Abstract: A cylinder-shaped flow passage in which a first fluid flows includes an internal cylinder which is smaller in diameter than the flow passage. A swirl-generating stator having four vanes is radially fixed in the internal cylinder. A header space for supplying a second fluid is provided to the outer circumference of a wall surface of the internal cylinder in contact with flow separation areas which are formed along downstream surfaces of the swirl-generating stator as the first fluid runs into the swirl-generating stator. The wall surface of the internal cylinder is formed with openings through which the flow separation areas communicate with the header space. The second fluid supplied into the header space flows through the openings into the flow separation areas, and is diffused along the vanes of the swirl-generating stator to be swirled and mixed into the first fluid applied with swirling force by the swirl-generating stator.

Abstract: To provide an engine exhaust gas treatment system that can efficiently reduce and remove NOx using easy-to-handle urea as the reducing agent, regardless of the engine operating conditions. An exhaust gas denitration system in which an exhaust gas is introduced into the denitration catalyst reactor 5 provided in the exhaust gas flue 3, where NOx is reduced and removed in the presence of the denitrati on catalyst, wherein a diversion means provided in the exhaust gas flue 3 introduces part or all of the exhaust gas into a urea solution injection evaporator having a heating means by the heater 30, and the heat from the exhaust gas and the heat from the heater serve to generate ammonia that is then circled and mixed with the exhaust gas and introduced into the denitration catalyst reactor 4.

Abstract: An exhaust aftertreatment system comprises an injector for injecting urea water into an exhaust duct, and a denitration catalyst disposed downstream of the injector with respect to a flow of exhaust gas. The exhaust aftertreatment system reduces nitrogen oxides in the exhaust gas by the denitration catalyst while using ammonia produced from the urea water injected from the injector. The urea water is injected along a direction of the flow of the exhaust gas within the exhaust duct, and a porous plate is disposed in multiple stages in a space of the exhaust duct such that droplets of the injected urea water impinge against the porous plate before reaching a wall surface of the exhaust duct. A surface of the porous plate subjected to the impingement of the droplets is arranged to face downstream with respect to the flow of the exhaust gas.

Abstract: A cylinder-shaped flow passage in which a first fluid flows includes an internal cylinder which is smaller in diameter than the flow passage. A swirl-generating stator having four vanes is radially fixed in the internal cylinder. A header space for supplying a second fluid is provided to the outer circumference of a wall surface of the internal cylinder in contact with flow separation areas which are formed along downstream surfaces of the swirl-generating stator as the first fluid runs into the swirl-generating stator. The wall surface of the internal cylinder is formed with openings through which the flow separation areas communicate with the header space. The second fluid supplied into the header space flows through the openings into the flow separation areas, and is diffused along the vanes of the swirl-generating stator to be swirled and mixed into the first fluid applied with swirling force by the swirl-generating stator.

Abstract: To provide an engine exhaust gas treatment system that can efficiently reduce and remove NOx using easy-to-handle urea as the reducing agent, regardless of the engine operating conditions. An exhaust gas denitration system in which an exhaust gas is introduced into the denitration catalyst reactor 5 provided in the exhaust gas flue 3, where NOx is reduced and removed in the presence of the denitration catalyst, wherein a diversion means provided in the exhaust gas flue 3 introduces part or all of the exhaust gas into a urea solution injection evaporator having a heating means by the heater 30, and the heat from the exhaust gas and the heat from the heater serve to generate ammonia that is then circled and mixed with the exhaust gas and introduced into the denitration catalyst reactor 4.