A fluid delivery system for an exhaust aftertreatment system may include an outer housing, a pump, a filter assembly, an electric heating blanket, and a heater retention plate. The heater retention plate is shaped to correspond to the shapes of the pump and filter assembly. A lid of the outer housing contacts the heater retention plate and clamps the heating blanket between the heater retention plate and the pump and filter assembly so that the heating blanket takes the shapes of portions of the pump and filter assembly. The outer housing includes mounting flanges and reinforcement members extending from corresponding mounting flanges to corresponding sidewalls of the outer housing and forming a hollow space therebetween. The filter assembly includes compensation elements that contract in response to expansion of fluid within a pump housing due to freezing and expand in response to thawing of the fluid.

An object of the present disclosure is to provide an exhaust gas purification catalyst demonstrating superior storage of NOx contained in exhaust gas.

The exhaust gas purification catalyst of the present disclosure has a substrate, a first catalyst layer containing a catalytic metal for NOx reduction and a NOx storage material and formed on the substrate, and a second catalyst layer containing a catalytic metal for NOx oxidation and formed on the first catalyst layer. In the exhaust gas purification catalyst of the present disclosure, the value obtained by dividing the volume of all large pores having a pore volume of 1000 μm.sup.3 or more by the total volume of all medium pores of having a pore volume of 10 μm.sup.3 to 1000 μm.sup.3 in the second catalyst layer is 2.44 or less.

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, a first treatment element positioned within the exhaust gas pathway, a first injector configured to introduce a first reductant into the exhaust gas pathway upstream of the first treatment element, a second injector configured to introduce a second reductant into the exhaust gas pathway downstream of the first treatment element, a second treatment element positioned within the exhaust gas pathway downstream of the second injector, the second treatment element including a SCR element, and a controller configured to periodically initiate a desulfuring regeneration cycle by increasing a concentration of hydrocarbons in the exhaust gas and increasing the flow of the first reductant through the first injector to oxidize sulfur contamination in the first treatment element at temperatures between 400 and 500 degrees Celsius.

An exhaust gas purification apparatus for an internal combustion engine, capable of carrying out oxidation removal of PM deposited in a filter as a whole in an efficient manner, includes a filter arranged in an exhaust passage of the internal combustion engine and having an oxidation catalyst supported in at least an upstream side portion thereof, and a heating device arranged so as to be able to heat the upstream side portion of the filter irrespective of oxidation reaction heat of the oxidation catalyst, wherein when filter upstream regeneration processing to oxidize and remove deposition PM in the upstream side portion of the filter is carried out by controlling a heating device, an amount of decrease of the upstream side deposition PM by the filter upstream regeneration processing is reflected on an amount of filter PM deposition in the ordinary filter regeneration processing which oxidizes and removes the deposition PM in the entire filter by means of oxidation reaction heat of unburnt fuel generated by the oxidation catalyst supported in the filter, and the filter upstream regeneration processing is ended, even if the thus reflected amount of filter PM deposition is in a state of being larger than a reference amount of deposition which is a threshold value for ending the ordinary filter regeneration processing.

In an exhaust gas purification system provided with a denitration catalyst layer, a reducing agent oxidation catalyst layer is installed together; a reducing agent and air are supplied into the reducing agent oxidation catalyst layer at the time of catalyst regeneration of the denitration catalyst layer; a high-temperature oxidation reaction gas is produced by a reaction heat generated by an oxidation reaction of the reducing agent and the air in this reducing agent oxidation catalyst layer; and this high-temperature oxidation reaction gas is introduced into the denitration catalyst layer to heat the denitration catalyst, thereby recovering a denitration performance of the catalyst.

An exhaust purification system includes: a diesel oxidation catalyst (DOC) provided on an exhaust passage of an engine; a diesel particulate filter (DPF) provided on the exhaust passage at a position downstream of the DOC to collect particulate matter contained in exhaust gas; electrodes that detect a capacitance of the DOC; a particulate matter accumulation estimating unit that estimates an amount of particulate matter accumulated in the DPF on the basis of the detected capacitance; and a forced regeneration control unit that injects fuel into the DOC and performs forced regeneration that burns and removes at least the particulate matter accumulated in the DPF when the estimated accumulated particulate matter amount surpasses a predetermined amount.

Dosing and mixing exhaust gas includes directing exhaust gas towards a periphery of a mixing tube that is configured to direct the exhaust gas to flow around and through the mixing tube to effectively mix and dose exhaust gas within a relatively small area. Some mixing tubes include a slotted region and a non-slotted region. Some mixing tubes include a louvered region and a non-louvered region. Some mixing tubes are offset within a mixing region of a housing.

An oxidation catalyst device is placed so that a central axis of the oxidation catalyst device may be oriented along a right and left direction of a work vehicle; a reducing agent injection device is placed so that a central axis of the reducing agent injection device may be oriented along a front and rear direction of the work vehicle; and a selective catalytic reduction device is placed so that a central axis of the selective catalytic reduction device may be oriented along the front and rear direction of the work vehicle, in which the oxidation catalyst device, the reducing agent injection device, and the selective catalytic reduction device are arranged so as to have a relationship that the central axes thereof become the same in height, and the central axis of the selective catalytic reduction device is placed so as to pass through the oxidation catalyst device.

An exhaust system comprising: a NOx storage catalyst; an electric heating element; and a NOx reduction catalyst wherein the heating element is located downstream of the NOx storage catalyst.

A honeycomb structure includes: a honeycomb structure body including a plurality of cells; and a plugging portion to alternately plug open end parts of the plurality of cells on one side as an inflow side of the exhaust gas and open end parts on the other side as an outflow side of the exhaust gas. The partition wall is loaded, on the side of the outflow cells, with an oxidation catalyst made of a transition metal oxide to oxidize NO gas or an oxidation catalyst made of a transition metal oxide loaded at CeO.sub.2 to oxidize NO gas. The partition wall has porosity of 70% or less, the oxidation catalyst has a particle diameter of more than 1 μm and less than 50.0 μm, and the loading amount of the oxidation catalyst is 5.0 g/L or more and 50 g/L or less.