Abstract: A solid-fuel burner includes: a venturi having a constricting portion where the transverse cross section of a fuel passage is reduced in a fuel nozzle for supplying a solid fuel; and a fuel concentrator for diverting the flow in the nozzle outward in the wake side of the venturi, and the nozzle is formed so that (a) the aperture in the vicinity of an opening portion of a boiler furnace wall surface has a flat shape, (b) cross-sectional shape thereof orthogonal to a nozzle center axis C on the outer peripheral wall of the nozzle is circular in a transverse cross section up to the constricting portion of the venturi, (c) a portion that has a gradually increasing degree of flatness is provided between the constricting portion and the opening portion, and (d) the flat shape in the opening portion is where the degree of flatness reaches a maximum.

Abstract: A solid-fuel burner includes: a venturi having a constricting portion where the transverse cross section of a fuel passage is reduced in a fuel nozzle for supplying a solid fuel; and a fuel concentrator for diverting the flow in the nozzle outward in the wake side of the venturi, and the nozzle is formed so that (a) the aperture in the vicinity of an opening portion of a boiler furnace wall surface has a flat shape, (b) cross-sectional shape thereof orthogonal to a nozzle center axis C on the outer peripheral wall of the nozzle is circular in a transverse cross section up to the constricting portion of the venturi, (c) a portion that has a gradually increasing degree of flatness is provided between the constricting portion and the opening portion, and (d) the flat shape in the opening portion is where the degree of flatness reaches a maximum.

Abstract: A solid fuel burner and a combustion device using the solid fuel burner includes: a throat provided to the outer periphery of a fuel nozzle and injecting combustion gas into a furnace; a duct for delivering the combustion gas to the throat, the duct being provided with an inlet opening into which the gas is introduced from a direction perpendicular to the central axis of the nozzle and having a flow path formed so as to be bent at a right angle in the direction of the central axis of the nozzle; a damper provided in the duct; and a differential pressure detection device for detecting the difference between the pressure of the combustion gas flowing through the upstream portion of the duct and the pressure of the combustion gas flowing through the downstream portion of the duct. The damper is provided near and downstream of the inlet opening of the duct.

Abstract: A pulverized coal burning boiler is provided, which reduces an air-excess ratio thereby to reduce the emission of unburned contents such as CO. The pulverized coal burning boiler includes a pulverized coal feed measuring device for measuring the feeding rates of the pulverized coal to be conveyed through coal feeding pipes, individually, and a control device for calculating the burning air feeding rates to match the pulverized coal feeding rates thereby to send a control command signal to burning air feed adjusting device, so that a burner air ratio set by a burner air ratio setting device may be kept on the basis of both the pulverized coal feeding rate, which is measured by the pulverized coal feed measuring device, and the burning air feeding rate, which is measured by the burning air feeding rate measuring device and fed to a pulverized coal burner connected to the coal feeding pipes.

Abstract: A combustion burner includes a mixture nozzle (2) defining a mixture fluid passage through which a mixture fluid (1) containing pulverized coal and conveyor gas flows toward a furnace, secondary and tertiary air passages surrounding the mixture nozzle (2), through which secondary air (6) and tertiary air (9) for combustion purposes flow, respectively; and air injection nozzles (24) provided in the vicinity of an outer periphery of a distal end of the mixture nozzle (2). The air (21) is injected from the air injection nozzles (24) toward the axis of the mixture nozzle, so that the high-temperature gas in the vicinity of the outer periphery of the distal end of the mixture nozzle (2) is drawn into the mixture fluid (1) in the vicinity of the outer periphery of this distal end.