A linear reciprocating engine may include a cylinder having a first combustion chamber at one end and a second combustion chamber at an opposing end, first and second cylinder heads located at an end of the first and second combustion chambers, respectively, and a double-faced piston slidably mounted within the cylinder. The engine may further include a first piston rod portion extending from a first face of the double-faced piston through the first combustion chamber, and a second piston rod portion extending from a second face of the piston through the second combustion chamber. Passageways in the piston rod portions may be configured to communicate gases between the combustion chamber and a location outside the cylinder and configured to prevent gases from being exchanged between the cylinder and a location outside the cylinder via a path that crosses both face of the piston.

Provided is an exhaust gas purification device provided with a cover which can reduce radiated noise at low cost without impairing the heat shield function of the cover. Provided is an exhaust gas purification device comprising: an exhaust gas purification device body provided to the exhaust pipe of a diesel engine and purifying exhaust gas; and a substantially rectangular cover provided so as to cover at least a part of the exhaust gas purification device body and blocking heat radiated from the exhaust gas purification device body. The cover is provided with a plurality of protruding ribs formed on the surface thereof. The ribs comprise: radial ribs formed extending radially from a center section centered at the intersection of the diagonals of the cover; and a circumferential rib formed continuously along the entire circumference of a circle centered at the intersection.

Provided is an exhaust gas purification device provided with a cover which can reduce radiated noise at low cost without impairing the heat shield function of the cover. Provided is an exhaust gas purification device comprising: an exhaust gas purification device body provided to the exhaust pipe of a diesel engine and purifying exhaust gas; and a substantially rectangular cover provided so as to cover at least a part of the exhaust gas purification device body and blocking heat radiated from the exhaust gas purification device body. The cover is provided with a plurality of protruding ribs formed on the surface thereof. The ribs comprise: radial ribs formed extending radially from a center section centered at the intersection of the diagonals of the cover; and a circumferential rib formed continuously along the entire circumference of a circle centered at the intersection.

A heating device for an exhaust system of an internal combustion engine and having: a main tubular body, which contains a combustion chamber delimited by a first base wall and by a second base wall, which are opposite one another; a fuel injector configured to inject fuel; an inlet opening, which can be connected to a fan to receive an air flow, which is directed to the combustion chamber and gets mixed with fuel; a secondary tubular body which is arranged inside the main tubular body and inside the combustion chamber and has a side wall, which is arranged at a given distance from the side wall of the main tubular body so as to divide an initial part of the combustion chamber into a central zone, which is located inside the secondary tubular body, and an annular peripheral zone, which is located around the secondary tubular body.

A heating device for an exhaust system of an internal combustion engine and having: a main tubular body, which contains a combustion chamber delimited by a first base wall and by a second base wall, which are opposite one another; a fuel injector configured to inject fuel; an inlet opening, which can be connected to a fan to receive an air flow, which is directed to the combustion chamber and gets mixed with fuel; a secondary tubular body which is arranged inside the main tubular body and inside the combustion chamber and has a side wall, which is arranged at a given distance from the side wall of the main tubular body so as to divide an initial part of the combustion chamber into a central zone, which is located inside the secondary tubular body, and an annular peripheral zone, which is located around the secondary tubular body.

A piston is provided for an internal combustion engine. The piston may include a cylindrical first piston portion having a first diameter, a cylindrical second piston portion of the first diameter, and a cylindrical third piston portion of a second diameter less than the first diameter located between the first piston portion and the second piston portion. The first piston portion may be configured such that prior to assembly, the first piston portion is separate from the second piston portion. The piston may also include a continuous, gapless piston ring circumscribing the third piston portion, where the piston ring may be configured such that when heated the piston ring deforms in an axial direction of the piston.

A device for generating a reducing agent gas from a solid or liquid reducing agent, where the reducing agent gas is preferably suited for nitrogen oxide reduction in an exhaust gas of a combustion engine, the device including a reactor with an inner volume and an inlet for a reducing agent solution and an outlet for the reducing agent gas. The device further including a heating system disposed at least partially in the inner volume and a heating control unit for controlling the heating system, wherein the inner volume includes first and second heating zones each including at least one heating element and controlled independently of each other by the heating control unit.

A device for generating a reducing agent gas from a solid or liquid reducing agent, where the reducing agent gas is preferably suited for nitrogen oxide reduction in an exhaust gas of a combustion engine, the device including a reactor with an inner volume and an inlet for a reducing agent solution and an outlet for the reducing agent gas. The device further including a heating system disposed at least partially in the inner volume and a heating control unit for controlling the heating system, wherein the inner volume includes first and second heating zones each including at least one heating element and controlled independently of each other by the heating control unit.

A nitrogen oxide reduction type regenerative thermal oxidation system and a method for nitrogen oxide reduction thereof are disclosed. The nitrogen oxide reduction type regenerative thermal oxidation system according to the present invention is characterized by comprising: a first reduction device for primarily reducing nitrogen oxides generated by a regenerative thermal oxidation device based on a selective non-catalytic reduction method; an exhaust gas storage device for storing the exhaust gas being discharged from the regenerative thermal oxidation device; a second reduction device for secondarily reducing nitrogen oxides based on a selective catalytic reduction method for an exhaust gas stored in the exhaust gas storage device; and a suction and discharge device for sucking in the exhaust gas with secondarily reduced nitrogen oxides from the exhaust gas storage device and discharging it into the atmosphere.

A nitrogen oxide reduction type regenerative thermal oxidation system and a method for nitrogen oxide reduction thereof are disclosed. The nitrogen oxide reduction type regenerative thermal oxidation system according to the present invention is characterized by comprising: a first reduction device for primarily reducing nitrogen oxides generated by a regenerative thermal oxidation device based on a selective non-catalytic reduction method; an exhaust gas storage device for storing the exhaust gas being discharged from the regenerative thermal oxidation device; a second reduction device for secondarily reducing nitrogen oxides based on a selective catalytic reduction method for an exhaust gas stored in the exhaust gas storage device; and a suction and discharge device for sucking in the exhaust gas with secondarily reduced nitrogen oxides from the exhaust gas storage device and discharging it into the atmosphere.