The invention relates to a burner for gas-fired cooking appliances, with a structure comprised of: a body (10) defining a chamber (12) within which an injector (14) inputs the gas which, upon mixing with air, forms the gas-air combustible mixture; a ring (16) positioned over the body and provided with a periphery along which are arranged the combustible mixture outlet ports (18), and a circular plate (20) that closes the top of the burner. At least the burner ring (16) is made of a metal or a metal alloy and is coated with a thin layer of material having catalytic activity, which may be coated on a catalyst precursor porous support substrate.

A liquid-hydrocarbon fuel is used to produce thermal energy by introducing the liquid-hydrocarbon fuel and air to a vaporizer. The liquid-hydrocarbon fuel is vaporized in the vaporizer to produce hydrocarbon-fuel vapor, and the hydrocarbon-fuel vapor and air are blended to form a hydrocarbon-fuel-vapor-and-air mixture. Then, hydrocarbon-fuel-vapor-and-air mixture is introduced to a catalytic combustor including a catalyst, wherein the catalyst promotes oxidation of the hydrocarbon-fuel vapor to form a carbon-dioxide- and water-vapor-containing exhaust and to generate thermal energy. The carbon-dioxide- and water-vapor-containing exhaust and air is then introduced to a recuperator, wherein the recuperator transfers thermal energy from the carbon-dioxide- and water-vapor-containing exhaust to the air to produce heated air.

A steam generating system includes a nozzle assembly for pulverized coal and air, the coal nozzle assembly comprises an inner housing (3) for conveying primary air and coal and an outer housing (5) for conveying secondary air to an exit face (13) of a nozzle tip (1), wherein the outer housing (3) and the inner housing (5) are arranged coaxially and limit a channel (15) for the secondary air, wherein the cross-sectional area (A.sub.IH) of the inner housing (3) increases towards the exit face (13) of the nozzle tip (1), wherein the cross-sectional area (A.sub.OH) of the outer housing (5) decreases towards the exit face (13), and wherein bars (11) are located in the inner housing (3) near the exit face (13) that accelerate the velocity of the primary air and coal particles.

A burner system for a cooking device has at least one burner surface wherein the at least one burner surface is designed in such a way that the burner system has a low minimum power density with homogeneous temperature distribution at the same time. In a first aspect, the burner system includes a fuel supply and a first burner surface for burning the fuel that is provided downstream of the fuel supply. The burner system includes a second burner surface for afterburning that is separate from the first burner surface and is provided downstream from the first burner surface. Moreover, a method for operating the burner system is shown.

A micro-combustion device generating electrical power raises global performance of the system, is compact, and reduces losses by utilizing an induced helical path. The device includes: injection ducts inserting a combustion agent, a fuel and/or a mixture thereof wherein the injection of the combustion agent takes place tangentially to the internal cylindrical wall, inducing a helical combustion path, the internal cylindrical walls of the chamber having a deposition of catalytic material to accelerate the combustion reaction; a turbo compressor group, including a compressor, feeding under pressure the combustion chamber through the injection ducts, and a turbine, receiving the flue gases from the discharge duct, compressor and turbine being keyed on the same axis, whereon a generator of electrical power, in turn, is keyed; and a fuel cell, fed by the flue gases through the turbine and by an oxidizing agent, implementing an electrochemical process generating additional electrical power.

A micro-combustion device generating electrical power raises global performance of the system, is compact, and reduces losses by utilizing an induced helical path. The device includes: injection ducts inserting a combustion agent, a fuel and/or a mixture thereof wherein the injection of the combustion agent takes place tangentially to the internal cylindrical wall, inducing a helical combustion path, the internal cylindrical walls of the chamber having a deposition of catalytic material to accelerate the combustion reaction; a turbo compressor group, including a compressor, feeding under pressure the combustion chamber through the injection ducts, and a turbine, receiving the flue gases from the discharge duct, compressor and turbine being keyed on the same axis, whereon a generator of electrical power, in turn, is keyed; and a fuel cell, fed by the flue gases through the turbine and by an oxidizing agent, implementing an electrochemical process generating additional electrical power.

A reactor for a mixture of fluids that can react with each other exothermically, the reactor combining the properties of heat transfer and porosity, and having a first chamber wherein reacted fluids are maintained above the reaction temperature threshold, a second chamber disposed adjacent to the first chamber, wherein unreacted fluids enter the second chamber at a temperature that is below a reaction temperature threshold that is necessary for reaction of the fluids to occur, the fluids flowing in a second direction, opposite the first direction and a porous wall disposed between the first chamber and a second chamber, allowing portions of the unreacted fluids from the second chamber to seep into the reacted fluids of the first chamber, thereby heating the seeped fluids, causing the seeped fluids to react, the reaction increasing the temperature of the reacted fluid.

A steam generating system includes a nozzle assembly for pulverized coal and air, the coal nozzle assembly comprises an inner housing (3) for conveying primary air and coal and an outer housing (5) for conveying secondary air to an exit face (13) of a nozzle tip (1), wherein the outer housing (3) and the inner housing (5) are arranged coaxially and limit a channel (15) for the secondary air, wherein the cross-sectional area (A.sub.IH) of the inner housing (3) increases towards the exit face (13) of the nozzle tip (1), wherein the cross-sectional area (A.sub.OH) of the outer housing (5) decreases towards the exit face (13), and wherein bars (11) are located in the inner housing (3) near the exit face (13) that accelerate the velocity of the primary air and coal particles.

A coal nozzle assembly for a steam generation apparatus comprising an elongated nozzle body having a nozzle tip at one end thereof; said nozzle tip comprising two channels, each channel having curved or buckled flow paths, the nozzle tip further comprising parting means separating the channels from each other, wherein the directions of the flow paths of the channels at their ends distal from the nozzle body enclose an angle between 0 and 90. This promotes intersecting and shearing the two partial streams outside the nozzle assembly resulting in a better combustion with reduced NOx-emissions.

A heater having a planar metal sheet with a first and second surface. A metal oxide layer is formed on the first surface of the sheet and a combustion catalyst is impregnated into the metal oxide layer. A source of fuel and air is then supplied to the first side of the metal sheet resulting in catalytic combustion which heats the metal sheet. The metal sheet can serve as a cooking stove.