Abstract: Provided are a pulverized coal boiler with a bottom combustor, and a control method for the pulverized coal boiler, wherein the pulverized coal boiler includes a furnace, at least one bottom combustor and a secondary air distributing device. Each combustor is provided with a combustor spout, and the secondary air distributing device surrounds the combustor and is arranged at the bottom of the furnace. The secondary air distributing device includes an internal secondary air distributing device and an external secondary air distributing device, wherein the internal secondary air distributing device includes an internal secondary air gathering box and an internal secondary air pipe, and the external secondary air distributing device includes an external secondary air gathering box and an external secondary air pipe.

Abstract: A water-cooled column (4) used in a circulating fluidized bed boiler furnace is disclosed, wherein the water-cooled column is formed by connecting membrane water-cooled walls (41). The water-cooled column (4) includes a lower section (A), an upper section and a transition section. The lower section (A) is a single column and is provided with inner secondary air ports (400) on a side wall thereof. The upper section includes a plurality of sub-columns (B, C). The membrane water-cooled walls at the lower section (A) extend to the upper section through the transition section. Each of the sub-columns (B, C) is formed by connecting extension portions extending upward from respective membrane water-cooled walls (41) in the membrane water-cooled walls (41), which are connected to form the lower section (A), and the plurality of sub-columns (B, C) are separated from each other.

Abstract: The present disclosure provides a method for distributing gas for oxy-fuel combustion on a circulating fluidized bed. In the method, the gas is provided by three stages into a furnace of the circulating fluidized bed. The method includes: blowing in a first-stage gas containing oxygen and recycled flue gas from the bottom of the furnace; blowing in a second-stage gas containing recycled flue gas from a transition zone between a dense-phase zone and a dilute-phase zone of the furnace; and blowing in a third-stage gas containing oxygen from a side wall of the furnace.

Abstract: A circulating fluidized bed boiler is disclosed.

Abstract: The present invention provides a circulating fluidized bed boiler, comprising: furnace side walls; a ceiling; an air distribution plate provided at a bottom of a furnace; and at least one air distribution cone provided on the air distribution plate, wherein each air distribution cone extends upwards from the air distribution plate into an interior of the furnace and has a shape gradually tapered in an extending direction, cone side walls which form the air distribution cone are provided with secondary air ports, the cone side walls are separated from the furnace side walls, and a furnace combustion space is formed and surrounded by the ceiling, the furnace side walls, the air distribution plate, and the cone side walls.

Abstract: Embodiments of the invention provide a water-cooled column formed by side walls connected together to define an enclosed space, each side wall is formed of a water-cooled membrane wall, a working medium is passed through a tube of the water-cooled membrane wall from bottom to top, the water-cooled column comprising: a lower part having a cross section reduced segment, which has a cross section gradually reduced in a direction from bottom to top; and an upper part, wherein the upper part connects with the cross section reduced segment at a connection position, and a cross sectional area of the cross section reduced segment at the connection position is identical to a cross sectional area of the upper part at the connection position. Embodiments of the invention also provide a furnace for defining a reaction space, which comprises a water-cooled column defined as above disposed along a vertical direction therein.

Abstract: A water-cooled column (4) used in a circulating fluidized bed boiler furnace is disclosed, wherein the water-cooled column is formed by connecting membrane water-cooled walls (41). The water-cooled column (4) includes a lower section (A), an upper section and a transition section. The lower section (A) is a single column and is provided with inner secondary air ports (400) on a side wall thereof. The upper section includes a plurality of sub-columns (B, C). The membrane water-cooled walls at the lower section (A) extend to the upper section through the transition section. Each of the sub-columns (B, C) is formed by connecting extension portions extending upward from respective membrane water-cooled walls (41) in the membrane water-cooled walls (41), which are connected to form the lower section (A), and the plurality of sub-columns (B, C) are separated from each other.

Abstract: The present disclosure provides a method for distributing gas for oxy-fuel combustion on a circulating fluidized bed. In the method, the gas is provided by three stages into a furnace of the circulating fluidized bed. The method includes: blowing in a first-stage gas containing oxygen and recycled flue gas from the bottom of the furnace; blowing in a second-stage gas containing recycled flue gas from a transition zone between a dense-phase zone and a dilute-phase zone of the furnace; and blowing in a third-stage gas containing oxygen from a side wall of the furnace.

Abstract: Embodiments of the invention provide a water-cooled column formed by side walls connected together to define an enclosed space, each side wall is formed of a water-cooled membrane wall, a working medium is passed through a tube of the water-cooled membrane wall from bottom to top, the water-cooled column comprising: a lower part having a cross section reduced segment, which has a cross section gradually reduced in a direction from bottom to top; and an upper part, wherein the upper part connects with the cross section reduced segment at a connection position, and a cross sectional area of the cross section reduced segment at the connection position is identical to a cross sectional area of the upper part at the connection position. Embodiments of the invention also provide a furnace for defining a reaction space, which comprises a water-cooled column defined as above disposed along a vertical direction therein.

Abstract: The present invention provides a circulating fluidized bed boiler, comprising: furnace side walls; a ceiling; an air distribution plate provided at a bottom of a furnace; and at least one air distribution cone provided on the air distribution plate, wherein each air distribution cone extends upwards from the air distribution plate into an interior of the furnace and has a shape gradually tapered in an extending direction, cone side walls which form the air distribution cone are provided with secondary air ports, the cone side walls are separated from the furnace side walls, and a furnace combustion space is formed and surrounded by the ceiling, the furnace side walls, the air distribution plate, and the cone side walls.

Abstract: A circulating fluidized bed boiler is disclosed.