Continuous fuel flow enhancer device for internal combustion engines has two internal solid phases in the fuel circulation where the following components intervene: silica gel (SiO2 nH2O) which performs a dehydration process, and in a second phase, activated carbon for organic compounds intervene, which performs an adsorption, purification and dehydration process.

An engine exhaust system includes an exhaust pipe assembly having an engine exhaust system inlet configured to receive engine exhaust and an engine exhaust system outlet. The system includes a first selective catalytic reduction (SCR) catalyst device positioned downstream in exhaust flow from the engine exhaust system inlet. The first SCR catalyst device includes a substrate with a metallic catalyst coated on the substrate. An electric heater is configured to heat the metallic catalyst. A second SCR catalyst device is positioned downstream in engine exhaust flow from the first SCR catalyst device and upstream of the engine exhaust system outlet. The first SCR catalyst device and the exhaust pipe assembly define an empty chamber between the substrate and the second SCR catalyst device. Engine exhaust flows directly from the substrate to the second SCR catalyst device through the empty chamber.

This catalyst system simultaneously removes ammonia and enhances net NOx conversion by placing an NH.sub.3-SCR catalyst formulation downstream of a lean NOx trap. By doing so, the NH.sub.3-SCR catalyst adsorbs the ammonia from the upstream lean NOx trap generated during the rich pulses. The stored ammonia then reacts with the NOx emitted from the upstream lean NOx trap-enhancing the net NOx conversion rate significantly, while depleting the stored ammonia. By combining the lean NOx trap with the NH.sub.3-SCR catalyst, the system allows for the reduction or elimination of NH.sub.3 and NOx slip, reduction in NOx spikes and thus an improved net NOx conversion during lean and rich operation.

An exhaust system injection section (10) includes an exhaust gas flow channel (19), a laterally arranged injector connection (21), with a fluid introducing injector (22) and an injection chamber (24) formed in the channel, which is delimited by a perforated first separating wall (25), arranged in the channel upstream of the injector connection, and a perforated second separating wall (26) arranged in the channel downstream of the injector connection. To provides intensive mixing of the injected fluid with the exhaust gas flow a perforation (29) of the first separating wall (25) is configured so that exhaust gas largely flows eccentrically through the first separating wall (25) with respect to a longitudinal center axis (23) of the channel and a perforation (31) of the second separating wall (26) is configured so that exhaust gas largely flows concentrically through the second separating wall (26) with respect to the longitudinal center axis (23).

Incorporated in an exhaust pipe are an HC-SCR NO.sub.x catalyst capable of reducing NO.sub.x at temperatures less than a set temperature T and a catalyzed particulate filter with an oxidation catalyst capable of reducing NO.sub.x at temperatures not less than the set temperature T. When an exhaust gas temperature is less than the set temperature T, fuel with a set flow rate Q is intermittently added from a fuel addition unit on an entry side of the HC-SCR NO.sub.x catalyst to the HC-SCR NO.sub.x catalyst; when the exhaust gas temperature is not less than the set temperature T, the fuel with flow rate Q′ not less than the set flow rate Q is temporarily rich-spike added from the fuel addition unit and is made arrival at a catalyzed particulate filter. With an active temperature range being expanded, exhaust emission control is performed in a wide temperature range.

An engine exhaust treatment apparatus, which suppresses thermal damage to an electrothermal ignition apparatus, includes: an exhaust passage; an oxidation catalyst disposed in the exhaust passage; a combustible gas generator; a combustible gas supplying passage; a heat dissipation port opened upstream in the exhaust passage from the oxidation catalyst and in a downstream part of the combustible gas supplying passage, the exhaust passage and the combustible gas supplying passage communicating with each other through the heat dissipation port; and an electrothermal ignition apparatus disposed in the combustible gas supplying passage. Heat of flaming combustion of the combustible gas ignited by the electrothermal ignition apparatus is supplied to the exhaust passage, to raise the temperature of exhaust in the exhaust passage. A heat dissipation plate is attached to an outer projecting portion of the electrothermal ignition apparatus. The outer projecting portion projects outside a wall of the exhaust treatment apparatus.

A method for controlling regeneration a catalyst by an exhaust gas purification device includes: measuring a temperature of exhaust gas flowing into a first catalyst unit; estimating a NO.sub.x amount loaded into the first catalyst unit and a slip amount of NO.sub.x of the first catalyst unit by using the temperature and an amount of the exhaust gas of the first catalyst unit; calculating a temperature of a second catalyst unit by using the temperature of the first catalyst unit; and estimating a NO.sub.x amount flowing into the second catalyst unit by using at least one of the slip amount of NO.sub.x of the first catalyst unit and the temperature of the second catalyst unit.

An exhaust gas purification system comprises an exhaust gas purification device which is arranged in an exhaust gas route of an engine, renewing devices for burning and removing a particulate matter within the exhaust gas purification device, renewal advance notifying means which is actuated in the case that a clogged state of the exhaust gas purification device becomes equal to or more than a prescribed level, and renewal informing means which informs of a fact that the renewing devices are under operation. The renewal advance notifying means is actuated before actuating the renewing devices.

An aftertreatment system (100) connected downstream an internal combustion engine arrangement (102) for receiving exhaust gases conveyed from the internal combustion engine arrangement (102) during operation thereof, wherein the aftertreatment system comprises first and second catalytic devices in series, wherein a gap is there between.

A heater is provided that includes at least one resistive heating element having a material with a non-monotonic resistivity vs. temperature profile and exhibiting a negative dR/dT characteristic over a predetermined operating temperature range along the profile. The heater can include a plurality of circuits disposed in a fluid path to heat fluid flow.