Disclosed is a gas furnace including a mixer configured to mix air and fuel gas introduced from an intake pipe and a manifold respectively so as to produce an air-fuel mixture, a mixing pipe configured to allow the air-fuel mixture having passed through the mixer to flow therein, a burner assembly configured to combust the air-fuel mixture having passed through the mixing pipe so as to generate combustion gas, heat exchangers configured to allow the combustion gas to flow therein, an exhaust pipe configured to discharge exhaust gas, which is the combustion gas having passed through the heat exchangers, to the outside. The gas furnace further includes a recirculator installed around the exhaust pipe and configured to guide a portion of the exhaust gas flowing in the exhaust pipe to the mixer, and may thus greatly reduce or fundamentally block NO.sub.x emissions.

A cylindrical burner apparatus and method which produce low NO.sub.x emissions and low noise levels without being dependent upon a blower, or natural draft, for providing air flow. A flow of combustion air is induced into a cylindrical burner lube by discharging a gas fuel from a plurality of discharge ports located inside the rearward end of the tube. At least some of the discharge ports are oriented to direct jets of the gas fuel toward flame stabilization structures positioned downstream of the discharge ports.

A system and method for generating combustion aerosols from liquid fuel. The system includes a furnace with an inner heating tube having a heating tape wrapped thereabout. Further, the system includes a fuel line extending through an inlet end of the heating tube and into the heating tube, and a means for dripping the liquid fuel onto a plurality of different locations on an inner surface of the heating tube. The system further includes a power supply to power the heating tape to heat the inner heating tube to a temperature which can ignite the liquid fuel dripped onto the inner surface of the inner heating tube whereby there is an immediate combustion to form combustion products. Finally, the system includes an air line connected to the heating tube for directing compressed air through the inner heating tube to mix with the combustion products and transport the formed combustion aerosols out of an outlet end of the inner heating tube.

A system and method uses a combustor and gasifier to burn a primary dirty fuel, such as waste materials or high-polluting fossil fuels, and a secondary low-polluting fuel, such as biomass fuels, for co-generation of electricity while reducing harmful emissions. The primary fuel is burned at least partially through the use of an improved burner tube. Dirty exhaust from a combustor is scrubbed by a gasifier by reforming the combustors exhaust gases into a clean-burning producer gas (syn-gas). The secondary fuel and oxygen are added to the dirty exhaust in the gaslifier to create gas, char and ash. The gas powers an engine or turbine that turns a generator, or a boiler, Stirling engine, or Organic Rankine Cycle power plant, and releases a cleaner exhaust.

A cylindrical burner apparatus and method which produce low NO.sub.x emissions and low noise levels without being dependent upon a blower, or natural draft, for providing air flow or flue gas recirculation. A flow of combustion air is induced into the initial tube pass of the burner by discharging a gas fuel from a plurality of discharge ports located in the initial tube pass. At the same time, a flow of recycled flue gas is induced through a bypass duct between a subsequent tube pass of the burner and the initial tube pass by discharging one or more jets of gas fuel through the bypass duct.

A combustion tube assembly of a water heater includes a combustion tube having an open end, a closed end, and an outflow opening located between the open end and the closed end. A cavity of the combustion tube provides a chamber for a combustion of a water heater fuel that produces an exhaust gas that flows down toward the closed end. The combustion tube assembly further includes a diverter structure positioned inside the combustion tube to divert the exhaust gas such that the exhaust gas flows toward the closed end on a first side of the diverter structure and flows from the first side of the diverter structure to the second side of the diverter structure through a flow opening proximal to the closed end. The outflow opening provides an outlet for the exhaust gas that flows to the second side of the diverter structure to exit the combustion tube.

A combustion tube assembly of a water heater includes a combustion tube having an open end, a closed end, and an outflow opening between the open end and the closed end. A cavity of the combustion tube provides a chamber for a combustion of a water heater fuel, where the outflow opening provides an outlet for an exhaust gas resulting from the combustion of the water heater fuel to exit the combustion tube. The combustion tube assembly further includes a spring positioned in the cavity of the combustion tube at the closed end of the combustion tube.

A burner includes a porous flame holder configured to support a combustion reaction to achieve a very low output of oxides of nitrogen (NOx).

A combustion chamber with a jacket arranged around a principal axis of the combustion chamber, a ceramic tube that is arranged inside the jacket, wherein an intermediate layer is arranged between the jacket and the ceramic tube. The jacket is at least partially conical. The ceramic tube is under axial stress in the jacket along the principal axis. The ceramic tube is an assembly of multiple heat shield segments. The heat shield segments each have a hot side that is designed to come into contact with a hot medium, a cold side that is opposite the hot side and is oriented toward the jacket, and a circumferential rim between the hot side and the cold side. In the cold state, individual heat shield segments of a segment row have, on the rim, bearing surfaces that the adjoin the cold side and gaps that open toward the hot gas side.

An infrared radiation heater includes: a combustion chamber having a combustion space that is open on one side; a combustion device provided in the combustion chamber to combust air-fuel mixture made by mixing fuel with air; and a radiator configured to be heated by heat generated from the combustion device and including a radiation plane configured to emit infrared radiation. The combustion device includes: a nozzle provided in a flow path of the air to inject the fuel; a tubular body including a side surface that faces a direction with a predetermined angle with respect to the radiation plane, and a plurality of voids being formed on the side surface; and an ignition device provided outside of the tubular body and configured to ignite the air-fuel mixture. The air-fuel mixture flows into the tubular body, and the tubular body releases the air-fuel mixture from the voids into the combustion chamber.