A combustion burner including: a fuel nozzle (61) which ejects a fuel gas that is a mixture of fuel and air; a combustion air nozzle (62) which ejects air from an outer side of the fuel nozzle (61); first members (71) which are arranged inside the fuel nozzle (61) and which each comprise a first inclined surface (82a) inclined with respect to the flow of the fuel gas, and a first inclination end edge where the inclination of the first inclined surface (82a) ends; and second members (72) which are arranged downstream of the first inclination end edges in the direction of fuel gas flow, and which each comprise a second inclined surface (84a) inclined towards the first members (71) with respect to the fuel gas flow and a second inclination end edge where the inclination of the second inclined surface (84a) ends.

A combustion burner including: a fuel nozzle (61) which ejects a fuel gas that is a mixture of fuel and air; a combustion air nozzle (62) which ejects air from an outer side of the fuel nozzle (61); first members (71) which are arranged inside the fuel nozzle (61) and which each comprise a first inclined surface (82a) inclined with respect to the flow of the fuel gas, and a first inclination end edge where the inclination of the first inclined surface (82a) ends; and second members (72) which are arranged downstream of the first inclination end edges in the direction of fuel gas flow, and which each comprise a second inclined surface (84a) inclined towards the first members (71) with respect to the fuel gas flow and a second inclination end edge where the inclination of the second inclined surface (84a) ends.

A burner includes: an inner gas nozzle which extends along an axis while surrounding the axis, and which is capable of supplying a furnace with an inner combustion oxygen containing gas; a fuel supply nozzle surrounding the inner gas nozzle as seen in a direction along the axis, the fuel supply nozzle being capable of supplying the furnace with a fluid mixture of a solid powder fuel and a carrier gas; an outer gas nozzle surrounding the fuel supply nozzle as seen in the direction along the axis, the outer gas nozzle being capable of supplying the furnace with an outer combustion oxygen containing gas; and a flow-velocity-ratio adjustment apparatus capable of adjusting a relative flow velocity ratio of a discharge flow velocity of the inner combustion oxygen containing gas to a discharge flow velocity of the outer combustion oxygen containing gas.

A burner includes: an inner gas nozzle which extends along an axis while surrounding the axis, and which is capable of supplying a furnace with an inner combustion oxygen containing gas; a fuel supply nozzle surrounding the inner gas nozzle as seen in a direction along the axis, the fuel supply nozzle being capable of supplying the furnace with a fluid mixture of a solid powder fuel and a carrier gas; an outer gas nozzle surrounding the fuel supply nozzle as seen in the direction along the axis, the outer gas nozzle being capable of supplying the furnace with an outer combustion oxygen containing gas; and a flow-velocity-ratio adjustment apparatus capable of adjusting a relative flow velocity ratio of a discharge flow velocity of the inner combustion oxygen containing gas to a discharge flow velocity of the outer combustion oxygen containing gas.

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.

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.

An oxy-gaseous fuel burner (400, 500) or a solid fuel burner (700) having an annular cavity (404, 504, 704) upstream from and proximate to an outlet plane (416, 516, 716) and a converging (434, 734) or converging-diverging nozzle (537) located upstream from and proximal to the cavity (404, 504, 704). The solid fuel burner (700) also is preferably operated so that the velocity of gas exiting a second annulus (730) is less than the velocity of gas exiting a central conduit (710).

An oxy-gaseous fuel burner (400, 500) or a solid fuel burner (700) having an annular cavity (404, 504, 704) upstream from and proximate to an outlet plane (416, 516, 716) and a converging (434, 734) or converging-diverging nozzle (537) located upstream from and proximal to the cavity (404, 504, 704). The solid fuel burner (700) also is preferably operated so that the velocity of gas exiting a second annulus (730) is less than the velocity of gas exiting a central conduit (710).

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. The solid fuel burner of the present invention includes: a fuel nozzle straight tube portion allowing a mixing gas of a solid fuel and its carrier gas to flow therethrough; a fuel nozzle throttling portion narrowing a flow passage of the mixing gas passed through the fuel nozzle straight tube portion; a fuel nozzle diffusion portion horizontally expanding the flow passage of the mixing gas passed through the fuel nozzle throttling portion; a fuel nozzle outlet portion connected to the fuel nozzle diffusion portion and having an outlet flattened in shape; a ring-shaped outer peripheral flame stabilizer disposed on an outer periphery of the fuel nozzle outlet portion; and an inner flame stabilizer disposed in the fuel nozzle outlet portion and horizontally dividing the mixing gas passed through the fuel nozzle diffusion portion.

A combustion system is capable of using a petroleum pitch fuel, and is provided with a burner having a fuel supply pipe where a flame stabilizing plate is formed in a tip end of the same, and a high temperature maintaining unit for maintaining an atmosphere temperature at a vicinity of the flame stabilizing plate during operation higher than a softening point of the petroleum pitch fuel. Thus, even when the petroleum pitch is used as fuel, the burner does not become unusable due to adhesion/solidification of the petroleum pitch inside the burner and combustion operation can be continued for a long time.