If the difference between the first and second sensor values is greater than the threshold value, the controller is configured to stop utilizing the first sensor as the primary sensor and utilize the second sensor as the primary sensor.

The invention relates in particular to a method for adjusting the loading (19) of a particulate filter (9) and to an assembly designed to carry out the method, wherein the exhaust gas aftertreatment unit (8) comprises at least two SCR systems (11, 12) and a particulate filter (9), a first operating material amount being introduced in a metered manner before the first SCR system (11), and a second operating material amount being introduced in a metered manner before the second SCR system (12), the operating material being convertible into a reducing agent. The state of loading of the particulate filter (9) is determined using a model, and, if the determined state of loading is below a previously defined loading range (16), the first operating material amount is adjusted in such a way that the amount of reducing agent is greater than or equal to the amount of reducing agent necessary for nitrogen oxide reduction in accordance with the reaction stoichiometry in the first SCR system (11), and/or, if the determined state of loading is above a previously defined loading range (16), the first operating material amount is adjusted in such a way that the amount of reducing agent is less than the amount of reducing agent necessary for nitrogen oxide reduction in accordance with the reaction stoichiometry in the first SCR system (11).

A method for controlling the operation of an engine system in a vehicle. The engine system including an engine and an exhaust aftertreatment system having an SCR catalyst and a DPF. The method includes determining preview information of the vehicle operation based at least on an upcoming road event and an engine operation associated with the upcoming road event; performing, in response of the preview information, at least one of: controlling the operation of the engine system by increasing reductant injection to meet an ammonia storage threshold level; controlling the operation of the engine system by increasing the engine out NOx to reduce the ammonia storage in the SCR catalyst to meet an ammonia slip threshold level in the SCR catalyst; controlling the operation of the engine system by decreasing the engine out NOx to increase the amount of engine out particles to meet a soot threshold level in the DPF.

The present invention relates to a selective catalytic reduction catalyst comprising a porous wall-flow filter substrate; wherein in the pores of the porous internal walls and on the surface of the porous internal walls, the catalyst comprises a selective catalytic reduction coating comprising a selective catalytic reduction component comprising a zeolitic material comprising one or more of copper and iron. The present invention further relates to a process for preparing a selective catalytic reduction catalyst using particles of a carbon-containing additive and an aqueous mixture comprising said particles of a carbon-containing additive.

A pivoting work vehicle includes an engine, an exhaust gas treatment apparatus, and a hood. The exhaust gas treatment apparatus is configured to treat exhaust gas from the engine. The hood is configured to cover the engine and the exhaust gas treatment apparatus. The exhaust gas treatment apparatus includes a DPF device and an SCR device. The exhaust gas is treated first by the DPF device, then by the SCR device. The DPF device and SCR device are each disposed so that the lengthwise directions thereof lie along the vertical direction. The DPF device and SCR device are arranged side-by-side in a direction orthogonal to the vertical direction.