Provided is a catalyst article for simultaneously remediating the nitrogen oxides (NOx), particulate matter, and gaseous hydrocarbons present in diesel engine exhaust streams. The catalyst article has a soot filter coated with a material effective in the Selective Catalytic Reduction (SCR) of NOx by a reductant, e.g., ammonia.

Methods and systems are provided for adjusting engine operating parameters in response to an emission output from vehicles within a region. In one example, a method comprises adjusting engine operating parameters in a portion of the vehicles to decrease an emission output therefrom.

An exhaust gas treatment system for an internal combustion engine includes an exhaust gas pathway configured to receive exhaust gas from the internal combustion engine and a non-thermal plasma generator positioned in the exhaust gas pathway. The non-thermal plasma generator is configured to increase a proportion of nitrogen dioxide in the exhaust gas. The system also includes a first treatment element positioned in the exhaust gas pathway downstream of the non-thermal plasma generator and a second treatment element positioned in the exhaust gas pathway downstream of the first treatment element. At least one of the first treatment element or the second treatment element includes a combined selective catalytic reduction and diesel particulate filter (SCR+F) element.

An exhaust treatment system arranged for treatment of an exhaust stream is presented. The exhaust treatment system comprises a first reduction catalyst device arranged for reduction of nitrogen oxides in said exhaust stream through the use of compounds comprising one or several of carbon monoxide and hydrocarbons, which are comprised in said exhaust stream when said exhaust stream reaches said first reduction catalyst device; a particulate filter which is arranged downstream of said first reduction catalyst device to catch and oxidize soot particles in said exhaust stream; a second dosage device arranged downstream of said particulate filter and arranged to supply an additive comprising ammonia or a substance from which ammonia may be extracted and/or released into said exhaust stream; and a second reduction catalyst device, arranged downstream of said second dosage device and arranged for reduction of nitrogen oxides in said exhaust stream through the use of said additive.

Methods and systems are provided for adjusting engine operating parameters in response to an emission output from vehicles within a region. In one example, a method comprises adjusting engine operating parameters in a portion of the vehicles to decrease an emission output therefrom.

An exhaust treatment system and method for the treatment of an exhaust stream from a combustion engine are provided. A first oxidation of compounds comprising one or more of nitrogen, carbon and hydrogen in the exhaust stream is carried out by a first oxidation catalyst. Further, a value (NO2_1/NOx_1)det for a ratio between a first amount of nitrogen dioxide and a first amount of nitrogen oxides leaving said first oxidation catalyst is determined. Active control of at least one parameter related to the combustion engine is carried out, based on the determined value, so that the ratio is impacted. A first additive is supplied into the exhaust stream, following which a first reduction of the first amount of nitrogen oxides is carried out through a catalytic reaction in a catalytic filter, which consists of a particulate filter with an at least partly catalytic coating with reduction characteristics. The catalytic filter is arranged for catching and oxidizing of soot particles, and to carry out the first reduction of the first amount of nitrogen oxides using the first additive.

Method and system for the removal of nitrogen oxides, volatile organic compounds and particulate matter from engine exhaust gasat cold start conditions.

An exhaust gas treatment system for an internal combustion engine includes an exhaust gas pathway configured to receive exhaust gas from the internal combustion engine and a non-thermal plasma generator positioned in the exhaust gas pathway. The non-thermal plasma generator is configured to increase a proportion of nitrogen dioxide in the exhaust gas. The system also includes a first treatment element positioned in the exhaust gas pathway downstream of the non-thermal plasma generator and a second treatment element positioned in the exhaust gas pathway downstream of the first treatment element. At least one of the first treatment element or the second treatment element includes a combined selective catalytic reduction and diesel particulate filter (SCR+F) element.

Systems are provided for a diesel oxidation catalyst. In one example, the diesel oxidation catalyst comprises a washcoat with different catalytically active portions for reacting with one or more of carbon containing compounds and NO.sub.x. The diesel oxidation catalyst is located upstream of a particulate filter in an exhaust passage.

A filter regeneration system for an internal combustion engine, the filter regeneration system including: a calculation unit configured to calculate a minimum oxygen concentration and a minimum nitrogen dioxide concentration at which a passive regeneration reaction, in which carbon in PM accumulated on a filter arranged in an exhaust gas passage of the internal combustion engine reacts with nitrogen dioxide and oxygen to generate carbon dioxide and nitrogen monoxide, occurs based on an amount of the PM accumulated on the filter; and an exhaust gas temperature control unit configured to, in a case where an oxygen concentration and a nitrogen dioxide concentration in exhaust gas on an upstream of the filter are equal to or higher than the minimum oxygen concentration and the minimum nitrogen dioxide concentration, respectively, control a temperature of exhaust gas flowing into the filter within a temperature range in which the passive regeneration reaction occurs preferentially.