Abstract: A solid fuel burner and its combustion method suited for encouraging fuel ignition and avoiding slugging caused by combustion ash, wherein a gas of low oxygen concentration (exhaust combustion gas) is used as a carrier gas of such a low grade solid fuel as brown coal. An additional air nozzle for jetting additional air having a velocity component in the circumferential direction of a fuel nozzle is provided in the fuel nozzle, thereby encouraging mixing between the fuel and air in the fuel nozzle. Further, the amount of air supplied from the additional air nozzle is adjusted in response to the difference in combustion loads. Under light load, the amount of air supplied from the additional air nozzle is increased so as to increase the oxygen concentration of the circulating flow formed downstream of the outside of the outlet of the fuel nozzle, whereby stable combustion is ensured.

Abstract: An after-air nozzle capable of reducing NOx and CO and a boiler equipped with such a nozzle are provided The after-air nozzle has a vena contracta such that an outside diameter of a flow passage diminishes towards the air-jetting port which supplies air to a boiler, and a changing apparatus changes a flow passage cross-sectional area of the vena contracta. A method of use of such an after-air nozzle and a boiler so equipped is also provided.

Abstract: The present invention provides a solid fuel burner, which, while rendering the capacity larger than that in the conventional art, can suppress an increase in an unignited region and thus can realize the prevention of an increase in NOx concentration in a combustion gas and the prevention of a lowering in combustion efficiency, and a combustion equipment and boiler including the burner. The burner includes a fuel-containing fluid supply nozzle (12) which supplies a fuel-containing fluid, from a connecting part in a fluid transfer flow passage (10) for transferring a fuel-containing fluid including a fuel and a medium for transfer of the fuel, toward an outlet part provided on the wall of a furnace (4).

Abstract: A solid-fuel burner comprising a fuel nozzle for injecting a mixed fluid with a mixture of solid fuel and air as a carrier gas thereof, a plurality of air nozzles provided on the outside of the fuel nozzle for surrounding the fuel nozzle; an end portion of an inner circumferential wall of the air nozzle located at least at the outermost circumference is outwardly expanded, and an inductive member provided at outlet of the air nozzle located at least on the outermost circumference so as to direct flow of air in the direction of outer circumference.

Abstract: A pulverized coal combustion boiler 100 comprising: a furnace 50; a plurality of burners 6 for supplying and burning pulverized coal fuel in the furnace arranged at positions of a plurality of stages having different heights on a furnace front wall 51 and a furnace rear wall 52 of furnace wall surfaces forming the furnace 50, the furnace rear wall 52 arranged for facing the furnace front wall 51; a plurality of mills 2 arranged for supplying the pulverized coal fuel to the plurality of burners 6 arranged at each of the plurality of stages; and pulverized fuel pipes 5 arranged for distributing and supplying the pulverized coal to the plurality of burners 6 at each of the stages of the furnace front wall 51 and the furnace rear wall 52 from each of the plurality of mills 2.

Abstract: There is disclosed a solid fuel boiler including: a furnace including a plurality of solid fuel burners and a furnace wall to perform horizontal firing; a duct through which a part of combustion exhaust gas recirculates to a furnace from a downstream side of the furnace; heat exchanger tubes disposed on a furnace wall and in a heat recovery area of the furnace; and recirculation gas ports via which the recirculation gas is supplied to a reducing flame portion of the burners in the furnace without combining the gas with a flame in the vicinity of an outlet of the burner, so that molten ash is prevented from firmly sticking to the furnace wall and thermal NOx, fuel NOx, and unburned carbon.

Abstract: A solid fuel burner and its combustion method suited for encouraging fuel ignition and avoiding slugging caused by combustion ash, wherein a gas of low oxygen concentration (exhaust combustion gas) is used as a carrier gas of such a low grade solid fuel as brown coal. Means for Solving the Subject An additional air nozzle 12 for jetting additional air having a velocity component in the circumferential direction of a fuel nozzle 11 is provided in the fuel nozzle 11, thereby encouraging mixing between the fuel and air in the fuel nozzle 11. Further, the amount of air supplied from the additional air nozzle 12 is adjusted in response to the difference in combustion loads. Under light load, the amount of air supplied from the additional air nozzle 12 is increased so as to increase the oxygen concentration of the circulating flow 19 formed downstream of the outside of the outlet of the fuel nozzle 11, whereby stable combustion is ensured.

Abstract: A solid fuel burner and its combustion method suited for encouraging fuel ignition and avoiding slugging caused by combustion ash, wherein a gas of low oxygen concentration (exhaust combustion gas) is used as a carrier gas of such a low grade solid fuel as brown coal. An additional air nozzle for jetting additional air having a velocity component in the circumferential direction of a fuel nozzle is provided in the fuel nozzle, thereby encouraging mixing between the fuel and air in the fuel nozzle. Further, the amount of air supplied from the additional air nozzle is adjusted in response to the difference in combustion loads. Under light load, the amount of air supplied from the additional air nozzle is increased so as to increase the oxygen concentration of the circulating flow formed downstream of the outside of the outlet of the fuel nozzle, whereby stable combustion is ensured.

Abstract: A solid-fuel burner comprising a fuel nozzle for injecting a mixed fluid with a mixture of solid fuel and air as a carrier gas thereof, a plurality of air nozzles provided on the outside of the fuel nozzle for surrounding the fuel nozzle; an end portion of an inner circumferential wall of the air nozzle located at least at the outermost circumference is outwardly expanded, and an inductive member provided at outlet of the air nozzle located at least on the outermost circumference so as to direct flow of air in the direction of outer circumference.

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: 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: An after-air nozzle capable of reducing NOx and CO and a boiler equipped with such a nozzle are provided The after-air nozzle has a vena contracta such that an outside diameter of a flow passage diminishes towards the air-jetting port which supplies air to a boiler, and a changing apparatus changes a flow passage cross-sectional area the vena contracta. A method of use of such an after-air nozzle and a boiler so equipped is also provided.

Abstract: There is disclosed a solid fuel boiler including: a furnace including a plurality of solid fuel burners and a furnace wall to perform horizontal firing; a duct through which a part of combustion exhaust gas recirculates to a furnace from a downstream side of the furnace; heat exchanger tubes disposed on a furnace wall and in a heat recovery area of the furnace; and recirculation gas ports via which the recirculation gas is supplied to a reducing flame portion of the burners in the furnace without combining the gas with a flame in the vicinity of an outlet of the burner, so that molten ash is prevented from firmly sticking to the furnace wall and thermal NOx, fuel NOx, and unburned carbon.

Abstract: In a burner of construction having a primary nozzle, a secondary nozzle and a tertiary nozzle, a partition wall partitioning the secondary nozzle and the tertiary nozzle and having a flow path change member provided thereon, the partition wall is formed so as to be movable in parallel to the burner axis to control jetting speeds and flow rates of secondary air and tertiary air, whereby it is possible to cool the burner constituent members while reducing NOx. The partition wall is composed of a fixed wall and a movable wall. The burner comprises a bypass passage through which tertiary air in the tertiary nozzle bypasses the tertiary nozzle to flow into the secondary nozzle or the primary nozzle.

Abstract: There is disclosed a solid fuel boiler including: a furnace including a plurality of solid fuel burners and a furnace wall to perform horizontal firing; a duct through which a part of combustion exhaust gas recirculates to a furnace from a downstream side of the furnace; heat exchanger tubes disposed on a furnace wall and in a heat recovery area of the furnace; and recirculation gas ports via which the recirculation gas is supplied to a reducing flame portion of the burners in the furnace without combining the gas with a flame in the vicinity of an outlet of the burner, so that molten ash is prevented from firmly sticking to the furnace wall and thermal NOx, fuel NOx, and unburned carbon.

Abstract: Subject A solid fuel burner and its combustion method suited for encouraging fuel ignition and avoiding slugging caused by combustion ash, wherein a gas of low oxygen concentration (exhaust combustion gas) is used as a carrier gas of such a low grade solid fuel as brown coal. Means for Solving the Subject An additional air nozzle 12 for jetting additional air having a velocity component in the circumferential direction of a fuel nozzle 11 is provided in the fuel nozzle 11, thereby encouraging mixing between the fuel and air in the fuel nozzle 11. Further, the amount of air supplied from the additional air nozzle 12 is adjusted in response to the difference in combustion loads. Under light load, the amount of air supplied from the additional air nozzle 12 is increased so as to increase the oxygen concentration of the circulating flow 19 formed downstream of the outside of the outlet of the fuel nozzle 11, whereby stable combustion is ensured.

Abstract: There is disclosed a solid fuel boiler including: a furnace including a plurality of solid fuel burners and a furnace wall to perform horizontal firing; a duct through which a part of combustion exhaust gas recirculates to a furnace from a downstream side of the furnace; heat exchanger tubes disposed on a furnace wall and in a heat recovery area of the furnace; and recirculation gas ports via which the recirculation gas is supplied to a reducing flame portion of the burners in the furnace without combining the gas with a flame in the vicinity of an outlet of the burner, so that molten ash is prevented from firmly sticking to the furnace wall and thermal NOx, fuel NOx, and unburned carbon.

Abstract: According to a burner of the present invention, a stable combustion is obtained in a wide range from a high-load operation condition to a low-load operation condition even in the case of low quality solid fuel such as brown coal. The amount of air supplied from additional air holes or additional air nozzles 12 can be adjusted depending on the combustion load of furnace 41. At a low load, the amount of air supplied from additional air holes or additional air nozzles 12 is increased, whereby the oxygen concentration in a recirculation zones 19 formed downstream of the outside of a fuel nozzle 11 exit, permits a stable combustion. At a high load, the amount of air supplied from additional air holes or additional air nozzles 12 is reduced, whereby a flame is formed in a position far from the fuel nozzle 11. This suppresses thermal radiation onto a solid fuel burner 42 structure and a furnace 41 wall.

Abstract: The invention provides a boiler provided with low cost means which can reduce a concentration of CO, an unburned matter, an attached ash and the like near a side wall and maintain a combustion state well with a simple structure. In a boiler having a combustion chamber 13 formed by front and rear walls (burner walls) provided with a plural stages of burners 2, 3 and 4 on at least one of them and opposing to each other, and side walls 1a and 1b crossing to said burner walls 14a and 14b, a gas port 6 containing no fuel for making a pressure of a gas near said side walls 1a and 1b within said combustion chamber 13 higher than a pressure of a gas at a center portion of said combustion chamber 13 is provided between an outermost burner and the side walls 1a and 1b within a range of a height of said burner stages 2, 3 and 4. A combustion gas 16 can not come close to the side walls 1a and 1b due to the jet 18 of the gas.

Abstract: According to a burner of the present invention, a stable combustion is obtained in a wide range from a high-load operation condition to a low-load operation condition even in the case of low quality solid fuel such as brown coal.