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 solid fuel burner is provided with a guide member arranged on an outer circumferential section of a distal end of a first gas nozzle so as to guide a fluid flowing through a second flow passage outward in a radial direction; and a contraction forming member that is arranged on an upstream side of the guide member with respect to the flow direction of the second flow passage so as to reduce the cross sectional area of the second flow passage. An outer diameter of the guide member is formed to be smaller than an inner diameter of an outer peripheral wall of a second gas nozzle. The first gas nozzle, the guide member, and the contraction forming member are configured so as to be integrally attachable/detachable along an axial direction of the first gas nozzle toward the outside of a furnace.

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 solid fuel burner is provided with a guide member arranged on an outer circumferential section of a distal end of a first gas nozzle so as to guide a fluid flowing through a second flow passage outward in a radial direction; and a contraction forming member that is arranged on an upstream side of the guide member with respect to the flow direction of the second flow passage so as to reduce the cross sectional area of the second flow passage. An outer diameter of the guide member is formed to be smaller than an inner diameter of an outer peripheral wall of a second gas nozzle. The first gas nozzle, the guide member, and the contraction forming member are configured so as to be integrally attachable/detachable along an axial direction of the first gas nozzle toward the outside of a furnace.

Abstract: 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.

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 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.

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: To inhibit corrosion of water wall tubes of a boiler and stabilize combustion on a burner during oxygen combustion operation, a boiler combustion system includes a boiler equipped with a burner and a two-staged combustion gas input port; a flue gas supply fan extracting flue gas from a flue gas treatment system via a flue gas circulation line; a combustion gas supply line, fuel carrier gas supply line, and two-staged combustion gas supply line branched off from the flue gas circulation line downstream of the flue gas supply fan; an oxygen supply line supplying oxygen-rich gas to the combustion gas supply line and fuel carrier gas supply line; combustion air supply fans; a switching unit switching operation between the flue gas supply fan and the combustion air supply fans; and dampers regulating gas flow rates on the combustion gas supply line and the two-staged combustion gas supply line, respectively.

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: 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 pulverized coal-fired boiler efficiently supplies air to a central part of a furnace and the neighborhood of a furnace wall, thereby promoting mixture with combustion gas, and reducing both NOx and CO. The main after air ports are structured so as to jet air having a large momentum for enabling arrival at the central part of the furnace, and the sub-after air ports are structured so as to jet air having a small momentum to the neighborhood of the wall face of the furnace, and a sectional center of each of the sub-after air ports is within a range from 1 to 5 times of a caliber of the main after air ports from a sectional center of each of the main after air ports.

Abstract: To inhibit corrosion of water wall tubes of a boiler and stabilize combustion on a burner during oxygen combustion operation, a boiler combustion system includes a boiler equipped with a burner and a two-staged combustion gas input port; a flue gas supply fan extracting flue gas from a flue gas treatment system via a flue gas circulation line; a combustion gas supply line, fuel carrier gas supply line, and two-staged combustion gas supply line branched off from the flue gas circulation line downstream of the flue gas supply fan; an oxygen supply line supplying oxygen-rich gas to the combustion gas supply line and fuel carrier gas supply line; combustion air supply fans; a switching unit switching operation between the flue gas supply fan and the combustion air supply fans; and dampers regulating gas flow rates on the combustion gas supply line and the two-staged combustion gas supply line, respectively.

Abstract: A pulverized coal-fired boiler efficiently supplies air to a central part of a furnace and the neighborhood of a furnace wall, thereby promoting mixture with combustion gas, and reducing both NOx and CO. The main after air ports are structured so as to jet air having a large momentum for enabling arrival at the central part of the furnace, and the sub-after air ports are structured so as to jet air having a small momentum to the neighborhood of the wall face of the furnace, and a sectional center of each of the sub-after air ports is within a range from 1 to 5 times of a caliber of the main after air ports from a sectional center of each of the main after air ports.

Abstract: A pulverized coal-fired boiler efficiently supplies air to a central part of a furnace and the neighborhood of a furnace wall, thereby promoting mixture with combustion gas, and reducing both NOx and CO. The main after air ports are structured so as to jet air having a large momentum for enabling arrival at the central part of the furnace, and the sub-after air ports are structured so as to jet air having a small momentum to the neighborhood of the wall face of the furnace, and a sectional center of each of the sub-after air ports is within a range from 1 to 5 times of a caliber of the main after air ports from a sectional center of each of the main after air ports.

Abstract: The present invention provides a highly reliable pulverized coal boiler that ensures suppression of a rise in flame temperature caused during the combustion of an unburnt gas in a furnace when combustion air is supplied from after-air ports so as to reduce the concentration of thermal NOx generated during the combustion.

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.