Air distribution device of fluidized bed and boiler or gasification furnace with air distribution device

Abstract

The invention relates to an air distribution device of a fluidized bed used for a boiler or a gasification furnace. The air distribution device comprises an air inlet header pipe, a plurality of air distribution pipes and a plurality of blast caps, wherein one end of each air distribution pipe is communicated with the air inlet header pipe; the plurality of blast caps are respectively arranged on outlets formed by the other ends of the corresponding air distribution pipes; and at least two air distribution pipes are arranged in a nonparallel manner, and a hearth bottom slag passage is formed by gaps between the air distribution pipes. The invention also relates to a fluidized-bed boiler or the gasification furnace. The fluidized-bed boiler or the gasification furnace comprises a hearth and the air distribution device, wherein hearth bottom slag is discharged from a hearth bottom slag outlet of the hearth through the hearth bottom slag passage.

Description

technical field [0001] The invention relates to an air distribution device for a fluidized bed of a boiler or a gasification furnace and a boiler or a gasification furnace with the same. Background technique [0002] The air distribution device of the fluidized bed is an important part of the fluidized bed. The existing fluidized bed air distribution device mainly has two forms, one is the air distribution plate, and the other is the air distribution pipe. [0003] The air distribution plate type air distribution device usually consists of an air distribution plate with a hood, an air chamber under the air distribution plate, and a slag discharge pipe connected to the slag discharge port on the air distribution plate and passing through the air chamber. Its main functions include: (1) Support the bed material; (2) Evenly distribute the air to avoid fluidization dead zone in the furnace; (3) Prevent the bed material from leaking into the air chamber; (4) Discharge the bottom ...

AI Technical Summary

Problems solved by technology

[0005] Existing fluidized bed air distribution devices for boilers or gasifiers have two defects. One is that the bottom slag is discharged from the furnace through the gap between the slag discharge pipe or the air distribution pipe, resulting in high temperature bottom slag being discharged without being cooled. The furnace fails to make full use of its sensible heat; another defect is that due to the needs of supporting the bed material, water cooling and uniform air distribution, it is difficult to let the large-sized bottom The slag passes through smoothly. For example, if the diameter of the slag outlet is too large, it will directly make it difficult to arrange the water-cooled pipes of the air distribution plate. If the distance between the air distribution pipes is too large, the number of air caps that can be arranged at the bottom of the furnace will be reduced, which is not good for uniform air distribution; especially in In the fluidized bed gasifier, in order to pursue a higher carbon conversion rate, a higher reaction temperature is required, and local coking is prone to occur at high temperatures, resulting in larger coke blocks. In the biomass direct combustion circulating fluidized bed In the boiler, biomass ash is prone to cohesion and large agglomerates. If these coke or agglomerates cannot be discharged in time, they will accumulate at the bottom of the furnace, affecting the normal fluidization in the furnace and eventually causing gas Furnace or boiler not functioning properly

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