A burner for heating a heating space with a reduction of NOx emissions is provided. The burner includes a mixing and combustion chamber, a mixing and igniting device disposed in the mixing and combustion chamber, and a fuel feed connected to the mixing and igniting device and configured for feeding fuel to the mixing and igniting device. Further, an air feed is provided, which is configured for feeding at least one partial air flow to the mixing and combustion chamber. A combustion chamber opening opens the mixing and combustion chamber towards a heating space to be heated. Furthermore, control means are configured for controlling a fuel flow via the fuel feed and for controlling at least one partial air flow via the air feed.

A method directs fuel-oxidant premix into a reaction zone through a first total premix inlet flow area, and causes the premix to combust and form a stable flame projecting into a process chamber through an outlet from the reaction zone. At a time when the process chamber has a temperature at or above an auto-ignition temperature of the fuel, the flame is blown off to initiate diffuse combustion in the process chamber without a stable flame. The flame is blown off by directing the premix into the reaction zone through a second total premix inlet flow area greater than the first total premix inlet flow area.

A method supplies reactants, including fuel gas, to burners that discharge the reactants into a furnace process chamber. In a stable flame mode of operation, stable flames are projected from the burners into the furnace process chamber. At a time when the furnace process chamber has a temperature at or above an autoignition temperature of the fuel gas, a diffuse combustion mode is initiated by supplying a selected burner with additional reactants, including reactants diverted from another burner, to blow off the stable flame at the selected burner.

Is provided a method for starting up a pressurized fluidized bed incinerator system by which cracking of silica sand as a bed material can be prevented at low costs. By heating the silica sand as the bed material filled up in a bottom portion of a pressurized fluidized bed incinerator, a temperature of a freeboard of the incinerator is heated, and after the temperature of the freeboard is heated to 750 to 900 C., a material to be treated having a water-containing organic substance is fed to the pressurized fluidized bed incinerator.

A burner for heating a heating space with a reduction of NOx emissions is provided. The burner includes a mixing and combustion chamber, a mixing and igniting device disposed in the mixing and combustion chamber, and a fuel feed connected to the mixing and igniting device and configured for feeding fuel to the mixing and igniting device. Further, an air feed is provided, which is configured for feeding at least one partial air flow to the mixing and combustion chamber. A combustion chamber opening opens the mixing and combustion chamber towards a heating space to be heated. Furthermore, control means are configured for controlling a fuel flow via the fuel feed and for controlling at least one partial air flow via the air feed.

A method directs fuel-oxidant premix into a reaction zone through a first total premix inlet flow area, and causes the premix to combust and form a stable flame projecting into a process chamber through an outlet from the reaction zone. At a time when the process chamber has a temperature at or above an auto-ignition temperature of the fuel, the flame is blown off to initiate diffuse combustion in the process chamber without a stable flame. The flame is blown off by directing the premix into the reaction zone through a second total premix inlet flow area greater than the first total premix inlet flow area.