A vessel propulsion apparatus includes an engine and a propulsion unit to be driven by the engine. The engine includes cylinders arranged in series, exhaust ports respectively connected to combustion chambers of the cylinders and curved in a predetermined downstream direction to allow exhaust gases to flow out from the combustion chambers, and a collecting exhaust pipe. The collecting exhaust pipe is integral with the exhaust ports, and extends in the downstream direction to allow exhaust gases in the exhaust ports to flow in the downstream direction. At least one of a plurality of connector portions that individually connect the exhaust ports to the collecting exhaust pipe includes a concave portion at an inner surface thereof.

A cooling structure for an outboard motor comprises an oil case which has an oil chamber for storing lubricant oil for an engine. Said cooling structure further comprises: a main exhaust gas passage which guides exhaust gas to a lower side; a cooling water outbound path which guides cooling supply water taken from outside the outboard motor to an upper side, and cools the periphery of the main exhaust gas passage in the oil case by means of the cooling supply water; a cooling water inbound path which guides cooling discharge water that has cooled the engine to the lower side and cools the oil chamber by means of said cooling discharge water; and a mixed fluid passage which, on a side below the oil case, cools the exhaust gas by mixing the exhaust gas and the cooling discharge water.

A jet propelled watercraft includes a first exhaust pipe connected to an exhaust port, a catalyst storage connected to the first exhaust pipe, a second exhaust pipe connected to the catalyst storage, and a water lock connected to the second exhaust pipe. The catalyst storage and the water lock are located outward in a width direction with respect to the exhaust port of the engine in a plan view of the jet propelled watercraft.

A jet propelled watercraft includes a watercraft body, an engine housed in the watercraft body, a jet propulsion unit that suctions and jets water with a drive force of the engine, a first exhaust pipe connected to an exhaust port of the engine, and a catalyst storage connected to the first exhaust pipe, wherein the first exhaust pipe and the catalyst storage are integral and unitary with each other.

The present invention relates to an apparatus for reducing greenhouse gas emission in a vessel, and a vessel including the same, which are capable of satisfying IMO greenhouse gas emission regulations by separating and discharging NO.sub.x, SO.sub.x, and CO.sub.2 from exhaust gas exhausted from a vessel engine and increasing CO.sub.2 solubility and CO.sub.2 removal efficiency by removing CO.sub.2 after removing SO.sub.x.

A mobile emissions control system is provided for diesel engines operated on ocean-going ships at-berth. The emissions control system comprises two essential elements: an emissions capturing system and an emissions control system. The emissions control system may be mounted on a towable chassis or mounted on a barge, allowing it to be placed alongside ocean-going ships at-berth. The emission capturing system captures exhaust from a ship's diesel engine and conducts it into the emissions control system, which cleans the exhaust and then passes clean air into the atmosphere through an exhaust outlet.

An outboard motor includes a first exhaust passage connected to an exhaust port and extending downward from the exhaust port through a support frame on a lateral side of a cylinder head. A first case accommodates an engine. A second case accommodates a propeller shaft. A third case is between the first case and the second case in a vertical direction. An exhaust pipe is between the first case and the second case in the vertical direction. The exhaust pipe is connected to the first exhaust passage. At least a portion of the exhaust pipe is outside the third case as seen in a side view of the outboard motor. An exterior cover is between the first case and the second case in the vertical direction. The exterior cover covers the exhaust pipe.

An arrangement for treating exhaust gases of an internal combustion piston engine in a marine vessel, includes an exhaust gas channel coupled at its first end to the engine and having its second end opening to the environment, and a scrubber unit arranged between the first end and the second end of the exhaust gas channel. The arrangement has an exhaust gas channel cleaning system arranged to apply cleaning liquid on inner surface of the exhaust gas channel to a portion of the exhaust gas channel between the scrubber unit and the second end of the exhaust gas channel.

The present invention provide a method for purifying exhaust gas in which nitrogen oxides (NOx) gas is removed from a combustion exhaust gas. The method for purifying exhaust gas according to the invention is characterized in that water vapor is further added to raw exhaust gas to be processed to increase the water vapor concentration in the exhaust gas and the resulting moisture-adjusted exhaust gas is introduced into a denitration catalyst layer. The water vapor concentration in the moisture-adjusted exhaust gas is preferably 22.0% by volume or less in the total of the water vapor originally contained in the raw exhaust gas and the added water vapor.

A two-stage water-lift and water separation muffler for use with marine electrical generators installed onboard marine vessels. A first stage water-lift muffler has internal tunable sound suppression structure to provide a first stage of exhaust silencing, and a second stage water separator having internal tunable sound suppression structure to provide a second stage of exhaust silencing while separating entrained cooling water from exhaust gases. The combined first stage water-lift muffler and second stage water separator include internal baffling and silencing structure which is easily adaptable to different generator configurations thereby allowing for structural adjustments to the muffler to optimize sound suppression and minimize backpressure for particular generator and/or exhaust conditions.