In an oxyfuel combustion boiler system, nitrogen gas separated by an air separation unit (ASU) is supplied as carrier gas to a pulverizer for drying and pulverization of fuel. A fluid mixture of the nitrogen gas from the pulverizer with pulverized fuel is supplied to a powder separation device where the pulverized fuel is separated. The separated pulverized fuel is mixed with the primary recirculated flue gas and supplied to a burner.

A cylindrical furnace having a vertical axis controls combustion. Solid fuel, particulates, and gases inside the furnace rotate around the axis, inducing radial stratification using centrifugal forces. Fuel and particulates drag on the wall of the cylinder, slipping in and out of suspension, thereby increasing particle residence times. The solid particles comprise combustible fuel particles, and non-combustible ash and contaminants. Control of the temperature of non-combustible particles and the wall surface prevents these non-combustible particles from adhering to, and building up on, the furnace wall. It is also advantageous to control the gas temperature leaving the furnace to minimize temperature-driven corrosion of downstream heat-exchange surfaces. Method and apparatuses are described to control the gas, non-combustible particle, and wall temperatures. The furnace can be integrated into a stand-alone boiler or as a combustor in which a portion of the pyrolysis gas from the combusting fuel is burned in a separate vessel.

A method includes providing a furnace including a radiant heating zone having metal heating coils and burners, concurrently applying a combustion media, having a combustibility, and a diluent to the burners, the burners burning the combustion media producing flames heating the radiant heating zone, and the diluent reducing the combustibility of the combustion media for reducing heat generated by the flames for reducing heat degradation of the metal heating coils.

A combustion method in which heated flue gas heats a regenerator through which a mixture of fuel and flue gas is then passed to undergo endothermic reactions that produce syngas which is fed into a furnace together with a motive gas stream.

In one embodiment, a system includes a turbine combustor having a combustor liner disposed about a combustion chamber, a head end upstream of the combustion chamber relative to a downstream direction of a flow of combustion gases through the combustion chamber, a flow sleeve disposed at an offset about the combustor liner to define a passage, and a barrier within the passage. The head end is configured to direct an oxidant flow and a first fuel flow toward the combustion chamber. The passage is configured to direct a gas flow toward the head end and to direct a portion of the oxidant flow toward a turbine end of the turbine combustor. The gas flow includes a substantially inert gas. The barrier is configured to block the portion of the oxidant flow toward the turbine end and to block the gas flow toward the head end within the passage.

A combustion method in which heated flue gas heats a regenerator through which a mixture of fuel and flue gas is then passed to undergo endothermic reactions that produce syngas which is fed into a furnace together with a motive gas stream, wherein fuel is combusted with the motive gas stream to provide heat in alternate cycles.

The invention relates to a burner for forming a flame in a furnace by means of gaseous fuel and combustion air (I), simultaneously recirculating flue gases in the furnace, wherein the burner comprises a burner frame and a combustion head connected to the same by its cylindrical body, wherein the end portion of the combustion head facing the furnace extends at its first end to the furnace, and the second end of the end portion is connected to said cylindrical body, a primary gas pipe for supplying gaseous fuel (G; G1) to the furnace, wherein the primary gas pipe extends inside the combustion head in its longitudinal direction, particularly inside of the end portion of the combustion head, and the orifice of the primary gas pipe opens into or close to the furnace, and a primary air supply pipe also extends inside the combustion head and surrounds said primary gas pipe, and the orifice of the supply pipe opens into the furnace or to the orifice of the end portion of the combustion head, a flow duct for main combustion air (Imain) extending inside the combustion head and surrounding said primary air supply pipe at least inside of the end portion, and a set of main gas rods, comprising a set of elongated primary gas rods extending in the longitudinal direction of the combustion head, for supplying the furnace with fuel, wherein the main gas rods are arranged at least partly outside the cylindrical body of the combustion head, extending close to the joint between the cylindrical body and the end portion so that they are surround said body at regular intervals around the circumference of the body, and wherein in connection with the main gas rods, at the end portion of the combustion head, several ejector ducts are provided for recirculating flue gas from the furnace into the gaseous fuel (G; G2) coming from the main gas rods, and for conveying the produced flue gas-flue mixture (S+G2) further to the furnace.

A method of operating an axial stage combustion system in a gas turbine engine (12) including an EGR system (14) that extracts a portion of exhaust gas produced by the gas turbine engine (12) to a second axial stage of a combustor (18). The extracted exhaust gas is provided at an elevated temperature to a group of injector nozzles (50) at the second axial stage (34) of the combustor (18). A secondary fuel supply line (34) extends to an inlet on each of the injector nozzles (50), and the fuel is mixed with the exhaust gas within the injector nozzles (50) and the mixture of fuel and exhaust gas is injected into the second axial stage (34) of the combustor (18).

Disclosed is a thermochemical regenerative combustion method in which a mixture of fuel components that can, and cannot, undergo endothermic reaction is passed through a heated regenerator to obtain improved heat recovery efficiency.

A reaction chamber for a feedstock reactor includes an outer shell defining a reaction volume and having a heat-resistant refractory, an inlet for allowing a feedstock to enter the reaction volume, an outlet for allowing reaction products, formed as a result of decomposition of the feedstock in the reaction volume, to exit the reaction volume, and a protective liner lining an interior surface of the outer shell and comprising a compliant shock-absorbing layer.