Engine systems use a three-way catalyst followed by air injection and mixing to convert all hydrocarbons and carbon monoxide under various load conditions when exhaust gas temperature is above 500 degrees Celsius. A three-way catalytic converter is disposed in the exhaust system. A nozzle is configured to inject air into the exhaust system downstream from the three-way catalytic converter. A mixing plate with or without catalyst coatings is disposed in the exhaust system downstream from the nozzle. The mixing plate is bow shaped with a concave shaped side facing the nozzle to enhance carbon monoxide conversion. Optional two way catalytic converters are added downstream from the mixing plate to further reduce tailpipe hydrocarbon and carbon monoxide emissions.

An exhaust aftertreatment arrangement for cleaning exhaust gases includes a fluid channel for providing a fluid pathway for the exhaust gases, a selective catalyst reduction, SCR, catalyst, arranged in or downstream the fluid channel, a heating arrangement for heating the exhaust gases, the heating arrangement being arranged upstream of the SCR catalyst and comprising an electrical heating element, a first fluid pathway for guiding the exhaust gases to the electrical heating element, and a second fluid pathway for guiding the exhaust gases to bypass the electrical heating element, wherein the heating arrangement is removably arranged relative the fluid channel.

An exhaust gas treatment system includes an exhaust gas pathway configured to receive exhaust gas from an internal combustion engine. The exhaust gas treatment system further includes a treatment element configured to reduce an emissions component of the exhaust gas, and a sample collector positioned within the exhaust gas pathway downstream of the treatment element. The sample collector includes a plurality of inlet openings spaced about a periphery of the exhaust gas pathway and configured to receive a sample of exhaust gas from the exhaust gas pathway, and an outlet in fluid communication with the plurality of inlet openings. A sensor located at the outlet of the sample collector is configured to measure a characteristic of the sample.

A mixer for a vehicle exhaust gas system includes a mixer housing defining an internal cavity and having a mixer inlet configured to receive exhaust gas and a mixer outlet to direct exhaust gas to downstream exhaust components. A flow device is configured to receive the exhaust gas from the mixer inlet and to facilitate mixing of the exhaust gas and a reductant introduced into the first flow device. The flow device comprises a Venturi body centered on a body center axis, and the Venturi body comprises a body inlet configured to receive the exhaust gas from the mixer inlet and a body outlet configured to provide the exhaust gas to the mixer outlet. The Venturi body also includes a louver extending from an internal surface of the mixer housing to a distal edge that is downstream of the body outlet. An upstream vane is positioned within the Venturi body proximate the body inlet and is coupled to an upstream vane hub that is centered on an upstream vane hub axis. A downstream vane is positioned within the Venturi body proximate the body outlet and is coupled to a downstream vane hub that is centered on a downstream vane hub axis. The upstream vane hub axis is radially offset from the body center axis by an offset distance and/or the downstream vane hub axis is radially offset from the body center axis by an offset distance.

An exhaust system for an internal combustion engine, in the exhaust duct of which a sensor is arranged for determining the exhaust gas composition. Furthermore, upstream of the sensor a guide vane is arranged, which is designed to increase the flow velocity of the exhaust gas in a local flow cross-section of the exhaust duct at the height of the sensor. This makes it possible to provide sufficiently high flow velocities of the exhaust gas at the sensor.

An exhaust gas treatment arrangement for an exhaust gas system of an internal combustion engine includes an exhaust gas channel leading to a flow path switching unit. The flow path switching unit is configured for changing exhaust gas parts of an exhaust gas stream flowing through the exhaust gas channel, which are conducted into first and second exhaust gas flow paths downstream of the flow path switching unit. The first exhaust gas flow path and the second exhaust gas flow path lead to an exhaust gas outlet. An SCR catalyst unit is in the first exhaust gas flow path upstream of the exhaust gas outlet. A liquid bypass line drains liquid from a liquid collection region in the exhaust gas channel upstream relative to the switching unit. The liquid is drained to a liquid discharge region for discharging liquid into the second flow path downstream of the switching unit.

An exhaust structure for a saddle riding vehicle includes: an exhaust pipe connected to an internal combustion engine; and a catalyst disposed in the exhaust pipe; the exhaust pipe including a catalyst case unit housing the catalyst and upstream side exhaust pipes disposed on an upstream side of the catalyst case unit; the catalyst case unit having a larger diameter than the upstream side exhaust pipes; the upstream side exhaust pipes being connected to the catalyst case unit in a connecting portion located on an upstream side of the catalyst in a flow of exhaust; in the connecting portion, axes of the upstream side exhaust pipes and an axis of the catalyst case unit being in substantially right-angled positional relation to each other.

An exhaust treatment assembly for receiving exhaust gas from a motor vehicle includes a mix pipe, a sheath, and a heater. The mix pipe at least partially defines a passage adapted to receive the exhaust gas and a chemical reductant. The sheath includes a first end fluidly sealed to the mix pipe. At least a portion of the sheath is radially spaced apart from the mix pipe to at least partially define a gap. The heater is disposed in the gap. The heater is adapted to heat a reductant impingement surface.

A reaction device of a marine SCR system comprises a conveying unit (110), a reaction chamber (120), at least one catalyst module (130), and an air homogenization chamber (140), wherein, the conveying unit (110) includes an input pipeline (111) and an output pipeline (112) sleeved outside the input pipeline (111). One end of the reaction chamber (120) is connected to the conveying unit (110). The reaction chamber (120) comprises an inner cylinder (121) and an outer cylinder (122) sleeved outside the inner cylinder (121), the inner cylinder (121) is in communication with the input pipeline (111), and the outer cylinder (122) is in communication with the output pipeline (112). The catalyst module (130) is provided between the inner cylinder (121) and the outer cylinder (122). The air homogenization chamber (140) is connected to the other end of the reaction chamber (120) and is in communication with both the inner cylinder (121) and the outer cylinder (122). With the reaction device of the marine SCR system whereby the outer cylinder is sleeved outside the inner cylinder, flue gas from the inner cylinder is turned by the air homogenization chamber and then flows back into the outer cylinder. This can not only substantially reduce the size of the reaction device to improve the integration of the SCR system, but also allow the flue gas to turn in the air homogenization chamber and then flow back, so that the flue gas and a reducing agent can be fully mixed in the air homogenization chamber to improve the catalytic reaction efficiency.

An exhaust gas system for an internal combustion engine includes at least one component which delimits an exhaust gas flow volume via an outer wall and, on an inner side of the outer wall which faces the exhaust gas flow volume, supports at least one shielding element. An intermediate space is formed between the outer wall and the shielding element. At least one connecting molding on the shielding element is directed toward the outer wall and is connected fixedly to the outer wall.