Abstract: A solid fuel burner to be inserted into a burner throat bored in a wall portion of a furnace, comprising: a solid fuel nozzle for ejecting mixed fluid of solid fuel and primary air; a secondary air nozzle for ejecting secondary air; a tertiary air nozzle for ejecting tertiary air; a secondary air guide member for guiding a flow of the secondary air outwardly in a radial direction; and one or more tertiary air guide members for guiding a flow of the tertiary air outwardly in the radial direction at a first angle with respect to a central axis (C) of the solid fuel burner, wherein a distal end position (X2) of each of the tertiary air guide members in an axial direction of the solid fuel burner is at a closer side of the furnace than a distal end position (X1) of the secondary air guide member.

Abstract: A burner characterized by being equipped with: a fuel supply nozzle to which a mixed flow of a solid fuel and a solid fuel transport gas is supplied; a flow passage that is arranged on the outside of the fuel supply nozzle and that supplies combustion air separated from the mixed flow; and ammonia supply nozzles which are capable of supplying ammonia on the downstream side of the outlet of the fuel supply nozzle toward a reduction region in which oxygen in the transport gas has been consumed due to ignition of the fuel and the progress of combustion, resulting in a low oxygen concentration. Thus, it is possible to provide a burner capable of burning a mixture of a solid fuel and ammonia, and a combustion device equipped with this burner.

Abstract: This solid fuel burner is provided with: a venturi tube in which a channel for mixed fluid in a fuel nozzle narrows toward the center in the channel cross section; a fuel concentrator that imparts, to the mixed fluid, a velocity component away from the center of the fuel nozzle; and a channel separation member that separates the channel of the fuel nozzle into an internal side and an external side; wherein the channel separation member is shaped in such a way that the cross sectional area of an external channel is larger at the downstream end than at the upstream end, and the upstream end of the fuel concentrator is located between the upstream end and the downstream end of an expanded portion of the venturi tube. This solid fuel burner prevents solid fuel particles, which is ground biomass fuel, from adhering and depositing inside the nozzle.

Abstract: A burner characterized by being equipped with: a fuel supply nozzle to which a mixed flow of a solid fuel and a solid fuel transport gas is supplied; a flow passage that is arranged on the outside of the fuel supply nozzle and that supplies combustion air separated from the mixed flow; and ammonia supply nozzles which are capable of supplying ammonia on the downstream side of the outlet of the fuel supply nozzle toward a reduction region in which oxygen in the transport gas has been consumed due to ignition of the fuel and the progress of combustion, resulting in a low oxygen concentration. Thus, it is possible to provide a burner capable of burning a mixture of a solid fuel and ammonia, and a combustion device equipped with this burner.

Abstract: A solid fuel burner to be inserted into a burner throat bored in a wall portion of a furnace, comprising: a solid fuel nozzle for ejecting mixed fluid of solid fuel and primary air; a secondary air nozzle for ejecting secondary air; a tertiary air nozzle for ejecting tertiary air; a secondary air guide member for guiding a flow of the secondary air outwardly in a radial direction; and one or more tertiary air guide members for guiding a flow of the tertiary air outwardly in the radial direction at a first angle with respect to a central axis (C) of the solid fuel burner, wherein a distal end position (X2) of each of the tertiary air guide members in an axial direction of the solid fuel burner is at a closer side of the furnace than a distal end position (X1) of the secondary air guide member.

Abstract: This solid fuel burner is provided with: a venturi tube in which a channel for mixed fluid in a fuel nozzle narrows toward the center in the channel cross section; a fuel concentrator that imparts, to the mixed fluid, a velocity component away from the center of the fuel nozzle; and a channel separation member that separates the channel of the fuel nozzle into an internal side and an external side; wherein the channel separation member is shaped in such a way that the cross sectional area of an external channel is larger at the downstream end than at the upstream end, and the upstream end of the fuel concentrator is located between the upstream end and the downstream end of an expanded portion of the venturi tube. This solid fuel burner prevents solid fuel particles, which is ground biomass fuel, from adhering and depositing inside the nozzle.

Abstract: The present invention provides a solid fuel burner which ensures ignition performance and flame holding performance of a fuel nozzle. The present invention provides a solid fuel burner which achieves cost reduction by simplifying the structure of the fuel nozzle, for example, and which ensures the ignition performance and flame holding performance of the fuel nozzle. Further, the present invention provides a burner which enables stable combustion by both solid fuel and oil combustion with the suppression of soot and dust and mist generated during the oil start-up envisaged.

Abstract: In accordance with the flow distribution of combustion gas including an unburned portion, an after-air port (AAP) arranged downstream of the two-stage combustion burner can effectively reduce the unburned portion by dividing as appropriate so as to avoid interaction, and by mixing together, two types of after-air having functions of linearity and spreading. As the configuration of this AAP, a primary nozzle for supplying primary after-air and having a vertical height greater than the horizontal width is provided in the center in the opening of the AAP, a secondary nozzle for supplying secondary after-air is provided in the opening outside of the primary nozzle, and one or more secondary after-air guide vanes having a fixed or variable tilt angle relative to the after-air port center axis are provided at the outlet of the said secondary nozzle to deflect and supply the secondary after-air horizontally to the left or right.

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 boiler operating method operates a boiler by switching between air combustion mode and oxygen combustion mode when burning fossil fuel with first combustion gas and second combustion gas. The second combustion gas compensates for oxygen deficiency in the first combustion gas. The air combustion mode uses air as the first combustion gas and the second combustion gas while the oxygen combustion mode uses mixed gas of combustion flue gas and oxygen-rich gas as the first combustion gas and the second combustion gas, the combustion flue gas being produced when the fossil fuel is burned. By mixing the oxygen-rich gas in the air in the process of switching between air combustion mode and oxygen combustion mode, the air being the first combustion gas used in the air combustion mode, the boiler operating method can switch between the air combustion mode and oxygen combustion mode while maintaining stable combustion.

Abstract: In accordance with the flow distribution of combustion gas including an unburned portion, an after-air port (AAP) arranged downstream of the two-stage combustion burner can effectively reduce the unburned portion by dividing as appropriate so as to avoid interaction, and by mixing together, two types of after-air having functions of linearity and spreading. As the configuration of this AAP, a primary nozzle for supplying primary after-air and having a vertical height greater than the horizontal width is provided in the center in the opening of the AAP, a secondary nozzle for supplying secondary after-air is provided in the opening outside of the primary nozzle, and one or more secondary after-air guide vanes having a fixed or variable tilt angle relative to the after-air port center axis are provided at the outlet of the said secondary nozzle to deflect and supply the secondary after-air horizontally to the left or right.

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 spray nozzle is provided with upper and lower channels and from respective surfaces, the two channels form a cross shape, and become a fuel spray hole by communication of an intersecting part. A guide member is provided, in contact with the upstream-side channel, in a position overlapped with the intersecting part with respect to the spray direction of the spray nozzle. Spray fluid is branched with the guide member from the fuel fluid duct connected to the spray nozzle, passes through the upstream-side channel, to the intersecting part, and is sprayed. The spray fluid forms opposed flows toward the intersecting part in the upstream-side channel to collide with each other at an obtuse angle of 90° or greater, then is sprayed from the intersecting part, to form a thin fan-shaped liquid film. The liquid film is divided by a shearing force from the peripheral gas, atomized into spray particles.

Abstract: An oxygen combustion system includes a boiler to burn fuel using combustion gas composed of oxygen-rich gas and circulating flue gas, a dust remover disposed in a flue through which flue gas discharged from the boiler flows, a second flue leading the combustion gas to the boiler, the combustion gas being made by mixing the circulating flue gas extracted downstream of the dust remover with the oxygen-rich gas, a combustion gas heater exchanging heat between the flue gas flowing between the boiler and dust remover and the combustion gas flowing through the second flue, and a flue gas cooler disposed between the heater and the dust remover to cool the flue gas. A control unit controls at least one of a flow rate and cooling medium temperature of the flue gas cooler such that temperature of the flue gas introduced into the dust remover will be between 90° C. and 140° C.

Abstract: A boiler operating method operates a boiler by switching between air combustion mode and oxygen combustion mode when burning fossil fuel with first combustion gas and second combustion gas. The second combustion gas compensates for oxygen deficiency in the first combustion gas. The air combustion mode uses air as the first combustion gas and the second combustion gas while the oxygen combustion mode uses mixed gas of combustion flue gas and oxygen-rich gas as the first combustion gas and the second combustion gas, the combustion flue gas being produced when the fossil fuel is burned. By mixing the oxygen-rich gas in the air in the process of switching between air combustion mode and oxygen combustion mode, the air being the first combustion gas used in the air combustion mode, the boiler operating method can switch between the air combustion mode and oxygen combustion mode while maintaining stable combustion.

Abstract: The invention provides a combustion apparatus which can inhibit an NOx generation even in the case of promoting a mixing between a high-temperature combustion gas and an air so as to intend to reduce an unburned combustible. In a combustion apparatus provided with a burner burning a fuel within a furnace in a theoretical air ratio or less, and an air port supplying a combustion air for a shortfall in the burner, a supply apparatus for supplying a nitrogen oxide generation inhibiting gas is provided in a mixing region between the both or near the mixing region. Further, the invention provides a wind box which can inhibit an NOx generation even in the case of promoting a mixing between a high-temperature combustion gas and an air so as to intend to reduce an unburned combustible.

Abstract: A overfiring air port of the present invention is to supply an incomplete combustion region with air making up for combustion-shortage, in a furnace in which the incomplete combustion region less than stoichiometric ratio is formed by a burner. Furthermore, the airport is characterized by comprising: a nozzle mechanism for injecting air including an axial velocity component of an air flow and a radial velocity component directed to a center line of the airport; and a control mechanism for controlling a ratio of these velocity components.

Abstract: A overfiring air port of the present invention is to supply an incomplete combustion region with air making up for combustion-shortage, in a furnace in which the incomplete combustion region less than stoichiometric ratio is formed by a burner. Furthermore, the airport is characterized by comprising: a nozzle mechanism for injecting air including an axial velocity component of an air flow and a radial velocity component directed to a center line of the airport; and a control mechanism for controlling a ratio of these velocity components.